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63 evidence-tiered profiles. Every claim is graded and traced to the research it came from.
Afamelanotide is a lab-made, longer-lasting version of a natural hormone (α-MSH) that tells pigment cells in the skin to make more of the dark protective pigment eumelanin. It does this by switching on the melanocortin-1 receptor (MC1R). The extra pigment builds up in the skin even without sun exposure, acting like a built-in sunscreen that reduces how much light penetrates. It also appears to boost the skin's antioxidant and DNA-repair defenses and to calm inflammation. In people with erythropoietic protoporphyria (EPP), this lets them tolerate more light and spend more pain-free time in sunlight.
Bremelanotide is a lab-made version of a natural hormone (alpha-MSH) that acts in the brain rather than on blood vessels. It switches on melanocortin receptors (mainly MC4R, and also MC3R) in the hypothalamus, tuning brain circuits involved in sexual desire and arousal. By influencing dopamine-related pathways, it is thought to increase sexual motivation. This is different from erectile-dysfunction pills like sildenafil, which work on blood flow and nitric oxide in the penis.
According to Novo Nordisk development papers and reviews, cagrilintide is a long-acting synthetic version of amylin, a hormone the pancreas releases alongside insulin after meals to signal fullness. Consumer and pharmacy web material describe it as designed to activate amylin receptors in the brainstem, aiming to reduce appetite, boost fullness, slow the stomach's emptying, suppress the post-meal release of glucagon and help regulate blood sugar. It is engineered for once-weekly injection. Reviews note it is frequently combined with the GLP-1 drug semaglutide (as CagriSema) because the two work through separate routes, which sources describe as complementary and potentially additive for appetite reduction and glucose control.
Cerebrolysin is not a single molecule but a liquid preparation made from pig brain tissue, broken down by enzymes into a mix of free amino acids (roughly 75%) and small peptides under about 10,000 daltons (roughly 25%). These small components are thought to be able to cross into the brain and behave like the body's own natural nerve-growth signals (such as BDNF, NGF, GDNF and CNTF), helping nerve cells survive, form new connections, and grow. Researchers propose it protects neurons by reducing cell death, calming inflammation, lowering oxidative stress (free radicals), and supporting blood vessels in the brain. Because peptides are destroyed in the gut, it is given by injection or infusion rather than by mouth. It is approved in many countries for stroke, traumatic brain injury and dementia, but has never been approved by the U.S. FDA, and rigorous reviews disagree on how much real benefit it provides.
According to Phase 1 trial reports and multiple reviews, CJC-1295 is a long-acting synthetic version of growth-hormone-releasing hormone (GHRH). Sources describe it as being built from the first 29 amino acids of natural GHRH with four amino-acid substitutions that make it resist breakdown by enzymes. The DAC (Drug Affinity Complex) version carries a chemical group that latches onto albumin, a blood protein, which sources say extends its active life from minutes to roughly a week. Reviews describe it binding the GHRH receptor on pituitary somatotroph cells to prompt the body's own growth hormone (GH) release, which in turn raises IGF-1. Sources emphasize that, unlike injecting GH directly, it amplifies the body's existing pulsatile GH pattern rather than replacing it.
Cortexin is not a single molecule but a mixture of small water-soluble polypeptides (roughly 1,000–10,000 Da) extracted from the cerebral cortex of young cattle and pigs, along with amino acids and trace elements. It is proposed to act as a broad, multi-target neuroprotectant. Laboratory studies suggest its peptides bind to receptors that handle the brain's main excitatory (glutamate) and inhibitory (GABA) signaling, which could dampen overexcitation (excitotoxicity). It is also reported to protect neurons from damaging factors like glutamate excess, calcium overload, and free radicals, to reduce a step in the cell-death (apoptosis) cascade, to support the brain's antioxidant and anti-inflammatory balance, and to encourage nerve-cell survival, growth, and connections in ways compared to natural growth factors. It is claimed to help balance neurotransmitters (including dopamine and serotonin). It is used clinically in Russia and CIS countries as an injectable for stroke, brain injury, cognitive problems, and pediatric developmental issues, though independent reviewers judge the human evidence weak.
Davunetide (NAP) is a short 8-amino-acid piece of a natural brain protein called ADNP (activity-dependent neuroprotective protein). Its main proposed action is to help stabilize microtubules — the internal scaffolding of nerve cells — and to reduce abnormal phosphorylation of the tau protein that, when overloaded, forms toxic tangles seen in diseases like Alzheimer's. By binding to microtubule end-binding proteins and helping tau attach to microtubules, it is proposed to protect neurons from damage, prevent cell death, and support the growth of nerve fibers and synapses. Additional proposed effects include anti-inflammatory activity, antioxidant activity, and reducing protein aggregation.
Elafin (also called Trappin-2 or SKALP) is described by DrugBank as a human protein made naturally in the skin, lung and breast that protects tissue from destruction by the immune system and blocks destructive enzymes involved in inflammation. A vendor profile and reviews describe it as an endogenous serine protease inhibitor produced by epithelial cells at mucosal surfaces that blocks neutrophil enzymes (elastase and proteinase 3) and also has direct antimicrobial activity against bacteria and fungi (vendor claim). Because the enzyme elastase is increased in pulmonary hypertension and inflammatory tissue damage, researchers have investigated giving extra elafin to dampen this damage. In its most rigorous human test — a randomised trial in heart-bypass surgery patients — elafin dramatically raised blood elafin levels and inhibited elastase but did not reduce heart-muscle injury over 48 hours.
Hexarelin is a synthetic six-amino-acid peptide that acts as a growth hormone secretagogue. It mimics the natural hormone ghrelin by binding to the growth hormone secretagogue receptor (GHS-R1a) on the pituitary gland, prompting a strong, pulsatile release of growth hormone. It also acts at the hypothalamus to boost GHRH activity and reduce somatostatin's braking effect. Because release stays pulsatile and subject to normal feedback, it tends to avoid continuously supra-physiologic GH levels. Beyond growth hormone, hexarelin engages a separate cardiac receptor (CD36) that produces heart-related effects independent of growth hormone, and it mildly stimulates cortisol, ACTH, and prolactin.
Vendor and educational profiles describe ipamorelin (NNC 26-0161) as a synthetic five-amino-acid peptide that mimics the natural hunger hormone ghrelin by switching on the ghrelin receptor (GHSR-1a) in the pituitary gland and hypothalamus (vendor claim). According to these sources, this prompts the pituitary to release a pulse of growth hormone (GH), which in turn raises IGF-1 and is said to drive protein synthesis, fat breakdown and tissue repair. What multiple profiles emphasize is its selectivity: animal studies reported that ipamorelin releases GH without raising cortisol, prolactin, ACTH or other pituitary hormones, and expert commentary notes it does so while preserving the body's natural pulsatile GH rhythm rather than flooding the system with a constant elevation.
Investigators describe lactoferrin as a natural iron-binding defence protein found in milk, tears, saliva, other body fluids and neutrophils, with a broad range of reported functions: killing microbes, calming inflammation, acting as an antioxidant and helping regulate cell growth and the immune system. Researchers report it works partly by sequestering the iron that many pathogens need to grow while sparing beneficial commensals such as lactobacilli and bifidobacteria, and partly through short positively charged sequences at its N-terminus that bind and disrupt microbial cell surfaces. Reviewers note that ingested lactoferrin is also taken up by cells through a receptor-mediated pathway that can influence gene transcription and immune function. The peptide fragment hLF1-11 represents the first 11 amino acids of human lactoferrin, which investigators say carry much of its antimicrobial and anti-inflammatory activity.
Multiple sources describe larazotide acetate (also called AT-1001 and INN-202) as a small, 8-amino-acid oral peptide that acts locally in the gut without being absorbed into the bloodstream. Reviews explain that in celiac disease, gluten triggers the release of a protein called zonulin, which loosens the 'tight junctions' between the cells lining the intestine, letting gluten fragments slip through and provoke an immune reaction. Reviews report that larazotide is thought to work as a zonulin antagonist — helping the tight junctions close and reassemble, so the gut barrier stays intact and gluten is kept from reaching the tissue underneath where it would spark inflammation.
Linaclotide is a small 14-amino-acid peptide that mimics the body's natural guanylin hormones. Taken by mouth, it stays inside the gut and switches on a receptor called guanylate cyclase-C (GC-C) on the lining of the intestine. This raises a signaling molecule called cGMP, which prompts the gut to secrete chloride, bicarbonate, and fluid into the intestine. The extra fluid softens stool and speeds up movement through the bowel, relieving constipation. The rise in cGMP also appears to reduce gut pain signaling, which helps with the abdominal pain and bloating of IBS-C. Because it is barely absorbed into the bloodstream, its effects are almost entirely local to the intestine.
Melanotan II is a lab-made, ring-shaped copy of the natural hormone alpha-MSH that our bodies use to signal skin pigment cells. It switches on melanocortin receptors (MC1R, MC3R, MC4R and MC5R), which raises a cell-signaling molecule called cyclic AMP. In the skin this ramps up production of the dark pigment eumelanin, tanning the skin even without sunlight and offering some UV protection. Because it also hits receptors in the brain, it can trigger erections and sexual desire, suppress appetite, and affect glands — effects that cannot be separated from the tanning effect because the peptide is non-selective. It is far more potent than the natural hormone and its ring structure makes it last longer than natural alpha-MSH before being broken down.
MK-677 (ibutamoren) is an orally active, non-peptide molecule that mimics the hunger hormone ghrelin. It switches on the ghrelin receptor (GHS-R1a) in the pituitary gland and hypothalamus, prompting the body to release more of its own growth hormone (GH), which in turn raises IGF-1. Unlike injected GH, it amplifies the body's natural pulsing pattern of GH release without shutting down the normal feedback system. Because it survives stomach digestion, it can be taken by mouth once daily and keeps GH and IGF-1 elevated for up to about 24 hours. Through the same ghrelin pathway it also increases appetite and can affect sleep, insulin sensitivity, and repair processes.
Oxytocin is a small nine-amino-acid hormone made in the hypothalamus and released from the posterior pituitary gland, as described across multiple reviews and the FDA prescribing information. Its best-established action, per the Pitocin label, is stimulating rhythmic contractions of the uterine smooth muscle by raising intracellular calcium, an effect that becomes strong toward the end of pregnancy when uterine receptors are most abundant. Beyond the uterus, reviews describe oxytocin acting in the brain as a 'prosocial' signaling molecule linked to social recognition, bonding, trust, empathy, stress responses and anxiety, though human behavioral findings are mixed and often fail to confirm effects seen in animals.
Plecanatide is a synthetic 16-amino-acid peptide that mimics a natural human hormone called uroguanylin. It works locally inside the gut by switching on a receptor (guanylate cyclase-C, or GC-C) on the surface of intestinal lining cells. This triggers the cells to pump chloride and bicarbonate into the intestine, which draws in more fluid, softens stool, and speeds up movement through the bowel. It is designed to stay in the gut and is barely absorbed into the bloodstream. Animal studies also suggest it can quiet pain-sensing nerves in the intestine.
Multiple clinical trial reports describe retatrutide (LY3437943) as a single peptide that switches on three gut and metabolic hormone receptors at once: the GIP receptor, the GLP-1 receptor, and the glucagon receptor. According to Eli Lilly and mechanistic reviews, activating GLP-1 boosts glucose-dependent insulin release, slows stomach emptying and increases feelings of fullness; activating GIP also aids insulin release and lipid handling; and activating the glucagon receptor raises energy expenditure, thermogenesis and fat mobilization while reducing food intake. The combined result reported across trials is dose-dependent weight loss and improved blood-sugar control. A fatty diacid attached to the peptide extends its half-life to roughly 6 days, allowing once-weekly injection.
Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist that mimics the natural gut hormone GLP-1. It tells the pancreas to release more insulin and less glucagon, but only when blood sugar is elevated, which lowers blood glucose with a low risk of hypoglycemia. It also acts on appetite regulation and slows the rate at which the stomach empties, leading to reduced food intake and weight loss.
Sermorelin is a lab-made copy of the active part of the body's own growth hormone-releasing hormone (GHRH). Rather than supplying growth hormone directly, it signals the pituitary gland to make and release its own growth hormone in natural bursts. That released growth hormone then prompts the liver to produce IGF-1. Because it works within the body's normal feedback loops, growth hormone release stays pulsatile and is still held in check by the body's natural braking hormone, somatostatin.
SS-31 (elamipretide) is a small synthetic peptide that homes in on the powerhouses of the cell — the mitochondria. It carries a positive charge and rapidly penetrates cells, accumulating hundreds to thousands of times over inside the inner mitochondrial membrane. There it binds tightly to cardiolipin, a special fat found only in mitochondria that is essential for keeping the energy-producing machinery organized and working. By protecting cardiolipin, SS-31 helps preserve mitochondrial structure, keeps the electron transport chain assembled, boosts ATP (energy) production, and reduces harmful reactive oxygen species at their source rather than mopping them up after the fact. It has been studied in Barth syndrome, mitochondrial myopathy, heart failure, kidney injury, and age-related macular degeneration, and in September 2025 received FDA accelerated approval (as Forzinity) to improve muscle strength in Barth syndrome patients weighing at least 30 kg.
Teduglutide is a lab-made, longer-lasting copy of a natural gut hormone called GLP-2. Like the natural hormone, it tells the cells lining the intestine to grow, repair themselves and resist dying off. This makes the intestinal surface healthier and better able to absorb fluids and nutrients. It also slows how fast the stomach empties, reduces excess stomach acid, and boosts blood flow to the gut. In people with short bowel syndrome — who have lost a lot of functional intestine — these effects help the remaining bowel absorb more, so they need less nutrition delivered through an IV (parenteral support).
Tesamorelin is a synthetic, stabilized version of growth hormone-releasing hormone (GHRH), the natural brain signal that tells the pituitary gland to release growth hormone. Rather than injecting growth hormone directly, tesamorelin prompts the body to release its own growth hormone in a natural, pulsing pattern. The extra growth hormone then drives the liver to make IGF-1 and promotes the breakdown of fat (lipolysis), which is why it reduces excess visceral (deep abdominal) fat in HIV-infected patients with lipodystrophy.
Thymosin alpha-1 is a 28-amino-acid peptide the thymus gland naturally makes; reviews describe it as long recognized for modifying, enhancing and restoring immune function. Sources report it helps train and coordinate immune cells — encouraging T cells to mature and specialize, activating natural killer cells and dendritic cells, and tuning the mix of signaling molecules (cytokines) the immune system releases. One web source attributes to it a dual capacity to both boost an underactive immune response and calm an overactive, inflammatory one. Much of this mechanistic picture comes from expert opinion, in vitro work and animal studies rather than human trials.
According to a Tier 1 review, tirzepatide is a once-weekly injectable that activates two gut-hormone receptors at once — the GIP receptor and the GLP-1 receptor (a 'dual incretin' agonist). A review explains that GIP and GLP-1 are incretin hormones the intestine releases after eating; they prompt the pancreas to release insulin when blood glucose is high, and GLP-1 also reduces food intake and slows stomach emptying. A peptide protocol wiki describes how GLP-1 receptor activation by tirzepatide boosts glucose-dependent insulin secretion, lowers glucagon, slows gastric emptying and reduces appetite through the hypothalamus, while GIP receptor activation adds to insulin secretion, may improve lipid metabolism and fat distribution, and enhances central appetite control (vendor claim). A pharmacokinetic study reports the glucose-lowering effect may reflect GIP-receptor-mediated insulin action plus improved insulin sensitivity independent of weight change, while weight loss reflects combined GIP- and GLP-1-mediated effects on satiety and food intake.
Triptorelin is a lab-made, more potent copy of the natural hormone (GnRH/LHRH) that tells the pituitary gland to release the reproductive hormones LH and FSH. When given continuously as a long-acting depot, it first causes a brief surge in these hormones (and in testosterone or estrogen) for a few weeks, then shuts the system down. This sustained shutdown drops testosterone in men to levels seen after surgical castration, and lowers estrogen in women, which is useful when a cancer or condition is fueled by sex hormones or when puberty needs to be paused. The effect wears off after the drug is stopped.
Alpha-MSH is a small, naturally occurring hormone (a 13-amino-acid peptide) that the body makes from a larger precursor protein called POMC. It is produced by skin cells after sun exposure and by the brain/pituitary. It works by switching on melanocortin receptors (MC1R, MC3R, MC4R, MC5R), which are found on many cell types. Through these receptors it drives skin tanning (melanin production), calms inflammation, dampens appetite (promotes feeling full), and influences glucose handling in muscle, immune activity, and sexual behavior. It binds MC1R most strongly, which is why pigment and anti-inflammatory effects are prominent.
Argireline is a small synthetic peptide designed to mimic part of a natural muscle-signaling protein (SNAP-25). By imitating this fragment, it is proposed to interfere with the machinery nerves use to release the chemical messenger (acetylcholine) that tells facial muscles to contract. The idea is that reducing these contractions softens the repeated creasing that forms expression lines, giving it a marketing reputation as a topical, needle-free alternative to Botox. Importantly, this mechanism is well supported in lab dishes but its relevance to topical cosmetic use is uncertain, because very little of the peptide actually penetrates the skin to reach facial muscles.
Several reviews describe BPC-157 as a synthetic 15-amino-acid peptide originally isolated from human gastric juice. Animal and in vitro studies report it promotes the growth of new blood vessels, helps cells migrate to repair tissue, and protects tissues from damage. Studies attribute these effects to its interaction with nitric oxide production and growth-factor signaling, and reviews report it appears especially effective in poorly-vascularized tissues such as tendons and ligaments. Almost all of this evidence is preclinical; human data are minimal.
DSIP (delta sleep-inducing peptide) is a small 9-amino-acid peptide first isolated from the blood of sleeping rabbits in the 1970s. It was named for its ability to increase deep, slow-wave (delta) sleep in animals. Despite decades of study, no specific DSIP receptor, gene, or precursor protein has ever been identified, so how it works remains unresolved. Rather than sedating like a sleeping pill, it appears to support natural sleep — increasing sleep depth and efficiency and creating a subjective feeling of sleep pressure without suppressing REM sleep or causing next-day grogginess. It seems to influence sleep indirectly through several brain systems (GABA, glutamate/NMDA, and opioid/enkephalin pathways), circadian rhythms, melatonin, and stress hormones, and it turns up in many tissues and body fluids. Its human sleep effects are strongest in people with disrupted sleep and modest in healthy sleepers.
Gonadorelin is a lab-made copy of the body's own gonadotropin-releasing hormone (GnRH), the master hormone from the hypothalamus that tells the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These in turn drive the testes and ovaries to make sex hormones and support sperm and egg development. A crucial feature is timing: the natural hormone is released in pulses every 90-120 minutes, and delivering gonadorelin in matching pulses keeps the pituitary responsive. If instead it is given continuously, the pituitary receptors shut down and hormone output paradoxically falls. Because of this, it is used both as a single-dose diagnostic test of pituitary function and, via a programmable pump giving pulses, to induce ovulation or restore fertility in people whose own hypothalamus is not producing GnRH.
HCG is a hormone normally made by the placenta during pregnancy. It is built from two pieces (an alpha subunit shared with the pituitary hormones LH, FSH and TSH, and a unique beta subunit). HCG acts almost like the body's own luteinizing hormone (LH): it plugs into the LH receptor on the testes and ovaries and tells them to make sex hormones — androgens (testosterone) in men and progesterone in women. Because it mimics LH so closely, it is used to trigger ovulation, to stimulate testosterone and sperm production, and to help undescended testicles drop in boys. In pregnancy it keeps the corpus luteum producing progesterone so the pregnancy is maintained, and it is the molecule detected by pregnancy tests. Regulatory labels are explicit that HCG has no known effect on fat, appetite or body-fat distribution and has not been shown to help weight loss.
Vendor and review sources describe humanin as a small peptide encoded within the mitochondrial genome that acts as a 'mitokine' (vendor claim) — a signal that mitochondria send to the rest of the body when under stress. Sources report it works by latching onto cell-surface receptors and by blocking proteins inside the cell that would otherwise trigger cell death, and that its levels naturally decline with age. In cell and animal studies it is reported to protect neurons, heart and other cells from damage and to improve how the body handles insulin and glucose. A widely studied engineered version called HNG (the S14G analog) is reported to be about 1,000-fold more potent than the natural peptide in cell culture. Importantly, no human trials of giving humanin as a drug have been published.
Imunofan is a small synthetic peptide modeled on a fragment of thymopoietin, a natural thymic hormone that guides the development and activity of immune T-cells. Rather than simply revving up the immune system, it is described as an immunomodulator that nudges abnormal immune parameters back toward balance — boosting defenses when they are weak and calming them when they are overactive. It is reported to act in three overlapping stages: within a few hours it activates the body's antioxidant defenses (scavenging reactive oxygen species and raising glutathione); over the following days to weeks it enhances the activity of immune cells such as neutrophils, macrophages, NK cells and B-cells; and over months it helps normalize the ratio of T-cell subtypes and consolidate immune memory. It is also credited with antioxidant and liver-protective actions and with stimulating tissue repair.
Kisspeptin-10 is a short 10-amino-acid fragment of the natural kisspeptin hormone that acts as a full activator (agonist) of the KISS1R receptor (also called GPR54) found on the GnRH neurons of the hypothalamus. By switching on these neurons, it triggers release of GnRH, which in turn prompts the pituitary to secrete the reproductive hormones LH and FSH. LH then stimulates testosterone production in men and progesterone/estradiol in women, while FSH supports sperm and egg development. In short, kisspeptin-10 sits at the top of the reproductive hormone cascade and 'kick-starts' it. Its effect depends heavily on how it is given: brief pulses stimulate the system, whereas continuous over-stimulation can, according to some sources, desensitize the receptor and instead suppress hormone output. Its effects also differ between the sexes and across the menstrual cycle.
Klotho is a protein the body makes naturally, mostly in the kidney but also in the brain and pancreas, and reviews describe its levels as declining with age. It exists as a membrane-bound form and as a soluble form that circulates like a hormone. Reviews report that the membrane form works together with FGF23 to help the kidney manage phosphate and vitamin D, while the soluble form is described as having anti-inflammatory, anti-oxidative, and anti-scarring (antifibrotic) actions. Observational human studies associate higher Klotho with better cognition, lower dementia rates, and protection against kidney and cardiovascular disease, and animal studies report that adding Klotho can boost cognition and extend lifespan. Importantly, one primate study found a low dose helped memory while a high dose did not, and multiple sources caution that too much Klotho could disturb calcium and phosphate balance.
LL-37 is described by sources as the only human cathelicidin — a 37-amino-acid, positively charged peptide cut from a precursor protein called hCAP-18. Because it carries a positive charge, it is drawn to the negatively charged surfaces of bacteria, where a Tier-1 review reports it punches holes in and permeabilizes microbial membranes, killing many bacteria (gram-positive and gram-negative), some fungi, and some viruses. Beyond killing microbes directly, sources describe it as an immune-signaling molecule: it binds and neutralizes bacterial endotoxin, recruits immune cells, and can dissolve bacterial biofilms and drive neutrophils to release DNA nets. Reviews stress that it has both anti- and pro-inflammatory effects and can be both protective and harmful depending on context — it is also cytotoxic to human cells at higher concentrations and has been implicated in diseases such as psoriasis and lupus. In wound healing, sources report it promotes new blood-vessel growth and skin-cell migration.
Matrixyl is the trade name for palmitoyl pentapeptide-4 (Pal-KTTKS), a lab-made peptide made by attaching a fatty acid (palmitic acid) to a five-amino-acid chain (KTTKS) originally found as a fragment of type I collagen. It acts as a 'matrikine' — a messenger peptide that signals skin cells called fibroblasts to behave as if collagen has been damaged and needs rebuilding. In response, fibroblasts increase production of collagen, fibronectin, and other components of the skin's supportive matrix. The attached fatty acid makes the otherwise water-loving peptide able to slip through the skin's oily outer barrier to reach the dermis. In human trials this translates into modest, measurable reductions in wrinkles and improvements in skin texture and firmness, with very good tolerability.
MOTS-c is a small 16-amino-acid peptide that, according to vendor and review sources, is encoded inside mitochondrial DNA and was discovered in 2015 (vendor claim). Several sources describe it as a 'mitokine' — a signal that reports on mitochondrial health. Its most studied action, per multiple sources, is switching on AMPK, a cellular energy sensor that tells cells to burn fuel more efficiently, become more sensitive to insulin, and resist storing energy as fat. Under stress (low glucose, oxidative stress) sources report the peptide moves into the cell nucleus and turns on antioxidant and adaptive stress-response genes. Because exercise naturally raises MOTS-c and the peptide reproduces several exercise-like effects in animals, sources frequently describe it as an 'exercise-mimetic.'
According to peptide information sources, Palmitoyl Tripeptide-1 (Pal-GHK) is the small collagen-fragment peptide GHK (glycine-histidine-lysine) with a fatty (palmitic acid) tail attached to its N-terminus. Sources explain that GHK is naturally released when type I collagen breaks down and acts as a 'matrikine' — a signal that tells skin fibroblast cells to make new collagen and other matrix components. The fatty tail is described as a delivery vehicle that helps the otherwise water-loving peptide cross the oily outer skin barrier. Reference and reference-cited studies report that, in lab-grown skin cells, the peptide stimulates collagen and elastin production, appears to work through the TGF-β signaling pathway, and may reduce inflammation. Several sources stress that Pal-GHK is a copper-free analog and, unlike GHK-Cu, does not deliver copper ions.
Reviews describe pidotimod as a synthetic dipeptide that acts as an immune-system modulator, working on both innate and adaptive immunity. According to these reviews and human observational sources, it stimulates dendritic cells, boosts toll-like receptor (TLR) expression, and promotes production of signaling molecules such as IL-2 and IFN-gamma, thereby supporting both cell-based and antibody-based immune defenses. In vitro studies report it pushes T lymphocytes toward a Th1 phenotype, raises natural killer cell activity, and increases antibody levels including salivary IgA.
Vendor and educational guides describe PTD-DBM as a synthetic peptide designed to switch a natural brake back off inside hair-follicle cells (vendor claim). According to these sources, the Wnt/beta-catenin pathway drives hair-follicle growth and regeneration, and a protein called CXXC5 normally acts as a brake on that pathway by binding to a signaling protein called Dishevelled (Dvl). PTD-DBM is described as carrying a Dvl-binding fragment into cells (using a cell-penetrating carrier segment) where it competes with CXXC5 for Dvl, freeing Dvl to reactivate Wnt signaling and, in mouse studies, stimulating hair regrowth and even the formation of new follicles. Sources note that in androgenetic alopecia the DHT→PGD2→CXXC5 axis raises CXXC5 and suppresses this pathway, and that PTD-DBM is proposed to reverse that suppression. Nearly all direct efficacy evidence to date comes from mice and cultured cells.
Selank is a lab-made seven-amino-acid peptide built from tuftsin, a natural immune-signaling fragment of human antibody (IgG), with a short tail added to make it last longer in the body. Sources describe it as producing calming (anxiolytic), memory-supporting (nootropic) and immune-modulating effects. Rather than binding the same site as Valium-type drugs, animal studies report it fine-tunes the brain's main calming system (GABA) indirectly, nudges serotonin and dopamine activity, boosts growth factors like BDNF, and slows the breakdown of the body's own pain- and mood-regulating enkephalins. Reviews note its overall profile resembles low-dose tranquilizers but is reported without the amnesia, withdrawal or dependence that accompany benzodiazepines.
Semax is a lab-made short peptide (seven amino acids) based on a fragment of the natural hormone ACTH, with an added 'Pro-Gly-Pro' tail. It was designed to keep ACTH's brain-supporting and memory-enhancing effects while dropping its hormonal action, so unlike ACTH it does not push the adrenal glands to release cortisol. In animals it raises levels of brain growth factors (especially BDNF and NGF) and their TrkB receptor, and it nudges serotonin and dopamine signaling. After brain injury such as stroke, it appears to dial down inflammation and oxidative stress while turning on genes tied to nerve repair, new blood vessels, and neuron survival. In people it has mainly been studied for stroke recovery and for improving short-term memory and attention.
According to the source set, TB-500 is described as a lab-made version of thymosin beta-4, a small peptide that occurs naturally in nearly every human cell. Sources report its core action is grabbing hold of the cell's building-block protein actin, which lets cells move, migrate to injury sites and reorganize — processes tied to wound healing. Across animal and lab studies, sources describe it promoting new blood-vessel growth, calming inflammation and helping tissue repair. Two big cautions run through the sources: sources disagree on whether TB-500 is a short 7-amino-acid fragment or the full 43-amino-acid protein, and almost all human trial data actually used the full-length pharmaceutical protein rather than the fragment vendors sell — so whether the injected fragment itself works is genuinely disputed.
AOD-9604 is a small synthetic peptide copied from the tail end (C-terminal fragment) of human growth hormone—the portion thought to be responsible for growth hormone's fat-burning activity, separate from its growth-promoting and blood-sugar effects. It was designed to encourage the body to break down fat (lipolysis) and reduce the formation of new fat (lipogenesis) without raising blood glucose, suppressing the pituitary axis, or elevating IGF-1. Unlike full growth hormone, it does not meaningfully bind the classical growth hormone receptor or cause cell proliferation. Its fat effects appear linked to activity involving the beta-3 adrenergic receptor pathway in fat cells, though animal knockout studies suggest the effect is not directly mediated through that receptor.
Dihexa is a synthetic, metabolically stabilized peptide derived from angiotensin IV. Rather than acting on classic receptors directly, it is reported to bind hepatocyte growth factor (HGF) and boost HGF's activity at its receptor, c-Met. Turning on this HGF/c-Met pathway is thought to trigger the growth of new connections between brain cells — promoting dendritic spines and functional synapses — which researchers link to improved learning and memory in animals. It is described as extraordinarily potent at building synapses in cultured neurons and is orally active and able to cross the blood-brain barrier in rodents. Importantly, all of this comes from animal and cell studies, and some of the original foundational papers have been retracted for data problems.
Epithalon is a small synthetic four-amino-acid peptide (Ala-Glu-Asp-Gly) modeled on epithalamin, a natural extract from the pineal gland. Researchers report that it can switch on telomerase — the enzyme that maintains the protective caps (telomeres) on chromosomes — by increasing production of the hTERT component, and that in lab-grown human cells this lengthened telomeres and let cells divide past their usual limit. It is also studied as a regulator of the body clock, appearing to help restore normal nighttime melatonin production and circadian rhythms, and it acts as an antioxidant. At a deeper level it is proposed to enter the cell nucleus and interact directly with DNA and histone proteins to influence which genes are turned on or off.
Follistatin is a natural glycoprotein that acts as a 'blocker' of muscle-limiting signals. It grabs onto and neutralizes myostatin (GDF-8) and activin A — proteins that normally put the brakes on muscle growth and promote muscle wasting. By mopping these up before they can dock onto their receptors on muscle cells, follistatin removes that brake, which in animal and gene-therapy studies allows muscles to grow larger and stronger. It also originally came to light for its ability to reduce release of follicle-stimulating hormone (FSH) from the pituitary. Importantly, the dramatic muscle-growth results reported in the research come mostly from genetic overexpression or gene therapy that keeps follistatin present continuously — not from injecting the short-lived peptide.
Vendor and educational guides describe FOXO4-DRI as a synthetic peptide designed to selectively kill senescent ('zombie') cells (vendor claim) — cells that have stopped dividing but remain metabolically active and secrete inflammatory signals. According to these sources, senescent cells survive by using a protein called FOXO4 to hold the tumor-suppressor protein p53 captive in the nucleus, blocking p53's ability to trigger cell death. A vendor guide explains that FOXO4-DRI mimics the part of FOXO4 that binds p53, competitively displacing the real FOXO4 so that p53 is released and can move to the mitochondria to switch on the cell's self-destruct (apoptosis) program, specifically in senescent cells (vendor claim). The peptide is built from D-amino acids in a retro-inverso arrangement, which sources say roughly preserves its shape while making it resistant to the enzymes that would normally break peptides down.
Multiple sources describe GHK-Cu as the copper complex of a naturally occurring three-amino-acid peptide (glycine-histidine-lysine) bound to a copper(II) ion. Several sources report it was first isolated from human plasma in 1973 by Loren Pickart, who described it as a serum factor that made old cultured liver cells behave like younger ones. Sources note it occurs naturally in human plasma, saliva, and urine and is released when tissue is injured, and that endogenous levels are reported to decline with age (a 2022 review and other sources cite roughly 200 ng/mL at age 20 falling to about 80 ng/mL by age 60). The overall picture drawn by sources is that GHK-Cu delivers copper to cells, boosts collagen and other skin-matrix components, dampens inflammation, and switches many genes involved in repair, antioxidant defense, and tissue remodeling on or off — though one source cautions the headline '4,000+ genes' figure rests on a single unreplicated reanalysis.
GLOW is not a single drug but a community/wellness-market blend that combines three separately studied peptides — GHK-Cu, BPC-157, and TB-500 — marketed for skin quality and recovery. The idea is that each contributes to tissue repair from a different angle: GHK-Cu is a naturally occurring copper-carrying tripeptide that signals skin cells (fibroblasts) to make more collagen, elastin, and other building blocks while calming inflammation; BPC-157 is a fragment of a stomach protein that is proposed to promote new blood-vessel growth and speed healing of soft tissue and gut lining in animals; and TB-500 mimics part of thymosin beta-4 and helps repair cells migrate to injured areas. The claimed benefit of combining them — improved skin and faster recovery than any one alone — is based on theoretical synergy and practitioner reports, not on studies of the blend itself.
According to vendor and reference sources, KPV is a three-amino-acid fragment (Lys-Pro-Val) taken from the tail end of the natural hormone alpha-MSH, and most sources describe it as calming inflammation (vendor claim). A Tier 1 study using human airway cells reported that KPV dose-dependently dampened NF-κB — a master switch for inflammation — and reduced inflammatory molecules. Many sources say it enters cells (especially inflamed gut cells) via a transporter called PepT1 and quiets pro-inflammatory signals like TNF-alpha, IL-1beta and IL-6. Sources disagree on whether KPV works by activating melanocortin receptors or independently of them; several state it does NOT bind those receptors and therefore, they report, does not cause tanning or sexual side effects.
According to the sources, Leuphasyl (Pentapeptide-18) is a synthetic five-amino-acid peptide modeled on the body's own enkephalin opioid peptides. Reviews and vendor materials describe it as working like a topical, botox-like relaxant: it is reported to bind enkephalin/opioid receptors on the nerve side of the neuromuscular junction and dampen the release of acetylcholine, the signal that makes facial muscles contract (vendor claim). With less contraction of the muscles that create expression lines (such as around the eyebrows and eyes), sources report a reduction in the depth of expression wrinkles. Unlike botulinum toxin, several profiles note it acts at the receptor level upstream and is said to preserve partial muscle movement rather than freezing it. Sources describe it as applied topically in creams, gels, or serums, often combined with Argireline for a stronger effect.
According to Examine and an information site, Noopept is a synthetic dipeptide built as an analog of piracetam and based on the natural brain peptide cycloprolylglycine (vendor claim). Sources report that Noopept itself is broken down very quickly and is barely detectable in the body, and that it works largely as a prodrug — it is converted into cycloprolylglycine, which is thought to be responsible for its longer-lasting nootropic effects. Animal and cell studies attribute its cognitive and neuroprotective actions to raising the neurotrophic factors BDNF and NGF, boosting acetylcholine signaling, reducing oxidative stress and glutamate excitotoxicity, and increasing HIF-1 activity. Human observational and open-label Russian studies report improvements in memory, attention, and mood along with an anxiolytic effect in people with mild cognitive impairment, though sources stress the human evidence is thin.
P21 is a tiny, chemically stabilized fragment of ciliary neurotrophic factor (CNTF) designed to mimic CNTF's brain-protective effects while being small enough to cross into the brain and stable enough to survive oral or injected delivery. In animal studies it boosts the brain's own production of BDNF (a key growth factor), encourages the birth and maturation of new hippocampal neurons, strengthens synaptic connections, and reduces the abnormal 'tangling' (hyperphosphorylation) of the tau protein linked to Alzheimer's disease. Unlike full CNTF, it does not appear to suppress appetite or cause weight loss in animals. All of these findings are preclinical or anecdotal — there is no human trial data.
Palmitoyl tetrapeptide-7 is a lab-made peptide (the four amino acids Gly-Gln-Pro-Arg) attached to a fatty acid (palmitic acid). The fatty tail makes it more oil-loving so it can penetrate the skin's outer barrier and reach the deeper dermis. Its main reported action is calming chronic, low-grade inflammation in the skin by lowering the signaling molecule IL-6, which tends to rise with age and after UV exposure. By reducing this inflammatory signal, it is thought to help protect the skin's structural support (extracellular matrix) from breaking down. It is used almost exclusively as a topical anti-aging/skin-conditioning cosmetic ingredient, most famously as one of the two active peptides in the Matrixyl 3000 blend.
Sources describe Pinealon as a synthetic three-amino-acid peptide (Glu-Asp-Arg, abbreviated EDR) from the Russian 'peptide bioregulator' school associated with Vladimir Khavinson. Vendor and review sources propose that its main proposed action is entering cells and interacting directly with DNA to influence which genes are switched on, particularly genes tied to neuronal function, antioxidant defense and apoptosis (vendor claim). In-vitro and animal reports describe it limiting reactive-oxygen-species buildup and reducing cell death under oxidative stress and low-oxygen conditions, though sources caution that many of these mechanisms are theoretical and that its blood-brain-barrier penetration and proposed pineal/melatonin and serotonin effects have not been confirmed by receptor-binding studies. Notably, sources disagree on whether it is antioxidant or pro-oxidant.
SNAP-8 is a lab-made cosmetic peptide, an extended version of Argireline, designed to relax the small facial muscles that create expression lines. It is proposed to imitate part of a natural protein (SNAP-25) involved in nerve signaling, competing with that protein so the nerve releases less of the chemical (acetylcholine) that tells muscles to contract. The idea is that softer muscle contractions mean shallower dynamic wrinkles like crow's feet and forehead lines. Unlike Botox, it is described as a reversible competitor that relaxes rather than paralyzes muscles, so effects are subtler and fade when you stop using it. A major open question is whether such a large molecule can actually penetrate skin deeply enough to reach nerves.
Vendor and reference sources describe SYN-AKE as a small synthetic peptide designed to mimic Waglerin-1, a component of Temple Viper venom, in order to relax facial muscles and soften the appearance of expression wrinkles while still allowing normal expressions (vendor claim). According to these sources, it works by acting like a reversible plug at the receptor on muscle cells that normally receives the nerve signal to contract, so muscle cells stay more relaxed and expression lines are less deepened. DSM-Firmenich describes it as reducing the appearance of wrinkles and laughter lines. Multiple sources caution that independent validation is limited and that it is unproven whether a topically applied peptide actually reaches facial muscles millimeters below the skin.
Sources describe Thymalin as a polypeptide complex isolated from the thymus gland of young calves that acts as an immune regulator. Khavinson-group sources report it contains short peptides (the dipeptides EW and KE and the tripeptide EDP) that are said to bind DNA and histone proteins to influence which genes are switched on, thereby helping bone-marrow-derived precursor cells mature into T-lymphocytes and restoring balance to the immune system. Sources report it dampens pro-inflammatory signaling and enhances the activity of immune cells such as natural killer cells and phagocytes. Because it is a mixture rather than a single defined molecule, one vendor characterizes its effects as broader but less targeted than single-sequence peptides (vendor claim).
Reference profiles describe thymulin as a small nine-amino-acid hormone made by the epithelial cells of the thymus gland (vendor claim). Sources report that it only works when bound to zinc in a 1:1 ratio — the zinc-free form is described as biologically inactive, and in-vitro work reports that removing zinc with chelators abolishes activity while adding zinc back restores it. Sources report thymulin helps immature T-cells mature and differentiate, tunes the balance of T-cell subsets, boosts natural killer cell activity (an effect said to depend on adequate zinc), and dampens excessive inflammatory signaling. Because it needs zinc, sources report that serum thymulin drops in zinc deficiency and serves as a sensitive biomarker of zinc status. Profiles also note thymulin levels peak in childhood and fall with age as the thymus shrinks.
Vilon is one of the simplest possible bioregulators — a two-amino-acid peptide (lysine plus glutamic acid) developed within the Soviet-era Khavinson peptide bioregulator program. Its developers propose that, because it is so small, it can slip into the cell nucleus and bind specific DNA sequences to gently switch certain genes on or off, particularly genes involved in immunity and cell growth. In laboratory studies it appears to 'unwind' certain compacted regions of chromatin in cells from elderly people, reawakening some silenced genes, while leaving other regions untouched. In animals it has been reported to stimulate immune tissue, tune inflammatory signaling, prolong lifespan, and reduce the development of tumors. Importantly, the DNA-binding/epigenetic story is based mostly on computer modeling and cell-culture work, not confirmed in humans, and almost all of the evidence comes from a single research group.
| Compound | Evidence | Goals | Half-life |
|---|---|---|---|
| AfamelanotideAfamelanotide is a lab-made, longer-lasting version of a natural hormone (α-MSH) that tells pigment cells in the skin to make more of the dark protective pigment eumelanin. It does this by switching on the melanocortin-1 receptor (MC1R). The extra pigment builds up in the skin even without sun exposure, acting like a built-in sunscreen that reduces how much light penetrates. It also appears to boost the skin's antioxidant and DNA-repair defenses and to calm inflammation. In people with erythropoietic protoporphyria (EPP), this lets them tolerate more light and spend more pain-free time in sunlight. | Tier 1 |
|
Tiers run from 1 (human trials) to 4 (theoretical). How we grade evidence
| 15 h |
| BremelanotideBremelanotide is a lab-made version of a natural hormone (alpha-MSH) that acts in the brain rather than on blood vessels. It switches on melanocortin receptors (mainly MC4R, and also MC3R) in the hypothalamus, tuning brain circuits involved in sexual desire and arousal. By influencing dopamine-related pathways, it is thought to increase sexual motivation. This is different from erectile-dysfunction pills like sildenafil, which work on blood flow and nitric oxide in the penis. | Tier 1 |
| 2.7 h |
|---|
| CagrilintideAccording to Novo Nordisk development papers and reviews, cagrilintide is a long-acting synthetic version of amylin, a hormone the pancreas releases alongside insulin after meals to signal fullness. Consumer and pharmacy web material describe it as designed to activate amylin receptors in the brainstem, aiming to reduce appetite, boost fullness, slow the stomach's emptying, suppress the post-meal release of glucagon and help regulate blood sugar. It is engineered for once-weekly injection. Reviews note it is frequently combined with the GLP-1 drug semaglutide (as CagriSema) because the two work through separate routes, which sources describe as complementary and potentially additive for appetite reduction and glucose control. | Tier 1 |
| 180 h |
|---|
| CerebrolysinCerebrolysin is not a single molecule but a liquid preparation made from pig brain tissue, broken down by enzymes into a mix of free amino acids (roughly 75%) and small peptides under about 10,000 daltons (roughly 25%). These small components are thought to be able to cross into the brain and behave like the body's own natural nerve-growth signals (such as BDNF, NGF, GDNF and CNTF), helping nerve cells survive, form new connections, and grow. Researchers propose it protects neurons by reducing cell death, calming inflammation, lowering oxidative stress (free radicals), and supporting blood vessels in the brain. Because peptides are destroyed in the gut, it is given by injection or infusion rather than by mouth. It is approved in many countries for stroke, traumatic brain injury and dementia, but has never been approved by the U.S. FDA, and rigorous reviews disagree on how much real benefit it provides. | Tier 1 |
| — |
|---|
| CJC-1295According to Phase 1 trial reports and multiple reviews, CJC-1295 is a long-acting synthetic version of growth-hormone-releasing hormone (GHRH). Sources describe it as being built from the first 29 amino acids of natural GHRH with four amino-acid substitutions that make it resist breakdown by enzymes. The DAC (Drug Affinity Complex) version carries a chemical group that latches onto albumin, a blood protein, which sources say extends its active life from minutes to roughly a week. Reviews describe it binding the GHRH receptor on pituitary somatotroph cells to prompt the body's own growth hormone (GH) release, which in turn raises IGF-1. Sources emphasize that, unlike injecting GH directly, it amplifies the body's existing pulsatile GH pattern rather than replacing it. | Tier 1 |
| 168 h |
|---|
| CortexinCortexin is not a single molecule but a mixture of small water-soluble polypeptides (roughly 1,000–10,000 Da) extracted from the cerebral cortex of young cattle and pigs, along with amino acids and trace elements. It is proposed to act as a broad, multi-target neuroprotectant. Laboratory studies suggest its peptides bind to receptors that handle the brain's main excitatory (glutamate) and inhibitory (GABA) signaling, which could dampen overexcitation (excitotoxicity). It is also reported to protect neurons from damaging factors like glutamate excess, calcium overload, and free radicals, to reduce a step in the cell-death (apoptosis) cascade, to support the brain's antioxidant and anti-inflammatory balance, and to encourage nerve-cell survival, growth, and connections in ways compared to natural growth factors. It is claimed to help balance neurotransmitters (including dopamine and serotonin). It is used clinically in Russia and CIS countries as an injectable for stroke, brain injury, cognitive problems, and pediatric developmental issues, though independent reviewers judge the human evidence weak. | Tier 1 |
| — |
|---|
| DavunetideDavunetide (NAP) is a short 8-amino-acid piece of a natural brain protein called ADNP (activity-dependent neuroprotective protein). Its main proposed action is to help stabilize microtubules — the internal scaffolding of nerve cells — and to reduce abnormal phosphorylation of the tau protein that, when overloaded, forms toxic tangles seen in diseases like Alzheimer's. By binding to microtubule end-binding proteins and helping tau attach to microtubules, it is proposed to protect neurons from damage, prevent cell death, and support the growth of nerve fibers and synapses. Additional proposed effects include anti-inflammatory activity, antioxidant activity, and reducing protein aggregation. | Tier 1 |
| 1.2 h |
|---|
| ElafinElafin (also called Trappin-2 or SKALP) is described by DrugBank as a human protein made naturally in the skin, lung and breast that protects tissue from destruction by the immune system and blocks destructive enzymes involved in inflammation. A vendor profile and reviews describe it as an endogenous serine protease inhibitor produced by epithelial cells at mucosal surfaces that blocks neutrophil enzymes (elastase and proteinase 3) and also has direct antimicrobial activity against bacteria and fungi (vendor claim). Because the enzyme elastase is increased in pulmonary hypertension and inflammatory tissue damage, researchers have investigated giving extra elafin to dampen this damage. In its most rigorous human test — a randomised trial in heart-bypass surgery patients — elafin dramatically raised blood elafin levels and inhibited elastase but did not reduce heart-muscle injury over 48 hours. | Tier 1 |
| 6 h |
|---|
| HexarelinHexarelin is a synthetic six-amino-acid peptide that acts as a growth hormone secretagogue. It mimics the natural hormone ghrelin by binding to the growth hormone secretagogue receptor (GHS-R1a) on the pituitary gland, prompting a strong, pulsatile release of growth hormone. It also acts at the hypothalamus to boost GHRH activity and reduce somatostatin's braking effect. Because release stays pulsatile and subject to normal feedback, it tends to avoid continuously supra-physiologic GH levels. Beyond growth hormone, hexarelin engages a separate cardiac receptor (CD36) that produces heart-related effects independent of growth hormone, and it mildly stimulates cortisol, ACTH, and prolactin. | Tier 1 |
| 0.92 h |
|---|
| IpamorelinVendor and educational profiles describe ipamorelin (NNC 26-0161) as a synthetic five-amino-acid peptide that mimics the natural hunger hormone ghrelin by switching on the ghrelin receptor (GHSR-1a) in the pituitary gland and hypothalamus (vendor claim). According to these sources, this prompts the pituitary to release a pulse of growth hormone (GH), which in turn raises IGF-1 and is said to drive protein synthesis, fat breakdown and tissue repair. What multiple profiles emphasize is its selectivity: animal studies reported that ipamorelin releases GH without raising cortisol, prolactin, ACTH or other pituitary hormones, and expert commentary notes it does so while preserving the body's natural pulsatile GH rhythm rather than flooding the system with a constant elevation. | Tier 1 |
| 2 h |
|---|
| LactoferrinInvestigators describe lactoferrin as a natural iron-binding defence protein found in milk, tears, saliva, other body fluids and neutrophils, with a broad range of reported functions: killing microbes, calming inflammation, acting as an antioxidant and helping regulate cell growth and the immune system. Researchers report it works partly by sequestering the iron that many pathogens need to grow while sparing beneficial commensals such as lactobacilli and bifidobacteria, and partly through short positively charged sequences at its N-terminus that bind and disrupt microbial cell surfaces. Reviewers note that ingested lactoferrin is also taken up by cells through a receptor-mediated pathway that can influence gene transcription and immune function. The peptide fragment hLF1-11 represents the first 11 amino acids of human lactoferrin, which investigators say carry much of its antimicrobial and anti-inflammatory activity. | Tier 1 |
| — |
|---|
| Larazotide AcetateMultiple sources describe larazotide acetate (also called AT-1001 and INN-202) as a small, 8-amino-acid oral peptide that acts locally in the gut without being absorbed into the bloodstream. Reviews explain that in celiac disease, gluten triggers the release of a protein called zonulin, which loosens the 'tight junctions' between the cells lining the intestine, letting gluten fragments slip through and provoke an immune reaction. Reviews report that larazotide is thought to work as a zonulin antagonist — helping the tight junctions close and reassemble, so the gut barrier stays intact and gluten is kept from reaching the tissue underneath where it would spark inflammation. | Tier 1 |
| — |
|---|
| LinaclotideLinaclotide is a small 14-amino-acid peptide that mimics the body's natural guanylin hormones. Taken by mouth, it stays inside the gut and switches on a receptor called guanylate cyclase-C (GC-C) on the lining of the intestine. This raises a signaling molecule called cGMP, which prompts the gut to secrete chloride, bicarbonate, and fluid into the intestine. The extra fluid softens stool and speeds up movement through the bowel, relieving constipation. The rise in cGMP also appears to reduce gut pain signaling, which helps with the abdominal pain and bloating of IBS-C. Because it is barely absorbed into the bloodstream, its effects are almost entirely local to the intestine. | Tier 1 |
| 0.05 h |
|---|
| Melanotan IIMelanotan II is a lab-made, ring-shaped copy of the natural hormone alpha-MSH that our bodies use to signal skin pigment cells. It switches on melanocortin receptors (MC1R, MC3R, MC4R and MC5R), which raises a cell-signaling molecule called cyclic AMP. In the skin this ramps up production of the dark pigment eumelanin, tanning the skin even without sunlight and offering some UV protection. Because it also hits receptors in the brain, it can trigger erections and sexual desire, suppress appetite, and affect glands — effects that cannot be separated from the tanning effect because the peptide is non-selective. It is far more potent than the natural hormone and its ring structure makes it last longer than natural alpha-MSH before being broken down. | Tier 1 |
| 1 h |
|---|
| MK-677MK-677 (ibutamoren) is an orally active, non-peptide molecule that mimics the hunger hormone ghrelin. It switches on the ghrelin receptor (GHS-R1a) in the pituitary gland and hypothalamus, prompting the body to release more of its own growth hormone (GH), which in turn raises IGF-1. Unlike injected GH, it amplifies the body's natural pulsing pattern of GH release without shutting down the normal feedback system. Because it survives stomach digestion, it can be taken by mouth once daily and keeps GH and IGF-1 elevated for up to about 24 hours. Through the same ghrelin pathway it also increases appetite and can affect sleep, insulin sensitivity, and repair processes. | Tier 1 |
| 6 h |
|---|
| OxytocinOxytocin is a small nine-amino-acid hormone made in the hypothalamus and released from the posterior pituitary gland, as described across multiple reviews and the FDA prescribing information. Its best-established action, per the Pitocin label, is stimulating rhythmic contractions of the uterine smooth muscle by raising intracellular calcium, an effect that becomes strong toward the end of pregnancy when uterine receptors are most abundant. Beyond the uterus, reviews describe oxytocin acting in the brain as a 'prosocial' signaling molecule linked to social recognition, bonding, trust, empathy, stress responses and anxiety, though human behavioral findings are mixed and often fail to confirm effects seen in animals. | Tier 1 |
| 0.058 h |
|---|
| PlecanatidePlecanatide is a synthetic 16-amino-acid peptide that mimics a natural human hormone called uroguanylin. It works locally inside the gut by switching on a receptor (guanylate cyclase-C, or GC-C) on the surface of intestinal lining cells. This triggers the cells to pump chloride and bicarbonate into the intestine, which draws in more fluid, softens stool, and speeds up movement through the bowel. It is designed to stay in the gut and is barely absorbed into the bloodstream. Animal studies also suggest it can quiet pain-sensing nerves in the intestine. | Tier 1 |
| — |
|---|
| RetatrutideMultiple clinical trial reports describe retatrutide (LY3437943) as a single peptide that switches on three gut and metabolic hormone receptors at once: the GIP receptor, the GLP-1 receptor, and the glucagon receptor. According to Eli Lilly and mechanistic reviews, activating GLP-1 boosts glucose-dependent insulin release, slows stomach emptying and increases feelings of fullness; activating GIP also aids insulin release and lipid handling; and activating the glucagon receptor raises energy expenditure, thermogenesis and fat mobilization while reducing food intake. The combined result reported across trials is dose-dependent weight loss and improved blood-sugar control. A fatty diacid attached to the peptide extends its half-life to roughly 6 days, allowing once-weekly injection. | Tier 1 |
| 144 h |
|---|
| SemaglutideSemaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist that mimics the natural gut hormone GLP-1. It tells the pancreas to release more insulin and less glucagon, but only when blood sugar is elevated, which lowers blood glucose with a low risk of hypoglycemia. It also acts on appetite regulation and slows the rate at which the stomach empties, leading to reduced food intake and weight loss. | Tier 1 |
| 168 h |
|---|
| SermorelinSermorelin is a lab-made copy of the active part of the body's own growth hormone-releasing hormone (GHRH). Rather than supplying growth hormone directly, it signals the pituitary gland to make and release its own growth hormone in natural bursts. That released growth hormone then prompts the liver to produce IGF-1. Because it works within the body's normal feedback loops, growth hormone release stays pulsatile and is still held in check by the body's natural braking hormone, somatostatin. | Tier 1 |
| 0.19 h |
|---|
| SS-31SS-31 (elamipretide) is a small synthetic peptide that homes in on the powerhouses of the cell — the mitochondria. It carries a positive charge and rapidly penetrates cells, accumulating hundreds to thousands of times over inside the inner mitochondrial membrane. There it binds tightly to cardiolipin, a special fat found only in mitochondria that is essential for keeping the energy-producing machinery organized and working. By protecting cardiolipin, SS-31 helps preserve mitochondrial structure, keeps the electron transport chain assembled, boosts ATP (energy) production, and reduces harmful reactive oxygen species at their source rather than mopping them up after the fact. It has been studied in Barth syndrome, mitochondrial myopathy, heart failure, kidney injury, and age-related macular degeneration, and in September 2025 received FDA accelerated approval (as Forzinity) to improve muscle strength in Barth syndrome patients weighing at least 30 kg. | Tier 1 |
| 3.5 h |
|---|
| TeduglutideTeduglutide is a lab-made, longer-lasting copy of a natural gut hormone called GLP-2. Like the natural hormone, it tells the cells lining the intestine to grow, repair themselves and resist dying off. This makes the intestinal surface healthier and better able to absorb fluids and nutrients. It also slows how fast the stomach empties, reduces excess stomach acid, and boosts blood flow to the gut. In people with short bowel syndrome — who have lost a lot of functional intestine — these effects help the remaining bowel absorb more, so they need less nutrition delivered through an IV (parenteral support). | Tier 1 |
| 1.47 h |
|---|
| TesamorelinTesamorelin is a synthetic, stabilized version of growth hormone-releasing hormone (GHRH), the natural brain signal that tells the pituitary gland to release growth hormone. Rather than injecting growth hormone directly, tesamorelin prompts the body to release its own growth hormone in a natural, pulsing pattern. The extra growth hormone then drives the liver to make IGF-1 and promotes the breakdown of fat (lipolysis), which is why it reduces excess visceral (deep abdominal) fat in HIV-infected patients with lipodystrophy. | Tier 1 |
| — |
|---|
| Thymosin Alpha-1Thymosin alpha-1 is a 28-amino-acid peptide the thymus gland naturally makes; reviews describe it as long recognized for modifying, enhancing and restoring immune function. Sources report it helps train and coordinate immune cells — encouraging T cells to mature and specialize, activating natural killer cells and dendritic cells, and tuning the mix of signaling molecules (cytokines) the immune system releases. One web source attributes to it a dual capacity to both boost an underactive immune response and calm an overactive, inflammatory one. Much of this mechanistic picture comes from expert opinion, in vitro work and animal studies rather than human trials. | Tier 1 |
| 2 h |
|---|
| TirzepatideAccording to a Tier 1 review, tirzepatide is a once-weekly injectable that activates two gut-hormone receptors at once — the GIP receptor and the GLP-1 receptor (a 'dual incretin' agonist). A review explains that GIP and GLP-1 are incretin hormones the intestine releases after eating; they prompt the pancreas to release insulin when blood glucose is high, and GLP-1 also reduces food intake and slows stomach emptying. A peptide protocol wiki describes how GLP-1 receptor activation by tirzepatide boosts glucose-dependent insulin secretion, lowers glucagon, slows gastric emptying and reduces appetite through the hypothalamus, while GIP receptor activation adds to insulin secretion, may improve lipid metabolism and fat distribution, and enhances central appetite control (vendor claim). A pharmacokinetic study reports the glucose-lowering effect may reflect GIP-receptor-mediated insulin action plus improved insulin sensitivity independent of weight change, while weight loss reflects combined GIP- and GLP-1-mediated effects on satiety and food intake. | Tier 1 |
| 120 h |
|---|
| TriptorelinTriptorelin is a lab-made, more potent copy of the natural hormone (GnRH/LHRH) that tells the pituitary gland to release the reproductive hormones LH and FSH. When given continuously as a long-acting depot, it first causes a brief surge in these hormones (and in testosterone or estrogen) for a few weeks, then shuts the system down. This sustained shutdown drops testosterone in men to levels seen after surgical castration, and lowers estrogen in women, which is useful when a cancer or condition is fueled by sex hormones or when puberty needs to be paused. The effect wears off after the drug is stopped. | Tier 1 |
| 3 h |
|---|
| Alpha-MSHAlpha-MSH is a small, naturally occurring hormone (a 13-amino-acid peptide) that the body makes from a larger precursor protein called POMC. It is produced by skin cells after sun exposure and by the brain/pituitary. It works by switching on melanocortin receptors (MC1R, MC3R, MC4R, MC5R), which are found on many cell types. Through these receptors it drives skin tanning (melanin production), calms inflammation, dampens appetite (promotes feeling full), and influences glucose handling in muscle, immune activity, and sexual behavior. It binds MC1R most strongly, which is why pigment and anti-inflammatory effects are prominent. | Tier 2 |
| 0.25 h |
|---|
| ArgirelineArgireline is a small synthetic peptide designed to mimic part of a natural muscle-signaling protein (SNAP-25). By imitating this fragment, it is proposed to interfere with the machinery nerves use to release the chemical messenger (acetylcholine) that tells facial muscles to contract. The idea is that reducing these contractions softens the repeated creasing that forms expression lines, giving it a marketing reputation as a topical, needle-free alternative to Botox. Importantly, this mechanism is well supported in lab dishes but its relevance to topical cosmetic use is uncertain, because very little of the peptide actually penetrates the skin to reach facial muscles. | Tier 2 |
| — |
|---|
| BPC-157Several reviews describe BPC-157 as a synthetic 15-amino-acid peptide originally isolated from human gastric juice. Animal and in vitro studies report it promotes the growth of new blood vessels, helps cells migrate to repair tissue, and protects tissues from damage. Studies attribute these effects to its interaction with nitric oxide production and growth-factor signaling, and reviews report it appears especially effective in poorly-vascularized tissues such as tendons and ligaments. Almost all of this evidence is preclinical; human data are minimal. | Tier 2 |
| 0.5 h |
|---|
| DSIPDSIP (delta sleep-inducing peptide) is a small 9-amino-acid peptide first isolated from the blood of sleeping rabbits in the 1970s. It was named for its ability to increase deep, slow-wave (delta) sleep in animals. Despite decades of study, no specific DSIP receptor, gene, or precursor protein has ever been identified, so how it works remains unresolved. Rather than sedating like a sleeping pill, it appears to support natural sleep — increasing sleep depth and efficiency and creating a subjective feeling of sleep pressure without suppressing REM sleep or causing next-day grogginess. It seems to influence sleep indirectly through several brain systems (GABA, glutamate/NMDA, and opioid/enkephalin pathways), circadian rhythms, melatonin, and stress hormones, and it turns up in many tissues and body fluids. Its human sleep effects are strongest in people with disrupted sleep and modest in healthy sleepers. | Tier 2 |
| 0.25 h |
|---|
| GonadorelinGonadorelin is a lab-made copy of the body's own gonadotropin-releasing hormone (GnRH), the master hormone from the hypothalamus that tells the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH). These in turn drive the testes and ovaries to make sex hormones and support sperm and egg development. A crucial feature is timing: the natural hormone is released in pulses every 90-120 minutes, and delivering gonadorelin in matching pulses keeps the pituitary responsive. If instead it is given continuously, the pituitary receptors shut down and hormone output paradoxically falls. Because of this, it is used both as a single-dose diagnostic test of pituitary function and, via a programmable pump giving pulses, to induce ovulation or restore fertility in people whose own hypothalamus is not producing GnRH. | Tier 2 |
| 0.5 h |
|---|
| HCGHCG is a hormone normally made by the placenta during pregnancy. It is built from two pieces (an alpha subunit shared with the pituitary hormones LH, FSH and TSH, and a unique beta subunit). HCG acts almost like the body's own luteinizing hormone (LH): it plugs into the LH receptor on the testes and ovaries and tells them to make sex hormones — androgens (testosterone) in men and progesterone in women. Because it mimics LH so closely, it is used to trigger ovulation, to stimulate testosterone and sperm production, and to help undescended testicles drop in boys. In pregnancy it keeps the corpus luteum producing progesterone so the pregnancy is maintained, and it is the molecule detected by pregnancy tests. Regulatory labels are explicit that HCG has no known effect on fat, appetite or body-fat distribution and has not been shown to help weight loss. | Tier 2 |
| 30 h |
|---|
| HumaninVendor and review sources describe humanin as a small peptide encoded within the mitochondrial genome that acts as a 'mitokine' (vendor claim) — a signal that mitochondria send to the rest of the body when under stress. Sources report it works by latching onto cell-surface receptors and by blocking proteins inside the cell that would otherwise trigger cell death, and that its levels naturally decline with age. In cell and animal studies it is reported to protect neurons, heart and other cells from damage and to improve how the body handles insulin and glucose. A widely studied engineered version called HNG (the S14G analog) is reported to be about 1,000-fold more potent than the natural peptide in cell culture. Importantly, no human trials of giving humanin as a drug have been published. | Tier 2 |
| 0.5 h |
|---|
| ImunofanImunofan is a small synthetic peptide modeled on a fragment of thymopoietin, a natural thymic hormone that guides the development and activity of immune T-cells. Rather than simply revving up the immune system, it is described as an immunomodulator that nudges abnormal immune parameters back toward balance — boosting defenses when they are weak and calming them when they are overactive. It is reported to act in three overlapping stages: within a few hours it activates the body's antioxidant defenses (scavenging reactive oxygen species and raising glutathione); over the following days to weeks it enhances the activity of immune cells such as neutrophils, macrophages, NK cells and B-cells; and over months it helps normalize the ratio of T-cell subtypes and consolidate immune memory. It is also credited with antioxidant and liver-protective actions and with stimulating tissue repair. | Tier 2 |
| 1 h |
|---|
| Kisspeptin-10Kisspeptin-10 is a short 10-amino-acid fragment of the natural kisspeptin hormone that acts as a full activator (agonist) of the KISS1R receptor (also called GPR54) found on the GnRH neurons of the hypothalamus. By switching on these neurons, it triggers release of GnRH, which in turn prompts the pituitary to secrete the reproductive hormones LH and FSH. LH then stimulates testosterone production in men and progesterone/estradiol in women, while FSH supports sperm and egg development. In short, kisspeptin-10 sits at the top of the reproductive hormone cascade and 'kick-starts' it. Its effect depends heavily on how it is given: brief pulses stimulate the system, whereas continuous over-stimulation can, according to some sources, desensitize the receptor and instead suppress hormone output. Its effects also differ between the sexes and across the menstrual cycle. | Tier 2 |
| 0.0667 h |
|---|
| KlothoKlotho is a protein the body makes naturally, mostly in the kidney but also in the brain and pancreas, and reviews describe its levels as declining with age. It exists as a membrane-bound form and as a soluble form that circulates like a hormone. Reviews report that the membrane form works together with FGF23 to help the kidney manage phosphate and vitamin D, while the soluble form is described as having anti-inflammatory, anti-oxidative, and anti-scarring (antifibrotic) actions. Observational human studies associate higher Klotho with better cognition, lower dementia rates, and protection against kidney and cardiovascular disease, and animal studies report that adding Klotho can boost cognition and extend lifespan. Importantly, one primate study found a low dose helped memory while a high dose did not, and multiple sources caution that too much Klotho could disturb calcium and phosphate balance. | Tier 2 |
| 12 h |
|---|
| LL-37LL-37 is described by sources as the only human cathelicidin — a 37-amino-acid, positively charged peptide cut from a precursor protein called hCAP-18. Because it carries a positive charge, it is drawn to the negatively charged surfaces of bacteria, where a Tier-1 review reports it punches holes in and permeabilizes microbial membranes, killing many bacteria (gram-positive and gram-negative), some fungi, and some viruses. Beyond killing microbes directly, sources describe it as an immune-signaling molecule: it binds and neutralizes bacterial endotoxin, recruits immune cells, and can dissolve bacterial biofilms and drive neutrophils to release DNA nets. Reviews stress that it has both anti- and pro-inflammatory effects and can be both protective and harmful depending on context — it is also cytotoxic to human cells at higher concentrations and has been implicated in diseases such as psoriasis and lupus. In wound healing, sources report it promotes new blood-vessel growth and skin-cell migration. | Tier 2 |
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| MatrixylMatrixyl is the trade name for palmitoyl pentapeptide-4 (Pal-KTTKS), a lab-made peptide made by attaching a fatty acid (palmitic acid) to a five-amino-acid chain (KTTKS) originally found as a fragment of type I collagen. It acts as a 'matrikine' — a messenger peptide that signals skin cells called fibroblasts to behave as if collagen has been damaged and needs rebuilding. In response, fibroblasts increase production of collagen, fibronectin, and other components of the skin's supportive matrix. The attached fatty acid makes the otherwise water-loving peptide able to slip through the skin's oily outer barrier to reach the dermis. In human trials this translates into modest, measurable reductions in wrinkles and improvements in skin texture and firmness, with very good tolerability. | Tier 2 |
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| MOTS-cMOTS-c is a small 16-amino-acid peptide that, according to vendor and review sources, is encoded inside mitochondrial DNA and was discovered in 2015 (vendor claim). Several sources describe it as a 'mitokine' — a signal that reports on mitochondrial health. Its most studied action, per multiple sources, is switching on AMPK, a cellular energy sensor that tells cells to burn fuel more efficiently, become more sensitive to insulin, and resist storing energy as fat. Under stress (low glucose, oxidative stress) sources report the peptide moves into the cell nucleus and turns on antioxidant and adaptive stress-response genes. Because exercise naturally raises MOTS-c and the peptide reproduces several exercise-like effects in animals, sources frequently describe it as an 'exercise-mimetic.' | Tier 2 |
| — |
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| Palmitoyl Tripeptide-1According to peptide information sources, Palmitoyl Tripeptide-1 (Pal-GHK) is the small collagen-fragment peptide GHK (glycine-histidine-lysine) with a fatty (palmitic acid) tail attached to its N-terminus. Sources explain that GHK is naturally released when type I collagen breaks down and acts as a 'matrikine' — a signal that tells skin fibroblast cells to make new collagen and other matrix components. The fatty tail is described as a delivery vehicle that helps the otherwise water-loving peptide cross the oily outer skin barrier. Reference and reference-cited studies report that, in lab-grown skin cells, the peptide stimulates collagen and elastin production, appears to work through the TGF-β signaling pathway, and may reduce inflammation. Several sources stress that Pal-GHK is a copper-free analog and, unlike GHK-Cu, does not deliver copper ions. | Tier 2 |
| 7 h |
|---|
| PidotimodReviews describe pidotimod as a synthetic dipeptide that acts as an immune-system modulator, working on both innate and adaptive immunity. According to these reviews and human observational sources, it stimulates dendritic cells, boosts toll-like receptor (TLR) expression, and promotes production of signaling molecules such as IL-2 and IFN-gamma, thereby supporting both cell-based and antibody-based immune defenses. In vitro studies report it pushes T lymphocytes toward a Th1 phenotype, raises natural killer cell activity, and increases antibody levels including salivary IgA. | Tier 2 |
| 4 h |
|---|
| PTD-DBMVendor and educational guides describe PTD-DBM as a synthetic peptide designed to switch a natural brake back off inside hair-follicle cells (vendor claim). According to these sources, the Wnt/beta-catenin pathway drives hair-follicle growth and regeneration, and a protein called CXXC5 normally acts as a brake on that pathway by binding to a signaling protein called Dishevelled (Dvl). PTD-DBM is described as carrying a Dvl-binding fragment into cells (using a cell-penetrating carrier segment) where it competes with CXXC5 for Dvl, freeing Dvl to reactivate Wnt signaling and, in mouse studies, stimulating hair regrowth and even the formation of new follicles. Sources note that in androgenetic alopecia the DHT→PGD2→CXXC5 axis raises CXXC5 and suppresses this pathway, and that PTD-DBM is proposed to reverse that suppression. Nearly all direct efficacy evidence to date comes from mice and cultured cells. | Tier 2 |
| 2 h |
|---|
| SelankSelank is a lab-made seven-amino-acid peptide built from tuftsin, a natural immune-signaling fragment of human antibody (IgG), with a short tail added to make it last longer in the body. Sources describe it as producing calming (anxiolytic), memory-supporting (nootropic) and immune-modulating effects. Rather than binding the same site as Valium-type drugs, animal studies report it fine-tunes the brain's main calming system (GABA) indirectly, nudges serotonin and dopamine activity, boosts growth factors like BDNF, and slows the breakdown of the body's own pain- and mood-regulating enkephalins. Reviews note its overall profile resembles low-dose tranquilizers but is reported without the amnesia, withdrawal or dependence that accompany benzodiazepines. | Tier 2 |
| 0.04 h |
|---|
| SemaxSemax is a lab-made short peptide (seven amino acids) based on a fragment of the natural hormone ACTH, with an added 'Pro-Gly-Pro' tail. It was designed to keep ACTH's brain-supporting and memory-enhancing effects while dropping its hormonal action, so unlike ACTH it does not push the adrenal glands to release cortisol. In animals it raises levels of brain growth factors (especially BDNF and NGF) and their TrkB receptor, and it nudges serotonin and dopamine signaling. After brain injury such as stroke, it appears to dial down inflammation and oxidative stress while turning on genes tied to nerve repair, new blood vessels, and neuron survival. In people it has mainly been studied for stroke recovery and for improving short-term memory and attention. | Tier 2 |
| — |
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| TB-500According to the source set, TB-500 is described as a lab-made version of thymosin beta-4, a small peptide that occurs naturally in nearly every human cell. Sources report its core action is grabbing hold of the cell's building-block protein actin, which lets cells move, migrate to injury sites and reorganize — processes tied to wound healing. Across animal and lab studies, sources describe it promoting new blood-vessel growth, calming inflammation and helping tissue repair. Two big cautions run through the sources: sources disagree on whether TB-500 is a short 7-amino-acid fragment or the full 43-amino-acid protein, and almost all human trial data actually used the full-length pharmaceutical protein rather than the fragment vendors sell — so whether the injected fragment itself works is genuinely disputed. | Tier 2 |
| 4 h |
|---|
| AOD-9604AOD-9604 is a small synthetic peptide copied from the tail end (C-terminal fragment) of human growth hormone—the portion thought to be responsible for growth hormone's fat-burning activity, separate from its growth-promoting and blood-sugar effects. It was designed to encourage the body to break down fat (lipolysis) and reduce the formation of new fat (lipogenesis) without raising blood glucose, suppressing the pituitary axis, or elevating IGF-1. Unlike full growth hormone, it does not meaningfully bind the classical growth hormone receptor or cause cell proliferation. Its fat effects appear linked to activity involving the beta-3 adrenergic receptor pathway in fat cells, though animal knockout studies suggest the effect is not directly mediated through that receptor. | Tier 3 |
| 0.5 h |
|---|
| DihexaDihexa is a synthetic, metabolically stabilized peptide derived from angiotensin IV. Rather than acting on classic receptors directly, it is reported to bind hepatocyte growth factor (HGF) and boost HGF's activity at its receptor, c-Met. Turning on this HGF/c-Met pathway is thought to trigger the growth of new connections between brain cells — promoting dendritic spines and functional synapses — which researchers link to improved learning and memory in animals. It is described as extraordinarily potent at building synapses in cultured neurons and is orally active and able to cross the blood-brain barrier in rodents. Importantly, all of this comes from animal and cell studies, and some of the original foundational papers have been retracted for data problems. | Tier 3 |
| 304.8 h |
|---|
| EpithalonEpithalon is a small synthetic four-amino-acid peptide (Ala-Glu-Asp-Gly) modeled on epithalamin, a natural extract from the pineal gland. Researchers report that it can switch on telomerase — the enzyme that maintains the protective caps (telomeres) on chromosomes — by increasing production of the hTERT component, and that in lab-grown human cells this lengthened telomeres and let cells divide past their usual limit. It is also studied as a regulator of the body clock, appearing to help restore normal nighttime melatonin production and circadian rhythms, and it acts as an antioxidant. At a deeper level it is proposed to enter the cell nucleus and interact directly with DNA and histone proteins to influence which genes are turned on or off. | Tier 3 |
| 0.5 h |
|---|
| Follistatin-344Follistatin is a natural glycoprotein that acts as a 'blocker' of muscle-limiting signals. It grabs onto and neutralizes myostatin (GDF-8) and activin A — proteins that normally put the brakes on muscle growth and promote muscle wasting. By mopping these up before they can dock onto their receptors on muscle cells, follistatin removes that brake, which in animal and gene-therapy studies allows muscles to grow larger and stronger. It also originally came to light for its ability to reduce release of follicle-stimulating hormone (FSH) from the pituitary. Importantly, the dramatic muscle-growth results reported in the research come mostly from genetic overexpression or gene therapy that keeps follistatin present continuously — not from injecting the short-lived peptide. | Tier 3 |
| 2 h |
|---|
| FOXO4-DRIVendor and educational guides describe FOXO4-DRI as a synthetic peptide designed to selectively kill senescent ('zombie') cells (vendor claim) — cells that have stopped dividing but remain metabolically active and secrete inflammatory signals. According to these sources, senescent cells survive by using a protein called FOXO4 to hold the tumor-suppressor protein p53 captive in the nucleus, blocking p53's ability to trigger cell death. A vendor guide explains that FOXO4-DRI mimics the part of FOXO4 that binds p53, competitively displacing the real FOXO4 so that p53 is released and can move to the mitochondria to switch on the cell's self-destruct (apoptosis) program, specifically in senescent cells (vendor claim). The peptide is built from D-amino acids in a retro-inverso arrangement, which sources say roughly preserves its shape while making it resistant to the enzymes that would normally break peptides down. | Tier 3 |
| 48 h |
|---|
| GHK-CuMultiple sources describe GHK-Cu as the copper complex of a naturally occurring three-amino-acid peptide (glycine-histidine-lysine) bound to a copper(II) ion. Several sources report it was first isolated from human plasma in 1973 by Loren Pickart, who described it as a serum factor that made old cultured liver cells behave like younger ones. Sources note it occurs naturally in human plasma, saliva, and urine and is released when tissue is injured, and that endogenous levels are reported to decline with age (a 2022 review and other sources cite roughly 200 ng/mL at age 20 falling to about 80 ng/mL by age 60). The overall picture drawn by sources is that GHK-Cu delivers copper to cells, boosts collagen and other skin-matrix components, dampens inflammation, and switches many genes involved in repair, antioxidant defense, and tissue remodeling on or off — though one source cautions the headline '4,000+ genes' figure rests on a single unreplicated reanalysis. | Tier 3 |
| 0.75 h |
|---|
| GLOWGLOW is not a single drug but a community/wellness-market blend that combines three separately studied peptides — GHK-Cu, BPC-157, and TB-500 — marketed for skin quality and recovery. The idea is that each contributes to tissue repair from a different angle: GHK-Cu is a naturally occurring copper-carrying tripeptide that signals skin cells (fibroblasts) to make more collagen, elastin, and other building blocks while calming inflammation; BPC-157 is a fragment of a stomach protein that is proposed to promote new blood-vessel growth and speed healing of soft tissue and gut lining in animals; and TB-500 mimics part of thymosin beta-4 and helps repair cells migrate to injured areas. The claimed benefit of combining them — improved skin and faster recovery than any one alone — is based on theoretical synergy and practitioner reports, not on studies of the blend itself. | Tier 3 |
| — |
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| KPVAccording to vendor and reference sources, KPV is a three-amino-acid fragment (Lys-Pro-Val) taken from the tail end of the natural hormone alpha-MSH, and most sources describe it as calming inflammation (vendor claim). A Tier 1 study using human airway cells reported that KPV dose-dependently dampened NF-κB — a master switch for inflammation — and reduced inflammatory molecules. Many sources say it enters cells (especially inflamed gut cells) via a transporter called PepT1 and quiets pro-inflammatory signals like TNF-alpha, IL-1beta and IL-6. Sources disagree on whether KPV works by activating melanocortin receptors or independently of them; several state it does NOT bind those receptors and therefore, they report, does not cause tanning or sexual side effects. | Tier 3 |
| — |
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| LeuphasylAccording to the sources, Leuphasyl (Pentapeptide-18) is a synthetic five-amino-acid peptide modeled on the body's own enkephalin opioid peptides. Reviews and vendor materials describe it as working like a topical, botox-like relaxant: it is reported to bind enkephalin/opioid receptors on the nerve side of the neuromuscular junction and dampen the release of acetylcholine, the signal that makes facial muscles contract (vendor claim). With less contraction of the muscles that create expression lines (such as around the eyebrows and eyes), sources report a reduction in the depth of expression wrinkles. Unlike botulinum toxin, several profiles note it acts at the receptor level upstream and is said to preserve partial muscle movement rather than freezing it. Sources describe it as applied topically in creams, gels, or serums, often combined with Argireline for a stronger effect. | Tier 3 |
| — |
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| NoopeptAccording to Examine and an information site, Noopept is a synthetic dipeptide built as an analog of piracetam and based on the natural brain peptide cycloprolylglycine (vendor claim). Sources report that Noopept itself is broken down very quickly and is barely detectable in the body, and that it works largely as a prodrug — it is converted into cycloprolylglycine, which is thought to be responsible for its longer-lasting nootropic effects. Animal and cell studies attribute its cognitive and neuroprotective actions to raising the neurotrophic factors BDNF and NGF, boosting acetylcholine signaling, reducing oxidative stress and glutamate excitotoxicity, and increasing HIF-1 activity. Human observational and open-label Russian studies report improvements in memory, attention, and mood along with an anxiolytic effect in people with mild cognitive impairment, though sources stress the human evidence is thin. | Tier 3 |
| 0.27 h |
|---|
| P21P21 is a tiny, chemically stabilized fragment of ciliary neurotrophic factor (CNTF) designed to mimic CNTF's brain-protective effects while being small enough to cross into the brain and stable enough to survive oral or injected delivery. In animal studies it boosts the brain's own production of BDNF (a key growth factor), encourages the birth and maturation of new hippocampal neurons, strengthens synaptic connections, and reduces the abnormal 'tangling' (hyperphosphorylation) of the tau protein linked to Alzheimer's disease. Unlike full CNTF, it does not appear to suppress appetite or cause weight loss in animals. All of these findings are preclinical or anecdotal — there is no human trial data. | Tier 3 |
| — |
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| Palmitoyl Tetrapeptide-7Palmitoyl tetrapeptide-7 is a lab-made peptide (the four amino acids Gly-Gln-Pro-Arg) attached to a fatty acid (palmitic acid). The fatty tail makes it more oil-loving so it can penetrate the skin's outer barrier and reach the deeper dermis. Its main reported action is calming chronic, low-grade inflammation in the skin by lowering the signaling molecule IL-6, which tends to rise with age and after UV exposure. By reducing this inflammatory signal, it is thought to help protect the skin's structural support (extracellular matrix) from breaking down. It is used almost exclusively as a topical anti-aging/skin-conditioning cosmetic ingredient, most famously as one of the two active peptides in the Matrixyl 3000 blend. | Tier 3 |
| — |
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| PinealonSources describe Pinealon as a synthetic three-amino-acid peptide (Glu-Asp-Arg, abbreviated EDR) from the Russian 'peptide bioregulator' school associated with Vladimir Khavinson. Vendor and review sources propose that its main proposed action is entering cells and interacting directly with DNA to influence which genes are switched on, particularly genes tied to neuronal function, antioxidant defense and apoptosis (vendor claim). In-vitro and animal reports describe it limiting reactive-oxygen-species buildup and reducing cell death under oxidative stress and low-oxygen conditions, though sources caution that many of these mechanisms are theoretical and that its blood-brain-barrier penetration and proposed pineal/melatonin and serotonin effects have not been confirmed by receptor-binding studies. Notably, sources disagree on whether it is antioxidant or pro-oxidant. | Tier 3 |
| — |
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| SNAP-8SNAP-8 is a lab-made cosmetic peptide, an extended version of Argireline, designed to relax the small facial muscles that create expression lines. It is proposed to imitate part of a natural protein (SNAP-25) involved in nerve signaling, competing with that protein so the nerve releases less of the chemical (acetylcholine) that tells muscles to contract. The idea is that softer muscle contractions mean shallower dynamic wrinkles like crow's feet and forehead lines. Unlike Botox, it is described as a reversible competitor that relaxes rather than paralyzes muscles, so effects are subtler and fade when you stop using it. A major open question is whether such a large molecule can actually penetrate skin deeply enough to reach nerves. | Tier 3 |
| — |
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| SYN-AKEVendor and reference sources describe SYN-AKE as a small synthetic peptide designed to mimic Waglerin-1, a component of Temple Viper venom, in order to relax facial muscles and soften the appearance of expression wrinkles while still allowing normal expressions (vendor claim). According to these sources, it works by acting like a reversible plug at the receptor on muscle cells that normally receives the nerve signal to contract, so muscle cells stay more relaxed and expression lines are less deepened. DSM-Firmenich describes it as reducing the appearance of wrinkles and laughter lines. Multiple sources caution that independent validation is limited and that it is unproven whether a topically applied peptide actually reaches facial muscles millimeters below the skin. | Tier 3 |
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| ThymalinSources describe Thymalin as a polypeptide complex isolated from the thymus gland of young calves that acts as an immune regulator. Khavinson-group sources report it contains short peptides (the dipeptides EW and KE and the tripeptide EDP) that are said to bind DNA and histone proteins to influence which genes are switched on, thereby helping bone-marrow-derived precursor cells mature into T-lymphocytes and restoring balance to the immune system. Sources report it dampens pro-inflammatory signaling and enhances the activity of immune cells such as natural killer cells and phagocytes. Because it is a mixture rather than a single defined molecule, one vendor characterizes its effects as broader but less targeted than single-sequence peptides (vendor claim). | Tier 3 |
| 7 h |
|---|
| ThymulinReference profiles describe thymulin as a small nine-amino-acid hormone made by the epithelial cells of the thymus gland (vendor claim). Sources report that it only works when bound to zinc in a 1:1 ratio — the zinc-free form is described as biologically inactive, and in-vitro work reports that removing zinc with chelators abolishes activity while adding zinc back restores it. Sources report thymulin helps immature T-cells mature and differentiate, tunes the balance of T-cell subsets, boosts natural killer cell activity (an effect said to depend on adequate zinc), and dampens excessive inflammatory signaling. Because it needs zinc, sources report that serum thymulin drops in zinc deficiency and serves as a sensitive biomarker of zinc status. Profiles also note thymulin levels peak in childhood and fall with age as the thymus shrinks. | Tier 3 |
| 0.17 h |
|---|
| VilonVilon is one of the simplest possible bioregulators — a two-amino-acid peptide (lysine plus glutamic acid) developed within the Soviet-era Khavinson peptide bioregulator program. Its developers propose that, because it is so small, it can slip into the cell nucleus and bind specific DNA sequences to gently switch certain genes on or off, particularly genes involved in immunity and cell growth. In laboratory studies it appears to 'unwind' certain compacted regions of chromatin in cells from elderly people, reawakening some silenced genes, while leaving other regions untouched. In animals it has been reported to stimulate immune tissue, tune inflammatory signaling, prolong lifespan, and reduce the development of tumors. Importantly, the DNA-binding/epigenetic story is based mostly on computer modeling and cell-culture work, not confirmed in humans, and almost all of the evidence comes from a single research group. | Tier 3 |
| 1.2 h |
|---|