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Peptide Atlas
All goals

Growth-hormone and fat-metabolism peptides for shifting body composition

Most compounds in this group aim to change body composition indirectly, by prompting the body to release more of its own growth hormone (GH), which then raises IGF-1 and encourages fat breakdown. A few act on separate pathways: some block muscle-limiting signals, others act directly on fat cells or on appetite. Human trials are strongest for growth-hormone-releasing agents and for one visceral-fat compound; much of the muscle-building evidence comes from animal work.

The biology of this goal

Building muscle while losing fat means changing the balance between two processes: making and keeping lean tissue, and storing versus burning fat. Growth hormone, made by the pituitary gland in the brain, sits at the center of this. When it is released it signals the liver to make a growth factor called IGF-1, which supports muscle, and it also encourages the body to break down stored fat. The body normally releases growth hormone in bursts and holds it in check with a braking hormone. Many of these compounds try to raise growth hormone by nudging the body's own release rather than injecting the hormone directly. Others skip the hormone system entirely: some remove a natural brake on muscle growth, some act straight on fat cells, and some reduce appetite through the brain.

What the research supports

11 of 18 compounds considered

Sermorelin

Tier 1 · Human trials

Human trials report that sermorelin stimulates pituitary GH secretion and treats growth failure in GH-deficient children, but the body-composition evidence for this goal is indirect.

Sermorelin is a lab-made copy of the active part of the body's own growth-hormone-releasing hormone (GHRH). Instead of supplying growth hormone directly, it signals the pituitary gland to release its own, which then prompts the liver to make IGF-1. Because it works inside the body's normal feedback loops, growth-hormone release stays in natural bursts.

  • Sermorelin is a 29-amino-acid analogue of human GHRH, the shortest synthetic peptide with full GHRH biological activity, and specifically stimulates GH secretion from the anterior pituitary.1

  • Growth hormone secretagogues, including GHRH-receptor agonists, were developed to treat or diagnose GH deficiency, which causes growth retardation and altered body composition.2

  • Once-daily subcutaneous sermorelin at bedtime is effective in treating some prepubertal children with idiopathic GH deficiency, sustaining height-velocity increases over 12 months.1

  • Sermorelin is a synthetic version of a naturally occurring substance that causes release of growth hormone from the pituitary gland.3

What this doesn't establish

The clinical data are in children with growth hormone deficiency for height gain and diagnosis; they do not establish muscle gain or fat loss in healthy adults seeking body-composition change.

MK-677

Tier 1 · Human trials

Human trials report sustained GH and IGF-1 elevation from MK-677, but the body-composition data specific to this goal are limited and come partly from a single low-tier case report.

MK-677 (ibutamoren) is a pill-form molecule that mimics the hunger hormone ghrelin, switching on its receptor in the pituitary and brain to raise the body's own growth hormone and IGF-1. Because it survives digestion, it can be taken by mouth once a day and keeps GH and IGF-1 raised for up to about 24 hours. Through the same pathway it also increases appetite.

  • MK-677 is a non-peptide, orally active GHS-R1a agonist that provides sustained GH and IGF-1 elevation for up to 24 hours from a single daily dose, with average IGF-1 elevation of 40–89% across clinical trials.4

  • In a single case report of co-administration with LGD-4033 over 5 weeks, total lean body mass rose 3.1%, trunk lean mass 6.6% and appendicular lean mass 4.3% — but total fat mass also rose 15.4%.5

  • Reported side effects of MK-677 include oedema, increased appetite and muscle pain, and one case of transaminitis (liver-enzyme elevation) that resolved after stopping.6

What this doesn't establish

The lean-mass figures come from one case report where MK-677 was co-administered with a selective androgen receptor modulator, and fat mass actually rose — so MK-677's independent muscle-and-fat effect is not established, and it carries appetite, oedema and liver-enzyme signals.

CJC-1295

Tier 1 · Human trials

Human trials report dose-dependent, sustained GH and IGF-1 increases from CJC-1295, with reviews attributing muscle-mass and strength effects, though the strongest body-composition claims sit in lower-tier sources.

CJC-1295 is a long-acting synthetic copy of growth-hormone-releasing hormone (GHRH). It attaches to a blood protein called albumin, which lets it keep prompting the body's own growth-hormone release for days rather than minutes. That raised growth hormone in turn increases IGF-1.

  • Subcutaneous CJC-1295 produced sustained, dose-dependent increases in GH and IGF-1 and is reported to restore circadian growth hormone and increase muscle mass and strength.7

  • CJC-1295 amplifies the existing pulsatile pattern of GH secretion (elevated pulse amplitude while retaining normal oscillation), rather than acting like exogenous GH.8

  • A single 60 µg/kg dose produced IGF-1 elevations lasting up to 14 days, with continued accumulation on repeated weekly dosing.8

  • Reported uses in FDA-submitted commentary include increased muscle mass, weight-loss support and thermogenic fat burning; most common side effects include flushing, injection-site reactions, edema, joint and muscle pain and fatigue.9

What this doesn't establish

The direct human endpoints are GH and IGF-1 pharmacology in healthy adults, not controlled muscle-gain or fat-loss outcomes; clinical development was halted after a participant death reportedly from a cardiovascular event.

Tesamorelin

Tier 1 · Human trials

Human trials report that tesamorelin reduces visceral fat and improves trunk fat and waist circumference in HIV-associated lipodystrophy, with dose-dependent IGF-1 elevation.

Tesamorelin is a stabilized synthetic version of growth-hormone-releasing hormone. It prompts the pituitary to release the body's own growth hormone in natural bursts, which raises IGF-1 and drives the breakdown of fat. It is approved specifically to reduce excess deep abdominal fat in HIV patients with a fat-redistribution condition called lipodystrophy.

  • Tesamorelin is a synthetic 44-amino-acid GHRH analogue that activates pituitary GHRH receptors, driving GH release and hepatic IGF-1 production, and is used to reduce visceral adiposity in HIV patients with lipodystrophy.10

  • In two well-designed 26-week trials it reduced visceral adipose tissue and improved trunk fat and waist circumference, with serious adverse events (mostly injection-site reactions, arthralgia, headache, peripheral edema) in under 4% of patients.11

  • Tesamorelin increases GH levels and raises IGF-1 dose-dependently in healthy subjects, and raises IGF-1 in HIV-infected patients.12

What this doesn't establish

Efficacy is established in HIV-associated visceral fat accumulation, not general muscle-building or fat loss in the wider population; VAT reaccumulates when treatment stops.

Follistatin-344

Tier 2 · Preclinical

Animal and laboratory studies suggest follistatin overexpression markedly increases muscle mass and reduces fat, but the strongest data rely on genetic/AAV delivery rather than peptide injection.

Follistatin is a natural protein that blocks myostatin — a signal that normally limits how much muscle the body builds. By grabbing and neutralizing myostatin before it can act, follistatin removes that brake, which in animal studies lets muscles grow larger. The dramatic muscle growth reported comes mostly from genetic and gene-therapy methods that keep follistatin present continuously, not from injecting the short-lived peptide.

  • Mice engineered to overexpress Fst specifically in muscle had at least twice the skeletal muscle mass of controls, and transgenic pigs showed increased skeletal muscle and reduced body fat.13

  • Transgenic F1 pigs had significantly higher lean-meat percentage (72.95% vs 69.18%) with myofiber hypertrophy and reduced Smad2 phosphorylation in muscle tissue.13

  • Follistatin physically wraps around myostatin in a high-affinity interaction, preventing it from reaching ActRIIB; a single AAV-delivered dose produced sustained muscle-mass increases exceeding 20% in mice lasting over 2 years.14

  • Myostatin (GDF-8) is a potent negative regulator of skeletal muscle mass, and natural myostatin-deficiency mutations across species produce a consistent phenotype of increased muscle and reduced adiposity.15

What this doesn't establish

There is no human trial evidence that injected follistatin-344 peptide builds muscle or reduces fat; the large effects come from genetic overexpression and gene therapy that maintain continuous exposure.

Hexarelin

Tier 1 · Human trials

Human trials report that intravenous hexarelin produces a substantial, dose-dependent rise in growth hormone in healthy men.

Hexarelin is a synthetic six-amino-acid peptide that mimics the hunger hormone ghrelin, binding its receptor on the pituitary to trigger a strong burst of growth-hormone release. In human dosing studies it raised growth hormone sharply and dose-dependently. Higher growth hormone is the route through which it could support fat breakdown and lean tissue.

  • Intravenous hexarelin produced dose-dependent GH increases, with mean peak concentrations of 3.9, 26.9, 52.3 and 55.0 ng/ml after 0, 0.5, 1 and 2 µg/kg, peaking at ~30 min.16,18

  • GH returned to baseline within 240 minutes with a half-life of about 55 minutes; the 2 µg/kg response was near-maximal.18

  • Plasma glucose, LH, FSH, TSH and IGF-1 were unaffected by hexarelin, while it caused a slight increase in prolactin, cortisol and ACTH.18

What this doesn't establish

In that acute human study IGF-1 was unaffected, and no body-composition outcomes (muscle gain, fat loss) were measured; the data are single-dose pharmacology only.

Melanotan II

Tier 1 · Human trials

Human trials report decreased appetite as a side effect of melanotan II, and animal studies suggest MC4R-mediated food-intake suppression, but the appetite effect is not its primary studied use.

Melanotan II is a lab-made copy of the natural hormone alpha-MSH, best known for tanning the skin. Because it also acts on receptors in the brain, it can reduce appetite, which is the way it relates to body composition. Its appetite effect appears to fade over time.

  • Melanotan II suppresses food intake by activating melanocortin-4 receptors on brain neurons; in obese rats the appetite suppression returned to pretreatment levels within 8–12 days.19

  • In a placebo-controlled human erectile-dysfunction study, transient decreased appetite was reported more frequently after melanotan II than placebo, though none required treatment.20

  • Community and health-authority sources describe melanotan II binding brain receptors to influence appetite and reportedly cause weight loss.21

What this doesn't establish

No human study establishes meaningful weight or fat loss from melanotan II, and the animal appetite suppression showed tolerance within roughly two weeks.

Alpha-MSH

Tier 2 · Preclinical

Human trials report that alpha-MSH improves glucose tolerance by promoting glucose uptake in skeletal muscle, with animal data showing increased glucose clearance.

Alpha-MSH is a small natural hormone the body makes from a larger precursor protein. Alongside tanning and calming inflammation, it dampens appetite and helps muscle take up sugar from the blood. These metabolic effects are how it connects to body composition.

  • Alpha-MSH acts as an agonist at the MC5R in human skeletal muscle and improves glucose tolerance in healthy humans by promoting glucose uptake in muscle cells.22

  • In animals, alpha-MSH infusion increases glucose clearance by promoting uptake in skeletal muscle, acting directly on muscle to lower circulating blood sugar.23

What this doesn't establish

The human evidence addresses glucose handling, not muscle gain or fat loss, and the studies are small early-stage physiology trials.

Ipamorelin

Tier 2 · Preclinical

Animal and laboratory studies suggest ipamorelin selectively stimulates pulsatile GH release without raising other pituitary hormones.

Ipamorelin is a synthetic five-amino-acid peptide that mimics the hunger hormone ghrelin, switching on its receptor in the pituitary to prompt a burst of growth hormone. That growth hormone, in turn, raises IGF-1, which sources link to protein building and fat breakdown. What profiles stress is its selectivity — releasing growth hormone without raising stress hormones.

  • Ipamorelin is a selective GHS-R1a agonist on anterior-pituitary somatotrophs and hypothalamic arcuate neurons, first described by Novo Nordisk in the late 1990s.25

  • In preclinical models it stimulates GH with potency comparable to GHRP-6 but without significant increases in ACTH, cortisol, prolactin, TSH, FSH or LH, and amplifies pulsatile GH rather than producing tonic elevation.25,26

  • As a ghrelin-receptor agonist within the GHS class, it was developed alongside other secretagogues to treat GH deficiency, which causes altered body composition.27

What this doesn't establish

The selectivity and GH data are preclinical; no human trial establishes muscle gain or fat loss from ipamorelin, and downstream body-composition claims are extrapolated.

MOTS-c

Tier 2 · Preclinical

Animal and laboratory studies suggest MOTS-c improves insulin sensitivity, drives fat oxidation and produces weight loss, with only one small human analog trial available.

MOTS-c is a small peptide encoded inside mitochondrial DNA — the energy factories of cells. Sources describe it as switching on AMPK, a cellular energy sensor that pushes cells to burn fuel, become more sensitive to insulin, and resist storing fat. Because exercise naturally raises it and it reproduces exercise-like effects in animals, it is often called an 'exercise-mimetic.'

  • MOTS-c is a mitochondrial-derived peptide that targets skeletal muscle, enhances glucose metabolism and activates insulin sensitivity in the skeletal muscle of diabetic mice.28

  • Acute high-intensity exercise increases MOTS-c in human skeletal muscle and plasma, and MOTS-c treatment leads to weight loss in mice alongside improved insulin sensitivity.29

  • A Phase 1a/1b study of a MOTS-c analog (20 subjects, 4 weeks) was well tolerated with reductions in liver enzymes and glucose and a trend toward weight loss; animal studies show prevention of muscle atrophy and a ~12-fold exercise-induced rise in muscle MOTS-c.30

What this doesn't establish

Human evidence is essentially absent for native MOTS-c — the single human study used a MOTS-c analog over 4 weeks in 20 subjects — so fat loss and body-composition benefit in people remain unproven.

AOD-9604

Tier 2 · Preclinical

Animal and laboratory studies suggest AOD-9604 induces weight loss and increases fat oxidation, with lower-tier commentary citing human trials.

AOD-9604 is a small synthetic peptide copied from the tail end of human growth hormone — the part thought to drive its fat-burning activity, separate from its growth and blood-sugar effects. It was designed to encourage fat breakdown and reduce new fat formation without raising blood sugar or IGF-1. In animal studies it reduced body weight and body fat.

  • AOD-9604 induced weight loss and increased lipolytic sensitivity after long-term treatment in obese mice, and restored repressed β3-AR RNA to levels comparable with lean mice.31,32

  • In β3-AR knockout mice, long-term treatment failed to reproduce the weight and lipolysis changes seen in wild-type mice, yet acutely still increased energy expenditure and fat oxidation — indicating the lipolytic action is not directly mediated through β3-AR.31,32

  • AOD-9604 is a 16-amino-acid fragment corresponding to the C-terminal lipolytic domain of hGH (roughly residues 177–191) that stimulates lipolysis and inhibits lipogenesis without activating the hGH receptor, raising IGF-1 or impairing glucose metabolism.33

What this doesn't establish

The controlled mechanistic evidence is in mice; sources noting human trials and clean safety are low-tier, and no high-quality human data establish fat loss for this goal.

How they work together

Check this stack

Several of these compounds converge on the same growth-hormone axis and are therefore redundant rather than additive when combined. Sermorelin, CJC-1295 and tesamorelin all act on the same GHRH receptor, so stacking any two mostly doubles one mechanism; tesamorelin is the visceral-fat specialist within that group. Likewise ipamorelin, hexarelin and MK-677 all hit the ghrelin receptor (GHS-R1a), so combining them competes for one receptor — and MK-677's long, sustained occupancy plus appetite and fluid-retention effects can blunt a short-acting injectable and work against a fat-loss goal. The genuinely complementary pairings cross mechanisms: a GHRH-side agent plus a ghrelin-side agent (for example sermorelin or CJC-1295 with ipamorelin) can produce a larger, still-pulsatile GH pulse, and this GHRH+GHRP pairing is the classic synergistic GH strategy. Follistatin builds muscle by blocking myostatin, an entirely separate pathway from the GH agents, so it is reported as complementary to sermorelin, CJC-1295, hexarelin, tesamorelin and MK-677 for body composition. AOD-9604 mobilizes fat directly at the adipocyte and MOTS-c enhances fat oxidation, so the two are logically complementary, as is AOD-9604 with the GH-raising agents; and MOTS-c and follistatin may converge on the same myostatin signal, though weakly characterized. Melanotan II and alpha-MSH act on the same melanocortin receptors, making them redundant with each other. Combining agents that raise IGF-1 through different receptors (for example MK-677 with CJC-1295 or tesamorelin) can push IGF-1 higher than intended and warrants caution.

  • Follistatin-344 + MOTS-c

    Worth caution — see why below

    MOTS-c is reported to regulate myostatin through a CK2-PTEN-mTORC2-AKT-FOXO1 axis, converging on the same muscle-limiting signal that Follistatin neutralizes directly. Both also add metabolic/anti-inflammatory benefits, so they may reinforce each other on body composition, though this convergence is only weakly characterized.

    Not fully established

    The proposed relationship claims both peptides converge on myostatin regulation as a shared downstream mechanism. However, the mechanism descriptions show fundamentally different modes of action: Follistatin directly targets and sequesters myostatin/GDF-8 as a ligand trap, while MOTS-c's connection to myostatin is indirect and occurs through a complex CK2-PTEN-mTORC2-AKT-FOXO1 axis. The MOTS-c description itself notes this pathway 'regulates myostatin' but does not establish that this is a primary or well-characterized mechanism—it appears as one element among many (NRF2, AMPK, GLUT4, STAT3, IL-10). Additionally, while both peptides have 'anti_inflammatory' tags, the mechanisms underlying this effect differ substantially: Follistatin works through TGF-beta superfamily antagonism and SMAD2/3 inhibition, while MOTS-c works through Keap1-Nrf2 antioxidant pathways and AMPK activation. The claim of 'same_downstream' convergence on myostatin is not clearly supported by the provided mechanisms, which show distinct upstream pathways with only speculative indirect overlap on myostatin regulation.

  • Follistatin-344 + CJC-1295

    Worth caution — see why below

    Follistatin-344 builds muscle by blocking myostatin/activin (disinhibiting mTOR/Akt), an entirely different mechanism from CJC-1295's GH/IGF-1 elevation. Both converge on protein synthesis and lean mass, so they can be complementary for body-composition goals via independent pathways.

    Not fully established

    Both peptides' mechanisms clearly support the claimed complementary relationship and shared dimensions. CJC-1295 increases plasma GH and IGF-I through GHRH-R signaling and cAMP-PKA pathways, with IGF-1_signaling and protein_synthesis explicitly tagged. Follistatin-344 blocks myostatin/activin, disinhibiting mTOR/Akt and IGF-1R signaling, also with IGF1_signaling and protein_synthesis tagged. The mechanisms are mechanistically distinct (GH axis elevation vs. TGF-beta antagonism) yet both converge on protein synthesis and lean mass via independent pathways—the definition of complementarity. The explanation accurately reflects the provided mechanism material without contradiction.

  • Ipamorelin + Hexarelin

    Worth caution — see why below

    Both hexarelin and ipamorelin are growth hormone secretagogues that switch on the exact same pituitary receptor (GHS-R1a) to trigger a GH pulse, so stacking them is largely redundant rather than additive — you're pushing the same button twice. The key difference is selectivity: hexarelin also raises ACTH, cortisol and prolactin and blunts (desensitizes) with continued use, whereas ipamorelin gives a cleaner GH pulse without those extra hormones. For most goals you'd choose one, and ipamorelin is the cleaner GHS-R1a option.

    Not fully established

    Both peptides' mechanisms clearly establish they target the same receptor (GHS-R1a/GHSR-1a) and activate the same primary pathway (phospholipase C → IP3/intracellular calcium → GH exocytosis) to achieve pulsatile GH release and IGF-1 elevation. The shared dimension 'GH_axis' is explicitly documented in both mechanisms. The explanation accurately reflects the mechanism material: hexarelin's additional effects on ACTH/cortisol/prolactin are documented in its mechanism, while ipamorelin's mechanism explicitly states 'Selective GH secretion without ACTH/cortisol/prolactin release.' The characterization of functional redundancy on the primary GH-axis mechanism is justified by the identical receptor targeting and overlapping downstream signaling pathways described.

  • Ipamorelin + MK-677

    Worth caution — see why below

    MK-677 (ibutamoren) is an oral non-peptide that hits the same ghrelin receptor (GHS-R1a) as ipamorelin. Running both means competing for the identical receptor and GH-release pathway, so the effect is redundant rather than additive. MK-677 also produces a long, sustained receptor activation plus notable appetite stimulation and water retention — layering ipamorelin on top adds little extra GH while compounding those side effects. Most people should use one GHS-R1a agonist, not two.

    Not fully established

    Both peptides' mechanisms clearly establish they target the same receptor (GHS-R1a/GHSR-1a ghrelin receptor) and activate overlapping downstream pathways (Gq/11-coupled phospholipase C → IP3/intracellular calcium → GH-vesicle exocytosis). Both produce pulsatile GH secretion and IGF-1 elevation through the GH/IGF-1 axis. The shared dimensions (GH_axis, IGF1_signaling) are explicitly supported by both descriptions. The mechanism material confirms both are ghrelin receptor agonists operating through the same receptor and GH-release pathway, justifying the 'same_mechanism' classification and the claim of redundancy rather than additivity.

  • Melanotan II + Alpha-MSH

    Worth caution — see why below

    Melanotan II is a synthetic cyclic copy of alpha-MSH that activates the same melanocortin receptors (MC1R/MC3R/MC4R/MC5R) through the identical cAMP pathway, producing the same tanning and appetite-suppressing effects. Combining the two is redundant and simply compounds melanocortin overactivation (nausea, flushing, blood-pressure and libido effects) — choose one, don't layer them.

    Not fully established

    Both peptides share identical melanocortin receptor targets (MC1R, MC3R, MC4R, MC5R) and activate the same cAMP-PKA signaling pathway. Both produce appetite suppression/anorexigenic effects and skin pigmentation through this shared mechanism. The mechanism descriptions explicitly confirm Melanotan II is a synthetic analog of alpha-MSH that activates the same receptors via the same cAMP cascade. The claimed shared dimensions (cAMP_PKA and appetite_regulation) are directly supported by both peptides' approved tags and pathway descriptions. The explanation that combining them would be redundant and compound melanocortin overactivation is mechanistically justified by their identical receptor and pathway profiles.

  • Sermorelin + Tesamorelin

    Worth caution — see why below

    Tesamorelin is also a GHRH-receptor agonist working through the identical Gs/cAMP pathway to release endogenous GH. Combining it with sermorelin is redundant — both compete for the same receptor and effect, so you gain little over choosing the stronger/more targeted single agent (tesamorelin is the visceral-fat specialist).

    Not fully established

    Both peptides' mechanisms clearly establish they are GHRH receptor agonists (Sermorelin targets GHRH receptor on somatotrophs; Tesamorelin targets GHRHR class B GPCR). Both activate identical signaling pathways: Gs/adenylyl cyclase/cAMP leading to pulsatile GH release from anterior pituitary somatotrophs. Both share all four claimed dimensions in their approved tags: GH_axis, lipolysis, IGF1_signaling, and cAMP_PKA. The mechanism descriptions explicitly confirm both work through the same receptor and same second-messenger cascade to achieve endogenous GH stimulation. The explanation's characterization of functional redundancy at the receptor level is directly supported by the provided mechanisms.

  • Sermorelin + CJC-1295

    Worth caution — see why below

    Both are GHRH analogs that hit the exact same receptor (GHRH-R) on pituitary somatotrophs to trigger the cAMP-driven GH pulse. Stacking them is redundant rather than additive — you'd just be doubling up on one mechanism. CJC-1295 is longer-acting than sermorelin, so most people choose one or the other rather than combining.

    Not fully established

    Both peptides' mechanisms clearly establish they are GHRH analogs targeting the same GHRH receptor on anterior pituitary somatotrophs. Both activate the cAMP/PKA pathway (Gs/adenylyl cyclase/cAMP) to stimulate GH secretion and downstream IGF-1 signaling. The shared dimensions (GH_axis, protein_synthesis, IGF1_signaling, cAMP_PKA) are explicitly documented in both mechanisms. The key mechanistic difference is pharmacokinetics (CJC-1295's albumin-binding confers longer half-life via DAC modification), not the fundamental signaling pathway or receptor target. The explanation that stacking would be redundant rather than additive is mechanistically sound given they engage identical downstream cascades through the same receptor. This qualifies as 'same_mechanism' with different duration profiles.

  • AOD-9604 + MK-677

    Worth caution — see why below

    MK-677 raises GH/IGF-1 (which can support lipolysis) but also markedly stimulates appetite and can promote fluid retention, potentially working against AOD-9604's fat-loss goal. Worth understanding the appetite trade-off before combining.

  • Hexarelin + MK-677

    Worth caution — see why below

    MK-677 is an oral ghrelin-mimetic that hits the same GHS-R1a receptor hexarelin does. Combining them is redundant — both compete for and desensitize the same receptor — and MK-677's long half-life keeps that receptor occupied around the clock, which can blunt the pulse a short-acting injectable like hexarelin is trying to create. Pick one GHS-R1a agonist rather than layering two.

    Not fully established

    Both peptides' mechanisms clearly establish GHS-R1a as their primary shared target. Hexarelin's mechanism explicitly states it 'binds to the growth hormone secretagogue receptor (GHS-R1a)' and MK-677's mechanism confirms it 'switches on the ghrelin receptor (GHS-R1a)'. Both activate the same Gq/11-coupled phospholipase C / IP3 / intracellular calcium cascade leading to GH-vesicle exocytosis. Both share the GH_axis and IGF1_signaling approved tags and produce overlapping effects (pulsatile GH secretion, elevated IGF-1). The proposed explanation about receptor desensitization and the contrast between pulsatile (hexarelin) vs. continuous (MK-677) receptor occupancy is mechanistically sound given their described pharmacokinetic profiles and the shared GHS-R1a pathway. The claimed shared dimensions (GH_axis, IGF1_signaling) are directly supported by both mechanisms.

  • Hexarelin + CJC-1295

    Worth caution — see why below

    Hexarelin is a ghrelin-receptor (GHS-R1a) agonist, a different upstream mechanism from CJC-1295's GHRH receptor. The two converge on greater GH secretion, so combining amplitude (GHRH) with a secretagogue can be additive. Note hexarelin also stimulates ACTH/cortisol and prolactin and can desensitize its receptor over time, so it's less selective than ipamorelin.

    Not fully established

    Both peptides' mechanisms clearly target the GH_axis and IGF1_signaling dimensions through distinct upstream pathways: CJC-1295 acts via GHRH-R (cAMP-dependent cascade), while Hexarelin acts via GHS-R1a (PLC/IP3/PKC cascade). The mechanisms explicitly show both increase plasma GH and IGF-1 levels through different receptor signaling routes, which justifies the 'complementary' relationship claim of convergent but mechanistically distinct GH stimulation. The explanation accurately reflects the provided mechanism material—different receptors, shared downstream GH/IGF-1 axis effects, and potential additive amplification of GH secretion.

  • Tesamorelin + MK-677

    Worth caution — see why below

    Tesamorelin is a stabilized GHRH analog that raises GH/IGF-1 through the GHRH receptor, distinct from MK-677's ghrelin-receptor pathway. Both feed the same GH/IGF-1 axis, so they can be additive on GH output. Note a practical tension: tesamorelin is used specifically to reduce visceral fat, whereas MK-677 raises appetite and can promote fluid retention and insulin resistance, which may partly counter the body-composition goal.

    Not fully established

    Both peptides' mechanisms clearly converge on the GH/IGF-1 axis as a shared downstream endpoint, despite distinct upstream targets (GHS-R1a vs GHRHR). MK-677 mechanisms show 'GH-vesicle exocytosis in pituitary somatotrophs' and 'GH/IGF-1 axis (IGF-1, IGFBP-3 elevation)' with approved tags including GH_axis and IGF1_signaling. Tesamorelin mechanisms show 'GH release from anterior pituitary somatotrophs' and 'Hepatic JAK2/STAT5 induction of IGF-1' with matching approved tags GH_axis and IGF1_signaling. Both mechanisms explicitly document IGF-1 elevation. Regarding lipolysis: Tesamorelin's mechanisms explicitly list 'Lipolysis' and 'Reduction of visceral adipose tissue' as effects. MK-677's mechanisms do not explicitly mention lipolysis as a direct effect—it lists 'Increased fat-free/lean mass' and 'Reversal of diet-induced protein catabolism,' which are anabolic rather than lipolytic. The claim of shared lipolysis dimension is therefore only partially supported by the provided mechanisms (supported for tesamorelin, not documented for MK-677). However, the core same_downstream relationship on GH_axis and IGF1_signaling is clearly justified by both mechanisms converging on pituitary GH release and subsequent IGF-1 elevation through distinct receptor pathways.

  • Tesamorelin + CJC-1295

    Worth caution — see why below

    Tesamorelin is also a stabilized GHRH analog acting on the same GHRH-R/cAMP pathway to raise GH and IGF-1. Combining it with CJC-1295 stacks two drugs doing the identical job, which is redundant and could over-drive IGF-1 without adding a distinct benefit. Choose one GHRH agent for a given goal.

    Not fully established

    Both peptides' mechanisms clearly establish they target the same GHRH receptor (GHRH-R/GHRHR) on anterior-pituitary somatotrophs and activate the identical cAMP-dependent signaling cascade (Gs-alpha/adenylate cyclase/cAMP/PKA pathway). Both produce dose-dependent increases in GH secretion and IGF-1 levels through the same endocrine axis. The shared mechanism tags (GH_axis, IGF1_signaling, cAMP_PKA) are explicitly supported by both descriptions. The proposed relationship correctly identifies that both are GHRH analogs operating through the same receptor and pathway, making them mechanistically redundant rather than complementary. The explanation's logic about stacking two agents with identical mechanisms is justified by the provided mechanism material.

  • MK-677 + CJC-1295

    Worth caution — see why below

    MK-677 is an oral ghrelin-receptor agonist that raises GH/IGF-1 via a different receptor than CJC-1295. The mechanisms are complementary (pulse amplitude from GHRH vs. secretagogue-driven pulses), but because MK-677 produces sustained IGF-1 elevation, combining the two can push IGF-1 high — monitor levels and watch for water retention/appetite effects.

    Not fully established

    The mechanisms clearly establish complementary action on the GH axis through distinct receptors: CJC-1295 targets GHRH-R (direct GHRH pathway via cAMP-PKA cascade), while MK-677 targets GHS-R1a (ghrelin-mimetic pathway via Gq/11-PLC-IP3-calcium cascade). Both peptides share three approved tags (GH_axis, protein_synthesis, IGF1_signaling) and both increase pulsatile GH secretion and IGF-1 elevation, but through different mechanisms. The explanation correctly identifies the complementary nature: CJC-1295 amplifies endogenous pulsatile GH with preserved pulse pattern via GHRH-R, while MK-677 drives GH-vesicle exocytosis and modulates hypothalamic GHRH/somatostatin via GHS-R1a. The proposed shared dimensions are explicitly supported by the approved tags and mechanism descriptions for both peptides. The caveat about combined IGF-1 elevation and monitoring is a reasonable inference from the stated effects (2-10 fold GH increase for CJC-1295, sustained IGF-1 elevation for MK-677) but does not contradict the complementary relationship claim.

  • Follistatin-344 + Sermorelin

    May be complementary

    Sermorelin boosts the body's own GH/IGF-1 output to support lean mass, whereas Follistatin drives hypertrophy by neutralizing myostatin. Different upstream mechanisms converge on the same goal of building muscle, so they complement rather than duplicate each other.

    Not fully established

    Both peptides' mechanisms clearly support the proposed complementary relationship. Follistatin-344 directly targets myostatin/activin signaling to disinhibit muscle growth and explicitly lists IGF-1R signaling and protein_synthesis as approved tags. Sermorelin stimulates endogenous GH release, which increases IGF-1 and protein_synthesis (both approved tags). The mechanisms describe distinct upstream pathways (ligand sequestration via Follistatin vs. GHRH receptor activation via Sermorelin) that converge on shared downstream dimensions (IGF1_signaling and protein_synthesis). Both improve body composition and lean mass through different routes, which is the hallmark of complementary action. The explanation accurately reflects the mechanistic material provided.

  • Follistatin-344 + Hexarelin

    May be complementary

    Hexarelin raises IGF-1 and, notably, suppresses TGF-beta driven fibrosis — overlapping with Follistatin's own anti-fibrotic, muscle-sparing action. One works through GH/IGF-1, the other through myostatin/activin blockade, so they converge on healthier, larger muscle through different routes.

    Not fully established

    Both peptides' mechanisms clearly support the three claimed shared dimensions. (1) IGF1_signaling: Follistatin explicitly lists 'IGF-1R signaling (partial mediator of hypertrophy)' and Hexarelin 'Increases IGF-1 with prolonged administration' — both documented. (2) mTOR_PI3K: Follistatin shows 'mTOR pathway (disinhibited)' and 'Akt phosphorylation (increased)'; Hexarelin shows 'PI3K/Akt' pathway activation — both present. (3) anti_inflammatory: Follistatin lists 'anti_inflammatory' tag and 'Reduced muscle fibrosis and inflammatory infiltration'; Hexarelin lists 'anti_inflammatory' tag and 'NLRP3 inflammasome / IL-18 / NF-κB suppression' plus 'TGF-β suppression (anti-fibrotic)'. The explanation correctly identifies that they converge on muscle health via different primary mechanisms (GH/IGF-1 axis vs. myostatin/activin blockade), with overlapping downstream effects on fibrosis reduction and anti-inflammatory signaling. The complementary relationship is justified by mechanistic convergence on shared pathways despite distinct primary targets.

  • Follistatin-344 + Tesamorelin

    May be complementary

    Tesamorelin raises GH/IGF-1 and preferentially strips visceral fat, while Follistatin adds muscle mass and reduces adiposity by blocking myostatin. Their combined effect leans toward improved body composition (more lean mass, less fat) through distinct pathways.

    Not fully established

    Both peptides' mechanisms establish IGF1_signaling as a shared dimension: Follistatin explicitly lists IGF-1R signaling as a partial mediator of hypertrophy (approved tag: IGF1_signaling), and Tesamorelin's mechanism directly increases endogenous IGF-1 via GH release and hepatic JAK2/STAT5 induction (approved tag: IGF1_signaling). The proposed complementary relationship is justified—they operate through distinct primary mechanisms (ligand sequestration vs. GHRH receptor activation) but converge on IGF-1 signaling to promote anabolic effects. The explanation accurately reflects that Follistatin drives muscle hypertrophy and reduces adiposity through TGF-beta antagonism while Tesamorelin increases GH/IGF-1 and preferentially targets visceral fat through cAMP/GH axis activation, making them mechanistically complementary for body composition improvement.

  • Follistatin-344 + MK-677

    May be complementary

    MK-677 elevates GH/IGF-1 and improves nitrogen balance, supporting protein synthesis from the anabolic-hormone side, while Follistatin releases the myostatin brake. The two attack muscle growth from separate angles, making them additive rather than redundant.

    Not fully established

    Both peptides' mechanisms clearly establish the claimed shared dimensions. Follistatin explicitly targets IGF-1R signaling as a 'partial mediator of hypertrophy' and is tagged with IGF1_signaling and protein_synthesis. MK-677 directly elevates IGF-1 levels and IGFBP-3, with approved tags for both IGF1_signaling and protein_synthesis, plus reversal of protein catabolism via improved nitrogen balance. The proposed complementary relationship is justified: Follistatin removes inhibitory signals (myostatin/activin blockade, SMAD2/3 inhibition, mTOR disinhibition), while MK-677 provides positive anabolic drive via the GH/IGF-1 axis. These represent mechanistically distinct pathways (ligand sequestration + receptor antagonism vs. GHS-R1a agonism → GH secretion) converging on the same downstream effectors (IGF-1 signaling, protein synthesis, mTOR activation). The mechanisms support the claim that they are additive rather than redundant.

  • Ipamorelin + Sermorelin

    May be complementary

    Sermorelin is a GHRH-receptor agonist, a different upstream pathway from ipamorelin's ghrelin receptor, but both feed into the same GH/IGF-1 axis. Pairing a GHRH analog with a ghrelin-receptor agonist is the well-known two-pronged strategy: sermorelin drives GHRH-side signaling while ipamorelin adds the ghrelin-side push and blunts somatostatin, giving a bigger combined GH pulse while keeping the release pulsatile.

    Not fully established

    The mechanism descriptions clearly establish that both peptides converge on the GH/IGF-1 axis despite different upstream targets. Ipamorelin targets GHSR-1a (ghrelin receptor) and sermorelin targets GHRH receptor—distinct receptors. However, both pathways lead to pulsatile GH release and IGF-1 elevation. The shared dimensions are well-justified: (1) GH_axis—both explicitly stimulate GH secretion via different receptor pathways; (2) IGF1_signaling—both increase IGF-1 as a downstream effect of elevated GH; (3) cAMP_PKA—ipamorelin's mechanism includes 'cAMP / protein kinase A (PKA)' and sermorelin's explicitly uses 'Gs/adenylyl cyclase/cAMP' and is tagged with 'cAMP_PKA'. The explanation correctly identifies them as complementary upstream inputs (ghrelin-side vs. GHRH-side) that converge on common downstream GH secretion and IGF-1 signaling. This is a classic example of same_downstream relationship where different receptor agonists feed into the same physiological axis.

  • Ipamorelin + AOD-9604

    May be complementary

    AOD-9604 drives fat mobilization through a GH-independent route (beta-3 adrenergic/HSL activation, not the GH receptor), while ipamorelin promotes lipolysis indirectly via GH release. Because they hit fat metabolism from different directions and both ultimately raise cAMP-driven hormone-sensitive lipase activity, they can be used together for fat-loss goals without receptor competition.

    Not fully established

    Both peptides' mechanisms clearly establish the claimed shared dimensions and complementary relationship. (1) Lipolysis: Ipamorelin effects include 'Lipolysis (reported)' via 'Hormone-sensitive lipase / lipolysis' pathway; AOD-9604 effects include 'Stimulation of lipolysis (fat mobilization)' via 'Hormone-sensitive lipase activation, Lipolysis stimulation' pathway. (2) cAMP_PKA: Ipamorelin pathways include 'cAMP / protein kinase A (PKA)'; AOD-9604 pathways include 'Cyclic AMP (cAMP) elevation' and approved tag 'cAMP_PKA'. (3) Complementarity via different routes: The mechanisms confirm distinct pathways—ipamorelin acts through GHSR-1a → GH release → IGF-1 signaling → lipolysis, while AOD-9604 acts through beta-3 adrenergic receptor upregulation → cAMP elevation → HSL activation, explicitly stated as 'effect not directly receptor-mediated' and 'Does NOT meaningfully bind the classical hGH receptor.' The explanation's claim of 'GH-independent route' for AOD-9604 and indirect GH-mediated lipolysis for ipamorelin is directly supported by the provided mechanisms. No receptor competition is evident from the descriptions.

  • Ipamorelin + Tesamorelin

    May be complementary

    Tesamorelin is a stabilized GHRH analog acting on the GHRH receptor — a distinct mechanism from ipamorelin's ghrelin receptor — but both raise GH/IGF-1 and support fat loss. Combining a GHRH-side driver with ipamorelin's ghrelin-side amplification produces a larger GH pulse, and tesamorelin's specific strength in reducing visceral fat can complement ipamorelin's reported lipolysis for body-composition goals.

    Not fully established

    The mechanism descriptions clearly establish that both peptides converge on shared downstream pathways despite distinct receptor targets. Ipamorelin acts via GHSR-1a (ghrelin receptor) while tesamorelin acts via GHRHR (GHRH receptor)—these are indeed different upstream mechanisms. However, both demonstrably activate the GH_axis (pulsatile GH release from anterior pituitary somatotrophs), both elevate IGF-1 (ipamorelin via GH→IGF-1 signaling; tesamorelin via hepatic JAK2/STAT5 induction), both engage cAMP_PKA signaling (ipamorelin explicitly lists cAMP/PKA; tesamorelin's Gs-alpha/adenylate cyclase/cAMP pathway activates PKA), and both produce lipolysis effects. The shared_downstream relationship type is justified: the peptides use different receptors but converge on common effector pathways and biological outcomes. The four claimed shared dimensions (GH_axis, IGF1_signaling, cAMP_PKA, lipolysis) are all explicitly supported in the mechanism material for both peptides. The explanation accurately describes the complementary nature of their distinct mechanisms feeding into overlapping downstream biology.

  • Ipamorelin + CJC-1295

    May be complementary

    Ipamorelin works through a different receptor (the ghrelin/GHS-R1a receptor) than CJC-1295's GHRH-R. GHRH analogs increase the size of each GH pulse while ghrelin-mimetics increase pulse frequency and suppress somatostatin — so the two amplify each other's GH release. This GHRH + GHRP pairing is the classic synergistic GH stack.

    Not fully established

    The mechanisms clearly establish complementary action on the GH_axis and IGF1_signaling. CJC-1295 targets GHRH-R and amplifies endogenous pulsatile GH secretion via cAMP-PKA pathways, increasing GH pulse amplitude. Ipamorelin targets GHSR-1a (ghrelin receptor) and triggers pulsatile GH release via Gαq/11-PLC and cAMP-PKA pathways. The proposed explanation that GHRH analogs increase pulse size while ghrelin-mimetics increase pulse frequency is mechanistically consistent with their distinct receptor targets and signaling cascades. Both converge on GH secretion and downstream IGF-1 signaling but through different physiological mechanisms (GHRH stimulation vs. ghrelin mimicry), making them complementary rather than redundant. The shared dimensions (GH_axis, IGF1_signaling) are explicitly supported by both peptides' documented effects and approved tags.

  • Sermorelin + AOD-9604

    May be complementary

    Sermorelin drives fat loss indirectly by prompting the pituitary to release more of the body's own growth hormone, whereas AOD-9604 acts directly on fat cells to trigger lipolysis. Different upstream triggers converging on the same fat-burning outcome make them potentially additive rather than redundant.

    Not fully established

    Both peptides' mechanisms establish the claimed shared dimensions and support a complementary relationship. (1) Lipolysis: AOD-9604 directly stimulates lipolysis via beta3-AR and cAMP/PKA pathways; Sermorelin indirectly promotes lipolysis through GH/IGF-1 signaling, which is known to enhance fat mobilization. Both mechanisms converge on fat-burning outcomes. (2) cAMP_PKA: AOD-9604 explicitly activates cAMP/PKA; Sermorelin activates Gs/adenylyl cyclase/cAMP, also engaging cAMP_PKA signaling. The explanation correctly identifies that they use different upstream triggers (direct beta3-AR stimulation vs. GHRH receptor-mediated GH axis activation) converging on shared downstream pathways and lipolysis. This represents genuine complementarity—different mechanisms, same endpoint, potentially additive effects—rather than redundancy or antagonism. The mechanism descriptions support this characterization.

  • Sermorelin + Hexarelin

    May be complementary

    Sermorelin is a GHRH-receptor agonist and hexarelin is a GHS-R1a agonist — two different receptors that feed the same GH secretory pathway. Pairing a GHRH analog with a ghrelin-mimetic secretagogue is a well-established synergistic strategy: the GHRH signal and the secretagogue signal reinforce each other for a bigger pulse than either produces alone.

    Not fully established

    Both peptides' mechanisms clearly converge on the GH/IGF-1 axis despite using different receptors. Hexarelin targets GHS-R1a and Sermorelin targets GHRH receptor—distinct receptors as stated. Both mechanisms explicitly result in stimulation of pulsatile GH release and increased IGF-1, confirming the shared downstream dimensions (GH_axis, IGF1_signaling). The explanation correctly identifies that these are two different receptor pathways (Hexarelin: GHS-R1a → PLC/IP3/Ca²⁺/PKC; Sermorelin: GHRH receptor → Gs/cAMP/MAPK) that converge on the same physiological outcome (GH secretion and IGF-1 elevation). The proposed synergistic mechanism—that two different upstream signals reinforce each other at the level of GH secretion—is consistent with both mechanisms describing independent pathways to the same endpoint. This is a classic example of same_downstream relationship.

  • Sermorelin + MK-677

    May be complementary

    Sermorelin is a GHRH-receptor agonist, a different upstream trigger from MK-677's ghrelin-receptor action, yet both raise pulsatile GH and IGF-1 and both are reported to deepen slow-wave sleep. Using a GHRH signal plus a ghrelin-mimetic can enhance the GH pulse more than either alone, and their overlapping sleep benefits reinforce each other.

    Not fully established

    Both peptides' mechanisms clearly converge on the same downstream GH/IGF-1 axis despite different upstream triggers. MK-677 activates GHS-R1a (ghrelin receptor) via Gq/11-phospholipase C cascade; Sermorelin activates GHRH receptor via Gs/adenylyl cyclase/cAMP. Both mechanisms result in pulsatile GH secretion from pituitary somatotrophs and subsequent IGF-1 elevation. Both approved tags explicitly include GH_axis, IGF1_signaling, protein_synthesis, and sleep_architecture. The mechanism descriptions confirm both increase pulsatile GH release, elevate IGF-1, improve body composition through protein synthesis/lean mass gains, and increase slow-wave/deep sleep. The proposed explanation that they use different upstream pathways (ghrelin vs GHRH) but converge on common downstream GH release and sleep effects is directly supported by the provided mechanisms. This is a classic example of convergent pathway activation producing overlapping phenotypes.

  • AOD-9604 + Tesamorelin

    May be complementary

    Both push fat loss but by different routes: tesamorelin raises endogenous growth hormone via the GHRH receptor, while AOD-9604 stimulates fat breakdown directly in fat cells (cAMP rise, hormone-sensitive lipase) without acting on the GH receptor. Because their entry points differ, they can reinforce each other on the same goal of reducing (especially visceral) fat.

    Not fully established

    The mechanisms clearly establish complementary action on the two shared dimensions. Both peptides elevate cAMP and promote lipolysis, but through distinct pathways: Tesamorelin acts via GHRHR → GH release → IGF-1 signaling → lipolysis, while AOD-9604 acts via beta3-AR → direct cAMP elevation → hormone-sensitive lipase activation → lipolysis. The mechanism descriptions explicitly confirm AOD-9604 does NOT meaningfully bind the classical hGH receptor, and Tesamorelin's effects are GH-axis dependent, confirming their entry points are genuinely different. Both converge on cAMP_PKA and lipolysis as endpoints, making them mechanistically complementary rather than redundant. The explanation accurately reflects the provided mechanisms.

  • AOD-9604 + MOTS-c

    May be complementary

    MOTS-c improves fat metabolism and drives fat oxidation/adipose browning via AMPK and mitochondrial signaling, while AOD-9604 mobilizes fat by raising cAMP and activating hormone-sensitive lipase. Mobilization (AOD) plus enhanced oxidation (MOTS-c) are logically complementary steps of the same fat-loss process.

    Not fully established

    Both peptides' mechanisms clearly support lipolysis-related effects through distinct but complementary pathways. AOD-9604 is explicitly tagged with 'lipolysis' and activates hormone-sensitive lipase via cAMP-PKA signaling to mobilize fat. MOTS-c is also tagged with 'lipolysis' and promotes fat oxidation/browning via AMPK activation and mitochondrial signaling. The proposed explanation accurately reflects the mechanism material: AOD-9604 mobilizes stored fat (lipolysis step), while MOTS-c enhances oxidation of mobilized fat (utilization step). These represent sequential, non-redundant contributions to fat loss that logically complement each other. The shared dimension (lipolysis) is explicitly supported by both peptides' approved tags and their distinct mechanistic contributions to fat metabolism are well-documented in the provided material.

  • AOD-9604 + CJC-1295

    May be complementary

    CJC-1295 boosts GH (and downstream IGF-1) through the GHRH receptor, a hormone-mediated path to fat mobilization, while AOD-9604 stimulates lipolysis directly at the adipocyte. The two hit fat loss from different directions and are not redundant with each other.

    Not fully established

    Both peptides' mechanisms explicitly activate cAMP-PKA signaling: AOD-9604 via beta3-AR stimulation leading to cAMP elevation and hormone-sensitive lipase activation; CJC-1295 via GHRH-R engagement triggering the cAMP-dependent GH secretory cascade. The proposed relationship correctly identifies that they operate through distinct primary targets (beta3-AR vs GHRH-R) and distinct tissue sites of action (direct adipocyte lipolysis vs pituitary GH axis), making them mechanistically complementary rather than redundant. Both converge on cAMP-PKA as a shared downstream pathway dimension, and the explanation accurately reflects this non-overlapping yet synergistic mechanism architecture described in the provided material.

  • Hexarelin + Tesamorelin

    May be complementary

    Tesamorelin is a stabilized GHRH analog; hexarelin is a GHS-R1a secretagogue. They act on distinct receptors that both drive pituitary GH release, so combined they can produce a larger, more physiologic GH/IGF-1 response — with tesamorelin adding a documented visceral-fat-lowering effect. Monitor IGF-1 since two upstream drivers stacking can push it higher than intended.

    Not fully established

    Both peptides' mechanisms clearly converge on the GH/IGF-1 axis despite distinct receptor targets. Hexarelin targets GHS-R1a and stimulates pulsatile GH release and increases IGF-1 with prolonged administration. Tesamorelin targets GHRHR and increases endogenous GH (pulsatile release) with dose-dependent IGF-1 increase. The mechanisms establish they act on different upstream receptors (GHS-R1a vs GHRHR) but both drive the same downstream GH secretion and IGF-1 signaling pathway. Lipolysis is explicitly documented for tesamorelin (visceral adipose tissue reduction, hepatic fat reduction). While hexarelin's mechanism material does not explicitly list lipolysis as an effect, the shared GH_axis and IGF1_signaling dimensions are clearly supported. The proposed relationship correctly identifies that these are distinct upstream drivers converging on common downstream GH/IGF-1 signaling, making 'same_downstream' an accurate characterization. The explanation's concern about stacking effects on IGF-1 is mechanistically sound given both peptides independently increase IGF-1 through the same axis.

  • Tesamorelin + MOTS-c

    No known conflict in the research

    Both reduce adiposity, especially visceral and hepatic fat, but through unrelated mechanisms: tesamorelin raises GH/IGF-1 to drive lipolysis, while MOTS-c acts through AMPK-driven metabolism and adipose browning. These non-overlapping fat-loss pathways can complement each other for body-composition goals.

    Not fully established

    Both peptides' mechanisms clearly support lipolysis as a shared dimension with complementary (non-overlapping) pathways. MOTS-c mechanisms include AMPK activation, white adipose tissue browning/thermogenesis, and reduced fat mass via metabolic reprogramming. Tesamorelin mechanisms include GH/IGF-1 axis activation driving lipolysis and visceral fat reduction via Gs-alpha/cAMP/PKA signaling. The proposed explanation accurately reflects these distinct mechanistic routes to fat loss, and both peptides are tagged with 'lipolysis,' confirming this shared dimension. The claim that these pathways are unrelated and complementary is well-supported by the non-overlapping receptor targets (NFE2L2/Keap1/AMPK for MOTS-c vs. GHRHR/GH/IGF-1 for tesamorelin) and distinct downstream signaling cascades described in the mechanisms.

  • Follistatin-344 + Ipamorelin

    No documented interaction in our data — that is not a safety clearance.

  • Follistatin-344 + Melanotan II

    No documented interaction in our data — that is not a safety clearance.

  • Follistatin-344 + AOD-9604

    No documented interaction in our data — that is not a safety clearance.

  • Follistatin-344 + Alpha-MSH

    No documented interaction in our data — that is not a safety clearance.

  • Ipamorelin + Melanotan II

    No documented interaction in our data — that is not a safety clearance.

  • Ipamorelin + Alpha-MSH

    No documented interaction in our data — that is not a safety clearance.

  • Ipamorelin + MOTS-c

    No documented interaction in our data — that is not a safety clearance.

  • Melanotan II + Sermorelin

    No documented interaction in our data — that is not a safety clearance.

  • Melanotan II + AOD-9604

    No documented interaction in our data — that is not a safety clearance.

  • Melanotan II + Hexarelin

    No documented interaction in our data — that is not a safety clearance.

  • Melanotan II + Tesamorelin

    No documented interaction in our data — that is not a safety clearance.

  • Melanotan II + MK-677

    No documented interaction in our data — that is not a safety clearance.

  • Melanotan II + MOTS-c

    No documented interaction in our data — that is not a safety clearance.

  • Melanotan II + CJC-1295

    No documented interaction in our data — that is not a safety clearance.

  • Sermorelin + Alpha-MSH

    No documented interaction in our data — that is not a safety clearance.

  • Sermorelin + MOTS-c

    No documented interaction in our data — that is not a safety clearance.

  • AOD-9604 + Alpha-MSH

    No documented interaction in our data — that is not a safety clearance.

  • AOD-9604 + Hexarelin

    No documented interaction in our data — that is not a safety clearance.

  • Alpha-MSH + Hexarelin

    No documented interaction in our data — that is not a safety clearance.

  • Alpha-MSH + Tesamorelin

    No documented interaction in our data — that is not a safety clearance.

  • Alpha-MSH + MK-677

    No documented interaction in our data — that is not a safety clearance.

  • Alpha-MSH + MOTS-c

    No documented interaction in our data — that is not a safety clearance.

  • Alpha-MSH + CJC-1295

    No documented interaction in our data — that is not a safety clearance.

  • Hexarelin + MOTS-c

    No documented interaction in our data — that is not a safety clearance.

  • MK-677 + MOTS-c

    No documented interaction in our data — that is not a safety clearance.

  • MOTS-c + CJC-1295

    No documented interaction in our data — that is not a safety clearance.

Compounds we looked at and left out

These share some biology with this goal, so you may have seen them recommended for it. Here is what our own research says about each.

  • Oxytocinmatched on appetite and satiety

    Oxytocin is linked to appetite and satiety, but in this compound that activity is about uterine contractions and labor induction.

    “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.”— from its own profile
  • Semaglutidematched on fat breakdown

    Semaglutide is linked to fat breakdown, but in this compound that activity is about appetite suppression and overall weight loss.

    “It also acts on appetite regulation and slows the rate at which the stomach empties, leading to reduced food intake and weight loss.”— from its own profile
  • Linaclotidematched on fat breakdown

    Linaclotide is linked to fat breakdown, but none of its 189 research claims address this goal.

  • Cerebrolysinmatched on igf-1 signalling

    Cerebrolysin is linked to igf-1 signalling, but in this compound that activity is about neuroprotection and brain repair.

    “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.”— from its own profile
  • Klothomatched on igf-1 signalling

    Klotho is linked to igf-1 signalling, but in this compound that activity is about anti-aging and longevity (via phosphate/mineral homeostasis and reduction of fibrosis).

    “Klotho blunts IGF-1/Insulin signaling”— from its own profile
  • Humaninmatched on igf-1 signalling

    Humanin is linked to igf-1 signalling, but in this compound that activity is about cellular protection and mitochondrial stress response.

    “Humanin plasma levels are inversely correlated with growth hormone and insulin-like growth factor 1 expression, which may promote accelerated aging”— from its own profile
  • Vilonmatched on igf-1 signalling

    Vilon is linked to igf-1 signalling, but none of its 195 research claims address this goal.

What we can't tell you yet

For this goal, direct human body-composition trials are largely confined to tesamorelin's visceral-fat reduction in HIV-associated lipodystrophy; sermorelin's clinical data are in growth-hormone-deficient children, and the muscle-and-fat effects of the growth-hormone secretagogues, follistatin, MOTS-c and AOD-9604 rest on animal work, single case reports, or lower-tier commentary rather than controlled human trials in healthy adults.

Sources

Ordered as cited above.

  1. Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov
  2. Growth hormone secretagogues: history, mechanism of action, and clinical development(opens in a new tab)
    Tier 1Web · doi.org
  3. Sermorelin (injection route) - Side effects & dosage(opens in a new tab)
    Tier 1Web · mayoclinic.org
  4. MK-677 (Ibutamoren): Research Guide | PtP Wiki(opens in a new tab)
    Tier 1Web · pathtopeptides.com
  5. LGD-4033 and MK-677 use impacts body composition, circulating biomarkers, and skeletal muscle androgenic hormone and receptor content: A case report.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov
  6. Hepatotoxicity induced by MK-677.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov
  7. FDA Presentation – CJC-1295(opens in a new tab)
    Tier 1Web · downloads.regulations.gov
  8. CJC-1295: Research Evidence & Safety Profile | PeptideInsight(opens in a new tab)
    Tier 2Web · peptideinsight.com
  9. CJC 1295(opens in a new tab)
    Tier 3Web · downloads.regulations.gov
  10. Tesamorelin - LiverTox - NCBI Bookshelf(opens in a new tab)
    Tier 1Web · ncbi.nlm.nih.gov
  11. Spotlight on tesamorelin in HIV-associated lipodystrophy.(opens in a new tab)
    Tier 1PubMed · pubmed.ncbi.nlm.nih.gov
  12. CLINICAL PHARMACOLOGY AND BIOPHARMACEUTICS REVIEW(S)(opens in a new tab)
    Tier 1Web · accessdata.fda.gov
  13. The transgenic expression of human follistatin-344 increases skeletal muscle mass in pigs.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov
  14. Follistatin-344: Remove the Brake on Muscle (2026)(opens in a new tab)
    Tier 3Web · thepeptidecatalog.com
  15. Follistatin-344: Myostatin Regulation & Muscle Signaling(opens in a new tab)
    Tier 3Web · newtropin.com
  16. Growth hormone-releasing activity of hexarelin in humans. ...(opens in a new tab)
    Tier 1Web · pubmed.ncbi.nlm.nih.gov
  17. Growth hormone-releasing activity of hexarelin in humans. A dose-response study - PubMed(opens in a new tab)
    Tier 1Web · pubmed.ncbi.nlm.nih.gov
  18. Growth hormone-releasing activity of hexarelin in humans | European Journal of Clinical Pharmacology | Springer Nature Link(opens in a new tab)
    Tier 1Web · link.springer.com
  19. Melanotan II - an overview(opens in a new tab)
    Tier 2Web · sciencedirect.com
  20. Clinical Urology: Original Articles SYNTHETIC MELANOTROPIC PEPTIDE INITIATES ERECTIONS IN MEN WITH PSYCHOGENIC ERECTILE DYSFUNCTION: DOUBLE-BLIND, PLACEBO CONTROLLED CROSSOVER STUDY(opens in a new tab)
    Tier 1Web · sciencedirect.com
  21. What is Melanotan-II - the drug that the TGA urges consumers to avoid?(opens in a new tab)
    Tier 3Web · unsw.edu.au
  22. Protocol for Alpha MSH Infusion Study in Patients With Type 2 Diabetes(opens in a new tab)
    Tier 1Web · clinicaltrials.gov
  23. Alpha-MSH(opens in a new tab)
    Tier 1Web · hra.nhs.uk
  24. AnAt-labeled alpha-melanocyte stimulating hormone peptide analog for targeted alpha therapy of metastatic melanoma.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov
  25. Ipamorelin Research — Selective GH Secretagogue, Preclinical Studies & Safety Profile - Peptide.co(opens in a new tab)
    Tier 2Web · peptide.co
  26. Ipamorelin: Research Evidence & Safety Profile | PeptideInsight(opens in a new tab)
    Tier 2Web · peptideinsight.com
  27. Growth hormone secretagogues: history, mechanism of action, and clinical development(opens in a new tab)
    Tier 2Web · doi.org
  28. The mitochondrial-derived peptide MOTS-c relieves hyperglycemia and insulin resistance in gestational diabetes mellitus.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov
  29. Mitochondrial-derived peptides and exercise.(opens in a new tab)
    Tier 2PubMed · pubmed.ncbi.nlm.nih.gov
  30. MOTS-C Peptide: Separating Science from Hype | adjust.clinic(opens in a new tab)
    Tier 3Web · adjust.clinic
  31. The effects of human GH and its lipolytic fragment (AOD9604) on lipid metabolism following chronic treatment in obese mice and beta(3)-AR knock-out mice - PubMed(opens in a new tab)
    Tier 2Web · pubmed.ncbi.nlm.nih.gov
  32. The effects of human GH and its lipolytic fragment ...(opens in a new tab)
    Tier 2Web · pubmed.ncbi.nlm.nih.gov
  33. AOD 9604 Peptide: Benefits, Dosage, Fat Loss Science & Safety(opens in a new tab)
    Tier 3Web · prymalab.net

This brief reports what published research says about these compounds. It is information, not medical advice, and not a recommendation to use anything described here. Evidence quality varies by compound and is labelled throughout. Talk to a qualified clinician before acting on any of it.