# AmericanPeptide.com

> AI-powered peptide research reference: a PubChem-enriched catalog of research peptides, indication guides, head-to-head comparisons, clinical-trial intelligence, and an open CC BY 4.0 JSON API.

All catalog data is licensed CC BY 4.0 with attribution to AmericanPeptide.com. Every peptide page has a markdown twin at /catalog/{slug}.md, and the whole catalog is available as one document at /llms-full.txt. This is a research platform, not a medical device — content describes published research, not clinical recommendations.

## Peptide catalog

- [Semaglutide](https://www.americanpeptide.com/catalog/semaglutide.md): Metabolic — Long-acting GLP-1 receptor agonist for glycemic control and weight management.
- [Tirzepatide](https://www.americanpeptide.com/catalog/tirzepatide.md): Metabolic — Dual GIP / GLP-1 receptor agonist with industry-leading weight-loss endpoints.
- [Retatrutide](https://www.americanpeptide.com/catalog/retatrutide.md): Metabolic — Investigational triple agonist (GIP / GLP-1 / glucagon) in late-stage trials.
- [Cagrilintide](https://www.americanpeptide.com/catalog/cagrilintide.md): Metabolic — Long-acting amylin analog studied alongside semaglutide as CagriSema.
- [Insulin (human)](https://www.americanpeptide.com/catalog/insulin.md): Metabolic — The archetypal protein biologic — a 51-amino-acid two-chain hormone, disulfide-linked, and the first recombinant DNA drug ever marketed.
- [Glucagon](https://www.americanpeptide.com/catalog/glucagon.md): Metabolic — Insulin’s counter-hormone — a 29-amino-acid peptide that raises blood glucose, the emergency rescue for severe lows, and the "G" in the new triple agonists.
- [Tesamorelin](https://www.americanpeptide.com/catalog/tesamorelin.md): Growth Hormone / Metabolic — GHRH analog FDA-approved for HIV-associated lipodystrophy.
- [Myostatin (GDF-8)](https://www.americanpeptide.com/catalog/myostatin.md): Growth Hormone / Metabolic — The body’s brake on muscle growth — a TGF-β-family growth factor whose inhibition is the leading strategy to preserve muscle, including during GLP-1 weight loss.
- [Follistatin](https://www.americanpeptide.com/catalog/follistatin.md): Growth Hormone / Metabolic — A natural myostatin and activin antagonist — by neutralizing the muscle brake it is one of the most potent pro-muscle factors studied, and a doping and gene-therapy flashpoint.
- [Apitegromab](https://www.americanpeptide.com/catalog/apitegromab.md): Growth Hormone / Metabolic — A monoclonal antibody that selectively blocks pro/latent myostatin — the muscle brake — studied to preserve lean mass during GLP-1 weight loss.
- [Trevogrumab](https://www.americanpeptide.com/catalog/trevogrumab.md): Growth Hormone / Metabolic — An anti-myostatin antibody (Regeneron) now studied in obesity combinations to cut lean-mass loss and deepen fat loss alongside semaglutide.
- [Emugrobart](https://www.americanpeptide.com/catalog/emugrobart.md): Growth Hormone / Metabolic — A "sweeping" anti-myostatin antibody (Roche/Chugai) that not only blocks but actively clears myostatin — a cautionary case after its rare-disease trials failed.
- [Garetosmab](https://www.americanpeptide.com/catalog/garetosmab.md): Growth Hormone / Metabolic — An anti-activin-A antibody (Regeneron) — closest to approval of the axis (FOP), and a partner in obesity muscle-preservation combinations.
- [Bimagrumab](https://www.americanpeptide.com/catalog/bimagrumab.md): Growth Hormone / Metabolic — An antibody that blocks the activin type II receptor itself — shutting off myostatin AND activin signaling at once; famous for adding muscle while cutting fat.
- [MOTS-c](https://www.americanpeptide.com/catalog/mots-c.md): Mitochondrial / Longevity / Metabolic — Mitochondrially-encoded peptide with reported insulin-sensitizing activity.
- [AOD-9604](https://www.americanpeptide.com/catalog/aod-9604.md): Metabolic — C-terminal hGH fragment (177–191) historically investigated for lipolysis.
- [5-Amino-1MQ](https://www.americanpeptide.com/catalog/5-amino-1mq.md): Metabolic / Longevity — Small-molecule NNMT inhibitor (often catalogued alongside peptides).
- [Somatropin (rHGH)](https://www.americanpeptide.com/catalog/somatropin.md): Growth Hormone / Longevity — Recombinant 191-amino-acid human growth hormone — a folded protein biologic identical in sequence to pituitary GH, not a synthetic research peptide.
- [IGF-1 (Mecasermin)](https://www.americanpeptide.com/catalog/igf-1.md): Growth Hormone / Longevity — The downstream effector of growth hormone — a 70-amino-acid recombinant protein, structurally a cousin of proinsulin, that carries out most of GH’s growth signal.
- [IGF-1 LR3](https://www.americanpeptide.com/catalog/igf-1-lr3.md): Growth Hormone — A long-acting modified IGF-1 analog with reduced IGFBP binding and prolonged systemic activity.
- [MGF (Mechano Growth Factor)](https://www.americanpeptide.com/catalog/mgf.md): Growth Hormone — A splice variant of IGF-1 expressed after muscle damage; studied for satellite-cell activation.
- [CJC-1295 (no DAC)](https://www.americanpeptide.com/catalog/cjc-1295-no-dac.md): Growth Hormone — Modified GHRH(1-29) analog with short plasma half-life.
- [CJC-1295 (with DAC)](https://www.americanpeptide.com/catalog/cjc-1295-with-dac.md): Growth Hormone — Long-acting GHRH analog with a Drug Affinity Complex for albumin binding.
- [Ipamorelin](https://www.americanpeptide.com/catalog/ipamorelin.md): Growth Hormone — Selective ghrelin receptor agonist (GHRP) with minimal cortisol / prolactin release.
- [Sermorelin](https://www.americanpeptide.com/catalog/sermorelin.md): Growth Hormone — Truncated GHRH(1-29) — historically the first GHRH analog approved by the FDA.
- [Hexarelin](https://www.americanpeptide.com/catalog/hexarelin.md): Growth Hormone — Synthetic hexapeptide GHRP with potent GH-releasing activity.
- [BPC-157](https://www.americanpeptide.com/catalog/bpc-157.md): Healing & Repair — Synthetic gastric pentadecapeptide investigated for tendon, ligament, and GI repair.
- [TB-500](https://www.americanpeptide.com/catalog/tb-500.md): Healing & Repair — Synthetic fragment of thymosin β4 studied for cell migration and tissue repair.
- [GHK-Cu](https://www.americanpeptide.com/catalog/ghk-cu.md): Cosmetic / Healing & Repair — Endogenous copper-binding tripeptide widely studied in skin and hair biology.
- [EPO (Erythropoietin)](https://www.americanpeptide.com/catalog/epo.md): Healing & Repair — A glycoprotein hormone that drives red-blood-cell production — a recombinant biologic famous in medicine for treating anemia and infamous in sport for blood doping.
- [Teriparatide (PTH 1-34)](https://www.americanpeptide.com/catalog/teriparatide.md): Healing & Repair / Longevity — The active fragment of parathyroid hormone — a recombinant peptide that builds bone, exploiting a paradox: the same hormone resorbs bone when continuous, but builds it when pulsed.
- [LL-37](https://www.americanpeptide.com/catalog/ll-37.md): Immune / Healing & Repair — Human cathelicidin antimicrobial peptide active across bacteria, fungi, and viruses.
- [KPV](https://www.americanpeptide.com/catalog/kpv.md): Immune / Healing & Repair — Anti-inflammatory C-terminal tripeptide of α-MSH.
- [Semax](https://www.americanpeptide.com/catalog/semax.md): Cognitive — Russian synthetic ACTH(4-10) analog studied for nootropic and neuroprotective effects.
- [Selank](https://www.americanpeptide.com/catalog/selank.md): Cognitive — Synthetic heptapeptide analog of tuftsin investigated as an anxiolytic.
- [DSIP](https://www.americanpeptide.com/catalog/dsip.md): Cognitive — Endogenous nonapeptide first isolated for its sleep-promoting properties.
- [Oxytocin](https://www.americanpeptide.com/catalog/oxytocin.md): Reproductive / Cognitive — A 9-amino-acid cyclic hormone of labor and bonding — historically the first peptide hormone ever chemically synthesized, and the most over-marketed "love hormone."
- [SS-31](https://www.americanpeptide.com/catalog/ss-31.md): Mitochondrial / Longevity — Mitochondria-targeted cardiolipin-binding tetrapeptide.
- [Epitalon](https://www.americanpeptide.com/catalog/epitalon.md): Longevity — Synthetic tetrapeptide investigated for telomerase activity and circadian effects.
- [NAD+](https://www.americanpeptide.com/catalog/nad-plus.md): Mitochondrial / Longevity — Essential redox cofactor central to mitochondrial bioenergetics and sirtuin activity.
- [AHK-Cu](https://www.americanpeptide.com/catalog/ahk-cu.md): Cosmetic — Copper-binding tripeptide (Ala-His-Lys) studied for hair-follicle stimulation and dermal repair.
- [Matrixyl (Palmitoyl Pentapeptide-4)](https://www.americanpeptide.com/catalog/matrixyl.md): Cosmetic — Palmitoylated matrikine peptide that signals fibroblasts to synthesize collagen — contains no copper.
- [Melanotan II](https://www.americanpeptide.com/catalog/melanotan-2.md): Cosmetic / Reproductive — Synthetic cyclic analog of α-MSH; non-selective melanocortin receptor agonist.
- [Afamelanotide](https://www.americanpeptide.com/catalog/melanotan-1.md): Cosmetic — MC1R-selective α-MSH analog; FDA-approved (Scenesse) for photoprotection in erythropoietic protoporphyria.
- [PT-141](https://www.americanpeptide.com/catalog/pt-141.md): Reproductive — Melanocortin-4 receptor agonist FDA-approved for HSDD in premenopausal women.
- [Kisspeptin-10](https://www.americanpeptide.com/catalog/kisspeptin-10.md): Reproductive — C-terminal decapeptide fragment of kisspeptin; potent GnRH secretagogue.
- [HCG](https://www.americanpeptide.com/catalog/hcg.md): Reproductive — A heterodimeric glycoprotein hormone — two different glycosylated subunits — that mimics the LH surge; the pregnancy hormone, also the subject of a debunked diet.
- [FSH (Follitropin)](https://www.americanpeptide.com/catalog/fsh.md): Reproductive — A heterodimeric glycoprotein gonadotropin that drives follicle growth and spermatogenesis — the workhorse of IVF stimulation, and a sister molecule to HCG and LH.
- [Thymosin Alpha-1](https://www.americanpeptide.com/catalog/thymosin-alpha-1.md): Immune — Thymus-derived 28-amino-acid peptide approved in many countries as an immunomodulator.

## Research area guides

- [Weight Loss & Metabolic Health](https://www.americanpeptide.com/research-areas/weight-loss): Incretin and metabolic peptides studied for glycemic control and fat loss.
- [Wound Healing & Tissue Repair](https://www.americanpeptide.com/research-areas/wound-healing): Regenerative peptides studied for soft-tissue, tendon, and vascular repair.
- [Cognition & Neuroprotection](https://www.americanpeptide.com/research-areas/cognition-neuroprotection): Nootropic and neurotrophic peptides studied for cognition and recovery.
- [Anxiety, Mood & Stress](https://www.americanpeptide.com/research-areas/anxiety-mood): Regulatory peptides studied for anxiolysis and stress-axis modulation.
- [Sleep & Circadian Rhythm](https://www.americanpeptide.com/research-areas/sleep-circadian): Peptides studied for sleep architecture and circadian regulation.
- [Longevity & Aging](https://www.americanpeptide.com/research-areas/longevity-aging): Peptides studied across the aging axis — senescence, NAD+, and resilience.
- [Growth Hormone & Body Composition](https://www.americanpeptide.com/research-areas/growth-hormone-axis): Secretagogues studied for GH release, IGF-1, and body composition.
- [Skin & Hair](https://www.americanpeptide.com/research-areas/skin-hair): Peptides studied for skin aging, pigmentation, and hair follicle biology.
- [Sexual & Reproductive Health](https://www.americanpeptide.com/research-areas/sexual-reproductive): Peptides studied across the HPG axis and CNS sexual-response pathways.
- [Immune & Inflammation](https://www.americanpeptide.com/research-areas/immune-inflammation): Thymic and host-defense peptides studied for immune modulation.
- [Mitochondrial & Bioenergetics](https://www.americanpeptide.com/research-areas/mitochondrial): Mitochondria-targeted peptides studied for bioenergetics and cardiolipin.

## Comparisons

- [Semaglutide vs Tirzepatide](https://www.americanpeptide.com/compare/semaglutide-vs-tirzepatide): Research comparison of semaglutide (Ozempic/Wegovy) and tirzepatide (Mounjaro/Zepbound) — mechanism differences (GLP-1R mono vs GIP/GLP-1R dual agonism), head-to-head trial data, synthesis complexity, and the case for retatrutide.
- [CJC-1295 vs Ipamorelin](https://www.americanpeptide.com/compare/cjc-1295-vs-ipamorelin): Research comparison of CJC-1295 (no DAC / with DAC) and ipamorelin — receptor differences (GHRHR vs GHS-R1a), why they are studied together, pulsatile vs sustained release, and compound profiles.
- [BPC-157 vs TB-500](https://www.americanpeptide.com/compare/bpc-157-vs-tb-500): Research comparison of BPC-157 and TB-500 — distinct repair mechanisms (angiogenesis/cytoprotection vs actin regulation and cell migration), origins, evidence base, and why they are often studied together.
- [Retatrutide vs Tirzepatide](https://www.americanpeptide.com/compare/retatrutide-vs-tirzepatide): Research comparison of retatrutide (GIP/GLP-1/glucagon triple agonist) and tirzepatide (GIP/GLP-1 dual agonist) — what the glucagon arm adds, trial weight-loss data, and approval status.
- [CJC-1295 vs Sermorelin](https://www.americanpeptide.com/compare/cjc-1295-vs-sermorelin): Both are GHRH analogs that prompt natural GH release. Sermorelin is the short-acting GHRH(1-29) fragment; CJC-1295 with DAC binds albumin for a multi-day half-life. A cited research comparison.
- [Ipamorelin vs Hexarelin](https://www.americanpeptide.com/compare/ipamorelin-vs-hexarelin): Both are GHRPs acting on the ghrelin receptor. Ipamorelin releases GH cleanly without raising cortisol or prolactin; hexarelin is more potent but less selective. A cited research comparison.
- [Semax vs Selank](https://www.americanpeptide.com/compare/semax-vs-selank): Semax (an ACTH(4-10) analog) is studied for cognition and BDNF; Selank (a tuftsin analog) for anxiety via GABA / serotonin. A cited research comparison of the two Russian neuropeptides.
- [PT-141 vs Kisspeptin](https://www.americanpeptide.com/compare/pt-141-vs-kisspeptin): PT-141 (bremelanotide) acts on brain melanocortin receptors for acute arousal; kisspeptin drives the upstream GnRH hormone axis. A cited research comparison of two approaches to sexual function.
- [Melanotan II vs Melanotan I (Afamelanotide)](https://www.americanpeptide.com/compare/melanotan-2-vs-melanotan-1): Afamelanotide (Melanotan I) is MC1R-selective and FDA-approved; Melanotan II is non-selective and activates MC4R, driving side effects. A cited melanocortin research comparison.
- [GHK-Cu vs AHK-Cu](https://www.americanpeptide.com/compare/ghk-cu-vs-ahk-cu): GHK-Cu and AHK-Cu share copper-binding chemistry but target different tissue — skin remodeling vs the hair follicle. How they compare, and where the non-copper peptide Matrixyl fits. Cited.
- [IGF-1 LR3 vs MGF](https://www.americanpeptide.com/compare/igf-1-lr3-vs-mgf): IGF-1 LR3 is a long-acting systemic IGF-1 analog studied for hypertrophy; MGF is a local IGF-1 splice variant studied for satellite-cell activation. A cited research comparison.
- [Epitalon vs MOTS-c](https://www.americanpeptide.com/compare/epitalon-vs-mots-c): Two longevity peptides, two mechanisms: Epitalon is studied for telomerase upregulation, MOTS-c for mitochondrial and metabolic regulation. A cited research comparison.

## Guides & reference

- [GLP-1 & metabolic peptides](https://www.americanpeptide.com/glp-1): the incretin class — semaglutide, tirzepatide, retatrutide.
- [BPC-157](https://www.americanpeptide.com/bpc-157): deep dive on the most-discussed healing peptide.
- [Growth hormone peptides](https://www.americanpeptide.com/gh-peptides): GHRH analogs and secretagogues.
- [Cognitive peptides](https://www.americanpeptide.com/cognitive-peptides): nootropic and neurotrophic compounds.
- [Longevity peptides](https://www.americanpeptide.com/longevity-peptides): aging-axis research compounds.
- [Immune peptides](https://www.americanpeptide.com/immune-peptides): thymic peptides and immunomodulators.
- [Melanocortin hub](https://www.americanpeptide.com/melanocortin): melanocortin receptor agonist research.
- [How peptides are made](https://www.americanpeptide.com/synthesis): synthesis, purification, lyophilization, QC, and reading a COA.
- [Evidence hierarchy](https://www.americanpeptide.com/learn/evidence-hierarchy): how to weigh peptide research quality.
- [Peptide compatibility](https://www.americanpeptide.com/learn/compatibility): which research peptides are commonly co-studied.
- [Glossary](https://www.americanpeptide.com/glossary): 118 defined terms across dosing, chemistry, biology, identifiers, and research.

## API & data

- [Developer docs](https://www.americanpeptide.com/developers): free, open JSON API — query by category, research area, or slug. No key required.
- [Full catalog JSON](https://www.americanpeptide.com/api/catalog): every peptide, PubChem-enriched, CC BY 4.0.
- [Full catalog markdown](https://www.americanpeptide.com/llms-full.txt): the entire catalog as one markdown document.
- MCP server (Streamable HTTP): https://www.americanpeptide.com/api/mcp — connect from Claude, ChatGPT, Cursor, or any MCP client for live tools: search_peptides, get_peptide, get_research_area, compare_peptides, search_clinical_trials, search_pubmed, search_pubchem.

## Optional

- [Clinical trials dashboard](https://www.americanpeptide.com/trials): live ClinicalTrials.gov intelligence.
- [Compound search](https://www.americanpeptide.com/compounds): PubChem-backed compound explorer.
- [Reconstitution calculator](https://www.americanpeptide.com/tools/reconstitution-calculator): research-prep math.

---

Source: AmericanPeptide.com — https://www.americanpeptide.com
Data license: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Attribution: AmericanPeptide.com.
Research reference only — computational and educational content, not medical advice.