Peptide United

Specimen index

Peptide Database

102 peptides all research profiles

Ipamorelin

Preclinical

NNC 26-0161

Ipamorelin is a selective growth hormone secretagogue and ghrelin receptor agonist. Unlike other GHRPs, it stimulates GH release with high selectivity — producing minimal cortisol, ACTH, or prolactin elevation. It is among the most studied GHRPs for its clean GH pulse profile, making it a preferred research peptide for GH axis studies with reduced side effect concern.

C₃₈H₄₉N₉O₅ · 711.86 Da

Growth Hormone Axis

Kisspeptin-10

Phase II

KP-10 · metastin 45-54

Kisspeptin-10 is the shortest biologically active fragment of the kisspeptin peptide family, which are potent endogenous activators of the hypothalamic GnRH pulse generator. Research demonstrates it stimulates LH and FSH release and has been studied for infertility, hypogonadotropic hypogonadism, and modulating sexual aversion in psychological studies. It represents a key upstream regulator of the reproductive axis.

Sexual Health

KPV

Preclinical

Lys-Pro-Val · α-MSH C-terminal tripeptide

KPV is a tripeptide derived from the C-terminal sequence of alpha-melanocyte-stimulating hormone (α-MSH). It exhibits potent anti-inflammatory effects by inhibiting NF-κB signaling and proinflammatory cytokine production. Research is particularly focused on its potential for inflammatory bowel disease, colitis, and skin inflammation, with studies showing efficacy even when administered orally or topically.

Healing & RecoveryImmune SupportPain & Inflammation

Leuphasyl

Preclinical

Pentapeptide-18

Leuphasyl is a pentapeptide that acts as an enkephalin analog, binding to δ-opioid receptors on muscle cells and neuronal cells to modulate acetylcholine release and reduce muscle contraction. Often combined with Argireline in cosmetic formulations for a synergistic anti-wrinkle effect, studies show the combination outperforms either compound alone in reducing crow's feet and forehead lines.

Skin & Cosmetic

Liraglutide

Approved

Victoza · Saxenda

Liraglutide is a once-daily GLP-1 receptor agonist approved for type 2 diabetes (Victoza) and obesity (Saxenda). It achieves fatty acid attachment to albumin for extended half-life, enabling daily dosing. The LEADER trial established significant cardiovascular mortality benefit in high-risk patients, and research continues into neuroprotective and anti-inflammatory properties beyond metabolic indications.

GLP-1 & Metabolic HormonesFat Loss & MetabolicCardiovascular

LL-37

Phase I

Cathelicidin · hCAP18/LL-37

LL-37 is the only known human cathelicidin antimicrobial peptide, derived from the C-terminus of hCAP18 protein. It exhibits broad-spectrum antimicrobial activity against bacteria, fungi, and viruses by disrupting microbial membranes. Beyond direct killing, LL-37 modulates inflammation, promotes wound healing, and may have anticancer properties. Research focuses on chronic wound care, infection, and skin disorders like rosacea.

AntimicrobialImmune SupportHealing & Recovery

Magainin-2

Preclinical

Magainin II

Magainin-2 is a 23-amino-acid cationic antimicrobial peptide (AMP) isolated from the skin of the African clawed frog (Xenopus laevis). It kills bacteria through membrane disruption — forming toroidal pores in bacterial lipid bilayers — while showing low toxicity to mammalian cells due to differences in membrane composition. It is a key model peptide for AMP research and drug design, with a derivative (pexiganan) evaluated in clinical trials for diabetic foot ulcers.

Antimicrobial

Mechano Growth Factor

Preclinical

MGF · IGF-1Ec

Mechano Growth Factor (MGF) is a splice variant of the IGF-1 gene expressed in response to mechanical loading and muscle damage. Unlike systemic IGF-1, MGF activates satellite cells (muscle stem cells) to proliferate before differentiating — a critical step in muscle repair and growth. Research indicates it plays a distinct, non-overlapping role with systemic IGF-1 in tissue regeneration.

Growth Hormone AxisMuscle & PerformanceHealing & Recovery

Melanotan I

Approved

Afamelanotide · Scenesse

Melanotan I (afamelanotide) is a linear synthetic α-MSH analog with higher selectivity for MC1R than MT-II. FDA-approved as Scenesse for erythropoietic protoporphyria (EPP), where it reduces phototoxic pain by enhancing melanin production and UV protection. Research explores broader applications in vitiligo, polymorphous light eruption, and other photosensitive disorders.

Skin & CosmeticSexual Health

Melanotan II

Preclinical

MT-II · MT2

Melanotan II is a cyclic synthetic analog of α-MSH that non-selectively activates melanocortin receptors (MC1R–MC5R). It induces skin tanning (via MC1R), erectile function (via MC4R), and sexual arousal while also suppressing appetite. It was the precursor compound from which PT-141 was developed. Research continues despite regulatory concerns due to its broad receptor activity profile.

Sexual HealthSkin & Cosmetic

Mod GRF 1-29

Preclinical

CJC-1295 without DAC · Modified GRF 1-29

Mod GRF 1-29 is a modified version of GHRH(1-29) with four amino acid substitutions that increase stability and half-life without the DAC albumin-binding component. It produces a natural, pulsatile GH release and is commonly paired with GHRPs (like Ipamorelin) for a synergistic GH pulse. Its shorter duration preserves natural pituitary feedback mechanisms.

Growth Hormone Axis

MOTS-c

Preclinical

Mitochondrial ORF of the 12S rRNA Type-C

MOTS-c is a 16-amino-acid mitochondria-derived peptide encoded within the 12S rRNA gene. It regulates AMPK signaling, enhances insulin sensitivity, promotes muscle glucose uptake independently of insulin, and improves exercise capacity. Animal studies show it extends lifespan and protects against diet-induced obesity and age-related metabolic dysfunction. It translocates to the nucleus under stress to regulate adaptive gene expression.

Mitochondrial HealthFat Loss & MetabolicAnti-Aging & Longevity

NAP

Phase II

Davunetide · NAPVSIPQ

NAP (NAPVSIPQ) is an 8-amino-acid neuroprotective peptide derived from activity-dependent neuroprotective protein (ADNP). It stabilizes microtubules by interacting with tubulin, protecting neurons against tau pathology, amyloid toxicity, and oxidative damage. Phase 2 trials in schizophrenia and progressive supranuclear palsy have been completed; research is ongoing for Alzheimer's disease and autism spectrum disorder.

NeuroprotectionCognitive Enhancement

Neuropeptide Y

Preclinical

NPY

Neuropeptide Y (NPY) is a 36-amino-acid peptide and the most abundant neuropeptide in the mammalian CNS, acting through Y1–Y6 receptors. It is a potent orexigenic signal (stimulating appetite and fat storage), anxiolytic agent, vasoconstrictor, and regulator of circadian rhythms. Paradoxically, peripheral NPY promotes fat accumulation while central NPY drives food intake — making it a complex but high-priority metabolic research target.

Cognitive EnhancementFat Loss & MetabolicCardiovascular

Neurotensin

Preclinical

NT · NTS

Neurotensin is a 13-amino-acid neuropeptide found in the brain and GI tract. Centrally, it modulates dopamine circuits, acts as an endogenous antipsychotic-like agent, and is analgesic. Peripherally, it inhibits gastric acid secretion, stimulates pancreatic secretion, and promotes fat absorption. Research explores neurotensin analogs for pain, schizophrenia, Parkinson's disease, and metabolic regulation.

Pain & InflammationFat Loss & MetabolicCognitive Enhancement

Noopept

Approved

N-phenylacetyl-L-prolylglycine ethyl ester · GVS-111

Noopept is a dipeptide-derived nootropic approved in Russia for cognitive disorders and memory impairment. It is hydrolyzed in vivo to release cycloprolylglycine, an endogenous neuropeptide. Research demonstrates neuroprotective, memory-enhancing, and anxiolytic effects, upregulation of BDNF and NGF in the hippocampus and cortex, and potential benefits in Alzheimer's disease models. It is significantly more potent than piracetam on a weight-for-weight basis.

Cognitive EnhancementNeuroprotection

Octreotide

Approved

Sandostatin · SMS 201-995

Octreotide is a synthetic 8-amino-acid somatostatin analog with a much longer half-life than native somatostatin. FDA-approved for acromegaly, carcinoid syndrome, VIPomas, and variceal bleeding, it is also used off-label for Cushing's disease, thyroid cancer, and refractory diarrhea. Long-acting release (LAR) formulations allow monthly dosing. It is among the most clinically important peptide drugs in endocrinology.

Growth Hormone AxisGLP-1 & Metabolic Hormones

Orexin A

Preclinical

Hypocretin-1 · OXA

Orexin A (Hypocretin-1) is a 33-amino-acid neuropeptide produced exclusively by lateral hypothalamic neurons. It promotes wakefulness, arousal, and energy expenditure via OX1R and OX2R receptors, and its deficiency (due to autoimmune destruction of orexin neurons) is the cause of narcolepsy with cataplexy. Orexin receptor antagonists (suvorexant, lemborexant) are approved for insomnia; orexin agonists are under development for narcolepsy.

Sleep & CircadianCognitive Enhancement

Oxytocin

Approved

Pitocin · the "bonding hormone"

Oxytocin is a 9-amino-acid neuropeptide produced in the hypothalamus and released by the posterior pituitary. Beyond its classic roles in parturition and lactation, research demonstrates effects on social bonding, trust, empathy, fear extinction, and autism spectrum disorder. Intranasal oxytocin research has produced mixed results in clinical trials, but it remains one of the most studied peptides in social neuroscience.

Cognitive EnhancementSexual Health

P21

Preclinical

P21 cognitive peptide

P21 is a peptide fragment derived from CNTF (Ciliary Neurotrophic Factor) designed to activate the STAT3 signaling pathway, which promotes neurogenesis and cognitive function. Animal research demonstrates improved spatial memory, increased hippocampal neurogenesis, and enhanced BDNF expression. It is studied as a non-cytokine CNTF functional mimetic without the systemic side effects of full-length CNTF.

Cognitive EnhancementNeuroprotection

Palmitoyl Pentapeptide-4

Preclinical

Matrixyl · Pal-KTTKS

Palmitoyl Pentapeptide-4 (Matrixyl) is a lipopeptide widely used in cosmetic anti-aging formulations. It is derived from the procollagen type I sequence and acts as a matrikine, signaling skin cells to produce collagen, elastin, fibronectin, and hyaluronic acid. Clinical studies demonstrate measurable reduction in wrinkle depth and improved skin elasticity with topical application.

Skin & Cosmetic

Palmitoyl Tripeptide-1

Preclinical

Pal-GHK · Matrixyl component

Palmitoyl Tripeptide-1 is a lipopeptide created by palmitoylating GHK (glycyl-histidyl-lysine), the same sequence as GHK-Cu without copper. The palmitoyl group enhances skin penetration, while the GHK sequence signals fibroblasts to upregulate collagen, elastin, and hyaluronic acid synthesis. It is a primary active ingredient in Matrixyl formulations and widely used in anti-aging cosmetics with clinical data supporting wrinkle reduction.

Skin & CosmeticHealing & Recovery

PEG-MGF

Preclinical

PEGylated Mechano Growth Factor

PEG-MGF is a PEGylated (polyethylene glycol-modified) form of Mechano Growth Factor, designed to dramatically extend its biological half-life from minutes to days while preserving activity. PEGylation allows systemic delivery and sustained satellite cell activation without the need for local injection. Research shows enhanced muscle hypertrophy signaling compared to unmodified MGF.

Growth Hormone AxisMuscle & Performance

Peptide YY

Phase II

PYY · PYY3-36

Peptide YY (PYY) is a 36-amino-acid gut hormone released by L-cells postprandially. The truncated form PYY3-36 is the predominant circulating form and acts as a potent satiety signal by inhibiting NPY neurons in the hypothalamic arcuate nucleus. Research and early clinical trials demonstrate that PYY3-36 administration significantly reduces food intake. It represents a key component of gut-brain appetite regulation studied for obesity treatment.

Fat Loss & Metabolic