Peptide Database

Beta-Alanyl-N-methyl-L-histidine

Anserine is a methylated dipeptide analog of carnosine found in high concentrations in avian and fish muscle. It shares carnosine's pH-buffering and antioxidant properties but shows superior blood-brain barrier penetration. Research highlights potential for cognitive decline prevention, reduction of amyloid-beta toxicity, and improved exercise performance. It is often studied alongside carnosine for synergistic effects.

Acetyl Hexapeptide-3 · Acetyl Hexapeptide-8

Argireline is a synthetic hexapeptide derived from the N-terminal sequence of SNAP-25 protein, a key component of the SNARE complex that mediates acetylcholine release at neuromuscular junctions. It competitively inhibits neurotransmitter vesicle docking, reducing muscle contraction and expression-line formation. Often called "topical Botox," clinical studies show measurable reductions in peri-orbital wrinkle depth with consistent use.

Body Protection Compound 157 · PL 14736

BPC-157 is a 15-amino-acid peptide fragment derived from human gastric juice. It is one of the most extensively researched peptides for tissue repair, demonstrating accelerated healing of tendons, ligaments, muscle, bone, and gut lining in animal models. It appears to upregulate growth hormone receptors and promote angiogenesis at injury sites.

C₆₂H₉₈N₁₆O₂₂ · 1419.55 Da

BK · Kallidin precursor fragment

Bradykinin is a 9-amino-acid vasoactive peptide of the kinin-kallikrein system. It produces vasodilation, increased vascular permeability, pain, and inflammation by acting on B1 and B2 receptors. ACE inhibitors (a major drug class) lower blood pressure partly by preventing bradykinin degradation. Icatibant, a B2 antagonist, is approved for hereditary angioedema. Research also implicates bradykinin in COVID-19 pathology (bradykinin storm hypothesis).

Beta-Alanyl-L-Histidine · L-Carnosine

Carnosine is a naturally occurring dipeptide (β-alanyl-L-histidine) found at high concentrations in skeletal muscle and the brain. It acts as a pH buffer in muscle (reducing acidosis during high-intensity exercise), a powerful antioxidant, an antiglycation agent (preventing protein-sugar crosslinking), and a chelator of zinc and copper. Research explores its role in aging, cognitive decline, autism, and exercise performance.

CCK · CCK-8

Cholecystokinin (CCK) is a peptide hormone produced by duodenal I-cells and neurons in the CNS. It triggers gallbladder contraction, pancreatic enzyme secretion, and potently suppresses appetite via vagal nerve CCK1 receptors. In the brain, CCK neurons modulate anxiety, pain, memory consolidation, and dopamine release. CCK antagonists are studied for anxiety and pain; CCK agonists for obesity and eating disorders.

CJC-1295 with DAC · DAC:GRF

CJC-1295 is a modified GHRH analog with a Drug Affinity Complex (DAC) that binds to serum albumin, dramatically extending its half-life compared to native GHRH. It produces sustained elevation of GH and IGF-1 levels over days rather than hours. Research focuses on body composition improvements, muscle growth, and fat loss through prolonged GH axis stimulation.

C₁₅₂H₂₅₂N₄₂O₄₂S · 3647.28 Da

Hydrolyzed Collagen · Collagen Hydrolysate

Hydrolyzed collagen peptides are short-chain amino acid sequences (2–20 amino acids) produced by enzymatic hydrolysis of collagen. Research demonstrates that specific collagen dipeptides and tripeptides (Pro-Hyp, Hyp-Gly) are absorbed intact, reach fibroblasts in skin and joints, and stimulate collagen and hyaluronic acid synthesis. Meta-analyses support effects on skin elasticity, wrinkle depth, joint pain, and muscle mass when combined with resistance exercise.

Ala-Glu-Asp-Pro · AEDP

Cortagen is a synthetic tetrapeptide (Ala-Glu-Asp-Pro) characterized as a cortex cytoprotective peptide in research from the St. Petersburg Institute. It penetrates the blood-brain barrier and is reported to regulate neuronal gene expression, protect cortical neurons, and improve cognitive function in aging models. It is often studied alongside other peptide bioregulators from the same research group.

Corticotropin-Releasing Hormone · Corticotropin-Releasing Factor

CRH is a 41-amino-acid neuropeptide produced in the hypothalamus that drives the HPA axis stress response. It stimulates ACTH release from the anterior pituitary, ultimately triggering cortisol secretion. Beyond stress regulation, CRH receptors (CRHR1, CRHR2) are distributed throughout the brain and gut, mediating anxiety, depression, immune function, and GI motility. CRH antagonists are under development for anxiety, depression, and irritable bowel syndrome.

Human Neutrophil Peptides (HNP-1, HNP-2, HNP-3) · α-defensins

Alpha-defensins are cationic antimicrobial peptides secreted by neutrophils (HNP-1 to 4) and Paneth cells (HD-5, HD-6) in the small intestine. They kill bacteria, fungi, and enveloped viruses through membrane disruption and also function as chemokines, recruiting immune cells and bridging innate and adaptive immunity. Paneth cell alpha-defensins (HD-5, HD-6) play a critical role in shaping intestinal microbiome composition.

N-hexanoic-Tyr-Ile-(6) aminohexanoic amide · PNB-0408

Dihexa is a small peptide derived from angiotensin IV that acts as a potent agonist at the HGF/c-Met receptor system, which mediates synaptogenesis — the formation of new synaptic connections. Animal studies suggest it may be several orders of magnitude more potent than BDNF at promoting synapse formation. Research focuses on Alzheimer's disease, cognitive decline, and traumatic brain injury.

Delta Sleep Inducing Peptide · Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu

DSIP (Delta Sleep Inducing Peptide) is a nonapeptide first isolated from rabbit cerebral venous blood during electrically induced sleep. Research shows it promotes slow-wave sleep, reduces pain sensitivity, normalizes circadian rhythms, lowers cortisol, and exhibits stress-protective effects. It also stimulates LH release and may influence GH pulsatility. Multiple mechanisms of action are proposed; its receptor has not been fully characterized.

ET-1 · Big endothelin-1

Endothelin-1 (ET-1) is a 21-amino-acid vasoconstrictor peptide produced primarily by vascular endothelial cells. It is the most potent endogenous vasoconstrictor known, acting through ETA and ETB receptors on vascular smooth muscle and endothelium. Elevated ET-1 is implicated in pulmonary arterial hypertension, heart failure, and renal disease — driving the development of endothelin receptor antagonists (bosentan, ambrisentan, macitentan) as clinical drugs.

Leu-Enkephalin · Met-Enkephalin

Enkephalins are endogenous opioid pentapeptides (Met-enkephalin and Leu-enkephalin) acting as natural ligands for delta and mu opioid receptors. They modulate pain, mood, reward, and immune function. Low-dose naltrexone (LDN) works partly by transiently blocking opioid receptors to upregulate enkephalin production. Methionine enkephalin (met-enkephalin) has shown immune-modulating and anti-tumor properties in research, particularly for HIV and cancer.

Epitalon · Epithalamin

Epithalon is a synthetic tetrapeptide (Ala-Glu-Asp-Gly) modeled on the endogenous pineal peptide epithalamin. It is one of the most extensively studied longevity peptides, with Russian research demonstrating telomerase activation, telomere elongation, melatonin normalization, and extended lifespan in animal models. Long-term human studies show reduced all-cause mortality rates and improved biomarkers of aging.

FST-344 · Follistatin isoform 344

Follistatin-344 is an isoform of follistatin, an endogenous glycoprotein that binds and neutralizes myostatin (GDF-8) and activin, thereby releasing the natural inhibition on muscle growth. Without myostatin's inhibitory signal, satellite cells proliferate and muscle fiber hypertrophy is dramatically enhanced. Gene therapy studies in animals and in rare myostatin-null humans demonstrate extreme muscle mass increases, driving significant research interest.

Proxofim

FOXO4-DRI is a D-retro-inverso peptide that disrupts the interaction between FOXO4 and p53 in senescent cells, triggering selective apoptosis of senescent cells (senolysis) while leaving healthy cells unaffected. Mouse studies demonstrated restoration of fitness, fur density, and renal function after treatment. It represents a first-in-class peptide senolytic, establishing proof-of-concept for peptide-mediated clearance of the senescent cell burden.

HGH Frag 176-191 · Growth Hormone Fragment 176-191

Fragment 176-191 is the C-terminal amino acid sequence 176–191 of human growth hormone, closely related to AOD-9604. It mimics the lipolytic activity of natural GH without binding to the GH receptor, thus avoiding insulin resistance and proliferative effects. Research shows it reduces fat mass in animal models by enhancing fat metabolism and inhibiting new fat formation.

GAL

Galanin is a 29-30 amino acid neuropeptide widely distributed throughout the CNS and peripheral nervous system. It modulates memory, mood, pain, seizures, appetite, and sleep via three receptor subtypes (GALR1–3). Research focuses on its roles in Alzheimer's disease (galanin hyperinnervation of cholinergic neurons), depression, epilepsy, and eating behavior. Both agonists and antagonists have therapeutic potential depending on the target condition.

Growth Differentiation Factor 11 · Bone Morphogenetic Protein 11

GDF-11 is a member of the TGF-β superfamily that generated significant excitement when studies reported it as a "rejuvenating factor" in young parabiosis mouse blood. Subsequent research has been highly contested — some studies suggest it reverses cardiac hypertrophy and restores skeletal muscle and neural stem cell function in aged mice, while others find it increases with age and impairs muscle regeneration. It remains one of the most debated factors in aging biology.

Copper Peptide GHK · Glycyl-L-histidyl-L-lysine copper

GHK-Cu is a naturally occurring copper-binding tripeptide found in human plasma, saliva, and urine. Research demonstrates it stimulates collagen, elastin, and glycosaminoglycan synthesis, promotes wound healing, reduces inflammation, and activates protective antioxidant genes. Plasma levels decline with age, making it a significant anti-aging research target.

C₁₄H₂₄CuN₆O₄ · 340.84 Da (free ligand)

Motilin-related peptide · Growth hormone secretagogue

Ghrelin is a 28-amino-acid acylated peptide hormone primarily produced by gastric X/A-like cells and is the endogenous ligand for the growth hormone secretagogue receptor (GHS-R1a). It stimulates GH release, increases appetite and food intake, promotes energy storage, and modulates sleep and mood. Research explores ghrelin axis manipulation for obesity, cachexia, heart failure, and neurodegenerative diseases.

Growth Hormone-Releasing Hormone · Somatoliberin

GHRH is the endogenous 44-amino-acid hypothalamic peptide that drives the pulsatile secretion of growth hormone from the anterior pituitary. Native GHRH acts through GHRHR, stimulating GH gene transcription and secretion. It has a very short half-life in vivo, making it impractical as a therapeutic — which drove the development of modified analogs like sermorelin, CJC-1295, and tesamorelin. Research into GHRH receptor signaling underpins the entire GH secretagogue drug class.