Peptide Database

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.

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.

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.

Glucose-dependent Insulinotropic Polypeptide · Gastric Inhibitory Polypeptide

GIP is a 42-amino-acid incretin hormone secreted by duodenal K-cells in response to fat and carbohydrate ingestion. Like GLP-1, it enhances glucose-dependent insulin secretion. Unlike GLP-1, it also promotes insulin secretion during hypoglycemia, protects β-cells, and at high doses may stimulate glucagon in a glucose-independent manner. The GIP receptor's role in energy homeostasis underlies the efficacy of dual GIP/GLP-1 agonists like tirzepatide.

Glucagon-like Peptide-1 · GLP-1(7-37)

GLP-1 is an endogenous incretin hormone secreted by intestinal L-cells in response to nutrient ingestion. It enhances glucose-dependent insulin secretion, suppresses glucagon, slows gastric emptying, and signals satiety to the hypothalamus. Native GLP-1 has a half-life of only 1–2 minutes due to DPP-4 degradation, which drove the development of DPP-4-resistant analogs (semaglutide, liraglutide, exenatide) that are now major drug classes.

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.

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.

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.

Alpha-Melanocyte-Stimulating Hormone · α-Melanotropin

α-MSH is an endogenous 13-amino-acid peptide derived from POMC (pro-opiomelanocortin). It activates MC1R to stimulate melanin production in skin, MC4R to suppress appetite and regulate energy expenditure, and MC3R/MC1R to exert potent anti-inflammatory effects. It is the parent compound from which many synthetic melanocortin analogs (Melanotan I, II, PT-141, KPV) were derived and remains a cornerstone of melanocortin pharmacology research.