Peptide Glossary — A-Z Reference

A

Acetyl Hexapeptide-3 (Argireline): A synthetic hexapeptide that mimics the N-terminal fragment of SNAP-25, a protein involved in the neuromuscular junction. Studied in cosmetic research for reducing the appearance of expression line… Read more →
ACTH (Adrenocorticotropic Hormone): A 39-amino-acid peptide hormone produced by the anterior pituitary gland in response to CRH. Its primary role is to stimulate cortisol production by the adrenal cortex. Short ACTH fragments such as… Read more →
AHK-Cu (Alanine-Histidine-Lysine Copper Peptide): A tripeptide copper complex naturally formed from the breakdown of histatin-5. Research suggests it promotes hair follicle growth and scalp health through similar pathways to GHK-Cu, but with poten… Read more →
AICAR (5-Aminoimidazole-4-carboxamide ribonucleotide): A cell-permeable AMPK (AMP-activated protein kinase) activator studied as a metabolic exercise mimetic. Preclinical research in animals showed improvements in endurance, fat oxidation, and insulin … Read more →
Alarelin (Alarelin Acetate): A synthetic GnRH (gonadotropin-releasing hormone) decapeptide analogue. Stimulates the pituitary to release LH and FSH. Primarily used in veterinary medicine to induce ovulation and studied in repr… Read more →
Alpha-MSH (Alpha-Melanocyte-Stimulating Hormone): A 13-amino-acid peptide derived by post-translational cleavage of POMC (pro-opiomelanocortin). Acts on melanocortin receptors MC1R–MC5R to regulate skin pigmentation, appetite, inflammation, and se… Read more →
Amino Acid: The fundamental molecular building blocks of peptides and proteins. Twenty standard amino acids are encoded by the human genome, each containing a central carbon atom bonded to an amino group (–NH₂… Read more →
Angiogenesis: The physiological process of forming new blood vessels from pre-existing vasculature. Critical to tissue repair, wound healing, and tumor growth. BPC-157 is noted for its pro-angiogenic effects in … Read more →
AOD-9604 (Anti-Obesity Drug 9604): A modified fragment of human growth hormone (HGH) spanning amino acids 176–191. Research in animal models suggests it may stimulate fat metabolism without affecting blood sugar or cell proliferation. Read more →
ARA-290 (Cibinetide): A non-erythropoietic helix B surface peptide (HBSP) derived from erythropoietin (EPO). Selectively activates the innate repair receptor (IRR) without triggering erythropoiesis or vascular side effe… Read more →

B

Bacteriostatic Water (BW): Sterile water for injection containing 0.9% benzyl alcohol as a preservative. The standard diluent for reconstituting lyophilized research peptides. The benzyl alcohol inhibits bacterial growth, al… Read more →
BAM-15 (BAM15): A mitochondria-targeted protonophore studied as a metabolic uncoupler and anti-obesity compound in preclinical models. Not a peptide itself, but frequently discussed alongside mitochondria-derived … Read more →
Bioavailability: The fraction of an administered dose that reaches systemic circulation in an active form. Most peptides have near-zero oral bioavailability due to degradation by gastric proteases. Subcutaneous (SC… Read more →
Blood-Brain Barrier (BBB): A highly selective semipermeable membrane formed by tightly connected endothelial cells lining brain capillaries, supported by astrocytes and pericytes. It restricts most peptides from entering the… Read more →
BPC-157 (Body Protective Compound-157): A 15-amino-acid synthetic peptide derived from a protein found in human gastric juice. One of the most extensively studied research peptides, with animal models showing effects on tissue repair, gu… Read more →
Bradykinin: A 9-amino-acid vasoactive peptide generated by the kinin-kallikrein system from the precursor kininogen. Causes vasodilation, increased vascular permeability, and pain sensitization. Plays a role i… Read more →
Bremelanotide (PT-141): The International Nonproprietary Name (INN) for PT-141. FDA-approved in 2019 under the brand name Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women. A melanocortin recepto… Read more →

C

Cagrilintide: A long-acting amylin analogue peptide developed by Novo Nordisk. Amylin is a pancreatic hormone co-secreted with insulin that suppresses glucagon, slows gastric emptying, and promotes satiety via a… Read more →
CagriSema (Cagrilintide + Semaglutide): An investigational fixed-dose combination of cagrilintide (amylin receptor agonist) and semaglutide (GLP-1 receptor agonist) in development by Novo Nordisk. Phase 3 trials (REDEFINE program) are ev… Read more →
Certificate of Analysis (COA) (COA): A formal document issued by an independent analytical laboratory confirming the identity, purity, and physical characteristics of a specific peptide batch. A legitimate COA includes: peptide sequen… Read more →
CJC-1295: A synthetic analogue of growth hormone-releasing hormone (GHRH). Research shows it stimulates the pituitary gland to release growth hormone. Often studied in combination with Ipamorelin. Read more →
CJC-1295 + Ipamorelin (GHRH + GHRP Combination): A research protocol combining two complementary growth hormone-stimulating peptides: CJC-1295 (a GHRH analogue acting on GHRH receptors) and Ipamorelin (a GHRP acting on the ghrelin/GHS-R1a recepto… Read more →
CJC-1295 DAC (CJC-1295 with Drug Affinity Complex): A long-acting GHRH analogue that uses the Drug Affinity Complex (DAC) technology to bind covalently to albumin in the bloodstream, dramatically extending its half-life to approximately 6–8 days. Pr… Read more →
Collagen Peptide (Hydrolyzed Collagen): Short peptides (primarily dipeptides and tripeptides such as Pro-Hyp and Hyp-Gly) derived from enzymatic hydrolysis of collagen. Oral supplementation studies suggest potential benefits for skin ela… Read more →
Cortagen (Cortagen (Ala-Glu-Asp-Pro)): A tetrapeptide developed by the St. Petersburg Institute of Bioregulation and Gerontology in Russia. Derived from vascular tissue extracts. Studied for effects on blood vessel regeneration, arteria… Read more →
Cytokine: A broad category of small secreted proteins and glycoproteins that function as intercellular signaling molecules in the immune system. Includes interleukins (IL-1, IL-6, IL-10), tumor necrosis fact… Read more →

D

DAC (Drug Affinity Complex): A peptide modification technology that introduces a reactive maleimidopropionic acid (MPA) group into the peptide chain, enabling covalent binding to cysteine-34 of albumin in the bloodstream. Used… Read more →
Dermorphin: A heptapeptide isolated from the skin secretion of South American frogs of the genus Phyllomedusa. A potent, highly selective μ-opioid receptor agonist approximately 30–40 times more potent than mo… Read more →
Dihexa (PNB-0408): A small, orally bioavailable angiotensin IV analogue (N-hexanoic-Tyr-Ile-(6) aminohexanoic amide). Research in aged rodents demonstrated significant improvements in working memory and spatial learn… Read more →
DSIP (Delta Sleep-Inducing Peptide): A naturally occurring 9-amino-acid neuropeptide first isolated from the cerebral venous blood of rabbits. Studied for its effects on sleep regulation, stress response, and endocrine function. Resea… Read more →

E

EC50 (Half-Maximal Effective Concentration): The concentration of a compound that produces 50% of its maximum possible effect. A key pharmacological metric used to quantify peptide potency at target receptors. A lower EC50 indicates higher po… Read more →
Elamipretide (SS-31 / MTP-131): The INN for SS-31 (Szeto-Schiller peptide 31), a mitochondria-targeted aromatic-cationic tetrapeptide developed by Stealth BioTherapeutics. Concentrates ~1000-fold in the inner mitochondrial membra… Read more →
Endomorphin (Endomorphin-1 / Endomorphin-2): Tetrapeptide endogenous opioids (Tyr-Pro-Trp-Phe-NH₂ and Tyr-Pro-Phe-Phe-NH₂) with the highest known affinity and selectivity for μ-opioid receptors among natural opioid peptides. Studied for pain … Read more →
Epitalon (Epithalon / Epithalone): An alternate spelling of Epithalon (also spelled Epithalone). A synthetic tetrapeptide (Ala-Glu-Asp-Gly) derived from Epithalamin, a bovine pineal gland extract, developed at the St. Petersburg Ins… Read more →
Epithalon (Epitalon (Epithalamin)): A tetrapeptide (Ala-Glu-Asp-Gly) derived from the pineal gland extract Epithalamin. Research in animal models has focused on its potential effects on telomere length and aging biomarkers. Read more →

F

Fibroblast: The primary structural cell of connective tissue, responsible for synthesizing extracellular matrix components including collagen, elastin, fibronectin, and glycosaminoglycans. Central to wound hea… Read more →
Follistatin-315 (FST-315): A shorter isoform of follistatin produced by alternative mRNA splicing. Unlike FST-344, it has reduced binding to heparan sulfate proteoglycans, giving it broader systemic distribution. Studied alo… Read more →
Follistatin-344 (FST-344): A 344-amino-acid isoform of follistatin, an endogenous glycoprotein that binds and neutralizes myostatin (GDF-8) and activin A. Preclinical research in mice showed dramatic muscle mass increases wi… Read more →

G

GDF-11 (Growth Differentiation Factor-11): A member of the TGF-β superfamily closely related to myostatin (GDF-8). Early studies in parabiosis models suggested it might reverse cardiac and skeletal muscle aging, generating significant longe… Read more →
GHK (Glycyl-L-Histidyl-L-Lysine): The tripeptide core of GHK-Cu, found naturally in human plasma, saliva, and urine. Concentrations decline with age (200 ng/mL at age 20 vs. 80 ng/mL at age 60). Research by Loren Pickart has docume… Read more →
GHK-Cu (Copper Peptide GHK-Cu): A naturally occurring copper complex (glycyl-l-histidyl-l-lysine) found in human plasma, saliva, and urine. Research suggests roles in wound healing, skin remodeling, and anti-inflammatory activity. Read more →
Ghrelin: A 28-amino-acid orexigenic (appetite-stimulating) peptide produced primarily by X/A-like cells in the gastric fundus. The endogenous ligand for the growth hormone secretagogue receptor-1a (GHS-R1a)… Read more →
GHRH (Growth Hormone-Releasing Hormone): A 44-amino-acid hypothalamic neuropeptide that stimulates the synthesis and pulsatile secretion of growth hormone from the anterior pituitary somatotroph cells. The natural hormone that CJC-1295 an… Read more →
GHRP-2 (Growth Hormone Releasing Peptide-2): A synthetic agonist of the ghrelin receptor that stimulates growth hormone secretion from the pituitary. Research shows strong GH release with less hunger stimulation than GHRP-6. Read more →
GHRP-6 (Growth Hormone Releasing Peptide-6): A hexapeptide that stimulates growth hormone release via ghrelin receptor activation. One of the first synthetic GH secretagogues studied. Notable for significant appetite stimulation in research m… Read more →
GIP (Glucose-Dependent Insulinotropic Polypeptide): A 42-amino-acid incretin hormone secreted by intestinal K-cells in response to fat and carbohydrate ingestion. Stimulates glucose-dependent insulin secretion from pancreatic β-cells and exerts anab… Read more →
GLP-1 (Glucagon-Like Peptide-1): A 30-amino-acid incretin hormone secreted by intestinal L-cells in response to food intake. Acts on GLP-1 receptors in the pancreas, brain, heart, and gastrointestinal tract. Stimulates glucose-dep… Read more →
GLP-1 Peptides (GLP-1 Receptor Agonists): A class of peptide compounds that activate the glucagon-like peptide-1 receptor (GLP-1R). Includes native GLP-1 (half-life ~2 min) and pharmaceutical analogues engineered for longer duration: exena… Read more →
GLP-1/GIP Dual Agonist (Twincretin): A compound class that simultaneously activates both the GLP-1 receptor and the GIP receptor. Tirzepatide (Mounjaro/Zepbound) is the first and currently only FDA-approved dual agonist in this class.… Read more →
GnRH (Gonadotropin-Releasing Hormone): A 10-amino-acid hypothalamic neuropeptide that stimulates the pituitary to secrete LH (luteinizing hormone) and FSH (follicle-stimulating hormone). The basis for peptides such as triptorelin, leupr… Read more →
Growth Hormone (Somatotropin (GH/hGH)): A 191-amino-acid single-chain peptide hormone produced and secreted by somatotroph cells of the anterior pituitary. Regulates body composition, cell reproduction, and metabolism. Stimulates IGF-1 p… Read more →
Growth Hormone Secretagogue (GHS): A class of compounds that stimulate growth hormone release by activating the ghrelin receptor (GHS-R1a). Includes peptide GHRPs (GHRP-2, GHRP-6, Ipamorelin, Hexarelin) and non-peptide compounds (MK… Read more →

H

Half-Life (t½): The time required for a compound's concentration in the body to decrease by 50%. A fundamental pharmacokinetic parameter that determines dosing frequency. Most unmodified peptides have very short h… Read more →
Hexarelin: A synthetic hexapeptide that acts as a potent growth hormone secretagogue. Research shows it produces one of the strongest GH release signals among synthetic GHRPs. Also studied for potential cardi… Read more →
HGH Frag 176-191 (HGH Fragment 176-191): A stabilized fragment of human growth hormone spanning amino acids 176–191. Research in animal models focuses on its lipolytic (fat-burning) properties without the IGF-1 elevation associated with f… Read more →
HPLC Testing (High-Performance Liquid Chromatography): The primary analytical method used to determine peptide purity. A dissolved sample is injected into a column packed with stationary-phase material and eluted with a gradient mobile phase. Component… Read more →
Humanin (HN): A 21-amino-acid peptide encoded within the 16S rRNA region of the mitochondrial genome, making it one of the known mitochondria-derived peptides (MDPs). Blood levels decline with age. Research in a… Read more →
Hypothalamic-Pituitary Axis (HPA / HPG Axis): The hierarchical neuroendocrine signaling cascade connecting the hypothalamus, pituitary gland, and peripheral target glands. The growth hormone axis (GHRH → GH → IGF-1) and gonadal axis (GnRH → LH… Read more →

I

IGF-1 (Insulin-Like Growth Factor-1): A 70-amino-acid peptide hormone produced primarily in the liver in response to growth hormone stimulation. The primary mediator of GH's anabolic effects on muscle, bone, and organ tissue. Activates… Read more →
IGF-1 DES (DES(1-3) IGF-1): A truncated form of IGF-1 missing the first three N-terminal amino acids (Gly-Pro-Glu). This modification reduces binding affinity for insulin-like growth factor binding proteins (IGFBPs) by approx… Read more →
IGF-1 LR3 (Insulin-like Growth Factor 1 Long R3): A recombinant analogue of IGF-1 with a 13-amino-acid extension that reduces binding to IGF-binding proteins, extending its half-life. Studied for muscle cell proliferation and differentiation in pr… Read more →
IL-6 (Interleukin-6): A pleiotropic cytokine secreted by T-cells, macrophages, and muscle cells (as a myokine during exercise). Plays dual roles as both pro-inflammatory (in acute phase response) and anti-inflammatory (… Read more →
In Vitro: Latin for "in glass." Research conducted outside a living organism in controlled laboratory conditions, typically in cell cultures, tissue samples, or test tubes. In vitro studies are the first ste… Read more →
In Vivo: Latin for "within the living." Research conducted in intact living organisms, including animal models (rodents, primates) and eventually human clinical trials. In vivo studies capture the full comp… Read more →
Intranasal Administration (IN delivery): Delivery of compounds through the nasal mucosa. Allows some compounds to bypass the blood-brain barrier and reach the CNS directly via the olfactory and trigeminal nerve pathways. Used for Semax an… Read more →
Ipamorelin: A selective growth hormone secretagogue peptide that stimulates GH release with minimal effect on cortisol or prolactin. Often studied alongside CJC-1295 for synergistic GH pulse effects. Read more →

K

KdPT (Lys-Asp-Pro-Thr): A tetrapeptide fragment of IGF-1 corresponding to positions 2–4 of the mature protein (with an additional N-terminal lysine). Studied for its anti-inflammatory effects in intestinal epithelial cell… Read more →
KPV (Lys-Pro-Val): A C-terminal tripeptide fragment of alpha-MSH. Retains the anti-inflammatory activity of the full peptide without melanocortin receptor binding. Research demonstrates inhibition of NF-κB pathway, r… Read more →

L

Liraglutide (Victoza / Saxenda): A GLP-1 receptor agonist with 97% sequence homology to native GLP-1. FDA-approved for type 2 diabetes (Victoza) and obesity (Saxenda). Twice-daily injections replaced by once-weekly semaglutide in … Read more →
LL-37 (LL-37 (Cathelicidin)): The only cathelicidin antimicrobial peptide found in humans. Research covers its roles in innate immunity, wound healing, and modulation of inflammatory responses. Read more →
Lyophilization (Freeze-Drying): A dehydration process that preserves biological materials by first freezing them, then reducing the surrounding pressure to allow frozen water to sublimate directly from solid to vapor. The resulti… Read more →
Lyophilized Powder (Lyophilisate): The freeze-dried solid form of a peptide after lyophilization. Appears as a white or off-white powder or cake in a sealed vial. Must be reconstituted with an appropriate sterile diluent (bacteriost… Read more →

M

Melanotan II: A synthetic analogue of alpha-melanocyte-stimulating hormone (α-MSH). Research has studied its effects on melanogenesis (skin tanning), appetite suppression, and sexual function via melanocortin re… Read more →
MGF (Mechano Growth Factor): A splice variant of IGF-1 produced locally in muscle tissue in response to mechanical stress or damage. Research focuses on its role in activating muscle stem cells (satellite cells) for repair and… Read more →
MK-677 (Ibutamoren): A non-peptide, orally bioavailable growth hormone secretagogue that mimics ghrelin at the GHS-R1a receptor. Unlike peptide GHSs (GHRP-2, Ipamorelin), MK-677 is taken orally and has a half-life of a… Read more →
Modified GRF 1-29 (Mod GRF 1-29 / CJC-1295 without DAC): A GHRH analogue spanning amino acids 1–29 of native GHRH, with four amino acid substitutions to increase potency and resistance to enzymatic degradation. Also referred to as CJC-1295 without DAC. H… Read more →
MOTS-c (Mitochondrial Open Reading Frame of the 12S rRNA-c): A 16-amino-acid mitochondria-derived peptide (MDP) encoded within the 12S rRNA gene of the mitochondrial genome. Research in mice demonstrated that MOTS-c acts as an exercise mimetic, improving ins… Read more →
Mounjaro (Tirzepatide (diabetes brand)): The brand name for tirzepatide (5 mg, 10 mg, 15 mg weekly injection) approved by the FDA in May 2022 for type 2 diabetes management. Manufactured by Eli Lilly. The name derives from "mountain" imag… Read more →
Myostatin (GDF-8): A member of the TGF-β superfamily that acts as a negative regulator of muscle growth. Naturally limits skeletal muscle hypertrophy. Follistatin (both FST-344 and FST-315 isoforms) inhibits myostati… Read more →

N

NAD+ (Nicotinamide Adenine Dinucleotide): A coenzyme present in every living cell, central to cellular energy metabolism, DNA repair, and gene expression regulation via sirtuins. Not a peptide itself, but frequently used alongside peptide … Read more →
Neuropeptide: A peptide that acts as a neurotransmitter, neuromodulator, or neurohormone in the nervous system. Includes substance P, neuropeptide Y (NPY), neurotensin, VIP, oxytocin, and vasopressin. Neuropepti… Read more →
Nitric Oxide (NO): A short-lived gaseous signaling molecule produced from L-arginine by nitric oxide synthase (NOS) enzymes. Regulates vasodilation, platelet aggregation, neurotransmission, and immune cell function. … Read more →
Nootropic Peptide: A peptide with cognitive-enhancing, neuroprotective, or neuroplasticity-promoting properties. Examples include Semax, Selank, Dihexa, P21, and Pinealon. Unlike many stimulant nootropics, peptide no… Read more →

O

Octreotide (Sandostatin): A synthetic somatostatin analogue (8-amino-acid cyclic peptide) that suppresses GH, glucagon, and insulin secretion. FDA-approved for acromegaly, carcinoid tumors, and VIPomas. Used in research as … Read more →
Oxytocin: A 9-amino-acid neuropeptide hormone produced in the hypothalamus and released by the posterior pituitary. Primary physiological roles include uterine contraction during childbirth and milk ejection… Read more →
Ozempic (Semaglutide (diabetes brand)): The brand name for semaglutide 0.5 mg, 1 mg, and 2 mg weekly subcutaneous injection, approved by the FDA for type 2 diabetes management. Manufactured by Novo Nordisk. SUSTAIN clinical trial program… Read more →

P

P21 (P21 Peptide (CNTF-derived)): A short peptide derived from ciliary neurotrophic factor (CNTF) that activates the JAK/STAT3 signaling pathway in the hippocampus. Animal research demonstrated improved working memory, enhanced neu… Read more →
Palmitoyl Pentapeptide-4 (Matrixyl (Pal-KTTKS)): A matrikine peptide formed by lipidating the collagen I fragment KTTKS (Lys-Thr-Thr-Lys-Ser) with palmitic acid. Stimulates fibroblast synthesis of collagen I and III, fibronectin, and hyaluronic a… Read more →
PEG-MGF (Pegylated Mechano Growth Factor): A chemically modified form of MGF (Mechano Growth Factor, a splice variant of IGF-1) in which polyethylene glycol (PEG) chains are attached to the peptide to extend its biological half-life from ap… Read more →
Peptide Bond: The covalent chemical bond formed between the carboxyl group (–COOH) of one amino acid and the amino group (–NH₂) of an adjacent amino acid, releasing a water molecule (condensation reaction). The … Read more →
Peptide Purity: The percentage of the target peptide compound in a sample relative to all other components, measured by HPLC. Research-grade peptides are generally ≥98% pure by HPLC analysis. Common impurities inc… Read more →
Peptide Stability: The degree to which a peptide maintains its chemical integrity and biological activity under specified storage conditions. Lyophilized peptides at –20°C: stable 2–5 years. Reconstituted peptides at… Read more →
Peptides: Short chains of amino acids linked by peptide bonds, typically defined as 2–50 amino acids in length (compared to proteins, which are longer polypeptide chains). Found throughout biology as hormone… Read more →
Pharmacodynamics (PD): The study of the biochemical and physiological effects of a drug on the body, including its mechanism of action, receptor binding, and the relationship between drug concentration and effect. The "w… Read more →
Pharmacokinetics (PK): The study of how the body processes a drug, encompassing Absorption, Distribution, Metabolism, and Excretion (ADME). The "what the body does to the drug." Key PK parameters for peptides include hal… Read more →
Pinealon (Glu-Asp-Arg): A synthetic tripeptide developed from brain and pineal gland tissue extracts at the St. Petersburg Institute of Bioregulation and Gerontology. Animal research has investigated its neuroprotective p… Read more →
Pituitary Gland (Hypophysis): A pea-sized endocrine gland located at the base of the brain, connected to the hypothalamus by the pituitary stalk. The anterior pituitary produces growth hormone (GH), TSH, FSH, LH, ACTH, and prol… Read more →
POMC (Pro-Opiomelanocortin): A large precursor polypeptide produced in the anterior pituitary, hypothalamus, and skin. Post-translational cleavage of POMC produces multiple bioactive peptides including ACTH, α-MSH, β-MSH, β-en… Read more →
PT-141 (PT-141 (Bremelanotide)): A melanocortin receptor agonist (MC3R and MC4R) studied for its effects on sexual function. Unlike PDE5 inhibitors, it acts centrally via the nervous system rather than on vascular tissue. Read more →

R

Receptor Agonist: A compound that binds to a specific receptor and activates it, mimicking or exceeding the effect of the endogenous ligand. Most research peptides function as receptor agonists — for example, Ipamor… Read more →
Receptor Antagonist: A compound that binds to a receptor and blocks activation without producing a biological response itself. Used in research to confirm receptor-mediated mechanisms and understand peptide pharmacolog… Read more →
Reconstitution: The process of dissolving lyophilized peptide powder in a sterile diluent. Standard procedure involves injecting bacteriostatic water (or sterile water for single use) slowly along the side of the … Read more →
Research Peptides: Synthetic peptides manufactured for scientific investigation and preclinical study, sold legally as research chemicals rather than approved drugs. Include compounds such as BPC-157, TB-500, CJC-129… Read more →
Reta (Retatrutide (informal)): Informal abbreviation for retatrutide, the triple incretin receptor agonist (GLP-1/GIP/glucagon) under Phase 3 clinical investigation by Eli Lilly. Widely used in obesity research communities, onli… Read more →
Retatrutide (LY3437943): A triple receptor agonist peptide (GLP-1 receptor + GIP receptor + glucagon receptor) in Phase 3 clinical development by Eli Lilly (internal code LY3437943). Phase 2 SURMOUNT-J trials reported aver… Read more →
Route of Administration (ROA): The path by which a compound enters the body. Research peptides are most commonly administered via subcutaneous injection (SC), intramuscular injection (IM), or intranasal spray (IN). Oral administ… Read more →

S

Secretagogue: A substance that stimulates the secretion of another substance. In peptide research, the term is most commonly used to describe growth hormone secretagogues (GHSs), which stimulate pituitary secret… Read more →
Selank: A synthetic analogue of the human tetrapeptide tuftsin with added stabilizing sequence. Russian-developed peptide studied for anxiolytic and nootropic effects. Has been studied in human clinical tr… Read more →
Semaglutide (Ozempic / Wegovy / Rybelsus): A GLP-1 receptor agonist with 94% sequence homology to native GLP-1, modified with a C18 fatty diacid chain for albumin binding. Half-life of approximately 7 days enables once-weekly injection. FDA… Read more →
Semax: A heptapeptide derived from the ACTH sequence, developed in Russia. Research focuses on neuroprotective, nootropic, and anxiolytic properties. Used clinically in Russia for stroke and cognitive con… Read more →
Sermorelin (Sermorelin (GHRH 1-29)): A synthetic analogue of the first 29 amino acids of endogenous GHRH. Stimulates the pituitary to produce and secrete growth hormone. Used clinically as a diagnostic agent and in some anti-aging pro… Read more →
SNAP-8 (Acetyl Octapeptide-3): A synthetic octapeptide that mimics the N-terminal segment of SNAP-25, a component of the SNARE complex involved in neurotransmitter vesicle docking at the neuromuscular junction. Studied in cosmet… Read more →
Somatostatin (SRIF / GH-inhibiting hormone): A 14-amino-acid (and 28-AA extended form) cyclic peptide produced in the hypothalamus, pancreas, and gastrointestinal tract. Inhibits GH, TSH, insulin, glucagon, and gastrin secretion. Acts as the … Read more →
SS-31 (Szeto-Schiller Peptide 31 (Elamipretide)): A mitochondria-targeted aromatic-cationic tetrapeptide (D-Arg-2′6′Dmt-Lys-Phe-NH₂) developed by Hazel Szeto and Peter Schiller. Selectively concentrates ~1000-fold in the inner mitochondrial membra… Read more →
Sterile Water for Injection (SWFI): Highly purified, pyrogen-free water that has been sterilized but contains no additives or preservatives. Used as a single-use diluent for peptide reconstitution. Because it contains no bacteriostat… Read more →
Subcutaneous Injection (SC / SQ injection): Injection into the subcutaneous tissue layer between the skin dermis and the underlying muscle fascia, using a short (typically 4–6 mm) insulin-type needle at a 45–90° angle. The most common route … Read more →

T

TB-500 (Thymosin Beta-4 (TB-500)): A synthetic version of Thymosin Beta-4, a naturally occurring 43-amino-acid peptide found in virtually all human cells. Research focuses on its actin-binding properties, systemic tissue repair effe… Read more →
Telomere: Repetitive nucleotide sequences (TTAGGG in humans) capping the ends of chromosomes, protecting them from degradation and end-to-end fusion. Telomeres shorten by approximately 30–200 base pairs with… Read more →
Tesamorelin: A stabilized GHRH analogue approved by the FDA for HIV-associated lipodystrophy. One of the few research peptides with clinical approval. Research also covers visceral fat reduction and cognitive e… Read more →
Thymalin (Thymus peptide complex): A polypeptide complex extracted from bovine thymus glands, developed at the St. Petersburg Institute of Bioregulation and Gerontology. Contains a mixture of thymic peptides including thymopoietin f… Read more →
Thymosin Alpha-1 (Tα1 / Thymalfasin): A 28-amino-acid peptide originally isolated from the thymus gland. FDA-approved in over 35 countries for chronic hepatitis B and C, and as an immune adjuvant. Activates dendritic cells, T-cells, an… Read more →
Tirz (Tirzepatide (informal)): Informal abbreviation widely used for tirzepatide, the dual GLP-1/GIP receptor agonist marketed as Mounjaro (type 2 diabetes) and Zepbound (obesity). Used extensively in online research communities… Read more →
Tirzepatide (Mounjaro / Zepbound): A dual GIP (glucose-dependent insulinotropic polypeptide) and GLP-1 receptor agonist — the first in its class. FDA-approved for type 2 diabetes (Mounjaro) and obesity (Zepbound). Clinical trials (S… Read more →
Triple Agonist (GLP-1/GIP/Glucagon Receptor Agonist): A compound class that simultaneously activates three metabolic hormone receptors: the GLP-1 receptor, GIP receptor, and glucagon receptor. Retatrutide (LY3437943) by Eli Lilly is the lead Phase 3 c… Read more →
Triptorelin (Decapeptyl / Trelstar): A synthetic GnRH agonist decapeptide. Used clinically for prostate cancer, endometriosis, uterine fibroids, and central precocious puberty. Short-term use transiently elevates LH and testosterone; … Read more →

V

Vasopressin (ADH / Arginine Vasopressin (AVP)): A 9-amino-acid neuropeptide hormone synthesized in the hypothalamus. Primary functions include increasing water reabsorption in the kidneys (antidiuretic effect) and vasoconstriction. Also acts as … Read more →
Vilon (Lys-Glu): A synthetic dipeptide (Lys-Glu) developed from thymus gland extracts as part of the Russian bioregulatory peptide research program. Studied for immune system enhancement, anti-aging effects, and po… Read more →
VIP (Vasoactive Intestinal Peptide): A 28-amino-acid neuropeptide found in the nervous system and gut. Functions as a potent vasodilator and smooth muscle relaxant. Regulates circadian rhythms via the suprachiasmatic nucleus (SCN). St… Read more →

W

Water for Injection (WFI): Highly purified, sterile, pyrogen-free water meeting pharmacopeial standards (USP, EP). The reference standard for pharmaceutical-grade water used in drug manufacturing and injection preparation. W… Read more →
Wegovy (Semaglutide 2.4 mg (obesity brand)): The brand name for semaglutide 2.4 mg weekly subcutaneous injection, approved by the FDA in June 2021 for chronic weight management in adults with obesity (BMI ≥30) or overweight (BMI ≥27) with at … Read more →

Z

Zepbound (Tirzepatide (obesity brand)): The brand name for tirzepatide (5 mg, 10 mg, 15 mg weekly injection) approved by the FDA in November 2023 for chronic weight management in adults with obesity or overweight with a weight-related co… Read more →