Peptide Glossary — 132+ Terms

A pre-mixed vial containing two peptides (like Tesamorelin and Ipamorelin) designed to work together for better results, such as fat loss and muscle building. Blends make dosing easier by combining effects.

Similar to a 2X blend but with three peptides (e.g., Tesamoralin, Ipamorelin, and MGF), often for advanced goals like athletic recovery, anti-aging, and adding lean muscle.

A blend of four peptides (e.g., Tesamoralin, Ipamorelin, GHRP-2, and MGF) aimed at bulking, increasing muscle mass, and boosting appetite.

A 13-amino acid peptide hormone derived from POMC (pro-opiomelanocortin) that acts on melanocortin receptors throughout the body. Its primary roles include regulation of skin pigmentation via MC1R, appetite suppression and energy expenditure via MC4R in the hypothalamus, and anti-inflammatory signaling via MC1R and MC3R in immune cells. KPV is a tripeptide fragment (amino acids 11-13) of alpha-MSH that retains the anti-inflammatory melanocortin receptor binding activity of the full-length hormone while being small enough to cross biological barriers. Melanotan I and II in the Peptide Hub database are synthetic alpha-MSH analogues that act on melanocortin receptors for tanning and libido research applications.

The basic building blocks that link together to form peptides and proteins. There are 20 common ones in the body, each with a unique side chain that gives it special properties.

The body's master metabolic switch, activated by low energy states (like exercise or fasting). AMPK triggers glucose uptake, fat burning, and mitochondrial biogenesis. Several mitochondrial peptides like MOTS-c activate AMPK to mimic the metabolic effects of exercise at the cellular level.

The formation of new blood vessels from existing ones. Critical to tissue healing because new vessels deliver oxygen and nutrients to damaged tissue. Several healing peptides including BPC-157 and TB-500 promote angiogenesis as a central mechanism of action.

A property that helps break down or prevent sticky layers (biofilms) formed by bacteria, making infections harder to treat.

Something that kills or stops the growth of microbes like bacteria, viruses, or fungi, acting like a natural antibiotic.

A synthetic peptide derived from human growth hormone that helps break down fat (lipolysis) without affecting hunger or blood sugar levels. Often used for weight management and stacked with other peptides.

A non-hematopoietic erythropoietin (EPO) analogue engineered to remove EPO's blood cell-stimulating activity while preserving its tissue-protective signaling through the innate repair receptor (IRR). ARA-290 binds the IRR — a heterodimer of the EPO receptor (EPOR) and the common beta receptor (CD131) — expressed on immune cells, neurons, and injured tissues. This activation triggers anti-inflammatory and regenerative signaling pathways without the thromboembolic risks of full EPO. ARA-290 has received FDA Fast-Track designation for autoimmune small fiber neuropathy (SFN) following Phase 2b clinical trials demonstrating improvement in corneal nerve fiber density and symptom scores. It is studied in the MCAS Protocol Stack alongside VIP, KPV, and TA-1. For research and educational purposes only.

Short for Bacteriostatic Water, a sterile water mixed with a small amount of benzyl alcohol to prevent bacterial growth. It's used to dissolve (reconstitute) peptide powders for safe injection.

Brain-Derived Neurotrophic Factor - A protein that supports the growth and survival of brain cells (neurogenesis), helping with memory, learning, mood, and cognitive function. Used in peptides for brain health and repair.

The proportion of a substance that enters circulation when introduced into the body and is able to have an active effect at the target site.

A class of short peptides (typically 2-4 amino acids) developed primarily by Russian researchers, notably Professor Vladimir Khavinsky, that are designed to restore and normalize the function of specific organs and tissues. Bioregulators include Epithalon (pineal gland and telomeres), Pinealon (brain cortex), Thymalin (thymus and immune), and Cortagen (brain). They work by penetrating cell nuclei and directly influencing gene expression.

A synthetic peptide known for its healing properties; it protects and repairs tissues like muscles, gut, heart, and nerves. Popular for injury recovery, reducing inflammation, and overall protection (neuroprotective, gastroprotective, etc.).

A gut-restricted, orally bioavailable small molecule peptide ligand developed by Landos Biopharma that selectively activates the LANCL2 signaling pathway in intestinal immune cells. BT-11 is specifically engineered to remain in the gut lumen without systemic absorption — targeting IBD (inflammatory bowel disease), Crohn's disease, and ulcerative colitis through a localized immune regulatory mechanism. By activating LANCL2, BT-11 promotes anti-inflammatory cytokine balance in intestinal immune cells. Phase 2 clinical trials for Crohn's disease showed favorable safety and preliminary efficacy. BT-11 pairs well with Larazotide (tight junction repair) and KPV (mucosal anti-inflammation) in gut healing protocols.

A peptide that controls appetite, supports weight loss, and improves metabolism. Often added to GLP-1 peptides to enhance effects and reduce doses.

A phospholipid found exclusively in the inner mitochondrial membrane that holds the electron transport chain machinery in place. Cardiolipin degrades with age and oxidative stress, reducing energy production efficiency. SS-31 works by binding and stabilizing cardiolipin.

Describes something that protects the heart from damage, like reducing inflammation or improving blood flow.

Your body's internal 24-hour rhythm that controls sleep, hormones, and other functions; disrupting it can affect health.

A growth hormone-releasing hormone (GHRH) peptide that boosts your body's natural growth hormone and IGF-1 levels for muscle growth, fat loss, and anti-aging. 'No DAC' means it's short-acting without a prolonging modification.

Similar to the no-DAC version but with a Drug Affinity Complex (DAC) that makes it last longer in the body, allowing less frequent dosing.

A synthetic tripeptide bioregulator (EDR: Glutamic acid-Aspartic acid-Arginine) developed by Professor Vladimir Khavinsky at the St. Petersburg Institute of Bioregulation and Gerontology, specifically targeting brain cortex neuroprotection and cognitive aging. Structurally related to Pinealon (also an EDR-sequence peptide), Cortagen is formulated for cortical cell protection rather than hippocampal-pineal regulation. It works through epigenetic gene regulation of neuronal survival and growth factor expression in the cerebral cortex. Classified as a geroprotector — a compound designed to slow age-related biological decline in cortical function. Part of the expanded Khavinsky neuroprotective protocol alongside Pinealon (hippocampal memory), Epithalon (telomere-pineal axis), and Thymalin (immune aging). Available as oral tablets. For research and educational purposes only.

A natural compound from turmeric used here as an injectable for reducing inflammation, acting as an antioxidant, and supporting tissue repair and gut health.

The active metabolite of Noopept (omberacetam) after oral administration. An endogenous dipeptide found naturally in the brain that acts as a positive modulator of AMPA receptors and activates the BDNF/TrkB signaling pathway, driving Noopept's nootropic and neuroprotective effects.

Drug Affinity Complex - A chemical modification added to some peptides (like CJC-1295) to make them stay active in the body longer, reducing how often you need to inject.

A 39-amino acid dual GLP-1/GIP receptor agonist in the Regulator Series (also called Dual Regulator). Features a C20 fatty diacid side chain and dual incretin receptor activation. Structurally analogous in class to tirzepatide. CAS: 2023788-19-2.

Delta Sleep-Inducing Peptide - A peptide that helps reset your sleep cycle, supports the nervous and hormonal systems, and aids in detox or withdrawal from substances like alcohol or opioids.

Common name for DIA-39-C20 — a dual GLP-1/GIP receptor agonist with a C20 fatty diacid chain. Part of the Peptide Receptor Modulator Research Series. Activates both GLP-1R and GIPR simultaneously for synergistic metabolic effects beyond single agonism.

Something produced naturally inside your body, like endogenous growth hormone (made by your pituitary gland) versus exogenous (injected from outside).

A synthetic peptide that works on the pineal gland to lengthen telomeres (DNA caps), restore melatonin levels, and promote anti-aging effects.

Extracellular signal-regulated kinase 1/2 — a cellular signaling pathway that drives cell proliferation, migration, and survival. BPC-157 activates ERK1/2 in endothelial cells to promote wound healing and vascular tube formation.

A state where you haven't eaten for a while (e.g., 45 minutes before/after injection), often recommended to maximize peptide absorption or effects.

A peptide that blocks myostatin (a protein that limits muscle growth), helping increase muscle mass, strength, and treat muscle wasting; also reduces cortisol.

A D-retro-inverso (DRI) peptide designed to selectively induce apoptosis in senescent cells — cells that have permanently stopped dividing but remain metabolically active, secreting pro-inflammatory SASP compounds. FOXO4-DRI works by blocking the interaction between FOXO4 (a transcription factor that promotes senescent cell survival) and p53 (a tumor suppressor), disrupting the pro-survival signal that keeps senescent cells alive. The landmark 2017 Nature paper by Baar et al. demonstrated significant rejuvenation in aged mice. A 2025 Nature Communications study confirmed the mechanism at atomic resolution. FOXO4-DRI is the most researched peptide senolytic available, studied alongside small molecule senolytics as a tool for senescent cell clearance research. The DRI modification uses D-amino acids in reversed sequence, creating enzymatic resistance for extended activity. For research and educational purposes only.

The process by which a molecule binds to monomeric (free) actin, keeping it available for rapid cytoskeletal assembly when cells need to move or change shape. TB-500's primary mechanism — it sequesters G-actin to enable faster cellular migration into injury sites.

Protects the stomach and digestive system from damage or inflammation.

A compound classified by Russian gerontology researchers as capable of slowing biological aging of a specific organ or system. Distinguished from general anti-aging supplements by its targeted, organ-specific mechanism. Examples include Epithalon (pineal gland and telomeres), Pinealon (brain cortex), and Thymalin (thymus and immune aging).

A copper-bound peptide that tightens skin, reduces wrinkles, fights hair loss, aids wound healing, bone repair, and reduces inflammation.

A hormone made in the stomach that signals hunger to the brain; some peptides affect it to increase appetite.

A growth hormone-releasing peptide (second strongest) that boosts natural GH and ghrelin for muscle growth; increases appetite slightly.

Similar to GHRP-2 but third strongest, with stronger appetite stimulation for bulking.

An incretin hormone that, alongside GLP-1, regulates insulin release after meals. GIP receptors are found in the brain, fat cells, and pancreas. Dual GLP-1/GIP agonists produce synergistic weight loss because the pathways converge on overlapping cellular machinery.

A mix of GHK-Cu, BPC-157, and TB-500 for enhancing skin health, accelerating healing, and supporting tissue regeneration.

Glucagon-Like Peptide-1 - A hormone mimic that enhances insulin, lowers blood sugar, suppresses appetite, and promotes weight loss (up to 15%); may cause nausea.

Targets two receptors (GLP-1 and GIP) for better weight loss (up to 20%), slower digestion, and less nausea; similar to drugs like Tirzepatide.

An informal community term for triple GLP-1/GIP/glucagon receptor agonists -- specifically Retatrutide (LY3437943) by Eli Lilly. The "GLP-3" designation is not an official pharmacological classification but reflects the compound's position as a third-generation evolution: GLP-1 mono-agonists (semaglutide, "first gen") produce ~15% weight loss; GLP-1/GIP dual agonists (tirzepatide, "second gen") produce ~21%; GLP-3 triple agonists (Retatrutide) have shown 26-29% weight loss in Phase 3 with no plateau. The glucagon receptor component is the key differentiator -- it uniquely increases resting metabolic rate and hepatic fat oxidation. Also called "Reta" or "GLP-3 R". See: Retatrutide.

A G-protein coupled receptor that binds glucagon, a hormone produced by pancreatic alpha cells. In the liver, GCGR activation promotes glycogenolysis and gluconeogenesis. In adipose and skeletal tissue, GCGR activation increases lipolysis and resting metabolic rate -- the energy expenditure mechanism that Retatrutide (GLP-3) adds on top of GLP-1 and GIP receptor agonism. At the doses used in triple agonists, the glucagon-driven blood glucose rise is buffered by concurrent GLP-1/GIP insulin sensitization, leaving a net increase in fat oxidation and metabolic rate. This is what distinguishes triple agonists from dual agonists in terms of weight loss magnitude.

A peptide that stimulates the release of hormones (LH and FSH) to boost testosterone production and treat low hormone levels (hypogonadism).

The G protein-coupled receptor for kisspeptin, expressed on GnRH neurons in the hypothalamus. Also called KISS1R. Loss-of-function mutations in GPR54 cause idiopathic hypogonadotropic hypogonadism — failure to enter puberty — establishing it as essential for reproductive axis activation. Binding of kisspeptin to GPR54 triggers calcium mobilization and synchronous GnRH pulse release.

The time required for the concentration of a substance to decrease to half of its initial value, important for determining dosing frequency in research.

Human Chorionic Gonadotropin - A hormone used to stimulate testosterone and sperm in men or ovulation in women; treats hypogonadism and supports fertility.

The most potent growth hormone-releasing peptide that boosts GH without increasing appetite; promotes muscle growth.

Human Growth Hormone - The actual growth hormone injected directly (exogenous) to build muscle, increase bone density, and promote fat breakdown.

A transcription factor activated under low-oxygen or cellular stress conditions that regulates up to 100 genes involved in neuroprotection, angiogenesis, glucose transport, and mitochondrial function. Activated by Noopept (omberacetam) as part of its neuroprotective mechanism.

The hypothalamic-pituitary-gonadal axis — the hierarchical hormonal signaling cascade governing sex hormone production. The hypothalamus releases GnRH → the pituitary releases LH and FSH → the gonads (testes or ovaries) produce testosterone or estrogen. Kisspeptin neurons in the arcuate nucleus are the primary upstream regulators of this axis, controlling GnRH pulse frequency and amplitude.

A 21-amino acid mitochondrial-derived peptide discovered in 2001 in surviving brain cells of an Alzheimer's patient. Works primarily by blocking pro-apoptotic proteins (particularly Bax), protecting cells from stress-induced programmed death. Forms the third component of the mitochondrial peptide trio alongside MOTS-c and SS-31.

A condition where the body doesn't produce enough sex hormones like testosterone, leading to low energy, fertility issues, etc.

Insulin-Like Growth Factor-1 - A hormone stimulated by GH that helps build muscle, burn fat, and repair tissues.

A short-acting variant of IGF-1 for similar muscle and fat effects.

A long-acting form of IGF-1 that binds to receptors to build muscle, boost metabolism, and aid recovery.

A term coined by immunologist Claudio Franceschi describing the chronic, low-grade, systemic inflammatory state that progressively increases with age — a central driver of multiple age-related diseases including cardiovascular disease, type 2 diabetes, Alzheimer's disease, sarcopenia, and cancer. Inflammaging arises from converging mechanisms: accumulation of senescent cells secreting pro-inflammatory SASP compounds, declining autophagy and cellular clearance, gut microbiome dysbiosis, mitochondrial dysfunction generating reactive oxygen species, and progressive immune dysregulation (immunosenescence). It is mechanistically distinct from acute inflammation — it is sterile (no pathogen trigger), chronic, and subclinical. Research peptides studied in the context of reducing inflammaging include Epithalon (telomere maintenance), FOXO4-DRI (senescent cell clearance), MOTS-c (mitochondrial AMPK activation), and Thymalin (immune aging normalization).

Small proteins released during inflammation that can cause pain or damage if overproduced; some peptides reduce them.

An injection method where the needle goes into a muscle for faster absorption.

A growth hormone-releasing peptide that boosts GH without increasing appetite, cortisol, or prolactin; great for muscle growth.

The master upstream regulator of the HPG axis. Kisspeptin (KP-10) activates GPR54 receptors on GnRH neurons, triggering the LH/FSH/testosterone cascade. A single SubQ injection produces a measurable LH surge within 20–60 minutes and testosterone increases within 2 hours. Studied for hypogonadotropic hypogonadism and limbic sexual processing. See also: GPR54 (KISS1R), HPG Axis, Kisspeptin-10 (KP-10), Metastin.

The C-terminal decapeptide fragment of kisspeptin, comprising the final 10 amino acids of the KISS1 gene product. KP-10 is the most potent and most studied research form — it retains full GPR54 receptor binding and biological activity in a more compact, stable structure than longer kisspeptin isoforms (KP-13, KP-14, KP-54). Standard research vials contain kisspeptin in its KP-10 form.

A four-peptide regenerative research blend combining GHK-Cu (50mg), KPV (10mg), BPC-157 (10mg), and TB-500 (10mg) in a single 80mg vial. KLOW is an evolution of the Glow Blend — it retains the three-compound Glow trio (GHK-Cu, BPC-157, TB-500) and adds KPV as a fourth component for melanocortin receptor-mediated anti-inflammatory and mucosal barrier signaling. The name KLOW is derived from its four components: K (KPV), L (reflecting its regenerative lineage from the Glow stack), O, and W. It is reconstituted with 3ml bacteriostatic water, producing approximately 26.7mg/ml total blend concentration. See the KLOW Blend database entry and The Journal article for full research profile and protocol.

KPV (lysine-proline-valine) is a tripeptide derived from the C-terminal sequence of alpha-MSH (alpha-melanocyte stimulating hormone). It binds melanocortin receptors — primarily MC1R and MC3R — to produce targeted anti-inflammatory effects including suppression of NF-kB pathway activation, reduction of pro-inflammatory cytokines (IL-6, TNF-alpha, IL-1beta), and promotion of intestinal epithelial cell migration for mucosal barrier repair. KPV is studied for inflammatory bowel disease, skin inflammation, wound healing, and gut barrier restoration. It is the differentiating addition in the KLOW Blend — the mechanism that separates KLOW from the Glow Blend (which contains GHK-Cu, BPC-157, and TB-500 but not KPV).

A synthetic 8-amino acid peptide derived from Vibrio cholerae zona occludens toxin (ZOT) that acts as a tight junction regulator in the intestinal epithelium. Larazotide works by blocking the action of zonulin — the endogenous protein that triggers tight junction disassembly and increases intestinal permeability. Unlike compounds that repair existing damage, Larazotide acts preventively and acutely at the barrier level, competitively inhibiting zonulin receptor binding. Phase 2 clinical trials demonstrated significant reduction in intestinal permeability markers in celiac disease and IBD patients. Larazotide is the most specific peptide tool available for tight junction research and is the structural component of the Gut Healing Stack, where it works alongside KPV (mucosal anti-inflammation) and BPC-157 (tissue repair) to address three complementary gut dysfunction mechanisms. Administered orally 30 minutes before meals. For research and educational purposes only.

The process of breaking down fats in the body to release energy.

An antimicrobial peptide that fights bacteria, viruses, and biofilms; used as a natural antibiotic for lung or gut infections.

Freeze-drying process used to preserve peptides by removing water content, extending shelf life and maintaining stability.

An alternative splice variant of the IGF-1 gene produced locally in skeletal muscle in response to mechanical overload and injury. Acts as a local first-responder to activate muscle satellite cells for repair. Has a very short half-life of 5-7 minutes in its native form — see PEG-MGF for a longer-acting version.

A family of five G-protein coupled receptors (MC1R through MC5R) that bind melanocortin peptides including alpha-MSH and its derivatives. Melanocortin receptors are found in the skin, brain, adrenal glands, and immune cells. MC1R and MC3R binding by KPV (a tripeptide fragment of alpha-MSH) produces anti-inflammatory effects through suppression of NF-kB signaling and pro-inflammatory cytokine production. MC1R activation in skin also regulates pigmentation and UV response. Melanocortin receptor agonism is distinct from the mechanisms of other anti-inflammatory compounds on this site — it does not work through GLP receptor pathways, GABA modulation, or cytokine-specific antibodies, but through direct receptor-mediated intracellular signaling in immune and epithelial cells.

The body's production of melanin, the pigment that darkens skin (tanning).

A peptide for inducing tanning and suppressing appetite, with added sexual stimulus.

Similar to MT-I, promotes tanning, appetite suppression, and enhanced libido.

The original name for Kisspeptin-54 (the 54-amino acid isoform), derived from its initial identification as a metastasis suppressor encoded by the KISS1 gene. The name “kisspeptin” came from Hershey, Pennsylvania (where the KISS1 gene was discovered). In research literature, “metastin” and “kisspeptin-54” are used interchangeably; “KP-10” or “kisspeptin” without a number suffix typically refers to the decapeptide research form.

Mechano Growth Factor - A peptide that promotes muscle regeneration and repair after exercise or injury by activating stem cells.

The process by which cells make new mitochondria in response to energy demand or stress. Activated by AMPK and PGC-1α signaling. MOTS-c promotes mitochondrial biogenesis as a core anti-aging and metabolic adaptation mechanism.

The process by which cell 'powerhouses' (mitochondria) produce energy (ATP) from nutrients.

A class of small peptides encoded within mitochondrial DNA rather than nuclear DNA. MDPs represent a newly recognized signaling system through which mitochondria communicate their metabolic state to the rest of the cell and body. Known members include MOTS-c, Humanin, and the SHLP family. Levels of most MDPs decline with age and metabolic disease.

A mitochondrial peptide called 'exercise in a bottle' that turns glucose into energy, aids anti-aging, and helps with diabetes or insulin resistance.

Protects muscles, bones, and joints from damage or inflammation.

A protein that naturally limits muscle growth; inhibiting it allows for more muscle development.

Nicotinamide Adenine Dinucleotide - A molecule essential for cell energy, DNA repair, and mitochondrial function; used for anti-aging and restoring damage.

The growth and development of new brain cells or neurons.

Peptides that function as neurotransmitters or neuromodulators in the nervous system, influencing neural signaling and brain function.

The brain's ability to reorganize and form new connections, helping with learning and adaptation.

Protects brain cells from damage or degeneration.

Known as the 'love hormone,' it boosts social bonding, emotional well-being, and reduces stress/anxiety.

A tetrapeptide (DAVP sequence) derived from the C-terminal region of CNTF (Ciliary Neurotrophic Factor) that stimulates hippocampal neurogenesis — new neuron formation in the brain's memory center — without triggering CNTF's adverse off-target effects including weight loss, inflammation, and broad systemic toxicity. P21 crosses the blood-brain barrier and promotes BDNF expression, reduces tau phosphorylation (a marker of Alzheimer's pathology), and has demonstrated increased brain volume in Alzheimer's disease animal models. In a head-to-head preclinical comparison, P21 outperformed Cerebrolysin on neurogenesis and cognitive outcome measures. P21 is classified in the BRAIN + REPAIR category — working on structural regeneration rather than acute mood modulation. Complementary to Semax (BDNF pathway), Dihexa (synaptogenesis), and PE-22-28 (mood-stabilizing neuroprotection). For research and educational purposes only.

A peptide for neuroprotection, cognitive support, and mood enhancement.

The chemical process of attaching polyethylene glycol (PEG) molecules to a peptide or protein, which extends its half-life by protecting it from enzymatic breakdown and improves bioavailability. Used to create PEG-MGF from native MGF, extending its half-life from minutes to hours or days.

A short chain of 2-50 amino acids linked together; smaller than proteins but can act like hormones or signals in the body for various effects.

The chemical link between amino acids in a peptide or protein, formed by removing water.

A large molecule made of 50+ amino acids; peptides are shorter versions that can turn into or mimic parts of proteins.

A peptide that signals the brain to increase blood flow, arousal, and libido in men and women.

The process of mixing lyophilized (freeze-dried) peptide powder with bacteriostatic water or sterile solution to create an injectable form.

A research peptide classification covering single, dual, and triple incretin receptor agonists: SIA-31-C18 (Single Regulator / GLP-1R only), DIA-39-C20 (Dual Regulator / GLP-1R + GIPR), and TIA-39-C20 (Triple Regulator / GLP-1R + GIPR + GCGR). Each uses a fatty acid side chain for extended half-life.

A synthetic 39-amino acid triple receptor agonist developed by Eli Lilly (LY3437943) that simultaneously activates GLP-1, GIP, and glucagon receptors. Informally called "Reta", "Ret", or "GLP-3" in research and biohacking communities. Phase 3 TRIUMPH-4 trial demonstrated 26-29% mean weight loss over 48-68 weeks -- the highest ever recorded in a pharmaceutical obesity trial -- with no plateau observed at trial end. The glucagon receptor component uniquely adds resting metabolic rate increase and hepatic fat oxidation on top of appetite suppression. GI tolerability comparable to tirzepatide. Also carries COA documentation as "GLP-3 R" in some research supply catalogs. NDA not submitted as of May 2026. Research compound only. See: GLP-3, Glucagon receptor (GCGR).

The collection of pro-inflammatory cytokines, chemokines, growth factors, and matrix metalloproteinases that senescent cells actively secrete into their surrounding tissue. SASP includes IL-6, IL-8, IL-1beta, TNF-alpha, MMP-3, MMP-9, and dozens of other signaling molecules that collectively create a chronic local inflammatory environment. Initially, SASP serves a useful purpose — alerting the immune system to clear the senescent cell. When the immune system fails to clear senescent cells efficiently (as occurs with age), SASP becomes chronic and drives tissue dysfunction, accelerates aging in surrounding cells (paracrine senescence), and contributes to systemic inflammaging. SASP is the primary reason senescent cell accumulation is harmful with aging. Senolytic peptides like FOXO4-DRI are studied as tools to eliminate senescent cells and thereby reduce SASP signaling.

Muscle stem cells that reside between the muscle fiber membrane and its surrounding sheath. In a quiescent resting state under normal conditions, they activate rapidly after mechanical stress or injury. When activated by signals like MGF, they proliferate and differentiate into new muscle fibers, driving repair and hypertrophy.

An anti-anxiety peptide that boosts serotonin and dopamine for better mood, learning, and memory.

A peptide that triggers brain-derived neurotrophic factor for improved neuroplasticity, learning, and blood flow to the brain.

A cell that has permanently exited the cell cycle in response to DNA damage, telomere shortening, oxidative stress, or oncogenic signals — but remains metabolically active rather than undergoing apoptosis. Senescent cells accumulate in tissues with aging and are identified by markers including p16 and p21 expression, senescence-associated beta-galactosidase activity, and SASP secretion. A small number serve beneficial roles in wound healing and tumor suppression. However, the progressive accumulation of senescent cells with age — driven by declining immune clearance — creates a pro-inflammatory, pro-degenerative tissue environment. Selective removal of senescent cells is the focus of the senolytic research field, of which FOXO4-DRI is the most studied peptide tool.

A compound that selectively induces apoptosis in senescent cells while leaving healthy cells intact. Senolytics exploit the upregulated survival pathways that senescent cells depend on — pro-survival BCL-2 family proteins, FOXO4-p53 interactions — as selective targets. Classes include: BCL-2/BCL-XL inhibitors (navitoclax), tyrosine kinase inhibitors (dasatinib), flavonoids (quercetin), and peptide senolytics (FOXO4-DRI). The complementary term 'senomorphic' describes compounds that reduce SASP secretion without killing senescent cells. FOXO4-DRI is the primary research-grade peptide senolytic — it works by disrupting the FOXO4-p53 anti-apoptotic interaction specifically upregulated in senescent cells. For research and educational purposes only.

A growth hormone-releasing hormone that boosts natural GH for muscle strength, repair, anti-aging, and bone density.

A family of six mitochondria-encoded peptides (SHLP1 through SHLP6) discovered in 2016 by researchers at USC, all encoded within the 12S ribosomal RNA region of the mitochondrial genome — the same gene region that encodes Humanin. SHLPs share structural similarities with Humanin but exert distinct biological functions. SHLP2 demonstrates cytoprotective effects similar to Humanin along with unique anabolic signaling — regulating IGF-1 and insulin sensitivity pathways, with levels that decline with age. SHLP6 has a unique dual profile: cytoprotective in normal cells but pro-apoptotic in cancer cell lines, a property not shared by other MDPs. SHLPs complete the known family of mitochondrial-derived peptides (MDPs) alongside Humanin and MOTS-c, forming the comprehensive mitochondrial encoded peptidome. Research on SHLPs is earlier-stage than Humanin or MOTS-c but rapidly expanding.

A 31-amino acid single GLP-1 receptor agonist in the Regulator Series (also called Single Regulator). Features a C18 fatty diacid side chain for extended half-life via albumin binding. Structurally analogous in class to semaglutide. CAS: 910463-68-2.

Common name for SIA-31-C18 — a GLP-1 receptor agonist with a C18 fatty diacid chain. Part of the Peptide Receptor Modulator Research Series. Activates GLP-1R only, making it the simplest member of the Regulator Series hierarchy.

A family of proteins that regulate cellular aging, DNA repair, inflammation, and metabolic efficiency. Sirtuins require NAD+ as their substrate. When NAD+ levels decline with age, sirtuin activity drops — one reason direct NAD+ supplementation is linked to longevity research.

An oral peptide (tablets) for muscle or metabolic support, though details are limited in the guide.

A peptide that targets mitochondria to protect and restore energy production, boosting ATP, brain power, and fighting cancer.

An injection under the skin into fatty tissue for slow, steady absorption.

A dual agonist peptide targeting GLP-1 and glucagon for appetite reduction, weight loss, and help with fatigue or fatty liver.

The formation of new synaptic connections between neurons. Critical for learning, memory formation, and recovery from brain injury. Stimulated by BDNF, Semax, and — according to early research now partially retracted — Dihexa via the HGF/c-Met pathway.

Delivery method where a substance enters the bloodstream to affect the entire body, as opposed to local or targeted delivery.

Thymosin Alpha-1 - A peptide that stimulates the immune system by activating T-cells and other cells to fight bacteria, viruses, fungi, and cancer.

A peptide that reduces inflammation and speeds wound healing in joints and muscles by binding to actin.

An enzyme that adds DNA sequences to the ends of chromosomes (telomeres), slowing or reversing telomere shortening that occurs with each cell division. Epithalon is studied for its ability to activate telomerase, which is why it is classified as a longevity peptide.

Protective caps at the ends of DNA strands; shortening them leads to aging, so lengthening promotes longevity.

A growth hormone-releasing hormone that boosts GH and IGF-1 to reduce visceral fat and support muscle.

An oral tablet that inhibits reuptake of serotonin, noradrenaline, and dopamine for mood enhancement, appetite suppression, energy, and cognition.

Something that increases body heat production to burn more calories and fat.

The progressive shrinkage of the thymus gland that begins in early adulthood and accelerates with age. Since the thymus is where T-cells mature, thymus involution directly causes the decline in adaptive immune function associated with aging. Thymalin is studied for its ability to slow or partially reverse this process.

A 39-amino acid triple GLP-1/GIP/glucagon receptor agonist in the Regulator Series (also called Triple Regulator). Features a C20 fatty diacid side chain and triple receptor activation. Structurally analogous in class to retatrutide. CAS: 2381089-83-2.

Protein-based structures that seal adjacent epithelial cells together, forming a selective barrier that controls what passes between cells into underlying tissue. In the intestinal epithelium, tight junctions are the primary gatekeeping structure of the gut barrier — determining intestinal permeability by regulating paracellular transport. Key tight junction proteins include claudin, occludin, zonula occludens (ZO-1, ZO-2), and junctional adhesion molecules (JAMs). When tight junctions are disrupted — by zonulin signaling, inflammation, or dietary antigens — intestinal permeability increases, the state colloquially called 'leaky gut.' Larazotide (AT-1001) is the most studied peptide tool for tight junction research — it blocks zonulin-induced tight junction disassembly. BPC-157 and KPV address complementary aspects of gut barrier dysfunction (tissue repair and mucosal anti-inflammation, respectively).

Common name for TIA-39-C20 — a triple GLP-1/GIP/glucagon receptor agonist with a C20 fatty diacid chain. Part of the Peptide Receptor Modulator Research Series. The most potent of the three; glucagon receptor activation adds resting energy expenditure and hepatic fat oxidation on top of dual incretin effects.

A long-acting synthetic GnRH (gonadotropin-releasing hormone) agonist decapeptide with approximately 100 times the potency of native GnRH. Triptorelin's primary research application in the peptide community is HPG (hypothalamic-pituitary-gonadal) axis restart after suppression from exogenous testosterone (TRT) or anabolic androgen use. A single 0.1mg dose triggers a powerful LH and FSH flare response that activates the suppressed axis — the restart protocol exploits the rebound luteinizing hormone surge to stimulate Leydig cell testosterone production. Approved medically as Trelstar (USA) and Decapeptyl (EU) for prostate cancer and endometriosis in depot formulations; the restart application uses a very small single dose. For research and educational purposes only. Consult a qualified healthcare professional.

A measurement on insulin syringes for precise peptide dosing; e.g., 10 units might equal 1.5mg depending on dilution.

A 9-amino acid neuropeptide (arginine vasopressin, also called antidiuretic hormone or ADH) produced in the hypothalamus and secreted by the posterior pituitary gland. Vasopressin serves distinct peripheral and central roles. Peripherally, it regulates water reabsorption in the kidneys and causes vasoconstriction. Centrally, V1a receptor signaling in the brain influences pair bonding, social recognition memory, trust, and prosocial behavior — complementary to oxytocin's social bonding effects but with distinct receptor distribution and sex-specific differences. V1b receptors mediate stress axis regulation through ACTH release. In research applications, intranasal vasopressin is studied for social cognition, autism spectrum social behavior, and trust modulation. It is structurally similar to oxytocin (differing by only 2 amino acids) but binds distinct receptor subtypes with different downstream effects. For research and educational purposes only.

A key receptor driving new blood vessel formation. BPC-157 activates VEGFR2 signaling, which is considered one of its primary mechanisms for promoting healing in poorly vascularized tissues like tendons and ligaments.

A small glass bottle holding the peptide powder or reconstituted solution for storage and drawing doses.

The two primary receptors for VIP (Vasoactive Intestinal Peptide) and PACAP, found in the CNS, liver, lung, intestine, and immune cells. VPAC1 binding mediates anti-inflammatory effects. VPAC2 binding is more prominent in the brain and circadian rhythm regulation. VIP's selectivity for these receptors rather than broad immune suppression is what distinguishes it from corticosteroids as an anti-inflammatory agent.

A fundamental cellular signaling pathway governing cell proliferation, differentiation, and tissue homeostasis. Activated by TB-500 in a 2024 study, offering a molecular explanation for how the peptide coordinates multiple tissue repair processes simultaneously.

A mix of BPC-157 and TB-500 for enhanced healing, skin health, and tissue regeneration, named for fast recovery like the comic character.