Peptide Research Database

Research-backed information on peptides — dosage, half-life, risks, and the latest peer-reviewed studies from PubMed.

91peptides
11categories
1214research papers

5-Amino-1MQ

Weight LossMetabolic

A small molecule inhibitor of nicotinamide N-methyltransferase (NNMT), an enzyme significantly overexpressed in white adipose tissue of obese individuals. Not technically a peptide but commonly sold alongside peptides in weight management protocols. Works by preserving cellular NAD+ and SAM pools, shifting fat cells from a storage to a fat-burning metabolic state.

Half-life:12-16 hours (limited pharmacokinetic data)

AICAR

MetabolicBodybuilding

5-Aminoimidazole-4-carboxamide ribonucleotide — an endogenous intermediate of purine biosynthesis that activates AMP-kinase (AMPK), the cellular energy sensor triggered by exercise. Mimics the metabolic effects of endurance exercise at the cellular level, enhancing fat oxidation, glucose uptake, and mitochondrial biogenesis. Banned by WADA as a metabolic modulator after detection in professional cycling.

Half-life:2-3 hours

GLP-1

Weight LossMetabolic

The native incretin hormone produced by intestinal L-cells in response to food intake. The endogenous molecule that semaglutide, tirzepatide, and all GLP-1 receptor agonist drugs are designed to mimic. Understanding native GLP-1 is essential to understanding the entire drug class. Not used therapeutically due to its extremely short half-life from rapid DPP-4 enzymatic degradation.

Half-life:1-2 minutes

Humanin

Anti-AgingCognitiveMetabolic

A 24-amino-acid mitochondrial-derived peptide (MDP) encoded within the 16S rRNA gene of mitochondrial DNA. Related to MOTS-c but with distinct cytoprotective mechanisms. Protects cells against oxidative stress, apoptosis, and age-related degeneration by interacting with BAX (pro-apoptotic protein) and IGFBP-3. One of the most studied peptides in longevity research, with evidence of declining levels in aging tissues.

Half-life:0.5-4 hours (varies by analogue; HNG has extended activity)

Insulin

BodybuildingMetabolic

A 51-amino-acid peptide hormone essential for glucose metabolism and the most potent anabolic hormone in the body. FDA-approved for diabetes management under multiple brand names and formulation types (rapid, short, intermediate, and long-acting). Used in advanced bodybuilding for extreme nutrient shuttling and synergistic anabolic effects with GH and IGF-1, but carries the highest acute risk of any compound used in performance enhancement.

Half-life:Rapid-acting (Humalog/Novolog): 1 hour | Regular (Humulin R): 1.5 hours | Long-acting (Lantus): 24 hours

Kisspeptin-54

Sexual HealthMetabolic

The full-length 54-amino-acid form of kisspeptin — the master upstream regulator of the reproductive hormone axis. More potent and longer-acting than Kisspeptin-10 due to additional receptor-binding domains in the longer sequence. Being studied for fertility treatment, hypogonadism diagnosis, and reproductive disorders. May offer a more physiological approach to stimulating reproductive hormone production than GnRH or HCG.

Half-life:28 minutes (IV); longer subcutaneously

L-Carnitine

Weight LossMetabolic

A naturally occurring amino acid derivative that serves as the sole carrier molecule for transporting long-chain fatty acids into mitochondria for beta-oxidation (energy production). Produced endogenously from lysine and methionine, primarily in the liver and kidneys. One of the most widely used fat-metabolism supplements, with FDA-approved pharmaceutical forms available for carnitine deficiency states.

Half-life:2-3 hours (injectable); oral bioavailability 15-25%

Lipo-C

Weight LossMetabolic

A multi-component lipotropic injection containing methionine, inositol, and choline (the MIC complex) plus B vitamins and L-carnitine. Targets multiple aspects of hepatic fat metabolism, methylation, and mitochondrial fatty acid oxidation. One of the most commonly prescribed supportive treatments in weight loss clinics, typically used alongside caloric restriction and exercise.

Half-life:Variable by component; effects are cumulative with regular dosing

Liraglutide

Weight LossMetabolic

A GLP-1 receptor agonist with 97% structural homology to native GLP-1 and the predecessor to semaglutide. FDA-approved for both type 2 diabetes (Victoza) and obesity (Saxenda). One of the most prescribed weight loss medications worldwide, with extensive long-term safety data including cardiovascular outcome trials demonstrating reduced risk of major adverse cardiovascular events in diabetic patients.

Half-life:13 hours

MOTS-C

MetabolicAnti-Aging

A mitochondrial-derived peptide (MDP) encoded within the 12S rRNA gene of mitochondrial DNA. Acts as an exercise mimetic, producing many of the metabolic benefits of physical exercise without the exercise itself — improving insulin sensitivity, glucose uptake, and fatty acid oxidation. Discovered at the University of Southern California in 2015, MOTS-c is one of the first identified signaling molecules encoded by the mitochondrial genome rather than nuclear DNA.

Half-life:4-8 hours

NAD+

Anti-AgingMetabolic

Nicotinamide Adenine Dinucleotide — an essential coenzyme present in every living cell, required for over 500 enzymatic reactions including cellular energy production, DNA repair, and sirtuin-mediated gene regulation. NAD+ levels decline by approximately 50% between ages 40 and 60, contributing to mitochondrial dysfunction and aging. Supplementation via IV infusion, oral precursors (NMN/NR), or injection aims to restore youthful NAD+ levels.

Half-life:IV: effects persist 48-72 hours (2-3 days) | Oral precursors (NMN/NR): 2-4 hours

SLU-PP-332

MetabolicBodybuilding

An ERRα (estrogen-related receptor alpha) agonist developed at Washington University. A next-generation exercise mimetic that enhances endurance capacity and promotes slow-twitch muscle fiber transformation through a completely different mechanism than AICAR. Activates the same transcriptional programs that endurance training induces, including mitochondrial biogenesis and oxidative metabolism genes.

Half-life:Estimated several hours (limited pharmacokinetic data)

Vitamin B12

Metabolic

Cobalamin — an essential water-soluble vitamin required for DNA synthesis, nerve function (myelin maintenance), and red blood cell formation. Deficiency is common, particularly in vegans, the elderly, those on metformin or proton pump inhibitors, and individuals with pernicious anemia. Injectable forms bypass the complex GI absorption pathway (requiring intrinsic factor), making them the treatment of choice for severe deficiency and malabsorption.

Half-life:Hepatic stores last years; circulating methylcobalamin: 144 hours (6 days)

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