Compound research & mechanism explainers

The investigational triple agonist (LY3437943): GLP-1, GIP and glucagon receptor targets, molecule properties, and what its published trials investigated.

How TB-500 relates to thymosin β4, the actin-sequestration biochemistry, and the predominantly preclinical models researchers have examined.

The copper tripeptide: copper(II) coordination chemistry, the mechanisms studied in fibroblast and gene-expression models, and evidence status.

A GHRH analog: the receptor mechanism and GH/IGF-1 axis, what the HIV-lipodystrophy trials measured, and its regulatory status.

A peptide encoded in mitochondrial DNA: AMPK/folate-cycle and mitochondrial-to-nuclear signalling, characterised mainly in cell and rodent models.

The coenzyme (not a peptide): its redox role, use as a substrate by sirtuins/PARPs/CD38, the NMN/NR precursor distinction, and appearance/stability.

A synthetic ACTH(4-10) analog: BDNF/TrkB and dopaminergic mechanisms, ischemia models, and the largely Russian-published evidence base.

A tuftsin-analog heptapeptide: GABAergic, BDNF, enkephalin and neuroimmune mechanisms examined, with honest treatment of the Russian literature.

A selective GH-secretagogue pentapeptide: the ghrelin-receptor (GHS-R1a) mechanism kept distinct from GHRH analogs, and the largely preclinical evidence base.

A GHRH analog: the GHRH-receptor mechanism, the DAC vs no-DAC (mod-GRF 1-29) chemistry distinction, and what published studies investigated.

A GHRH analog and the GH/IGF-1 axis — cross-referenced with the growth-hormone-secretagogue family.

A long-acting IGF-1 analog: receptor biology, IGFBP-binding and half-life properties studied in cell and animal models.

A synthetic fragment of growth hormone (hGH 177-191): the mechanisms researchers examined and its human-trial research history.

A melanocortin (MC1R/MC4R) receptor agonist: the melanocortin-system pharmacology studied in preclinical models.

A KISS1/GPR54 ligand upstream of GnRH: the HPG-axis signalling researchers have investigated.

The C-terminal α-MSH tripeptide (Lys-Pro-Val): the NF-κB / anti-inflammatory pathways examined in cell and rodent models.

A 28-amino-acid immunomodulatory peptide (Zadaxin): the immune-signalling mechanisms and clinical literature, reported neutrally.

A cardiolipin-binding Szeto-Schiller tetrapeptide (elamipretide): the mitochondrial mechanism studied in cell, animal and trial settings.

A phenothiazine dye (not a peptide): its redox chemistry and the electron-transport and enzyme mechanisms the literature has examined.

A synthetic tetrapeptide (Ala-Glu-Asp-Gly): the telomerase-expression and pineal mechanisms examined, largely in Russian/preclinical work.

Delta sleep-inducing peptide: the sleep-regulation and neuromodulatory roles investigated in a largely older, sparse literature.

A small-molecule NNMT inhibitor: the metabolic mechanisms examined in early, largely preclinical research.

An ERRα/β/γ agonist: the mitochondrial and metabolic pathways studied so far only in rodent models.

An angiotensin-IV-derived compound (HGF/c-Met modulator): the synaptogenesis mechanisms examined in preclinical models.

A porcine-brain peptide preparation: the neurotrophic mechanisms and the stroke/dementia clinical literature, reported neutrally.

What is in the Wolverine research blend — BPC-157 and TB-500 — with links to each component’s research and a plain note that the combination itself is unstudied.

What is in the GLOW research blend — GHK-Cu, BPC-157 and TB-500 — with links to each component’s research and a plain note that the combination itself is unstudied.

What is in the KLOW research blend — BPC-157, GHK-Cu, TB-500 and KPV — with links to each component’s research and a plain note that the combination itself is unstudied.

What is in the CJC-1295 + Ipamorelin blend, the different receptors each component targets, and a plain note that the combination itself is unstudied.

What “bacteriostatic water” means as a material, how pharmaceutical water grades differ, and what documented quality looks like — a neutral reference, not a preparation guide.

The materials-science of keeping lyophilized and in-solution peptides stable — temperature, light, moisture and freeze-thaw. A stability reference, not a prep or dosing guide.

How a genuine lyophilized vial appears — cake vs residue, colour, red flags — and why appearance is a first check, not proof of identity.

Reading a Certificate of Analysis critically — mismatched lot numbers, generic templates, missing methods — and how to verify a batch independently.

The two-pillar purity check — HPLC purity and mass-spec identity — how to weigh an independent testing lab, and how to confirm the certificate belongs to your exact batch.

Why a generic marketplace listing can differ from a lab-assembled, COA-backed research vial — sourcing, identity, purity documentation and traceability. Neutral, no seller claims.

A neutral buyer-education guide to the global geography of peptide manufacturing — and why per-batch HPLC purity and mass-spec identity, not the country on the label, are what determine quality.

Sterility, endotoxin and the EU unit explained as quality attributes of research materials, and why they matter for reproducible lab work. A concepts reference, not safety advice.

Glutathione as a research material — its tripeptide chemistry, reduced vs oxidized form, and how identity, purity and sourcing are documented. No health or benefit claims.

How to verify a retatrutide research vial — identity, purity, COA and batch lookup. A verification reference; the science lives on the retatrutide research page.

The dual GIP/GLP-1 receptor agonist (LY3298176): molecule design, the SURPASS and SURMOUNT trial programs, and how it differs from the triple agonist retatrutide.

The pentadecapeptide gastric-juice fragment: molecule properties, the pleiotropic mechanisms researchers have examined, and the overwhelmingly preclinical evidence base.

The cyclic nonapeptide: du Vigneaud’s synthesis, the OXTR receptor and Gq/PLC signalling, and the molecular and neuroscience mechanisms studied. Chemistry and receptor pharmacology only.

A synthetic Glu-Asp-Arg tripeptide from the Khavinson short-peptide work — what the sparse, largely preclinical literature has examined, and an honest note on how thin the evidence is.

The single-receptor GLP-1 agonist: acylation chemistry inherited from liraglutide, and what the SUSTAIN, STEP, PIONEER and SELECT programmes investigated.

The once-daily GLP-1 analogue (NN2211) the whole class descends from — the published structure–activity study behind it, its measured half-life, and the LEAD, LEADER and SCALE trials.

A long-acting amylin analogue, not a GLP-1 agonist: calcitonin-receptor/RAMP pharmacology, the amyloid design problem, and why cagrilintide alone is not CagriSema.

The GCGR/GLP-1 dual agonist (BI 456906): its oxyntomodulin template, the biomarkers used to prove each receptor arm is engaged, and the phase 2 and SYNCHRONIZE trials.

The other GLP-1/glucagon dual agonist (IBI362 / LY3305677): an Eli Lilly molecule developed by Innovent, and an evidence base built entirely in Chinese trial populations.

GHRH(1-29)-amide — the shortest fully active fragment of growth-hormone-releasing hormone: the GHRH-receptor mechanism, the paediatric and diagnostic literature, and its discontinued regulatory record.

Pralmorelin: the ghrelin-receptor hexapeptide that became a pituitary-function test agent — GHRH-independent action, the ACTH response, and the five-day study that reported attenuation without an IGF-1 rise.

The 1984 original: the synthetic hexapeptide whose receptor was cloned after it, and whose natural ligand — ghrelin — was found by following it. Plus the appetite and adiposity work that makes it non-selective.

GHRP-6 plus one methyl group, with a second molecular target: CD36 in the heart, the GH-independent cardiac work in animal models, and the 16-week human study reporting partial reversible desensitisation.

Not a peptide — an orally active non-peptide small molecule at the same ghrelin receptor, and the compound with the largest randomised-trial record in the class: consistent target engagement, endpoints not met.

The cyclic lactam heptapeptide built from the α-MSH message sequence: melanocortin MC3R/MC4R pharmacology, the amide-versus-acid relationship to melanotan-2, and what the published RECONNECT trial program measured.

Native GnRH itself, not an analogue: the 1971 Schally/Guillemin isolation, the GnRH receptor, and the classic pulsatile-versus-continuous experiments that separate the decapeptide from the synthetic superagonists.

The only human cathelicidin: hCAP18 processing, the conditional amphipathic helix, the antimicrobial and innate-immunity mechanisms examined, and a plain account of its dual pro-/anti-inflammatory behaviour and narrow concentration window.

The family overview: the St Petersburg short-peptide programme, the proposed peptide–DNA gene-regulation mechanism and how much of it is demonstrated, and an honest account of an evidence base concentrated in one research group.

The Lys-Glu dipeptide with the family’s largest primary record: rodent lifespan and carcinogenesis studies, chromatin work, gene expression in ageing cell culture — and no independent replication in 25 years.

The Ala-Glu-Asp-Pro tetrapeptide made by directed synthesis from the cortexin extract: sciatic-nerve regeneration studies, a mouse-heart microarray screen, and two published null results.

The Lys-Glu-Asp tripeptide assigned to vascular tissue: differentiation markers in fibroblast culture, molecular docking against the MKI67 promoter, one uncontrolled human report and one null result.

The only compound in the family with a non-human primate study: glucose-load work in old rhesus monkeys, pancreatic differentiation factors in culture, and a small unblinded human report.

The tetrapeptide whose own primary literature disagrees on its sequence — and which carries the clearest Khavinson-free rodent work found anywhere in this family.

Designated a chondroprotector, studied in skin, kidney and stem cells: the code-name problem (AED = T-31) and the absence of any published cartilage work.

Two rodent studies, one of them a sarcoma model, and a cardiac designation that traces to a patent rather than a paper. A short page, because the literature is short.

Almost the entire published record is chromatin calorimetry in cultured lymphocytes rather than anything to do with the organ the name points at.

Exactly one indexed primary study exists, and it reports a partial null. The shortest page in this library, deliberately.

The IGF-1Ec splice variant and the 24-residue E-domain peptide sold under its name: two things with one label, no identified receptor, and a published replication attempt that found no effect on myoblasts.

What PEGylation demonstrably does to a peptide — hydrodynamic radius, renal clearance, protease shielding — and the plain fact that no peer-reviewed characterisation of this particular conjugate has ever been published.

The des(1-3) truncation of native IGF-1: three residues removed, IGF-binding-protein affinity lost, and the pig and marmoset study reporting more potent and prolonged hypoglycaemic action that vendor pages leave out.

Not an agonist — the brake itself. The 1997 knockout mouse, double-muscled cattle, the whippet mutation and a single human case, and why recombinant myostatin exists as the reference ligand in inhibition assays.

The endogenous antagonist: what the 344 actually refers to, direct high-affinity myostatin binding, the AAV1.CMV.FS344 gene-therapy trials, and the published rebuttal disputing their functional claims.

A soluble ActRIIB-Fc receptor decoy whose Duchenne trial was stopped early for epistaxis and telangiectasias — plus the analysis finding that none of 14 black-market products contained the labelled molecule.

Eleven residues taken from the aqueous face of erythropoietin’s helix B, engineered to engage the innate repair receptor while being non-erythropoietic — plus the small placebo-controlled trials in sarcoidosis neuropathy and type 2 diabetes.

The first mitochondrial-derived peptide: found in a 2001 Alzheimer’s cDNA screen, encoded in the mtDNA 16S rRNA region, with two unreconciled mechanisms, the S14G analogue, and no interventional human data.

Vasoactive intestinal peptide: the 1970 Said and Mutt isolation, the amidated 28-residue sequence, the VPAC1/VPAC2/PAC1 receptor nomenclature, and the two aviptadil trials that both missed their primary endpoints.

A seven-residue fragment designed from how spadin breaks down in blood, reported to block the TREK-1 potassium channel at sub-nanomolar potency — and a plain account of how single-laboratory the evidence is.

The CNTF-derived compound Ac-DGGLAG-NH₂ and the Peptide 6 lineage behind it: rodent neurogenesis and Alzheimer’s-model work from one laboratory, no human data, and why it is not the p21 cell-cycle protein.

The retro-inverso peptide built to disrupt the FOXO4–p53 interaction: the 2017 Cell paper with its tolerability qualifier, the 2025 NMR structure, the study reporting worse pulmonary outcomes, and zero human trials.

Per-component reference data for the most-searched two-peptide pairing, a documented search of PubMed, Europe PMC and ClinicalTrials.gov finding no study of the combination, and why a two-component vial is harder to verify.

The one peptide combination with a real phase 3 programme: what REDEFINE 1, 2 and 5 randomised, what they reported, and the design limits — a 7:1 arm imbalance and a sponsor-run trial — that bound how far those results reach.

Two intensively studied incretin molecules with overlapping receptor targets and zero studies of the pair — including why TRIUMPH-5, the one phase 3 trial containing both, randomises participants to one or the other.

A GHRH-receptor agonist paired with a ghrelin-receptor agonist. Real co-administration research exists for other GHRH/secretagogue pairs — and this page is precise about where that literature stops applying to this one.

Not a peptide: a ~63 kDa IgG4 Fc fusion protein expressed in CHO cells, roughly fifteen times the size of semaglutide — the engineering paper, AWARD and REWIND, and why a peptide COA answers fewer questions here.

The prohibitin-homing peptidomimetic from the Arap and Pasqualini lab: the obese-monkey study that reported renal proximal tubule changes alongside weight loss, the published comment disputing the mechanism, and a first-in-man trial terminated after four participants.

A nucleoside, not a peptide: conversion to ZMP and AMPK activation, the question mark in its own founding paper, a human study where the readout moved but AMPK did not, the futility-stopped RED-CABG phase 3, and its WADA-prohibited status.

An investigational injectable in active development: four peer-reviewed phase 2 trials including a phase 2b with MRI, phase 3 registered but not yet recruiting, every published result sponsor-authored — and no public chemical structure at all.

Not a peptide: the carnitine shuttle and CPT1/CPT2 biochemistry, OCTN2 and primary carnitine deficiency, the post-infarction meta-analyses that disagree, the TMAO findings — and why chiral analysis, not mass spec, settles its identity.

The linear [Nle4, D-Phe7]-α-MSH analogue from 1980 that became an approved drug: MC1R pharmacology, the two NEJM placebo-controlled phase 3 trials in erythropoietic protoporphyria, and a hard structural split from Melanotan-2.

The indoleamine hormone: AANAT as the rhythm-generating enzyme, MT1/MT2 receptor pharmacology, the human phase-response curve twelve hours out of phase with light — and the JAMA and JCSM analyses finding commercial products do not match their labels.

A formulator’s reference: the Ac-EEMQRR-NH₂ sequence, a PubChem structural error that breaks mass-spec identity checks, the CIR’s 0.005% ceiling against the founding study’s 10% — and the independent split-face trial that found no significant effect.

A trademark, not a molecule: Palmitoyl Tripeptide-1 plus Palmitoyl Tetrapeptide-7, with verified sequences and masses — and a clear separation from the original Matrixyl (pal-KTTKS), whose 93-subject, 3 ppm P&G study is not evidence for this blend.

Argireline with two more residues, verified sequence and mass — and a deliberately short page, because a search of the indexed literature for this INCI name returns no standalone study of the ingredient at all.

Ac-Lys-Gly-His-Lys-NH₂, the defined peptide inside Capixyl: verified identity data, its real relationship to the GHK motif, a naming collision in the public record, and a 32-subject trial whose “comparable to minoxidil” rests on a null result.

Contains no venom: a peptidomimetic modelled on waglerin-1 from the temple pit viper. Verified structure and mass, the venom peptide’s real receptor pharmacology kept separate — and one indexed study, which docked against targets unrelated to the marketing.

Acetyl Tetrapeptide-3 plus a biochanin-A-rich red clover extract, with citable use levels — and the widely-quoted 30-man trial traced back to the 2013 Lucas Meyer technical file it actually came from.

It contains no peptide: two stabilised polyphenol glucosides, glycine and zinc. Identity data for each parent compound, the 1–3% use range, and the 26-man proof-of-concept traced to a 2014 Givaudan technical file.

One methyl group away from GHK-Cu and nowhere near it on evidence: verified identity data for peptide and complex, no INCI name we could find, and a literature amounting to one 2007 ex-vivo study with a non-significant endpoint.

The one ingredient here with a solid evidence base: the CIR safety assessment and its 2% figure, the ~100 kDa penetration threshold, a registered 36-subject randomised trial — and why molecular weight distribution, not purity, is the specification that matters.

The single-chain B-chain-only analogue of relaxin-2 reported as the first functionally selective RXFP1 agonist: the pERK-over-cAMP bias, the rodent fibrosis and infarct models, and a six-minute serum half-life its own developers are still trying to fix.

The 33-residue hypothalamic neuropeptide with two names and two disulfide bonds: the twin 1998 discoveries, the non-selective OX1R/OX2R profile, the narcolepsy findings that made it the CSF analyte, and why a routine COA cannot confirm its disulfide pairing.

The linear 28-residue sibling from the same precursor: its two-helix NMR structure, the modest OX2R preference that is routinely overstated, the canine narcolepsy mutation behind the OX2 receptor’s prominence, and why it is the easier of the pair to certify.

The frog-skin heptapeptide that forced biochemistry to accept D-amino acids in vertebrates: the 1987 post-translational isomerisation result, its mu-opioid pharmacology, its Class 1 status in horse racing, and why mass spectrometry cannot prove its stereochemistry. Chemistry and analysis only.

A p53 fragment fused to a membrane-penetrating leader, and a careful account of the gap between what its studies measured and what is claimed about it online: the membrane-HDM-2 hypothesis, one substantial independent animal study, and zero human clinical evidence.

The competitor peptide built to block the CXXC5–Dishevelled interaction and release a brake on Wnt signalling: mouse wound and hair studies from one Korean laboratory, a disclosed commercial interest, and the small molecule that same group moved to instead.

The Glu-Asp-Gly tripeptide of the Khavinson family, completing the bioregulator cluster: one indexed primary study, no animal or human data, no support for its lung designation, and the 127-Da mass gap that separates it from Bronchogen.