What are research peptides?

Research peptides are short chains of amino acids — the same building blocks as proteins — synthesized in laboratory settings for use in scientific investigations. Unlike larger protein therapeutics, peptides are typically 2–50 amino acids in length, which confers unique pharmacokinetic properties including targeted receptor binding, relatively rapid degradation, and low immunogenicity. Preclinical studies explore their roles in signaling pathways across metabolic, regenerative, and neuroendocrine systems.

What is a Certificate of Analysis (COA)?

A Certificate of Analysis is a document issued by an accredited analytical laboratory confirming the identity, purity, and potency of a synthesized compound. For research peptides, a COA typically includes HPLC chromatograms, mass spectrometry data, amino acid composition analysis, and solubility data. Independent third-party COAs — generated by labs with no financial relationship to the supplier — are considered the gold standard for verifying compound quality in preclinical research.

What is BPC-157 and what biological mechanisms have been studied?

BPC-157 (Body Protective Compound-157) is a synthetic pentadecapeptide derived from a protein found in human gastric juice. Research has examined its effects on angiogenesis, nitric oxide synthesis, and growth factor receptor modulation. Proposed mechanisms include upregulation of vascular endothelial growth factor (VEGF), interaction with the NO-system to promote vasodilation, and modulation of the dopaminergic and serotonergic neurotransmitter systems. Preclinical studies across rodent models report accelerated tendon-to-bone healing, muscle injury repair, and gastroprotective effects.

What is TB-500 (Thymosin Beta-4) and how does it relate to actin dynamics?

TB-500 is a synthetic version of the 43-amino acid peptide Thymosin Beta-4 (Tβ4), one of the most abundant peptides in mammalian cells. Its primary structural role is the sequestration of globular actin (G-actin), which regulates actin polymerization dynamics essential for cell migration, proliferation, and wound healing. Research has demonstrated that Tβ4 promotes the migration of keratinocytes and endothelial cells into wound sites, stimulates angiogenesis, and reduces inflammation via down-regulation of NF-κB signaling.

What is MOTS-c and how does it relate to mitochondrial signaling?

MOTS-c (Mitochondrial Open Reading Frame of the 12S rRNA type-c) is a 16-amino acid peptide encoded within the mitochondrial genome. It activates AMP-activated protein kinase (AMPK), a central energy-sensing enzyme. Research in mouse models has shown that MOTS-c administration improves insulin sensitivity, reduces high-fat-diet-induced obesity, and extends median lifespan in aged mice. Circulating MOTS-c levels decline with age in humans, making it a subject of longevity research.

What is SS-31 and what is its proposed role in mitochondrial membrane protection?

SS-31 (elamipretide) is a tetrapeptide that selectively partitions into the inner mitochondrial membrane and binds cardiolipin — a lipid essential for cristae structure and the organization of respiratory chain supercomplexes — thereby reducing electron leak, superoxide generation, and cytochrome c release. Animal models of heart failure and ischemia-reperfusion injury have demonstrated improvements in ATP production and reductions in oxidative stress with SS-31 treatment.

What is Retatrutide and what receptor systems does it target?

Retatrutide (LY3437943) is a tri-agonist peptide that activates glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP), and glucagon receptors simultaneously. Published phase 2 clinical trial data (NEJM, 2023) reported mean body-weight reductions of approximately 17% over 24 weeks at the highest dose studied.

What is the CJC-1295 + Ipamorelin combination and why are they studied together?

CJC-1295 is a synthetic analog of growth hormone-releasing hormone (GHRH) that significantly extends its plasma half-life by forming a covalent bond with albumin. Ipamorelin is a selective growth hormone secretagogue receptor (GHSR) agonist that stimulates pituitary GH release through a separate receptor pathway. Combining GHRH analog and GHSR agonist targets both primary regulatory inputs to pituitary somatotrophs, producing synergistic GH pulses in preclinical studies while maintaining physiological pulsatility.

How are synthetic peptides stored to maintain stability?

Lyophilized (freeze-dried) peptides are the most stable form for long-term storage. In powder form, most synthetic peptides remain stable for 12–24 months when stored at −20 °C in a desiccated, light-protected environment. Reconstitution with sterile bacteriostatic water — which contains 0.9% benzyl alcohol as a preservative — allows repeated use from a single vial over several weeks when refrigerated at 2–8 °C.

Tesamorelin: Research Overview

Tesamorelin is a synthetic analog of growth hormone-releasing hormone (GHRH), stabilized against enzymatic degradation. It is one of the most clinically characterized GHRH analogs, studied for its effects on growth hormone secretion and visceral adipose tissue.

Mechanism of action

Tesamorelin carries a trans-3-hexenoic acid modification at the N-terminus that confers resistance to dipeptidyl peptidase-4 (DPP-4) degradation, extending its half-life. It binds GHRH receptors in the anterior pituitary and stimulates endogenous growth hormone release in a pulsatile, physiological pattern, which in turn elevates IGF-1. This preserves the body's normal feedback regulation, unlike continuous exogenous growth hormone.

Visceral fat research

Tesamorelin is notable for a substantial clinical research record. Randomized controlled trials — most prominently in HIV-associated lipodystrophy — documented statistically significant reductions in visceral (trunk) adipose tissue at 26–52 weeks. The proposed mechanism is GH/IGF-1 axis activation preferentially increasing lipolysis in visceral fat depots.

Purity and verification

Pokai Research Tesamorelin is third-party tested by Freedom Diagnostics Testing at 98.86% purity (batch 26030343), with a batch-specific COA and search code published on the product page.

Frequently asked questions

What is the proposed mechanism by which Tesamorelin reduces visceral adipose tissue?

Tesamorelin is a synthetic analog of growth hormone-releasing hormone (GHRH) stabilized by the addition of a trans-3-hexenoic acid group at the N-terminus, which confers resistance to dipeptidyl peptidase-4 (DPP-4) degradation. It stimulates the pituitary to release endogenous growth hormone in a pulsatile, physiological pattern, which in turn elevates IGF-1. The resulting GH/IGF-1 axis activation increases lipolysis preferentially in visceral fat depots — a mechanism demonstrated in randomized controlled trials of HIV-associated lipodystrophy, where significant reductions in trunk fat were observed at 26–52 weeks.

Source: JAMA (2010) · PubMed

What is Tesamorelin?

Tesamorelin is a synthetic analog of growth hormone-releasing hormone (GHRH) studied for its ability to stimulate pulsatile growth hormone secretion. Randomized controlled trials have documented significant reductions in visceral adipose tissue, making it one of the most clinically characterized GHRH analogs in published research.

Source: JAMA (2010) · PubMed

What is the role of IGF-1 in growth hormone axis research?

Insulin-like growth factor 1 (IGF-1) is produced primarily in the liver in response to GH stimulation and mediates many of GH's downstream anabolic effects, including protein synthesis, cell proliferation, and bone mineral density maintenance. Serum IGF-1 levels serve as the primary clinical biomarker for GH axis activity because, unlike GH itself which is secreted in short pulses, IGF-1 has a longer plasma half-life and provides an integrated measure of GH secretion over hours to days. Research examining GHRH analogs like CJC-1295 and tesamorelin consistently uses IGF-1 as a primary pharmacodynamic endpoint in addition to direct GH pulse analysis.

Source: Growth Horm IGF Res (2012) · PubMed

How is peptide purity measured and why does it matter?

Peptide purity is typically assessed by reverse-phase high-performance liquid chromatography (HPLC) and confirmed by mass spectrometry. These techniques quantify the proportion of the target compound relative to impurities such as deletion sequences, oxidized variants, or solvent residues. Research applications require high purity — commonly ≥98% — to ensure that observed biological effects can be attributed to the intended molecule rather than contaminants. Independent third-party certificates of analysis (COAs) provide an objective record of purity at the time of synthesis.

Source: J Pept Sci (2019) · PubMed

View Tesamorelin in the catalog →