# TSMMA Peptides — Metabolic & Weight Research Peptides > TSMMA Peptides is a reference desk for Metabolic & Weight Research peptides — MOTS-c and tesamorelin — summarized from peer-reviewed literature. A digest, not a vendor or clinic. A focused reading desk for the published science on MOTS-c and tesamorelin — what each was actually studied for, in which species, and how strong the evidence really is. ## The short version TSMMA Peptides is a reading desk, not a store. It collects what the published research literature actually says about two peptides that appear at opposite ends of the metabolic research spectrum: **MOTS-c** and **tesamorelin**. A *peptide* is a short chain of amino acids — the same building blocks that make up proteins, only much smaller. Each of these two has been studied because it seems to influence the body's metabolic machinery in a distinct way: MOTS-c activates AMPK (an energy-sensing enzyme) by inhibiting the folate cycle inside skeletal muscle cells, while tesamorelin stimulates the pituitary gland to release growth hormone, which then preferentially breaks down visceral fat. This guide does one job: it tells you, in plain language and with citations, what each peptide was tested on, in which species, and how far that evidence really reaches. One has no approved use in humans; the other holds an FDA approval, but only for a specific HIV-related condition. We do not sell anything, we do not give medical advice, and we never list a human dose. ## What are research peptides? Proteins in your body — the enzymes that run digestion, the hormones that regulate hunger, the collagen that holds tissue together — are long chains of amino acids folded into precise shapes. A *peptide* is a much shorter chain of the same amino acids, sometimes only a handful of links long. Because they are small and specific, peptides can act like keys fitting particular locks (receptors) on cell surfaces, switching certain processes on or off. A *research peptide* is one that has been synthesized and studied in the laboratory — in cell cultures, in animals, occasionally in early human pilots or controlled trials — but may or may not hold a regulatory approval. The term covers a wide range: a compound like MOTS-c that has never been given to humans in a formal efficacy trial, and a compound like tesamorelin that completed Phase 3 RCTs and earned an FDA approval for a narrow indication. When this desk reports a number, it reports it the way the study did — for example, *tesamorelin 2 mg/day reduced visceral fat by a net 42 cm2 in HIV-positive adults* — never as a recommendation for any reader. ## How these two fit into metabolic research MOTS-c and tesamorelin approach metabolism from different directions, which is exactly what makes them interesting to read together. - [**MOTS-c**](/mots-c) is the lead. It is a 16-amino-acid peptide that the body itself makes — encoded not in nuclear DNA but in the mitochondrial genome, the genetic remnant inside the cell's power stations. Its best-understood role is activating AMPK in skeletal muscle by inhibiting the folate cycle [6]. Exercise raises circulating MOTS-c, and exogenous MOTS-c extended physical performance in mice across a broad age range [4]. The challenge: every human study so far is observational. No human efficacy trials exist. - [**Tesamorelin**](/tesamorelin) sits at the opposite end of the evidence spectrum. It is a synthetic analogue of the body's own growth-hormone-releasing hormone — the signal the brain sends to the pituitary to release growth hormone — stabilized by a chemical modification that helps it resist rapid breakdown [9]. Across five randomized controlled trials in HIV-positive adults with lipodystrophy (antiretroviral-related fat redistribution), tesamorelin reduced visceral fat by a mean of roughly 28 cm2 and hepatic fat by about 4% [8]. It is FDA-approved for that specific use and prohibited in sport. Together they frame two different research strategies: mining the body's own mitochondrial signals for metabolic leverage, and engineering a stabilized version of an existing hormonal axis signal. Use the directory to read each one, or [compare these peptides](/compare) side by side. ## A note on how this desk reads the literature TSMMA Peptides is a cross-referenced literature digest. Each compound page summarizes the peer-reviewed studies for that peptide, cites them by number, and links to a single shared [references list](/references) that aggregates every source across both. Where the evidence is thin, single-lab, or preclinical, we say so plainly. Where a regulatory approval is narrow — applying only to a defined population in a defined condition — we describe exactly what is and is not within the approved scope. We describe research findings and the cited cautions that accompany them; we do not recommend, prescribe, or sell. The aim is a precise, honest map of what is known, so you can see where the science is established and where it is still exploratory. --- A literature digest tracing two metabolic signals from mitochondria and pituitary to the edge of clinical evidence — citations only, never a clinic, never a vendor.