MOTS-c is a tiny peptide, just 16 amino acids, with the sequence MRWQEMGYIFYPRKLR. What makes it unusual is where it comes from. Most peptides are encoded by genes in the cell nucleus. MOTS-c is encoded inside the mitochondrial genome, within the MT-RNR1 gene that codes for the 12S ribosomal RNA. That puts it in a small class of molecules called mitochondrial-derived peptides.
It was identified in 2015 by Changhan Lee, Pinchas Cohen and colleagues at the USC Davis School of Gerontology, who reported it in Cell Metabolism (Lee et al., 2015). The name stands for "mitochondrial open reading frame of the 12S rRNA type-c."
What it is thought to do
The proposed mechanism centers on energy metabolism. In the original work and later reviews, MOTS-c is described as interfering with the folate–methionine one-carbon cycle. That blocks de novo purine biosynthesis, which causes the intermediate AICAR to build up. AICAR activates AMPK, the enzyme cells use as a fuel gauge. Downstream of AMPK, researchers have reported effects on SIRT1 and PGC-1α (Kim et al. review, 2023).
Under metabolic stress, such as glucose deprivation, MOTS-c has been observed moving into the cell nucleus within about 30 minutes and interacting with stress-response transcription factors including NRF2. Because activating AMPK and boosting glucose uptake in muscle resembles some effects of physical activity, MOTS-c is often labelled an exercise mimetic. That label describes a similarity in cell signalling, not a proven substitute for exercise in people.
What the evidence supports
Most of the data is preclinical. In mice, MOTS-c administration has been linked to reduced diet-induced obesity, improved insulin sensitivity, better physical performance and, in aging studies, longer healthy lifespan. These are animal findings and have not been confirmed as clinical outcomes in humans.
Human work so far is mostly observational, measuring the body's own MOTS-c rather than testing it as a drug. One study found that an acute bout of cycling raised MOTS-c roughly 12-fold in skeletal muscle and modestly in circulation in healthy young men (Reynolds et al., *Nature Communications*, 2021). A separate exercise intervention in breast cancer survivors found changes in MOTS-c that differed between groups (Dieli-Conwright group, *Scientific Reports*, 2021). There are no large randomized trials establishing safety or efficacy of injected MOTS-c for any condition. Reviewers have noted that clinical development has stalled, partly due to delivery challenges.
Regulatory and anti-doping status
MOTS-c is not approved by the FDA for any medical use. Products sold online as MOTS-c sit outside pharmaceutical oversight and are typically labelled research-use-only and not for human consumption.
In sport, MOTS-c is prohibited at all times by the World Anti-Doping Agency, added explicitly to the Prohibited List in 2024. It falls under metabolic modulators (Section S4.4) as an AMPK activator / mimetic (WADA Prohibited List). Athletes in tested sport should treat it as a banned substance.
The buyer-quality angle
Because there is no approved MOTS-c product, anything for sale is an unregulated preparation. Independent COAs from a third-party lab, showing both identity (that the vial actually contains the 16-amino-acid sequence) and purity (no significant related-peptide or solvent contamination), are the only objective signal a buyer has. Treat vendor marketing claims separately from lab evidence. peptideone aggregates public testing data and vendor ratings; it does not sell peptides or test them.
Nothing here is medical or dosing advice. The benefits described in animal studies have not been demonstrated in controlled human trials, and MOTS-c is not an approved therapy.