MOTS-c

Research-Grade

MOTS-c (Mitochondrial Open Reading-frame of the Twelve S ribosomal RNA type-c) is a 16-amino-acid peptide encoded within the mitochondrial 12S rRNA gene — making it one of only a handful of known mitochondrial-derived peptides (MDPs) translated from mtDNA rather than nuclear DNA. It was identified in 2015 by Changhan David Lee and colleagues at the University of Southern California, who demonstrated that MOTS-c activates the AMPK signaling pathway through modulation of the folate-methionine one-carbon cycle, enhancing skeletal-muscle glucose uptake and fatty-acid oxidation. This AMPK-mediated mechanism produces effects that closely mirror the metabolic benefits of physical exercise — earning MOTS-c the designation of an exercise-mimetic peptide. Preclinical studies have consistently shown improved insulin sensitivity in high-fat-diet rodent models, reduced adiposity without caloric restriction, enhanced physical performance in aged mice, and extended healthspan markers. Notably, exercise itself acutely increases endogenous MOTS-c release from skeletal muscle mitochondria, suggesting a bidirectional relationship between this peptide and physical activity. MOTS-c belongs to the emerging mitokine class alongside humanin (a cytoprotective MDP from the 16S rRNA gene) and is mechanistically complementary to SS-31/elamipretide (which stabilizes cardiolipin in mitochondrial inner membranes). MOTS-c expression declines measurably with age in human tissues, paralleling the well-documented decline in mitochondrial function that is a recognized hallmark of aging. This age-related decline provides the rationale for exogenous MOTS-c administration as a potential intervention against metabolic deterioration. Early human data is emerging — small studies have examined circulating MOTS-c levels in diabetic versus healthy populations and in response to exercise — but no large-scale interventional human trial has been completed. The peptide is classified as a research compound worldwide and is not approved for therapeutic use in any jurisdiction, though it is widely used off-label in longevity and metabolic health protocols, typically administered subcutaneously at 5-10 mg several times per week.