What is MOTS-c?
The 2015 primary publication describes MOTS-c as a 16-amino-acid peptide encoded within mitochondrial 12S rRNA. It introduced a research framework in which a mitochondrial-derived peptide participates in metabolic signaling.
What was studied?
The original work used cellular and animal experiments to investigate metabolic homeostasis and insulin-sensitivity-related biology. Its findings are model-specific observations, not a clinical evaluation of a commercially supplied research material.
A second mechanistic question
A 2018 study examined movement of MOTS-c to the nucleus and regulation of gene expression during metabolic stress. This adds a mechanistic layer to the literature; it does not make a cellular mechanism equivalent to an established clinical outcome.
How to compare studies
Separate endogenous peptide measurements, cell experiments, animal interventions and human studies. Note what was measured and how the investigators characterized the material. Similar topic labels can conceal very different experimental questions.