Mitochondrial research

Mitochondrial peptides — an overview of the emerging mitokine class

Mitochondrial-derived peptides (MDPs) are a recently characterised class of signalling molecules encoded in the mitochondrial genome that act as systemic stress signals. This overview covers the known MDPs — humanin, MOTS-c, SHLP2 — their receptor targets, and what the mitokine concept means for understanding mitochondria as endocrine organs.

NAD+ and the sirtuin longevity pathway — why mitochondrial redox state governs ageing biology

NAD+ is a coenzyme central to mitochondrial energy metabolism whose decline with age activates the sirtuin longevity pathway deficit. This article covers the NAD+/NADH ratio as a metabolic signal, how sirtuins read it, and what the preclinical data on NAD+ precursors reveals about the sirtuin-PARP competition that determines whether the cell repairs or ages.

MOTS-c — the mitochondrial-encoded peptide that acts as a metabolic stress sensor

MOTS-c is a 16-amino acid peptide encoded within the mitochondrial 12S rRNA gene that translocates to the nucleus during metabolic stress, activating AMPK and the folate-methionine cycle to restore metabolic homeostasis. This article covers its discovery, nuclear translocation mechanism, and what the exercise and metabolic stress data reveals about its role in adaptation.

Humanin and the SHLP family: mitochondrial-derived peptides in ageing and metabolic disease

Humanin and small humanin-like peptides (SHLPs 1–6) are mitochondrial-derived peptides encoded in the 16S rRNA gene. This review examines their cytoprotective, metabolic, and longevity-associated mechanisms.

SS-31 — the mitochondria-targeted peptide and its cardiolipin interaction mechanism

SS-31 (elamipretide) is a tetrapeptide that selectively concentrates in the inner mitochondrial membrane through electrostatic interaction with cardiolipin, restoring electron transport chain efficiency and reducing mitochondrial ROS production. This article covers the cardiolipin biology, the targeting mechanism, and what the preclinical data shows across cardiac, renal, and neurological models.