Mitochondria · Humanin
Humanin: the first mitochondrial-derived peptide
October 16, 2026 · 1 min read · Models: Cell culture, Mouse
Humanin was discovered in 2001 in a screen for factors that protect neurons from Alzheimer’s-associated toxicity. Encoded within mitochondrial 16S rRNA, it has since been studied as a cytoprotective signal acting through both intracellular partners and cell-surface receptors.
A summary of published research for scientific reference. It is not medical advice and does not describe or endorse use in humans or animals. Findings from cell culture and animal models often do not carry over to other systems.
Discovery by functional screening
Hashimoto and colleagues (PNAS, 2001) screened a cDNA library from an Alzheimer’s disease brain region for sequences that rescued neuronal cells from death caused by familial AD gene mutants and amyloid-β. The protective clone encoded a 24-amino-acid peptide they named humanin. It mapped to the mitochondrial 16S rRNA gene.
Mechanisms studied
Intracellularly, humanin binds the pro-apoptotic protein Bax and prevents its translocation to mitochondria. Extracellularly, it signals through a receptor complex that includes CNTFR, WSX-1 and gp130, and through formyl-peptide receptor-like 1. This activates STAT3 and other survival pathways.
Synthetic analogs, notably S14G-humanin (HNG), show greater potency in cell assays. They have been used in rodent models of ischemia, metabolic stress and neurodegeneration.
Aging research
Circulating humanin levels decline with age in mice, and some long-lived models have higher levels. These are associations. Disentangling cause from correlate remains an open problem for the mitochondrial-peptide field.
References
- Hashimoto Y, Niikura T, Tajima H, et al. A rescue factor abolishing neuronal cell death by a wide spectrum of familial Alzheimer’s disease genes and Aβ. Proc Natl Acad Sci USA. 2001;98(11):6336–6341.
- Guo B, Zhai D, Cabezas E, et al. Humanin peptide suppresses apoptosis by interfering with Bax activation. Nature. 2003;423:456–461.