Humanin

[10][11] Humanin is the most well-conserved of the mitochondria-derived peptides, found in such diverse species as humans, naked mole rats, and nematodes.

[5] Overexpression of humanin in Caenorhabditis elegans has been shown to extend the lifespan of that nematode by increasing autophagy.

[5] The rat, Rattus norvegicus, has a gene, rattin (C0HLU6, "Humanin-like protein"), that encodes a 38 amino acid peptide homologous to humanin.

[12] The peptides are 81% identical, with the carboxyl terminal sequence in rattin being 14 amino acids longer than in humanin.

The first to publish, in 2001, was the Nishimoto lab, which found humanin while looking for possible proteins that could protect cells from amyloid beta, a major component of Alzheimer's disease.

[23][24][25] Beyond the possible neuroprotective effects, humanin protects against oxidative stress, atherosclerotic plaque formation, and heart attack.

[32] Rattin shows the same ability as humanin to defend neurons from the toxicity of beta-amyloid, associated with the degeneration in Alzheimer's disease.