Humanin is a naturally occurring micro-peptide unique for the fact that it is encoded in the mitochondrial DNA (mitochondria contain a small amounts of DNA that is exclusive only to them). It functions as a cytoprotective protein, protecting cells from the process of apoptosis (programmed cell death) via interference with the normal operation of the Bcl2-associated X protein (Bax). Variations of humanin have been found in a number of mammals from humans to rats and is highly conserved across species. Research shows that humanin is important in protecting neurons, cardiac tissue, muscle cells, the retina of the eye, and the lining of blood vessels.
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