A study led by researchers at the USC Leonard Davis School of Gerontology is the first to demonstrate that a tiny protein has a big impact on health and longevity in both animals and humans, the university announced Wednesday.
The researchers examined humanin, a peptide encoded in the small genome of mitochondria — the powerhouse of the cell. From experiments in laboratory animals to measurements in human patients, the multi-site collaboration demonstrates how higher levels of humanin in the body are connected to longer lifespans and better health. It is linked to a lower risk for diseases such as Alzheimer’s.
“Humanin has long been known to help prevent many age-related diseases, and this is the first time that it has been shown that it can also increase lifespan,” said senior author Pinchas Cohen, professor of gerontology, medicine and biological sciences and dean of the USC Leonard Davis School.
Humanin has been found not only in human mitochondria but also throughout the animal kingdom, a sign that its related gene has been maintained, or conserved, throughout evolution. The study, which was published online in the journal Aging on Tuesday, examined humanin in several animal species, including worms and mice, as well as humans, including Alzheimer’s patients and children of centenarians.
The results highlight the potential for humanin and other mitochondrial proteins to become treatments for age-related ailments. They also indicate that humanin may be an ancient mitochondrial signaling mechanism that is key for regulating the body’s health and lifespan, said first author and USC Leonard Davis Research Assistant Professor Kelvin Yen.
Humanin levels have previously been observed to decrease with age in many species. In this study, scientists observed higher levels of humanin in organisms predisposed to long lives, including the famously age-resistant naked mole rat, which experiences only a very slow decline in levels of humanin circulating in the body throughout its 30-year lifespan.
“This study, as well as many others, suggest that humanin administration would be an effective therapeutic treatment for a large number of diseases and further solidifies the importance of the mitochondria beyond its traditional role as the `powerhouse of the cell,”’ Cohen said.