Mitochondrial defects caused by rare genetic mutations cause human cells to increase their metabolism. Though that helps short-term survival, it comes at a high cost: a dramatic increase in the rate at which the cells age. Hypermetabolism also may be a key reason why most cells deteriorate as everyone gets older.
“The findings were made in cells from patients with rare mitochondrial diseases, yet they may also have relevance for other conditions that affect mitochondria, including neurodegenerative diseases, inflammatory conditions, and infections,” says principal investigator Martin Picard, Ph.D., associate professor of behavioral medicine at“In addition, hypermetabolism may be a key reason why most cells deteriorate as we get older.
“When cells expend more energy to make proteins and other substances essential for short-term survival, they’re likely stealing resources from processes that ensure long-term survival, like maintaining telomeres,” says Gabriel Sturm, a graduate student and lead author on this study.This hypermetabolic state could explain why people with mitochondrial diseases experience fatigue and exercise intolerance, among other symptoms.
Improving organismal efficiency, which would lower energy use in the cells and improve fatigue and other symptoms, may partially explain the health benefits of exercise in patients with mitochondrial diseases and otherwise healthy people.