According to a study published in the journal Communications Biology, human cells with impaired mitochondria respond by kicking into a higher gear and expending more energy. This phenomenon is called hypermetabolism in which state the cells′ short-term survival is increased. However, it comes at a higher cost, i.e., a dramatic increase in the rate of cell aging.

The lead author of the study stated that these findings were made after observing the cells of a patient with rare mitochondrial diseases. He added that this state of cells might be associated with other conditions, such as neurodegenerative diseases, inflammatory conditions, and infections. He explained that in most cases, it is thought that mitochondrial defects will force the cells to slow their metabolic rate to conserve energy. 

However, by analyzing the cells of patients with mitochondrial diseases, the researchers found that cells with impaired mitochondria doubled their energy expenditure. Although it keeps the cells running, it also degrades the cell′s telomeres and activates stress responses and inflammation, thereby, accelerating biological aging.

Additionally, the researchers pointed out that a hypermetabolic state is a reason behind some of the symptoms, such as fatigue and exercise intolerance observed in people with mitochondrial diseases. 

(Source: https://www.tribuneindia.com/news/health/overactive-cell-metabolism-is-associated-with-biological-ageing-study-470116 )