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G.P. Holloway et al., “Age-associated impairments in mitochondrial ADP sensitivity contribute to redox stress in senescent human skeletal muscle,” Cell Rep, 22:2837–48, 2018.
The electron transport chain within mitochondria helps produce energy in the form of ATP through redox reactions, generating reactive oxygen species (ROS) in the process. In rodents, rising levels of ROS have been linked to aging in mice, Graham Holloway of the University of Guelph in Canada notes. In a recent study, his team used biopsies from a quadriceps muscle to test whether the association held up in humans.
The researchers grew human muscle fibers from biopsies in culture in the presence of varying amounts of the ATP precursor ADP and measured the amounts of oxygen used up and hydrogen peroxide (an ROS) released in mitochondria.
In healthy young adults, optimally functioning ADP ferries electrons quickly through the final step of cellular respiration, ...
