Strawberry consumption improves aging-associated impairments, mitochondrial biogenesis and functionality through the AMP-activated protein kinase signaling cascade

•Strawberry consumption counteracts oxidative stress in old rats.•Strawberry consumption ameliorates endogenous antioxidant defences in old rats.•Strawberry consumption improves mitochondrial biomass and functionality in old rats.•Strawberry consumption activates AMPK signaling pathway in old rats.•AMPK can be a new valuable target for improving aging condition. Dietary polyphenols have been recently proposed as activators of the AMP-activated protein kinase (AMPK) signaling pathway and this fact might explain the relationship between the consumption of polyphenol-rich foods and the slowdown of the progression of aging. In the present work, the effects of strawberry consumption were evaluated on biomarkers of oxidative damage and on aging-associated reductions in mitochondrial function and biogenesis for 8weeks in old rats. Strawberry supplementation increased antioxidant enzyme activities, mitochondrial biomass and functionality, and decreased intracellular ROS levels and biomarkers of protein, lipid and DNA damage (P