Calorie Restriction: The Elixir of Youth for Kidneys and Testicles?

Abstract

Objective: Reactive oxygen species that accumulate during aging can cause oxidative stress in kidney and testicular tissues, contributing to the progression of chronic kidney disease and to male infertility. Caloric restriction (CR) is considered the most effective non-pharmacological method to promote healthy aging through multiple mechanisms, including modulation of oxidative stress. This study aimed to investigate the effects of short-term CR on kidney and testicular tissues during aging.

Methods: Twenty-eight rats were divided into four groups: young control, young CR, old control, and old CR. Control groups were fed ad libitum, whereas CR groups received approximately one-third of their daily caloric intake. After 10 weeks, blood parameters [creatinine (Cre), blood urea nitrogen, uric acid (UA), testosterone levels], oxidative stress markers [malondialdehyde (MDA) and glutathione (GSH)], and histological changes were analyzed.

Results: Aging was associated with increased body and kidney weights and a reduced testicular index p < 0.005. CR reduced body and kidney weights and increased kidney and testicular indices (p <0.005). Renal function markers (Cre and UA) increased with age but were significantly reduced by CR (p <0.005). Aging increased MDA levels and decreased GSH levels in both renal and testicular tissues. Aging increased inflammatory cell infiltration and fibrosis in the kidney and testicular tissues, whereas CR significantly reduced the fibrosis percentage in aged rats.

Conclusion: Short-term CR may alleviate structural and functional impairments in the kidney and testis during aging by reducing oxidative stress.