Ketogenic Diet, Caloric Restriction And Intermittent Fasting Increase The Mitochondrial Activity In Aged Rats

Abstract

Objective: Studying the effect of multiple dietary strategies on mitochondrial activity of aged rats. Background: Healthy aging may be achieved by intermittent fasting, caloric restriction or ketogenic diet regimens. Material and methods: Thirty-two male Wistar rats, 20-22-week-old, were randomized into four equal groups: control, ketogenic diet (KD), caloric restriction (CR) and intermittent fasting (IF) groups. After 8 weeks, rats were weighed, and subjected for measurement of systolic blood pressure (SBP) using a rat-tail sphygmomanometer, and neurobehavioral assessment via open field examination. Then, fasting retro-orbital blood samples were collected to measure free fatty acids (FFA), liver and kidney function tests and lipid profile. HOMA-IR was calculated from fasting blood glucose and serum insulin levels. Citrate synthase activity, as an index of mitochondrial activity of the brain, heart and liver, was measured in tissue homogenates. Results: A reduction of the body weight was observed in KD and IF groups when compared with control group, while no body weight reduction occurred with CR group. Significant improvement of SBP and increase in FFA and citrate synthase activity were observed in all the dietary strategy groups versus control one, with dyslipidemia produced by KD. ALT and serum creatinine of KD were increased compared to those of C, CR and IF groups. KD and IF groups showed increased number of the squares crossed in open field test. Conclusion: Ketogenic diet, caloric restriction and intermittent fasting increased mitochondrial activity in the aged rats.