Exercise-induced reversal of age-related declines of oxidative reactions, mitochondrial yield, and flavins in skeletal muscle of the rat.
The ability of gastrocnemius muscle homogenates to catalyze the oxidation of succinate, glutamate + malate, pyruvate + malate, palmitoyl-coenzyme A, decanoylcarnitine and palmitoylcarnitine in the presence of ADP decreased by approximately 32% in sedentary male Sprague-Dawley rats between the ages of 9 and 25 months. Following 21 weeks of treadmill training (running), such homogenates from 25-month-old animals catalyzed oxidations 55% more rapidly than those from 25-month-old sedentary rats, and 17% faster than those from 9-month-old sedentary rats. Total and peptide-bound flavin of gastrocnemius muscles also declined between 9 and 25 months of age and were elevated in the 25-month-old endurance trained rats to levels greater than both 9- and 25-month-old sedentary animals. The yield of protein in the mitochondrial fraction from the quadriceps femoris muscle decreased between 9 and 25 months and was restored to the 9-month level by endurance training. The kinetic characteristics of the isolated mitochondria were not influenced by age or exercise. These data indicate that 2-year-old rats retain the capacity to increase skeletal muscle oxidative capacity and mitochondrial population density in response to endurance training.
D000375:Aging; D000818:Animals; D005415:Flavins / Q000378:metabolism; D008297:Male; D008931:Mitochondria, Muscle / Q000378:metabolism; D009124:Muscle Proteins / Q000378:metabolism; D009132:Muscles / Q000378:metabolism*; D009929:Organ Size; D010084:Oxidation-Reduction; D005082:Physical Exertion; D051381:Rats; D011919:Rats, Inbred Strains
D005415:Flavins; D009124:Muscle Proteins