Meeting Abstract
32.2 Jan. 5 Testing the “free radical theory of aging” hypothesis: physiological differences in long lived and short lived Colubrid snakes ROBERT, K.A*; BRONIKOWSKI, A.M; Iowa State University; Iowa State University krobert@iastate.edu
We test the �free radical theory of aging� using 6 species of Colubrid snakes (numerous, widely distributed, non-venomous snakes of the family Colubridae) that exhibit long (>15 years) or short (<10 years) life spans. We measured whole animal metabolic rate (oxygen consumption V.O2), locomotor performance (as a measure of fitness and survival), cellular metabolic rate (mitochondrial oxygen consumption) and oxidative stress potential (hydrogen peroxide production by mitochondria). The general assumption is that species with shorter life spans grow quickly and reproduce at a younger age, therefore investing heavily into growth and reproduction and less into somatic maintenance, performance and survival, whereas longer lived species invest heavily in somatic maintenance, performance and survival and less into growth and reproduction, hence grow slower and reproduce later. We hypothesized that longer lived species will exhibit: reduced metabolic rates, increased physical performance (fitness/survival), and efficient mitochondria that produce reduced amounts of oxidants in comparison to short lived species. We found that longer lived Colubrid snakes have greater locomotor performance and reduced hydrogen peroxide production than short lived species, while whole animal metabolic rates and mitochondrial efficiency did not differ with lifespan. Whole animal metabolic rates do not support the rate of living theory model and do not correlate directly with longevity. However, our results support the free radical theory of aging and hence, the rate of living theory at the cellular level, to provide some explanation for the differences in lifespan among the species examined. We present the first measures testing the free radical theory of aging using reptilian species as a model organism.
