Meeting Abstract

22.4  Jan. 5  Effect of food restriction on ageing in laboratory mice (Mus musculus) selected for high and low basal metabolic rate (BMR) BRZEK, P.*; KSIAZEK, A.; KONARZEWSKI, M.; Univ Bialystok PL; Univ Bialystok PL; Univ Bialystok PL brzek@uwb.edu.pl

The rate of aging is functionally related to the rate of metabolism. On the other hand, ageing can be delayed by caloric restriction, which implies a direct link between metabolism and reduced caloric intake. In our experiment, we examined the effect of 30% food restriction (FR) on mortality rate and physiological changes occurring between 6 and 12 months of age in laboratory mice divergently selected for high (H-BMR) or low (L-BMR) level of BMR. Mortality rate did not differ between control individuals of both lines. However, FR regimen decreased mortality rate in L-BMR, and increased in H-BMR line, as compared with control groups. Food restriction decreased swim-elicited peak metabolic rate in both lines, and BMR and post-swimming hypothermia in H-BMR line. However, BMR remained significantly higher in H-BMR than L-BMR line. The capacity to control oxidative stress (quantified as the total anti-oxidant enzymatic activity in blood serum) was similar in both lines and not affected by feeding regimen. Nevertheless, since H-BMR mice maintained higher metabolic rates throughout the whole experiment, we speculate that they were subject to more intense oxidative stress, which possibly contributed to their higher mortality. We conclude that our experiment demonstrated stronger effect of FR regimen on physiological traits of high BMR mice.