Caloric restriction restores temporal patterns of DNA methyltransferases, BDNF, TrkB and Bmal1 expression in the hippocampus of aged rats.

ALTAMIRANO, FERNANDO GABRIEL; CASTRO PASCUAL, IVANNA CARLA; FERRAMOLA, MARIANA LUCILA; DELGADO, SILVIA MARCELA; ANZULOVICH, ANA CECILIA; LACOSTE, MARÍA GABRIELA

Valparaíso

Simposio; XIV Latin American Symposium on Chronobiology (LASC); 2017

Caloric restriction (CR), the reduction of calories intake without causing malnutrition, is the only intervention that has shown to delay the onset and incidence of age-related diseases and, in elderly humans, to improve memory function. Previously, we observed circadian rhythms of BDNF, TrkB, Dnmts3a/3b and BMAL1 expression in the hippocampus of young rats; such oscillations were abolished in 22-m old animals. Here, we investigated temporal patterns of DNA methyltransferases (Dnmts), BDNF and TrkB expression as well as the circadian variation of the core clock protein, BMAL1, in the hippocampus of aged rats under CR. Holtzman male old rats were fed with a diet reduced by 40% in calories during the last 3 months prior to the 22 months of age. Animals were maintained under constant darkness conditions during 15 days before the experiment. Levels of Bdnf, TrkB, Dnmt1, Dnmt3a and Dnmt3b mRNA and BMAL1 protein were determined by RT-PCR and Western blot, respectively, in hippocampi samples isolated at 4h-intervals throughout a 24h period. In the present work, we observed CR restored the circadian rhythmicity of the studied parameters (Chronosfit: p