Aging modifies the circadian expression patterns of the neurotrophin BDNF and its receptor TrkB, in the rat hippocampus

LACOSTE, MARÍA GABRIELA; GOLINI, REBECA SUSANA; DEYURKA, NICOLÁS; DELGADO, SILVIA MARCELA; ANZULOVICH, ANA CECILIA

Tunuyán, Mendoza

Simposio; XII Latin American Symposium on Chronobiology; 2013

Most aging individuals show gradual impairment of cognitive capabilities associated with hippocampus alterations. BDNF and its receptor TrkB, play a critical role in the synaptic plasticity underlying the acquisition and/or consolidation of memory. Here, we investigated the expression of BDNF and TrkB throughout a 24h cycle, in the hippocampus of aged rats. Holtzman rats from young (3-months old) and aged (22-months old) groups were maintained under 12h-dark:12h-dark conditions (DD), during 10 days before the experiment. Regulatory regions of BDNF and TrkB genes were scanned for putative clock-responsive sites. Protein levels of the core clock component, BMAL1, were determined by Western Blot analysis, and BDNF and TrkB mRNA levels were determined by RT-PCR, in hippocampi isolated every 4 h during a 24h period. E-box (CANNTG) sites were found on regulatory regions of BDNF and TrkB genes. We observed endogenous-driven BDNF (p