CAN CALORIC RESTRICTION IMPROVE COGNITION IN AGING RATS?

ALTAMIRANO FG; PONCE IT; CASTRO-PASCUAL, I; FERRAMOLA, M.; DELGADO SM; ANZULOVICH AC; LACOSTE MG

MODALIDAD VIRTUAL

Congreso; IV REUNIÓN CONJUNTA DE LAS SOCIEDADES DE BIOLOGIA DE ARGENTINA; 2020

Caloric restriction (CR) consists of reducing daily calories intake without causing malnutrition. CR is the most effective non-pharmacologicalintervention in increasing longevity and reducing the effects of normal and pathological aging. Memory loss and cognitive impairment are one of themain features of aging and the effect of CR on these cognitive functions are still under study. Previous behavioral and molecular studies of our groupshowed that old animals had a low cognitive performance and loss of temporal expression of BDNF and TrkB, two proteins strongly linked tomemory and learning processes, in hippocampus. Furthermore, we also demonstrated that CR treatment in old animals restored these temporalpatterns of BDNF and TrkB in the hippocampus. Due to these antecedents, in the present work our objective was to evaluate if this restoration wepreviously observed at a molecular level is related to improvements in the cognitive performance of older animals under CR. Male Holtzman rats were separated into three experimental groups: young ad libitum (3-month-old, Y-AL group, N = 10), older ad libitum (22-month-old, O-AL group,N = 10), and older subjected to a 40% CR treatment during the last 3 months prior to the 22 months of age (O-CR group, N = 5). Cognitiveperformance was assessed using the Barnes Maze (BM) test for spatial learning and memory and the New Object Recognition (NOR) test forcontextual learning. In the BM test, we observed that the O-CR rats presented a shorter distance traveled on the platform, similar to Y-AL group. Wedid not find significant differences between O-CR and O-AL animals in the rest of the parameters analyzed with BM test (exploratory frequency ofthe target region, total exploratory activity, numbers of errors in reaching around the target hole, escape box latencies, percentage of exploration ofthe meta holes). In the NOR test, again we did not find significant differences between old animals and those subjected to CR. To date, the studiescarried out on the effects of CR on cognitive functions are inconclusive and depend on the used protocol. The effects of CR depend on its intensity,the period of life in which the treatment begins and its duration. Our studies are preliminary, with a first group of animals in CR (N = 5), thereforeincreasing the number of studied animals could provide more conclusive data. CR could be a non-pharmacological alternative for maintaining mentaland cognitive health during aging.