Interplay between corticosterone and BDNF signaling in animals fed with high fat diet and exposed to chronic stress

VILÁ, MB; PAULAZZO, A; WALD, MR; GENARO, AM; RUBINSTEIN, MR

CABA

Congreso; REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE FISIOLOGÍA. 2023; 2023

SOCIEDAD ARGENTINA DE FISIOLOGÍA

Introduction: Adaptation to stress requires adjustments through interrelations between the hypothalamus–pituitary–adrenal axis (HPA), sympathetic efferent pathways and chemical messengers (like hormones and neurotrophins). Prolonged stress can produce severe consequences that affect the hippocampus, leading to behavioral alterations. On the other hand, stress exposure and poor eating habits are interconnected to each other, leading to an increased in obesity and becoming a serious health problem. We have previously shown that a high fat diet (HFD) increased body weight, but chronic stress exposure (CS) induced a decrease in body weight. Objectives: the aim of the present work was to study the effect of HFD and CS exposure oncognitive performance and to investigate the participation of the HPA axis, sympathetic nervous system and neurotrophins in hippocampus in C57Bl/6J male mice. Methods: C57Bl/6J male mice were fed a standard diet (SD) or a HFD. After eight weeks, some animals were also exposed to CS by the application of aleatory and unpredictable stressors for 20 more weeks. This resulted in 4 groups of animals: SD, SD + CS, HFD and HFD + CS. To study the cognitive performance, the spontaneous alternation in the Y-maze task and Barnes maze task were performed. Results: In the Y-maze task CS, HFD and HFD + CS groups showed a decreased the spontaneous alternation. In Barnes maze task, the results showed that the percentage of time spent in the target quadrant was similar for all experimental groups, but the latency to find the target hole was increased in HFD +CSgroup. Plasma corticosterone levels showed an increase in HFD group. In contrast, in HFD + CS group this increase was impaired. Glucocorticoid receptor expression in hippocampus was increased in HFD and HFD + CS and similar results were found for beta2-adrenergic receptor. A decreased in hippocampal BDNF expression was found in HFD and HFD + CS groups measured byqPCR. Conclusion: These results show an interplay between corticosterone, BDNF and beta2-adrenergic signaling in animals fed with HFD and HFD + CMS. More studies are necessary to elucidate the mechanism involved.