Atividade física precoce e a hipótese de reserva neural: análise dos níveis corticais e hipocampais de fator neurotrófico derivado do encéfalo (BDNF), de hormônio adrenocorticotrófico (ACTH) e de corticoesterona ao longo da vida sedentária de ratos que foram fisicamente ativos na adolescência

• Ano de defesa: 2018
• Autor(a) principal: Carvalho, Andrea Dominguez [UNIFESP]
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de São Paulo (UNIFESP)
• Palavras-chave em Português: Physical activity; Neural reserve; BDNF; Stress hormones; Atividade física; Reserva neural; Hormônios de estresse
• Link de acesso: https://sucupira.capes.gov.br/sucupira/public/consultas/coleta/trabalhoConclusao/viewTrabalhoConclusao.jsf?popup=true&id_trabalho=6733037; https://repositorio.unifesp.br/handle/11600/52191

Purpose: There are reports that life experiences at early ages such as physical activity in childhood and adolescence can reduce the future risk of brain disorders and enhance lifelong brain functions. However how early physical activity promotes such effects are not well understood. A possible explanation is that physical exercise can stimulate neuronal growth, resulting in a neural reserve which could be extracted throughout the life course. Based in this hypothesis, the present study was designed to investigate the neural reserve induced by early physical activity. To do this, we evaluated the cortical and hippocampal levels of BDNF, ACTH and corticosterone during the aging course of rats submitted to physical exercise during adolescent period. Methods: Thirtyfive male Wistar rats were distributed into exercise (EX, n=18) and control (CTL, n=17) groups. Rats from EX group were submitted to an aerobic exercise program during the 21st and 60th postnatal day (P21P60). Afterward, cortical and hippocampal levels of BDNF, ACTH and corticosterone from the EX and CTL groups were investigated at different life stages: 0 (P60), 30 (P90), 60 (P120) and 90 (P150) days after last exercise session. The BDNF, ACTH and corticosterone levels were quantified by mean of Luminex xMAP system (MAGPIX technology). Results: No change was detected in the cortical and hippocampal levels of ACTH and corticosterone (p > 0.05). After the last physical training session (at P60), it was noted a significant increase of hippocampal BDNF (p < 0.05). However, this effect induced by early exercise was not maintained throughout the sedentary life of rats (ie, BDNF levels returned to control levels at P90 and P120). Conclusion: Our results indicate that changes in hippocampal BDNF levels may occur in rats exercised in youth, especially at P60. However, no persistent and longlasting effect of early physical exercise, which could be related to the neural reserve, was found in this study.