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Early exercise induces long-lasting morphological changes in cortical and hippocampal neurons throughout of a sedentary period of rats.

ABSTRACT: Life experiences at early ages, such as physical activity in childhood and adolescence, can result in long-lasting brain effects able to reduce future risk of brain disorders and to enhance lifelong brain functions. However, how early physical exercise promotes these effects remains unclear. A possible hypothesis is that physical exercise increases the expression of neurotrophic factors and stimulates neuronal growth, resulting in a neural reserve to be used at later ages. Basing our study on this hypothesis, we evaluated the absolute number and morphology of neuronal cells, as well as the expression of growth, proliferation and survival proteins (BDNF, Akt, mTOR, p70S6K, ERK and CREB) in the cerebral cortex and hippocampal formation throughout of a sedentary period of rats who were physically active during youth. To do this, male Wistar rats were submitted to an aerobic exercise protocol from the 21st to the 60th postnatal days (P21-P60), and evaluated at 0 (P60), 30 (P90) and 60 (P120) days after the last exercise session. Results showed that juvenile exercise increased, and maintained elevated, the number of cortical and hippocampal neuronal cells and dendritic arborization, when evaluated at the above post-exercise ages. Hippocampal BDNF levels and cortical mTOR expression were found to be increased at P60, but were restored to control levels at P90 and P120. Overall, these findings indicate that, despite the short-term effects on growth and survival proteins, early exercise induces long-lasting morphological changes in cortical and hippocampal neurons even during a sedentary period of rats.

SUBMITTER: Serra FT

PROVIDER: S-EPMC6757043 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Early exercise induces long-lasting morphological changes in cortical and hippocampal neurons throughout of a sedentary period of rats.

Serra Fernando Tadeu FT Carvalho Andrea Dominguez AD Araujo Bruno Henrique Silva BHS Torres Laila Brito LB Cardoso Fabrizio Dos Santos FDS Henrique Jéssica Salles JS Placencia Eduardo Varejão Díaz EVD Lent Roberto R Gomez-Pinilla Fernando F Arida Ricardo Mario RM Gomes da Silva Sérgio S

Scientific reports 20190923 1

Life experiences at early ages, such as physical activity in childhood and adolescence, can result in long-lasting brain effects able to reduce future risk of brain disorders and to enhance lifelong brain functions. However, how early physical exercise promotes these effects remains unclear. A possible hypothesis is that physical exercise increases the expression of neurotrophic factors and stimulates neuronal growth, resulting in a neural reserve to be used at later ages. Basing our study on th ...[more]

PMID: 31548605

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Early exercise induces long-lasting morphological changes in cortical and hippocampal neurons throughout of a sedentary period of rats.

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Early exercise induces long-lasting morphological changes in cortical and hippocampal neurons throughout of a sedentary period of rats.

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