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bioRxiv · 10.1101/2024.05.30.596620

Enriched environmental intervention mitigates hippocampal cellularity and behavioral disorders in maternal protein-restricted male rat offspring

Abstract

BackgroundGestational protein intake restriction induces long-lasting harmful outcomes in the offsprings organs and systems. AimsThis study sought to evaluate the effects of protein restriction during pregnancy and breastfeeding in 42-day-old male offspring on the structure of the hippocampus, behavior tests related to memory and emotions, and the influence of an enriched environment on these parameters. Results and DiscussionThe current study demonstrated that maternal protein restriction during neural development causes crucial morphological changes in the hippocampus, making the LP offspring vulnerable to specific neural disorders in adulthood. In addition, it supports the selfish brain theory, a paradigm that postulates the brain maintains its mass selfishly by reallocating resources from other body parts when faced with nutritional stress. However, the hippocampus cellularity pattern was profoundly altered, significantly reducing the number of neurons after the breastfeeding period. This may expand the understanding of nutritional stress affecting the brain areas constitution and its supposed effects on posterior behavioral disorders. Here, reciprocal data was observed between brain masses, changes in the hippocampus cell pattern, and decreased body mass in the LP progeny. In conclusion it was demonstrated that neuronal composition and structure profoundly modified by dietary restriction are surprisingly restored from primordial cells by exposure to the enriched environment. In addition, we must emphasize that although we have observed a significant reduction in the number of neurons after gestational and breastfeeding periods, we demonstrated for the first time a substantial reduction in the fear-reflecting behavior, which an enriched environment exposure may revert. The enriched environment also significantly modified the discrimination ratio, increasing the ability of both progenies to discriminate between novel and familiar objects in a short time associated with reverse abnormal hippocampus cell patterns. These findings underscore the potential for environmental interventions to mitigate the effects of early=life nutritional stress on brain development and behavior.

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BibTeXRIS

Gontijo, J. A. R., Boer, P. A., Grigoletti-Lima, G. B.. 2024-05-31. Enriched environmental intervention mitigates hippocampal cellularity and behavioral disorders in maternal protein-restricted male rat offspring. https://doi.org/10.1101/2024.05.30.596620

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