Volumetric alterations in the basal ganglia in autism Spectrum disorder: A systematic review

INTRODUCTION

Recent research indicates that some brain structures show alterations in conditions such as Autism Spectrum Disorder (ASD). Among them, are the basal ganglia that are involved in motor, cognitive and behavioral neural circuits.

OBJECTIVE

Review the literature that describes possible volumetric alterations in the basal ganglia of individuals with ASD and the impacts that these changes have on the severity of the condition.

METHODOLOGY

This systematic review was registered in the design and reported according to the PRISMA Items and registered in PROSPERO (CRD42023394787). The study analyzed data from published clinical, case-contemplate, and cohort trials. The following databases were consulted: PubMed, Embase, Scopus, and Cochrane Central Register of Controlled Trials, using the Medical Subject Titles (MeSH) "Autism Spectrum Disorder" and "Basal Ganglia". The last search was carried out on February 28, 2023.

RESULTS

Thirty-five eligible articles were collected, analyzed, and grouped according to the levels of alterations.

CONCLUSION

The present study showed important volumetric alterations in the basal ganglia in ASD. However, the examined studies have methodological weaknesses that do not allow generalization and correlation with ASD manifestations.

Physical exercise and flaxseed oil supplementation influence the glial plasticity in the rat hippocampus

Brain benefits from physical exercise associated with antioxidant supplements such as flaxseed oil. This low cost and simple association may improve hippocampal plasticity, which may work as a preventive and effective therapy in neuroprotection and neuroplasticity processes. This work evaluated the effects of physical exercise with flaxseed oil supplementation (Linum usitatissimum L.) in the hippocampus of Wistar rats. We separated male Wistar rats into four experimental groups: control group (sedentary), a sedentary group with a supplemental diet of flaxseed oil, a group under exercise program with flaxseed oil supplementation, and a group exclusively under exercise program. The swimming exercise consisted of a progressive 28‑day protocol followed by behavioral assessment, brain perfusion, microtomy, immunohistochemistry for glial fibrillary acidic protein (GFAP), cellular morphology, and optical density analysis. We used the ANOVA test with Tukey's post‑test for behavioral analysis. The exercise program with flaxseed oil supplementation was able to alter the GFAP expression in astrocytes in the CA1, CA3 and dentate gyrus regions of the hippocampus and modulate the behavioral aspects of memory and anxiety.

Neurobiological effects of forced swim exercise on the rodent hippocampus: a systematic review

Forced swimming is a common exercise method used for its low cost and easy management, as seen in studies with the hippocampus. Since it is applied for varied research purposes many protocols are available with diverse aspects of physical intensity, time and periodicity, which produces variable outcomes. In the present study, we performed a systematic review to stress the neurobiological effects of forced swim exercise on the rodent hippocampus. Behavior, antioxidant levels, neurotrophins and inflammatory markers were the main topics examined upon the swimming effects. Better results among these analyses were associated with forced exercise at moderate intensity with an adaptation period and the opposite for continuous exhausting exercises with no adaptation. On further consideration, a standard swimming protocol is necessary to reduce variability of results for each scenario investigated about the impact of the forced swimming on the hippocampus.

Forced swimming is a common exercise method used for its low cost and easy management, as seen in studies with the hippocampus. Since it is applied for varied research purposes many protocols are available with diverse aspects of physical intensity, time and periodicity, which produces variable outcomes. In the present study, we performed a systematic review to stress the neurobiological effects of forced swim exercise on the rodent hippocampus. Behavior, antioxidant levels, neurotrophins and inflammatory markers were the main topics examined upon the swimming effects. Better results among these analyses were associated with forced exercise at moderate intensity with an adaptation period and the opposite for continuous exhausting exercises with no adaptation. On further consideration, a standard swimming protocol is necessary to reduce variability of results for each scenario investigated about the impact of the forced swimming on the hippocampus.