Gut microbiota mediates the beneficial effects of exercise on autism-like behaviors.

Abstract

BACKGROUND: The gut-brain axis plays a critical role in autism spectrum disorder (ASD), but the mechanisms through which exercise modulates gut microbiota, short-chain fatty acids (SCFAs), and central neurotransmitters to ameliorate ASD-like behaviors remain unclear. This study aimed to investigate the effects of exercise on ASD-like behaviors, gut microbiota, and metabolism in a valproic acid (VPA)-induced ASD rat model and to validate these findings via fecal microbiota transplantation (FMT). METHODS: ASD rat models were established through prenatal exposure to VPA and divided into four groups: exercise (E_ASD), non-exercise (ASD), FMT, and sham FMT (sFMT). The E_ASD group underwent 6 weeks of voluntary wheel running, while the FMT group received fecal microbiota from the E_ASD group for 4 weeks. Behavioral assessments were conducted to evaluate cognitive and social functions. Fecal microbiota composition was analyzed via 16S rRNA sequencing, while SCFAs and neurotransmitters were measured using gas and liquid chromatography-mass spectrometry. RESULTS: Six weeks of voluntary exercise significantly alleviated ASD-like behaviors, particularly improving social interactions. Exercise also altered gut microbiota composition, increasing Limosilactobacillus and Lactobacillus while decreasing Allobaculum. Additionally, SCFAs and neurotransmitter levels in the prefrontal cortex were modulated. Notably, FMT from the exercise group replicated these behavioral and metabolic improvements in ASD rats. Exercise improves ASD-like behaviors by modulating gut microbiota, SCFAs, and neurotransmitter levels, and FMT offers further validation of these effects. CONCLUSION: These findings highlight exercise and FMT as promising strategies for alleviating ASD-related symptoms through gut-brain axis modulation.