The elderly experience profound systemic responses after stroke, contributing to higher mortality and more severe long-term disability. Recent studies have revealed that the composition of the gut microbiome can influence stroke outcomes.

This study aimed to determine whether restoring youthful gut microbiota post stroke, helps in the recovery in aged subjects. The gut microbiome was altered via young fecal transplant gavage in aged mice after the induced stroke. Fecal transplant gavage was performed three days after middle cerebral artery occlusion using aged biome or young donor biome. This  study is first to suggest that poor stroke recovery in aged mice can be reversed via poststroke bacteriotherapy following the replenishment of youthful gut microbiome via microbial, immunologic, and metabolomic modulation profiles in the host. Our study strongly supports the idea that targeting bottom-up signaling can enhance post-stroke recovery in aged subjects.

In conclusion, the results indicate that rejuvenation of gut microbiome post-stroke in aged mice enhances host immunity and dramatically improves gut integrity. The beneficial effects of SCFA/probiotics may directly benefit other acute neuronal injury models. Hence, this study provides the first direct experimental evidence that microbiota composition can be therapeutically exploited to improve recovery after stroke.