Fecal microbiota transplantation alleviates neuronal Apoptosis, necroptosis and reactive microglia activation after ischemic stroke.

Objective: This study aims to delve into the mechanisms underlying the improvement of neurological function in rats with ischemic stroke through fecal microbiota transplantation.

Methods: A total of fifty male Sprague-Dawley rats were categorized into four groups: Sham, MCAO, MCAO+vehicle and FMT. We assessed behavioral and pathological alterations in the rats using modified neurological function scoring and TTC staining.Additionally, Western blot and immunofluorescence were used to detect the expression levels of Apoptotic and Necroptosis markers in neurons of ischemic brain tissue, and immunofluorescence was used to analyze the degree of activation of microglia.

Results: FMT group exhibited a decline in neurological function score compared to the MCAO and MCAO + vehicle group, accompanied by a reduction in infarct volume (P < 0.05). Relative to the SHAM group, the MCAO group displayed a significant increase in the expression levels of necroptosis-related proteins Phospho-RIP1, Phospho-RIP3, Phospho-MLKL, apoptotic proteins Bax and Cleaved caspase-3, and the iNOS positive microglia in ischemic brain tissue, while Bcl-2 expression was notably decreased (P < 0.05).Conversely, compared to the MCAO + vehicle group, the FMT group showed decreased expression levels of Phospho-RIP1, Phospho-RIP3, Phospho-MLKL, Bax, Cleaved caspase-3, and iNOS-positive microglia, while the expression of Bcl-2 was increased.

Conclusion: Fecal microbiota transplantation offers a promising approach to improving neurological function in rats with ischemic stroke by inhibiting neuronal apoptosis, necroptosis, and the polarization of inflammatory microglial cells.