Role of gut microbiota in ischemic stroke: A narrative review of human and animal studies.

The high incidence, mortality, and disability associated with ischemic stroke pose a significant threat to human health. The intestinal microbiota significantly influences the onset, progression, and prognosis of ischemic stroke. Gut flora plays a pivotal role in brain-gut interactions. The reflection of changes in the gut and brain caused by gut microbes facilitates the investigation of early warning biomarkers and potential therapeutic targets for ischemic stroke. In this narrative review of the relationship between gut microbiota and ischemic stroke, we primarily discuss three topics, grounded in real-world human and animal studies. First, we examined the relationship between ischemic stroke and intestinal microbiota and its metabolites, delineate the overall characteristics of intestinal microbiota dysregulation in ischemic stroke, and assess the potential clinical value, prevailing research controversies, and unique phenomena of intestinal microbiota metabolites such as trimethylamine N-oxide and short-chain fatty acids in ischemic stroke. Second, we explored the potential communication pathways between intestinal flora and ischemic stroke based on the brain-gut axis, encompassing metabolic pathways, immune pathways, and neural pathways. Finally, we encapsulated the factors influencing the severity of ischemic stroke via intestinal flora, the pharmacological and nonpharmacological interventions that modulate intestinal flora in treating ischemic stroke, and the current research landscape of intestinal flora in the context of ischemic stroke sequelae.