Fiber2026-08

Gut Microbiota and Ischemic Stroke: From Pre-Stroke Dysbiosis and Acute-Phase Changes to Therapeutic Applications.

Weng Ruihui, Dong Gaolei, Tang Jianxin, Zhao Yu — Brain and behavior

Summary

This review explores the strong connection between our gut bacteria and ischemic stroke, a type of stroke caused by blood clots. It highlights how an imbalance in gut microbes can increase stroke risk and how these microbes change during and after a stroke. The paper also discusses potential future treatments that target gut bacteria to help prevent or recover from stroke.

AI-generated summary — read the original

Key points

An unhealthy balance of gut bacteria may increase the risk of ischemic stroke.
Stroke can cause further negative changes in the gut microbiome, potentially affecting recovery.
Gut bacteria influence stroke outcomes through various pathways, including inflammation and immune responses.
Future treatments targeting gut bacteria, such as probiotics or dietary fiber, show promise but need more research.

What the study looked at

This comprehensive review aimed to understand the complex relationship between gut bacteria and ischemic stroke. Specifically, it explored how an imbalance in gut microbes might contribute to stroke risk, how the gut microbiome changes during and after a stroke, and what potential therapies could target these bacteria. Researchers conducted a thorough review of existing scientific literature, synthesizing current evidence on how the gut and brain communicate, the role of individual factors, and potential interventions for ischemic stroke. The review found that an unhealthy gut microbiome can act as a risk factor for stroke by promoting inflammation and blood clot formation. After a stroke, there's often a decrease in beneficial bacteria and an increase in harmful ones, which can worsen complications like cognitive issues or depression. While promising interventions like probiotics and dietary fiber have shown some benefits in early studies, more robust human trials are needed to confirm their effectiveness.

Dietary takeaway

This review suggests that maintaining a healthy gut microbiome could be an important strategy for stroke prevention and recovery. Including plenty of fiber-rich foods like fruits, vegetables, whole grains, and legumes in your daily diet can help nourish beneficial gut bacteria. However, remember that this is a review of existing studies, and while promising, more research is needed to definitively establish specific dietary recommendations for stroke.

Abstract

PURPOSE: Ischemic stroke poses a major global health burden, and growing evidence points to the microbiota-gut-brain axis as an important contributor to stroke pathophysiology and recovery. The purpose of this review is to summarize current knowledge on bidirectional gut-brain communication in stroke, establishing gut dysbiosis as an upstream risk factor for stroke onset and examining microbiota dynamics across acute and chronic phases. METHOD: A comprehensive review of the current literature was conducted to synthesize existing evidence on the mechanisms of gut-brain communication, the influence of host factors, post-stroke complications, and candidate therapeutic interventions targeting the MGBA in ischemic stroke. FINDING: Gut dysbiosis acts as a risk factor for stroke through TMAO-mediated atherothrombosis, systemic inflammatory priming, and comorbidity-associated dysbiotic pre-conditioning. Following a stroke, dysbiosis is characterized by a depletion of short-chain fatty acid (SCFA)-producing taxa and an expansion of pro-inflammatory bacteria, particularly Proteobacteria and Enterobacteriaceae. Host factors (age, sex, genetics, and comorbidities) shape microbiota signatures and influence outcomes. Furthermore, post-stroke complications-including cognitive impairment, depression, stroke-associated pneumonia, and gastrointestinal dysfunction-are intimately linked to persistent dysbiosis. Mechanistically, the gut microbiota modulates stroke outcomes through immune regulation, metabolite signaling, blood-brain barrier integrity, and vagal pathways. Candidate therapeutic interventions (probiotics/prebiotics, fecal microbiota transplantation, SCFA supplementation, traditional Chinese medicine, and neuromodulation) demonstrate promising neuroprotective and recovery-enhancing effects, predominantly in preclinical models. CONCLUSION: While targeted interventions like probiotics and dietary fiber supplementation have shown modest benefits in small clinical trials, human clinical evidence remains largely preliminary. The translation of FMT, SCFA supplementation, and neuromodulatory approaches to clinical practice requires validation through rigorous, adequately powered randomized controlled trials. Future precision microbiome medicine demands individualized profiling and phenotype-specific interventions to establish microbiota-targeted strategies as viable adjunctive stroke therapies.

View on PubMed →DOI: 10.1002/brb3.71547