Fecal Microbiota Transplantation Is Effective for the Treatment of Partially Treated Clostridioides difficile Infection

Unveiling the hidden culprit: How the brain-gut axis fuels neuroinflammation in ischemic stroke

Background

The brain-gut axis represents a bidirectional communication network between the gut microbiome and the central nervous system that plays an important role in homeostasis. Compelling evidence now confirms that ischemic stroke disrupts this delicate balance by inducing gut dysbiosis.

Methods

A comprehensive literature search was performed in PubMed, Web of Science, and Google Scholar for articles published between January 2000 and January 2023 using relevant keywords. Studies were limited to English and included original studies, literature, and systematic reviewers from peer-reviewed journals which discussed gut microbiota composition in models/subjects with ischemic stroke or assessed stroke impact on gut microbiota. Comments, meeting abstracts, and case reports were excluded. From the 80 relevant articles, we summarized key findings related to gut microbiota changes after stroke and their association with stroke outcomes.

Results

Emerging preclinical evidence underscores the pivotal role of the gut microbiome in glial cell development and function. Germ-free models exhibit compromised microglial activation and impaired cellular debris clearance, exacerbating tissue damage following ischemic stroke. Targeted interventions, including prebiotics, probiotics, and fecal microbiota transplantation, have demonstrated efficacy in rescuing glial phenotypes in preclinical stroke models. Beyond its local effects, the gut microbiome significantly influences systemic immunity. Ischemic stroke polarizes pro-inflammatory phenotypes of neutrophils and T cells, amplifying neurovascular inflammation. Microbiota manipulation modulates leukocyte trafficking and metabolic signaling, offering potential avenues to mitigate infarct pathology.

Conclusion

Our review demonstrates that in preclinical stroke models, modulating the lipopolysaccharide, short-chain fatty acid, and trimethylamine N-oxide pathways through the gut-brain axis reduces infarct sizes and edema and improves functional recovery after ischemic stroke. Further exploration of this important axis may unveil additional adjunctive stroke therapies by elucidating the complex interplay between the microbiome and the brain. Rigorously controlled clinical studies are now warranted to translate these promising preclinical findings and investigate whether manipulating the microbiome-brain relationship can help improve outcomes for stroke patients. Overall, continued research on the gut-brain axis holds exciting possibilities for developing novel treatment strategies that may enhance recovery after stroke.

Therapeutics involved in managing initial and recurrent Clostridium difficile infection: An updated literature review

Clostridium difficile infection (CDI) has been increasing due to the effect of recurrent hospitalizations. The use of antibiotics has been shown to alter the gut microbiome and lead to CDIs. The treatment is limited to three major antibiotics; however, the incidence of recurrent CDIs has been increasing and drug resistance is a major concern. This aspect is a growing concern in modern medicine especially in the elderly population, critical care patients, and immunocompromised individuals who are at high risk of developing CDIs. Clostridium difficile can lead to various complications including septic shock and fulminant colitis that could prove to be lethal in these patients. Newer modalities of treatment have been developed including bezlotoxumab, a monoclonal antibody and fecal microbiota transplant. There have been studies showing asymptomatic carriers and drug resistance posing a major threat to the healthcare system. Newer treatment options are being studied to treat and prevent CDIs. This review will provide an insight into the current treatment modalities, prevention and newer modalities of treatment and challenges faced in the treatment of CDIs.

A Keystone Gut Bacterium Christensenella minuta-A Potential Biotherapeutic Agent for Obesity and Associated Metabolic Diseases

A new next-generation probiotic, Christensenella minuta was first discovered in 2012 from healthy human stool and described under the phylum Firmicutes. C. minuta is a subdominant commensal bacterium with highly heritable properties that exhibits mutual interactions with other heritable microbiomes, and its relative abundance is positively correlated with the lean host phenotype associated with a low BMI index. It has been the subject of numerous studies, owing to its potential health benefits. This article reviews the evidence from various studies of C. minuta interventions using animal models for managing metabolic diseases, such as obesity, inflammatory bowel disease, and type 2 diabetes, characterized by gut microbiota dysbiosis and disruption of host metabolism. Notably, more studies have presented the complex interaction between C. minuta and host metabolism when it comes to metabolic health. Therefore, C. minuta could be a potential candidate for innovative microbiome-based biotherapy via fecal microbiota transplantation or oral administration. However, the detailed underlying mechanism of action requires further investigation.