Are neuromodulation interventions associated with changes in the gut microbiota? A systematic review

Area of Science:

• Neuroscience
• Microbiology
• Gastroenterology

Background:

• The microbiota-gut-brain axis (MGBA) describes bidirectional communication between the brain and gut microbes, implicated in health and disease.
• Research has primarily focused on the microbiota-to-brain direction, with limited understanding of how the brain influences the gut microbiome.

Approach:

• A systematic review was conducted to investigate the impact of neuromodulation techniques on gut microbiota composition.
• Searches in PsycINFO and MEDLINE identified clinical and preclinical studies evaluating deep brain stimulation, ECT, rTMS, tDCS, and VNS.
• Seven studies were included, analyzing changes in gut microbiota before and after intervention or between active and control groups.

Key Points:

• Neuromodulation interventions were associated with alterations in relative bacterial abundances within the gut microbiome.
• No significant associations were found between neuromodulation and changes in gut microbial alpha-diversity or beta-diversity.
• The identified studies suggest moderate impacts of neuromodulation on the gut microbiome.

Conclusions:

• Current findings indicate a potential link between neuromodulation and gut microbiota changes, primarily affecting bacterial composition.
• The limited number, varying quality, and heterogeneity of studies render current findings inconclusive.
• Further research is necessary to definitively establish the influence of neuromodulation on the gut microbiota and elucidate underlying mechanisms.