The role of the gut microbiome in mediating neuroinflammation in immune-based neurological disorders

The gut microbiome can influence brain health by modulating neuroinflammation through various mechanisms, including immune regulation, the production of metabolites that affect neural function, gut and blood-brain barrier integrity, upstream effects via the vagus nerve, upstream migration of gut-resident lymphocytes to the brain, bile acid signalling, and endocrine activity. Changes in gut microbiota have been observed in demyelinating conditions, autoimmune encephalitis, and epilepsy. Gut microbiota composition changes can affect neuroinflammation, disease progression, and treatment outcomes. Advances in microbiome research have improved the potential for clinical translation of findings; but limitations persist, driven by the largely correlational nature of clinical studies and the complexity of microbiome sequencing and interpretation. At present, only the ketogenic diet is routinely recommended by clinicians, whereas other microbiome-based interventions remain investigational. Multiple strategies for manipulating the gut microbiome, including dietary changes, prebiotics, probiotics, postbiotics, and faecal microbiota transplantation, might be used as disease-modifying therapies in the future.