Systematic analysis of the relationship between intestinal microbiota and neurological disorders: emerging perspective in neurogastroenterology

Abstract

By the complex gut-brain axis, the gut microbiota (GM) has a critical role in neurological function. The complex link between several neurological illnesses and the gut microbiota (GM) is examined in this comprehensive study. Strong evidence has been found, based on a review of the literature from 2019 to 2024, connecting GM dysbiosis to the etiology and development of conditions such as epilepsy, multiple sclerosis, Alzheimer's disease, autism spectrum disorder, stroke, and amyotrophic lateral sclerosis (ALS). In these cases, GM changes increase disease severity, interfere with immune responses, and worsen neuroinflammation. In particular, dysbiosis affects the prevalence of autoimmune encephalomyelitis in MS and adds to motor impairment and gastrointestinal symptoms in PD. Via pro-inflammatory microorganisms, dysregulated GM in AD exacerbates neurodegeneration. Moreover, the gut-brain axis influences emotion, behavior, and cognition, all of which are impacted by the development of ASD. In epilepsy, GM dysbiosis affects inflammatory responses and seizure frequency; in ALS, it leads to neuroinflammation and motor neuron degeneration. Notwithstanding noteworthy discoveries, the dearth of randomized controlled trials presents obstacles, requiring more mechanistic clarification and investigation of microbiota-targeted treatments for neurological disorders.