The Gut-Brain Axis: Neuroenteric Modulation and Microbial Pathogenesis in Neurodegenerative Diseases

Abstract

In this study, we investigate the bidirectional communication network between the gastrointestinal tract and the central nervous system, widely recognized as the gut-brain axis. Neurodegenerative disorders, particularly Parkinson’s disease and Alzheimer’s disease, have traditionally been characterized through a neuro-centric lens. However, our emerging framework shifts this paradigm by examining how pathological configurations originate within the enteric ecosystem. We analyze the mechanisms through which intestinal dysbiosis initiates systemic inflammatory cascades, compromises biological barriers, and triggers the misfolding of critical proteins. By tracking the transmission pathways along the vagus nerve and evaluating the biochemical roles of microbial metabolites, we establish a robust correlation between gut health and neurodegeneration. Our research synthesized extensive metadata to map specific bacterial taxonomic shifts and their downstream neurological consequences. The findings emphasize that structural changes in the gut microbiome significantly precede classic motor and cognitive symptoms. Consequently, we propose that modifying the enteric microenvironment represents a viable, highly accessible therapeutic window for disease-modifying interventions. Ultimately, this article provides a consolidated molecular baseline to guide next-generation clinical trials focusing on microbiome-targeted therapeutics, fecal microbiota transplantation, and neuroprotective postbiotic protocols.