Brain–Gut–Microbiota Axis in Parkinson’s Disease: Gut Dysbiosis, Pathophysiological Mechanisms and Therapeutic Perspectives

Author

Rohini. N, Dr. S. Swarnalatha, Dr. J.Karthi, Vignesh M


Abstract

 Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by motor and non-motor manifestations. Although its major pathological features include degeneration of dopaminergic neurons and accumulation of abnormal alpha-synuclein, increasing research has examined the possible involvement of the gastrointestinal tract and gut microbiota. The brain–gut–microbiota axis represents a bidirectional communication network linking the gastrointestinal tract and central nervous system through neural, immune, endocrine and metabolic pathways. Alterations in gut microbial composition and function, commonly referred to as gut dysbiosis, have been reported in individuals with PD. Proposed mechanisms connecting intestinal changes with neurological processes include altered intestinal barrier function, immune activation, microbial metabolites, enteroendocrine signalling and alpha-synuclein-related processes. The body-first hypothesis suggests that disease-related pathology may begin outside the central nervous system in a subgroup of patients, whereas the brain-first hypothesis proposes an initial central nervous system origin. These concepts may help explain clinical heterogeneity but remain under investigation. Microbiota-directed interventions, including dietary approaches, probiotics, prebiotics and faecal microbiota transplantation, are being explored as potential therapeutic strategies. However, the current evidence does not establish gut dysbiosis as a direct cause of PD, and the clinical effectiveness of microbiota-targeted treatments remains uncertain. This review discusses the brain–gut–microbiota axis in PD, with emphasis on gut dysbiosis, proposed pathophysiological mechanisms, therapeutic perspectives and future research directions.



Keywords

Parkinson’s disease; gut microbiota; gut dysbiosis; brain–gut–microbiota axis; alpha-synuclein; neuroinflammation; intestinal barrier.



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References


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