Gut microbiome and neurodegenerative disorders: therapeutic Implications

The gut microbiome, home to 100 trillion microorganisms, and its influence on brain health and disease via the gut-brain axis has encouraged interdisciplinary studies. The gut-brain axis is the two-way communication network connecting the gut microbiome to the central nervous system. Gut microbes produce neurotransmitters such as serotonin and gamma-aminobutyric acid, which can impact mood and cognitive function. The microbial imbalance can lead to systemic inflammation, which may contribute to neuroinflammation and further cause neurodegeneration. Additionally, it modulates immune responses and results in autoimmune disorders. Every day, new and progressive findings are surfacing related to microbiota-mediated neurodegenerative disorders, their mechanistic approach, and different therapeutic approaches to ameliorate these conditions. In this review, we aim to unfold the intricate relationship of the microbiota-gut-brain axis to overlay a better understanding of the microbiota-mediated pathogenesis of neurodegenerative disorders, popularly known as Alzheimer’s and Parkinson’s disease, including amyotrophic lateral sclerosis, multiple sclerosis, and Huntington’s disease. Aging accelerates neurodegeneration by modulating microbial composition, altering metabolic processes and immune functions. Moreover, possible therapeutic strategies such as the use of probiotics, prebiotics, synbiotics and various dietary modulations to ameliorate neurodegenerative conditions have been outlined in both preclinical and clinical studies. As the gut microbiome is highly individualistic, designing personalized prebiotic or probiotic formulations according to each person's microbiome profile is a future challenge. More research is needed to fully understand how the gut microbiota influences neurodegenerative processes at a mechanistic level. The long-term effects of microbiome-based interventions on neurodegenerative diseases need to be thoroughly investigated to establish their safety and efficacy. Keywords: Gut microbiota, gut-brain axis, neurodegenerative disorders, probiotics, prebiotics, aging