Is the Gut Microbiome the Answer to All Our Problems? Critical Review

Abstract: 

This paper is a review of the bidirectional relationship between the gut microbiome and neurological diseases, focusing on Parkinson’s disease (PD), Alzheimer’s disease (AD), Huntington’s disease (HD), and the impact of traumatic brain injury (TBI), cerebral palsy (CP), and stroke on gut microbiota. It examines how gut dysbiosis, or an imbalance between harmful and beneficial bacteria, contributes to the progression of neurodegenerative diseases. The review finds that pro-inflammatory bacteria such as Proteobacteria, Bacteroides, and Desulfovibrionaceae exacerbate neuroinflammation, accelerating disease symptoms in PD, AD, and HD. In contrast, beneficial bacteria like Firmicutes, Clostridiales, and Lachnospiraceae help slow disease progression by producing anti-inflammatory short-chain fatty acids (SCFAs) that protect the gut-brain axis. Dietary factors, including omega-3-rich foods, antioxidants, and fermented products, are identified as potential modulators of gut health that could alleviate disease symptoms. Furthermore, the review explores how neurological diseases such as TBI, CP, and stroke disrupt the gut microbiome, promoting the overgrowth of harmful bacteria like Escherichia and Akkermansia. This disruption leads to increased gut permeability, which exacerbates systemic inflammation and worsens neuroinflammation, creating a harmful feedback loop. The paper highlights the potential of microbiome-targeted therapies–such as probiotics, fecal microbiota transplants, and dietary interventions–as promising strategies for managing and possibly preventing both neurodegenerative and neurological diseases. These findings underscore the critical role of gut-brain interactions in both disease progression and treatment.