Role of Microbial Toxins in Neurodegenerative Diseases: Insights and Future Perspectives

Neurodegenerative disorders, including Parkinson’s, Alzheimer’s, and multiple sclerosis, are significant global health issues characterized by escalating neuronal dysfunction and cognitive decline. Studies suggest that microbial toxins originating from fungi and bacteria may contribute to neurodegenerative processes by altering neuronal homeostasis in several ways. Toxins formerly associated with infectious diseases have now been associated with neuroinflammation, oxidative stress, and protein misfolding, all of which are common in neurodegenerative diseases. According to recent studies, microbial toxins generated by the gut microbiota may cross the blood–brain barrier and possibly contribute to neuroinflammatory cascades linked to the development of neurodegenerative diseases. The complex interplay of microbial metabolites, microbial responses, and mitochondrial dysfunction demonstrates the diverse character of neurodegenerative processes. This review delves into the current understanding of microbial toxins, which are produced by diverse bacteria and can have a direct or indirect impact on neuronal health via multiple signaling pathways. Understanding the signaling mechanisms of microbial and toxin-mediated neurodegenerative diseases could result in the development of effective alternative therapeutics for neurological disorders.