The interplay of gut microbiota in neurodegenerative disorders

Globally, populations are burdened with significant medical and public health costs due to degenerative illnesses of the neurological system. A couple among the most common neurodegenerative conditions include Parkinson's disease (PD) and Alzheimer's disease (AD). Since these illnesses are more common and more severe as people age, more instances are anticipated soon as life expectancy continues to climb in many nations. Numerous studies throughout the years have revealed the genetic and metabolic processes that contribute to neurodegenerative disorders (NDDs). The microbial community in the human gut is diverse and dynamic, and it is crucial to numerous physiological processes. It has been demonstrated that the gut microbiota (GM) is a part of the gut-brain axis (GBA) in a number of regulatory mechanisms and associated pathways, as well as in unique bacterial behaviors. Besides, it has been established that GM pose a danger for neurological problems that impact the neurological system, especially CNS, or central nervous system, controlling the course of the disease and being responsive to treatment. The GBA promotes communication in both directions between the GM and the brain, indicating that it is essential for neurocrine, endocrine, and immune signaling pathways. This review clarifies the complex interaction between gut bacteria and human health, with a focus on how it affects neurodegenerative diseases. Moreover, we have discussed the crucial role of the GM in the GBA from the brain to the gut and the gut to the brain, as well as the neurological pathways that interact with the GM.