The prevalence of neurological diseases such as Alzheimer’s disease (AD),
Parkinson’s disease (PD), and Multiple sclerosis (MS) are growing in the world, but
their pathogenesis is unclear and effective treatment does not exist. Neuroinflammation
is associated with many neurodegenerative mechanisms involved in neurodegenerative
diseases. The human gut microbiota is an aggregate of microorganisms that live in the
gastrointestinal tract (GIT) that plays a crucial role in maintaining human health and
the pathogenesis disease condition. The microbiota can affect neuronal function
through neurotransmitters, vitamins, and neuroactive microbial metabolites like shortchain fatty acids. The change in gut microbiota architecture causes increased
permeability of the intestine and immune system activation, contributing to systemic
inflammation, neurological injury, and eventually neurodegeneration. Available data
suggest that the microbiota send signals to the central nervous system (CNS) by
activating afferent neurons of the vagus nerve via neuroendocrine and neuroimmune
pathways. The molecular interaction between the gut/microbiome and CNS is complex
and bidirectional, ensuring gut homeostasis and proper digestion. Evidence suggests
that dysfunction of the gut-brain axis could be a significant factor leading to many
disorders of CNS. In this chapter, we explore how the gut microbiome may affect brain
function and the development of neurological disorders. In addition, we are also trying
to highlight the recent advances in improving neurological disease by supplemental
probiotics and faecal microbiota transplantation via the concept of the gut-brain axis to
combat brain-related dysfunction.
Keywords: Alzheimer’s disease, Central nervous system, Parkinson’s disease, Gastrointestinal tract, Microbiota, Multiple sclerosis, Neuroinflammation.
