Role of the gut microbiome in Alzheimer's disease.

Alzheimer's disease (AD) is the most common form of dementia, affecting millions of individuals each year and this number is expected to significantly increase. The complicated microorganisms residing in human gut are closely associated with our health. Emerging evidence has suggested possible involvement of human gut microbiome in AD. Symbiotic gut microbiomes are known to maintain brain health by modulating host's barriers integrity, metabolic system, immune system, nervous system and endocrine system. However, in the event of gut dysbiosis and barriers disruption, gut pathobionts disrupt homeostasis of the metabolic system, immune system, nervous system, and endocrine system, resulting in deterioration of neurological functions and subsequently promoting development of AD. Multiple therapeutic approaches, such as fecal microbiome transplant, antibiotics, prebiotics, probiotics, symbiotic, and diet are discussed as potential treatment options for AD by manipulating the gut microbiome to reverse pathological alteration in the systems above.