Influence of the Microbiota-Gut-Brain Axis on Cognition in Alzheimer's Disease Author: Yael-Natalie H Escobar1,2, Devin O&#39;Piela1,2, Loren E Wold1,2,3, Amy R Mackos1,2 Affiliation: <sup>1</sup> Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH, USA. <sup>2</sup> College of Nursing, The Ohio State University, Columbus, OH, USA. <sup>3</sup> Department of Physiology and Cell Biology, The Ohio State University College of Medicine and Wexner Medical Center, Columbus, OH, USA. Conference/Journal: J Alzheimers Dis Date published: 2022 Mar 2 Other: Special Notes: doi: 10.3233/JAD-215290. , Word Count: 201 The gut microbiota is made up of trillions of microbial cells including bacteria, viruses, fungi, and other microbial bodies and is greatly involved in the maintenance of proper health of the host body. In particular, the gut microbiota has been shown to not only be involved in brain development but also in the modulation of behavior, neuropsychiatric disorders, and neurodegenerative diseases including Alzheimer's disease. The precise mechanism by which the gut microbiota can affect the development of Alzheimer's disease is unknown, but the gut microbiota is thought to communicate with the brain directly via the vagus nerve or indirectly through signaling molecules such as cytokines, neuroendocrine hormones, bacterial components, neuroactive molecules, or microbial metabolites such as short-chain fatty acids. In particular, interventions such as probiotic supplementation, fecal microbiota transfer, and supplementation with microbial metabolites have been used not only to study the effects that the gut microbiota has on behavior and cognitive function, but also as potential therapeutics for Alzheimer's disease. A few of these interventions, such as probiotics, are promising candidates for the improvement of cognition in Alzheimer 's disease and are the focus of this review. Keywords: Alzheimer’s disease; cognition; microbiota-gut-brain axis; mild cognitive impairment. PMID: 35253750 DOI: 10.3233/JAD-215290