Human gut microbiota and Parkinson Disease

Abstract

Human gut microbiota (GM) has now been accepted as a potential modulator ofhuman biology. Although new to the world of science, GM's impaction brain and behavior has drawn great attention around the globe. Studies have now proven that GM can directly or indirectly modify brain neurochemistry via various mechanisms like neural, immune and endocrine. The intestinal microbiota influence neurodevelopment, modulate behavior, and contribute to neurological disorders. This presentation is an overview of recent findings regarding the GM -brain axis in PD (Braniste et al. 2014; Sampson et al. 2016) Parkinson disease (PD) is the second-most common neurodegenerative disorder. PD patients show alpha-synuclein deposits and neurodegeneration in the enteric nervous system as well as breakdown of the mucosal barrier, bacterial invasion, and mucosal inflammation in the colon. Alterations in GM and increased gut permeability may influence PD pathophysiology via epigenetic processes that alter αSyn regulation (Matsumoto et al. 2010). Sampson et al. (2016) suggest that GM are required for the hallmark motor and GI dysfunction in a mouse model of PD, via postnatal gut-brain signaling by microbial molecules that impact neuroinflammation and αSyn aggregation. They propose that GM regulate movement disorders and suggest that alterations in thehuman microbiome represent a risk factor for PD. GM do not only affect gut physiology, but there is also an intense bidirectional interaction with the brain influencing neuronal activity, behavior, as well as levels of neurotransmitter receptors, neurotrophic factors, and inflammation. Recently, gut microbiome alterations in PD subjects and a connection between GM and motoras well as non-motor symptoms have been described (Sampson et al. 2016; Parashar and Udayabanu 2017)