title: Gut dysfunction in Parkinson's disease.
abstract: Early involvement of gut is observed in Parkinson's disease (PD) and symptoms such as constipation may precede motor symptoms. α-Synuclein pathology is extensively evident in the gut and appears to follow a rostrocaudal gradient. The gut may act as the starting point of PD pathology with spread toward the central nervous system. This spread of the synuclein pathology raises the possibility of prion-like propagation in PD pathogenesis. Recently, the role of gut microbiota in PD pathogenesis has received attention and some phenotypic correlation has also been shown. The extensive involvement of the gut in PD even in its early stages has led to the evaluation of enteric α-synuclein as a possible biomarker of early PD. The clinical manifestations of gastrointestinal dysfunction in PD include malnutrition, oral and dental disorders, sialorrhea, dysphagia, gastroparesis, constipation, and defecatory dysfunction. These conditions are quite distressing for the patients and require relevant investigations and adequate management. Treatment usually involves both pharmacological and non-pharmacological measures. One important aspect of gut dysfunction is its contribution to the clinical fluctuations in PD. Dysphagia and gastroparesis lead to inadequate absorption of oral anti-PD medications. These lead to response fluctuations, particularly delayed-on and no-on, and there is significant relationship between levodopa pharmacokinetics and gastric emptying in patients with PD. Therefore, in such cases, alternative routes of administration or drug delivery systems may be required.
authors.affiliation: Adreesh Mukherjee, Atanu Biswas, Shyamal Kumar Das, Department of Neurology, Bangur Institute of Neurosciences and Institute of Post Graduate Medical Education and Research, Kolkata, West Bengal 700025, India.
authors.forename: Adreesh
authors.initials: A
authors.lastname: Mukherjee
authors.affiliation: Adreesh Mukherjee, Atanu Biswas, Shyamal Kumar Das, Department of Neurology, Bangur Institute of Neurosciences and Institute of Post Graduate Medical Education and Research, Kolkata, West Bengal 700025, India.
authors.forename: Atanu
authors.initials: A
authors.lastname: Biswas
authors.affiliation: Adreesh Mukherjee, Atanu Biswas, Shyamal Kumar Das, Department of Neurology, Bangur Institute of Neurosciences and Institute of Post Graduate Medical Education and Research, Kolkata, West Bengal 700025, India.
authors.forename: Shyamal Kumar
authors.initials: SK
authors.lastname: Das
mesh_terms: D000978:Antiparkinson Agents / Q000378:metabolism; D003248:Constipation / Q000209:etiology* / Q000503:physiopathology; D003680:Deglutition Disorders / Q000209:etiology* / Q000503:physiopathology; D017615:Enteric Nervous System / Q000503:physiopathology; D065569:Gastrointestinal Absorption; D000069196:Gastrointestinal Microbiome; D041981:Gastrointestinal Tract / Q000378:metabolism; D018589:Gastroparesis / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D044342:Malnutrition / Q000209:etiology* / Q000503:physiopathology; D010300:Parkinson Disease / Q000150:complications* / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology; D012798:Sialorrhea / Q000209:etiology* / Q000503:physiopathology; D051844:alpha-Synuclein / Q000378:metabolism
chemical_list: D000978:Antiparkinson Agents; D051844:alpha-Synuclein
keywords: Constipation; Dysphagia; Gastroparesis; Gut dysfunction; Gut microbiota; Parkinson’s disease; Sialorrhea