title: Serotonergic mediated body mass index changes in Parkinson's disease.
abstract: More than 50% of patients with Parkinson's disease (PD) are expected to show abnormalities with their weight in a process that starts several years before the diagnosis. The serotonergic (5-HT) system has been proposed to regulate appetite and the 5-HT transporter (SERT) is a key modulator of 5-HT metabolism. Here, we hypothesized that a dysfunctional 5-HT system could be responsible for alterations of weight in PD and we sought to investigate this in vivo. Thirty four PD patients had Body Mass Index (BMI) changes monitored over a 12-month period and one positron emission tomography (PET) brain scan with (11)C-DASB, a selective marker of SERT availability, during their second clinical assessment. Results were compared with those of a group of 10 normal controls. Half (17) of the PD patients showed abnormal BMI changes over the 12-month period; 12 lost while 5 gained weight. PD patients with abnormal BMI changes showed significantly raised (11)C-DASB binding in rostral raphe nuclei, hypothalamus, caudate nucleus and ventral striatum compared to cases with no significant BMI changes. (11)C-DASB binding in other regions was similarly decreased in the PD BMI subgroups compared to normal controls. BMI gainers showed significantly raised (11)C-DASB binding in anterior cingulate cortex (ACC) compared to BMI losers. Our findings suggest that abnormal BMI changes over a 12-month period are linked with relatively raised SERT availability in PD on an overall background of decreased 5-HT function. The regions implicated are the rostral raphe nuclei and its connections to limbic and cognitive areas. It is conceivable that 5-HT agents could help alleviate abnormal changes in BMI in PD.
authors.affiliation: Centre for Neuroscience, Division of Experimental Medicine, Hammersmith Hospital, Imperial College London, London, UK. marios.politis@imperial.ac.uk
authors.forename: Marios
authors.initials: M
authors.lastname: Politis
authors.forename: Clare
authors.initials: C
authors.lastname: Loane
authors.forename: Kit
authors.initials: K
authors.lastname: Wu
authors.forename: David J
authors.initials: DJ
authors.lastname: Brooks
authors.forename: Paola
authors.initials: P
authors.lastname: Piccini
mesh_terms: D000368:Aged; D001066:Appetite / Q000502:physiology; D001596:Benzylamines; D015992:Body Mass Index; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism; D002250:Carbon Radioisotopes; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000378:metabolism*; D049268:Positron-Emission Tomography / Q000379:methods; D012701:Serotonin / Q000378:metabolism / Q000502:physiology*; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism
chemical_list: D001596:Benzylamines; D002250:Carbon Radioisotopes; C420885:N,N-dimethyl-2-(2-amino-4-cyanophenylthio)benzylamine; D050486:Serotonin Plasma Membrane Transport Proteins; D012701:Serotonin