Expression of TJs proteins in colonic biopsies from patients with Parkinson’s disease (PD) and control subjects (CTRL). Biopsies lysates (20 μg of protein per sample) were subjected to immunoblot analysis using antibodies against occludin and ZO-1 (A). Beta-actin was used as a loading control. The optical densities of occludin (B) and ZO-1 (C) immunoreactive bands were measured, normalized to the optical densities of beta-actin immunoreactive bands in the same samples and expressed as percentages of controls. Data correspond to mean ± SEM of 11 samples for control subjects (CTRL) and 31 samples for Parkinson’s disease (PD) patients. Patients versus control, *: p < 0.05.