Berberine Reduces Rat Intestinal Tight Junction Injury Induced by Ischemia–Reperfusion Associated with the Suppression of Inducible Nitric Oxide Synthesis

Abstract

Berberine (BBR) has been shown to attenuate the deleterious effects of ischemia/reperfusion (I/R) injury in the brain. We evaluated the effects of BBR on intestinal tight junction (TJ) changes during mesenteric I/R. I/R was induced in rats by the occlusion of the superior mesenteric artery and reperfusion. The rats were randomized into four groups: control, BBR, I/R, and I/R + BBR. Intestinal permeability was determined by the lactulose/mannitol test. The ileum and colon were harvested to assess mucosal injury and inducible nitric oxide synthase activity. The TJ ultrastructure was studied by transmission electron microscopy. The expressions and locations of the TJ proteins, occludin and ZO-1, in the epithelium were investigated by immunofluorescence microscopy. We also used Western blot analysis to detect the distribution of TJ proteins in lipid raft fractions. Our results suggest that I/R-induced intestinal TJ dysfunction can be improved by BBR, thereby demonstrating the therapeutic potential of BBR for intestinal I/R.