Cyclooxygenase inhibitors counteract pro-fibrotic signalling in experimental colitis through modulation of TGF-beta/SMAD network

Aims. Cyclooxygenase isoforms (COX-1, COX-2) have been implicated in the development of fibrosis at gastrointestinal sites. Under bowel inflammation, transforming growth factor beta (TGF-beta) has been identified as the main regulator of fibrotic remodelling. The present study investigated the effects of cyclooxygenase inhibitors on pro-fibrotic signalling mediated by the TGF-beta/SMAD pathway in experimental colitis. Methods. Colitis was induced in rats by intrarectal 2,4-dinitrobenzenesulfonic acid (DNBS, 30 mg/rat in 0.25 ml ethanol 50%). After 6 days, systemic [body and spleen weight] and tissue inflammatory parameters [macroscopic and microscopic damage] were assessed. Three days befor…

Control of enteric neuromuscular functions by purinergic P2X7 receptors in normal rat distal colon and experimental bowel inflammation

Introduction: Purinergic signalling plays a pivotal role in the physiological regulation of several enteric functions, as well as in the modulation of immune/inflammatory cell activity. Recent evidence has shown an active involvement of the purinergic P2X7 receptor (P2X7R) in the fine tuning of immune functions, as well as its critical role in driving enteric neuron apoptosis under intestinal inflammation. However, the participation of this receptor pathway in the regulation of enteric neuromuscular functions remains undetermined. Aims: This study investigated the role of P2X7Rs in the control of colonic motility, both under normal conditions and in the presence of experimental colitis. Met…

In rat fibrotic colon TGF-beta/SMAD signalling is modulated by cyclooxygenases inihibitors