Apple polyphenol extracts prevent aspirin-induced damage to the rat gastric mucosa.

Aspirin causes gastroduodenal ulcers and complications. Food bioactive compounds could exert beneficial effects in the gastrointestinal tract. We evaluated whether apple polyphenol extract (APE) reduced aspirin-induced injury to the rat gastric mucosa. Rats were treated with APE (10(-4) m catechin equivalent) before oral aspirin (200 mg/kg). Cyclo-oxygenase-2 (COX-2), transforming growth factor-alpha (TGF alpha) and heparin-binding epidermal-growth-factor-like growth factor (HB-EGF) mRNA and protein expression were assessed by RT-PCR and Western blot analysis, respectively; malondialdehyde (MDA) was determined by HPLC; gastric secretion was evaluated in pylorus-ligated rats. APE decreased acute and chronic aspirin injury both macroscopically and microscopically (approximately 50 % decrease in lesion score; P < 0.05). Aspirin up-regulated mRNA and protein expression of COX-2 and HB-EGF, but not of TGF alpha; APE reduced aspirin-induced mRNA and protein over-expression of COX-2 and HB-EGF; aspirin significantly increased gastric MDA and this effect was counteracted by APE pre-treatment. APE did not significantly affect gastric acid secretion. In conclusion, APE reduces aspirin-induced gastric injury independently of acid inhibition. We speculate that APE might be of therapeutic use in the prophylaxis of aspirin-related gastropathy.