Effectiveness of the polyphenols-rich Sedum dendroideum infusion on gastric ulcer healing in rats: Roles of protective endogenous factors and antioxidant and anti-inflammatory mechanisms

Ethnopharmacological relevance: Peptic ulcer is an inflammatory disease that therapeutic options are mainly focused in antisecretory drugs. Sedum dendroideum Moc & Sesse acute accent ex DC (Crassulaceae) is employed in folk medicine for the treatment of gastric ulcers. Recently, our group demonstrated that Sedum dendroideum infusion (SDI) is rich in polyphenols (flavonol glycosides, myricetin, quercetin and kaempferol) and promoted gastroprotection against acute ulcer models, without changes gastric acid secretion. Aim of the study: Here, we follow the investigation of the healing effects of SDI (ED50 = 191 mg/kg) in the chronic gastric ulcer model induced by 80% acetic acid in rats, elucidating underlying mechanisms. Material and methods: Rats were orally treated with vehicle (water, 1 mL/kg), SDI (191 mg/kg), omeprazole (40 mg/kg) or sucralfate (100 mg/kg) twice daily for 5 days after ulcer induction. Following treatments, toxicological effects, macroscopic ulcer appearance, microscopic histological (HE, mucin PAS-staining) and immunohistochemical (PCNA and HSP70) analysis, inflammatory (MPO and NAG activity, cytokine levels measurements) and antioxidant (SOD and CAT) parameters were investigated in gastric ulcer tissues. Results: Oral treatment with SDI accelerated gastric ulcer healing, maintained mucin content and promoted epithelial cell proliferation. SDI also reduced neutrophil and mononuclear leukocyte infiltration, TNF-alpha and IL-1 beta levels and the oxidative stress, restoring SOD and CAT activities in the ulcer tissue. Conclusions: The gastric healing effect of SDI was mediated through endogenous protective events as well as due to the anti-inflammatory and antioxidant actions. Our observations support and reinforce the traditional utilize of Sedum dendroideum as a natural nontoxic therapeutic alternative for the treatment of gastric ulcers.