Study of the gastroprotective action and healing effects of Kalanchoe pinnata (Lam.) against acidified ethanol- and acetic acid-induced gastric ulcers in rats / Estudo da acção gastroprotectora e dos efeitos curativos de Kalanchoe pinnata (Lam.) contra úlceras gástricas induzidas por etanol acidificado e ácido acético em ratos

Abstract

Kalanchoe pinnata (Lam.) Pers. (Crassulaceae) is a commonly used species in traditional medicine in Brazil for the treatment of various diseases, including gastric ulcers. This research aims to evaluate the antiulcer aspects of Kalanchoe pinnata leaves. The LD50 value of the hydroethanolic extract (HE) of K. pinnata was 1341.46 mg/kg, after the in vitro cytotoxicity assay. In the phytochemical analysis, several flavonoids were identified in the HE and ethyl acetate fraction (EAF) of K. pinnata. It was verified that the gastroprotective activity of the HE of K. pinnata involved prostaglandins and sulfhydryl compounds. However, the mechanism of gastroprotection of the EAF of K. pinnata is dependent on prostaglandins and nitric oxide. The ulcer healing activity of the HE of K. pinnata was also evaluated. According to the macroscopic results, doses of 200 mg/kg and 400 mg/kg reduced the injury area, with rates of 33% and 39%, respectively, after 7 days of treatment (p <0.05). Histological analysis showed regeneration of the gastric mucosa and re-establishment of the glandular architecture in groups treated with the HE (200 and 400 mg/kg). Antioxidant enzymes (CAT, SOD and GPx) were evaluated in the mechanism of gastric ulcer healing. The results showed that the antiulcerogenic activity was mediated by SOD. The anti-Helicobacter pylori activity was also evaluated; however, the HE did not show anti-H. pylori activity. Analysis of the results suggests that K. pinnata has therapeutic potential against gastric ulcers and that the flavonoids may be linked to the biological effects.