The Total Flavonoid Extract from Glycyrrhiza inflat Bat. Suppresses Atrophic Gastritis in Rats through the Akt/MAPK Pathway

Abstract

Ethnopharmacological Relevance. Glycyrrhiza inflat Bat. is widely used to treat gastric ulcer and gastritis in clinic in China. Aim of the Study. To investigate the protective effects and possible mechanisms of the total flavonoid extract (TFE) from G. inflat Bat. on atrophic gastritis (AG) rats. Materials and Methods. The rat AG model was established by providing sodium deoxycholate and alcohol, and then, AG rats were treated with TFE for 30 days. Pathologic changes in gastric specimens were observed using hematoxylin and eosin staining, and the capability of gastric mucosa to secrete mucus was examined by alcian blue-periodic acid Schiff staining. Apoptosis induction in gastric tissues was measured by the TUNEL assay. The expressions of Bcl-2, Bax, and proteins in the Akt/MAPK pathway in gastric tissues were examined by immunohistochemistry and/or Western blotting. Results. Compared with the AG group, TFE attenuated the damage of gastric mucosa as reflected by the thickening of the lamina propria and the thinning of the muscularis mucosae. Moreover, TFE induced apoptosis in gastric mucosa with increasing Bax/Bcl-2 expression ratio. Concomitantly, the degrees of p-ErkThr202/Tyr204 and p-AktThr308 were decreased, whereas those of p-p38Thr180/Tyr182 and p-JNKThr183/Tyr185 were increased. Conclusion. We demonstrated the anti-AG effect of G. inflat Bat. in vivo and elucidated the underlying mechanisms that involve gastric mucosa protection through the Akt/MAPK pathway. The study provides a rationale for the application of G. inflat Bat. in the treatment of AG.