Gastric Cytoprotective Anti-Ulcerogenic Actions of Hydroxychalcones in Rats

Abstract

The preventive effects of hydroxychalcone derivatives on ulcer formation induced by severe necrotizing agents such as 60% ethanol in 150 mM HCl (HCl-ethanol) and 0.2N NaOH in rats were examined. Among the compounds tested, 2′,4′-dihydroxychalcone gave the strongest activity in both experimental models and protected the gastric mucosa from the insult of either necrotizing agent at oral doses ranging from 1 to lOmg/kg, as evidenced by a dose-related reduction in the ulcer index. The mucosal protective activity of 2′,4′-dihydroxychalcone was not affected by pretreatment with indomethacin (5 mg/kg, s.c.). To investigate the detailed mechanism of the mucosal protective action of 2′,4′-dihydroxychalcone, its inhibitory effects on the decrease in the hexosamine content from the gastric mucus induced by HCl-ethanol were studied by using it in combination with a dye, Alcian blue. As a result, 2′,4′-dihydroxychalcone at an oral dose of 10 mg/kg inhibited the decrease in the dye-recovery from the gastric mucus induced by HCl-ethanol. PGE₂ at an oral dose of 0.1 mg/kg exhibited a similar action. These results established that 2′,4′-dihydroxychalcone is a potent cytoprotective agent similar to PGR₂ effectively preventing gastric ulcer formation induced by strong ; necrotizing agents and seems to suggest that this compound protects the stomach against its own peptic secretions by reinforcement of gastric resistances. In fact, 2′,4′-dihydroxychalcone prevented ulcer formation induced by water-immersion stress in rats and also showed a marked enhancement of the healing of acetic acid-induced gastric ulcers in rats.

Keywords

Hydroxychalcone - 2′,4′-dihydroxychalcone - Glycyrrhiza glabra - cytoprotection - necrotizing agent - anti-ulcerogenic action