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 0.2 N 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 10 mg/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 PGE2 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.

Anti-ulcerogenic properties of the aqueous and methanol extracts from the leaves of Solanum torvum Swartz (Solanaceae) in rats

“…It is also well known that prostaglandins synthetized in large quantities by the gastrointestinal mucosa can prevent experimentally induced ulcers by ulcerogens. Thus, when the ulcers lesions are induced by indomethacin, the cytoprotective effect of the anti-ulcer agent can be mediated through endogeneous prostaglandins (Yamamoto et al, 1998). The results obtained show that the ulcer surface area and the mean ulcer index were significantly reduced, while the mucus weight increased in the aqueous and methanol extracts treated groups, compared to their respective controls.…”

Short Communication: The antiulcer effects of the methanol extract of the leaves of <i>Aspilia africana</i> (Asteraceae) in rats

“…It can be thought that the cytoprotective effect of the extract results from the enhancement of the mucosal barrier through the increase production of prostanglandin. Yamamoto et al (1992) and Tan et al (2000) have shown the prostaglandin-like cytoprotective action of some hydroxychalcone and methylene chloride extract of Bidens pilosa respectively and the methanol leaf extract of A. africana might be producing its antiulcer effects through the same mechanism. The anti-ulcer effects of the methanol extract of the leaves of Aspilia africana may be due to the presence of triterpenes in the extract.…”

Gastroprotective activity of Trichosanthes cucumerina in rats

“…It is also well known that prostaglandins synthesized in large quantities by the gastrointestinal mucosa can prevent experimentally induced ulcers by ulcerogens. Thus, when the ulcer lesions are induced by absolute ethanol or indomethacin, the cytoprotective effect of the antiulcer agent can mediated through endogeneous prostaglandins (Yamamoto et al, 1992). Therefore, it can be thought that HWE may stimulate the secretion of prostaglandin or possess prostaglandin like substances.…”