Gastroprotective effects of Tunisian green clay on ethanol-induced gastric mucosal lesion in rats

Abstract Natural green clay is mostly used in pharmaceutical and cosmetic products. The effect of this raw material from different outcrops around the world demonstrates its beneficial role on human health. The green clay from southern Tunisia is widely used in local traditional medicine and cosmetic preparations but its biological activity in vivo has not been studied yet. For this reason, this work was interested in deciphering the properties of the Tunisian green clay such as mineralogy composition and biological effect. In fact, the mineralogical study of this green clay shows two types of clay minerals such as illite and kaolinite with proportion of 75% and 25%, respectively. In order to study the biological effect, green clay was administered orally to rats for 1 h at 50, 75, 100 and 125 mg/kg doses. After that, ethanol 95% was given to these rats to induce a gastric ulcer. Then, several parameters (e.g. Ulcer index, protective rate, mucus production gastric and mucosa histology) were measured to evaluate the gastroprotective activity. The histology study shows normal gastric mucosa in rats pretreated at 75, 100 and 125 mg/kg doses and the decrease of Ulcer Index (%I = 97%) and lesions areas. The oral administing mixture of Tunisian green clay with ethanol in rats induces severe mucosal lesion and hemorrhagic bands. This clay colored by methylene blue shows that clay was linked to the mucus excreted by the stomach surface. The green clay didn't neutralize ethanol gastro toxicity and formed a layer on the gastric mucosa to protect it by a mechanical action. When investigated on rats at an effective dose treatment (75 mg/kg) for 30 days, the subchronic toxicity test of green clay did not reveal any signs of mortality and toxicity, and it demonstrated the normal hematological and biochemical parameters of rats. Thus, the Tunisian green clay can be considered as a safe natural product since it has a potential gastroprotective activity on ethanol induced gastric mucosal lesions in rats.