Gamma (γ)-mangostin attenuated gastric ulcers induced by absolute alcohol in rats: Histological, immunohistochemical and biochemical investigation

Abstract Garcinia mangostana L. (Clusiaceae) principally contains gamma (γ)-mangostin, a xanthone that exhibits a wide spectrum of bioactivities. The current study was aimed to establish the gastroprotective effect of this compound in ethanol-induced gastric mucosal injuries in rats. Experimental Sprague Dawley (SD) rats (n = 30) were arbitrarily alienated into 5 groups (n = 6): negative control (10% Tween 20), ulcer control (10% Tween 20 + 5ml/kg absolute alcohol), reference control (5ml/kg absolute alcohol + 20mg/kg omeprazole), and two experimental groups (5ml/kg absolute alcohol + 10mg/kg γ-mangostin and 5ml/kg absolute alcohol + 20mg/kg γ-mangostin). After successful oral feeding, all rats were anesthetized and sacrificed. Gastro-histology highlighted severe injuries to the gastric mucosa with decrease in gastric mucosal content and gastric juice pH in ulcer control group. γ-mangostin (10 mg/kg & 20 mg/kg) showed strong gastroprotective effect by enhancing gastric mucosal content and gastric juice pH compared to the ulcer group, comparable to the omeprazole. Immuno-histochemical analysis revealed that γ-mangostin found to upregulate mucosal Hsp70 protein, and down-regulate Bax proteins. The biochemical analysis of mucosal tissue homogenate showed significant antioxidant activity with increase in SOD and CAT activities, whereas MDA was significantly decreased at p < 0.001. The histological, immuno-histochemical and biochemical analysis evidenced gastroprotective effects of γ-mangostin that are attributed to its potential to inhibit alcohol induced oxidative stress. Specifically, γ-mangostin improved histology of mucosal content and enhanced anti-oxidative enzymes (SOD & CAT) with decreasing lipid peroxidation (MDA). Furthermore dose dependent administration of γ-mangostin down-regulated expression of Bax protein and up-regulated HSP70.