Protective Effects of Miswak (Salvadora persica) against Experimentally Induced Gastric Ulcers in Rats.

Gastric ulcers are among the most broadly perceived illnesses affecting individuals. Alcohol consumption is the main cause of gastric ulceration. This study assessed the protective effects of Salvadora persica (SP) extract against ethanol-induced gastric ulcer and elucidated the conceivable underlying mechanisms involved. For this purpose, 40 rats were allotted into 4 equal groups (control, ethanol- (EtOH-) treated, and SP-treated "SP200 and SP400" groups). The control and EtOH-treated groups were given phosphate buffer saline (PBS), and both the SP200 and SP400 groups were given SP extract dissolved in PBS at doses of 200 and 400 mg/kg b.w., respectively. All treatments were given orally for 7 constitutive days. On the 8th day, all rats were fasted for 24 h followed by oral gavage of PBS in the control group and chilled absolute ethanol solution (5 ml/kg b.w.) in the EtOH- and SP-treated groups to induce gastric lesions. One hour later, the rats were sacrificed and the stomachs were harvested. Gross and microscopic examinations of the EtOH-treated group showed severe gastric hemorrhagic necrosis, submucosal edema, destruction of epithelial cells, and reduced glycoprotein content at the mucus surface. These pathological lesions were defeated by SP extract treatment. Administration of SP extract modulated the oxidative stress and augmented the antioxidant defenses. The elevated ethanol-expressed tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) genes, as well as bcl-2-like protein 4 (Bax) and inducible nitric oxide synthase (iNOS), were diminished in the SP-treated group. Curiously, SP extract upregulated endothelial nitric oxide synthase (eNOS) and transforming growth factor-β1 (TGF-β1) gene expression comparable to that of the EtOH-treated rats. Aggregately, SP exerted antiulcer activities in ethanol-induced gastric ulcer rat models via modulation of oxidant/antioxidant status, mitigation of proinflammatory cytokines, and apoptosis, as well as remodeling of both NOS isoforms.