Treatment with 3 mg/kg SAC showed better inhibitory effects than rebamipide (30 mg/kg), which is a well-known mucosal-protective antiulcer drug, on mucosal damages induced by indomethacin. The mean pathology index of gastric damage was all significantly decreased in mice pretreated with low dosage of SAC (3–10 mg/kg), whereas 20 mg/kg SAC did not provide preventive effect, suggesting that less than 10 mg/kg SAC treatment afforded significantly preventive effect against indomethacin-induced

gastric ulcerogenesis. COX-2 is a representative pro-inflammatory mediator in GI damages, by which selleck chemical several drugs or strategy had been tried to prevent various GI ulcers. To determine whether the preventive effect of SAC on indomethacin-induced gastric damage is caused by inhibiting the expression of COX-2, we performed Western blot analysis (Fig. 2a). Treatment with indomethacin resulted in a marked induction

of the expression of COX-2 protein, indicating its involvement in indomethacin-induced gastric damage. SAC showed significant inhibitory effects more than rebamipide on the expression of COX-2 (Fig. 2a). However, as far as COX-2 inhibition, 10–30 mg/kg SAC was better than 3 mg/kg SAC. To also confirm the activity of COX-2, we measured the production of PGE2, the major metabolite of COX-2 through enzyme immunoassay. PGE2 levels were significantly increased in indomethacin-treated group compared with the vehicle-treated group, but pretreatment find protocol of 10–30 mg/kg SAC reversed the overproduced PGE2 to the basal level (Fig. 2b). This result is consistent with COX-2 expression (Fig. 2a). Next, we employed 上海皓元医药股份有限公司 ELISA assay using serum samples to identify

whether preventive effects of SAC against NSAID-induced gastric damages are related with the suppression of cytokines and chemokines, known to participate in NSAID-induced gastric ulcerogenesis. As shown in Figure 2c–e, serum levels of IL-1β (Fig. 2c), TNF-α (Fig. 2d), and IL-6 (Fig. 2e) were all significantly increased after indomethacin administration (P < 0.05), but SAC significantly attenuated the upregulated levels of IL-11β, TNF-α, and IL-6 more than rebamipide (P < 0.05). To investigate the contribution of preserved mucus against indomethacin-induced gastric damage, we performed periodic acid Schiff (PAS) staining. As seen in Figure 3, PAS staining of normal gastric tissues showed abundant presence of mucus within the goblet cell thecae, but loss of PAS-positive mucus cells after indomethacin treatment. However, SAC treatment preserved PAS-positive gastric glands in spite of indomethacin treatment, while rebamipide did not afford these privileges of mucus preservation. To assess the apoptotic cell death in the stomach, we stained formalin-fixed, paraffin-embedded stomach sections by using a TUNEL assay (Fig. 3b). The numbers of TUNEL-positive epithelial cells were counted in each of 10 sections and expressed as a percentage of the total epithelial cells.