Influence of low and high doses of capsicum extract on indomethacin induced gastric ulcer in rats

Background: Capsicum (Caps) has always been used as food spice. Recently, it has shown benefits in peptic ulcer but effective dose range and mechanisms mediating its effect are not known. This work is aimedto evaluate the gastroprotective effect of a wide dose range of Caps, compared with ranitidine (Ran), against indomethacin (Indo)-induced ulcer. Methods: 42 female adult Wistar albino rats were allocated into seven groups: 1) control (Cnt), 2) Indo (25 mg/kg p.o.), groups 3-6 were given Caps at 200, 400, 800 and 1600 mg/kg, p.o. prophylactically for 6 days. The last group was given 100 mg/kg, p.o. Ran for 6 days. Blood samples were withdrawn for analysis of MDA, GSH, NO, and SOD and stomachs were dissected for histopathological examinations and measurement of TNF-α and IL-8. Results: Caps replenished GSH and SOD and reduced TNF-α, IL-8, MDA and NO. It also reduced mucosal focal ulceration, neutrophil infiltration, ulcer index in a dose dependent manner. Importantly, Caps ulcer-protective effects were equivalent to those of 100 mg/kg Ran at 800 and 1600 mg/kg with an ED50% of 350 mg/kg. Conclusion: Caps extract possesses a dose-dependent ulcer-protective effect that is equivalent to that of Ran at relatively high doses.