Background: Green tea possesses gastroprotective effects via different mechanisms including lipoxygenase inhibition. We compared its protective effects with licofelone (as a potent lipoxygenase inhibitor) on reducing the incidence of gastric ulcer caused by indomethacin.
Methods: 48 rats received aqueous extract of green tea (GTAE; 50, 100 and 200 mg/kg), licofelone (30 mg/kg), zileuton (100 mg/kg), or 0.18% Tween 80 in presence of indomethacin (100 mg/kg). Two groups received only GTAE (200 mg/kg) or indomethacin (100 mg/kg). The gastric ulcer index and Malondialdehyde (MDA) in gastric tissues was evaluated. To investigate analgesic effect in acute and chronic phase, 24 rats received GTAE (200 mg/kg), licofelone (30 mg/kg), indomethacin (30 mg/kg), or 0.18% Tween 80 in presence of formalin (2.5%). Then behavior of rats was monitored for 30 minutes (minutes 0 to 5 and 25 to 30) for licking and biting feet and tail.
Results: Indomethacin (100 mg/kg) produced clear macroscopic lesions compared to the control group. GTAE (100 and 200 mg/kg), licofelone, and Zileuton showed a significant decrease in wound score compared to indomethacin. GTAE (100 mg/kg and 200), licofelone, and zileuton, displayed a significant decrease in MDA content of gastric tissue compared to the indomethacin group. Notably, GTAE exerted greater benefits than licofelone. Besides, GTAE (200 mg/kg) showed a significant decrease observed in both acute and chronic stages of pain compared to licofelone (30 mg/kg).
Conclusion: GTAE (200 mg/kg) possesses anti-ulcer and analgesic effects similar to licofelone. The exact mechanism is probably via inhibition of lipoxygenase (LOX) and antioxidant effects.