Anti-inflammatory and Analgesic Effects of Extract from Roots and Leaves of Citrullus lanatus

Objective To study anti-inflammatory and analgesic effects of extract from the roots and leaves of Citrullus lanatus and assess their acute toxicity in animals. Methods The mouse model with ear edema induced by xylene and the rat model with paw edema or granuloma by carrageenin or cotton pellet were used for anti-inflammatory effects of the extract. Effects of the extract on analgesia was tested respectively by measuring the latency of mice licking hind foot from hot plates and by counting the times of body twisting in response to acetic acid. The acute toxicity of the extract was determined with the method of Bliss. Results The extract significantly inhibited the ear edema, granuloma hyperplasia, and paw edema. It significantly lifted the pain threshold on mouse hot-plate responses and reduced their writhing times. During the 7 d observation period in its acute toxicity assay, no apparent toxic reaction was shown and all mice survived at a dose of 87 g extract per kg body weight. Conclusion The extract could protecte mice/rates from inflammation and analgesia, and may be safe as an orally administered natural product for humans.