Analgesic and Anti-Inflammatory Activities of the Methanol Extract ofKalanchoe gracilis(L.) DC Stem in Mice
In this study, we evaluated the analgesic effect of the methanol extract of Kalanchoe gracilis (MKGS) stem in animal models by inducing writhing response with acetic acid and conducting formalin test. The anti-inflammatory effect of MKGS was also estimated on mice with λ-carrageenan induced paw edema model. In order to investigate the anti-inflammatory mechanism of MKGS, we analyzed the activities of glutathione peroxidase (GPx) and glutathione reductase (GRx) in the liver, and the levels of interleukin-1β (IL-1β), tumor necrosis factor (TNF-α), malondialdehyde (MDA) and nitric oxide (NO) in the edema paw tissue. In the analgesic tests, MKGS (0.5 and 1.0 g/kg) decreased both the acetic acid-induced writhing response and the licking time in the late phase of the formalin test. In the anti-inflammatory test, MKGS (0.1, 0.5 and 1.0 g/kg) decreased paw edema at the third, fourth, fifth and sixth hours after λ-carrageenan had been administrated. Furthermore, MKGS increased the activities of SOD and GRx in liver tissues and decreased MDA level in the edema paws three hours after λ-carrageenan was injected. MKGS also affected the levels of IL-1β, TNF-α and NO induced by λ-carrageenan. All these results suggested that MKGS possessed analgesic and anti-inflammatory effects. The anti-inflammatory mechanism of MKGS might be related to the lowering of MDA level in the edema paw via increasing the activities of superoxide dismutase (SOD) and GRx in the liver, as well as the decreases in the levels of TNF-α and NO, and the production of IL-1β in inflamed tissues.