Anti-osteoarthritis activity of urtica extracts at different concentrations / 中国组织工程研究

ABSTRACT

BACKGROUND:Urtica,as a traditional Chinese medicine,is famous for anti-inflammatory,detumescence and anti-rheumatic effects,but its effect on osteoarthritis remains unknown.OBJECTIVE:To investigate the therapeutic effect of different concentrations of urtica on osteoarthritis and the underlying mechanism.METHODS:(1) Eighteen rats were selected,and after their hair was shaved,the rats were divided into three groups (n=6 per group).The rat skin was painted with paraffin,urtica colloid and 0.8％ formaldehyde,respectively,and the skin rash and swelling were observed.(2) Thirty rats were selected,and the rat model of osteoarthritis was established by injecting papain,followed by equally allotted into 100,200,and 400 mg/kg urtica and positive control groups.The diameter of the rat left knee was measured at 1,2 and 3 weeks after administration to determine the severity of knee swelling.The rat model of acute pain was established with 0.6％ acetic acid solution,and then the model rats were subjected to different concentrations of urtica or normal saline (control group).(3) The frequency of rat tumbling and twisting was observed to determine the analgesic effect of urtica.The levels of interleukin-1β,tumor necrosis factor-α and matrix metalloproteinase 3 in the synovial fluid of the left knee joint were detected by ELISA at 1,2 and 3 weeks after administration.RESULTS AND CONCLUSION:After urtica administration,no edema or rash appeared on the rat skin surface.Compared with the control group,200 and 400 mg/kg urtica could reduce joint swelling and pain,showing no significant difference from indomethacin.Compared with the control group,200 and 400 mg/kg urtica reduced the levels of interleukin-1 β,tumor necrosis factor-α and matrix metalloproteinase 3 in the synovial fluid.These results manifest that urtica exerts the effects of anti-inflammation,analgesia,detumescence and anti-osteoarthritis.