研究积雪草苷(asiaticoside)对小鼠胶原诱导性关节炎(collagen-induced arthritis,CIA)的作用,并初步探讨其作用机制。建立CIA模型,检测小鼠足爪炎症的肿胀度,石蜡切片HE染色对关节组织进行病理检查,MTT法检测脾淋巴细胞增殖反应,Western blotting法检测关节软组织中环氧酶-2(cyclooxygenase-2,COX-2)蛋白的表达,EIA法测定关节软组织中前列腺素E2(prostaglandin E2,PGE2)水平,ELISA法检测血清中炎症因子TNF-α、IL-6的水平。积雪草苷(10,20及40mg·kg^-1)灌胃给药能剂量依赖性地减轻CIA小鼠的关节炎症状,抑制CIA小鼠CII胶原诱导的淋巴细胞增殖反应,减少CIA小鼠踝关节软组织中高水平的COX-2表达及PGE2含量,降低血清中炎症因子TNF-α和IL-6的水平;同时病理检查发现,可以改善局部关节炎症状,抑制CIA小鼠滑膜细胞增生,减轻炎性细胞浸润。结果表明,积雪草苷对CIA具有抑制作用,其机制可能与抑制淋巴细胞增殖、减少COX-2表达及促进炎症因子TNF-α、IL-6释放等有关。
The study is to investigate the effect of asiaticoside on collagen-induced arthritis (CIA). The model of CIA mice was prepared and the change of secondary paw swelling and the arthritis scores were observed. In vitro proliferation of spleen cells was examined using MTT assay. The cell-free protein extracts from the arthritic joints and nonarthritic joints were used for the analysis of protein expression of cyclooxygenase-2 ( COX-2). And the level of PGE2 in joints was assayed using PGE2 express EIA kit. The tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels in the serum were measured by ELISA. Histopathological examination was performed by hematoxylin-eosin (HE) stain method. Asiaticoside ( 10, 20 and 40 mg · kg^-1 · d^-1, 22 d, ig) significantly reduced paw swelling, and decreased the arthritis scores. There was a significant reduction in proliferation of spleen cells of CIA mice treated with asiaticoside as compared with that of untreated CIA mice. COX-2, PGE2, TNF-α and IL-6 production in CIA mice were inhibited by asiaticoside. Meanwhile, the pathological examination showed that articular cartilage degeneration with synovial hyperplasia and inflammatory cells infiltration in CIA mice was suppressed by asiaticoside. Its active mechanism may be related to inhibiting proliferation of lymphocyte and reduction of expression of COX-2 and inflammatory cytokines.