Lin N, Sato T, Ito A
Institute of Chinese Materia Medica, China Academy of Traditional Chinese Medicine, Beijing.
Arthritis Rheum. 2001 Sep;44(9):2193-200. doi: 10.1002/1529-0131(200109)44:9<2193::aid-art373>3.0.co;2-5.
Various extracts of the Chinese herbal remedy Tripterygium wilfordii Hook. f. (TWHF) have been reported to be therapeutically efficacious in rheumatoid arthritis (RA) in China, but their mechanism of action remains unclear. We investigated the effect of triptolide, a diterpenoid triepoxide from TWHF, on the production of pro-matrix metalloproteinase 1 (proMMP-1; or procollagenase 1 or pro-interstitial collagenase 1), proMMP-3 (or prostromelysin 1), tissue inhibitors of metalloproteinases (TIMPs), and proinflammatory cytokines in human synovial fibroblasts and J774A.1 mouse macrophages.
Human synovial fibroblasts and mouse macrophages were cultured with interleukin-1alpha (IL-1alpha) or lipopolysaccharide (LPS) in the presence or absence of triptolide. The production of proMMPs 1 and 3, TIMPs 1 and 2, cyclooxygenase 1 (COX-1) and COX-2, prostaglandin E2 (PGE2), IL-1beta, and IL-6 was assayed by Western blot analysis and enzyme-linked immunosorbent assay. Gene expression of proMMPs 1 and 3, TIMPs 1 and 2, COX-1 and COX-2, IL-1alpha, IL-1beta, tumor necrosis factor alpha (TNFalpha), and IL-6 was also monitored by Northern blot analysis and reverse transcriptase-polymerase chain reaction.
Triptolide suppressed the IL-1alpha-induced production of proMMPs 1 and 3 and decreased their messenger RNA levels in human synovial fibroblasts. In contrast, the IL-1alpha-induced gene expression and production of TIMPs 1 and 2 were further augmented by triptolide in the synovial cells. Triptolide also inhibited the IL-1alpha-induced production of PGE2 by selectively suppressing the gene expression and production of COX-2, but not those of COX-1. In addition, triptolide suppressed the LPS-induced production of PGE2 in mouse macrophages. Furthermore, the gene expression of IL-1alpha, IL-1beta, TNFalpha, and IL-6, as well as the production of IL-1beta and IL-6, were inhibited by triptolide in the LPS-treated mouse macrophages.
We have demonstrated for the first time that the therapeutic effects of TWHF in RA are due in part to the novel chondroprotective effect of triptolide via the direct suppression of the production of proMMPs 1 and 3 and the simultaneous up-regulation of TIMPs in IL-1-treated synovial fibroblasts. Triptolide's interference with gene expression of proinflammatory cytokines and its known inhibitory effects on PGE2 production are also probably very effective.
在中国，中药雷公藤（Tripterygium wilfordii Hook. f., TWHF）的多种提取物据报道对类风湿关节炎（RA）具有治疗效果，但其作用机制尚不清楚。我们研究了雷公藤中的二萜三环氧化物雷公藤内酯醇对人滑膜成纤维细胞和J774A.1小鼠巨噬细胞中前基质金属蛋白酶1（proMMP-1；或原胶原酶1或前间质胶原酶1）、proMMP-3（或原基质溶素1）、金属蛋白酶组织抑制剂（TIMPs）以及促炎细胞因子产生的影响。
在有或无雷公藤内酯醇的情况下，用人白细胞介素-1α（IL-1α）或脂多糖（LPS）培养人滑膜成纤维细胞和小鼠巨噬细胞。通过蛋白质印迹分析和酶联免疫吸附测定法检测proMMPs 1和3、TIMPs 1和2、环氧化酶1（COX-1）和COX-2、前列腺素E2（PGE2）、IL-1β和IL-6的产生。还通过Northern印迹分析和逆转录-聚合酶链反应监测proMMPs 1和3、TIMPs 1和2、COX-1和COX-2、IL-1α、IL-1β、肿瘤坏死因子α（TNFα）和IL-6的基因表达。
雷公藤内酯醇抑制IL-1α诱导的人滑膜成纤维细胞中proMMPs 1和3的产生，并降低其信使核糖核酸水平。相反，雷公藤内酯醇在滑膜细胞中进一步增强了IL-1α诱导的TIMPs 1和2的基因表达和产生。雷公藤内酯醇还通过选择性抑制COX-2的基因表达和产生，而非COX-1的表达和产生，来抑制IL-1α诱导的PGE2产生。此外，雷公藤内酯醇抑制小鼠巨噬细胞中LPS诱导的PGE2产生。此外，在LPS处理的小鼠巨噬细胞中，雷公藤内酯醇抑制IL-1α、IL-1β、TNFα和IL-6的基因表达以及IL-1β和IL-6的产生。
我们首次证明，TWHF在RA中的治疗作用部分归因于雷公藤内酯醇通过直接抑制proMMPs 1和3的产生以及同时上调IL-1处理的滑膜成纤维细胞中TIMPs的产生而产生的新型软骨保护作用。雷公藤内酯醇对促炎细胞因子基因表达的干扰及其对PGE2产生的已知抑制作用可能也非常有效。
