Idris Aymen I, Ralston Stuart H, van't Hof Rob J
Rheumatic Diseases Unit, Molecular Medicine Centre, University of Edinburgh, General Western Hospital, Edinburgh, UK.
Eur J Pharmacol. 2009 Jan 14;602(2-3):215-22. doi: 10.1016/j.ejphar.2008.11.023. Epub 2008 Nov 19.
We have previously shown that the nitrosylated flurbiprofen derivative HCT1026 inhibits bone resorption, both in vivo and in vitro, and that its mechanism of action is independent of nitric oxide release and prostaglandin synthesis inhibition. Here we describe the effects of HCT1026 on osteoclast formation, activity, survival and cell signalling in vitro. HCT1026 strongly inhibited osteoclast formation, activity and survival in murine osteoclast cultures, whereas macrophages and osteoblasts were unaffected. HCT1026 induced osteoclast apoptosis, and this was partially prevented by increasing the concentration of receptor activator of nuclear factor kappa B ligand (RANKL). This suggests that HCT1026 inhibits bone resorption by inhibiting the effects of RANKL. In agreement with this we found that HCT1026 inhibited RANKL-induced activation of the nuclear factor kappa B (NFkappaB) and extracellular signal-regulated kinase (ERK) pathways in both osteoclast and macrophage cultures, whereas its parent compound flurbiprofen did not. In addition, HCT1026 also inhibited tumor necrosis factor (TNF)-, interleukin-1 (IL1)- and LPS-induced signalling, but not macrophage colony stimulating factor induced signalling. The pathways that are inhibited by HCT1026 all share a similar kinase complex upstream of the NFkappaB and ERK pathways, and this is the most likely target for the actions of HCT1026. Although the rationale for the modification of flurbiprofen with a nitric oxide donor group was to prevent gastro-intestinal toxicity, the resulting compound HCT1026 gained unexpected additional cytokine-inhibitory properties. As RANKL, TNF and IL1 are all important mediators of inflammation and joint destruction, compounds like HCT1026 could represent a novel class of anti-inflammatory compounds.
我们之前已经表明，亚硝基化氟比洛芬衍生物HCT1026在体内和体外均能抑制骨吸收，并且其作用机制独立于一氧化氮释放和前列腺素合成抑制。在此，我们描述了HCT1026在体外对破骨细胞形成、活性、存活及细胞信号传导的影响。HCT1026强烈抑制小鼠破骨细胞培养物中的破骨细胞形成、活性和存活，而巨噬细胞和成骨细胞则不受影响。HCT1026诱导破骨细胞凋亡，增加核因子κB配体（RANKL）的浓度可部分阻止这种凋亡。这表明HCT1026通过抑制RANKL的作用来抑制骨吸收。与此一致的是，我们发现HCT1026在破骨细胞和巨噬细胞培养物中均抑制RANKL诱导的核因子κB（NFκB）和细胞外信号调节激酶（ERK）途径的激活，而其母体化合物氟比洛芬则无此作用。此外，HCT1026还抑制肿瘤坏死因子（TNF）、白细胞介素-1（IL1）和脂多糖诱导的信号传导，但不抑制巨噬细胞集落刺激因子诱导的信号传导。被HCT1026抑制的途径在NFκB和ERK途径上游均共享一个相似的激酶复合物，这很可能是HCT1026作用的靶点。尽管用一氧化氮供体基团修饰氟比洛芬的基本原理是预防胃肠道毒性，但所得化合物HCT1026却获得了意外的额外细胞因子抑制特性。由于RANKL、TNF和IL1都是炎症和关节破坏的重要介质，像HCT1026这样的化合物可能代表一类新型抗炎化合物。
