Lowin Torsten, Zhu Wentao, Dettmer-Wilde Katja, Straub Rainer H
University Hospital Regensburg, Regensburg, Germany.
Arthritis Rheum. 2012 Dec;64(12):3867-76. doi: 10.1002/art.37684.
In rheumatoid arthritis (RA) synovial fluid, levels of the endocannabinoids anandamide (AEA) and 2-arachidonylglycerol are elevated. Since synovial fibroblasts (SFs) possess all of the enzymes necessary for endocannabinoid synthesis, it is likely that these cells contribute significantly to elevated endocannabinoid levels. While glucocorticoids initiate endocannabinoid synthesis in neurons, this study was undertaken to test whether cortisol also regulates endocannabinoid levels in mesenchymal cells such as SFs, and whether this interferes with integrin-mediated adhesion.
Adhesion was determined in 1-minute intervals over 60 minutes using an xCELLigence system. Slopes from individual treatment groups were averaged and compared to the control. Fatty acid amide hydrolase (FAAH) and cyclooxygenase 2 (COX-2) were detected by immunocytochemistry, and AEA was detected by mass spectrometry.
Cortisol increased the adhesion of RASFs and osteoarthritis SFs with a maximum of 200% at both 10(-7) M and 10(-8) M. When cortisol was administered together with either cannabinoid receptor 1 (CB(1) ) antagonist (rimonabant; 100 nM), CB(2) antagonist (JTE907; 100 nM), transient receptor potential vanilloid channel 1 (TRPV-1) antagonist (capsazepine; 1 μM), FAAH inhibitor, or COX-2 inhibitor, adhesion was reduced below the level in controls. Concomitant inhibition of FAAH and COX-2 reversed these effects. Mass spectrometry revealed the presence of AEA in SFs.
Our findings indicate that glucocorticoid-induced adhesion is dependent on CB(1) /CB(2) /TRPV-1 activation. Since AEA is produced in SFs, this endocannabinoid is the most likely candidate to mediate these effects. Since AEA levels are regulated by COX-2 and FAAH, inhibition of both enzymes along with low-dose glucocorticoids may provide a therapeutic option to maximally boost the endocannabinoid system in RA, with possible beneficial effects.
在类风湿关节炎（RA）滑液中，内源性大麻素花生四烯酸乙醇胺（AEA）和2-花生四烯酸甘油的水平升高。由于滑膜成纤维细胞（SFs）具备内源性大麻素合成所需的所有酶，这些细胞很可能对升高的内源性大麻素水平有显著贡献。虽然糖皮质激素可在神经元中启动内源性大麻素合成，但本研究旨在测试皮质醇是否也调节间充质细胞（如SFs）中的内源性大麻素水平，以及这是否会干扰整合素介导的黏附。
使用xCELLigence系统在60分钟内每隔1分钟测定一次黏附情况。将各个治疗组的斜率进行平均并与对照组比较。通过免疫细胞化学检测脂肪酸酰胺水解酶（FAAH）和环氧合酶2（COX-2），通过质谱检测AEA。
皮质醇增加了RA滑膜成纤维细胞（RASFs）和骨关节炎滑膜成纤维细胞的黏附，在10⁻⁷ M和10⁻⁸ M时最大增加200%。当皮质醇与大麻素受体1（CB₁）拮抗剂（利莫那班；100 nM）、CB₂拮抗剂（JTE907；100 nM）、瞬时受体电位香草酸通道1（TRPV-1）拮抗剂（辣椒素；1 μM）、FAAH抑制剂或COX-2抑制剂一起给药时，黏附降低至低于对照组水平。同时抑制FAAH和COX-2可逆转这些作用。质谱分析显示SFs中存在AEA。
我们的研究结果表明，糖皮质激素诱导的黏附依赖于CB₁/CB₂/TRPV-1激活。由于AEA在SFs中产生，这种内源性大麻素最有可能介导这些作用。由于AEA水平受COX-2和FAAH调节，同时抑制这两种酶以及低剂量糖皮质激素可能提供一种治疗选择，以最大程度地增强RA中的内源性大麻素系统，可能具有有益效果。
