小鼠胶原诱导性关节炎的严重程度与CYP7B活性增加相关：白细胞介素-1β增强脱氢表雄酮代谢。

Severity of murine collagen-induced arthritis correlates with increased CYP7B activity: enhancement of dehydroepiandrosterone metabolism by interleukin-1beta.

作者信息

Dulos John, Verbraak Evert, Bagchus Wilma M, Boots Annemieke M H, Kaptein Allard

机构信息

Organon NV, Oss, The Netherlands.

出版信息

Arthritis Rheum. 2004 Oct;50(10):3346-53. doi: 10.1002/art.20509.

DOI:10.1002/art.20509

PMID:15476247

Abstract

OBJECTIVE

The endogenous steroid dehydroepiandrosterone (DHEA) has been reported to play a role in rheumatoid arthritis (RA). DHEA is metabolized by the P450 enzyme CYP7B into 7alpha-OH-DHEA, which has immunostimulating properties. This study was undertaken to investigate the putative role of CYP7B in arthritis using murine collagen-induced arthritis (CIA), an interleukin-1beta (IL-1beta)-dependent model.

METHODS

DBA/1J mice were immunized and administered a booster with type II collagen. The presence of 7alpha-OH-DHEA was determined in both arthritic and nonarthritic joints and the serum of CIA mice by radioimmunoassay. CYP7B messenger RNA (mRNA) expression was analyzed in synovial biopsy samples, and in fibroblast-like synoviocytes (FLS) isolated from these synovial biopsy samples, by reverse transcriptase-polymerase chain reaction (RT-PCR). In addition, the regulatory role of IL-1beta on CYP7B activity in FLS was determined using RT-PCR, Western blotting, and high-performance liquid chromatography.

RESULTS

In knee joint synovial biopsy samples from arthritic mice, 7alpha-OH-DHEA levels were 5-fold higher than in nonarthritic mice. Elevated levels of 7alpha-OH-DHEA were accompanied by an increase in CYP7B mRNA expression and were positively correlated with disease severity. In serum, no differences in 7alpha-OH-DHEA levels were observed between arthritic and nonarthritic mice. Incubation of FLS with IL-1beta resulted in a dose-dependent increase in 7alpha-OH-DHEA formation. In addition, IL-1beta enhanced CYP7B mRNA and CYP7B protein levels in FLS.

CONCLUSION

Disease progression in CIA is correlated with enhanced CYP7B activity, which leads to locally enhanced 7alpha-OH-DHEA levels. Elevated IL-1beta levels within the arthritic joint may regulate this increase in CYP7B activity.

摘要

目的

内源性甾体脱氢表雄酮（DHEA）据报道在类风湿关节炎（RA）中发挥作用。DHEA 经细胞色素 P450 酶 CYP7B 代谢生成具有免疫刺激特性的 7α-羟基脱氢表雄酮（7α-OH-DHEA）。本研究采用白细胞介素-1β（IL-1β）依赖的小鼠胶原诱导性关节炎（CIA）模型，旨在探讨 CYP7B 在关节炎中的假定作用。

方法

用 II 型胶原对 DBA/1J 小鼠进行免疫并给予加强免疫。通过放射免疫分析法测定 CIA 小鼠关节炎关节和非关节炎关节以及血清中 7α-OH-DHEA 的存在情况。通过逆转录聚合酶链反应（RT-PCR）分析滑膜活检样本以及从这些滑膜活检样本中分离出的成纤维样滑膜细胞（FLS）中 CYP7B 信使核糖核酸（mRNA）的表达。此外，使用 RT-PCR、蛋白质印迹法和高效液相色谱法确定 IL-1β 对 FLS 中 CYP7B 活性的调节作用。

结果

在关节炎小鼠的膝关节滑膜活检样本中，7α-OH-DHEA 水平比非关节炎小鼠高 5 倍。7α-OH-DHEA 水平升高伴随 CYP7B mRNA 表达增加，且与疾病严重程度呈正相关。在血清中，关节炎小鼠和非关节炎小鼠之间未观察到 7α-OH-DHEA 水平的差异。用 IL-1β 孵育 FLS 导致 7α-OH-DHEA 生成呈剂量依赖性增加。此外，IL-1β 增强了 FLS 中 CYP7B mRNA 和 CYP7B 蛋白水平。