系统性红斑狼疮初发患者外周血中维生素D及其受体mRNA的水平和意义

The significance of the vitamin D and vitamin D receptor in the initial systemic lupus erythematosus patients

目的①检测初发系统性红斑狼疮（SLE）患者外周血中维生素D内分泌系统的水平，探讨维生素D内分泌系统在SLE发病中的作用。②分析维生素D内分泌系统水平与SLE患者骨密度和病情活动程度的关系。方法选择初发SLE患者43例，健康对照组44名，用酶联免疫吸附试验（ELISA）检测患者外周血浆中25羟基维生素D3（250HD3）和1，25-二羟基D3[1，25（OH）2D3]的水平，利用实时定量反转录一聚合酶链反应（RT—PCR）法检测患者外周血维生素D受体（VDR）表达水平。双能X线分别检测患者腰椎（L1-4）和股骨近端2个部位的骨密度，根据SLE疾病活动指数（SLEDAI）评分评估SLE病情活动程度。采用统计学单因素分析分别检验250HD，、1，25（OH）2D3和VDR基因mRNA表达水平与SLE患者骨密度和病情活动程度的关系。结果初发SLE患者250HD3和1，25（OH）2D3激素水平与健康对照组比较，差异有统计学意义（P均〈0．01）；初发SLE患者组与健康对照组比较，VDR基因mRNA表达水平的差异有统计学意义（P〈0．01）；SLE患者2个部位的骨密度均低于健康对照组，且两组问的差异有统计学意义（P〈0．05），SLE患者组骨量异常的发生率为35％，骨量异常与骨量健康对照组之间250HD3、1，25（OH）2D3激素水平及VDR基因mRNA表达水平的差异无统计学意义（P〉0．05）；250HD，、1，25（OH）2D3激素水平和VDR基因mRNA表达水平与SLE患者骨密度的情况不存在相关性（r=0．187，P〉0．05；r=0．172，P〉0．05；r=0．287，P〉0．05），它们与SLE患者的病情活动度之间也不存在相关性（r=0．054，P〉0．05；r=0．190，19〉0．05；r=0．046，P〉0．05）。结论SLE患者维生素D激素的水平及VDR基因的表达异常提示维生素D内分泌系统可能参与了SLE的发病，但与SLE患者骨量异常的发生和SLE病情活动度不存在相关性。

Objective ① To investigate the level of the vitamin D endocrine system in peripheral blood of patients with systemic lupus erythematosns （SLE） and to study its effect on SLE. ② To analyze its relationships with bone mineral density （BMD） and the disease activity respectively. Methods The level of the 25-hydroxylate vitamin D3 （25OHD3） and 1,25-dihydroxyvitamin D3 [ 1,25 （OH）D3 ] in plasma from 43 SLE patients and 44 normal controls were detected by enzyme linked immunosorbent assay. Vitamin D receptor （VDR） gene expression was determinied by real-time PCR in peripheral blood. BMD measurements in the lumbar spine （L1-4） and left proximal femur （femoral neck ） were performed using dual X-ray absorptiomctry before treatment. The relationship between the vitamin D endocrine system and the bone mass were studied. We also discussed the relationship between the vitamin D endocrine system and the disease activity. Results The levels of 25OHD3 and 1,25 （OH）2D3 were lower in the initial SLE patients than normal controls （P〈0.01, P〈0.01 ）. The expressions of VDR gene were significantly increased in initial SLE compared with normal controls （P〈0.01）. The initial SLE patients had significantly lower BMD values, and higher frequency of osteopenia （35%） at both sites of measurement compared with matched healthy controls （P〈0.01）. The initial SLE patients were divided into two groups by BMD, abnormal group and normal group. There were nodifferences in 25OHD3, 1,25（OH）D3 and VDR gene expression （P〉0.05）. There was no correlation between the vitamin D endocrine system and BMD in initial SLE patients. There was no correlation between the vitamin D endocrine system and the disease activity either. Conclusion Vitamin D endocrine system may play an important role in SLE, but the level of VDR gene is not correlated with BMD and disease activity.