肾特发性草酸钙结石形成与骨桥蛋白的关系

Investigation of association between osteopontin and the formation of idiopathic calcium oxalate stone

目的 观察特发性草酸钙结石（ICS）患者肾组织中骨桥蛋白（OPN） mRNA和蛋白表达水平及尿液中骨桥蛋白（OPN）浓度,探讨OPN在ICS形成中的作用.方法 选取因患肾无功能行肾切除术ICS患者肾组织标本34例为实验组;同期行根治性肾切除术患者远癌正常肾组织标本38例作为对照组;选取19例健康体检正常人为正常组.实时定量聚合酶链反应（Real-time PCR）法、Western blot法及免疫组织化学法分别检测实验组和对照组肾组织中OPN mRNA及蛋白的表达;酶联免疫吸附实验（ELISA）法测定实验组、对照组和正常组尿液中OPN浓度.结果 实验组肾组织OPN mRNA及蛋白相对表达量（2.040±1.200、0.776±0.071）均高于对照组（2.590±0.910、0.449±0.085,P＜0.05）;但实验组尿液中OPN蛋白浓度[（1.052±0.229） mg/L]均低于对照组[（1.579±0.256） mg/L）]和正常组[（1.498±0.155） mg/L,P＜0.05].结论 肾小管上皮细胞OPN mRNA和蛋白的过表达及尿液中OPN浓度的降低可能是ICS患者肾结石形成的重要原因.

Objective To investigate the role of osteopontin （OPN） in the formation of idiopathic calcium oxalate stone （ICS） by detecting OPN transcription and translation level in the renal tissue and the urine concentration of OPN in ICS patients.Methods From January 2013 to January 2014,34 cases of no-function kidneys were collected after the nephrectomy as the case group,38 cases of normal renal tissuesfar away from the tumor as the control group after the radical nephrectomy,and 19 healthy persons as the normal group in our hospital.The expression of OPN mRNA and protein in the tissues of kidney were detected by real-time quantitative polymerase chain reaction （Real-time PCR）,Western blotting and immunohistochemistry,respectively.The concentration of OPN in the urine of the groups was measured by enzyme-linked immunosorbent assay.Results The levels of OPN mRNA and protein in the renal tissues of the case group （2.040 ± 1.200,0.776 ± 0.071） were higher than that of control group （2.590 ± 0.910,0.449 ±0.085,P ＜0.05）.The concentration of OPN in the urine of the patients in the case group [（1.052 ±0.229） mg/L] was lower than that of control group [（1.579 ± 0.256） mg/L] and normal group [（1.498 ± 0.155） mg/L,P ＜ 0.05].Conclusion The over-expression of OPN in the renal tissue and the low concentration of OPN in the urine may play an important role in the formation of ICS.