IgA 肾病大鼠尿维生素D 结合蛋白 与肾脏纤维化关系的研究

Association between urinary vitamin D binding protein and renal fibrosis in rat model of IgA nephropathy

摘要:

目的 测定IgA 肾病大鼠尿维生素D 结合蛋白（VDBP）及肾组织胶原纤维的含量，探讨尿VDBP 与 IgA 肾病肾脏纤维化的关系。方法 选取20 只SD 大鼠随机分为对照组和模型组。模型组复制IgA 肾病模型，以正常 SD 大鼠为对照组。在实验第10 周末，应用全自动生化分析仪测定各组大鼠尿红细胞、24 h 尿蛋白、肝肾功能指标， 酶联免疫吸附法测定24 h 尿VDBP，半定量分析法计算胶原纤维所占肾组织面积百分比，以观察肾脏纤维化程 度，检测肾组织中转化生长因子β1（TGF-β1）蛋白表达水平，分析该指标之间的关系。结果 模型组大鼠24 h 尿 蛋白（23.44±2.72）mg/24 h、尿VDBP（0.65±0.27）μg/24 h、肾纤维化程度（13.80±6.18）%、TGF-β1 蛋白 表达水平（1.03±0.14）均高于对照组大鼠的尿蛋白（5.44±1.50）mg/24 h、尿VDBP（0.19±0.09）μg/24 h、 肾纤维化（1.23±1.07）%、TGF-β1 蛋白表达水平（0.61±0.14），差异有统计学意义（均P <0.05）。所有实验 动物24 h 尿VDBP 定量与肾组织纤维化程度、TGF-β1 蛋白表达水平、尿蛋白呈正相关（r =0.859、0.908 和 0.567）。结论 24 h 尿VDBP 可作为监测IgA 肾病大鼠肾纤维化的一个无创生物学指标。

Abstract:

Objective To investigate association between urinary vitamin D binding protein (VDBP) and renal fibrosis in rat model of IgA nephropathy (IgA) rats. Methods A total of 20 Sprague-Dawley rats were randomly divided into control group and IgA group. Rats in IgA group were received with bovine serum albumin (BSA), lipopolysaccharide (LPS) and carbon tetrachloride (CCl4). Control group received nothing. At the end of the 10th week, levels of 24-hour urinary protein, 24-hour urinary VDBP, renal function profiles, renal histopathology and TGF-β1 expression in renal tissue were measured. The relationship between these indexes were analyzed. Results In IgA group, Rats experienced significantly increased levels of 24 hour urinary protein, 24 hour urinary VDBP, renal fibrosis and TGF-β1 in IgAN group when compared with control group [(23.44 ± 2.72) vs (5.44 ± 1.50) mg, (0.65 ± 0.27) vs (0.19 ± 0.09) μg/24 h, (13.80 ± 6.18) % vs (1.23 ± 1.07) %, (1.03 ± 0.14) vs (0.61 ± 0.14), P < 0.05,respectively]. The 24-hour urinary VDBP was positively related to 24-hour urinary protein, renal fibrosis and TGF-β1 expression (r = 0.859, 0.908 and 0.567, P < 0.05). Conclusion VDBP is potentially a biomarker of renal fibrosis in IgA rats.