BAY 41-2272防治大鼠Thy-1肾炎的实验研究

Protective Effect of BAY 41-2272 In Thy-1-induced Glomerulosclerosis of Rats

目的:观察比较BAY41-2272和己酮可可碱(PTX)这两种增强环磷酸鸟苷(cGMP)活性的物质对大鼠Thy-1诱导的进展性肾病模型的疗效,探讨肾纤维化治疗的新途径。方法:成功诱导Thy-1肾炎后,将大鼠分为四组:即肾纤维化组(RF组)、BAY 41-2272治疗组、PTX治疗组和对照组。治疗15周后,分别检测各组大鼠血清肌酐和尿蛋白排泄量,肾组织病理和免疫组化方法检测肾小球/小管间质基质堆积程度和ED1/PCNA阳性细胞数,检测肾小球和皮质转化生长因子TGF-β1、纤粘蛋白(fi- bronectin)、基质金属蛋白酶抑制物(TIMP-1)等蛋白能表达水平,ELISA方法检测肾小球/小管间质细胞的基础、刺激后cGMP水平。RT-PCR方法检测内皮细胞一氧化氮合成酶、α1/β1可溶性鸟苷酸环化酶mRNA水平。结果:观察结束时,BAY41-2272显著降低大鼠尿蛋白排泄和血肌酐水平,显著减轻肾小球/小管间质基质堆积程度,降低巨噬细胞浸润数目和TGF-β1、fibronectin表达水平,而PTX治疗仅产生轻微的变化。肾纤维化组大鼠的小管间质sGC mRNA、NO刺激的cGMP水平显著高于对照组,而肾小球的则较对照组降低;BAY41-2272治疗后肾小球/小管间质sGC mRNA、刺激后cGMP水平可显著提高,而PTX治疗的只有轻度提高而无统计学意义。结论:BAY41-2272治疗可显著改善肾组织NO-cGMP信号通路转导和cGMP的活性,可有效的延缓肾纤维化的进展,而PTX疗效则相对很弱。采用BAY41-2272提高cGMP活性的方案可能为肾纤维化提供新颖、极具前景的治疗策略。

Objective： To investigate the effects of two different cGMP-enhancing agents, BAY 41-2272 ＆ pentoxyfilline （PTX）, in a progressive anti-Thy-1-induced glomerulosclerosis model of rats, and to unravel a novel and effective approach for renal fibrotic disease. Methods： After successful induction of Thy-1 renal disease, the rats were divided into 4 groups： Renal fibrosis group （RF）; RF＋BAY 41-2272 group; RF＋PTX group and untreated control group. After 15 weeks＇ survey, urine protein excretion （UPE）, plasma creatinine （Cr） were detected. Relative degree of glomerular/tubulointerstitial matrix expansion and ED1/PCNA positive cells were examined by renal histology and immunohistochemistry . Glomerular and cortical protein expression of TGF-β1, fibronectin and TIMP-1 were analyzed, basal and NO-stimulated cGMP productions were measured by ELISA respectively. Finally, the cortical mRNA expression of endothelial NO synthase （eNOS）, α1/β1-soluble guanylate cyclase （sGC） were quantified by RT-PCR. Results： This study showed that BAY 41-2272 markedly reduced UPE and Cr levels as well as glomerular/tubulointerstitial matrix deposition, expression of TGF-β1, fibronectin and macrophage infiltration; whereas PTX had slightly moderate and nonsignificant renoprotective changes. Tubulointerstitial expressions of sGC mRNA and NO-induced cGMP production were increased in RF group; the glomerular ones were reduced compared with control group. Conclusion： BAY 41-2272 treatment significantly improved renal NO-cGMP signaling and increased cGMP activity; moreover, it can retard progression of renal fibrosis, whereas PTX therapy was only moderately effective. The findings suggested that enhancing renal eGMP activity by BAY 41-2272 may provide a novel and prospective remedy for progressive fibrotic renal disease.