糖蛋白130小分子抑制剂SC144对单侧输尿管梗阻小鼠肾间质纤维化的影响

Effect of GP130 small molecular inhibitor SC144 on renal interstitial fibrosis in mice with unilateral ureteral obstruction

目的·动态观察糖蛋白130小分子抑制剂SC144对单侧输尿管梗阻(unilateral ureteral obstruction,UUO)小鼠肾组织细胞外基质堆积和Janus蛋白酪氨酸激酶2(Janus kinase 2,JAK2)/信号转导与转录激活因子3(signal transduction and activator of transcription 3,STAT3)信号转导通路(简称JAK2/STAT3信号通路)的影响,探讨SC144防治肾间质纤维化的可能机制。方法·将18只雌性BALB/c小鼠分为3组:假手术组、模型对照组和SC144干预组。于造模后第14日,用苏木精-伊红染色(hematoxylineosin staining,H-E染色)、Masson染色观察肾组织学形态改变,免疫组织化学检测肾脏巨噬细胞浸润和α-平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)表达,real-time PCR检测Ⅰ型/Ⅳ型胶原、单核细胞趋化蛋白-1(monocyte chemoattractant protein-1,MCP-1)、转化生长因子-β(transforming growth factor-β,TGF-β)的mRNA水平,Western blotting检测肾组织JAK2、STAT3的表达和磷酸化水平。结果·SC144干预组肾小管间质损伤程度有明显减轻趋势(H-E染色,P=0.052;Masson染色,P=0.063);肾组织内纤维化指标α-SMA、Ⅰ型/Ⅳ型胶原和TGF-β的mRNA表达下降,与模型对照组相比差异具有统计学意义(均P<0.05)。纤维化信号通路的JAK2和STAT3的磷酸化水平较模型对照组下降(均P<0.05)。结论·在小鼠UUO模型中,小分子抑制剂SC144能抑制α-SMA的活化及STAT3的磷酸化,通过JAK2/STAT3信号通路减轻肾小管上皮间质转化、减少细胞外基质表达,具有延缓UUO小鼠肾间质纤维化进程的作用。

Objective·To investigate the effect of glycoprotein 130(GP130)inhibitor SC144 on extracellular matrix accumulation and JAK2/STAT3 signaling pathway in unilateral ureteral obstruction(UUO)mouse model,and explore its mechanism.Methods·Eighteen female BALB/c mice were randomly divided into 3 groups i.e.sham group,UUO group and SC144 group.All mice were sacrificed at day 14 and kidneys were harvested for further analysis.The changes of renal tissue morphology and pathology were observed by H-E and Masson staining.The expression ofα-smooth muscle actin(α-SMA)and infiltration of macrophage cells were assayed by immunohistochemical staining.The levels of collagen-I,collagen-IV,monocyte chemoattractant protein-1(MCP-1),transforming growth factor-β(TGF-β)mRNA were analyzed by real-time PCR.The activation of JAK2 and STAT3 was measured by Western blotting.Results·There was a trend toward decreased renal tubular lesion and renal interstitial fibrosis in SC144 group(H-E,P=0.052;Masson,P=0.063).SC144 significantly inhibited the levels ofα-SMA,type I/type IV collagen and TGF-βmRNA(all P<0.05).Compared with UUO group,the phosphorylation levels of JAK2 and STAT3 were significantly decreased in SC144 group(both P<0.05).Conclusion·The treatment of UUO mouse model with SC144 can inhibit the activation ofα-SMA,attenuate the phosphorylation of STAT3,reduce extracellular matrix protein deposition following injury and renal tubular epithelial-mesenchymal transition(EMT)via JAK2/STAT3 signaling pathway,indicating its potential in attenuating interstitial fibrosis in obstructive nephropathy.