熊果酸通过调节Wnt／β-catenin通路抑制高糖诱导的足细胞上皮间充质转分化  

Ursolic acid inhibits high glucose- induced epithelial mesenchymal transition of podocyte by mediating Wnt/β- catenin signaling pathway

作　　者：李琳[1] 徐莉[1] 范秋灵[1] 汪旭[2] 张艳宁[1] 王力宁[1] 

机构地区：[1]中国医科大学附属第一医院肾内科,沈阳110001 [2]中国医科大学附属第一医院消化内科,沈阳110001

出　　处：《中华肾脏病杂志》2016年第5期365-370,共6页Chinese Journal of Nephrology

基　　金：国家自然科学基金（81270808）;沈阳市科学计划项目（F16-205-1-40）;辽宁省高等学校重大科技平台免疫皮肤病学重点实验室自主创新课题基金（201303）

摘　　要：目的观察高糖诱导足细胞Wnt／β-catenin通路活化及足细胞形态改变，探讨熊果酸保护足细胞损伤的可能机制。方法体外培养足细胞并分为4组：正常糖组（葡萄糖5．5mmol／L）、甘露醇组（葡萄糖5．5mmol／L＋甘露醇19．5mmol／L）、高糖组（葡萄糖25mmol／L）和熊果酸组（葡萄糖25mmol／L＋熊果酸5μmol／L）。倒置相差显微镜检测足细胞形态转化；免疫荧光检测足细胞紧密连结蛋白1（ZO-1）、a平滑肌肌动蛋白（a-SMA）的表达；Western印迹法检测足细胞B连环蛋白（B-catenin）、糖原合成酶激酶3p（GSK3β）的表达；实时定量PCR法检测足细胞Wntl、Wnt3a、Wnt5a、Wnt5b和B-cateninmRNA的表达。结果正常糖组足细胞呈不规则的树枝状，高糖培养下足细胞向鹅卵石、细长状态的间充质细胞形态转化。高糖诱导足细胞后ZO．1蛋白表达下调，a-SMA表达增加，Wnt5a mRNA表达下调，B-cateninmRNA及蛋白表达上调，GSK313蛋白表达下调（均P〈0．05）。相对于高糖组，熊果酸组足细胞发生上皮细胞间充质转化的比例减少，ZO-1蛋白表达增加，a-SMA蛋白表达下降，Wnt5amRNA表达上调，B-cateninmRNA及蛋白表达下调，GSK3β蛋白表达上调（均P〈0．05）。结论熊果酸通过调节Wnt／β-catenin信号通路抑制高糖诱导的足细胞上皮间充质转分化，减轻足细胞损伤。Objective To observe the epithelial mesenchymal transition （EMT） of podocyte induced by high glucose, and to explore the potential protective mechanism of ursolie acid （UA）. Methods The podocytes cultured in vitro were divided into four groups： normal group （glucose 5.5 mmol/L）, mannitol group （glucose 5.5 mmol/L＋mannitol 19.5 mmol/L）, high glucose group （glucose 25 mmol/L） and UA group （glucose 25 mmol/L ＋ UA 5 μmol/L）. Podocyte morphology changes were observed by inverted phase contract microscope. The expression of zonula occludens- 1 （ZO- I） and a-smooth muscle actin （a-SMA） were detected by immunofluorescence. The expressions of β-catenin and glycogen synthesis kinase- 3β （GSK3β） were detected by Western blotting. The expressions of Wntl, Wnt3a, Wnt5a, WntSb and GSK3β were detected by real- time PCR. Results Podocytes showed irregular arborization shape in normal glucose and transited to longer cobblestone-like shape as mesenchyme cell by high glucose culture. Compared with normal group, the expression of ZO-1 protein was down-regulated and the expression of a-SMA was up-regulated by high glucose culture （P 〈 0.05）.The expression of Wnt5a mRNA was down-regulated; 13-catenin mRNA and protein were up-regulated （P 〈 0.05）; and GSK313 protein was down-regulated by high glucose culture （P 〈 0.05）. Compared with high glucose group, ursolic acid inhibited podocyte EMT, up-regulated the expression of ZO-1 protein, WntSa mRNA, GSK3β （P 〈 0.05）, and down-regulated the expressions of α-SMA protein, β-catenin mRNA and protein （P 〈 0.05）. Conclusion Ursolic acid attenuates high glucose induced epithelial mesenchymal transition of podocyte by inhibiting Wnt/13-catenin signaling pathway.

关 键 词：糖尿病肾病 足细胞 熊果酸 细胞转分化 Wnt/β—catenin信号通路 

分 类 号：R587.2[医药卫生—内分泌] R692.9[医药卫生—内科学]