靶向STAT3通过调控糖酵解及间皮间充质转分化改善腹膜透析相关腹膜纤维化

Targeting STAT3 alleviates peritoneal fibrosis by regulating glycolysis and mesothelial-mesenchymal transition

目的研究高糖对人腹膜间皮细胞系(HMrSV5)间皮-间充质转化(MMT)的影响及机制,以及药理阻断信号转导和转录激活因子(STAT3)对大鼠腹膜的保护作用。方法将动物分为3组:假手术组(Sham组)、模型组和STAT3抑制剂组。在大鼠背侧皮肤下手术植入微型腹膜透析导管,每日注射高糖透析液诱导大鼠腹膜纤维化模型。10周后,苏木精-伊红(HE)染色观察腹膜组织病理改变,免疫组化方法检测腹膜组织转化生长因子-β1(TGF-β1)的表达。模拟高糖微环境对HMrSV5进行细胞培养,转染si-STAT3,Western blot方法检测STAT3蛋白和磷酸化水平及糖酵解相关代谢酶6-磷酸果糖-2-激酶/果糖-2,6-双磷酸酶-3(PFKFB3)、乳酸脱氢酶A(LDHA)的表达。结果HE染色显示STAT3抑制剂(BP-1-102)可抑制高糖透析大鼠的腹膜下组织增厚及血管增生。模型组大鼠腹膜组织TGF-β1蛋白表达显著高于假手术组,STAT3抑制剂组大鼠腹膜TGF-β1蛋白表达显著低于模型组(P<0.05)。与对照组相比,高糖诱导HMrSV5细胞STAT3激活,以及α平滑肌肌动蛋白(α-SMA)的上调和E-钙黏蛋白(E-cadherin)下调(P<0.05)。此外,高糖处理导致间皮细胞糖酵解相关代谢酶(PFKFB3、LDHA)的表达增加(P<0.05)。si-STAT3能有效抑制高糖诱导的间皮细胞STAT3活化,降低高糖诱导的PFKFB3、LDHA和α-SMA高表达,同时升高E-cadherin水平(P<0.05)。结论STAT3信号通路参与高糖诱导的HMrSV5过度糖酵解和MMT的发生,靶向STAT3有助于减轻大鼠腹膜透析液诱导的腹膜纤维化和血管新生。

Objective To study the effect and mechanism of high glucose on mesothelial-mesenchymal transition(MMT)of peritoneal mesothelial cells(HMrSV5),and the protective effect of pharmacological blocking of signal transducer and activator of transcription 3(STAT3)on rat peritoneal fibrosis(PF)model.Methods The animals were divided into three groups:the sham group,the model group,and the STAT3 inhibitor group.A miniature peritoneal dialysis catheter was implanted under the dorsal skin of rat and the rat peritoneal fibrosis model was induced by daily injection of high glucose dialysate.After 10 weeks,HE staining was used to evaluate the histology of the peritoneum,and the level of transforming growth factor-β1(TGF-β1)in the peritoneum was measured by immunohistochemistry.HMrSV5 was cultured in high glucose and the optimal stimulation concentration of high glucose was determined by Western blot.High glucose was used to stimulate HMrSV5 after successful transfection with si-STAT3 and Western blot was used to measure the protein level of STAT3,p-STAT3,and the key enzymes of glycol-ysis 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3(PFKFB3)and lactate dehydrogenase A(LDHA).Results HE staining showed that administration of STAT3 inhibitor(BP-1-102)could inhibit the thickening of subperitoneal tissue and the proliferation of vessels in HG dialysis rats.The expression of TGF-β1 in the rats peritoneum of the model group was significantly higher than that in the sham group,and the level of TGF-β1 was markedly lower in the STAT3 inhibitor group compared to the model group(P<0.05).Compared to the control group,high glucose induced the up-regulation ofα-smooth muscle actin(α-SMA),the down-regulation of E-cadherin and STAT3 activation in HMrSV5(P<0.05).Mesothelial cells treated with high glucose also exhibited high expression of the key enzymes of glycolysis(PFKFB3,LDHA)(P<0.05),and si-STAT3 can effectively inhibit the overexpression of PFKFB3 and LDHA induced by high glucose(P<0.05).Conclusion STAT3 is involved in high glucose-induced HMrSV5 hyperglycolysis and MMT,and targeting STAT3 alleviates peritoneal fibrosis and angiogenesis during peritoneal dialysis treatment in rats.