雷公藤多苷通过PI3K/Akt通路对糖尿病肾病大鼠热休克蛋白90及PGC-1α表达的影响

Tripterygium Glycosides Tablets affect the levels of heat shock protein 90 and PGC-1α in rats with diabetic nephropathy through PI3K/Akt pathway

摘要:

目的 探究雷公藤多甙（TG）通过PI3K/Akt通路对糖尿病肾病（DN）大鼠热休克蛋白90（HPS90）及过氧化物酶体增殖物激活受体-γ共激活因子-1α（PGC-1α）水平的影响。方法 通过腹腔注射链脲佐菌素复制DN大鼠模型，并将其随机分为DN组、DN+TG组和DN+TG+SC79组（每组15只），另取15只健康大鼠作为对照组。TG灌胃剂量为20 mg/kg。大鼠腹膜内注射SC79（0.04 mg/g）以激活PI3K/Akt通路。通过HE染色验证模型复制结果和TG对肾组织的保护作用。生化检测大鼠24 h尿蛋白和肌酐，酶联免疫吸附试验检测炎症因子水平，HE染色观察各组大鼠肾损伤情况，Masson染色观察各组大鼠肾纤维化情况，qRT-PCR和Western blotting 分别检测HPS90和PGC-1α mRNA和蛋白相对表达量。结果 DN组24 h尿蛋白、肌酐、肾组织纤维化面积百分比、p-PI3K/PI3K、p-Akt/Akt、HSP90 mRNA和蛋白相对表达量、IL-1β及IL-6高于对照组（P <0.05），PGC-1α mRNA和蛋白相对表达量低于对照组（P <0.05）；DN+TG组24 h尿蛋白、肌酐、肾组织纤维化面积百分比、p-PI3K/PI3K、p-Akt/Akt、HSP90 mRNA和蛋白相对表达量、IL-1β及IL-6低于DN组（P <0.05），PGC-1α mRNA和蛋白相对表达量高于DN组（P <0.05）。DN+TG+SC79组24 h尿蛋白、肌酐、肾组织纤维化面积百分比、p-PI3K/PI3K、p-Akt/Akt、HSP90 mRNA和蛋白相对表达量、IL-1β及IL-6高于DN+TG组（P <0.05），PGC-1α mRNA和蛋白相对表达量低于DN+TG组（P <0.05）。结论 TG可以通过抑制PI3K/Akt通路抑制HSP90的转录和翻译，从而促进PGC-1α的表达，并发挥抗炎和抗纤维化作用，从而缓解DN。

Abstract:

Objective To explore the effects of Tripterygium Glycosides (TG) Tablets on the levels of heat shock protein 90 (HPS90) and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) in diabetic nephropathy (DN) rats and the roles of PI3K/Akt pathway.Methods The DN model was established by intraperitoneal injection of streptozotocin. A total of 45 DN rats were divided into DN group (n = 15), DN+TG group (n = 15) and DN+TG+SC79 group (n = 15), and another 15 healthy rats were selected as the control group. TG were administered intragastrically at a dose of 20 mg/kg, and SC79 (0.04 mg/g) was injected intraperitoneally to activate the PI3K/Akt pathway. The HE staining was applied to determine whether the DN model was successfully established and to assess the protective effects of TG on the kidney. The renal function, the area percentage of kidney fibrosis, the mRNA and protein levels of molecules associated with PI3K/Akt pathway, HPS90 and PGC-1α, and inflammatory factor levels in each group were detected.Results The 24-hour urine protein, creatinine, the area percentage of kidney fibrosis, the mRNA and protein levels of p-PI3K/PI3K, p-Akt/Akt and HSP90, and the levels of IL-1β and IL-6 in the DN group were higher than those in the control group (P < 0.05), while the mRNA and protein levels of PGC-1α were lower in the DN group than those in the control group (P < 0.05). The 24-hour urine protein, creatinine, the area percentage of kidney fibrosis, the mRNA and protein levels of p-PI3K/PI3K, p-Akt/Akt and HSP90, and the levels of IL-1β and IL-6 in the DN+TG group were lower than those in the DN group (P < 0.05), while the mRNA and protein levels of PGC-1α were higher in the DN+TG group than those in the DN group (P < 0.05). In addition, the 24-hour urine protein, creatinine, the area percentage of kidney fibrosis, the mRNA and protein levels of p-PI3K/PI3K, p-Akt/Akt and HSP90, and the levels of IL-1β and IL-6 were higher, and the mRNA and protein levels of PGC-1α were lower in the DN+TG+SC79 group compared with those in the DN+TG group (P < 0.05).Conclusions TG can downregulate the transcription and translation of HSP90 by inhibiting the PI3K/Akt pathway and further promote the expression of PGC-1α, through which TG exert anti-inflammatory and anti-fibrotic effects, thereby alleviating DN.