目的 探究天花粉蛋白（trichosanthin，TCS）治疗糖尿病肾病（diabetic kidney disease，DKD）的作用及机制。方法 将30只SD大鼠随机分为对照组、模型组和TCS（20 μg/kg）组，造模后给予TCS干预9周。实验过程中监测大鼠血糖和体质量变化；给药结束后，通过苏木素-伊红（HE）和Masson染色观察肾脏结构改变；检测血清胰岛素和血脂水平；检测尿液白蛋白和血清肌酐、尿素氮水平以评价肾脏功能；通过非靶向代谢组学分析对照组、模型组和TCS组大鼠尿液代谢物差异；采用Western blotting检测大鼠肾组织α-平滑肌肌动蛋白（α-smooth muscle actin‌，α-SMA）、B细胞淋巴瘤-2（B-cell lymphoma-2，Bcl-2）‌、腺苷酸活化蛋白激酶（adenosine 5′-monophosphate-activated protein kinase，AMPK）、p-AMPK和芳香烃受体（aryl hydrocarbon receptor，AHR）的蛋白表达。体外以高糖诱导的HK-2细胞为研究对象，通过免疫荧光分析TCS对高糖诱导的HK-2细胞内ROS水平及凋亡的影响，通过Western blotting分析TCS对高糖诱导的HK-2细胞α-SMA、Bcl-2、AMPK、p-AMPK和AhR蛋白表达的影响。结果 与模型组比较，TCS组大鼠肾脏中空泡明显减少，炎症减轻，胶原沉积显著减少；TCS可显著降低DKD大鼠血糖（P＜0.05、0.001），增加体质量（P＜0.05、0.01、0.001），调控胰岛素、血脂和肾功能相关指标水平（P＜0.001），保护肾脏滤过功能。大鼠尿液非靶向代谢组学分析结果显示，色氨酸代谢为TCS治疗DKD的主要作用途径。细胞实验结果显示，高糖诱导后细胞凋亡增加，而25μg/mL TCS能够明显抑制细胞内ROS水平和细胞凋亡。Western blotting结果显示，TCS显著下调DKD大鼠肾组织和高糖诱导的HK-2细胞α-SMA、AhR和p-AMPK/AMPK表达（P＜0.01、0.001），显著上调Bcl-2蛋白表达（P＜0.05、0.001）。结论 TCS可以通过调节AhR介导的色氨酸代谢途径改善凋亡，从而治疗DKD。

Objective To explore the effect and mechanism of trichosanthin (TCS) in treatment of diabetic kidney disease (DKD).Methods A total of 30 SD rats were randomly divided into control group, model group and TCS (20 μg/kg) group. After modeling, TCS intervention was given for nine weeks. The changes in blood glucose and body weight of rats were monitored during the experimental process. After administration, changes in renal structure were observed by hematoxylin-eosin (HE) and Masson staining. Levels of insulin and lipid in serum were detected. Levels of albumin in urine, serum creatinine and blood urea nitrogen were detected to evaluate renal function. The differences in urinary metabolites among control group, model group and TCS group rats were analyzed through non-targeted metabolomics analysis. Western blotting was used to detect the protein expressions of α-smooth muscle actin (α-SMA), B-cell lymphoma-2 (Bcl-2), adenosine 5′-pyrophosphate activated protein kinase (AMPK), p-AMPK and aryl hydrocarbon receptor (AHR) in kidney tissue of rats. High glucose-induced HK-2 cells were used as the research object in vitro, the effect of TCS on ROS level and apoptosis in high glucose-induced HK-2 cells was analyzed by immunofluorescence, and the effect of TCS on expressions of α-SMA, Bcl-2, AMPK, p-AMPK and AhR proteins in high glucose-induced HK-2 cells was analyzed by Western blotting.Results Compared with model group, TCS group showed a significant reduction in renal vacuoles, inflammation and collagen deposition in rats. TCS could significantly reduce blood glucose (P < 0.05, 0.001), increase body weight (P < 0.05, 0.01, 0.001), regulate insulin, blood lipids and renal function related indicators (P < 0.001), and protect renal filtration function in DKD rats. The non-targeted metabolomics analysis of rat urine showed that tryptophan metabolism was the main pathway of TCS in treatment of DKD. The cell experiment results showed that high glucose induced cell apoptosis increased, while 25 μg/mL TCS could significantly inhibit intracellular ROS level and cell apoptosis. Western blotting results showed that TCS significantly down-regulated the expressions of α-SMA, AhR and p-AMPK/AMPK in kidney tissue of DKD rats and high glucose-induced HK-2 cells (P < 0.01, 0.001), and significantly up-regulated the expression of Bcl-2 protein (P < 0.05, 0.001).Conclusion TCS can improve apoptosis and treat DKD by regulating AhR mediated tryptophan metabolism pathway.

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山东省重大科技创新工程项目（2021CXGC010508）；山东省自然科学基金资助项目（ZR2021LZY030）