Na Ri-Su, Ma Cong, Liu Qiao-Rui, Wu Li-Ming, Zheng Xu-Lei, Liu Zhi-Wen
Department of Endocrinology, Shanghai Xuhui Central Hospital, Shanghai 200031, P.R. China.
Exp Ther Med. 2018 Feb;15(2):2165-2171. doi: 10.3892/etm.2017.5602. Epub 2017 Dec 6.
The primarily metabolic abnormality in type 2 diabetes mellitus (T2DM) is the defect in gluconeogenesis and glucose uptake. Itraconazole (ITCZ) is a traditional azole drug with anti-fungal and anticancer properties. However, limited attention has been directed towards the contribution of ITCZ to hepatic gluconeogenesis and glucose uptake in T2DM. The present study aimed to investigate the potential effects of ITCZ on hepatic gluconeogenesis and glucose uptake as well as the underlying mechanisms. No obvious change in cell viability was detected by MTT assay in HepG2 cells with ITCZ treatment at gradually increasing concentrations. Western blot analysis demonstrated that the phosphorylation level of 5' adenosine monophosphate-activated protein kinase (AMPK) was significantly elevated by ITCZ treatment at ≥5 µg/ml (P<0.05). Moreover, ITCZ repressed the gluconeogenesis of HepG2 cells, as evidenced by the dose-dependently increased glycogen synthase kinase 3β phosphorylation level and a notably decreased glucose production rate (P<0.05). Simultaneously, the expression of peroxisome proliferator-activated receptor γ co-activator 1α, phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) in HepG2 cells was reduced by ITCZ in a dose-dependent manner (P<0.001). Furthermore, a 2-deoxyglucose uptake assay revealed that the glucose uptake of HepG2 cells was notably enhanced, accompanied by the ITCZ dose-dependent upregulation of glucose transporter-4 (GLUT-4) (P<0.05). Conversely, silencing of AMPK by small interfering RNA resulted in an increase of ITCZ-reduced gluconeogenesis and inhibition of ITCZ-induced glucose uptake with relative upregulation of PEPCK and G6Pase and downregulation of GLUT4 in the presence of 50 µg/ml ITCZ (P<0.05). Overall, the results indicated that AMPK has an important role in regulating ITCZ-induced glucose uptake by stimulating GLUT4 in HepG2 cells. Therefore, ITCZ may become a promising candidate for T2DM therapy.
2型糖尿病（T2DM）主要的代谢异常是糖异生和葡萄糖摄取缺陷。伊曲康唑（ITCZ）是一种具有抗真菌和抗癌特性的传统唑类药物。然而，ITCZ对T2DM患者肝糖异生和葡萄糖摄取的作用却鲜有研究。本研究旨在探讨ITCZ对肝糖异生和葡萄糖摄取的潜在影响及其潜在机制。用逐渐增加浓度的ITCZ处理HepG2细胞，MTT法检测未发现细胞活力有明显变化。蛋白质免疫印迹分析表明，≥5μg/ml的ITCZ处理可显著提高5'单磷酸腺苷激活蛋白激酶（AMPK）的磷酸化水平（P<0.05）。此外，ITCZ抑制了HepG2细胞的糖异生，糖原合酶激酶3β磷酸化水平呈剂量依赖性增加以及葡萄糖生成率显著降低证明了这一点（P<0.05）。同时，ITCZ以剂量依赖性方式降低了HepG2细胞中过氧化物酶体增殖物激活受体γ共激活因子1α、磷酸烯醇式丙酮酸羧激酶（PEPCK）和葡萄糖-6-磷酸酶（G6Pase）的表达（P<0.001）。此外，2-脱氧葡萄糖摄取试验显示，HepG2细胞的葡萄糖摄取显著增强，同时葡萄糖转运蛋白4（GLUT-4）呈ITCZ剂量依赖性上调（P<0.05）。相反，在50μg/ml ITCZ存在的情况下，用小干扰RNA沉默AMPK会导致ITCZ降低的糖异生增加，ITCZ诱导的葡萄糖摄取受到抑制，同时PEPCK和G6Pase相对上调，GLUT4下调（P<0.05）。总体而言，结果表明AMPK在通过刺激HepG2细胞中的GLUT4来调节ITCZ诱导的葡萄糖摄取中起重要作用。因此，ITCZ可能成为治疗T2DM的有前景的候选药物。
