背景:具有反向结构域结构1(MAGI1)的膜相关鸟苷酸激酶在糖尿病中失调;然而,其在糖尿病肾病(DN)中的作用尚不清楚。在这项研究中,我们确定了MAGI1在DN中的功能和相关机制。
方法:收集28例DN患者和28名正常志愿者的血清样本。高糖(HG)处理的人肾系膜细胞(HRMC)和链脲佐菌素处理的大鼠被用作DN的细胞和动物模型,分别。通过定量逆转录聚合酶链反应测量MAGI1mRNA表达。5-乙炔基-2'-脱氧尿苷测定法用于评估细胞增殖,而蛋白质印迹分析是为了定量与增殖相关的标志物水平,细胞外基质(ECM),和炎症。这些包括胶原蛋白I,胶原蛋白IV,细胞周期蛋白D1,AKT,磷酸化AKT(p-AKT),PI3K,和磷酸化-PI3K(p-PI3K)。使用荧光素酶测定法验证miR-205-5p与MAGI13'UTR的预测结合。
结果:在DN患者的血清样本和用HG治疗的HRMC中,MAGI1表达增加。MAGI1敲低减弱过度增殖,ECM积累,HG诱导的HRMC的炎症反应以及对DN大鼠的损伤。MiR-205-5p可能与MAGI1的3'UTR相互作用,并使用双荧光素酶报告基因测定法验证了结合。此外,miR-205-5p抑制抵消了MAGI1敲低对增殖的抑制作用,胶原蛋白沉积,和HG治疗的HRMC中的炎症。
结论:MAGI1有助于DN引起的损伤。此外,miR-205-5p结合MAGI1并抑制MAGI1功能。这些结果表明,miR-205-5p介导MAGI1抑制,这代表了DN的潜在治疗方法。
BACKGROUND: Membrane-associated guanylate kinase with an inverted domain structure-1 (MAGI1) is dysregulated in diabetes; however, its role in diabetic nephropathy (DN) remains unclear. In this study, we determined the function and associated mechanisms of MAGI1 in DN.
METHODS: Serum samples from 28 patients with DN and 28 normal volunteers were collected. High-glucose (HG)-treated human renal mesangial cells (HRMCs) and streptozotocin-treated rats were used as cell and animal models of DN, respectively. MAGI1 mRNA expression was measured by quantitative reverse transcription polymerase chain reaction. An 5-Ethynyl-2\'-deoxyuridine assay was used to assess cell proliferation, whereas Western blot analysis was performed to quantitate the levels of markers associated with proliferation, the extracellular matrix (ECM), and inflammation. These included collagens I, collagen IV, cyclin D1, AKT, phosphorylated-AKT (p-AKT), PI3K, and phosphorylated-PI3K (p-PI3K). The predicted binding of miR-205-5p with the MAGI1 3\'UTR was verified using a luciferase assay.
RESULTS: MAGI1 expression was increased in serum samples from DN patients and in HRMCs treated with HG. MAGI1 knockdown attenuated excessive proliferation, ECM accumulation, and inflammation in HG-induced HRMCs as well as injury to DN rats. MiR-205-5p potentially interacted with the 3\'UTR of MAGI1 and binding was verified using a dual-luciferase reporter assay. Moreover, miR-205-5p repression offset the inhibitory influence of MAGI1 knockdown on proliferation, collagen deposition, and inflammation in HG-treated HRMCs.
CONCLUSIONS: MAGI1 contributes to injury caused by DN. Furthermore, miR-205-5p binds to MAGI1 and suppresses MAGI1 function. These findings suggest that miR-205-5p-mediates MAGI1 inhibition, which represents a potential treatment for DN.