Wu Can, Qin Ningning, Ren Huiwen, Yang Min, Liu Shuang, Wang Qiuyue
Department of Endoscope, The First Hospital Affiliated to China Medical University, Shenyang, Liaoning, China.
Department of Endocrinology, The Second People's Hospital of Fuxin City, Fuxin, Liaoning, China.
Int J Endocrinol. 2018 Feb 21;2018:6462793. doi: 10.1155/2018/6462793. eCollection 2018.
Activating AMPK negatively regulates Egr1 to inhibit inflammatory cytokines in high glucose. miR-34a inhibition increases phosphorylated AMPK through mediating SIRT1 to suppress the development of fatty liver.
To clarify the function of Egr1 on the inflammation and fibrosis in high glucose-cultured MCs, as well as to explore the effects of metformin on miR-34a pathway and Egr1 expression.
We transfected MCs with miR-34a inhibitor. And MCs were transfected with small interfering RNA for silencing Egr1 and SIRT1. Quantitative real-time PCR was used to assay the transcription levels of Egr1 mRNA and miR-34a. Western blot was used to test the protein. And ELISA was used to measure inflammatory factors.
High glucose upregulates Egr1 to aggravate the inflammation and fibrosis in MCs. miR-34a suppresses the activation of SIRT1/AMPK and results in promoting Egr1 in high glucose-cultured MCs. Metformin attenuates high glucose-stimulated inflammation and fibrosis in MCs by regulating miR-34a-mediated SIRT1/AMPK activity and the downstream Egr1 protein.
We enriched the effects of miR-34a pathway regulating Egr1 in high glucose-cultured MCs. It provides a foundation for future researches considering Egr1 as a therapeutic target and a new direction for the clinical application of metformin in early DKD.
激活AMPK可负向调节Egr1,以抑制高糖环境下的炎性细胞因子。抑制miR-34a可通过介导SIRT1增加磷酸化AMPK,从而抑制脂肪肝的发展。
阐明Egr1在高糖培养的系膜细胞(MCs)炎症和纤维化中的作用,并探讨二甲双胍对miR-34a通路及Egr1表达的影响。
我们用miR-34a抑制剂转染MCs。并用小干扰RNA转染MCs以沉默Egr1和SIRT1。采用定量实时PCR检测Egr1 mRNA和miR-34a的转录水平。用蛋白质免疫印迹法检测蛋白。并用酶联免疫吸附测定法测量炎性因子。
高糖上调Egr1,加重MCs的炎症和纤维化。在高糖培养的MCs中,miR-34a抑制SIRT1/AMPK的激活,导致Egr1升高。二甲双胍通过调节miR-34a介导的SIRT1/AMPK活性及下游Egr1蛋白,减轻高糖刺激的MCs炎症和纤维化。
我们丰富了miR-34a通路在高糖培养的MCs中调节Egr1的作用。这为未来将Egr1作为治疗靶点的研究提供了基础,也为二甲双胍在早期糖尿病肾病中的临床应用提供了新方向。