Xinran Li1, Hesheng Hu2, Ye Wang2, Mei Xue2, Xiaolu Li2, Wenjuan Cheng2, Yongli Xuan1, Jie Yin1, Na Yang1, Suhua Yan3. 1. School of Medicine, Shandong University, Ji'nan, Shandong, China. 2. Department of Cardiology, Qianfoshan Hospital of Shandong Province, Ji'nan, Shandong, China. 3. Department of Cardiology, Qianfoshan Hospital of Shandong Province, Ji'nan, Shandong, China. Electronic address: yansuhua296@163.com.
Abstract
BACKGROUND: MicroRNAs have an important role in regulating arrhythmogenesis. MicroRNA-16 (miR-16) is predicted to target KCNJ2. The regulation of miR-16 is primarily due to NF-κB. Whether valsartan could downregulate miR-16 via the inhibition of NF-κB after MI and whether miR-16 targets KCNJ2 remain unclear. METHODS: MI rats received valsartan or saline for 7days. The protein levels of NF-κB p65, inhibitor κBα (IκBα), and Kir2.1 were detected by Western blot analysis. The mRNA levels of Kir2.1 and miR-16 were examined by quantitative real-time PCR. Whole cell patch-clamp techniques were applied to record IK1. RESULTS: MiR-16 expression was higher in the infarct border, and was accompanied by a depressed IK1/KIR2.1 level. Additionally, miR-16 overexpression suppressed KCNJ2/KIR2.1 expression. In contrast, miR-16 inhibition or binding-site mutation enhanced KCNJ2/KIR2.1 expression, establishing KCNJ2 as a miR-16 target. In the MI rats, compared to saline treatment, valsartan reduced NF-κB p65 and miR-16 expression and increased IκBα and Kir2.1 expression. In vitro, angiotensin II increased miR-16 expression and valsartan inhibited it. Overexpressing miR-16 in cells treated with valsartan abrogated its beneficial effect on KCNJ2/Kir2.1. NF-κB activation directly upregulates miR-16 expression. CONCLUSIONS: miR-16 controls KCNJ2 expression, and valsartan ameliorates Kir2.1 after MI partly depending on the NF-κB-miR-16 pathway.
BACKGROUND: MicroRNAs have an important role in regulating arrhythmogenesis. MicroRNA-16 (miR-16) is predicted to target KCNJ2. The regulation of miR-16 is primarily due to NF-κB. Whether valsartan could downregulate miR-16 via the inhibition of NF-κB after MI and whether miR-16 targets KCNJ2 remain unclear. METHODS:MIrats received valsartan or saline for 7days. The protein levels of NF-κB p65, inhibitor κBα (IκBα), and Kir2.1 were detected by Western blot analysis. The mRNA levels of Kir2.1 and miR-16 were examined by quantitative real-time PCR. Whole cell patch-clamp techniques were applied to record IK1. RESULTS:MiR-16 expression was higher in the infarct border, and was accompanied by a depressed IK1/KIR2.1 level. Additionally, miR-16 overexpression suppressed KCNJ2/KIR2.1 expression. In contrast, miR-16 inhibition or binding-site mutation enhanced KCNJ2/KIR2.1 expression, establishing KCNJ2 as a miR-16 target. In the MIrats, compared to saline treatment, valsartan reduced NF-κB p65 and miR-16 expression and increased IκBα and Kir2.1 expression. In vitro, angiotensin II increased miR-16 expression and valsartan inhibited it. Overexpressing miR-16 in cells treated with valsartan abrogated its beneficial effect on KCNJ2/Kir2.1. NF-κB activation directly upregulates miR-16 expression. CONCLUSIONS:miR-16 controls KCNJ2 expression, and valsartan ameliorates Kir2.1 after MI partly depending on the NF-κB-miR-16 pathway.
Authors: Jie Yin; Shuling You; Nannan Li; Shouhai Jiao; Hesheng Hu; Mei Xue; Ye Wang; Wenjuan Cheng; Ju Liu; Min Xu; Suhua Yan; Xiaolu Li Journal: Respir Res Date: 2016-08-04
Authors: Laura van der Schoor; Emma J van Hattum; Sophie M de Wilde; Netanja I Harlianto; Aart-Jan van Weert; Meye Bloothooft; Marcel A G van der Heyden Journal: Int J Mol Sci Date: 2020-08-11 Impact factor: 5.923