Shenzhen Baoan Shajing People's Hospital of Guangzhou Medical University, Shenzhen, China.
Department of Geriatrics and Cardiovascular Medicine, Shenzhen Sun Yat-Sen Cardiovascular Hospital, Shenzhen, China.
J Cell Physiol. 2019 Apr;234(4):3634-3646. doi: 10.1002/jcp.27133. Epub 2018 Sep 7.
Myocardial ischemia and reperfusion injury (MIRI) includes major drawbacks, such as excessive formation of free radicals and also overload of calcium, which lead to cell death, tissue scarring, and remodeling. The current study aims to explore whether KRT1 silencing may ameliorate MIRI via the Notch signaling pathway in mouse models. Myocardial tissues were used for the determination of the positive rate of KRT1 protein expression, apoptosis of myocardial cells, creatine kinase (CK) and lactate dehydrogenase (LDH) expression, expression of related biomarkers as well as myocardial infarction area. The transfected myocardial cells were treated with KRT1-siRNA, Jagged1, and DAPT (inhibitor of Notch-1 signaling pathway). The expression of KRT1, NICD, Hes1, Bcl-2, and Bax protein was detected. The MTT assay was applied for cell proliferation and flow cytometry was used for cell apoptosis. Mice with MIRI had a higher positive rate of KRT1 protein expression, apoptosis of myocardial cells, CK and LDH expression, myocardial infarction area, increased expression of MDA, NO, SDH, IL-1, IL-6, TNF-α, CRP, KRT1, Bax protein, CK, and LDH, and decreased expression of SOD, NICD, Hes1, and Bcl-2. The downregulation of KRT1 led to decreased expression of KRT1 and Bax protein, increased expression of NICD, Hes1, and Bcl-2, decreased cell apoptosis, and improved cell proliferation. The inhibition of the Notch signaling pathway leads to reduced expression of Bax, increased expression of NICD, Hes1, and Bcl 2, and also decreased cell apoptosis and increased cell proliferation. Our data conclude that KRT1 silencing is able to make MIRI better by activating the Notch signaling pathway in mice.
心肌缺血再灌注损伤（MIRI）包括自由基过度形成和钙超载等主要缺点，导致细胞死亡、组织瘢痕和重塑。本研究旨在探讨 KRT1 沉默是否可以通过 Notch 信号通路改善小鼠模型中的 MIRI。使用心肌组织确定 KRT1 蛋白表达阳性率、心肌细胞凋亡、肌酸激酶（CK）和乳酸脱氢酶（LDH）表达、相关生物标志物表达以及心肌梗死面积。转染的心肌细胞用 KRT1-siRNA、Jagged1 和 DAPT（Notch-1 信号通路抑制剂）处理。检测 KRT1、NICD、Hes1、Bcl-2 和 Bax 蛋白的表达。应用 MTT 法检测细胞增殖，流式细胞术检测细胞凋亡。MIRI 小鼠的 KRT1 蛋白表达阳性率、心肌细胞凋亡、CK 和 LDH 表达、心肌梗死面积均升高，MDA、NO、SDH、IL-1、IL-6、TNF-α、CRP、KRT1、Bax 蛋白、CK 和 LDH 表达增加，SOD、NICD、Hes1 和 Bcl-2 表达减少。下调 KRT1 导致 KRT1 和 Bax 蛋白表达减少，NICD、Hes1 和 Bcl-2 表达增加，细胞凋亡减少，细胞增殖增加。抑制 Notch 信号通路导致 Bax 表达减少，NICD、Hes1 和 Bcl-2 表达增加，细胞凋亡减少，细胞增殖增加。我们的数据表明，KRT1 沉默通过激活小鼠 Notch 信号通路可以改善 MIRI。
