Xiaoming Zhong1, Lei Zhang1, Yanming Li1, Peng Li1, Juan Li1, Guanchang Cheng2. 1. Department of Cardiology, Huaihe Hospital of Henan University, Kaifeng, 475000, China. 2. Department of Cardiology, Huaihe Hospital of Henan University, Kaifeng, 475000, China. Electronic address: m15761010198@163.com.
Abstract
BACKGROUND: Oxidized low-density lipoprotein (ox-LDL) has been well-documented to induce endothelial cell (EC) apoptosis and contribute to the progression of atherosclerosis. Kaempferol was reported to alleviate ox-LDL-induced apoptosis of human umbilical vein endothelial cells. However, the detailed mechanism by which kaempferol alleviated ox-LDL-induced EC apoptosis remains largely elusive. METHODS: The expression of miR-26a-5p in human aortic endothelial cells (HAECs) treated with either ox-LDL alone or in combination with kaempferol was detected by qRT-PCR. Cell viability and apoptosis were assessed by MTT assay and flow cytometry, respectively. The interaction between miR-26a-5p and toll-like receptor 4 (TLR4) mRNA was examined by luciferase reporter assay. The protein levels of TLR4, phosphorylated-p65, p65, phosphorylated-IκBα and IκBα were determined by western blot. RESULTS: Kaempferol upregulated miR-26a-5p expression in ox-LDL-stimulated HAECs. Moreover, kaempferol alleviated ox-LDL-induced apoptosis in HAECs by upregulating miR-26a-5p. Additionally, TLR4 mRNA was identified as a target of miR-26a-5p in ox-LDL-treated HAECs. TLR4 overexpression partially counteracted the anti-apoptotic role of miR-26a-5p in ox-LDL-treated HAECs. Furthermore, kaempferol inactivated the TLR4/nuclear factor kappa B (NF-κB) signaling pathway in ox-LDL-treated HAECs by upregulating miR-26a-5p. CONCLUSION: Kaempferol alleviated ox-LDL-induced apoptosis in HAECs by upregulating miR-26a-5p via inactivation of the TLR4/NF-κB signaling pathway, shedding light on the molecular mechanism by which kaempferol alleviated ox-LDL-induced EC apoptosis.
BACKGROUND: Oxidized low-density lipoprotein (ox-LDL) has been well-documented to induce endothelial cell (EC) apoptosis and contribute to the progression of atherosclerosis. Kaempferol was reported to alleviate ox-LDL-induced apoptosis of human umbilical vein endothelial cells. However, the detailed mechanism by which kaempferol alleviated ox-LDL-induced EC apoptosis remains largely elusive. METHODS: The expression of miR-26a-5p in human aortic endothelial cells (HAECs) treated with either ox-LDL alone or in combination with kaempferol was detected by qRT-PCR. Cell viability and apoptosis were assessed by MTT assay and flow cytometry, respectively. The interaction between miR-26a-5p and toll-like receptor 4 (TLR4) mRNA was examined by luciferase reporter assay. The protein levels of TLR4, phosphorylated-p65, p65, phosphorylated-IκBα and IκBα were determined by western blot. RESULTS:Kaempferol upregulated miR-26a-5p expression in ox-LDL-stimulated HAECs. Moreover, kaempferol alleviated ox-LDL-induced apoptosis in HAECs by upregulating miR-26a-5p. Additionally, TLR4 mRNA was identified as a target of miR-26a-5p in ox-LDL-treated HAECs. TLR4 overexpression partially counteracted the anti-apoptotic role of miR-26a-5p in ox-LDL-treated HAECs. Furthermore, kaempferol inactivated the TLR4/nuclear factor kappa B (NF-κB) signaling pathway in ox-LDL-treated HAECs by upregulating miR-26a-5p. CONCLUSION:Kaempferol alleviated ox-LDL-induced apoptosis in HAECs by upregulating miR-26a-5p via inactivation of the TLR4/NF-κB signaling pathway, shedding light on the molecular mechanism by which kaempferol alleviated ox-LDL-induced EC apoptosis.
Authors: Ariana Centa; Aline S Fonseca; Solange G da Silva Ferreira; Marina Luise V Azevedo; Caroline B Vaz de Paula; Seigo Nagashima; Cleber Machado-Souza; Anna Flavia R Dos Santos Miggiolaro; Cristina P Baena; Lucia de Noronha; Luciane R Cavalli Journal: Am J Physiol Lung Cell Mol Physiol Date: 2020-12-02 Impact factor: 5.464