[Quercetin attenuates Ox-LDL-induced calcification in vascular smooth muscle cells by regulating ROS-TLR4 signaling pathway].

OBJECTIVE To determine whether quercetin inhibits oxidized low-density lipoprotein (Ox-LDL)-induced osteogenic differentiation and calcification of vascular smooth muscle cells (VSMCs) and understand the underlying mechanism. METHODS The calcification of human VSMCs following Ox-LDL treatment was assessed using alizarin red staining and by detecting ALP activity. The mRNA expressions of the bone-related genes including Msx2, BMP2 and Osterix, and the contractile proteins including SMA and SM22a were analyzed using qPCR. The effects of quercetin were investigated on OxLDL-induced VSMC calcification and changes in ALP activity, expressions of Msx2, BMP2, Osterix, SMA and SM22a, ROS levels and SOD activity. The effect of Toll like receptor 4 (TLR4) silencing mediated by siRNA transfection on cell calcification, ALP activity, gene expressions and ROS levels were investigated. RESULTS Ox-LDL treatment promoted VSMC calcification and up-regulated TLR4 expression. Quercetin treatment significantly attenuated Ox-LDL-induced VSMC calcification, reduced ALP activity, down-regulated the expression levels of Msx2, BMP2 and Osterix, and up-regulated the expressions of vascular smooth muscle contractile proteins SMA and SM22a. In addition, Quercetin treatment markedly increased SOD activity, reduced ROS levels and TLR4 expression in VSMCs. Silencing TLR4 expression using TLR4 siRNA also significantly decreased calcification of the VSMCs. CONCLUSIONS Quercetin inhibits Ox-LDL-induced VSMC calcification in VSMCs possibly by targeting the ROS/TLR4 signaling pathway.

[1]  A. Durham,et al.  Role of smooth muscle cells in vascular calcification: implications in atherosclerosis and arterial stiffness , 2018, Cardiovascular research.

[2]  S. Chatterjee,et al.  Quercetin improves endothelial function in diabetic rats through inhibition of endoplasmic reticulum stress‐mediated oxidative stress , 2018, European journal of pharmacology.

[3]  A. Odermatt,et al.  Hydrogen sulfide attenuates calcification of vascular smooth muscle cells via KEAP1/NRF2/NQO1 activation. , 2017, Atherosclerosis.

[4]  A. Nègre-Salvayre,et al.  Dual signaling evoked by oxidized LDLs in vascular cells , 2017, Free radical biology & medicine.

[5]  Sheng-nan Wu,et al.  Ablation of Adenosine Monophosphate-Activated Protein Kinase α1 in Vascular Smooth Muscle Cells Promotes Diet-Induced Atherosclerotic Calcification In Vivo. , 2016, Circulation research.

[6]  Guogang Zhang,et al.  The role of vascular peroxidase 1 in ox-LDL-induced vascular smooth muscle cell calcification. , 2015, Atherosclerosis.

[7]  Fumiaki Sato,et al.  7‐Ketocholesterol‐induced lysosomal dysfunction exacerbates vascular smooth muscle cell calcification via oxidative stress , 2015, Genes to cells : devoted to molecular & cellular mechanisms.

[8]  Lihe Lu,et al.  Ceramide Mediates Ox-LDL-Induced Human Vascular Smooth Muscle Cell Calcification via p38 Mitogen-Activated Protein Kinase Signaling , 2013, PloS one.

[9]  M. Chonchol,et al.  Calcification of the abdominal aorta as an independent predictor of cardiovascular events: a meta-analysis , 2012, Heart.

[10]  K. Fujisaki,et al.  The antioxidant tempol ameliorates arterial medial calcification in uremic rats: Important role of oxidative stress in the pathogenesis of vascular calcification in chronic kidney disease , 2012, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[11]  L. Hofbauer,et al.  Nuclear factor of activated T cells mediates oxidised LDL-induced calcification of vascular smooth muscle cells , 2011, Diabetologia.

[12]  S. Stringer,et al.  Decorin GAG Synthesis and TGF-&bgr; Signaling Mediate Ox-LDL–Induced Mineralization of Human Vascular Smooth Muscle Cells , 2011, Arteriosclerosis, thrombosis, and vascular biology.

[13]  P. Weissberg,et al.  Osteo/Chondrocytic Transcription Factors and Their Target Genes Exhibit Distinct Patterns of Expression in Human Arterial Calcification , 2003, Arteriosclerosis, thrombosis, and vascular biology.

[14]  F. Parhami,et al.  Oxidative stress modulates osteoblastic differentiation of vascular and bone cells. , 2001, Free radical biology & medicine.

[15]  F. Parhami,et al.  Lipid oxidation products have opposite effects on calcifying vascular cell and bone cell differentiation. A possible explanation for the paradox of arterial calcification in osteoporotic patients. , 1997, Arteriosclerosis, thrombosis, and vascular biology.

[16]  A. Pant,et al.  Quercetin decreases steroidogenic enzyme activity, NF-κB expression, and oxidative stress in cultured Leydig cells exposed to atrazine , 2012, Molecular and Cellular Biochemistry.