BACKGROUND: Epoxyeicosatrienoic acids (EETs), which are metabolites of arachidonic acid catalyzed by cytochrome P450 epoxygenase, are degraded into inactive dihydroxyeicosatrienoic acids by soluble epoxide hydrolase (sEH). Many studies have revealed that sEH gene deletion exerts protective effects against diabetes. Vascular calcification is a common complication of diabetes, but the potential effects of sEH on diabetic vascular calcification are still unknown. METHODS: The level of aortic calcification in wild-type and Ephx2-/- C57BL/6 diabetic mice induced with streptozotocin was evaluated by measuring the aortic calcium content through alizarin red staining, immunohistochemistry staining, and immunofluorescence staining. Mouse vascular smooth muscle cell lines (MOVAS cells) treated with β-glycerol phosphate (0.01 mol/L) plus advanced glycation end products (50 mg/L) were used to investigate the effects of sEH inhibitors or sEH knockdown and EETs on the calcification of vascular smooth muscle cells, which was detected by Western blotting, alizarin red staining, and Von Kossa staining. RESULTS: sEH gene deletion significantly inhibited diabetic vascular calcification by increasing levels of EETs in the aortas of mice. EETs (especially 11,12-EET and 14,15-EET) efficiently prevented the osteogenic transdifferentiation of MOVAS cells by decreasing nidogen-2 (NID2) expression. Interestingly, suppressing sEH activity by small interfering ribonucleic acid or specific inhibitors did not block osteogenic transdifferentiation of MOVAS cells induced by β-glycerol phosphate and advanced glycation end products. NID2 overexpression significantly abolished the inhibitory effect of sEH gene deletion on diabetic vascular calcification. Moreover, NID2 overexpression mediated by adeno-associated virus 9 vectors markedly increased insulin-like growth factor 2 (IGF2) and phospho-ERK1/2 expression in MOVAS cells. Overall, sEH gene knockout inhibited diabetic vascular calcification by decreasing aortic NID2 expression and, then, inactivating the downstream IGF2-ERK1/2 signaling pathway. CONCLUSIONS sEH gene deletion markedly inhibited diabetic vascular calcification through repressed osteogenic transdifferentiation of vascular smooth muscle cells mediated by increased aortic EET levels, which was associated with decreased NID2 expression and inactivation of the downstream IGF2-ERK1/2 signaling pathway.
Animals ; Mice ; Vascular Calcification/metabolism* ; Mice, Inbred C57BL ; Epoxide Hydrolases/metabolism* ; Diabetes Mellitus, Experimental/genetics* ; Male ; Gene Deletion ; MAP Kinase Signaling System/genetics* ; Cell Line ; Immunohistochemistry ; Muscle, Smooth, Vascular/metabolism* ; Signal Transduction/genetics* ; Mice, Knockout

OBJECTIVE: To investigate the effects of Bax inhibitor 1 (BI- 1) and optic atrophy protein 1 (OPA1) on vascular calcification (VC). METHODS: Mouse models of VC were established in ApoE-deficient (ApoE^-/-) diabetic mice by high-fat diet feeding for 12 weeks followed by intraperitoneal injections with N^ε-carboxymethyl-lysine for 16 weeks. ApoE^-/- mice (control group), ApoE^-/- diabetic mice (VC group), ApoE^-/- diabetic mice with BI-1 overexpression (VC + BI-1^TG group), and ApoE^-/- diabetic mice with BI-1 overexpression and OPA1 knockout (VC+BI-1^TG+OPA1^-/- group) were obtained for examination of the degree of aortic calcification using von Kossa staining. The changes in calcium content in the aorta were analyzed using ELISA. The expressions of Runt-related transcription factor 2 (RUNX2) and bone morphogenetic protein 2 (BMP-2) were detected using immunohistochemistry, and the expression of cleaved caspase-3 was determined using Western blotting. Cultured mouse aortic smooth muscle cells were treated with 10 mmol/L β-glycerophosphate for 14 days to induce calcification, and the changes in BI-1 and OPA1 protein expressions were examined using Western blotting and cell apoptosis was detected using TUNEL staining. RESULTS: ApoE^-/- mice with VC showed significantly decreased expressions of BI-1 and OPA1 proteins in the aorta (P=0.0044) with obviously increased calcium deposition and expressions of RUNX2, BMP-2 and cleaved caspase-3 (P= 0.0041). Overexpression of BI-1 significantly promoted OPA1 protein expression and reduced calcium deposition and expressions of RUNX2, BMP-2 and cleaved caspase-3 (P=0.0006). OPA1 knockdown significantly increased calcium deposition and expressions of RUNX2, BMP-2 and cleaved caspase-3 in the aorta (P=0.0007). CONCLUSION BI-1 inhibits VC possibly by promoting the expression of OPA1, reducing calcium deposition and inhibiting osteogenic differentiation and apoptosis of the vascular smooth muscle cells.
Animals ; Apolipoproteins E/metabolism* ; Calcium/metabolism* ; Caspase 3/metabolism* ; Cells, Cultured ; Core Binding Factor Alpha 1 Subunit/metabolism* ; Diabetes Mellitus, Experimental/pathology* ; GTP Phosphohydrolases/metabolism* ; Membrane Proteins/metabolism* ; Mice ; Mice, Knockout ; Muscle, Smooth, Vascular/pathology* ; Myocytes, Smooth Muscle/pathology* ; Optic Atrophy, Autosomal Dominant/pathology* ; Osteogenesis ; Vascular Calcification/pathology* ; bcl-2-Associated X Protein/metabolism*

Vascular calcification, the deposition of calcium in the arterial wall, is often linked to increased stiffness of the vascular wall. Vascular calcification is one of the important factors for high morbidity and mortality of cardiovascular and cerebrovascular diseases, as well as an important biomarker in atherosclerotic cardiovascular events, stroke and peripheral vascular diseases. The mechanism of vascular calcification has not been fully elucidated. Recently, non-coding RNAs have been found to play an important role in the process of vascular calcification. In this paper, the main types of non-coding RNAs and their roles involved in vascular smooth muscle cell calcification are reviewed, including the changes of osteoblast-related proteins, calcification signaling pathways and intracellular Ca²⁺.
Humans ; Muscle, Smooth, Vascular/metabolism* ; Vascular Calcification/metabolism* ; Myocytes, Smooth Muscle/metabolism*

Chronic psychological stress can promote vascular diseases, such as hypertension and atherosclerosis. This study aims to explore the effects and mechanism of chronic psychological stress on aortic medial calcification (AMC). Rat arterial calcification model was established by nicotine gavage in combination with vitamin D₃ (VitD₃) intramuscular injection, and rat model of chronic psychological stress was induced by humid environment. Aortic calcification in rats was evaluated by using Alizarin red staining, aortic calcium content detection, and alkaline phosphatase (ALP) activity assay. The expression levels of the related proteins, including vascular smooth muscle cells (VSMCs) contractile phenotype marker SM22α, osteoblast-like phenotype marker RUNX2, and endoplasmic reticulum stress (ERS) markers (GRP78 and CHOP), were determined by Western blot. The results showed that chronic psychological stress alone induced AMC in rats, further aggravated AMC induced by nicotine in combination with VitD₃, promoted the osteoblast-like phenotype transformation of VSMCs and aortic ERS activation, and significantly increased the plasma cortisol levels. The 11β-hydroxylase inhibitor metyrapone effectively reduced chronic psychological stress-induced plasma cortisol levels and ameliorated AMC and aortic ERS in chronic psychological stress model rats. Conversely, the glucocorticoid receptor agonist dexamethasone induced AMC, promoted AMC induced by nicotine combined with VitD₃, and further activated aortic ERS. The above effects of dexamethasone could be inhibited by ERS inhibitor 4-phenylbutyrate. These results suggest that chronic psychological stress can lead to the occurrence and development of AMC by promoting glucocorticoid synthesis, which may provide new strategies and targets for the prevention and control of AMC.
Rats ; Animals ; Glucocorticoids/metabolism* ; Rats, Sprague-Dawley ; Nicotine/metabolism* ; Hydrocortisone/metabolism* ; Muscle, Smooth, Vascular ; Dexamethasone/metabolism* ; Vascular Calcification/metabolism* ; Myocytes, Smooth Muscle/metabolism* ; Cells, Cultured

Vascular calcification is an important pathophysiological basis of cardiovascular disease with its underlying mechanism unclear. In recent years, studies have shown that aging is one of the risk factors for vascular calcification. The purpose of this study was to investigate the microenvironmental characteristics of vascular calcification, identify aging/senescence-induced genes (ASIGs) closely related to calcified plaques, and explore the evolution trajectory of vascular calcification cell subsets. Based on the bioinformatics method, the single cell transcriptome sequencing data (Gene Expression Omnibus: GSE159677) of carotid artery samples from 3 patients undergoing carotid endarterectomy were grouped and annotated. Vascular calcification-related aging genes were identified by ASIGs data set. The pseudotime trend of ASIGs in cell subsets was analyzed by Monocle 3, and the evolution of vascular calcification cells was revealed. After quality control, all cells were divided into 8 cell types, including B cells, T cells, smooth muscle cells, macrophages, endothelial cells, fibroblasts, mast cells, and progenitor cells. Ten ASIGs related to vascular calcification were screened from the data set of ASIGs, which include genes encoding complement C1qA (C1QA), superoxide dismutase 3 (SOD3), lysozyme (LYZ), insulin-like growth factor binding protein-7 (IGFBP7), complement C1qB (C1QB), complement C1qC (C1QC), Caveolin 1 (CAV1), von Willebrand factor (vWF), clusterin (CLU), and αB-crystallin (CRYAB). Pseudotime analysis showed that all cell subsets were involved in the progression of vascular calcification, and these ASIGs may play an important role in cell evolution. In summary, AGIS plays an important role in the progression of vascular calcification, and these high expression genes may provide ideas for early diagnosis and treatment of vascular calcification.
Humans ; Endothelial Cells ; Muscle, Smooth, Vascular ; Aging ; Vascular Calcification/metabolism* ; Computational Biology ; Myocytes, Smooth Muscle/metabolism*

Tanshinone IIa is a key ingredient extracted from the traditional Chinese medicine Salvia miltiorrhiza (Danshen), and is widely used to treat various cardiovascular diseases. Vascular calcification is a common pathological change of cardiovascular tissues in patients with chronic kidney disease, diabetes, hypertension and atherosclerosis. However, whether Tanshinone IIa inhibits vascular calcification and the underlying mechanisms remain largely unknown. This study aims to investigate whether Tanshinone IIa can inhibit vascular calcification using high phosphate-induced vascular smooth muscle cell and aortic ring calcification model, and high dose vitamin D₃ (vD₃)-induced mouse models of vascular calcification. Alizarin red staining and calcium quantitative assay showed that Tanshinone IIa significantly inhibited high phosphate-induced vascular smooth muscle cell and aortic ring calcification. qPCR and Western blot showed that Tanshinone IIa attenuated the osteogenic transition of vascular smooth muscle cells. In addition, Tanshinone IIa also significantly inhibited high dose vD₃-induced mouse aortic calcification and aortic osteogenic transition. Mechanistically, Tanshinone IIa inhibited the activation of NF-κB and β-catenin signaling in normal vascular smooth muscle cells. Similar to Tanshinone IIa, inhibition of NF-κB and β-catenin signaling using the chemical inhibitors SC75741 and LF3 attenuated high phosphate-induced vascular smooth muscle cell calcification. These results suggest that Tanshinone IIa attenuates vascular calcification at least in part through inhibition of NF-κB and β-catenin signaling, and Tanshinone IIa may be a potential drug for the treatment of vascular calcification.
Animals ; Mice ; NF-kappa B/metabolism* ; beta Catenin/metabolism* ; Signal Transduction ; Myocytes, Smooth Muscle/metabolism* ; Vascular Calcification/metabolism* ; Phosphates/metabolism*

OBJECTIVE: To investigate the regulatory role of miRNA-26a in vascular smooth muscle cell (VSMC) calcification by regulating connective tissue growth factor (CTGF). METHODS: Rat thoracic aorta VSMCs (A7r5 cells) with induced calcification were treated with AR234960 agonist or transfected with miR-26a mimic, or with both treatments. Alizarin red staining was used to determine calcium deposition, and phosphatase (ALP) activity in the cells was measured. The mRNA and protein expressions of miR-26a, OPG, OPN, BMP-2 and collagen Ⅱ were detected using qPCR and Western blotting. The binding of miR-26a to CTGF was verified using dual luciferase reporter gene assay. RESULTS: After induced calcification, A7r5 cells showed gradually decreased miR-26a expression (P < 0.05) and progressively increased CTGF expression (P < 0.05) with the extension of induction time. Treatment of the cells with AR234960 obviously increased calcification in the cells, while transfection with miR-26a mimic significantly reduced cell calcification. The calcifying cells showed significantly increased ALP activity and expressions of OPN, BMP-2 and collagen Ⅱ (P < 0.05) and lowered OPG expression (P < 0.05), and treatment with AR234960 did not produce obvious effects on these changes (P > 0.05). Transfection with miR-26a mimic resulted in significantly decreased ALP activity and expressions OPN, BMP-2 and collagen Ⅱ expression (P < 0.05) and increased OPG expression (P < 0.05) in the calcifying cells. These effects of miR-26a mimic was significantly attenuated by treatment of the cells with AR234960 (P < 0.05). The result of luciferase reporter gene assay confirmed the binding of miR-26a to CTGF. CONCLUSION miRNA-26a can effectively alleviate vascular calcification by lowering the level of CTGF, reducing ALP activity and the expressions of OPN, BMP-2 and collagen Ⅱ, and increasing the expression of OPG.
Animals ; Calcium/metabolism* ; Cells, Cultured ; Connective Tissue Growth Factor/pharmacology* ; MicroRNAs/metabolism* ; Muscle, Smooth, Vascular ; Myocytes, Smooth Muscle ; Phosphoric Monoester Hydrolases/pharmacology* ; RNA, Messenger/metabolism* ; Rats ; Sulfones ; Vascular Calcification

This study aims to explore the effects of arachidonic acid lipoxygenase metabolism in vascular calcification. We used 5/6 nephrectomy and high-phosphorus feeding to establish a model of vascular calcification in mice. Six weeks after nephrectomy surgery, vascular calcium content was measured, and Alizarin Red S and Von Kossa staining were applied to detect calcium deposition in aortic arch. Control aortas and calcified aortas were collected for mass spectrometry detection of arachidonic acid metabolites, and active molecules in lipoxygenase pathway were analyzed. Real-time quantitative PCR was used to detect changes in the expression of lipoxygenase in calcified aortas. Lipoxygenase inhibitor was used to clarify the effect of lipoxygenase metabolic pathways on vascular calcification. The results showed that 6 weeks after nephrectomy surgery, the aortic calcium content of the surgery group was significantly higher than that of the sham group (P < 0.05). Alizarin Red S staining and Von Kossa staining showed obvious calcium deposition in aortic arch from surgery group, indicating formation of vascular calcification. Nine arachidonic acid lipoxygenase metabolites were quantitated using liquid chromatography/mass spectrometry (LC-MS) analysis. The content of multiple metabolites (12-HETE, 11-HETE, 15-HETE, etc.) was significantly increased in calcified aortas, and the most abundant and up-regulated metabolite was 12-HETE. Furthermore, we examined the mRNA levels of metabolic enzymes that produce 12-HETE in calcified blood vessels and found the expression of arachidonate lipoxygenase-15 (Alox15) was increased. Blocking Alox15/12-HETE by Alox15 specific inhibitor PD146176 significantly decreased the plasma 12-HETE content, promoted calcium deposition in aortic arch and increased vascular calcium content. These results suggest that the metabolism of arachidonic acid lipoxygenase is activated in calcified aorta, and the Alox15/12-HETE signaling pathway may play a protective role in vascular calcification.
12-Hydroxy-5,8,10,14-eicosatetraenoic Acid ; Animals ; Arachidonate 12-Lipoxygenase ; Arachidonate 15-Lipoxygenase/metabolism* ; Arachidonic Acid ; Hydroxyeicosatetraenoic Acids ; Lipoxygenase/metabolism* ; Mice ; Signal Transduction ; Vascular Calcification

Cardiovascular morbidity and mortality are very common in patients with chronic kidney disease, which may result in part from vascular calcification. Vascular calcification requires osteoblastic trans-differentiation of vascular smooth muscle cells through an active and highly regulated process that is morphologically and functionally similar to bone formation in a number of ways. Multiple studies have been published on this topic, but the precise mechanism of vascular calcification remains unclear. This review presents recent insights into the mechanism of vascular calcification, as well as therapies that modulate mineral metabolism.
Humans ; Metabolism ; Miners ; Mortality ; Muscle, Smooth, Vascular ; Osteoblasts ; Osteogenesis ; Renal Insufficiency, Chronic ; Vascular Calcification

OBJECTIVEVascular calcification is the consequence of the complex interaction between genetic, environmental, and vascular factors, which ultimately lead to the deposition of calcium in the tunica intima (atherosclerotic calcification) or tunica media (Mönckenberg's sclerosis). Vascular calcification is also closely related to other pathologies, such as diabetes mellitus, dyslipidemia, and chronic kidney disease. It has been concluded that the degree of vascular calcification may vary from person to person, even if the associated pathologies and environmental factors are the same. Therefore, this suggests an important genetic contribution to the development of vascular calcification. This review aimed to find the most recent evidence about vascular calcification pathophysiology regarding the genetic aspects and molecular pathways.

DATA SOURCESWe conducted an exhaustive search in Scopus, EBSCO, and PubMed with the keywords "genetics and vascular calcification", "molecular pathways, genetic and vascular calcification" and included the main articles from January 1995 up to August 2016. We focused on the most recent evidence about vascular calcification pathophysiology regarding the genetic aspects and molecular pathways.

STUDY SELECTIONThe most valuable published original and review articles related to our objective were selected.

RESULTSVascular calcification is a multifactorial disease; thus, its pathophysiology cannot be explained by a single specific factor, rather than by the result of the association of several genetic variants, molecular pathway interactions, and environmental factors that promote its development.

CONCLUSIONAlthough several molecular aspects of this mechanism have been elucidated, there is still a need for a better understanding of the factors that predispose to this disease.

Diabetes Mellitus ; metabolism ; physiopathology ; Dyslipidemias ; metabolism ; physiopathology ; Humans ; Kidney Failure, Chronic ; metabolism ; physiopathology ; Renal Insufficiency, Chronic ; metabolism ; physiopathology ; Tunica Intima ; metabolism ; physiopathology ; Tunica Media ; metabolism ; physiopathology ; Vascular Calcification ; metabolism ; physiopathology