BACKGROUND: Medial arterial calcification is a chronic systemic vascular disorder distinct from atherosclerosis and is commonly observed in patients with chronic kidney disease, diabetes, and aging individuals. We previously showed that NR4A3 (nuclear receptor subfamily 4 group A member 3), an orphan nuclear receptor, is a key regulator in apo (apolipoprotein) A-IV-induced atherosclerosis progression; however, its role in vascular calcification is poorly understood. METHODS: We generated NR4A3 ^−/− mice and 2 different types of medial arterial calcification models to investigate the biological roles of NR4A3 in vascular calcification. RNA-seq was performed to determine the transcriptional profile of NR4A3 ^−/− vascular smooth muscle cells under β-glycerophosphate treatment. We integrated Cleavage Under Targets and Tagmentation analysis and RNA-seq data to further investigate the gene regulatory mechanisms of NR4A3 in arterial calcification and target genes regulated by histone lactylation. RESULTS: NR4A3 expression was upregulated in calcified aortic tissues from chronic kidney disease mice, 1,25(OH) ₂ VitD ₃ overload–induced mice, and human calcified aorta. NR4A3 deficiency preserved the vascular smooth muscle cell contractile phenotype, inhibited osteoblast differentiation-related gene expression, and reduced calcium deposition in the vasculature. Further, NR4A3 deficiency lowered the glycolytic rate and lactate production during the calcification process and decreased histone lactylation. Mechanistic studies further showed that NR4A3 enhanced glycolysis activity by directly binding to the promoter regions of the 2 glycolysis genes ALDOA and PFKL and driving their transcriptional initiation. Furthermore, histone lactylation promoted medial calcification both in vivo and in vitro. NR4A3 deficiency inhibited the transcription activation and expression of Phospho1 (phosphatase orphan 1). Consistently, pharmacological inhibition of Phospho1 attenuated calcium deposition in NR4A3-overexpressed vascular smooth muscle cells, whereas overexpression of Phospho1 reversed the anticalcific effect of NR4A3 deficiency in vascular smooth muscle cells. CONCLUSIONS: Taken together, our findings reveal that NR4A3-mediated histone lactylation is a novel metabolome-epigenome signaling cascade mechanism that participates in the pathogenesis of medial arterial calcification.

Rationale:: Macrophages are involved in wound healing after myocardial infarction (MI). The role of Dectin-2, a pattern recognition receptor mainly expressed on myeloid cells, in the infarct healing remains unknown. Objective:: The aim of this study is to determine whether Dectin-2 signaling is involved in the healing process and cardiac remodeling after MI and to elucidate the underlying molecular mechanisms. Methods and Results:: In a mouse model of permanent coronary ligation, Dectin-2, mainly expressed in macrophages, was shown to be increased in the early phase after MI. Dectin-2 knockout mice showed an improvement in the infarct healing and cardiac remodeling, compared with wild-type mice, which was demonstrated by significantly lower mortality because of cardiac rupture, increased wall thickness, and better cardiac function. Increased expression of α-smooth muscle actin and collagen I/III was observed, whereas the levels of matrix metalloproteinase-2 and matrix metalloproteinase-9 were decreased in the hearts of Dectin-2 knockout mice after MI. Dectin-2 deficiency inhibited the rate of apoptotic and necrotic cell death. However, Dectin-2 did not affect immune cell infiltration and macrophage polarization, but it led to a stronger activation of the Th1/interferon-γ immune reaction, through the enhancement of interleukin-12 production in the heart. Interferon-γ was shown to downregulate transforming growth factor-β–induced expression of α-smooth muscle actin and collagen I/III in isolated cardiac fibroblasts, leading to a decrease in migration and myofibroblast differentiation. Finally, Dectin-2 knockout improved myocardial ischemia–reperfusion injury and infarct healing. Conclusions:: Dectin-2 leads to an increase in cardiac rupture, impairs wound healing, and aggravates cardiac remodeling after MI through the modulation of Th1 differentiation.

The extent of coronary collateral formation is a primary determinant of the severity of myocardial damage and mortality after coronary artery occlusion. Type 2 diabetes mellitus (T2DM) represents an important risk factor for impaired collateral vessel growth. However, the mechanism of reduced coronary collateralization in type 2 diabetic patients remains unclear. With the reference to the recent researches, this review article describes the pathogenic effects of T2DM on collateral development and outlines possible clinical and biochemical markers associated with reduced coronary collateralization in type 2 diabetic patients with chronic total occlusion (CTO). Diffuse coronary atherosclerosis in T2DM reduces pressure gradient between collateral donor artery and collateral recipient one, limiting collateral vessel growth and function. An interaction between advanced glycation end-products and their receptor activates several intracellular signaling pathways, enhances oxidative stress and aggravates inflammatory process. Diabetic condition decreases pro-angiogenic factors especially vascular endothelial growth factor and other collateral vessel growth related parameters. Numerous clinical and biochemical factors that could possibly attenuate the development of coronary collaterals have been reported. Increased serum levels of glycated albumin, cystatin C, and adipokine C1q tumor necrosis factor related protein 1 were associated with poor coronary collateralization in type 2 diabetic patients with stable coronary artery disease and CTO. Diastolic blood pressure and stenosis severity of the predominant collateral donor artery also play a role in coronary collateral formation. T2DM impairs collateral vessel growth through multiple mechanisms involving arteriogenesis and angiogenesis, and coronary collateral formation in patients with T2DM and CTO is influenced by various clinical, biochemical and angiographic factors. This information provides insights into the understanding of coronary pathophysiology and searching for potential new therapeutic targets in T2DM.

Background: The aim of the present cross-sectional study was to assess possible associations between osteopontin (OPN), and thrombin-cleaved (N-half) OPN, and nephropathy and coronary artery disease (CAD) in patients with type 2 diabetes mellitus (T2DM). Methods: Plasma levels of OPN, N-half OPN, and high-sensitivity C-reactive protein (hsCRP) were determined in 301 diabetic patients with (n = 226) or without (n = 75) angiographically documented CAD (luminal diameter narrowing >50%), as well as in 75 non-diabetic controls with normal angiography. The estimated glomerular filtration rate (eGFR) was calculated in all patients. Results: Plasma levels of OPN and hsCRP were significantly higher in patients with T2DM compared with controls. In addition, there was a higher occurrence of moderate renal insufficiency and lower eGFR in patients with T2DM (all P < 0.01). T2DM patients in whom OPN levels were greater than the median value had higher serum creatinine levels, a greater prevalence of mild or moderate renal insufficiency, a higher incidence of CAD, and lower eGFR (all P < 0.05) than T2DM patients in whom OPN levels were the same as or lower than the median value. However, there were no differences in these parameters when patients were stratified according to plasma N-half OPN levels. Furthermore, there was a significant correlation between OPN, but not N-half OPN, and the severity of nephropathy and CAD in diabetes. After adjustment for potential confounders and treatments, multiple linear regression analysis demonstrated an independent association between OPN, but not N-half OPN, and eGFR. Multivariate logistic regression revealed that higher OPN levels conferred a fourfold greater risk of renal insufficiency and CAD in patients with T2DM. Conclusions: The results of the present study demonstrate that there is an independent association between plasma levels of OPN, but not N-half OPN, and the presence and severity of nephropathy and CAD in diabetes.

Background: The aim of our study was to explore and evaluate the relationship between insulin resistance and progression of coronary atherosclerotic plaques. With the great burden coronary heart disease is imposing on individuals, healthcare professionals have already embarked on determining its potential modifiable risk factors in the light of preventive medicine. Insulin resistance has been generally recognized as a novel risk factor based on epidemiological studies; however, few researches have focused on its effect on coronary atherosclerotic plaque progression. Methods: From June 7, 2007 to December 30, 2011, 366 patients received their index coronary angiogram and were subsequently found to have coronary atherosclerotic plaques or normal angiograms were consecutively enrolled in the study by the department of cardiology at the Ruijin Hospital, which is affiliated to the Shanghai Jiaotong University School of Medicine. All patients had follow-up angiograms after the 1-year period for evaluating the progression of the coronary lesions. The modified Gensini score was adopted for assessing coronary lesions while the HOMA-IR method was utilized for determining the state of their insulin resistance. Baseline characteristics and laboratory test results were described and the binomial regression analysis was conducted to investigate the relationship between insulin resistance and coronary atherosclerotic plaque progression. Results: Index and follow-up Gensini scores were similar between the higher insulin lower insulin resistant groups (9.09 ± 14.33 vs 9.44 ± 12.88, p = 0.813 and 17.21 ± 18.46 vs 14.09 ± 14.18, p =0.358). However the Gensini score assessing coronary lesion progression between both visits was significantly elevated in the higher insulin resistant group (8.13 ± 11.83 versus 4.65 ± 7.58, p = 0.019). Multivariate logistic binomial regression analysis revealed that insulin resistance (HOMA-IR > 3.4583) was an independent predictor for coronary arterial plaque progression (OR = 4.969, p = 0.011). We also divided all the participants into a diabetic (n = 136) and a non-diabetic group (n = 230), and HOMA-IR remained an independent predictor for atherosclerosis plaque progression. Conclusions: Insulin resistance is an independent predictor of atherosclerosis plaque progression in patients with coronary heart disease in both the diabetic and non-diabetic population.