Ru-Qiong Nie

CRP regulates the expression and activity of tissue factor as well as tissue factor pathway inhibitor via NF‐κB and ERK 1/2 MAPK pathway

It was found that C‐reactive protein (CRP) could significantly increase the expression and activity of tissue factor (TF), but decrease that of tissue factor pathway inhibitor (TFPI) in human umbilical vein endothelial cells (HUVECs) in dose‐ and time‐dependent manners, which could be antagonized by PDTC and U0126. CRP could also increase protein expression of phosphorylated nuclear factor‐kappaB (NF‐κB), IκB‐α and ERK1/2 in dose‐ and time‐dependent manner. In addition, neutralizing antibody to CD32 (FcgammaR II) could significantly attenuate the expression and activity of TF and TFPI induced by CRP. These results suggest that CRP may promote coagulation by enhancing the expression and activity of TF and reducing that of TFPI by activating NF‐κB and extracellular signal‐regulated kinase via FcgammaR II.

Differentiated markers in undifferentiated cells: Expression of smooth muscle contractile proteins in multipotent bone marrow mesenchymal stem cells

In studying the differentiation of stem cells along smooth muscle lineage, smooth muscle cell (SMC) contractile proteins serve as markers for the relative state of maturation. Yet, recent evidence suggests that some SMC markers are probably expressed in multipotent mesenchymal stem cells (MSCs). Such a paradox necessitates investigations to re‐examine their role as differentiated markers in MSCs. We tried to detect the expression of four widely used SMC markers including α‐smooth muscle actin (α‐SMA), h1‐calponin, desmin and smooth muscle myosin heavy chain (SM‐MHC), as well as the other isoforms of calponin family in resting MSCs. Then we used three different conditions to initiate MSCs differentiation along SMC lineage, and examined the alternation of SMC markers expression at both the transcript level and protein level. Desmin and h1‐calponin are expressed in MSCs, in the presence or absence of SMC induction conditions. Moreover, MSCs are shown to express all known isoforms of calponin. Double‐staining reveals that h1‐calponin +/α‐SMA – cells constitute the majority of resting MSCs. Under differentiated conditions, expression of SM‐MHC was initiated and expression of α‐SMA was promoted. The expression of SM‐MHC and upregulation of α‐SMA are relatively reliable indications of a mature smooth muscle phenotype in MSCs. Given that the cells are particularly rich in calponins expression, we postulate possible roles of these proteins in regulating cellular function by taking part in actin cytoskeleton and signaling. These findings imply that an extensive study of the cell physiology of MSCs should focus on the functional roles for these proteins, rather than simply regard them as differentiated markers.

Inhibition of Protein Kinase C β2 Prevents Tumor Necrosis Factor-α-Induced Apoptosis and Oxidative Stress in Endothelial Cells: The Role of NADPH Oxidase Subunits

We investigate the cell signal transduction pathway protein kinase C (PKC) and the role of NADPH subunits in the process of TNF-α-induced endothelial apoptosis. Human umbilical vein endothelial cells (HUVEC) were treated with one of these: 1 mM PKC β2 inhibitor CGP53353, 10 mM PKC δ inhibitor rottlerin, combination CGP53353 with rottlerin, 3 ×10–4M NADPH oxidase inhibitor apocynin, 5 × 10–6M NADPH oxidase peptide inhibitor gp91ds-tat. The apoptosis process was assessed by Hoechst 33342 stain, flow cytometry and Western blot analysis, while intracellular reactive oxygen species (ROS) production was detected by 2,7’-dichlorodihydrofluorescein diacetate (DCFH-DA). The NADPH oxidase subunit gene and protein expression were assessed by quantitative real-time PCR and Western blot analysis, respectively. TNF-α significantly induced HUVEC apoptosis and ROS production, accompanying with dramatic upregulation of NADPH oxidase subunits: NOX2/gp91phox, NOX4, p47phox and p67phox, whereas these enhancements were abolished by the treatment with PKC inhibitors. High TNF-α level exposure induces HUVEC apoptosis, as well as a ROS generation increase via the PKC β2-dependent activation of NADPH oxidase. Although the PKC δ pathway may enhance TNF-α-induced HUVEC apoptosis, it does not involve the ROS pathway. Upregulation of expression of NADPH subunits is important in this process, which leads to a new target in antioxidative therapy for vascular disease prevention.

C-reactive protein promotes vascular endothelial dysfunction partly via activating adipose tissue inflammation in hyperlipidemic rabbits

BACKGROUND Endothelial dysfunction is the basic and original sign of atherogenesis. Some evidences show that C-reactive protein (CRP) and perivascular adipose tissue (PVAT) play a pivotal role in atherosclerosis. However, the effects of CRP on atherosclerosis and the related mechanisms require elucidation. METHODS The levels of basic total cholesterol, low-density lipoprotein cholesterol, triglyceride, CRP, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nitric oxide (NO) and endothelin-1 (ET-1) were respectively measured in rabbits, endothelium-dependent vasorelaxation function was also evaluated. Animals were randomly divided into two groups: PVAT(-) and PVAT(+) group (removing or keeping pericarotid adipose tissue (PCAT)). Both of the two groups were exposed to a high-fat diet for six-week, and then sustained CRP treatment was performed for a week, at this time point all the above parameters were remeasured. In addition, mRNA and protein expression of TNF-α, IL-6, and macrophage chemoattractant protein-1 (MCP-1) were respectively evaluated by Polymerase Chain Reaction and immunoblotting in PCAT and cultured adipocytes treated by CRP. RESULTS High-fat diet greatly increased the serum lipids and inflammatory markers, induced endothelial dysfunction and imbalance between NO and ET-1, increased mRNA and protein expression of TNF-α, IL-6, MCP-1 and enhanced macrophage infiltration of PCAT. CRP treatment could further promote macrophage infiltration of PVAT, induce the imbalance between NO and ET-1, aggravate endothelial dysfunction especially in PVAT(+) arteries, and could also enhance the above-mentioned mRNA and protein expression in PCAT and cultured adipocytes. CONCLUSIONS CRP could significantly promote endothelial dysfunction in high-fat diet rabbits especially in PVAT(+) groups, which may be partly mediated by activating inflammatory reaction of adipose tissue.

Optimal strategy of coronary revascularization in chronic kidney disease patients: a meta-analysis.

BACKGROUND Patients with chronic kidney disease (CKD) have high risks of coronary artery disease (CAD). Coronary revascularization is beneficial for long-term survival, but the optimal strategy remains still controversial. METHODS We searched studies that have compared percutaneous coronary intervention (PCI) and coronary artery bypass graft (CABG) for revascularization of the coronary arteries in CKD patients. Short-term (30 days or in-hospital) mortality, long-term (at least 12 months) all-cause mortality, cardiac mortality and the incidence of late myocardial infarction and recurrence of revascularization were estimated. RESULTS 28 studies with 38,740 patients were included. All were retrospective studies from 1977 to 2012. Meta-analysis showed that PCI group had lower short-term mortality (OR 0.55, 95% CI 0.41 to 0.73, P<0.01), but had higher long-term all-cause mortality (OR 1.29, 95% CI 1.23 to 1.35, P<0.01). Higher cardiac mortality (OR 1.08, 95% CI 1.01 to 1.15, P<0.05), higher incidence of late myocardial infarction (OR 1.78, 95% CI 1.65 to 1.91, P<0.01) and recurring revascularization rate (OR 2.94, 95%CI 2.15 to 4.01, P<0.01) is found amongst PCI treated patients compared to CABG group. CONCLUSIONS CKD patients with CAD received CABG had higher risk of short-term mortality but lower risks of long-term all-cause mortality, cardiac mortality and late myocardial infarction compared to PCI. This could be due to less probable repeated revascularization.

Endogenous pro-resolving and anti-inflammatory lipid mediators: The new hope of atherosclerotic diseases

Atherosclerosis is a complex disease process in which genetic, lipid, cellular, and immunological factors combine to determine the location, severity, and timing of lesion development and clinical events. It has been demonstrated, however, that inflammation governed atherosclerosis during the course of development of atherosclerosis. It has also been demonstrated to be effective to decrease the cardiovascular events and improve the prognosis of atherosclerotic diseases by regulating inflammatory reaction (e.g., statins). However, endogenous mechanisms of limiting inflammation in atherosclerosis are still unclear. Recent studies showed that lipoxidase/leukotrienes (LOX/LTs) pathway played important role in the ignition and development of atherosclerosis, whereas resolvins (E-series resolvins and D-series resolvins) and protectins [protectin D1 (PD1) and neuroprotectin D1 (NPD1)], endogenous lipid-derived mediators, inhibited inflammation through pro-resolution and counter-modulating immune inflammation reaction in atherosclerosis. Hence, we hypothesize that increased endogenous lipid mediators mentioned above play a vital role in anti-atherosclerosis and plaque stabilization through pro-resolution and anti-inflammation by LOX/LTs pathway. In addition, we predict that the endogenous lipid mediators may be a new target for treatment of atherosclerotic diseases.

Role of Circulating Fibrocytes in Cardiac Fibrosis

Objective:It is revealed that circulating fibrocytes are elevated in patients/animals with cardiac fibrosis, and this review aims to provide an introduction to circulating fibrocytes and their role in cardiac fibrosis. Data Sources:This review is based on the data from 1994 to present obtained from PubMed. The search terms were “circulating fibrocytes” and “cardiac fibrosis”. Study Selection:Articles and critical reviews, which are related to circulating fibrocytes and cardiac fibrosis, were selected. Results:Circulating fibrocytes, which are derived from hematopoietic stem cells, represent a subset of peripheral blood mononuclear cells exhibiting mixed morphological and molecular characteristics of hematopoietic and mesenchymal cells (CD34+/CD45+/collagen I+). They can produce extracellular matrix and many cytokines. It is shown that circulating fibrocytes participate in many fibrotic diseases, including cardiac fibrosis. Evidence accumulated in recent years shows that aging individuals and patients with hypertension, heart failure, coronary heart disease, and atrial fibrillation have more circulating fibrocytes in peripheral blood and/or heart tissue, and this elevation of circulating fibrocytes is correlated with the degree of fibrosis in the hearts. Conclusions:Circulating fibrocytes are effector cells in cardiac fibrosis.

Oxidized Low-Density Lipoprotein-Induced Cyclophilin A Secretion Requires ROCK-Dependent Diphosphorylation of Myosin Light Chain.

Objective: Accumulation of cyclophilin A (CyPA) within atherosclerotic lesions is thought to be implicated in the progression of atherosclerosis. However, the source of CyPA within atherosclerotic lesions is still unknown. The aim of this study is to determine the role of oxidized low-density lipoproteins (ox-LDL) in vascular smooth muscle cell (VSMC)-derived CyPA secretion and the underlying mechanism. Methods and Results: Abundant CyPA and α-smooth muscle actin (α-SMA) expressed in atherosclerotic lesions was observed in apolipoprotein E-deficient mice. ox-LDL induced CyPA secretion from a primary culture of rat aortic smooth muscle cells in a dose- and time-dependent manner. Sulfosuccinimidyloleate, a CD36 inhibitor, prevented the ox-LDL-induced CyPA secretion. Pre-exposure to either the actin-depolymerizing agent cytochalasin D or the actin-polymerizing agent jasplakinolide inhibited CyPA secretion induced by ox-LDL. Gene silencing of vesicle-associated membrane protein 2 suppressed ox-LDL-induced CyPA secretion. ox-LDL caused the phosphorylation of myosin light chain (MLC). Inhibition of MLC by blebbistatin reversed the secretion of CyPA and the phosphorylation of MLC induced by ox-LDL. MLC kinase inhibitor ML-7 reduced the monophosphorylation of MLC but did not reduce CyPA secretion. Pretreatment with the rho-associated coiled-coil kinase (ROCK) inhibitor Y27632 blocked diphosphorylation of MLC and secretion of CyPA induced by ox-LDL. Conclusions: ox-LDL-induced CyPA secretion requires vesicle transportation, actin remodeling and ROCK-dependent diphosphorylation of MLC. VSMC-derived CyPA induced by ox-LDL may be associated with increased CyPA expression in atherosclerotic lesions.

Retrospective analysis of risk factors in young patients with coronary artery disease in Guangdong and Zhejiang, China.

Objectives — The objective of this study is to investigate the clustering status of risk factors for young patients with coronary artery disease (CAD) and analyse the relationship between risk factors and CAD. Methods — 168 patients with CAD aged under 45 years, 170 age-matched non-CAD individuals (angiographically normal) and 170 patients with CAD aged over 45 years were set as CAD group, control group and reference group, respectively. Plasma levels of lipids, C-reactive protein (CRP), traditional risk factors (hypertension, hyperlipidaemia, diabetes, obesity, smoking) were evaluated. Results — The following results were obtainted: (1) there was a significant difference in gender, proportion of smoking, TC and TG between the CAD group and the control group, and also in gender, smoking, hypertension, diabetes, BMI and blood lipids between the CAD group and the reference group (P < 0.05); (2) there was a significant difference in levels of TG, TC, HDL-C, LDL-C and BMI (P < 0.05), but no remarkable difference in ApoB/ApoA1 and CRP between the CAD group and the reference group (P > 0.05).There were significant differences in TG, ApoB/ApoA1 and CRP (P < 0.05), but no remarkable difference in other factors between the CAD group and the control group (P > 0.05); (3) logistic regression showed a close relationship between CAD and smoking (OR = 2.5, 95% CI: 1.43~3.98), CRP (OR = 2.71, 95% CI: 1.46~5.88), TG (OR = 1.58, 95%CI: 1.25~2.75) and ApoB/ApoA1 (OR = 1.93, 95% CI: 1.14~3.13). Conclusions — Smoking, CRP, ApoB/ApoA1 ratio and TG are independent risk factors for young patients with CAD.

Bare-metal stent versus drug-eluting stent in large coronary arteries: meta-analysis of randomized controlled trials.

Uncertainties exist with regard to the efficacy of drug‐eluting stent (DES) versus bare‐metal stent (BMS) in large coronary arteries.