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Background: Atherosclerosis is an inflammatory disease involving activation of adaptive and innate immune responses to antigens, including oxidized low-density lipoprotein (oxLDL) and phosphorylcholine (PC). Dendritic cells (DCs), which are antigen-presenting cells that activate T cells, are present in atherosclerotic lesions and are activated in immune organs. However, the mechanism by which PC promotes atherosclerosis is unclear. Methods and Results: To evaluate whether PC promotes atherosclerosis via DCs, 2×105 DCs activated by PC-keyhole limpet hemocyanin (DCs+PC-KLH) were injected into ApoE−/− mice and the features of the plaques and the effects of the DCs on cellular and humoral immunity against PC-KLH were determined. Mice injected with DCs+PC-KLH had significantly larger atherosclerotic lesions than controls, with increased inflammation in the lesions and plaque instability. Furthermore, DCs+PC-KLH were characterized using flow cytometry after coculture of bone marrow-derived DCs and naïve T cells. DCs+PC-KLH showed an inflammatory phenotype, with increased CD86, CD40, and major histocompatibility complex Class II molecules (MHC-II), which promoted PC-specific T helper (Th) 1 and Th17 cell differentiation in vivo and in vitro. Moreover, 2 weeks after the administration of DCs+PC-KLH to mice, these mice produced PC- and oxLDL-specific IgG2a, compared with no production in the controls. Conclusions: These findings suggest that DCs presenting PC promote specific immunity to PC, increase lesion inflammation, and accelerate atherosclerosis, which may explain how PC promotes atherosclerosis.

Many studies have suggested that VSMC (vascular smooth muscle cell) apoptosis plays a key role in destabilization and rupture of atherosclerotic plaques. Therefore protection for VSMCs from apoptosis is a promising approach to stabilize 'vulnerable' lesions. However, the mechanisms as to why VSMCs in the fibrous cap often appear as profilerated in early stages, but turn apoptotic in advanced stages, are still unknown. In the present study, using RNAi (RNA interference) technology and a CaN (calcineurin) antagonist, the correlation between CaN and RANTES (regulated upon activation, normal T-cell expressed and secreted) in cultured rat apoptotic VSMCs stimulated by IFNgamma (interferon gamma; 20 ng/ml) and CD40L (CD40 ligand; 100 ng/ml) was investigated. RANTES released from VSMCs in each group was measured by ELISA and its mRNA in VSMCs was determined by RT (reverse transcription)-PCR. The total activity and expression of CaN in VSMCs were detected by the zymochemistry method and Western blot analysis respectively. From the results of the present study it can be hypothesized that an elevated CaN concentration in endochylema, by the CD40-CD40L signal pathway, induces VSMC apoptosis accomplished by the overexpression of RANTES. Therefore RANTES is a potential target for treating vulnerable atherosclerotic plaques owing to its crucial downstream regulating role in CaN-dependent VSMC apoptosis.

Background Ketanserin (KT), a selective serotonin (5-HT) 2-receptor antagonist, reduces peripheral blood pressure by blocking the activation of peripheral 5-HT receptors. In this study electrophysiological method was used to investigate the effect of KT and potassium ion on Kv1.3 potassium channels and explore the role of blocker KT in the alteration of channel kinetics contributing to the potassium ion imbalances. Methods Kv1.3 channels were expressed in xenopus oocytes, and currents were measured using the two-microelectrode voltage-clamp technique. Results KCI made a left shift of activation and an inactivation curve of Kv1.3 current and accelerated the activation and inactivation time constant. High extracellular [K + ] attenuated the blockade effect of KT on Kv1.3 channels. In the presence of KT and KCI the activation and inactivation time constants were not influenced significantly no matter what was administered first. KT did not significantly inhibit Kv1.3 current induced by tetraethylammonium (TEA). Conclusions KT is a weak blocker of Kv1.3 channels at different concentrations of extracellular potassium and binds to the intracellular side of the channel pore. The inhibitor KT of ion channels is not fully effective in clinical use because of high [K + ] o and other electrolyte disorders.

Angiographically visible complex lesions, associated with disrupted plaques and intraluminal thrombus, are more common in unstable angina (UA). The aim of our study was to evaluate the relationship between the complex lesions and the T helper cells related Interleukins (IL). We analyzed the concentrations of IL-10, IL-12, IL-18 using ELISA and that of hsCRP using Latex particle enhanced Immunoturbidimetry in 50 patients of UA. Thirty-one of these patients had complex lesions and 19 had simple lesions as visible during coronary angiography. We further compared them with 30 control subjects having no evidence of coronary artery diseases. The levels of IL-12 in patients having complex lesions tended to be higher than in those having simple lesions and levels of IL-10 tended to be lower in the former than the latter, but the differences were not statistically significant. The patients with complex lesions showed significantly higher concentrations of IL-18 as compared to those having simple lesions. Furthermore, IL-18 was found to be independent predictor for the complex lesion morphology in UA patients. These findings suggest that disrupted plaques and intraluminal thrombus, angiographically visible as complex lesions are associated with increased concentrations of T helper 1 cell related interleukins, mainly IL-18, and IL-18 being a possible bio-marker for risk stratification in UA.

Atherosclerosis is an inflammatory disease characterized by extensive lipid deposition and atherosclerotic plaque formation in the intima. Interleukin (IL)-37 is anti-inflammatory cytokine in the IL-1 ligand family. Given that IL-37 plays an important function in the development and progression of inflammatory and autoimmune diseases, it may be associated with the development of atherosclerosis. IL-37, which is normally expressed at low levels in peripheral blood mononuclear cells (PBMC), mainly monocytes, and dendritic cells (DC), is rapidly up-regulated in the inflammatory context, and therefore IL-37 conversely inhibits the production of inflammatory cytokines in PBMC and DC. In addition, IL-37 effectively suppresses the activation of macrophage and DC. It is not controversial that the activation of macrophage and DC and the over-expression of inflammatory cytokines are critical component elements in inflammatory process of atherosclerosis. Therefore, IL-37 may play a protective role in atherosclerosis through inhibition of inflammatory cytokines production and suppression of macrophage and DC activation.

To study the mechanism of the therapeutic angiogenesis effect of bone marrow stromal cells (BMSCs) implantation on rat acute myocardial infarction models.The rat acute myocardial infarction models were made by coronary artery ligation and divided into 2 groups at random. In the experiment group, twice passaged BMSCs were labeled with BrdU and then implanted into the infarction region of the recipients in 4 weeks. The control group was the model rats received only DMEM injection. In control group, the hearts were harvested on the day 3, 7, 14, 28, 42 and 56. The infarction regions were examined to identify the angiogenesis and the expression of the VEGF and bFGF. In experiment group, the hearts were examined on the day 42 and 56 after AMI (the day 14 and 28 after cells implantation).Viable cells labeled with BrdU could be identified in host hearts. Histologic examination found most donor cells within the infarction region expressed fibroblastic and endothelial phenotype. The transplantation regions had a greater capillary density than the control regions did (14 +/- 4.7/HPF vs 6 +/- 2.4/HPF, P0.05). In the control group, the expression of VEGF and bFGF within the infarction regions peaked on day 7, and then decreased over time. In the experiment groups, the expression of bFGF and VEGF on the day 42 and 56 had a higher level than the control group did.The expression of VEGF and bFGF is significantly increased after cells therapy during the late phase of AMI. It indicates that BMSCs implantation promoted the angiogenesis is mediated by its differentiation into endothelium and the increased release of VEGF and bFGF.

Coronary artery disease (CAD) causes more than 700,000 deaths each year in China. Previous genome-wide association studies (GWAS) in populations of European ancestry identified several genetic loci for CAD, but no such study has yet been reported in the Chinese population. Here we report a three-stage GWAS in the Chinese Han population. We identified a new association between rs6903956 in a putative gene denoted as C6orf105 on chromosome 6p24.1 and CAD (P = 5.00 × 10⁻³, stage 2 validation; P = 3.00 × 10⁻³, P = 1.19 × 10⁻⁸ and P = 4.00 × 10⁻³ in three independent stage 3 replication populations; P = 4.87 × 10⁻¹², odds ratio = 1.51 in the combined population). The minor risk allele A of rs6903956 is associated with decreased C6orf105 mRNA expression. We report the first GWAS for CAD in the Chinese Han population and identify a SNP, rs6903956, in C6orf105 associated with susceptibility to CAD in this population.

Objective The objective of this study was to investigate the effect of simvastatin on TLR4,TNF-alpha and IL-6 expression in the myocardium and its relation to left ventricular (LV) remodelling in a rat model of myocardial infarction (MI) and to investigate the mechanism by which simvastatin improves LV remodelling in rats after MI. Methods and results The rat MI models were established by ligation of the left anterior descending coronary artery and divided into three groups: (I) an untreated MI group; (2) a group treated with simvastatin [40 mg/(kg/d)] for 4 weeks; (3) the sham group. Cardiac geometry and function were determined by echocardiography and infarct size was determined by the histomorphometric analysis; the expression ofTLR4 in the myocardium was measured by RT-PCR and western blotting;TNF-alpha and IL-6 levels in myocardial homogenate and serum were measured by ELISA. LVEDD and LVESD significantly increased and fractional shortening (FS) markedly decreased in the MI group. It was clear that simvastatin inhibited LV dilation and improved LV function after MI without affecting infarct size. The expression of TLR4, TNF-alpha and IL-6 in the myocardium significantly increased in the MI group and simvastatin markedly inhibits the expression of TLR4, TNF-alpha, and IL-6 in the myocardium after MI. Serum TNF-alpha and IL-6 levels between the MI group and the simvastatin group remained unchanged. Both in the MI group and the simvastatin group,TLR4 protein positively related to LVEDD and to the levels of TNF-alpha and IL-6 in the myocardium, respectively. Conclusion Amelioration of LV remodelling in rats after MI by simvastatin might be associated with its effect on the TLR4-mediated signalling pathway in the myocardium.

Astragalus polysaccharide (APS), the main extract from the traditional Chinese medicinal herb Astragalus membranaceus, has been reported to benefit the treatment of immune-inflammatory diseases and metabolic disorders. In atherosclerotic plaques, proinflammatory cytokines exert adverse effects on lipids thereby aggravating atherosclerosis. Recent evidence shows that tumor necrosis factor-alpha (TNF-alpha) can down-regulate the expression of ATP-binding cassette transporter A1 (ABCA1), which plays a vital role in reverse cholesterol transport and determines the process of atherosclerosis. In the present study, the effects of APS on ABCA1 expression, cholesterol effluent rate and total cholesterol content of THP-1 derived foam cells exposed to TNF-alpha were investigated. Compared with the foam cells exposed to TNF-alpha, ABCA1 expression was promoted in the presence of APS. Consequently the cholesterol effluent rate increased and the total cholesterol content decreased significantly. TNF-alpha could enhance the activity of nuclear factor-kappa B (NF-kappaB) in the foam cells. This effect could be attenuated by APS. These findings suggest that APS could protect ABCA1 against the lesion of TNF-alpha in THP-1 derived foam cells, which may contribute to its antiatherosclerotic properties.

Ketanserin (KT), a selective serotonin (5-HT) 2-receptor antagonist, reduces peripheral blood pressure by blocking the activation of peripheral 5-HT receptors. In this study electrophysiological method was used to investigate the effect of KT and potassium ion on Kv1.3 potassium channels and explore the role of blocker KT in the alteration of channel kinetics contributing to the potassium ion imbalances.Kv1.3 channels were expressed in xenopus oocytes, and currents were measured using the two-microelectrode voltage-clamp technique.KCl made a left shift of activation and an inactivation curve of Kv1.3 current and accelerated the activation and inactivation time constant. High extracellular [K(+)] attenuated the blockade effect of KT on Kv1.3 channels. In the presence of KT and KCl the activation and inactivation time constants were not influenced significantly no matter what was administered first. KT did not significantly inhibit Kv1.3 current induced by tetraethylammonium (TEA).KT is a weak blocker of Kv1.3 channels at different concentrations of extracellular potassium and binds to the intracellular side of the channel pore. The inhibitor KT of ion channels is not fully effective in clinical use because of high [K(+)](o) and other electrolyte disorders.

Adiponectin, an adipocyte-specific protein, matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) play a crucial role in arteriosclerosis and plaque disruption. The present study was designed to elucidate the relationship of adiponectin and the ratio of MMP-9/TIMP-1 and their effects on the stability of plaque in acute coronary syndrome (ACS).The concentrations of adiponectin, MMP-9, TIMP-1 and interleukin-10 were analyzed using ELISA in 56 consecutive unselected patients divided into two groups, stable angina (n=13) and ACS (n=43), and were compared with 19 healthy control subjects. The 56 patients were also angiographically studied and divided into two groups, simple lesion (n=22) and complex lesion (n=34), based on coronary plaque morphology.The ratio of MMP-9/TIMP-1 showed significantly higher values in the ACS group compared with the control group (0.22+/-0.10 versus 0.11+/-0.03; P0.001). Adiponectin was negatively correlated with the ratio of MMP-9/TIMP-1 (r=--0.332; P=0.008) and positively correlated with interleukin-10 (r=0.651; P=0.001). Multivariate logistic regression analysis showed that adiponectin (P=0.046) and MMP-9/TIMP-1 (P=0.044) are independent predictors for ACS, and MMP-9/TIMP-1 (P=0.013) is an independent predictor for complex lesion morphology plaques.In the present study, it was found that adiponectin has a negative relationship with the ratio of MMP-9/TIMP-1 in patients with ACS, and that the ratio of MMP-9/TIMP-1 is an independent predictor of the stability of atherosclerotic plaque and the severity of coronary atherosclerosis.

The novel chemokine CXCL16 is involved in the development of atherosclerosis and coronary artery disease (CAD). However, the role of CXCL16 in atherosclerosis remains uncertain. This study was designed to investigate the relationship between CXCL16 and the severity of coronary artery stenosis.Using ELISA, we assayed the plasma CXCL16 concentration in 16 stable angina pectoris (SAP) patients, 53 acute coronary syndrome (ACS) patients, and 19 control patients. All patients underwent coronary angiography after admission. They were divided into four groups according to the quartile of CXCL16 level. Characteristics and the relationship between CXCL16 and the elements were studied in each group.CXCL16 levels in the ACS group were higher than controls and SAP group (p0.01 vs. controls; p0.05 vs. SAP group). Gensini score in the highest quartile group of CXCL16 level (group IV, CXCL162.21 ng/mL) was significantly higher than in the lowest quartile group of CXCL16 level (group I, CXCL16or = 1.43 ng/mL) (p0.001). Gensini score in group II (1.43 ng/mLCXCL16or = 1.72 ng/mL) and group III (1.72 ng/mLCXCL16or = 2.21 ng/mL) were also higher than in group I (p0.05, p0.01). In addition, CXCL16 level had a positive correlation with Gensini score (r = 0.519, p0.001).CXCL16 levels are positively associated with the severity of coronary artery stenosis. Activity level of CXCL16 in human plasma appears to be a good biomarker for epidemiological and clinical application in CAD.

The study was purposed to investigate the immune regulatory effects of human bone marrow mesenchymal stem cells (hMSCs) on Foxp3 expressing CD4(+)CD25(+) regulatory T cells and to explore the mechanism of immune modulation by hMSCs. Human MSCs were isolated and expanded from bone marrow cells, and identified with cell morphology, and the phenotypes were assessed by immunohistochemistry. Human peripheral blood mononuclear cells (hPBMNCs) were prepared by centrifugation on a Ficoll Hypaque density gradient. The hMSCs (1 x 10(3), 1 x 10(4), 1 x 10(5)) were added into wells containing hPBMNCs (1 x 10(6)) from an unrelated donor in the presence of rhIL-2. After 5 days of co-culture, the percentage of CD4(+)CD25(+) T cells was detected by flow cytometry. T cell proliferation was assessed by [(3)H] thymidine incorporation using a liquid scintillation counter. The expression of Foxp3 in CD4(+)CD25(+) T cells was detected by reverse transcription polymerase chain reaction (RT-PCR). Cytokines (TGF-beta, IL-12, IFN-gamma, IL-10) concertrations of cultured supernatants were measured with ELISA. The results indicated that in all the experiments, the presence of hMSCs with hPBMNCs resulted in a statistically significant decrease in T cell proliferation, in dose-dependent manner. The increase of percentage of CD4(+)CD25(+) T cells in the peripheral CD4(+) T cell was observed after coculturing lymphocytes with hMSCs (p0.01). The expression of Foxp3-mRNA (Foxp3/beta-actin) in hMSCs groups was significantly higher than that in the control and was negatively associated with the value of CPM representing T proliferation. The levels of TGF-beta and IL-10 were higher in hMSCs groups than that in the control, and the levels of TGF-beta and IL-10 correlated positively with Foxp3-mRNA expression and the percentage of CD4(+)CD25(+) T cells. However, the secretion of IL-12 and IFN-gamma was significantly attenuated by hMSCs coculture, and there was no correlation with Foxp3-mRNA expression and the percentage of CD4(+)CD25(+) T cells. It is concluded that the Foxp3 expressing regulatory T cells may play an important role in the immune regulatory by hMSCs. Its mechanism is related to that the hMSCs-mediated TGF-beta and IL-10 convert CD4(+)CD25(-) T cells into CD4(+)CD25(+) T regulatory T cells, which specifically inhibits the proliferation of T cells.

Atherosclerosis is a chronic inflammatory disease and interleukins are considered to play a key role in the chronic vascular inflammatory response that is typical of atherosclerosis. The serum levels of several of these cytokines have been found to positively correlate with coronary arterial disease and its sequelae.The aim of our study was to evaluate the levels of a comparatively new cytokine IL-17, in patients with stable and unstable coronary artery disease in order to assess whether unstable coronary artery disease patients had higher IL-17 levels.We analyzed the concentrations of IL-17, IL-6, IL-8 and IL-10 using enzyme-linked immunosorbent assay and heat-sensitive C-reactive protein using latex particle-enhanced immunoturbidimetry in 58 consecutive unselected patients divided into three groups: stable angina (n=14), unstable angina (n=24) and acute myocardial infarction (n=20). We further compared them with 20 healthy controls. These 58 patients were also angiographically studied and divided into two groups: simple lesion (n=22) and complex lesion (n=36), on the basis of the coronary plaque morphology.Our results show increased concentrations of the proinflammatory cytokines IL-17, IL-6, IL-8 and heat-sensitive C-reactive protein, and decreased concentration of IL-10 in plasma of unstable angina and acute myocardial infarction patients. Plasma concentration of IL-17 was also positively correlated with plasma concentrations of IL-6 and heat-sensitive C-reactive protein. Our findings further showed that IL-17 values were higher in patients having angiographically visible complex types of lesions but no difference was observed between complex and simple lesion morphology patients.In conclusion, these findings point towards a role of inflammation in the form of increased activity of IL-17, IL-6 and IL-8 in patients of unstable angina and acute myocardial infarction and thus suggest that IL-17-driven inflammation may play a role in the promotion of clinical instability in patients with coronary artery disease.

This study aimed to investigate the effects of folate on the monocyte chemoattractant protein-1 (MCP-1) expression and release in rats with hyperhomocystinemia induced by ingestion of excess methionine.Thirty male Sprague-Dawley rats (200+/-20 g) were randomly divided into three groups (n=10 for each group): control group (Control), high-homocystinemia (Hhcy) group, and folate treatment (FA) group. They were fed with a normal regular diet, enriched by 1.7% methionine plus 1.7% methionine and 0.006% folate for 45 days. Our study showed the following: (a) A high methionine diet for 45 days is sufficient to induce hyperhomocystinemia; folate supplementation to the rats fed the high-methionine diet prevented an elevation homocysteine (Hcy) levels in the blood (P.01). (b) Compared with the Control group, the Hhcy group had elevated plasma levels of MCP-1, and Hcy was significantly correlated with MCP-1 (P.05). (c) The protein and mRNA expression of MCP-1 in the aorta was higher in rats from the Hhcy group than in rats from the Control group. (d) Most important, after folic acid supplementation, the lowering of Hcy levels was accompanied by a marked reduction of MCP-1 expressed in aortae and released from plasma and peripheral blood mononuclear cells (PBMCs) stimulated by oxidized low-density lipoprotein (P.05, P.01).Folic acid supplementation not only can blunt the rise in Hcy and reduce MCP-1 released from both plasma and PBMCs of rats with hyperhomocystinemia but also can downgrade MCP-1 expression in the aorta of rats with hyperhomocystinemia.

To evaluate the time course of granulocyte-colony-stimulating-factor (G-CSF), estrogen and various doses of atorvastatin on endothelial progenitor cells (EPCs) mobilization.A total of 48 male New Zealand White rabbits were treated with placebo, estrogen (0.25 mg.k(-1).d(-1)), Atorvastatin (2.5, 5, or 10 mg) and G-CSF (50 microg/rabbit/d), respectively. Peripheral EPCs number was surveyed weekly for 4 weeks by FACS analysis (double-positive for PE-CD34/FITC-CD133) and under fluorescent microscope (double-positive for FITC-UEA-1/Dil-acLDL). Serum nitric oxide (NO) and lipids were also measured at the third week.Peripheral EPCs was significantly increased in G-CSF treated animals and remained constant for 4 weeks compared to placebo treated animals. Atorvastatin increased peripheral EPCs dose-dependently from 2.5 to 5 mg and peaked at the third week while peripheral EPCs number was not affected by 10 mg.k(-1).d(-1) atorvastatin during the first 3 weeks and was significantly higher only in the fourth week compared to placebo group. Estrogen also significantly increased peripheral EPCs at the third and fourth week compared to placebo group. At the third week, serum NO was similar in G-CSF group, significantly higher in atorvastatin 5 mg.k(-1).d(-1) and estrogen groups while significantly lower in atorvastatin 10 mg.k(-1).d(-1) group compared to placebo group. Serum lipids were similar among various groups.Atorvastatin, estrogen and G-CSF could mobilize EPCs. The mobilization efficacy is as follows: G-CSFatorvastatin 5 mg.k(-1).d(-1)estrogenatorvastatin 2.5 mg.k(-1).d(-1)atorvastatin 10 mg.k(-1).d(-1). NO might partly contribute to the mobilizing effect of estrogen and atorvastatin.

To investigate the function of dendritic cells (DC) in patients with unstable angina pectoris (UAP) and the effects of atorvastatin on it.27 patients with UAP were divided into two groups treated respectively with regular pharmacotherapy and regular pharmacotherapy plus atorvastatin. PBMC from the UAP patients (before and 2 weeks after the treatment) and 11 healthy subjects were incubated and induced to mature DC in a completed medium containing GM-CSF and IL-4. Flow cytometric analysis was used to detect the expression of co-stimulating factor CD86 (B7-2) on DC. The stimulating capacity of DC was determined in allogenic mixed lymphocyte reaction (MLR). ELISA was used to analyze the level of cytokines (IL-1beta, IL-6, IL-10 and TNF-alpha) in the medium of MLR. Relationship of expression of CD86 to risk factors and blood CRP level was also analyzed.When compared with normal group, CD86 on DC was much more expressed in UAP patients; the stimulating capacity of DC in MLR was higher; T lymphocytes in MLR secreted higher levels of pro-inflammation cytokines (IL-1beta, IL-6 and TNF-alpha) and lower level of anti-inflammation cytokine (IL-10). Blood LDL-C before treatment was positively related to the expression of CD86. Atorvastatin inhibited the function of DC and lowered blood level of CRP and CD86, the levels of which were significantly positively correlated.DC in UAP are activated, which may play an important role in initiating immune reaction in the plaque. LDL-C may be one of the activators of DC; inhibitory effect of atorvastatin on inflammation in UAP may be due to its inhibition on DC.