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Aims: γ-aminobutyric acid (GABA), the principal inhibitory neurotransmitter, acts on GABA receptors to play an important role in the modulation of macrophage functions. The present study examined the effects of GABA and a GABA receptor agonist on modulating cholesterol-metabolism-associated molecules in human monocyte-derived macrophages (HMDMs). Methods: ORO stain, HPLC, qRT-PCR, Western blot and EMSA were carried out using HMDMs exposed to ox-LDL with or without GABAergic agents as the experimental model. Results: GABA and topiramate reduced the percentage of cholesterol ester in lipid-laden HMDMs by down-regulating SR-A, CD36 and LOX-1 expression and up-regulating ABCA1, ABCG1 and SR-BI expression in lipid-laden HMDMs. The production of TNF-a was decreased in GABA-and topiramate-treated lipid-laden HMDMs, and levels of interleukin (IL)-6 did not change. The activation of two signaling pathways, p38MAPK and NF-γB, was repressed by GABA and topiramate in lipid-laden HMDMs. Conclusion: GABA and topiramate inhibit the formation of human macrophage-derived foam cells and may be a possibility for macrophage targeted therapy of atherosclerotic lesions.

Aims: In this study, we aimed to clinically and genetically characterize LVNC patients and investigate the prevalence of variants in known and novel LVNC disease genes. Introduction: Left ventricular non-compaction cardiomyopathy (LVNC) is an increasingly recognized cause of heart failure, arrhythmia, thromboembolism, and sudden cardiac death. We sought here to dissect its genetic causes, phenotypic presentation and outcome. Methods and results: In our registry with follow-up of in the median 61 months, we analysed 95 LVNC patients (68 unrelated index patients and 27 affected relatives; definite familial LVNC = 23.5%) by cardiac phenotyping, molecular biomarkers and exome sequencing. Cardiovascular events were significantly more frequent in LVNC patients compared with an age-matched group of patients with non-ischaemic dilated cardiomyopathy (hazard ratio = 2.481, P = 0.002). Stringent genetic classification according to ACMG guidelines revealed that TTN, LMNA, and MYBPC3 are the most prevalent disease genes (13 patients are carrying a pathogenic truncating TTN variant, odds ratio = 40.7, Confidence interval = 21.6-76.6, P

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.

This study will explore the autoantibodies against AT1-receptor and alpha1-adrenergic receptor in patients with hypertension. Forty normotensives and 194 patients with hypertension were recruited for participation in this study. All patients accepted systemic combination drug treatment for antihypertension. According to the treatment results and the definition of refractory hypertension, the patients were divided into two groups: a refractory hypertension group and a non-refractory hypertension group. The epitope of the 2nd extracellular loop of type 1 angiotensin (AT1) receptor and alpha1-adrenergic receptor were synthesized and used as antigens to screen the autoantibodies against AT1-receptor and alpha1-adrenergic receptor by ELISA. The plasma renin activity and concentration of angiotensin II and catecholamine were also examined. The positive rates of the autoantibodies against AT1-receptor and alpha1-adrenergic receptor in patients with hypertension, 26.8% (52/194) and 25.3% (49/194), respectively, were higher than those in normotensives (7.5% and 5%)(p < 0.01). Further investigation showed that the frequencies of the autoantibodies against AT1-receptor and alpha1-adrenergic receptor in patients with refractory hypertension, 42.9% (42/98) and 36.7% (36/98), respectively, were higher than those in patients with non-refractory hypertension under systematic treatment (10.4% and 13.5%)(p < 0.01). The levels of circulating angiotensin II, catecholamine, proteinuria and serum creatine were also higher in the refractory hypertension group than in the non-refractory hypertension group. The findings showed that the frequencies of autoantibodies against AT1-receptor and alpha1-adrenergic receptor were higher in patients with hypertension, particularly in those with refractory hypertension, and that these autoantibodies might play a role in the pathogenesis of hypertension.

Curcumin, the principal active component of turmeric, has long been used to treat various diseases in India and China. Recent studies show that curcumin can serve as a therapeutic agent for autoimmune diseases via a variety of mechanisms. Effector memory T cells (T(EM), CCR7⁻ CD45RO⁺ T lymphocyte) have been demonstrated to play a crucial role in the pathogenesis of T cell-mediated autoimmune diseases, such as multiple sclerosis (MS) or rheumatoid arthritis (RA). Kv1.3 channels are predominantly expressed in T(EM) cells and control T(EM) activities. In the present study, we examined the effect of curcumin on human Kv1.3 (hKv1.3) channels stably expressed in HEK-293 cells and its ability to inhibit proliferation and cytokine secretion of T(EM) cells isolated from patients with MS or RA. Curcumin exhibited a direct blockage of hKv1.3 channels in a time-dependent and concentration-dependent manner. Moreover, the activation curve was shifted to a more positive potential, which was consistent with an open-channel blockade. Paralleling hKv1.3 inhibition, curcumin significantly inhibited proliferation and interferon-γ secretion of T(EM) cells. Our findings demonstrate that curcumin is able to inhibit proliferation and proinflammatory cytokine secretion of T(EM) cells probably through inhibition of hKv1.3 channels, which contributes to the potency of curcumin for the treatment of autoimmune diseases. This is probably one of pharmacological mechanisms of curcumin used to treat autoimmune diseases.

To investigate the correlation between the levels of serum IFN-γ and RANTES (regulated upon on activation on normal T cell expressed and secreted) and rabbit atherosclerotic plaque stability.30 male New Zealand rabbits were randomly divided into three groups: control group, stable atherosclerotic plaque group(AS group) and vulnerable atherosclerotic plaque group(VAP group), with 10 rabbits in a group. The control group was given normal diet while the AS group and the VAP group were given high-fat diet for 12 weeks. According to literature method pharmacological triggers inducing the vulnerable atherosclerotic plaque formation in the VAP group. Fasting blood was extracted from ear medium artery about 2 mL at week-0 and the 12th week, serum total cholesterol, triglyceride and high density lipoprotein cholesterol were detected by enzymatic method, and low density lipoprotein cholesterol was calculated by Friedwald formula. All animals were executed after they were fed by injected excessive Phenobarbital sodium at ear vein for 12 weeks. Before executed, ear medium artery blood was taken to detect the levels of serum IFN-γ and RANTES by ELISA.The corrected plaque area and vulnerability index were calculated by Masson staining and its correlation coefficient with inflammatory factors were measured.The level of serum IFN-γ at the AS group and the VAP group, compared with the control group, was significantly increased(all P0.01), at the same time, the level of serum IFN-γ in the VAP group was significantly higher than in the AS group(P0.01). About the level of serum RANTES there was no obvious difference when the AS group was compared with the control group(P0.05). The level of serum RANTES in the VAP group was higher than in the AS group and the control group(all P0.01). Regarding corrected plaque area and vulnerability Index, the VAP group was significantly higher than the AS group (P0.01). In the AS group and the VAP group, the serum concentrations of IFN-γand RANTES exhibited a positive correlation with corrected plaque area and vulnerability Index (P0.05).IFN-γ and RANTES may be inflammatory marker about atherosclerotic vulnerable plaque, and their serum concentration can be used to evaluate the atherosclerotic plaque instability.

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.

To investigate the association of -689C/T polymorphism in the peroxisome proliferator-activated receptor-gamma2 (PPARgamma2) promoter with myocardial infarction (MI).This is a case-control study, which included 194 subjects with MI and 693 subjects without MI in nondiabetic Han population in Wuhan. Polymerase chain reaction-restriction fragment length polymorphism was used to determine the -689C--T substitution.The CC,CT, and TT genotype frequencies of -689C/T polymorphism were 88.1%,11.9%,and 0.0 in MI patients and 93.1%,6.6%,and 0.3% in controls, respectively (CC vs. CT+TT, P=0.025). The -689T allele was an independent risk factor for MI (OR=2.125, 95%CI: 1.206-3.744, P=0.009) after adjusting for age,sex,waist circumference,body mass index, smoking, alcohol drinking, physical activities, systolic blood pressure, diastolic blood pressure, fasting blood glucose, total cholesterol, triglyceride, level. The -689T allele carriers had significantly higher TC levels than noncarriers [(5.05+/-1.16) mmol/L vs. (4.78+/-1.05) mmol/L, P=0.004] in the total population.The PPARgamma2 promoter -689C/T polymorphism is associated with an increased risk of MI.

To investigate the changes of guinea pig heart electrophysiological properties caused by increasing left ventricular preload, and to assess the effects of tetradrine on these changes.Working model preparation of guinea pig hearts in vitro was used, and the preload of left ventricle was increased by adjusting the prefusion pressure of left atria. The changes of heart electrophysiologic parameters including monophasic action potential duration (MAPD90), monophasic action potential amplitude (MAPA), effective refractory period (ERP) and ventricular fibrillation threshold (VFT) were observed before and after altering the preload of left ventricle, and compared in the absence and presence of tetradrine, streptomycin or verapamil.The rising of left ventricular preload led to shortening of MAPD90, ERP, and to descent of MAPA, VFT (all P0.01). Both Tetradrine and streptomycin inhibited these changes of heart electrophysiologic parameters caused by elevation of left ventricular afterload (all P0.01). In contrast, verapamil had no effects on the preload-related electrophysiological changes (all P0.05).Electrophysiologic changes caused by increasing left ventricular preload may be inhibited by tetrandrine, through inhibition of stretch-activated ion channels.

The aim of this article was to investigate the dependence of ventricular wallstress-induced refractoriness changes on pacing cycle lengths and its mechanism in anaesthetized rabbits. The rabbit heart preparation was used. The left ventricular afterload was increased by partially clipping the root of the ascending aorta. The changes in effective refractory periods (ERP) induced by the left ventricular afterload rising were examined at different pacing cycle lengths (1000, 500, 300 and 200 ms). In addition, the effect of streptomycin on these changes was also observed. The results are as follows: (1) The rising of left ventricular afterload led to marked changes in ERP at rapidly pacing cycle lengths (300 ms, 21+/-5 ms, 17.0%; 200 ms, 19+/-3 ms, 18.8%. P0.01) than at slow ones (1000 ms, 3+/-2 ms, 1.5%; 500 ms, 7+/-3 ms, 4.0%. P0.05); (2) Streptomycin inhibited the changes caused by the left ventricular afterload rising at pacing cycle lengths 300 ms and 200 ms (P0.05). It is suggested that ventricular wallstress-induced refractoriness changes are pacing cycle length-dependent, and the effect of streptomycin appears to be consistent with the inhibition of stretch-activated ion channels.

The aim of this study was to investigate the protective effect of adenosine (ADO) on cardiomyocytes following hypoxia/reoxygenation (H/R) and its molecular mechanism. Primary cultured cardiomyocytes of neonatal rats were divided into two groups, namely H/R (control) and ADO (1.0 micromol/L) groups. The morphologic changes in cardiomyocytes were observed under an inverted phase-contrast microscope. The following parameters of the two groups were determined: lactate dehydrogenase (LDH) activity, intracellular calcium concentration and malondialdehyde (MDA) content. Tumor necrotic factor (TNF-alpha) assay was performed using an ELISA kit and NF-kappaB in the nucleus was analyzed by electrophoretic mobility shift assay (EMSA). The results are as follows: (1) after H/R injury, cardiomyocytes contracted, tending to get round in shape and its pseudopods decreased, while marked morphological changes were not observed in ADO group; (2) LDH leakage maintained at a lower level in ADO group than that in the control group during H/R (both P0.01); (3) ADO significantly reduced the concentration of calcium in cells and prevented calcium overload during H/R (both P0.01); (4) ADO markedly reduced the content of MDA during H/R (both P0.01); (5) ADO inhibited the production of TNF-alpha during H/R (both P0.01); and (6) ADO down-regulated NF-kappaB binding activity of cardiomyocytes during H/R (both P0.01) The results suggest that (1) exogenous ADO attenuates H/R injury of cultured cardiomyocytes; (2) exogenous ADO inhibits the production of TNF-alpha after H/R injury; (3) exogenous ADO prevents the activation of NF-kappaB, which may be the molecular mechanism of down-regulation of TNF-alpha expression.

Isolated, spontaneously beating rabbit sinoatrial node cells were subjected to longitudinal stretch, using carbon fibers attached to both ends of the cell. Their electrical behavior was studied simultaneously in current-clamp or voltage-clamp mode using the perforated patch configuration. Moderate stretch ( approximately 7%) caused an increase in spontaneous beating rate (by approximately 5%) and a reduction in maximum diastolic and systolic potentials (by approximately 2.5%), as seen in multicellular preparations. Mathematical modeling of the stretch intervention showed the experimental results to be compatible with stretch activation of cation nonselective ion channels, similar to those found in other cardiac cell populations. Voltage-clamp experiments validated the presence of a stretch-induced current component with a reversal potential near -11 mV. These data confirm, for the first time, that the positive chronotropic response of the heart to stretch is, at least in part, encoded on the level of individual sinoatrial node pacemaker cells; all reported data are in agreement with a major contribution of stretch-activated cation nonselective channels to this response.