En-Zhi Jia

The common variant in the GSTM1 and GSTT1 genes is related to markers of oxidative stress and inflammation in patients with coronary artery disease: a case-only study.

Recent studies suggest that the common variant in the GSTM1 and GSTT1 genes modifies the risk of coronary artery disease (CAD), however, it is unclear whether the risk of CAD modulated by variants in the GSTM1 and GSTT1 genes was associated with alterations of indices of oxidative stress and inflammation. Our study is an attempt to provide insight into the role of GST genetic variant and markers of oxidative stress and inflammation in CAD patients. A total of 719 Chinese CAD patients were successfully genotyped. Plasma total antioxidant status (TAOS), glutathione(GSH), C-reactive protein (CRP), fibrinogen (FIB) and white blood cell count (WBC) were determined to evaluate the oxidative stress and inflammatory response. The correlations between GSTM1/GSTT1 genotypes and alterations of indices of oxidative stress and inflammation were analyzed. We found GSTM1-0/GSTT1-0 subjects had higher CRP and FIB and lower TAOS compared to patients with wild-type GSTM1/GSTT1 genes. A stepwise elevations in age, the incidences of hypertension and diabetes mellitus, levels of FIB and the number of WBC were associated with increased number of stenosed vessels. Reductions of plasma TAOS and GSH were associated with increased number of stenosed vessels. Our results suggest that GST polymorphisms maybe modify the effect on markers of oxidative stress and inflammation in Chinese CAD patients.

Testosterone is negatively associated with the severity of coronary atherosclerosis in men.

This study aimed to determine whether plasma testosterone is associated with the severity of coronary atherosclerosis in a group of 803 men who underwent elective coronary angiography. Testosterone levels were measured in 803 male patients who were categorized into three groups according to testosterone level tertiles. All patients underwent elective coronary angiography, and the severity of coronary artery disease (CAD) was determined by the Gensini score. Moreover, patients were classified into two groups according to Gensini scores (score ≤26 and score >26) using the median values as cutoff points. The plasma testosterone levels were measured by an ELISA kit. The level of testosterone was negatively associated with the Gensini score (r=-0.188; P=0.000). A multiple linear regression analysis revealed that testosterone was an independent risk factor for the Gensini score (β=-0.110; P=0.002) after adjusting for confounding covariates. In a multivariate logistic regression model, the severity of CAD was shown to be significantly lower in the third tertile (highest) of testosterone compared to the first tertile (lowest) of testosterone (odds ratio (OR)=0.465; 95% confidence interval (CI): 0.327-0.662; P=0.000). In this study, patients with lower testosterone levels had higher Gensini scores in a group of 803 men who underwent elective coronary angiography. Additional studies are needed to clarify the direction of causality and possible underlying mechanisms.

Toxic effects of a high dose of non-ionic iodinated contrast media on renal glomerular and aortic endothelial cells in aged rats in vivo

Iodinated contrast media (CM) can induce apoptosis and necrosis of renal tubular cells. The injuries of endothelial cells induced by CM on the systemic condition have not been fully understood. To assess the toxic effects of non-ionic CM on the glomerular and aortic endothelial cells, iopromide and iodixanol, two kinds of representative non-ionic CM, were used for the in vivo study. Sixty aged rats were respectively received the agents or normal sodium intravascularly. No obvious apoptosis and morphological change was detected in the glomerular and aortic endothelial cells apart from renal tubules after CM administration. However, expressions of the nitric oxide synthase (eNOS) in glomerular endothelium were decreased at 12h after CM injection. Furthermore, plasma creatinine and endothelin-1 were increased and plasma nitric oxide (NO) was decreased significantly after CM administration. However, we failed to observe the significant increase of plasma von Willebrand Factor. These results suggest that non-ionic iodinated CM do not induce apoptosis and necrosis of glomerular and aortic endothelial cells in vivo. Decreased eNOS expression and increased plasma endothelin-1 may be involved in non-ionic iodinated CM-induced endothelial dysfunction and kidney injury.

Association of SNP Rs6903956 on Chromosome 6p24.1 with Angiographical Characteristics of Coronary Atherosclerosis in a Chinese Population

Objective To explore the association between rs6903956 and severity of coronary artery disease (CAD) in a Chinese population. Methods A cohort of 1075 consecutive patients who underwent coronary arteriography for suspected or known coronary atherosclerosis was enrolled in our study. Coronary atherosclerosis severity was defined by Gensinis Score System and counts of diseased vessels. Results Gensini score frequencies and counts of diseased vessels differed among GG, AG, AA genotype groups at the rs6903956 locus (p = 0.025 for Gensini score frequencies vs. p = 0.024 for counts of diseased vessels, respectively). A univariate logistic regression analysis revealed that the genotype distribution of this SNP was associated significantly with angiographical characteristics of coronary atherosclerosis risk (p = 0.030, odds ratio (OR) = 1.444, 95% confidence interval (CI) = 1.036∼2.013 for AG vs. GG; p = 0.021, OR = 5.896, 95% CI = 1.299∼26.750 for AA vs. GG and p = 0.007, OR = 1.564, 95% CI = 1.132∼2.162 for combined (AG+AA) vs. GG). A multivariate logistic regression analysis indicated that the genotype distribution of the rs6903956 polymorphism be associated significantly with the angiographical characteristics of coronary atherosclerosis risk (p = 0.004, OR = 1.578, 95% CI = 1.155∼2.154 for GG vs. AG vs. AA; p = 0.013, OR = 1.541, 95% CI = 1.097∼2.163 for GG vs. GA+ AA). A stratification analysis revealed that male subjects and smoking subjects had a higher frequency of the rs6903956 heterozygous mutant among higher Gensini score subjects than among lower Gensini score subjects (p = 0.023, OR = 1.579, 95% CI = 1.064∼2.344 for male subgroup; p = 0.005, OR = 2.075, 95% CI = 1.249∼3.448 for smoking subgroup). Conclusions Allele A is a risk factor for CAD and the G-to-A allele substitution may underlie the association between rs6903956 and CAD.

Renin-Angiotensin-Aldosterone System Gene Polymorphisms and Coronary Artery Disease: Detection of Gene-Gene and Gene-Environment Interactions

Objective: The objective of this study was to explore the association between coronary artery disease and genetic polymorphisms of the renin–angiotensin–aldosterone system (RAAS) pathway. In addition, we examined the interactions between demographic and lifestyle risk factors (environmental factors including age, sex, smoking status, alcohol intake) and RAAS polymorphisms on disease risk. Methods: A total of 1089 subjects who underwent coronary angiography were enrolled in this study. Eight RAAS polymorphisms were genotyped in this population: the G2350A (rs4343) polymorphism in exon 17 of the angiotensin converting enzyme (ACE) gene, 1166A→C (rs5186) and 573C/T (rs5182) in the angiotensin II type 1 receptor (AGTR1) gene, the -344C→T transversion (rs1799998) in the aldosterone synthase (CYP11B2) gene, and the G-217A (rs5049), G-6A (rs5051), M235T (rs699; T4072C), and T174M (rs4762; C3889T) polymorphisms in the angiotensinogen (AGT) gene. Subjects with coronary heart disease were defined as those with at least 50% stenosis in at least one major coronary artery, and, the severity of coronary atherosclerosis was defined by the Gensini scoring system. Results: Compared to the subjects with AA genotype, the subjects with AG + GG genotype of rs1799998 had significant lower gensini score (p=0.029). After adjusting for age, gender, cigarette smoking, and alcohol intake status, the AG genotype (OR 0.717 95%CI 0.541–0.950, p=0.021) and the AG + GG genotype (OR 0.730 95%CI 0.559–0.954, p=0.021) distributions of rs1799998 were significantly different between the cases and controls compare to the AA genotype. Subjects with three at-risk loci had increased risk of coronary artery disease compared to subjects carrying 0 or 1 risk-associated polymorphism (OR [95% CI]:1.579 [1.077–2.316], p=0. 019), and the significance of the association was not reduced after adjusting for age, sex, cigarette smoking, or alcohol intake (adjusted OR [95% CI]: 1.673 [1.116–2.507], p=0.013). The results of multifactor-dimensionality reduction analysis revealed an interaction effect of CYP11B2 -344C→T, age, and smoking status on the risk of coronary heart disease (training OR [95% CI]: 3.7685 [2.8463–4.9895], p<0.0001; testing OR [95% CI]: 2.7583 [1.2038–6.3203], p=0.015). Conclusions: Subjects who carried the G allele of the rs1799998 polymorphism significantly associated with coronary heart disease and severity of coronary atherosclerosis estimated by the Gensini score in the whole population of the study. And, multiple RAAS gene polymorphisms are associated with coronary artery disease. The interaction of the CYP11B2 -344C→T polymorphism (rs1799998), age, and smoking status is also associated with enhanced risk of coronary artery disease.

Genetic variant in visfatin gene promoter is associated with decreased risk of coronary artery disease in a Chinese population.

BACKGROUND Visfatin is a newly identified pro-inflammatory adipokine expressed predominantly in visceral fat. Previous studies have suggested a role for visfatin in low-grade inflammation and regulation of lipid metabolism. Most recently, a genetic polymorphism -1535C>T located in the visfatin gene promoter has been identified, and suggested to be associated with the regulation of visfatin expression, lipid levels. However, it is unclear whether this polymorphism has a linkage with CAD. METHODS We conducted a hospital-based case-control study with 257 CAD patients and 292 controls to examine the potential association of the Visfatin -1535C>T polymorphism with CAD. RESULTS The frequencies of the CC, CT, and TT genotypes in cases were significantly different from those of controls (chi2=6.223, P=0.045). Subjects with the variant genotypes (CT+TT) had a 40% decreased risk of CAD relative to CC carriers (adjusted OR=0.60, 95%CI=0.40-0.89). Furthermore, the adjusted OR of a TT genotype for CAD was 0.52 (95%CI=0.31-0.87). There was a significant association between Visfatin -1535C>T polymorphism and triglyceride levels in both CAD patients and controls (P=0.003, 0.018, respectively). In stratified analyses, the T allele was significantly associated with reduced risk of CAD in males, subjects with age <59years, and non-smokers. Moreover, a borderline statistical significance (P=0.058 for trend) was observed between the variant genotypes and severity of CAD. CONCLUSION Our results suggested that Visfatin -1535C>T polymorphism might be associated with reduced risk of CAD in a Chinese population.

Interaction between microRNA expression and classical risk factors in the risk of coronary heart disease.

The aim of this study was to identify the synergistic effect of microRNA expression with classical risk factors of coronary heart disease (CHD) and to explore their diagnostic value for coronary stenotic lesions in subjects with CHD. Plasma samples were obtained from 66 subjects with CHD and from 58 control individuals. A quantitative reverse-transcription PCR (RT-qPCR) assay was conducted to confirm the relative expressions of the known CHD-related miRNAs. The severity of coronary atherosclerosis was based on the Gensini scoring system. The expression of miR-125b in plasma of the CHD group was lower than that of the non-CHD group (0.14 ± 0.09 vs. 0.18 ± 0.10, p = 0.055), and the miR-125b levels significantly decreased following an increasing Gensini score (P = 0.037). Spearman correlation analyses indicated the Gensini score was negatively associated with miR-125b (r = −0.215, p = 0.017). Of all the miRNAs, miR-125b showed the lowest AUC (0.405; 95% CI: 0.305 ~ 0.506, p = 0.070). We found several synergistic effects between miR-125b and classical risk factors, such as age, sex, CR, FBG and HDL-C; the proportion of CHD attributable to the interaction of miR-125b and age was as high as 80%. Therefore, miR-125b was shown to play an important role in individual’s susceptibility to developing CHD.

Flavonols intake and the risk of coronary heart disease: a meta-analysis of cohort studies

OBJECTIVE Prospective cohort are inconsistent regarding the association between flavonols intake and the risk of coronary heart disease (CHD). The aim was to perform a meta-analysis to determine whether an association exists between them in observational studies. METHODS We searched PUBMED and EMBASE databases for studies conducted from 1966 through January 2012. Data were independently abstracted by 2 investigators using a standardized protocol. Study-specific risk estimates were combined by using a random-effects model. RESULTS A total of nine general population cohorts with 216,908 participants and more than 5249 CHD cases were included in the meta-analysis. The summary relative risk (RR) did not indicate a significant association between the highest flavonols intake and reduced risk of CHD (summary RR: 0.91; 95% CI: 0.83, 1.01). Furthermore, no significant association was found through the dose-response analysis (an increment of 20mg/day, summary RR: 0.96; 95% CI: 0.90, 1.03). CONCLUSIONS Our results do not support a protective role of flavonols intake against CHD.

Circular RNAs promote TRPM3 expression by inhibiting hsa-miR-130a-3p in coronary artery disease patients

We investigated the differential expression of circular RNAs (circRNAs) in plasma samples from three coronary artery disease (CAD) patients to identify putative therapeutic targets. We identified 24 differentially expressed circRNAs (18 up-regulated and 6 down-regulated) and 7 differentially expressed mRNAs (6 up-regulated and 1 down-regulated) in CAD patients based on competing endogenous RNA (ceRNA) microarray analysis. MiR-221(p = 0.001), miR-155(p = 0.049), and miR-130a (p = 0.001) were downregulated in CAD patients based on qRT-PCR analysis of another independent population of 932 study subjects (648 CAD subjects and 284 controls). We constructed a hsa-miR-130a-3p-mediated circRNA-mRNA ceRNA network using the miRanda database. This included 9 circRNAs (hsa_circ_0089378, hsa_circ_0083357, hsa_circ_0082824, hsa_circ_0068942, hsa_circ_0057576, hsa_circ_0054537, hsa_circ_0051172, hsa_circ_0032970, and hsa_circ_0006323) and 1 mRNA (transient receptor potential cation channel subfamily M member 3 [TRPM3]). We have shown that 9 circRNAs promote TRPM3 expression by inhibiting hsa-miR-130a-3p in CAD patients.

Association of admission serum calcium levels and in-hospital mortality in patients with acute ST-elevated myocardial infarction: an eight-year, single-center study in China.

Objective The relationship between admission serum calcium levels and in-hospital mortality in patients with acute ST-segment elevation myocardial infarction (STEMI) has not been well definitively explored. The objective was to assess the predictive value of serum calcium levels on in-hospital mortality in STEMI patients. Methods From 2003 to 2010, 1431 consecutive STEMI patients admitted to the First Affiliated Hospital of Nanjing Medical University were enrolled in the present study. Patients were stratified according to quartiles of serum calcium from the blood samples collected in the emergency room after admission. Between the aforementioned groups,the baseline characteristics, in-hospital management, and in-hospital mortality were analyzed. The association of serum calcium level with in-hospital mortality was calculated by a multivariable Cox regression analysis. Results Among 1431 included patients, 79% were male and the median age was 65 years (range, 55–74). Patients in the lower quartiles of serum calcium, as compared to the upper quartiles of serum calcium, were older, had more cardiovascular risk factors, lower rate of emergency revascularization,and higher in-hospital mortality. According to univariate Cox proportional analysis, patients with lower serum calcium level (hazard ratio 0.267, 95% confidence interval 0.164–0.433, p<0.001) was associated with higher in-hospital mortality. The result of multivariable Cox proportional hazard regression analyses showed that the Killips class≥3 (HR = 2.192, p = 0.026), aspartate aminotransferase (HR = 1.001, p<0.001), neutrophil count (HR = 1.123, p<0.001), serum calcium level (HR = 0.255, p = 0.001), and emergency revascularization (HR = 0.122, p<0.001) were significantly and independently associated with in-hospital mortality in STEMI patients. Conclusions Serum calcium was an independent predictor for in-hospital mortality in patients with STEMI. This widely available serum biochemical index may be incorporated into the current established risk stratification model of STEMI patients. Further studies are required to determine the actual mechanism and whether patients with hypocalcaemia could benefit from calcium supplement.