Quantitative proteomics reveals the regulatory networks of circular RNA BTBD7_hsa_circ_0000563 in human coronary artery.

BACKGROUND: BTBD7_hsa_circ_0000563, which is located on chromosome 14, contains conserved binding sites with miR-155/130a and RNA-binding proteins according to bioinformatic prediction. We investigated the association of BTBD7_hsa_circ_0000563 expression in coronary artery segments with atherosclerotic stenosis and identified the proteome-wide BTBD7_hsa_circ_0000563-regulated proteins in human coronary artery. METHODS: The atherosclerotic grade and extent in coronary artery segments were determined by hematoxylin and eosin staining. BTBD7_hsa_circ_0000563 expression in eight coronary artery segments from one patient was quantified by RT-qPCR assay. A proteomic approach was adopted to reveal significant differences in protein expression between among four groups differing in their BTBD7_hsa_circ_0000563 expression levels. RESULTS: The RT-qPCR assay revealed that coronary artery segments with severe atherosclerotic stenosis had significantly low BTBD7_hsa_circ_0000563 levels. The proteomic analysis identified 49 differentially expressed proteins among the segment groups with different BTBD7_hsa_circ_0000563 expression levels, of which 10 were downregulated and 39 were upregulated with increases in the BTBD7_hsa_circ_0000563 level. The 10 downregulated proteins were P61626 (LYSC_HUMAN), P02760 (AMBP_HUMAN), Q02985 (FHR3_HUMAN), P01701 (LV151_HUMAN), P06312(KV401_HUMAN), P01624 (KV315_HUMAN), P13671 (CO6_HUMAN), P01700(LV147_HUMAN), Q9Y287(ITM2B_HUMAN), and A0A075B6I0 (LV861_HUMAN). The top 10 upregulated proteins were Q92552 (RT27_HUMAN), Q9UJY1(HSPB8_HUMAN), Q9Y235(ABEC2_HUMAN), P19022 (CADH2_HUMAN), O43837(IDH3B_HUMAN), Q9H479(FN3K_HUMAN), Q9UM22(EPDR1_HUMAN), P48681(NEST_HUMAN), Q9NRP0(OSTC_HUMAN), and Q15628(TRADD_HUMAN). CONCLUSION: BTBD7_hsa_circ_0000563 is involved in the atherosclerotic changes in human coronary artery segments. Verification, mechanistic, and function studies are needed to confirm whether patients with coronary artery disease would benefit from such personalized medicine in the future.

Analysis on the polymorphisms of site RS4977574, and RS1333045 in region 9p21 and the susceptibility of coronary heart disease in Chinese population.

BACKGROUND: Rs4977574 (A > G) and Rs1333045 (C > T) are both single nucleotide polymorphisms (SNPs) related with coronary artery disease, locating on chromosome 9p21.3. The study aimed to identify the correlation between rs4977574 and rs1333045 polymorphism genotypes and coronary heart disease (CHD) in a Chinese population. METHODS: Blood samples were collected from 855 subjects. A case-control study was used in this experiment, and 598 cases in the CHD group and 257 subjects in the control group were enrolled. Genotyping was identified by the Agena MassARRAY system. Statistical analysis was conducted by SPSS (Ver 16.0) and plink (Ver. 1.07, Shaun Purcell). Haplotype analysis was performed using Haploview software. RESULTS: Association analysis by plink indicated a significant difference in the allele distribution for single nucleotide polymorphisms between cases and controls (rs4977574 P = 0.003, rs1333045 P = 0.035). Fisher's exact test by plink proved that allele G may be associated with a higher risk of CHD (P = 0.003, odds ratio (OR) = 1.371) and the T allele was likely to reduce the risk of coronary events (P = 0.035, OR = 0.798). The serum levels of apolipoprotein A (ApoA) were higher in subjects with the AG + AA genotype of rs4977574 compared to those with the GG genotype (P = 0.028). In the dominant model of rs1333045, the levels of ApoA were higher and LDL levels were lower in the TC + TT genotype than in the CC genotype. CONCLUSIONS: The present study examined the association between the 9p21 chromosome rs4977574 and rs1333045 polymorphism genotypes and CHD in a population of Chinese patients. The G allele of rs4977574 and the C allele of rs1333045 are the susceptibility sites of CHD.

Circular RNA profile in coronary artery disease.

Circular RNAs (circRNAs) are potential biomarkers and therapeutic targets of coronary artery disease due to their high stability, covalently closed structure. And implied roles in gene regulation. The aim of this study was to identify and characterize circRNAs from human coronary arteries. Epicardial coronary arteries were removed during the autopsy of an 81-year-old man who died from heart attack. The natural history and histological classification of atherosclerotic lesions in coronary artery segments were analyzed by hematoxylin and eosin staining, and their circRNA expression profiles were characterized by RNA sequencing. RNA sequencing identified 1259 annotated and 381 novel circRNAs. Combined with the results of histologic examination, intersection analysis identified 54 upregulated and 12 downregulated circRNAs, representing 4.0% of the total number. Coronary artery segments with or without severe atherosclerosis showed distinctly different circRNA profiles on the basis of hierarchical clustering. Our results suggest that these 66 circRNAs contribute to the pathology underlying coronary artery atherosclerosis and may serve as diagnostic or therapeutic targets in coronary artery disease.

DNA methylation of antisense noncoding RNA in the INK locus (ANRIL) is associated with coronary artery disease in a Chinese population.

To explore the association between methylation of antisense non-coding RNA in the INK4 locus (ANRIL) and coronary artery disease (CAD) development. Methylation levels of ANRIL in 100 subjects with CAD and 100 controls were quantitatively analyzed using Sequenom MassARRAY. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was used to identify novel pathways. Our analyses indicated that 7 to 8 CpG sites within the 2nd CpG island located upstream of ANRIL, also known as cyclin-dependent kinase inhibitor 2B - antisense 1 (CDKN2B-AS1), are hyper-methylated in CAD subjects compared to controls (p = 0.034). The 40th CpG site within the 2nd CpG island located upstream of CDKN2B-AS1 was methylated to a lesser extent in CAD subjects compared to controls (p = 0.045). Both Pearson and Spearman analyses indicated that methylation levels were significantly associated with total cholesterol (r = 0.204, p = 0.004), fasting high-density lipoprotein cholesterol (r = 0.165, p = 0.020), and fasting low-density lipoprotein cholesterol (r = 0.265, p = 0.000). KEGG pathway analysis revealed a significant enrichment of genes associated with the tumor necrosis factor (TNF) signaling pathway. Among them, CCAAT/enhancer binding protein (C/EBPß) was identified as a key transcription factor that promotes expression of CDKN2B-AS1 through promotor interaction. DNA methylation of the ANRIL promoter was significantly associated with CAD development in our study. Our analyses suggest that C/EBPß is a key transcription factor that promotes CDKN2B-AS1 expression by directly interacting with the gene promotor mediated by TNF signaling.

The association between peroxisome proliferator-activated receptor Δ rs3777744, rs3798343, and rs6922548 and coronary artery disease.

Objective: The aim of the present study is to investigate the association between the single nucleotide polymorphism (SNP) sites of peroxisome proliferator-activated receptor Δ (PPARD) and the risk of coronary artery disease (CAD). To this end, a prospective observational single-center study of the clinical data from 880 subjects in a Chinese population was conducted. Methods: A total of 880 subjects, including 609 CAD patients and 271 control subjects, were selected for the present study. All inpatients had 4 ml of venous blood drawn after 12 h of fasting, and then clinical tests were conducted to obtain the biochemical parameters. CAD patients and Controls were distinguished by coronary angiography. Statistical analysis was conducted with SPSS software (ver 16.0). Results: A significant association between the G-alleles of PPARD rs3777744 and rs3798343 and a decreased risk for CAD was found. Moreover, we found an interaction between high fasting high-density lipoprotein cholesterol (HDL-C) serum levels, low serum glucose levels and their genotypes, ultimately decreasing the risk of CAD. Haplotype analysis was conducted on the three SNP sites, rs3777744 and rs3798343 to form a block [r2 = 0.79, D' = 0.99). The A-C haplotypes were associated with an increased risk of CAD (odds ratio (OR), 95% confidence interval (CI): 1.321 (1.060-1.647), P=0.013], and the G-G haplotypes were associated with a decreased risk [OR, 95% CI: 0.714 (0.567-0.849), P=0.004]. Conclusions: Our study indicates a significant association between the G-alleles of PPARD rs3777744 and rs3798343 and a decreased CAD risk. In addition, genotypes interact with high serum HDL-C levels and low serum glucose levels, resulting in decreased prevalence of CAD.

Age-sex distribution of patients with high-sensitivity troponin T levels below the 99th percentile.

BACKGROUND: Recently, very low concentrations of high-sensitivity cardiac troponin T (hs-cTnT), below the 99th percentile, have been used to immediately exclude acute myocardial infarction in certain patients without taking their age and sex into consideration. RESULTS: The hs-cTnT values below the 99th percentile (≤ 14 ng/L) were higher in men (p = 0.000) and significantly increased with age (p = 0.000) among both men and women. In addition, hs-cTnT was positively associated with age (r = 0.459, p = 0.000), myoglobin (r = 0.392, p = 0.000), and creatine kinase-MB (r = 0.133, p = 0.000). Moreover, males were younger (p = 0.001) and had higher myoglobin (p = 0.000) and creatine kinase-MB (p = 0.000) concentrations than females. MATERIALS AND METHODS: A total of 5585 consecutive subjects who presented with non-traumatic chest pain/discomfort to the inpatient, outpatient, or emergency department and who underwent high-sensitivity troponin T, myoglobin and creatine kinase-MB testing at presentation, with hs-cTnT below the 99thpercentile (≤ 14 ng/L), were eligible for enrollment. CONCLUSIONS: We suggest that patients' age, sex and levels of myocardial injury biomarkers should be taken into consideration when ruling out acute myocardial infarction and/or adverse prognostic implications in patients who have very low hs-cTnT concentrations.

Coronary Artery Diameter is Inversely Associated with the Severity of Coronary Lesions in Patients Undergoing Coronary Angiography.

BACKGROUND: The diameters of the coronary arteries have been suggested to be a potential predictor of coronary artery disease (CAD). However, whether the diameters of the coronary arteries are associated with the coronary lesion severity on angiography has not been determined. METHODS: One hundred sixty-seven consecutive adult patients (109 men and 58 women) aged 31-84 years who underwent coronary angiography for suspected or known CAD were enrolled. The known catheter tip diameter was used as the calibration to measure the diameters of coronary arteries, and the severity of coronary lesions was evaluated with the vessel score and Gensini score. RESULTS: In patients with a higher vessel score and Gensini score, the diameters of the left main (LM), left anterior descending (LAD), left circumflex (LCX), and right coronary arteries (RCA) were smaller (all p<0.05) than those in patients with lower scores. Multiple linear regression analysis indicated that the average coronary artery diameter was significantly associated with the Gensini score (ß=-0.444, p<0.00001). Moreover, the diameters of the coronary arteries were potential predictors of CAD, with areas under the receiver operating characteristic curves of 0.268 for average diameter (95% confidence interval [CI]: 0.183-0.353, p<0.00001), 0.356 for the LM diameter (95% CI: 0.266-0.445, p=0.005), 0.214 for the LAD diameter (95% CI: 0.136-0.291, p<0.00001), 0.366 for the LCX diameter (95% CI: 0.271-0.461, p=0.009), and 0.346 for the RCA diameter (95% CI: 0.245-0.447, p=0.003). CONCLUSION: The diameters of coronary arteries are inversely associated with the severity of CAD.

Predictive Effects of Circulating miR-221, miR-130a and miR-155 for Coronary Heart Disease: A Multi-Ethnic Study in China.

BACKGROUND: Differences in microRNA (miRNA) profiles between patients with and without coronary heart disease (CHD)have not been fully determined. The purpose of the study was to evaluate in a multi-ethnic population in China the predictive value of miRNAs previously suggested to have a role in CHD. SUBJECT AND METHOD: 932 participants were included, and plasma samples obtained. A quantitative reverse-transcription PCR(RT-qPCR) assay was conducted to confirm the concentration of plasma miRNAs. Circulating levels of miRNAs were quantified using the 2-Δct method. The severity of coronary atherosclerosis was evaluated via Gensini Scores. RESULT: The circulating levels of the nine proposed miRNAs were not different among the five main ethnicities examined (all p > 0.05). The Spearman correlation analyses indicated that miR-221 and miR-130a were negatively associated with the severity of CHD as indicated by Gensini Scores (r = -0.106, p = 0.001;r = -0.073, p = 0.026). Results of the univariate analysis showed that lower circulating miR-221 (OR, 1.663; 95 % CI, 1.255-2.202, p = <0.001), miR-155 (OR, 1.520; 95 % CI, 1.132-2.042, p = 0.005), and miR-130a (OR, 1.943; 95% CI, 1.410-2.678, p = <0.001) were potential risk factors for CHD. Moreover, miR-130a (OR, 2.405; 95 % CI, 1.691-3.421, p = <0.001) remained independently associated with the risk of CHD after adjusting for potential confounding factors. The analysis of the possible positive/negative associations between miR-221, miR-155 and miR-130awere conducted. A positive association between miR-130a and miR-155 was found (SI = 1.60, SIM = 1.21 and AP = 0.22), and in these groups, the proportion of CHD attributable to the interaction between miR-130a and miR-155 was as high as 22 %. A negative interaction was found between miR-221 and miR-130a (SI = 0.68, SIM = 0.60 and AP = 0.27). CONCLUSION: Plasma levels of miR-221, miR-130a and miR-155 decreased in patients with CHD, and miR-130a may be an independent predictor for CHD.

Synergistic Effect of Lipoprotein-Associated Phospholipase A2 with Classical Risk Factors on Coronary Heart Disease: A Multi-Ethnic Study in China.

AIMS: We evaluated the synergistic effect of lipoprotein-associated phospholipase A2 (Lp-PLA2) in association with classical risk factors in predicting coronary heart disease (CHD) and demonstrated the diagnostic value of Lp-PLA2 for predicting coronary stenotic lesions in subjects with CHD. METHODS: Blood samples were acquired from 911 consecutive adult subjects (662 males and 249 females) from 11 ethnic groups. Lp-PLA2 plasma levels were detected using a commercially available turbidimetric immunoassay (TIA). CHD in patients was confirmed using coronary angiography, and the severity of coronary atherosclerosis was assessed using the Gensini scoring system. RESULTS: A binary logistic regression was performed to analyse the relationships between Lp-PLA2 and other risk factors. A multivariate logistic regression analysis revealed that Lp-PLA2 levels were significantly associated with CHD (OR, 1.882; 95% CI, 1.369-2.587, p=0.000).The area under the receiver operating characteristic curve for Lp-PLA2 was 0.589 (95%CI, 0.549-0.629, p=0.000).The synergism between Lp-PLA2 and other risk factors was also investigated. The proportion of CHD attributable to the interaction between Lp-PLA2 and age was as high as 64%. CONCLUSIONS: Lp-PLA2 levels in human plasma were positively associated with the severity of CHD, and there was a clear positive interaction between Lp-PLA2 and classical risk factors in predicting CHD.