New potential modulators of CYP4F2 enzyme activity in angina pectoris: hsa-miR-24-3p and hsa-miR-34a-5p.

Purpose: To find an association of relative expression of hsa-miR-24-3p and hsa-miR-34a-5p molecules and CYP4F2 enzyme activity in blood plasma of stable angina pectoris (AP) patients'.Materials and Methods: MiRNA gene expression analysis was performed on total RNA extracted from blood plasma, using quantitative real-time polymerase chain reaction. CYP4F2 enzyme levels were determined using commercial ELISA kit. In total, 32 AP and 15 control samples were examined.Results: The relative expression of hsa-miR-24-3p and hsa-miR-34a-5p was upregulated by 4.4 (p = 0.0001) and 3.8 (p = 0.005) -fold in AP patient's blood plasma compared to control subjects. CYP4F2 enzyme level in blood plasma were 2.1 (p = 0.001) times lower in AP patients. Circulating hsa-miR-24-3p was negatively associated with CYP4F2 enzyme level (Spearman correlation coefficient rank r= -0.32; p = 0.03). Moreover, patients that were taking atorvastatin, had 1.5 (p = 0.04) times higher hsa-miR-24-3p expression in blood plasma.Conclusions. Our data suggest that hsa-miR-24-3p might have an effect on CYP4F2 activity during atherosclerosis.

Deoxyribonucleic Acid Repair Activity Is Associated with Healed Coronary Plaque Rupture by Optical Coherence Tomography.

Deoxyribonucleic acid (DNA) damage and repair signaling cascades are related to the development of atherosclerosis. Pathological studies have demonstrated that healed coronary plaque rupture (HCPR) contributes to plaque progression and predisposes to sudden ischemic cardiac death. The objective of this study is to investigate the relationship between HCPR detected by optical coherence tomography (OCT) and DNA ligase. Forty-two patients with both OCT and DNA ligase were prospectively enrolled. The population included patients with stable angina pectoris (SA) and non-ST-elevation myocardial infarction (NSTEMI). It was found that the prevalence of HCPR was greater in subjects with higher DNA ligase activity (correlation coefficient 0.36, p = 0.019). The presence of HCPR in patients with NSTEMI was greater than in patients with SA per OCT analysis; however, there was no statistical difference in this limited population (22.53% versus 12.83%, respectively, p = 0.116). DNA repair activity by DNA ligase was associated with HCPR in advanced coronary artery plaque by OCT.

DNA Damage and Repair in Patients With Coronary Artery Disease: Correlation With Plaque Morphology Using Optical Coherence Tomography (DECODE Study).

OBJECTIVE: The aim of this study was to examine DNA ligase activity and expression of DNA damage response pathway (DDR) genes in patients with stable angina (SA) and non-ST elevation myocardial infarction (NSTEMI) and determine whether they correlate with plaque morphology. BACKGROUND: Patients with coronary artery disease (CAD) have evidence of deoxyribonucleic acid (DNA) damage in peripheral blood mononuclear cells (PBMCs). It is unclear whether this represents excess damage or defective DNA repair activity. METHODS: DNA ligase activity and the expression of 22 DDR genes were measured in PBMCs of patients (both SA (n = 47) and NSTEMI (n = 42)) and in age and gender-matched controls (n = 35). Target lesion anatomical assessment was undertaken with frequency domain optical coherent tomography. RESULTS: DNA ligase activity was different across the three groups of patients (control = 119 ±â€¯53, NSTEMI = 115.6 ±â€¯85.1, SA = 81 ±â€¯55.7 units/g of nuclear protein; ANOVA p = 0.023). Pair wise comparison demonstrated that this significance is due to differences between the control and SA patients (p = 0.046). Genes involved in double strand break repair and nucleotide excision repair pathways were differentially expressed in patients with SA and NSTEMI. In SA patients, fibrocalcific plaques were strongly associated with GTSE1, DDB1, MLH3 and ERCC1 expression. By contrast, in NSTEMI patients the strongest association was observed between fibrous plaques and ATM and XPA expression. CONCLUSION: PBMCs from patients with CAD exhibit differences in DNA ligase activity and expression of DDR genes. Expression levels of certain DDR genes are strongly associated with plaque morphology and may play a role in plaque development and progression. Trial Registration Number URL: www.Clinicaltrials.gov; NCT02335086.

The effect of Danshen extract on lipoprotein-associated phospholipase A2 levels in patients with stable angina pectoris: study protocol for a randomized controlled trial - the DOLPHIN study.

BACKGROUND: Lipoprotein-associated phospholipase A2 (Lp-PLA2), a biomarker of oxidation and inflammation, has been associated with increased coronary artery disease risk. To date, very few studies have examined the Chinese herbal drug Danshen or its extract on Lp-PLA2 in patients with stable angina pectoris. In this study, we aim to investigate the effect of Danshen extract on Lp-PLA2 level in patients with stable angina. METHODS/DESIGN: This is a randomized, single-blind, placebo-controlled, adaptive clinical trial. A total of 156 patients meeting the eligibility criteria will be randomly assigned to either the Danshen extract (DanshenDuofensuanyan injection and Danshen drop spill) group or the placebo group in a 1:1 ratio. Participants will then undergo treatment with DanshenDuofensuanyan injection or placebo (glucose) during hospitalization, followed by open-label Danshen drop spill (30 pills/day) in Danshen extract group for 60 days after discharge. Because this is an adaptive trial, two interim analyses are prospectively planned. These will be performed after one-third and two-thirds of the patients, respectively, have completed the trial. On the basis of the results of these interim analyses, a data monitoring committee will determine how to modify aspects of the study without undermining the validity and integrity of the trial. The primary outcome measure is the serum level of Lp-PLA2 in the Danshen extract group and the placebo group. The secondary outcomes include the proportion of patients who show a clinically significant change, which is defined as at least a 20-point improvement in angina frequency score on the Seattle Angina Questionnaire and the carotid intima-media thickness, which will be measured using ultrasound. Other secondary efficacy and safety outcomes will also be assessed. DISCUSSION: This study will provide evidence that Danshen extract is beneficial for stable angina and may establish a possible mechanism of Danshen treatment effects on cardiovascular disease. This study may also validate an objective blood test (LP-PLA2 level) for assessing the effectiveness of Danshen therapy in patients with stable angina pectoris. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02870764 . Registered on 13 August 2016.

Methylenetetrahydrofolate Dehydrogenase 1 Polymorphisms Modify the Associations of Plasma Glycine and Serine With Risk of Acute Myocardial Infarction in Patients With Stable Angina Pectoris in WENBIT (Western Norway B Vitamin Intervention Trial).

BACKGROUND: Serine and glycine interconversion and methylenetetrahydrofolate dehydrogenase 1 (MTHFD1)-mediated 1-carbon transfer are the major sources of methyl groups for 1-carbon metabolism. Recently, plasma glycine and a common polymorphism in MTHFD1 have been associated with risk of acute myocardial infarction (AMI). It is, therefore, of interest to explore if these 2 pathways interact in relation to AMI. METHODS AND RESULTS: A total of 2571 participants in the WENBIT (Western Norway B Vitamin Intervention Trial) undergoing coronary angiography for stable angina pectoris were studied. Associations of plasma serine and glycine concentrations with risk of AMI across 2 common and functional MTHFD1 polymorphisms (rs2236225 and rs1076991) were explored in Cox regression models. During a median follow-up of 4.7 years, 212 patients (8.2%) experienced an AMI. In age- and sex-adjusted analyses, plasma glycine (P<0.01), but not serine (P=0.52), showed an overall association with AMI. However, interactions of MTHFD1 rs2236225 polymorphism with both plasma serine and glycine were observed (Pinteraction=0.03 for both). Low plasma serine and glycine were associated with an increased risk of AMI among patients carrying the rs2236225 minor A allele. Similarly, low plasma glycine showed stronger risk relationship with AMI in the rs1076991 CC genotype carriers but weaker associations in patients carrying the minor T allele (Pinteraction=0.02). CONCLUSIONS: Our results showed that 2 common and functional polymorphisms in the MTHFD1 gene modulate the risk associations of plasma serine and glycine with AMI. These findings emphasize the possible role of the MTHFD1 in regulating serine and glycine metabolism in relation to atherosclerotic complications. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique Identifier: NCT00354081.

Local Matrix Metalloproteinase 9 Level Determines Early Clinical Presentation of ST-Segment-Elevation Myocardial Infarction.

OBJECTIVE: Early clinical presentation of ST-segment-elevation myocardial infarction (STEMI) and non-ST-segment-elevation myocardial infarction affects patient management. Although local inflammatory activities are involved in the onset of MI, little is known about their impact on early clinical presentation. This study aimed to investigate whether local inflammatory activities affect early clinical presentation. APPROACH AND RESULTS: This study comprised 94 and 17 patients with MI (STEMI, 69; non-STEMI, 25) and stable angina pectoris, respectively. We simultaneously investigated the culprit lesion morphologies using optical coherence tomography and inflammatory activities assessed by shedding matrix metalloproteinase 9 (MMP-9) and myeloperoxidase into the coronary circulation before and after stenting. Prevalence of plaque rupture, thin-cap fibroatheroma, and lipid arc or macrophage count was higher in patients with STEMI and non-STEMI than in those with stable angina pectoris. Red thrombus was frequently observed in STEMI compared with others. Local MMP-9 levels were significantly higher than systemic levels (systemic, 42.0 [27.9-73.2] ng/mL versus prestent local, 69.1 [32.2-152.3] ng/mL versus poststent local, 68.0 [35.6-133.3] ng/mL; P<0.01). Poststent local MMP-9 level was significantly elevated in patients with STEMI (STEMI, 109.9 [54.5-197.8] ng/mL versus non-STEMI: 52.9 [33.0-79.5] ng/mL; stable angina pectoris, 28.3 [14.2-40.0] ng/mL; P<0.01), whereas no difference was observed in the myeloperoxidase level. Poststent local MMP-9 and the presence of red thrombus are the independent determinants for STEMI in multivariate analysis. CONCLUSIONS: Local MMP-9 level could determine the early clinical presentation in patients with MI. Local inflammatory activity for atherosclerosis needs increased attention.

Papel de la leptina sérica en la gravedad de la enfermedad coronaria en pacientes con angina estable / Role of serum leptin in the severity of coronary artery disease in patients with stable angina

Fundamentos y objetivo: La leptina es una hormona plasmática que ha sido relacionada con la homeostasis cardiovascular y la aterosclerosis, pero no existen datos concluyentes sobre su asociación con la patogénesis de la enfermedad coronaria. El objetivo de este estudio fue evaluar el valor de la leptina sérica en pacientes con angina estable y su relación con la gravedad de la enfermedad coronaria. Pacientes y método: Se incluyeron 204 pacientes, 152 con angina estable (grupo con enfermedad coronaria) y 52 sin enfermedad coronaria, excluida por tomografía computarizada cardíaca (grupo control). El grupo con enfermedad coronaria fue dividido en 2 subgrupos atendiendo a la gravedad de la afectación (enfermedad monovaso o multivaso, 46 y 106 pacientes respectivamente). Los niveles de leptina sérica fueron determinados mediante Enzyme-Linked Inmunosorbent Assay. Resultados: Los niveles de leptina fueron significativamente superiores en los pacientes con enfermedad multivaso y se asociaron de forma independiente con una mayor gravedad de la enfermedad coronaria en comparación con los controles (OR 1,14; IC95% 1,03-1,27; p = 0,014) y con pacientes con enfermedad monovaso (OR 1,12; IC95% 1,01-1,25; p = 0,036). Se testó el valor diagnóstico de la leptina sérica para el diagnóstico enfermedad multivaso, obteniendo un área bajo la curva en la curva Receiver Operating Characteristic de 0,6764 (IC95% 0,5765-0,7657). Conclusiones: La leptina sérica se asoció en pacientes con angina estable con la mayor gravedad de la enfermedad coronaria, mostrando su implicación en el desarrollo de la enfermedad coronaria y como futuro objetivo terapéutico (AU)

Background and objectives: Leptin is a plasmatic peptide hormone that has been related to cardiovascular homeostasis and atherosclerosis but much is still unknown about its relationship with coronary artery disease. The aim of this study was to evaluate the value of serum leptin in patients with stable angina and its relationship with the severity of coronary disease. Patients and methods: 204 patients, 152 with stable angina (coronary artery disease group) and 52 without coronary disease excluded by cardiac computerized tomography (control group) were included. The coronary artery disease group was divided into 2 subgroups according to severity of coronary disease (single or multivessel disease, 46 and 106 patients, respectively). Serum leptin levels were determined by Enzyme-Linked InmunoSorbent Assay. Results: Leptin levels were significantly higher in patients with multivessel disease and were independently associated with a greater severity of coronary artery disease when compared with controls (OR 1.14; 95%CI: 1.03-1.27; p = 0.014) and with patients with single vessel disease (OR 1.12; 95%CI: 1.01-1.25; p = 0.036). Serum leptin was tested as a diagnostic marker of multivessel disease with an area under the curve obtained from Receiver Operating Characteristics of 0.6764 (95%CI 0.5765-0.7657). Conclusions: Serum leptin levels were associated in patients with stable angina with the severity of coronary artery disease, suggesting its value in the development of coronary disease and as a future therapeutic target (AU)

B vitamin treatments modify the risk of myocardial infarction associated with a MTHFD1 polymorphism in patients with stable angina pectoris.

BACKGROUND: Methylenetetrahydrofolate dehydrogenase (MTHFD1) catalyzes three sequential reactions that metabolize derivatives of tetrahydrofolate (THF) in folate-dependent one-carbon metabolism. Impaired MTHFD1 flux has been linked to disturbed lipid metabolism and oxidative stress. However, limited information is available on its relation to the development of atherothrombotic cardiovascular disease. METHODS AND RESULTS: We explored the association between a MTHFD1 polymorphism (rs1076991 C > T) and acute myocardial infarction (AMI), and potential effect modifications by folic acid/B12 and/or vitamin B6 treatment in suspected stable angina pectoris patients (n = 2381) participating in the randomized Western Norway B Vitamin Intervention Trial (WENBIT). During the median follow-up of 4.9 years 204 participants (8.6%) suffered an AMI. After adjusting for established CVD risk factors, the MTHFD1 polymorphism was significantly associated with AMI (HR: 1.49; 95% CI, 1.23-1.81). A similar association was observed among patients allocated to treatment with vitamin B6 alone (HR: 1.53; 95% CI, 1.01-2.31), and an even stronger relationship was seen in patients treated with both vitamin B6 and folic acid/B12 (HR: 2.35; 95% CI, 1.55-3.57). However, no risk association between the MTHFD1 polymorphism and AMI was seen in patients treated with placebo (HR: 1.29; 95% CI, 0.86-1.93) or folic acid/B12 (1.17; 95% CI, 0.83-1.65). CONCLUSION: A common and functional MTHFD1 polymorphism is associated with increased risk of AMI, although the risk seems to be dependent on specific B vitamin treatment. Further studies are warranted to elucidate the possible mechanisms, also in order to explore potential effect modifications by nutritional factors.

Atorvastatin treatment increases plasma bilirubin but not HMOX1 expression in stable angina patients.

BACKGROUND: In vitro and animal studies indicate that statins increase heme oxygenase-1 gene (HMOX1) expression, which then, presumably, increases plasma bilirubin concentration. However, clinical confirmation that statins concomitantly increase HMOX1 expression and plasma bilirubin concentration is lacking. We hypothesized that in patients with stable angina atorvastatin therapy (20 mg/day for 10 weeks) concomitantly increases total bilirubin concentration and HMOX1 expression, as assessed non-invasively by plasma analysis. METHODS: In 44 patients with stable angina plasma concentrations of total bilirubin, HMOX1 mRNA and HMOX1 protein were measured before and after the statin treatment, as well as plasma concentrations of oxidized low-density lipoprotein (OxLDL), malondialdehyde (MDA), monocyte chemoattractant protein (MCP-1) and C-reactive protein (CRP). RESULTS: Atorvastatin treatment increased total bilirubin concentration (median 6.95 µmol/L vs. 8.55, + 23.02%; p < 0.001), but did not change plasma HMOX1 mRNA and HMOX1 protein concentrations. Plasma concentrations of OxLDL (- 31.85%, p < 0.001), MCP-1 (- 16.20%, p = 0.020) and CRP (- 7.32%, p = 0.010) were decreased but MDA was not decreased (15.32%, p = 0.107). Within subjects, increment of plasma bilirubin concentration did not correlate with the changes in HMOX1 mRNA and protein concentrations, but correlated with low-density lipoprotein cholesterol decrement (r = - 0.374, p = 0.012). Bilirubin increment did not correlate with the changes in oxidative and inflammatory markers. CONCLUSION: Our prospective observational trial finally confirms that atorvastatin (20 mg/day for 10 weeks) increases plasma total bilirubin concentration. However, it seems that this effect is HMOX1-independent.

Characterization of interleukin-33 and matrix metalloproteinase-28 in serum and their association with disease severity in patients with coronary heart disease.

OBJECTIVE: To investigate serum levels of interleukin (IL)-33 and matrix metalloproteinase-28 (MMP-28) in patients with coronary heart disease (CHD) and to evaluate their association with disease severity. METHODS: A total of 103 patients with CHD, including 27 cases of acute myocardial infarction (AMI), 33 cases of unstable angina pectoris (UAP) and 43 cases of stable angina pectoris were enrolled to detect serum levels of IL-33 and MMP-28 by enzyme-linked immunosorbent assays. Forty volunteers without CHD served as the control group. RESULTS: Compared with stable angina pectoris and control groups, serum levels of IL-33 were significantly lower (P<0.01) and serum concentrations of MMP-28 were higher (P<0.05) in AMI and UAP groups. Serum levels of IL-33 in single-vessel, double-vessel and triple-vessel lesion groups were lower than that in the control group (P<0.05), and the differences among the three groups were not significant (P>0.05), whereas only levels of MMP-28 in double-vessel and triple-vessel lesion groups were higher than in the control group (P<0.05). Spearman's correlation analyses showed a negative correlation between serum levels of IL-33 and MMP-28 in AMI and UAP groups (r=-0.596, P<0.05 and r=-0.750, P<0.01). A binary logistic regression analysis showed that IL-33, low-density lipoprotein cholesterol, and MMP-28 may be independent predictors of the occurrence of acute coronary syndrome. CONCLUSION: A decreased level of IL-33 and an elevated concentration of MMP-28 were found in CHD patients and correlated with disease severity. IL-33 and MMP-28 may play important roles in the development of CHD or as markers of disease severity.

Correlation between the serum alkaline phosphatase level and the severity of coronary artery disease.

OBJECTIVES: The serum alkaline phosphatase (ALP) level has shown to be a prognostic factor in myocardial infarction and peripheral vascular disease by its promoting effect on vascular calcification. A few recent studies also showed that elevated ALP levels were associated with mortality and unfavorable prognosis in coronary artery disease (CAD). Herein, we aimed to investigate the correlation between serum ALP levels and the severity of CAD by assessing the Gensini score. MATERIALS AND METHODS: A total of 470 patients with stable angina pectoris were evaluated retrospectively.Upon admission, their ALP levels were measured with an automated analyzer by the enzymatic method, and the severity of CAD was documented for each patient according to their Gensini score. Patients with a Gensini score greater than 40 were defined to have an advanced CAD. Serum ALP levels higher than 129 mg/dl in men and higher than 104 mg/dl in women were defined as the elevated ALP groups. RESULTS: The mean ALP level was 97.3±56.4, ranging from 15 to 485 U/l with 66.0/82.5/106.0 U/l percentile values, and elevated ALP levels were obtained in 79 cases (16.8%). In 70% of the patients (n=329), advanced CAD was diagnosed. The mean Gensini score was 85.6±29.4 in the advanced CAD group and 12.8±15.8 in the remainder of the patients. The advanced CAD group included more men, patients with diabetes mellitus, hypertension, and a reduced left ventricular ejection fraction, and patients with lower levels of high-density lipoprotein cholesterol and higher levels of creatinine, red cell distribution width, and mean platelet volume. ALP levels (105.4±60.7 vs. 78.4±38.7 U/l, P<0.001) and the frequency of patients with elevated ALP levels (22 vs. 5.0%, P<0.001) were significantly higher in the advanced CAD group. Regression analysis showed a significant correlation between increased levels of serum ALP and advanced CAD in univariate (odds ratio 1.015, 95% confidence interval 1.008-1.1291, P<0.001) and multivariate analyses (odds ratio 1.013, 95% confidence interval 1.003-1.023, P=0.01). CONCLUSION: Elevated ALP levels are associated with higher Gensini scores and a more severe form of CAD.

Polyunsaturated omega-3 fatty acids reduce lipoprotein-associated phospholipase A(2) in patients with stable angina.

BACKGROUND AND AIMS: Increased consumption of omega-3 polyunsaturated fatty acids (PUFA) together with lifestyle measures and medications is recommended for the prevention of cardiovascular diseases. However, the exact mechanisms underlying observed benefits are not well defined. To this aim, we evaluated the effects of omega-3 PUFA in stable coronary artery disease (CAD) patients undergoing percutaneous coronary intervention (PCI) on lipoprotein associated phospholipase A2 (Lp-PLA2) mass and activity and their relation to oxidized low-density lipoproteins (oxy-LDL). METHODS AND RESULTS: In a prospective, double-blind, placebo-controlled, randomized study Lp-PLA2, oxy-LDL, myeloperoxidase and interleukin-6 were determined at baseline, 3-5 days and 30 days during administration of omega-3 PUFA 1 g/day (n = 30) or placebo (n = 24). Treatment with omega-3 PUFA resulted in reduction of Lp-PLA2 mass by 10.7%, activity by 9.3 (p = 0.026 for both) and oxy-LDL by 10.9% (p = 0.014) at 30 days, with no change in myeloperoxidase and interleukin-6. Compared with placebo, patients receiving omega-3 PUFA had lower Lp-PLA2 mass by 9.42%, activity by 9.2 (p = 0.041 for both) and oxy-LDL by 12.3% (p = 0.10) after one month, but not at 3-5 days. There were no correlations between Lp-PLA2 and both myeloperoxidase and oxy-LDL throughout the study. The multivariate model showed that only treatment with omega-3 PUFA and baseline myeloperoxidase levels were independent predictors of Lp-PLA2 mass changes at one month (R(2) = 0.37, P = 0.005). CONCLUSIONS: Administration of omega-3 PUFA can decrease Lp-PLA2 in patients with stable angina undergoing PCI. This novel effect may contribute to the benefits derived from omega-3 PUF.

Ischemic heart diseases in Egypt: role of xanthine oxidase system and ischemia-modified albumin.

It is known that xanthine oxidoreductase contributes significantly to ischemia/reperfusion injury by generating reactive oxygen species. Ischemia-modified albumin (IMA) is a biomarker of acute myocardial ischemia with high sensitivity but moderate specificity. Our study aims to evaluate the xanthine oxidase (XO) system and the IMA level in the serum of patients with ischemic heart disease, and their correlation with traditional cardiac markers. The study was conducted on 60 patients with ischemic heart disease and 22 healthy subjects (control group). Subjects were divided into three groups: group I (30 patients with ST-elevated myocardial infarction), group II (30 patients with chronic stable angina), and the control group (22 subjects). The patients and controls had laboratory tests performed including lipid profile, cardiac enzymes, XO, uric acid, and IMA. The serum levels of XO and IMA were significantly higher in group I (1.65 ± 0.29 U/ml and 0.58 ± 0.15 ABSU, respectively) than in group II (1.11 ± 0.20 U/ml and 0.29 ± 0.10 ABSU, respectively) and the control group (0.95 ± 0.16 U/ml and 0.24 ± 0.08 ABSU, respectively) (P < 0.001). There was a significant positive correlation between XO and IMA in group I. Also, there was significant positive correlation between XO or IMA and other cardiac markers, with the highest level of significance between IMA and creatine kinase (CK-MB). In group II only XO activity was significantly elevated in comparison with controls. These results confirm the role of XO enzyme in ischemic heart disease with involvement of IMA, at a detectable level, during the early necrotic phase.

Macrophage activation by heparanase is mediated by TLR-2 and TLR-4 and associates with plaque progression.

OBJECTIVE: Factors and mechanisms that activate macrophages in atherosclerotic plaques are incompletely understood. We examined the capacity of heparanase to activate macrophages. METHODS AND RESULTS: Highly purified heparanase was added to mouse peritoneal macrophages and macrophage-like J774 cells, and the levels of tumor necrosis factor-α, matrix metalloproteinase-9, interlukin-1, and monocyte chemotactic protein-1 were evaluated by ELISA. Gene expression was determined by RT-PCR. Cells collected from Toll-like receptor-2 and Toll-like receptor-4 knockout mice were evaluated similarly. Heparanase levels in the plasma of patients with acute myocardial infarction, stable angina, and healthy subjects were determined by ELISA. Immunohistochemistry was applied to detect the expression of heparanase in control specimens and specimens of patients with stable angina or acute myocardial infarction. Addition or overexpression of heparanase variants resulted in marked increase in tumor necrosis factor-α, matrix metalloproteinase-9, interlukin-1, and monocyte chemotactic protein-1 levels. Mouse peritoneal macrophages harvested from Toll-like receptor-2 or Toll-like receptor-4 knockout mice were not activated by heparanase. Plasma heparanase level was higher in patients with acute myocardial infarction, compared with patients with stable angina and healthy subjects. Pathologic coronary specimens obtained from vulnerable plaques showed increased heparanase staining compared with specimens of stable plaque and controls. CONCLUSIONS: Heparanase activates macrophages, resulting in marked induction of cytokine expression associated with plaque progression toward vulnerability.

Phosphoglucomutase activity as a novel biomarker in patients with acute myocardial infarction.

BACKGROUND: Phosphoglucomutase (PGM), a key enzyme in cellular glucose utilization and energy homeostasis, has been reported to show a relationship with oxidative stress. However, the clinical importance of PGM activity has not been investigated in patients with ischemic heart disease (IHD). The aim of the present pilot study was to clarify whether PGM activity has potential as a cardiovascular risk predictor in patients with IHD. METHODS AND RESULTS: The levels of serum PGM activity in 237 patients with IHD (63 patients with acute myocardial infarction (AMI) and 174 patients with stable effort angina pectoris (EAP)) were evaluated. PGM activity was compared with levels of various myocardial, thrombosis, and inflammatory biomarkers on admission. PGM activity in the AMI group was significantly increased relative to that in the EAP group on admission (AMI, 55.5 µmol·min(-1)·L(-1) (U/L); EAP, 14.4 U/L (P<0.001)), and was observed to increase in parallel with well-established myocardial markers (P<0.001). Moreover, PGM activity and the lipid, thrombosis, and inflammatory biomarkers in the AMI group were higher than those in the EAP group. CONCLUSIONS: PGM activity increased with levels of myocardial, thrombosis, and inflammatory biomarkers in patients with AMI, and might be useful in diagnostic applications during the acute phase in patients with AMI.

Expression of ADAMTS-2, -3, -13, and -14 in culprit coronary lesions in patients with acute myocardial infarction or stable angina.

ADAMTS (a disintegrin and metalloproteinase with thrombospondin type 1 motifs) proteases are emerging as key participants in the pathogenesis of vascular diseases. We studied the expression of ADAMTS-2, -3, -4 and -14 in the culprit plaques from patients presenting with acute myocardial infarction (AMI) versus stable angina. Tissue samples were gathered from 52 patients with AMI (n = 35) or stable angina (n = 17) who underwent directional coronary atherectomy. The specimens were stained with hematoxylin-eosin and analyzed immunohistochemically using antibodies specific to ADAMTS-2, -3, -13 and -14, and markers for endothelial cells, macrophages, and smooth muscle cells. Baseline characteristics of the groups were mostly similar. The proportion of smooth muscle α-actin-immunopositive area was smaller in the AMI group than in the stable angina group, but the areas immunopositive for CD31 or CD68 were higher in the AMI group. The relative areas immunopositive for ADAMTS-2, -3, and -13 in AMI were significantly larger than those in stable angina. However, the proportion of areas immunopositive for ADAMTS-14 did not differ between the two groups. Areas that stained for ADAMTS-2, -3, -13, and -14 largely overlapped with those positive for CD31 or CD68. The areas immunopositive for ADAMTS proteases were significantly correlated with CD31- or CD68-immunostained areas. In conclusions, ADAMTS-2, -3, and -13 expression, but not that of ADAMTS-14, are increased in plaques causing AMI compared those associated with stable angina. These results support a role for these enzymes in the pathogenesis of AMI.

Association of lipoprotein-associated phospholipase A2 with characteristics of vulnerable coronary atherosclerotic plaques.

PURPOSE: Lipoprotein-associated phospholipase A2 (Lp-PLA2) is an inflammatory enzyme expressed in atherosclerotic plaques. We investigated the association of circulating Lp-PLA2 with characteristics of vulnerable coronary atherosclerotic plaques. MATERIALS AND METHODS: We recruited 113 patients with either unstable angina (UA, n=59) and stable angina (SA, n=54) by coronary angiography. Thirty-six healthy subjects served as controls. Intravascular ultrasound (IVUS) was used to evaluate the characteristics of coronary atherosclerotic plaque, and serum Lp-PLA2 concentration was measured as well. RESULTS: Lp-PLA2 concentration was significantly higher in both UA and SA patients [(396±36) µg/L and (321±39) µg/L, respectively] compared with the controls [(127 ± 49) µg/L, p<0.01], and higher in UA than SA group. IVUS findings showed that remodeling index (RI) (0.91 ± 0.15 vs. 0.85 ± 0.11, p=0.005) and eccentricity index (EI) (0.73 ± 0.16 vs. 0.65 ± 0.22, p=0.039) were larger in UA than in SA group, and fibrous caps were thicker in SA than UA group [(0.91 ± 0.23) mm vs. (0.63 ± 0.21) mm, p=0.032]. Moreover, Lp-PLA2 correlated positively with EI (r=0.439, p<0.01) and RI (r=0.592, p<0.05) in UA group. There was an inverse relationship between Lp-PLA2 and fibrous cap thickness in both UA (r=-0.587, p<0.001) and SA (r=-0.318, p<0.05) groups. The independent risk factors in UA group were Lp-PLA2 (OR=1.055, 95% CI: 1.03-1.08, p=0.013), LDL-cholesterol (OR=0.032, 95% CI: 0.00-0.05, p=0.041) and fibrous cap thickness (OR=0.008, 95% CI: 0.00-0.45, p=0.019). Lp-PLA2 was strongly associated with both EI and fibrous cap thickness in both groups. CONCLUSION: Serum level of Lp-PLA2 is associated with both eccentricity index and fibrous cap thickness in both UA and SA groups. Elevated levels of circulating Lp-PLA2 might to be a strong risk factor and more serious for unstable angina than stable angina.

A randomized study assessing the effects of pretreatment with cilostazol on periprocedural myonecrosis after percutaneous coronary intervention.

PURPOSE: It is unknown whether cilostazol pretreatment reduces postprocedural myonecrosis (PPMN). Cilostazol pretreatment reduces PPMN after percutaneous coronary intervention (PCI). MATERIALS AND METHODS: A total of 120 patients with stable angina scheduled for elective PCI were randomly assigned to a 7-day pretreatment with Cilostazol (200 mg/day) or to a control group. Creatine kinase-MB (CK-MB) and cardiac troponin I (cTnI) levels were measured at baseline and at 6 and 24 hours after PCI. The primary end-point was the occurrence of PPMN, defined as any CK-MB elevation above the upper normal limit (UNL). Aspirin and clopidogrel were co-administered for 7 days before PCI, and resistance to these agents was then assayed using the VerifyNow System. RESULTS: There was no difference in baseline characteristics between the final analyzable cilostazol (n=54) and the control group (n=56). Despite a significantly greater % inhibition of clopidogrel in the cilostazol group (39±23% versus 25±22%, p=0.003), the incidence of PPMN was similar between the cilostazol group (24%) and the control group (25%, p=1.000). The rate of CK-MB elevation at ≥3 times UNL was also similar between the two groups (6% versus 5%, p=0.583). The incidence of cTnI increase over the UNL or to 3 times the UNL was not different between the two groups. There was no significant difference in terms of the rate of adverse events during follow- up, although the cilostazol group showed a tendency to have a slightly higher incidence of entry site hematoma. CONCLUSION: This trial demonstrated that adjunctive cilostazol pretreatment might not significantly reduce PPMN after elective PCI in patients with stable angina.