Ewa Waszkiewicz

Green Tea Protection Against Age-Dependent Ethanol-Induced Oxidative Stress

Ethanol intoxication leads to oxidative stress, which may be additionally enhanced by aging. The aim of this study was to investigate the influence of green tea as a source of water-soluble antioxidants on the ability to prevent oxidative stress in aged rats sub-chronically intoxicated with ethanol. Two-, 12-, and 24-mo-old male Wistar rats were divided into 4 experimental groups: (1) control, (2) green tea, (3) ethanol, and (4) ethanol and green tea. Ethanol intoxication produced age-dependent decrease in the activity of serum superoxide dismutase, glutathione peroxidase, and reductase and in levels of glutathione (GSH), vitamins C, E, and A, and βcarotene. Changes in the serum antioxidative ability were accompanied by enhanced oxidative modification of lipid (increase in lipid hydroperoxides, malondiadehyde, and 4-hydroxynonenal levels) and protein (rise in carbonyl group levels). Green tea partially protected against changes in antioxidant enzymatic as well as nonenzymatic parameters produced by ethanol and enhanced by aging. Administration of green tea significantly protects cellular components such as lipids and proteins against oxidative modification. Results indicate that green tea effectively protects blood serum against oxidative stress produced by ethanol as well as aging.

Apelin: a novel marker for the patients with first ST-elevation myocardial infarction

To date, only animal studies have been concerned with apelin involvement in acute myocardial ischemia. The aim of this study was to investigate apelin measurements in low-risk patients with first ST-elevation myocardial infarction (STEMI) and to assess if apelin may feature as a marker of left ventricular (LV) injury and prognosis. In 78 consecutive patients (mean age 67 ± 11.5 years, 24 women) with first STEMI treated with primary percutaneous coronary intervention, plasma apelin-36 concentrations were measured twice: on admission and on the 5th day of hospitalization. Left ventricle ejection fraction (LVEF) was applied as marker of LV injury. Composite endpoint (CEP), which included death, stroke, and recurrent ischemic event, was assessed after 1 year follow-up. On the first day, median apelin-36 concentration was 2138.5 pg/ml and on the 5th day was significantly lower, 2008.3 pg/ml (P = 0.002). There were no significant differences found in apelin-36 concentrations between patients with normal and low LVEF. In both groups significant reductions were found in apelin-36 concentrations measured in 5-day intervals (P = 0.04 and P = 0.008, respectively). After a 1-year follow-up, only one patient died and 19 patients (24.3%) had reached CEP. No difference in baseline apelin-36 concentrations were found in the group of patients who reached CEP compared with those without CEP. However, in both groups concentrations significantly decreased after 5 days (P = 0.04 and P = 0.013, respectively). Apelin-36 concentrations are reduced in lowrisk first STEMI patients during the first days regardless of the degree of LV dysfunction and prognosis.

The value of apelin-36 and brain natriuretic peptide measurements in patients with first ST-elevation myocardial infarction☆

BACKGROUND We aimed to assess apelin-novel endogenous ligand for the angiotensin-like 1 receptor in patients with ST-elevation myocardial infarction (STEMI) and to compare its value with B-type natriuretic peptide (BNP). METHODS In 78 consecutive patients with first STEMI treated with primary PCI, plasma apelin-36 (RIA) and BNP (MEIA) concentrations were measured twice: on admission and on the fifth day of hospitalization. Left ventricle ejection fraction (LVEF) was assessed on admission and composite endpoint (CEP)-after 1 year follow-up. RESULTS During the 5-day interval median plasma BNP level significantly increased and median plasma apelin concentration significantly decreased. BNP, but not apelin, correlated with low LVEF (<50%). In ROC analysis only BNP measurements were diagnostic for low LVEF. In ANOVA test, in patients with CEP, a significant decrease in apelin (but not BNP) concentrations measured in 5-day interval was found. ROC analysis identified only second BNP measurement as significant to estimate adverse outcome 0.627 in the prediction of CEP (95% confidence interval=0.507-0.736). CONCLUSION Following STEMI there is a decrease of plasma apelin-36 concentration and an increase of plasma BNP concentration. BNP is better, than apelin diagnostic value for the detection of impaired LVEF. Both BNP and apelin have prognostic value, although both needs further evaluation.

Effect of interleukin 6 deficiency on the expression of Bcl-2 and Bax in the murine heart

Interleukin 6 (IL-6) is a pleiotropic cytokine that is highly expressed in response to ischemia and reperfusion. It has dichotomous roles in the heart, functioning both as an inflammatory mediator as well as a protective agent. The aim of this study was to evaluate the effect of IL-6 deficiency on the expression of apoptotic regulatory proteins under both baseline conditions and following induction of ischemia and reperfusion in the mouse heart. C57BL/6J IL-6-/-(TMKopf) (IL6KO) and C57BL/6J mice (WT) were subjected to 30 minutes of local reversible myocardial ischemia in vivo or a sham operation. The expression of Bcl-2, Bax and STAT3 in the heart was assessed by western blotting. Under both baseline conditions and following the sham operation, IL-6 deficiency was associated with reduced expression of Bcl-2 and Bax. The TUNEL-FITC, Evans blue and tetrazolium chloride staining of the hearts following ischemia and reperfusion revealed similar injury in operated IL6KO and WT animals. There was increased STAT3 phosphorylation in operated mice regardless of the genotype. Bcl-2 and Bax expression was also comparable between the mouse strains following ischemia and reperfusion. In summary, these results indicated that IL-6 deficiency affected the basal expression of apoptotic regulators, but this did not profoundly alter the extent of reperfusion injury or apoptosis in the mouse heart following ischemia and reperfusion.

Enhanced IL-6 trans-signaling in pulmonary arterial hypertension and its potential role in disease-related systemic damage.

BACKGROUND The role of IL-6 in pulmonary arterial hypertension (PAH) has been reported but the prevalence of soluble receptors for IL-6: sIL-6R and sgp130 and its potential role in PAH have not been studied.Our aim was to examine the IL-6 together with the soluble receptors and to assess its relationship with clinical status of PAH patients as well as to assess its potential prognostic significance. METHODS Serum concentrations of IL-6, sIL-6R and sgp130 were quantified by ELISA in 26 patients with PAH and 27 healthy controls and related to functional and biochemical parameters and clinical outcome in PAH group. The PAH patients were followed up for 1 year, noting the end point of clinical deterioration (WHO class change, the need for escalation of therapy) or death. RESULTS The PAH group was characterized by higher median serum IL-6 [2.38 (IQR 1.56-3.75) vs 0.87 (0.63-1.3) pg/ml, p=0.000003] and sIL-6R concentrations [69.7 (IQR 60.4-84.4 vs 45.7 (34.6-70.3) ng/ml, p=0.0036] compared to control subjects. Both groups did not differ in sgp130 concentrations. There were significant correlations in PAH group between IL-6 levels and uric acid, parameters of ventilatory efficiency in cardiopulmonary exercise testing: VE/VO2, VE/VCO2, VE/VCO2 slope and peak PetCO2. sIL-6R levels inversely correlated with LDL cholesterol. After 1 year the clinical deterioration occurred in 11 patients, 15 remained stable. Patients in whom the clinical deterioration occurred showed significantly higher baseline concentrations of IL-6 [3.25 (IQR 2.46-5.4) pg/ml vs 1.68 (1.38-2.78) pg/ml, p=0.004], but not sIL-6R. Median IL-6 ⩾ 2.3 pg/ml (91% sensitivity, 73% specificity) identified subjects with worse clinical course. In the univariate analysis, higher IL-6 level at baseline was associated with increased risk and earlier occurrence of clinical deterioration (HR 1.42, 95%CI 1.08-1.85, p=0.015). CONCLUSIONS IL-6 trans-signaling is enhanced in PAH. Elevated concentration of sIL-6R suggests its potential unfavorable role in systemic amplification of IL-6 signaling in PAH. Levels of IL-6 are associated with clinical indicators of disease severity as well as indirectly with systemic metabolic alterations. IL-6 shows prognostic value regarding predicting clinical deterioration.

Polymorphism of 9p21.3 Locus Is Associated with 5-Year Survival in High-Risk Patients with Myocardial Infarction

Objective The rs1333049, rs10757278 and rs4977574 are single nucleotide polymorphisms (SNPs) of chromosome 9p21 locus that are associated with prevalence of acute coronary syndromes (ACS). The rs1333049 SNP was also associated with cardiac outcome 6 months post ACS. No data concerning their association with long term prognosis after myocardial infarction is available. The aim of our study was to investigate the association of the 9p21.3 locus with 5-year overall mortality in patients with ST-elevation myocardial infarction (STEMI) treated invasively. Materials and Methods We performed a retrospective analysis of data collected prospectively in a registry of consecutive patients with STEMI treated with primary PCI. Genotyping was performed with a TaqMan method. The analyzed end-point was total 5-year mortality. Results The study group comprised 589 patients: 25.3% of females (n = 149), mean age 62.4±11.9 years, total 5-year mortality 16.6% (n = 98). When all the study group was analyzed, no significant differences in mortality were found between the genotypes. However, in high-risk patients (Grace risk score ≥155 points, n = 238), low-risk homozygotes had significantly better 5-year survival compared to other genotypes. The hazard ratio associated with high-risk genotype (high-risk homozygote or heterozygote) was: HR = 2.9 (95%CI 1.4–6.1) for the rs4977574 polymorphism, HR = 2.6 (1.25–5.3) for the rs1333049 one and HR = 2.35 (1.2–4.6) for the rs10757278 one (Cox proportional hazards model). Conclusions The 9p21.3 locus is associated with 5-year mortality in high-risk patients with STEMI. This finding, due to very high effect size, could potentially be applied into clinical practice, if appropriate methods are elaborated.

High-sensitivity C-reactive protein and total antioxidant status in patients with essential arterial hypertension and dyslipidemia.

PURPOSE To assess low-grade, systemic inflammation and antioxidant status as additional factors contributing to pathophysiology of essential arterial hypertension (HTN) and compare them with traditional risk factors, like abnormal lipids profile, considering their potential diagnostic usefulness. MATERIAL AND METHODS Serum high-sensitivity C-reactive protein (hs-CRP) concentrations and total antioxidant status (TAS) were measured in 143 subjects - 71 patients with diagnosed HTN and in 72 healthy controls. RESULTS In hypertensive patients, as compared to healthy control group, the median hs-CRP concentration was higher (2.0 mg/L, 25%; 75% quartile range: 0.1; 27.1 vs 0.4 mg/L, 25%; 75% quartile range: 0.0; 4.6, respectively, p<0.001) and TAS concentration lower (1.4 mmol/L, 25%; 75% quartile range: 1.0; 2.1 vs 1.5 mmol/L, 25%; 75% quartile range: 0.5; 1.8, respectively, p=0.048). Hypertensives had higher low-density lipoprotein cholesterol concentration (LDL-C) as well as triglycerides concentration (TG) and lower high-density lipoprotein cholesterol concentration (HDL-C). Higher diagnostic sensitivity was found for hs-CRP (87%) and for TAS (89%). According to the global linear regression analysis, age, gender, hs-CRP, TAS and HDL-C were the only parameters influencing the occurrence of HTN. ROC analysis identified hs-CRP, HDL-C and TG as statistically significant to diagnose HTN (0.839; 0.816 and 0.855, respectively). Moreover, in ROC analysis there were no differences in hs-CRP and TAS in females and males. CONCLUSIONS These results indicate that low-grade, systemic inflammation measured by hs-CRP as well as antioxidant status assessed by TAS, in the presence of traditional risk factors, are significant factors contributing to pathophysiology and diagnosis of essential arterial hypertension.

The rs12526453 Polymorphism in an Intron of the PHACTR1 Gene and Its Association with 5-Year Mortality of Patients with Myocardial Infarction

Objective The rs12526453 (C/G) is a single nucleotide polymorphism in an intron of the PHACTR1 gene (phosphatase and actin regulator 1). The C allele is associated with increased risk of coronary artery disease in an unknown mechanism. We investigated its association with long-term overall mortality in patients with ST-elevation myocardial infarction (STEMI) treated invasively. Methods Two independent groups of patients with STEMI were analyzed: a derivation group (n= 638) and a validation one (n=348). Genotyping was performed with the TaqMan method. The analyzed end-point was total long term mortality. Additionally, transcriptomic analysis was performed in mononuclear blood leukocytes from rs12526453 CC monozygotes or G allele carriers. Results In the study group (mean age 62.3 ± 11.9 years; 24.9% of females, n=159), percentages of CC, CG, and GG genotypes were 45.3% (n=289), 44.7% (n=285), and 10% (n=64), respectively. In the 5-year follow-up 105 patients died (16.46%). CC homozygotes had significantly lower mortality compared to other genotypes: 13.1% (n=38) vs. 18.3% in G-allele carriers (n=67), (p=0.017, Cox`s F test). In the validation group 47 patients died within 3 years (13.5%). We confirmed lower mortality of CC homozygotes: 10.1 % (n=18) vs. 16.95% in G-allele carriers (n=29), (p=0.031, Cox`s F test). Transcriptomic analysis revealed a markedly higher expression of NLRP-2 in CC homozygotes. Conclusions The rs12526453 CC homozygotes (previously associated with increased risk of myocardial infarction) showed, in 2 independent samples, better long-term survival. The finding of such high effect size, after appropriate validation, could potentially be translated into clinical practice.

Interleukin 6 modulates PPARα and PGC-1α and is involved in high-fat diet induced cardiac lipotoxicity in mouse.

BACKGROUND Interleukin 6 (IL-6) may be involved in regulation of cardiac lipid metabolism and mitochondrial function through its influence on peroxisome proliferator-activated receptors (PPARs). In this study we evaluated the impact of the physiological level of IL-6 on the expression of PPARα and PGC-1α in the heart and the effect of lack of this cytokine on high-fat diet (HFD) induced lipotoxicity. METHODS Male C57BL6/J wild type (WT) and IL-6 knock-out (IL-6KO) mice were used. 20 animals of each genotype were fed with HFD for 15-18weeks. Cardiac function was assessed using echocardiography and cardiomyocyte ultrastructure was examined using electron microscopy. QT-PCR and Western blotting were applied to estimate the expression of PPARα and PGC-1α at the transcriptional and protein levels. RESULTS At baseline WT and IL-6KO mice had similar size and function of the left ventricle. HFD induced similar left ventricular hypertrophic response in both groups without causing heart failure, but only WT animals had increased resting ejection fraction of the LV. Ultrastructure of HFD groups showed markers of lipotoxicity, that were more pronounced in IL-6KO group. In basal conditions IL-6KO animals had lower PPARα and similar PGC-1α expression as compared to WT. HFD induced downregulation of both PPARα and PGC-1α in WT animals, while in IL-6KO mice this effect was constrained. CONCLUSION IL-6 is involved in basal regulation of PPARα and PGC-1α expression in cardiomyocytes. The lack of this cytokine promotes high-fat diet induced lipotoxicity but without overt manifestations of cardiac failure.

MMP-9 in atrial remodeling in patients with atrial fibrillation

INTRODUCTION Atrial fibrillation (AF) is the most common arrhythmia and is associated with significant morbidity and mortality. The impact of matrix metalloproteinases (MMPs) on structural atrial remodeling and sustainment of AF in patients with persistent and permanent AF is unresolved. OBJECTIVES The aim was to evaluate MMP-9 and its tissue inhibitor-1 (TIMP-1) as markers of atrial remodeling in patients with persistent AF (PAF) who underwent electrical cardioversion (ECV) and in patients with permanent AF (continuous AF, CAF). PATIENTS AND METHODS Plasma levels of MMP-9 and TIMP-1, clinical findings, and echocardiographic parameters were evaluated in 39 patients with AF and in 14 controls with sinus rhythm. RESULTS The concentrations of MMP-9 were significantly higher in patients with PAF and CAF compared to controls. There was a significant increase of MMP-9 after ECV in the persistent AF group. The values of TIMP-1 were not significantly different between the groups. In patients with AF, MMP-9 levels were positively related to posterior wall thickness of the LV (r=0.356, P=0.049) and body mass index (r=0.367, P=0.046). CONCLUSION Elevated levels of MMP-9 were related to the occurrence and maintenance of AF. This suggests that MMP-9 can be a marker of atrial remodeling in patients with AF. Regulation of the extracellular collagen matrix might be a potential therapeutic target in AF.