Marcin Kożuch

CCN2 protein is an announcing marker for cardiac remodeling following STZ-induced moderate hyperglycemia in mice

Diabetes causes changes in the myocardium, which are often called diabetic cardiomyopathy. This condition has been extensively investigated in animal models with high glucose levels. Nevertheless, it has not been investigated whether moderate hyperglycemia, in the absence of other features of metabolic syndrome, may also cause similar changes in the heart. The aim of the study was to assess changes in the myocardium in an animal model of mild type 1 diabetes. Moderate hyperglycemia was induced in 8- to 10-week-old male C57BL6J mice by 5 intraperitoneal injections of streptozotocin (40 mg/kg). After 16 weeks, they were sacrificed, and left ventricle (LV) dimensions and extent of cardiac fibrosis were assessed by morphometry. The abundance of CCN proteins in LVsamples was assessed using western blotting, while activity of metalloproteinase 2 was established in zymography. Real time PCR was used to investigate the expression of transforming growth factor beta1 (TGFbeta1) and atrial natriuretic peptide. Mice with moderate hyperglycemia presented comparable cardiac dimensions with fibrosis and hypertrophy parameters as the non-diabetic controls. However, the abundance of profibrotic CCN2 protein was significantly increased in hyperglycemic animals (1.67 +/- 0.28 vs. 1 +/- 0.47, p < 0.05). Interestingly, this change was independent from the TGFbeta1 expression, as its RNA abundance was similar in both groups. Moderate hyperglycemia also caused an increase in the activity of the metalloproteinase 2 (1.21 +/- 0.17 vs. 1 +/- 0.07, p < 0.05). Despite diabetes, no profound changes in cardiac morphology were found. In our animal model, moderate hyperglycemia caused activation of a profibrotic gene expression program, which was counterbalanced by the increase of metalloproteinase activity.

Coronary sinus concentrations of interleukin 6 and its soluble receptors are affected by reperfusion and may portend complications in patients with myocardial infarction

UNLABELLED Interleukin 6 (IL-6) is a pleiotropic cytokine involved in both inflammatory reaction and myocardial response to stress. Its effects largely depend on the concentration of the soluble receptors (sIL-6R and sgp130). We investigated the production of IL-6, sIL-6R and sgp130 by the heart during ischemia and reperfusion. METHODS The levels of IL-6 were determined in blood of 34 patients with first myocardial infarction (STEMI), left anterior descending (LAD) artery occlusion, otherwise normal coronaries, without significant co-morbidities and 16 comparable subjects with stable ischemic heart disease and lesion in LAD. Blood samples from coronary sinus (CS) and aorta (Ao) were drawn before percutaneous intervention (PCI), immediately after and at the end of the procedure. Venous blood from 30 healthy volunteers served as control. RESULTS STEMI patients presented high IL-6 concentrations that increased further after reperfusion when its levels in CS became significantly higher than in Ao. In both groups prior to the PCI there were significantly higher concentrations of sIL-6R in Ao than in CS. This difference disappeared immediately after reperfusion. STEMI patients who experienced cardiovascular complications had higher IL-6 concentration and higher transcardiac sIL-6R gradient than patients with event-free hospitalisation. This association was confirmed in multivariate logistic regression analysis. Myocardial infarction increases concentration of IL-6 that is further elevated by reperfusion. A transcardiac gradient of sIL-6R during ischemia may indicate that large amounts of soluble IL-6 receptors are bound to the infarcted heart and thus affect signal transduction. IL-6 and initial sIL-6R gradient may portend complications in STEMI patients.

Which Method of GFR Estimation Has the Best Prognostic Value in Patients Treated with Primary PCI: Cockcroft–Gault Formula, MDRD, or CKD-EPI Equation?—A 6-Year Follow-Up

Background/aims: The aim of this study was to determine the correlation between renal function and 6-year mortality in patients with acute myocardial infarction (AMI), treated successfully with primary percutaneous coronary intervention (PCI), and to examine whether Cockcroft–Gault (C-G) formula or Modification of Diet in Renal Disease (MDRD) study equation or CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation is the best predictor of very late mortality. Methods: A prospective cohort study with 6-year follow-up of a homogenous group of 193 patients, with ST-segment elevation AMI treated with successful primary PCI. Glomerular filtration rate (GFR) estimated by C-G formula, MDRD, and CKD-EPI equation were analyzed. Results: The patients with chronic kidney disease (CKD) had a much lower cumulative survival rate than those without it (p < 0.05). A larger area under the receiver-operating characteristic curve for death with respect to GFR for C-G formula was observed. In the multivariate analysis, only GFR ≥ 55 mL/min according to C-G formula was independently associated with lower mortality. Conclusion: CKD is associated with higher mortality after a successful primary PCI during a 6-year follow-up. C-G formula is better than MDRD and CKD-EPI equations at predicting mortality after AMI.

Oxidative stress and antioxidative defense parameters early after reperfusion therapy for acute myocardial infarction

Reperfusion of ischemic myocardium evokes rapid release of free radicals in experimental models. The aim of the study was to investigate the oxidative stress and antioxidative defense during first minutes after reopening of the infarct related artery in patients treated for acute myocardial infarction. The study group consisted of 15 patients with first ST elevation myocardial infarction (STEMI) due to left anterior descending artery occlusion. The control group included ten patients with stable ischemic heart disease (IHD). Blood samples from coronary sinus were drawn before, immediately after and about 15 min after angioplasty. Activity of superoxide dysmutase (SOD), concentration of glutathione as well as the concentrations of lipid peroxides, malodialdehyde (MDA) and 4-hydroxy-2-nonenal (HNE) were measured. There was significantly higher concentration of MDA and HNE and higher SOD activity in STEMI patients before the reperfusion, as compared to the stable IHD group. After the reperfusion concentration of HNE in erythrocytes from STEMI patients was higher than in IHD group. At the same time the activity of SOD significantly decreased in patients with impaired tissue perfusion (myocardial blush grade <2). In conclusion, there is a slightly higher concentration of oxidative stress parameters in patients with STEMI. Diminished antioxidative defense after reperfusion is associated with impaired myocardial perfusion.

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.

Early and long-term prognosis of patients with coronary artery disease treated with percutaneous coronary interventions in 2005. Experience of single large-volume PCI center

PURPOSE The progress which has been made in interventional cardiology contributes to the gradual improvement of the results of CHD (coronary heart disease) therapy. The aim of the study was the assessment of early and long-term prognosis in all the patients with CHD treated invasively in one large-volume PCI center in 2005. MATERIAL AND METHODS 1390 consecutive patients with CHD treated with PCI in 2005 were included in the analysis. Patients with ST-elevation myocardial infarction (STEMI) accounted for 50% of cases, patients with stable angina (SA) amounted to 25%, and patients with non-ST elevation acute coronary syndromes (NSTE-ACS) constituted 25%. Mean follow-up was 738 (±237) days. RESULTS The highest mortality during the hospitalization was noted within the STEMI group(SA vs. NSTE-ACS vs. STEMI; 0% vs. 0.3% vs. 4.1%, respectively; p<0.001). The highest mortality during a 2-year follow-up was also observed in the STEMI group (SA vs. NSTE-ACS vs. STEMI, 6.3% vs. 8.5% vs. 13.8%, respectively; p<0.001). Multiple regression model showed that independent risk factors for death during the follow-up were: age, glycaemia at admission, heart rate, blood pressure, ejection fraction, STEMI, ineffective PCI (R=0.3613; F(10.131)=19.672; p<0.0001 for the model). CONCLUSIONS The highest relative increase of mortality after the discharge of patients with CHD undergoing PCI referred to the patients with NSTE-ACS. However, in the real life PCI practice STEMI patients have the worst hospital and long-term prognosis. Well recognized risk factors for death in patients with CHD are still of great importance in negative prognosis of patients undergoing PCI.

Circadian variations of interleukin 6 in coronary circulations of patients with myocardial infarction.

UNLABELLED We hypothesize that higher morbidity of patients with ST-segment elevation myocardial infarction (STEMI) in the out-of-office hours differences in outcome after myocardial infarction may depend on the concentrations of inflammatory cytokines. The aim of the study was to determine the relation between the time of percutaneous coronary intervention (PCI) and local concentration of interleukin 6 (IL-6) and its soluble receptors (sIL-6R and sgp130) in patients with STEMI. METHODS AND RESULTS The study included 32 patients with invasively treated left anterior descending artery occlusion and no significant co-morbidities. Blood samples were drawn from coronary sinus and aorta before and after intervention. Patients admitted in the afternoon (13-20) presented significantly higher mean IL-6 levels in all samples than patients admitted in the morning. There was a positive correlation between time of intervention and concentrations of IL-6 in all samplings, but also with transcardiac IL-6 gradient at the end of procedure and IL-6 increase during PCI. We did not find any significant association between time of PCI and concentrations of sIL-6R and sgp130, time from pain to balloon, angiographic parameters or medical history. CONCLUSIONS Coronary concentration of IL-6 in patients with STEMI is significantly higher in the afternoon than in the morning. This might be involved in increased morbidity of those patients.

CCN1 expression in interleukin-6 deficient mouse kidney in experimental model of heart failure

Chronic heart failure often leads to worsening of the renal function. Mediators of this process include inflammatory and neuroendocrine factors. CCN1 (Cyr 61), a member of growth factor-inducible immediate early genes, which modulates inflammation and fibrogenesis, is excreted with urine in the early phase of acute renal injury and may be involved in the pathogenesis of the cardiorenal syndrome. The aim of the study was to evaluate CCN1 protein abundance and localization in the kidney of IL-6-deficient C57BL/6J (IL-6 KO) mice and respective wild-type (WT) animals in basal conditions and in animals with chronic heart failure twelve weeks after myocardial infarction. Age- and sex-matched mice from both strains subjected to sham operation served as controls. One group of WT animals subjected to myocardial infarction was treated with antagonist of AT1 receptor telmisartan over 12 weeks. Abundance and localization of CCN1 protein in kidney were assessed with Western blotting and immunohistochemistry, respectively. In all groups the strongest immunohistochemical reaction for CCN1 was observed in distal convoluted tubules and in smaller arteries, however, the total expression of CCN1 protein was lower in IL-6 KO mice in comparison to WT animals. The main difference in CCN1 distribution between the examined genotypes was lack of reaction in internal renal medulla and very weak reaction in proximal convoluted tubules in IL-6 KO mice. Experimental heart failure only slightly attenuated the expression of CCN1 protein in the kidney of WT mice and had no effect in IL-6 KO mice. Although, blockade of AT1 receptor did not alter CCN1 protein expression in kidneys of WT mice after myocardial infarction, it significantly changed its CCN1 distribution in the renal tubular system.

Atrial expression of the CCN1 and CCN2 proteins in chronic heart failure

Previous studies have reported the upregulation of CCN proteins early after acute heart injury. The aim of the present work was to evaluate the expression of the CCN1 and CCN2 proteins and their regulation by angiotensin II in the atrial myocardium of a chronically failing heart. Male adult mice were subjected to ligation of the left coronary artery to produce myocardial infarction (the MI group), and 16 of them were treated for 12 weeks with the AT1 receptor antagonist telmisartan (the MI-Tel group). Sham-operated mice served as controls. The expression of proteins was evaluated by immunohistochemistry 12 weeks after the operation. In shamoperated mice, stainings for CCN1 and CCN2 proteins were positive within atrial cardiomyocytes. CCN1-positive reaction revealed diffused cytoplasmic localization, while CCN2 was present mainly within the perinuclear cytoplasm. CCN1 was upregulated in the MI group, while CCN2 remained at basal level. Telmisartan prevented the upregulation of CCN1 and decreased CCN2 level. We compared the experimental data with the expression of CCN1 and CCN2 proteins in human right atrial appendages. We found an inverse, but not significant, relation between the level of either protein and the left ventricular ejection fraction. This suggests a similar atrial regulation of CCN1 and CCN2 expression also in humans. We conclude that in the murine atria, CCN1 and CCN2 proteins are expressed constitutively. In chronic heart failure, CCN proteins tend to be upregulated, which may be related to the action of angiotensin II.

Angiographically-Derived SYNTAX Score and Its Prognostic Value in Dialysis Patients: Comparison With the Khan Index

BACKGROUND The aim of this study was to assess the value of the angiographically-derived Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery (SYNTAX) score in predicting mortality and major adverse cardiac events (MACEs) during a 3-year follow-up of dialysis patients undergoing a percutaneous coronary intervention or coronary artery bypass graft operation. We compared the aforementioned results with the clinical Khan index. METHODS The SYNTAX score was calculated for 87 of 110 dialysis patients after coronary angiography. RESULTS The mean SYNTAX score was 12.75 ± 14.49. During the 3-year follow-up, 58% of the patients died, and 74% had at least 1 MACE. In a Kaplan-Meier survival analysis, the risk of death and MACEs increased in parallel with the SYNTAX score. A score greater than 12.75 was strongly associated with mortality and MACE (both Ps < 0.01). In receiver operating characteristic (ROC) curve analysis, the areas under the curves (AUCs) of the SYNTAX score and Khan index were significantly higher (both Ps < 0.001) than the area of diagnostic indifference. The predictive values for death as indicated by the SYNTAX score and the Khan index, respectively, were almost identical in the ROC analysis (AUC SYNTAX score, 0.6436; AUC Khan index, 0.6475; P = 0.9532). Areas under the ROC curves of both methods according to MACE were also significantly different from those for the random model (both Ps < 0.001). CONCLUSIONS The SYNTAX score is a powerful predictor of mortality and MACEs in dialysis patients undergoing percutaneous coronary intervention or coronary artery bypass graft during a 3-year follow-up. The score provides prognostic information similar to that provided by the Khan index.