Paraoxonase and arylesterase activities in stent restenosis in bare metal stent.

BACKGROUND AND OBJECTIVE: The serum paraoxonase and arylesterase activities are related to coronary artery diseases. However, there are a few data about the association of paraoxonase and arylesterase activities with in-stent restenosis (ISR). The aim of this study was to evaluate the relationship between paraoxonase and arylesterase activities and ISR in patients with bare metal stent (BMS). MATERIALS AND METHODS: Thirty-one patients with normal coronary artery (group 1) and 60 with BMS were enrolled in this observational study. According to the ISR, the patients were classified as group 2, without the ISR (n=29) and group 3, with the ISR (n=31). Serum paraoxonase and arylesterase activities were measured spectrophotometrically. RESULTS: The paraoxonase and arylesterase activities were lower in patients with BMS than in the individuals with normal coronary artery (P < 0.001 and P = 0.001, respectively). The enzyme activities were also higher in patients without ISR than with ISR (both of P < 0.001). In bivariate correlation analyses in patients with BMS, ISR shows significant positive correlations with the presence of hypertension and hyperlipidemia, type C lesion, and stent length, but shows negative correlations with type A lesion stent diameter, high-density lipoprotein cholesterol, and paraoxonase and arylesterase activities. In regression analysis, ISR is independently associated with paraoxonase and arylesterase activities (ß = -0.216, P = 0.038 and ß = -0.452, P < 0.001, respectively), type A lesion (ß = -0.251, P = 0.013), and stent diameter (ß = -0.192, P = 0.024) in patients with BMS. CONCLUSION: Our study shows that decreased paraoxonase and arylesterase activities play a significant role in ethiopathogenesis ISR in patients with BMS.

Effects of statin use on total oxidant and antoxidant capacity and ceruloplasmin activity.

PURPOSE: Oxidative damage plays an important role in atherosclerosis development. Statin drugs have anti-oxidant properties, but the clinical value of their antioxidant properties remains unclear. In this study, our aims were: (1) to assess the anti-oxidant effects of statins in patients with coronary artery disease (CAD) using a newly developed valid measure of total oxidant and anti-oxidant capacity; and (2) to identify whether statins influence ceruloplamin levels. METHODS: Within a cross-sectional study, 67 dyslipidemic CAD patients on atorvastatin for at least three months were compared with 69 age- and gender-matched CAD patients not using atorvastatin. All patients were either newly-diagnosed with or already had established CAD. Patients and controls were selected from among patients who had undergone coronary angiography for a variety of reasons. Immediately prior to angiography, plasma total oxidant and antioxidant capacity and ceruloplasmin (Cp) levels were measured by means of a relatively new and highly-reliable method. RESULTS: Total oxidant capacity levels were significantly lower and total antioxidant capacity significantly higher in those on atorvastatin; serum seruloplasmin levels also were significanly increased in the atorvastatin groups (all p < 0.05). On multivariate analysis, atorvastatin use was a significant determinant of Cp increase, independent of any antioxidant effect. CONCLUSIONS: This study clearly demonstrates increased anti-oxidant capacity and decreased oxidative stress with statin use. Atorvastatin use may also increase Cp levels although this effect appears to be independent of its anti-oxidant effects.

N-acetylcysteine fails to prevent renal dysfunction and oxidative stress after noniodine contrast media administration during percutaneous coronary interventions.

INTRODUCTION: Oxidative stress is believed to have a role in contrast-induced nephropathy. Based on this assumption, several known antioxidants have been studied to assess their effect on nephropathy, especially N-acetylcysteine (NAC). However, its usefulness has yet to be confirmed. OBJECTIVES: We aimed to assess whether NAC has any protective effect on contrast-induced renal dysfunction, and whether NAC affects the parameters of oxidative stress in serum and urine. PATIENTS AND METHODS: Sixty patients with coronary artery disease, who presented for an elective percutaneous coronary intervention (PCI), were randomized into 2 groups in an age- and gender-matched fashion: one group received 600 mg intravenous NAC and the other did not. Before and 24 hours after the procedure, blood and urine samples were obtained to assess total oxidant capacity (TOC), total antioxidant capacity (TAC), oxidative stress index (OSI), and renal function. RESULTS: Twenty-four hours after PCI, TOC and OSI levels were significantly increased and TAC levels significantly decreased, both in serum and urine. However, we did not observe any differences in oxidative parameters between patients who received NAC and those who did not. Multivariate analyses identified no protective effect of NAC on renal function, and no effect on oxidative parameters in either serum or urine. CONCLUSIONS: In this first clinical study that determined TOC and TAC levels in both serum and urine after exposure to contrast media, NAC was not found to affect oxidant parameters or protect against contrast nephropathy, at least in patients without the risk factors for nephropathy, such as diabetes mellitus or baseline renal or cardiac dysfunction.

The relationship between oxidative stress and coronary artery ectasia.

BACKGROUND: Whereas coronary artery ectasia (CAE) is a rare abnormality of the coronary arteries, co-existent coronary artery disease (CAD) is commonly seen in CAE patients. Since a causative relationship has been shown to exist between oxidative stress and CAD, we sought to determine whether any relationship exists between oxidative stress and CAE. METHODS: Fourty four patients with CAE (without CAD) and 86 controls (without any coronary disease) were recruited from among 1,520 patients undergoing coronary angiography. CAE subgroups were determined in accordance with the Markis classification system. Mean values for serum total oxidant status (TOS), total antioxidant status (TAS) and the oxidative stress index (OSI) were statistically compared between these two study groups and among CAE subgroups, with p = 0.05 set as the threshold for statistical significance. RESULTS: TOS and OSI were significantly increased (p = 0.018 and 0.0002) and TAS decreased (p = 0.031) in the CAE versus control group. TOS and TAS were independently related to CAE (p = 0.037 and 0.039), with an r(2) of 0.127. Interestingly, however, among CAE subgroups, no differences were observed. CONCLUSIONS: Oxidative stress might be implicated in the pathogenesis of CAE. Clinically-defined CAE subgroups did not differ in terms of oxidative stress status. However, the clinical implications of these findings are unclear and warrant further investigation.

Serum prolidase activity in idiopathic and ischemic cardiomyopathy patients.

Idiopathic and ischemic dilated cardiomyopathies (DCM) are the most common types of DCM, and both exhibit the same histopathological feature of fibrosis. Prolidase is an enzyme that serves a rate-limiting function in collagen turnover. Several studies have shown increased prolidase activity in fibrosis, though controversy persists. In this study, we measured prolidase enzyme activity in patients with idiopathic or ischemic DCM and in healthy controls, making this, to our knowledge, the first study to do so. What we found is that serumprolidase activity was significantly lower in both DCM groups relative to healthy volunteers and lower in ischemic DCM than idiopathic. These intriguing results could be attributed either to decreased collagen turnover in the heart tissues in which DCM develops, a result of diminished functional heart tissue, or to decreased physical activity levels among DCM patients stemming from their heart failure. Either way, further studies are needed to verify and clarify our results.

N-terminal pro-brain natriuretic peptide in cases with metabolic syndrome and its relationship with components of metabolic syndrome and left ventricular mass index.

OBJECTIVE: In this study we investigated N-terminal pro-brain natriuretic peptide (Nt-proBNP) levels in patients with metabolic syndrome (MetS) and its relationship between MetS components. METHODS: Thirty nine recently diagnosed MetS cases and 59 control cases were included in the present study. Left ventricular mass index (LVMI) was calculated and Nt-proBNP was determined. RESULTS: Both groups were similar in terms of age and sex. Body mass index were significantly higher in MetS than non-MetS. LVMI measurements were not different between MetS and control groups (p=0.168). Nt-proBNP levels were similar in both groups (p=0.954). There was a significant correlation between Nt-proBNP and LVMI, age, serum LDL- and HDL-cholesterol levels. Nt-proBNP was independently related with age (beta=0.357, p=0.015) and LDL-cholesterol (beta=-0.255, p=0.049) in the multivariate analysis. CONCLUSIONS: Nt-proBNP levels don't have a significant increase in MetS. But there was a significant relationship between Nt-proBNP levels and age and LDL-cholesterol.