The effect of serum lipid levels on peripheral blood hematopoietic stem cell levels.

INTRODUCTION: There are limited numbers of available retrospective studies on various hematological diseases treated with stem cell mobilization therapy. In the present study, we aimed to demonstrate the effects of serum lipid levels on peripheral blood CD34+ (PBCD34+) cell counts as well as the changes in serum lipid levels during stem cell mobilization process. METHOD: PBCD34+ cell counts were compared between hypercholesterolemic patients and healthy individuals. Additionally, total cholesterol (TChol), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), and triglyceride (TG) levels were measured from healthy donors who underwent stem cell mobilization, at different time points (prior to filgrastim [phase 1], prior to apheresis [phase II], and the first week following apheresis [phase III]. RESULTS: In the hypercholesterolemia group, the PBCD34+ cell count was found to be higher among patients with elevated LDL-C (2.6 ± 0.35/µL vs. 1.7 ± 0.17/µL, p = 0.003) and TChol (2.6 ± 0.34/µL vs. 1.7 ± 0.14/µL, p = 0.006) in comparison to the healthy controls. In the mobilization group, phase II HDL-C levels (35.3 ± 2.8 mg/dL) were found to be lower than both phase I (45.6 ± 2.1 mg/dL) and phase III (44.5 ± 2.6 mg/dL) (p = 0.007). Phase II TChol levels (183.5 ± 10.0 mg/dL) were lower than both phase I (216.8 ± 8.5 mg/dL) and phase III (212.2 ± 8.4 mg/dL) (p = 0.02). At phase II, there was an inverse correlation between PBCD34+ cell count and HDL-C (r = - 0.57, p = 0.003). DISCUSSION: Our results indicate that, while increased LDL-C level is the determinant of baseline PBCD34+ cell count, reduced HDL-C is the determinant of PBCD34+ cell count during mobilization process.

Metoclopramide use to induce lactation can alter DRD2 and BDNF in the prefrontal cortex of offspring.

Metoclopramide, used as an anti-emetic drug in clinical practice, has recently also begun being used to establish hyperprolactinemic effects in breastfeeding. The purpose of this study was to investigate the potential side-effects of metoclopramide applied in the lactation period in the central nervous system of offspring rats. Eighteen female albino Wistar rats that had just given birth were divided into three groups together with their pups, healthy controls, low-dose metoclopramide (10 mg/kg, twice per day i.p.) and a high-dose metoclopramide group (45 mg/kg, twice per day i.p.). Brain tissues from six pups from each mother were harvested at the end of the 21st day. Immunohistochemical and ELISA techniques were performed using dopamine D2 receptor (DRD2), brain derived neurotrophic factor (BDNF) and neural growth factor (NGF), markers of extrapyramidal reaction in the brain, as signal molecules. Based on biochemical levels and immunohistochemical results, DRD2 expression decreased only in the external pyramidal layer neurons in the high-dose offspring group. Strong BDNF reaction was determined in pyramidal neurons in all layers in the control offspring group, and decreased reaction was observed in the high- and low-dose groups. No significant difference was observed in NGF expression between the three groups. Since high-dose metoclopramide caused a decrease in DRD2 expression in the external pyramidal layer in the prefrontal cortex, and since both high and low doses reduced BDNF expression, care needs to be taken with the use of metoclopramide in the lactation period due to the possibility of extrapyramidal reactions in offsprings.

Insulin resistance in children with familial hyperlipidemia.

Background The aim of the study was to investigate whether there is insulin resistance in children with familial hyperlipidemia (FHL) and to determine the factors affecting insulin resistance. Methods Hyperlipidemic children aged between 4 and 18 years and followed up with an FHL diagnosis were included in the study. The children of adults followed up with an FHL diagnosis were also recruited after the screening period. The scanned children were divided into two groups as hyperlipidemic and normolipidemic. A total of 77 patients of whom 52 were hyperlipidemic and 25 were normolipidemic were assessed in the study. Insulin resistance was evaluated (homeostatic model assessment of insulin resistance [HOMA-IR]) by performing the oral glucose tolerance test (OGTT). Results Of the patients, 36 were male and 41 were female; the average age was 11.6±3.9 years, and the body mass index (BMI) was established to be 20.3±4.4. In hyperlipidemic and normolipidemic patients, the following were determined: fasting insulin: 10.6 (±0.89) µU/mL, 4.9 (±0.45) µU/mL (p=0.000); 2-h insulin: 28.7 (±12.7) µU/mL, 18.9 (±10.5) µU/mL (p=0.000); and HOMA-IR: 1.9 (±0.17), 0.86 (±0.7) (p=0.000). No relationship was identified between lipid profiles and insulin resistance. Nevertheless, there was a positive correlation between insulin resistance and apolipoprotein B (Apo B) levels (0.52), and a negative correlation was determined in carnitine levels (-0.64). Conclusions Insulin resistance was established to be higher in children with FHL compared to normolipidemic children. Insulin resistance was not related to lipid phenotypes, but to Apo B levels and carnitine levels. Insulin resistance should be a routine method of evaluation in the follow-up of children with FHL.

Elevated glucose level at 30 minutes during an oral glucose tolerance test in obese adolescents: a new disorder of glucose tolerance.

We observed glucose levels >140 mg/dL measured at 30 minutes (min) during an oral glucose tolerance test (OGTT) in some obese patients. We aimed to investigate the significance of this finding by comparing lipid profiles, insulin resistance indices, and systemic inflammatory mediators between obese adolescents with normal glucose tolerance (NGT), impaired glucose tolerance (IGT), and elevated glucose levels at 30 min. The study involved 80 obese (body mass index >95(th) percentile for age and sex) adolescents (48 female, 32 male) between 11 and 16 years of age. Depending on OGTT results, patients were divided into NGT and IGT groups. The third group was recruited from the NGT group as having glucose levels > 140 mg/dL at 30 minutes. Lipid profiles, [interleukin-6 (IL-6)], neopterin, and lipoprotein associated phospholipase A2 (Lp-PLA2)] were assessed. Neopterin and Lp-PLA2 levels were significantly higher in obese adolescents with elevated glucose levels at 30 min. compared with those in both NGT and IGT groups (p=0.013, and 0.004, respectively). In these adolescents, IL-6 levels were significantly higher only than the NGT group (p=0.01). In logistic regression analysis, IL-6, neopterin and Lp-PLA2 levels were detected to be related to high blood glucose levels at 30 min (OR 1.11, p=0.01; OR 9.03, p=0.013; OR 1.01, p=0.004 respectively). Obese adolescents with elevated glucose levels at 30 min. demonstrated higher inflammatory mediators levels, which were atherosclerotic indicators, than obese adolescents with NGT and IGT. These results suggest that glucose levels >140 mg/dL measured at 30 min during an OGTT may be a new disorder of glucose tolerance in obesity.

The difference in lactate dehydrogenase activity between pre- and post-mobilization periods is a good indicator of successful stem cell mobilization.

Predicting poor stem cell mobilization may prevent the costs and complications associated with remobilization. We retrospectively reviewed the relationship between serum lactate dehydrogenase (sLDH) activity and peripheral blood CD34 (PBCD34) cell counts in 46 granulocyte colony stimulating factor (G-CSF) induced mobilization cycles with or without chemotherapy. A significant correlation between post-mobilization (pre-apheresis) sLDH activity and PBCD34 count was found (r(s)=0.43, p=0.007). A strong correlation was shown between the pre- and post-mobilization sLDH activity difference and PBCD34 count (r(s)=0.55, p=0.001). With respect to sLDH activity differences; (a) all patients with a difference of >300 U/L, (b) 71% of patients with a difference of 100-300 U/L, and (c) 44% of patients with a difference of <100 U/L were considered to have good mobilizations. The sLDH activity difference between pre- and post-mobilization is a good indicator of successful mobilization. According to our results, the success of mobilization can be predicted based on sLDH activity differences; (i) good mobilization if the difference is >300 U/L, (ii) intermediate risk if the difference is 100-300U/L, and (iii) high risk if the difference is <100 U/L.

Do cardiac risk factors affect the homocysteine and asymmetric dimethylarginine relationship in patients with coronary artery diseases?

OBJECTIVES: Elevated homocysteine (Hcy) concentrations have been shown to be a risk factor for atherosclerotic vascular disease and thrombosis. Increased asymmetric dimethylarginine (ADMA) levels have been implicated in the pathogenesis of numerous conditions affecting the cardiovascular system. In this study, the influence of cardiovascular risk factors and other variables on Hcy and ADMA relationship in patients with coronary artery disease (CAD) was investigated. DESIGN AND METHODS: Seventy-five patients with CAD were divided into three tertiles according to their Hcy levels. The effect of age, gender, blood pressure, lipid profile, renal function, and the presence of diabetes, insulin resistance, heart failure, inflammation, overweight, smoking and severity of coronary atherosclerosis on Hcy and ADMA relationship was evaluated. RESULTS: ADMA concentrations of patients in the middle and highest Hcy tertiles were significantly higher than the patients in the lowest tertile. When ADMA concentrations were adjusted for demographic, clinical and laboratory variables, the significant differences in ADMA concentrations between the tertiles were preserved. ADMA levels positively correlated with Hcy. Homocysteine levels positively correlated with serum creatinine and NT-proBNP concentrations and negatively correlated with glomerular filtration rates. Stepwise multiple regression analysis revealed Hcy as the unique predictor of ADMA levels. CONCLUSION: Homocysteine concentration has an effect on ADMA levels. There is a strong correlation between Hcy and ADMA. Cardiovascular risk factors do not have an influence on this relationship.

The effect of cholesterol levels on hematopoietic stem cell mobilization.

Data regarding effects of cholesterol levels on hematopoietic stem cell mobilization are limited. We retrospectively reviewed the relationship between serum total cholesterol levels and peripheral blood CD34 (PBCD34) cell counts in 52 granulocyte colony stimulating factor (G-CSF) induced mobilization cycles with or without chemotherapy. The cholesterol levels between the poor and good mobilization groups (median 172mg/dl vs. 183.5mg/dl, respectively, p=0.18) were not different. No significant correlation was obtained between the cholesterol levels and PBCD34 counts (r=0.02, p=0.85). No significant correlation was obtained between cholesterol levels and PBCD34 counts in patients neither mobilized with G-CSF alone (r=-0.02, p=0.9) nor G-CSF plus chemotherapy (r=0.04, p=0.8). The results of the study indicate that there was no effect of cholesterol on hematopoietic stem cell mobilization. Prospective cohort studies are needed to demonstrate the effect of cholesterol on mobilization and its extent in humans.

Inflammatory marker levels in obese adolescents with glucose intolerance: increased chitotriosidase activity.

OBJECTIVES: Existence of low grade persistent inflammation in obese children may increase the risk of metabolic and cardiovascular events. The aim was to determine whether glucose intolerance has an influence on inflammatory markers in obese adolescents. DESIGNS AND METHODS: 45 obese adolescents (mean BMI: 30.34±5.42 kg/m²) were grouped as normal or impaired glucose tolerance. IL-6 and CRP levels were analyzed by commercially available kits. Chitotriosidase activity was measured by a fluorescence method and neopterin levels were determined by ELISA. Data were expressed as mean±SD. RESULTS: IL-6 and CRP levels were similar in the two groups. Serum neopterin levels were not different between the groups. The chitotriosidase activity was significantly higher in the IGT group than NGT (124.33±51.97 µmol/L/h vs 84.50±53.99 µmol/L/h, p=0.04). CONCLUSION: Serum chitotriosidase activity is increased in obese adolescents with impaired glucose tolerance.

Fibroblast growth factor-19 levels in type 2 diabetic patients with metabolic syndrome.

This study aimed to examine fibroblast growth factor-19 (FGF-19) in type 2 diabetic (T2DM) patients with metabolic syndrome (MetS) and to evaluate the relationship between FGF-19 and other cardiovascular risk factors, such as atherogenic index of plasma (AIP) and hsCRP. 26 T2DM patients with MetS and 12 healthy controls were enrolled in the study. Serum FGF-19 levels were measured by sandwich ELISA, and compared with other cardiovascular risk factors; lipid profile, AIP, glucose, HbA1c, and hsCRP. AIP was calculated as log (TG/HDL-c). The median (1-3.quartile) FGF-19 levels in T2DM patients with MetS and healthy controls were 122.90 (108.63-237.60) pg/ml and 293.45 (153.64-370.31) pg/ml, respectively (P=0.003). Patients were also grouped by body mass index (BMI) <30 kg/m(2) (n=13) and ≥30 kg/m(2) (n=13) with median (1-3.quartile) FGF-19 values 168.70 (113.54-275.77) pg/mL and 115.89 (97.94-200.40) pg/mL, respectively (P=0.007). Significant negative correlations were found between FGF-19 and BMI, triglyceride, log (TG/HDL-c), hsCRP, and HbA1c (r=-0.526, P=0.001; r=-0.327, P=0.05; r=-0.312, P=0.05; r=-0.435, P=0.006; r=-0.357, P=0.028, respectively). We showed that FGF-19 levels are low in T2DM patients with MetS. The negative relationship between FGF-19 and several known cardiovascular risk factors such as TG, log (TG/HDL-c), hsCRP and HbA1c in diabetic patients with MetS suggests that FGF-19 can be used as a contributing marker.

The beneficial effects of physical exercise on antioxidant status in asthmatic children

Background: The pathogenesis of asthma involves both airway inflammation and an oxidant / antioxidant imbalance. It is demonstrated in asthmatic adults that exercise programmes improve lung function, a mechanism yet to be elucidated. The purpose of this study was to investigate the possible beneficial effects of physical exercise on antioxidant status in asthmatic children which may lead to a meliorated lung function. Methods: The study enrolled thirteen control and thirty asthmatic children. The asthmatic group was subdivided into two: the first group receiving only pharmacological treatment (n = 15) and the second receiving pharmacological treatment with exercise programme (n = 15) for 8 weeks. Blood samples were drawn from the subjects before and after treatment periods. As oxidant stress markers blood levels of malondialdehyde (MDA) and total nitric oxide (NO), and as antioxidant status, glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) enzyme activities were assessed. Results: Before any treatment was initiated, MDA and NO levels in the asthmatic group were significantly higher than the controls (3.40 ± 0.96 nmol / ml vs 2.46 ± 0.58 nmol / ml, and 12.53 ± 2.10 vs 9.40 ± 1.39 micromol/L, respectively). Both SOD (p = 0.0001) and GSH-Px (p = 0.023) activities were significantly lower in the asthmatic group. Pharmacological treatment and exercise programme together significantly improved lung performance and decreased the levels of oxidant stress markers, in concordance with a significantly increase in antioxidant enzyme activity measures when compared to the pharmacological treatment. Conclusion: Structured exercise programme in asthmatic children resulted in better lung function, which may be attributed to its effect on antioxidant status (AU)

Oxidative stress impairs endothelial nitric oxide levels in Behçets' disease.

BACKGROUND: Behçet's disease (BD) is an inflammatory vasculitis. Endogenous nitric oxide (NO), produced by endothelial cells, has pleiotropic effects such as vasodilatator, antiplatelet, antiproliferative. Reactive oxygen species (ROS) are produced at sites of endothelial inflammation. ROS target polyunsaturated lipids, which results in malondialdehyde (MDA) production. OBJECTIVE: The aim was to investigate the oxidative stress in BD patients by measuring MDA and total antioxidant status (TAS) levels and to establish a possible relationship with respect to NO levels regarding disease activity. MATERIALS AND METHODS: 55 BD patients (30 active/25 inactive) and 20 healthy volunteers were included in the study. Blood samples were drawn following an overnight fasting. TAS and MDA levels were determined spectrophotometrically. Serum nitrite (NO(2-)) and nitrate (NO(3-)) levels were measured to estimate NO production. Data were expressed as mean ± SD. RESULTS: TAS levels were significantly lower in BD patients than the controls (1.19 ± 0.34 vs. 3.29 ± 0.89 mmol/L). In the active BD group, MDA levels (0.36 ± 0.19 nmol/mL) were significantly higher than both the inactive BD group (0.25 ± 0.18 nmol/mL) and controls (0.18 ± 0.41 nmol/mL). NO levels were significantly lower in the active group compared to the inactive group (18.0 ± 2.80 vs. 19.40 ± 2.70 µmol/L). MDA levels correlated negatively with NO levels in the active group. CONCLUSION: Decreased NO levels mediated by increased oxidative stress significantly contribute to endothelial dysfunction observed in BD.

Biogerontology in Turkey: a brief report.

In this brief report, aging in biogerontology science perspective has been discussed based on the Turkish literature review with major key recommendations for future studies. Biogerontology in Turkey has focused on general retardation of the aging process giving priority to caloric restriction and oxidative stress mechanisms. The most popular investigation area for the scientists has been the oxidant and anti-oxidant systems in different tissues. However, the Turkish biogerontology science needs more manpower, economical and infrastructural and other resources for the promising studies in the future.

The beneficial effects of physical exercise on antioxidant status in asthmatic children.

BACKGROUND: The pathogenesis of asthma involves both airway inflammation and an oxidant/antioxidant imbalance. It is demonstrated in asthmatic adults that exercise programmes improve lung function, a mechanism yet to be elucidated. The purpose of this study was to investigate the possible beneficial effects of physical exercise on antioxidant status in asthmatic children which may lead to ameliorated lung function. METHODS: The study enrolled thirteen control and thirty asthmatic children. The asthmatic group was subdivided into two: the first group receiving only pharmacological treatment (n=15) and the second receiving pharmacological treatment with exercise programme (n=15) for 8 weeks. Blood samples were drawn from the subjects before and after treatment periods. As oxidant stress markers blood levels of malondialdehyde (MDA) and total nitric oxide (NO), and as antioxidant status, glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) enzyme activities were assessed. RESULTS: Before any treatment was initiated, MDA and NO levels in the asthmatic group were significantly higher than the controls (3.40±0.96 nmol/ml vs 2.46±0.58 nmol/ml, and 12.53±2.10 vs 9.40±1.39 micromol/L, respectively). Both SOD (p=0.0001) and GSH-Px (p=0.023) activities were significantly lower in the asthmatic group. Pharmacological treatment and exercise programme together significantly improved lung performance and decreased the levels of oxidant stress markers, in concordance with a significantly increase in antioxidant enzyme activity measures when compared to the pharmacological treatment. CONCLUSION: Structured exercise programme in asthmatic children resulted in better lung function, which may be attributed to its effect on antioxidant status.

Pleural fluid neopterin levels in tuberculous pleurisy.

OBJECTIVES: Neopterin is produced by stimulated macrophages under the influence of gamma interferon of lymphocyte origin. It is regarded as a biochemical marker of cell-mediated immune response. This study was designed to assess the diagnostic value of pleural fluid neopterin levels in tuberculous pleurisy in comparison with adenosine deaminase activity. DESIGN AND METHODS: Pleural fluid adenosine deaminase (ADA) activity and neopterin levels were measured in 16 patients with tuberculous pleurisy (TP) and 19 patients with malignant pleurisy (MP). ADA activity was determined by a colorimetric method, whereas neopterin levels were determined by a reversed-phase liquid chromatography technique. All values were given as median (min-max). RESULTS: The mean age was 45.43+/-20.39 years in the TP group and 60.42+/-11.02 years in the MP group (p=0.026). The median pleural fluid ADA activity was 51.75 U/L (3.50-62.40 U/L) in the TP group and was 2.30 U/L (1-8.20 U/L) in the MP group. The difference was statistically significant (p<0.001). The median pleural fluid neopterin levels were 13.15 nmol/L (1.86-59.50 nmol/L) and 2.44 nmol/L (0.92-27.60 nmol/L) in the TP group and the MP group, respectively (p=0.021). In order to evaluate the diagnostic value of pleural fluid neopterin concentrations, receiver-operating-characteristic curve analysis was performed. CONCLUSION: Pleural fluid neopterin concentration is significantly higher in TP when compared to MP, however when compared, its clinical use as a diagnostic marker is not valuable as ADA.

C-reactive protein and neopterin levels in healthy non-obese adults.

BACKGROUND: Obesity and increased waist-to-hip ratio, emphasizing the importance of truncal obesity, have been found to correlate positively with increased cardiovascular disease risk and mortality. Owing to the inflammatory nature of atherosclerosis, the aim of our study was to find possible correlations between body mass index and waist-to-hip ratio, and the inflammatory markers C-reactive protein (CRP) and neopterin in healthy lean and overweight adults. METHODS: A total of 49 healthy adults (mean age 42.4 +/- 1.8 years, 32 females and 17 males) were classified according to their body mass index (BMI) and waist-to-hip ratio values. CRP and neopterin levels were measured. RESULTS: CRP levels were found to be significantly higher in the group with BMI > or = 25 kg/m2 compared to the group with BMI < 25 kg/m2 (p = 0.014). Subjects with increased waist-to-hip ratio displayed significantly higher serum CRP and neopterin levels (p = 0.014 and p = 0.033, respectively) compared with the group in which the waist-to-hip ratio was < 0.9. A strong positive correlation was found between CRP and BMI in the whole group (r = 0.658, p = 0.0001). CONCLUSIONS: Grouping overweight subjects according to their waist-to-hip ratio, which is an indicator of truncal obesity, seems to be convenient in studying the inflammatory process in relation to the elevation of adipose tissue. Elevated CRP and neopterin levels may be useful in the assessment of cardiovascular risk in overweight as well as obese subjects.

Treatment and prophylaxis with sucralfate ameliorates hypoxia/reoxygenation-induced intestinal injury in pup rats.

BACKGROUND: Sucralfate is widely used as a cytoprotective agent in patients with peptic ulcer and other intestinal mucosal injury. The aim of this study is to investigate whether sucralfate has any effect on the prevention and treatment of hypoxia/reoxygenation-induced intestinal injury. MATERIAL/METHODS: Four groups of 10 1-day-old rat pups were studied. Hypoxia/reoxygenation (H/O)-induced intestinal injury was created. Group 1 was subjected to H/O just after birth and sacrificed at the end of the third day (Treatment Control). Group 2 was subjected to H/O just after birth and treated with sucralfate for 3 days. They were sacrificed at the end of the third day (Treatment). Group 3 was subjected to H/O on the third day after birth and then sacrificed (Prophylaxis Control). Group 4 was treated with sucralfate for the first 3 days, then H/O was created. Just after H/O, the pups were sacrificed (Prophylaxis). The intestinal tissues were harvested for histopathological investigation. Malondialdehyde (MDA) levels in the intestinal tissues were determined. RESULTS: The mucosal injury grades of the treatment and prophylaxis groups were significantly lower than those of control groups (p<0.05). The mean MDA level in the treatment and prophylaxis groups were 0.42+/-0.17 and 0.21+/-0.23 nmol/mg respectively. The MDA levels of both groups were significantly lower than in the control groups (p<0.05). CONCLUSIONS: The present study shows that sucralfate has beneficial effects in an experimental model of hypoxia/reoxygenation-induced intestinal injury.

Effects of L-arginine and L-carnitine in hypoxia/reoxygenation-induced intestinal injury.

BACKGROUND: This study was designed to show the role of oxidative stress, nitric oxide and glutathione-related antioxidant enzymes in hypoxia/reoxygenation (H/R)-induced intestinal injury model in mice and to evaluate the potential benefits of arginine and carnitine supplementation. METHODS: A total of 28 young Balb/c mice were divided into four groups: Group 1 (untreated) was given physiological saline before the experiment; group 2 H/R mice were supplemented with L-arginine; group 3 H/R mice were given L-carnitine for 7 days; and group 4 mice served as controls. At the end of day 7, H/R injury was induced and intestinal tissue malondialdehyde (MDA), nitrate levels and glutathione peroxidase (GSH-Px), glutathione reductase (GR) and glutathione-S-transferase (GST) activities were measured. RESULTS: MDA levels were higher in the untreated animals than in the other three groups. MDA levels were higher in the L-arginine-treated animals than in the L-carnitine-treated animals. Nitrate levels were found to be increased in the L-arginine-treated group when compared to the controls. GSH-Px and GR activities were increased in the untreated, the L-arginine and the L-carnitine-treated H/R groups when compared to the control group. GST activities were indifferent between the groups. CONCLUSIONS: Oxidative stress contributes to the pathogenesis of H/R-induced intestinal injury. The glutathione redox cycle may have a crucial role in the H/R-induced intestinal injury. L-arginine and L-carnitine supplementations ameliorate the histological evidence of H/R-induced intestinal injury and decrease lipid peroxidation but do not alter the glutathione-related antioxidant enzyme activities.

Association between serum paraoxonase activity and oxidative stress in acute coronary syndromes.

OBJECTIVE: The oxidation of low-density lipoprotein (LDL) is believed to have a central role in atherogenesis. Under oxidative stress not only LDL, but all other serum lipids are exposed to oxidation. High-density lipoprotein (HDL)-associated paraoxonase (PON1) was shown to inhibit LDL and HDL oxidation. We investigated the relationship between PON1 and oxidative stress in acute myocardial infarction and unstable angina in a comparative fashion. METHODS AND RESULTS: Activities of PON1, concentrations of malondialdehyde (MDA), lipids and lipoproteins were measured in patients (38 subjects with acute myocardial infarction and 33 subjects with unstable angina pectoris) and in age- and sex-matched controls (32 subjects). Serum PONI activity was significantly lower in patients than in controls (p < 0.001). Patients had significantly increased serum MDA concentrations (p < 0.001) and there were strong negative correlations (p < 0.001) between serum PON1 and MDA levels in the acute myocardial infarction group (r = -0.673), in the unstable angina pectoris group (r = -0.868) and in healthy controls (r = -0.778). Serum HDL-cholesterol (HDL-C) concentrations were lower in patients than controls (p < 0.05). No correlation was observed between PON1 and HDL-C levels in patients or controls. Apo A I concentrations were significantly lower in the patient groups (p < 0.01), but were insignificant between patients with AMI and UAP. Apo A-I and PON1 levels did not show any correlation. Apo B concentrations were lowest in the healthy controls, higher in the UAPgroup and highest in the AMI group (p < 0.001). In the acute myocardial infarction group LDL/apo B ratio was lower than in healthy controls and in the UAP group, suggesting smaller LDL particle size. CONCLUSIONS: Results of this study indicate that lower serum PON1 activity is associated with oxidative stress and the activity of PON1 is not related to HDL-cholesterol.

Nitric oxide and oxidative stress in atherosclerotic renovascular hypertension: effect of endovascular treatment.

PURPOSE: Because activation of the renin-angiotensin system leads to an increase in oxidative stress, the authors investigated nitric oxide (NO; nitrite + nitrate), superoxide dismutase (SOD), catalase, and malondialdehyde (MDA) levels and the effect of endovascular treatment on these parameters in patients with atherosclerotic renovascular hypertension. The relationship of NO with blood pressure and renal functional indexes was also investigated. MATERIALS AND METHODS: In this prospective cohort study, serum creatinine, NO, SOD, catalase, plasma MDA, urinary microalbumin, and NO levels, and blood pressure were determined in 21 patients with hypertension and unilateral renal artery stenosis caused by atherosclerosis at entry and after 24 hours, 2 weeks, and 6 weeks of endovascular treatment. RESULTS: MDA concentrations decreased 24 hours after intervention and remained low 2 and 6 weeks later. In addition, serum SOD and NO and urine NO levels were increased significantly 24 hours after endovascular treatment and decreased after 2 and 6 weeks. However, serum catalase levels did not differ after the intervention. Blood pressures decreased after treatment. There were no significant differences in urinary microalbumin levels, estimated glomerular filtration rates, and creatinine levels after endovascular treatment. CONCLUSIONS: Endovascular treatment decreases oxidative stress and may offer new benefits in the treatment of patients with hypertension associated with renal artery stenosis. The decrease in oxidative stress and/or the upregulation of SOD may increase the bioavailability of NO, which in turn may lead to the rapid hypotensive response.

Effects of the calcium channel blocker amlodipine on serum and aortic cholesterol, lipid peroxidation, antioxidant status and aortic histology in cholesterol-fed rabbits.

Reactive oxygen metabolites and oxidized fatty acids are proinflammatory and are involved in the pathophysiology of atherosclerosis. Amlodipine, a unique third-generation dihydropyridine-type calcium channel blocker, seems to exert atheroprotective effects through its antioxidant properties related to its chemical structure and independent of its calcium channel-blocking effect. In this study, the interactions of amlodipine with major cellular antioxidants were investigated in order to elucidate the mechanisms underlying its atheroprotective effects. New Zealand white male rabbits were fed regular chow (group 1), chow with 1% cholesterol (group 2), regular chow plus 5 mg/kg/day amlodipine per os (group 3) and 1% cholesterol plus amlodipine (group 4) for 8 weeks. Total cholesterol, malondialdehyde (MDA) and vitamin E concentrations and catalase and superoxide dismutase (SOD) activities were determined in blood drawn before and after the experimental period. Aortic tissue was examined for atherosclerotic changes and aortic total cholesterol, MDA, catalase and SOD were determined. At the end of the 8-week treatment period, serum total cholesterol and plasma MDA were elevated in groups 2 and 4. In group 2, serum vitamin E and plasma SOD diminished (p < 0.05) and catalase increased (p < 0.05). In group 4, SOD activity increased at the end of treatment. MDA levels were lower and plasma SOD activities were higher in group 4 than in group 2. Aortic tissue investigations revealed higher total cholesterol and MDA concentrations and catalase activities in group 2 than in group 4, and the highest tissue SOD activity was recorded in group 4 (p < 0.05 for all comparisons). Morphological examination of aortic tissues exhibited endothelial disarrangement and lipid deposition in group 2. Histopathological alterations related to atherogenesis were less in group 4 than in group 2. Amlodipine seems to exert atheroprotective effects by reducing aortic cholesterol accumulation and blood and aortic lipid peroxidation, enhancing SOD activity both in blood and aortic tissue and suppressing the consumption of vitamin E. On the other hand, the suppression of catalase activity in blood and the aorta interferes with the drug's well-known antioxidant effects.