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ABSTRACT: The aim of this study was to assess relationship of insulin resistance, oxidant-antioxidant status, endothelial dysfunction, lipid metabolism, and their contribution to the risks of cardiovascular disease in women with polycystic ovary syndrome (PCOS). Forty-five women with PCOS and 17 healthy women were included in this study. Nitric oxide (NO), endothelin-1 (ET-1), malondialdehyde (MDA), Apo A1, Apo B, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), total cholesterol (TC), triglyceride, small, dense LDL cholesterol (sdLDL-C), large buoyant LDL cholesterol (LbLDL-C) levels, and paraoxonase 1 (PON1) activity were measured in serum/plasma obtained from study groups. Insulin resistance [homeostasis model assessment (HOMA) index] and serum sex hormone binding globulin (SHBG), total testosterone (tT), free testosterone (fT), androstenedione, and dehydroepiandrosteronsulfate (DHEAS) levels were also evaluated. Significantly decreased SHBG, NO, HDL-C levels, and PON1 activities, but increased tT, fT, androstenedione, DHEAS, HOMA index, MDA, ET-1, LDL-C, sdLDL-C, and LbLDL-C values were found in PCOS patients compared with those of controls. There was a positive correlation between MDA and fT levels; and a negative correlation between PON1 activity and fT. Our data show that insulin resistance, dyslipidemia, endothelial dysfunction, and oxidative stress might contribute to the excess risk of cardiovascular disease reported in PCOS patients.
Gynecological Endocrinology 06/2012; 28(7):497-501. · 1.58 Impact Factor
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ABSTRACT: Oxidative stress is an important pathophysiological mechanism in non-alcoholic steatohepatitis (NASH). We aimed to evaluate serum xanthine oxidase (XO) (as a generator of reactive oxygen species), superoxide dismutase (SOD), glutathione peroxidase (GSHPx), paraoxonase (PON1) activities, nitric oxide (NO) and thiol levels in patients with NASH.
A total of 35 patients with NASH and 31 age-and-gender-matched healthy subjects were enrolled in the study as control group. Serum levels of XO, NO, SOD, GSHPx, PON1 and thiol were determined by spectrophotometric methods.
Serum XO activities were higher in the patients with NASH than the controls (p<0.001). Serum NO levels, SOD, GSHPx, PON1 activities and thiol levels were lower in the patients with NASH than the controls (p<0.031, p<0.019, p<0.001, p<0.001, p<0.001, respectively).
Increased oxidative stress in patients with NASH may result in a pro-oxidation environment, which in turn could result in decreased antioxidant enzyme activities and NO levels. Therefore effective antioxidant therapy to inhibit oxidative stress is necessary and agents to increase antioxidant enzyme may be a therapeutic option in NASH.
Clinical Biochemistry 08/2007; 40(11):776-80. · 2.08 Impact Factor
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ABSTRACT: Our objective was to investigate antioxidant paraoxonase 1 (PON1) activity together with malondialdehyde (MDA) levels to evaluate oxidative stress in patients with age-related macular degeneration (AMD), an important cause of blindness in the elderly population. Serum PON1 activity and MDA levels were analyzed in 37 patients with AMD and compared with 29 healthy controls using a spectrophotometric method. Serum MDA levels were significantly higher in the patient group (2.76 +/- 1.28 nmol/ml) than controls (1.00 +/- 0.36 nmol/ml; p < 0.001), whereas PON1 activity was lower in the patient group (132.27 +/- 63.39 U/l) than controls (312.13 +/- 136.23 U/l; p < 0.001). There was a negative correlation between MDA and PON1 levels (r = -0.470, p < 0.001). We conclude that the observed increase in MDA levels may be related to decreased PON1 activity; the present data also demonstrated that an obvious negative correlation between PON1 activity and MDA levels exists in patients with AMD. PON1 is also an antioxidant agent, therefore effective antioxidant therapy to inhibit lipid peroxidation is necessary and agents to increase PON1 activity may be a therapeutic option in AMD.
Ophthalmologica 02/2006; 220(1):12-6. · 1.42 Impact Factor
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ABSTRACT: We aimed to evaluate antioxidant paraoxonase 1 activity together with malondialdehyde (MDA) (an oxidative stress parameter) levels in patients with rheumatoid arthritis.
Fifty-seven rheumatoid arthritis patients were included in the study and subgrouped according to disease activity (active, n = 31; inactive, n = 26) and compared with healthy controls (n = 25). Serum paraoxonase 1 activity and MDA levels were measured according to an enzymatic spectrophotometric method.
Serum MDA level was higher (P = 0.001) whereas paraoxonase 1 activity was lower (P = 0.001) in the patient group than the controls. When active and inactive subgroups were compared with the control group, there was a statistically significant difference between each parameter. Serum MDA levels were significantly higher, while paraoxonase 1 activity was lower in the active and inactive rheumatoid arthritis groups than the control group. But there was not any difference between active and inactive patients with RA. There was a negative correlation between MDA levels and paraoxonase 1 activity.
Increased reactive oxygen species levels in rheumatoid arthritis may result in a pro-oxidation environment, which in turn could result in decreased antioxidant paraoxonase 1 activity and increased MDA levels.
Clinical Biochemistry 11/2005; 38(10):951-5. · 2.08 Impact Factor
