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    Antioxidant enzyme activities, lipid peroxidation, and total antioxidant status in children with Henoch-Schonlein purpura
    (Springer, 2008) Ece, Aydin; Kelekci, Selvi; Kocamaz, Halil; Hekimoglu, Askin; Balik, Hasan; Yolbas, Ilyas; Erel, Ozcan
    The aim of this study was to assess the role of oxidative stress in the pathogenesis of Henoch-Schonlein purpura (HSP) vasculitis. The activities of catalase (CAT), arylesterase (ARYL), and paraoxonase (PON) as antioxidant enzymes and serum malondialdehyde (MDA) level as an indicator of lipid peroxidation, together with total antioxidant status (TAS), were measured in 29 children with HSP (mean age 9.3 +/- 2.7 years), both at the onset of the disease and at the remission period and in matched controls. Active-stage HSP had significantly higher MDA level (15.5 +/- 7.3 vs 7.8 +/- 3.9 nmol/l, respectively, P<0.001) and lower TAS (524 +/- 122 vs 699 +/- 122 mu mol Trolox Equiv/1, P< 0.001), PON (97 +/- 47 vs 136 +/- 95 U/1, P=0.042), ARYL (158 +/- 39 vs 212 +/- 52 U/1, P<0.001), and CAT (50 +/- 27 vs 69 +/- 20 U/1, P=0.002) activities compared with the control subjects. Although CAT (P>0.05) and PON (P>0.05) activities were found to be similar between active and remission stages of HSP, the active stage of the disease had significantly lower ARYL (P=0.011) and TAS (P=0.006) and higher MDA (P<0.001) values compared with remission period. Significant positive correlations were found between CAT and MDA (r=0.433, P=0.019) and between CAT and C-reactive protein (r=0.386, P=0.035) in the active stage of HSP. No significant differences were detected in oxidant/antioxidant parameters between patients with or without renal, gastrointestinal, or joint involvement (P>0.05). Increased oxidative stress and lipid peroxidation may play important roles in the pathogenesis of HSP vasculitis. Antioxidant therapeutic interventions in longlasting vasculitis and risk of atherosclerosis secondary to increased oxidant stress remain to be investigated.
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    Does ischaemia-modified albumin level predict clomiphene citrate resistant polycystic ovary syndrome patients?
    (Taylor & Francis Inc, 2021) Ege, Serhat; Bademkiran, Muhammet Hanifi; Peker, Nurullah; Erdem, Selami; Koceroglu, Rusen; Erel, Ozcan
    This study aims to examine the role of ischaemic-modified albumin (IMA) in predicting clomiphene citrate (CC) resistance in patients with CC-resistant and CC-sensitive infertile polycystic ovary syndrome (PCOS). Sixty women patients admitted to the infertility clinic were evaluated. The patients were divided into two groups. Group 1 comprised 30 infertile PCOS patients with CC resistance; group 2 was the control group comprising 30 infertile PCOS patients with CC sensitivity. Serum IMA levels of PCOS patients with CC resistance were significantly higher than CC sensitivity patients (p < .001). The independent variables BMI and age effects were adjusted according to the logistic regression method with groups. Significant differences were observed between the two groups in the levels of IMA (p = .0005), HOMA-IR (p = .0045), insulin (p = .022), free testosterone (p = .0001) and total testosterone (p = .03) values. By using ROC curve analysis for IMA between study and control groups, cut off point of IMA was calculated as 0.505 U/mL, sensitivity was 80% and specificity was 63%. The area under the curve was 0.926. This shows us that more oxidative stress (OS) occurs in the CC-resistant group. As a reflection of OS in the follicular endocrine, microenvironment may be linked with impaired oocyte developmental competence and embryo quality in association with increased IMA, free testosterone, total testosterone, insulin and HOMA-IR levels.Impact statement What is already known on this subject?In previous studies, IMA was compared between PCOS and control groups. In this study, serum IMA levels were measured in infertile PCOS patients resistant to CC for the first time. What the results of this study add?Serum IMA levels were significantly higher in resistant infertile PCOS patients compared to the control group. This shows us that more OS occurs in the CC-resistant group. What the implications are of these findings for clinical practice and/or further research?IMA will be a guide for PCOS management in patients with CC-resistant PCOS.
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    The effect of clomiphene citrate on oxidative stress parameters in polycystic ovarian syndrome
    (Taylor & Francis Inc, 2021) Peker, Nurullah; Turan, Gokce; Ege, Serhat; Bademkiran, Muhammet Hanifi; Karacor, Talip; Erel, Ozcan
    This study aimed to examine the possible association between the oxidative stress parameters and clomiphene citrate resistance in polycystic ovary syndrome. The demographic data, hormone profiles and oxidant and antioxidant values of 50 clomiphene citrate-resistant polycystic ovary syndrome patients (Group 1), 32 clomiphene citrate-sensitive polycystic ovary syndrome patients (Group 2) and 87 non-polycystic ovary syndrome patients (Group 3) were compared. The average age, follicle-stimulating hormone, oestradiol, thyroid-stimulating hormone and prolactin values of the three groups were found to be homogeneous. Ferroxidase, catalase and myeloperoxidase levels were determined to be lower in the clomiphene citrate-resistant group compared to clomiphene citrate-sensitive and non-polycystic ovary syndrome groups (p < .001). As a result, Polycystic ovary syndrome patients with clomiphene resistance had lower antioxidant (catalase and ferroxidase) levels compared to those who were sensitive to clomiphene and who did not have polycystic ovary syndrome. The myeloperoxidase levels also demonstrated the same trend, which might be due to a compensation mechanism.Impact Statement What is already known on this subject? In the literature, there are many studies evaluating the association between PCOS and oxidative stress. No research related to antioxidants in clomiphene citrate-sensitive and clomiphene citrate-resistant PCOS patients was found in the relevant literature. What do the results of this study add? In this study, the antioxidants catalase and ferroxidase were found to be lower in PCOS women compared to non-PCOS; however, they were the lowest in clomiphene citrate-resistant PCOS women. Interestingly, myeloperoxidase, which is a part of oxidative stress, was also found to be higher in the non-PCOS group.
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    Increased oxidative stress is associated with thiol/disulphide homeostasis in clomiphene citrate resistant polycystic ovary syndrome
    (Taylor & Francis Inc, 2021) Ege, Serhat; Bademkiran, Muhammet Hanifi; Peker, Nurullah; Ozgun, Zinet; Bagli, Ihsan; Erdem, Selami; Erel, Ozcan
    The purpose of this study was to evaluate the relation CC resistant PCOS and the thiol/disulphide homeostasis, used as a marker of OS, by measuring that exchange using a novel technique. Sixty women patients admitted to the infertility clinic were evaluated. The patients were divided into two groups. Group 1 comprised 30 infertile PCOS patients with CC resistance; Group 2 was the control group comprising 30 infertile PCOS patients with CC sensitivity. Serum total thiol (p = .024), native thiol (p = .0052), disulphide (p = .003), index 1 (p = .001), index 2 (p = .001) and index 3 (p = .001), HOMA-IR (p < .001) and free testosterone (p < .001) were statistically significant. The independent variables BMI and age effects were adjusted according to the logistic regression method with groups. Significant differences were observed between the two groups in the levels of native thiol (p* = .0042), total thiol (p* = .024), disulphide (p* = .0003), index 1 (p* = .0001) index 2 (p*= .0001), index 3 (p* = .0001), HOMA-IR (p* = .0044), insulin (p*= .032) and free testosterone (p* = .0001) values. The thiol/disulphide homeostasis viewed in favour of OS. Like a reflection of OS in the follicular endocrine microenvironment may be linked with increased thiol/disulphide homeostasis, free testosterone, insulin and HOMA-IR levels.Impact statement What is already known about this subject?In previous studies, thiol/disulphide homeostasis was compared between PCOS and control groups. In this study, serum thiol/disulphide homeostasis was measured in infertile PCOS patients resistant to CC for the first time. What do the results of this study add?Disulphide concentrations were significantly higher in patients with CC resistant patients thanthe control group. This shows us that more OS occurs in the CC-resistant group. What are the implications of these findings for clinical practice and further research?Thiol/disulphide homeostasis will be a guide for PCOS management in patients with CC-resistant PCOS.
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    Neutrophil activation, protein oxidation and ceruloplasmin levels in children with Henoch-Schonlein purpura
    (Springer, 2007) Ece, Aydin; Kelekci, Selvi; Hekimoglu, Askin; Kocamaz, Halil; Balik, Hasan; Yolbas, Ilyas; Erel, Ozcan
    The aim of this study was to investigate the role of neutrophil activation, protein oxidation and ceruloplasmin (CLP) in the pathogenesis of Henoch-Schonlein purpura (HSP), which has not been investigated previously. Serum activities of myeloperoxidase (MPO) and arylesterase (ARYL) and levels of free thiol groups, CLP and total oxidant status (TOS) were measured in 29 children with HSP at the onset of the disease and during remission in comparison with 30 healthy subjects. Patients at active stage had significantly higher MPO activity (391 +/- 277 vs. 155 +/- 154 U/l, P<0.001), higher CLP (832 +/- 120 vs. 682 +/- 114 mg/dl, P<0.001) and TOS values (20.7 +/- 11.8 vs. 7.5 +/- 2.8 mu mol H2O2/l, P<0.001) than the controls, respectively. Patients had significantly lower ARYL activity (158x10(3) +/- 3x10(3) vs. 187x10(3) +/- 4 46x10(3) U/l, P<0.001) and lower free thiol levels (234 +/- 48 vs. 279 +/- 26 mu mol/l, P<0.001) than the controls, respectively. Significantly positive correlations were found between TOS and MPO (r=0.437, P=0.018) and TOS and CLP (r=0.409, P=0.028) at disease onset, whereas a negative correlation was found between MPO and thiol (r=-0.597, P=0.001) during remission. In conclusion, protein oxidation and neutrophil activation may play important roles in the pathogenesis of HSP. Further research is required to understand the potential linkage between oxidant stress and complications and to develop therapeutic strategies in HSP.
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    Paraoxonase, total antioxidant activity and peroxide levels in marasmic children
    (Pergamon-Elsevier Science Ltd, 2007) Ece, Aydın; Gurkan, Fuat; Celik, Fatma; Boşnak, Mehmet; Yel, Servet; Balik, Hasan; Erel, Ozcan
    Objectives: The aim of this study was to investigate the oxidant/antioxidant status, paraoxonase (PON) activity and leptin. levels in children with marasmic malnutrition. Design and methods: Thirty marasmic children (age 14.4 +/- 10.3. months) and 28 control subjects were included; Plasma PON activity, total antioxidant activity (TAO), total peroxide (TPX) and leptin,levels were measured. Results: Malnourished children had significantly. lower leptin.(3.6 +/- 1.1. vs. 11.8 +/- 4.5 ng/mL, P < 0.001), PON. activity (66.4 +/- 28.6 vs. 2213 +/- 31.6 IU/L, P < 0.001) and. TAO (1.44 +/- 0.12 vs. 2.45 +/- 0.61 mmol Trolox equiv/L, P < 0.001); and higher TPX (15.6 +/- 6.4 vs. 5.9 +/- 1.9 mu mol/L, P < 0.001) values than,in controls. Significant negative correlation was found between PON and TPX (P=0.040) and positive correlation between TAO and BMI (P= 0.034) in patients. No significant correlation was found between leptin and oxidam/antioxidant parameters (P > 0.05). Conclusions: Children with marasmic. malnutrition had increased. pro-oxidant and decreased antioxidant status. Extent of oxidative stress increases with malnutrition severity.. Antioxidants could be given during nutritional rehabilitation., (c) 2007 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.