Harun Toy

Serum paraoxonase and arylesterase activities in patients with epithelial ovarian cancer

OBJECTIVE The HDL-associated paraoxonase and arylesterase activities play a role in decreasing oxidative stress, which is known to contribute to cancer development. The aim of this study was to evaluate serum paraoxonase and arylesterase activities and lipid hydroperoxide (LOOH) levels in patients with newly-diagnosed epithelial ovarian cancer. MATERIALS Serum paraoxonase and arylesterase activities, total free sulfhydryl (-SH) levels and LOOH levels were measured in patients with epithelial ovarian cancer (n=24) and controls (n=29). RESULTS Serum paraoxonase activity and arylesterase activity, as well as -SH levels were significantly lower (p=0.003, p<0.001 and p<0.001, respectively) in patients with epithelial ovarian cancer compared to controls, while LOOH levels were significantly higher (p<0.001). A significant inverse correlation was found between the stage, grade and CA-125 level of ovarian cancer and paraoxonase activity (rho=-0.630, p=0.001 and rho=-0.601, p=0.002 and rho=-0.436, p=0.033, respectively), arylesterase activity (rho=-0.601, p=0.002 and rho=-0.713, p<0.001 and rho=-0.580, p=0.003, respectively), and -SH levels (rho=-0.642, p=0.001 and rho=-0.637, p=0.001 and rho=-0.530, p=0.008, respectively). In contrast, there was a positive correlation between LOOH and the stage, grade and CA-125 level of ovarian cancer (rho=0.565, p=0.004 and rho=0.479, p=0.018 and rho=0.642, p=0.001). CONCLUSION Our results suggest that diminished paraoxonase and arylesterase activity, -SH levels and increased LOOH levels are associated with particular stage, grade and CA-125 level of ovarian cancer.

Serum prolidase activity and oxidative stress markers in pregnancies with intrauterine growth restricted infants

Aim:  To compare the levels of serum prolidase activity and oxidative stress markers, including total oxidative status (TOS), total antioxidant capacity (TAC), oxidative stress index (OSI), and total free sulfhydryl (–SH) in healthy pregnant women and pregnant women with intrauterine growth restricted infants.

Assessment of preoperative serum prolidase activity in epithelial ovarian cancer

OBJECTIVE Prolidase is a cytosolic exopeptidase that cleaves iminodipeptides with C-terminal proline and hydroxyproline and plays a major role in collagen turnover. The aim of this study was to evaluate preoperative serum prolidase activity, total oxidant status (TOS), and total antioxidant capacity (TAC) in patients with newly diagnosed epithelial ovarian cancer (EOC). STUDY DESIGN Serum prolidase activity, TOS, and TAC were measured spectrophotometrically in both EOC cases (n=28) and controls (n=28). RESULTS Preoperative serum prolidase activity and TOS were significantly higher in patients with EOC compared to controls (p=0.009 and 0.008, respectively), whereas TAC was significantly lower in cases (p<0.001). A significant positive correlation was found between the stage, grade, and CA-125 level of EOC and serum prolidase activity (rho=0.466, p=0.012; rho=0.501, p=0.007; and rho=0.447, p=0.017, respectively) and TOS (rho=0.588, p=0.001; rho=0.412, p=0.029; and rho=0.568, p=0.002, respectively). In contrast, there was a negative correlation between TAC and the stage, grade, and CA-125 level of EOC (rho=-0.555, p=0.002; rho=-0.566, p=0.002; and rho=-0.581, p=0.001, respectively). CONCLUSION Findings of the present study demonstrate that serum prolidase activity is significantly associated with the stage, tumor grade, and preoperative CA-125 level of EOC.

Serum prolidase activity and oxidative status in patients with stage I endometrial cancer.

Introduction: We aimed to investigate the serum prolidase activity, total oxidant status (TOS), total antioxidant capacity (TAC), and total free sulfhydryl (-SH) groups in patients with stage I endometrial cancer. Methods: Serum prolidase activity, TOS, TAC, and -SH levels were measured in patients with endometrial cancer (n = 23) and controls (n = 25). Results: Serum prolidase activity and TOS were significantly higher in patients with endometrial cancer than in controls (P = 0.02 and P = 0.02, respectively), whereas TAC and -SH group levels were significantly lower (P = 0.004 and P = 0.001, respectively). There were no differences between surgical stages IA and IB or between stages IB and IC (P = 0.189 and P = 0.161, respectively) with respect to prolidase levels, whereas there was a significant difference between stages IA and IC (P < 0.001). Conclusions: Increased serum prolidase activity and oxidative stress may be associated with endometrial cancer, and increased serum prolidase activity may be related to local invasion of endometrial cancer.

Decreased Serum Prolidase Activity and Increased Oxidative Stress in Early Pregnancy Loss

Aims: To compare the levels of serum prolidase activity and oxidative stress markers including total oxidative status (TOS), total antioxidant capacity (TAC), lipid hydroperoxide (LOOH) and total free sulfhydryl (–SH) in healthy pregnant women without early pregnancy loss (EPL) and women with EPL. Methods: Serum samples were obtained from 45 healthy first-trimester pregnancies and 45 pregnancies complicated with EPL. We have measured serum prolidase activity, TAC, TOS, –SH and LOOH levels spectrophotometrically. Results: Serum prolidase, TAC and –SH levels were significantly lower in the women with EPL than in the women without EPL (p <0.001, p = 0.001, p < 0.001, respectively), whereas TOS and LOOH levels were significantly higher (p < 0.001, p = 0.004, respectively). Prolidase activity was negatively correlated with TOS and LOOH levels (r = –0.299, p = 0.004; r = –0.323, p = 0.002, respectively), while positively correlated with TAC and –SH levels (r = 0.232, p = 0.028, and r = 0.418, p <0.001, respectively) Conclusion: Findings of this study have shown that serum prolidase activity and oxidative stress are significantly associated with the presence of EPL, and the correlation between serum prolidase activity and the markers of oxidative stress was reflected in increased serum TOS and LOOH levels and decreased serum TAC and –SH levels.

Internal iliac artery ligation for severe postpartum hemorrhage and severe hemorrhage after postpartum hysterectomy

Aim:  The aim of this study was to evaluate the effect of internal iliac artery (IIA) ligation performed for severe postpartum hemorrhage (PPH).

Decreased Paraoxonase and Arylesterase Activities in the Pathogenesis of Future Atherosclerotic Heart Disease in Women with Gestational Diabetes Mellitus

OBJECTIVE The aim of this study was to investigate serum paraoxonase, arlyesterase activities, and lipid hydroperoxide (LOOH) levels in patients with gestational diabetes mellitus (GDM). METHODS Paraoxonase and arylesterase activities, and LOOH levels were assessed for GDM cases (n = 55) and controls (n = 59). Serum basal and salt-stimulated paraoxonase and arylesterase activities were measured spectrophotometrically. LOOH levels were measured by ferrous oxidation with a xylenol orange assay. RESULTS Basal and salt-stimulated paraoxonase and arylesterase activities were significantly lower (p = 0.002, p = 0.004; and p = 0.013, respectively) in patients with GDM compared to controls, while LOOH levels were significantly higher (p < 0.001). Among gestational diabetes patients, serum paraoxonase and arylesterase activities were inversely correlated with LOOH levels (r = - 0.390, p = 0.003; and r = - 0.287, p = 0.034, respectively). CONCLUSIONS Findings of the present study have shown that serum paraoxonase and arylesterase activities are significantly reduced in women with GDM. Decreased serum paraoxonase and arylesterase activities might play a role in the potential early pathogenesis for atherosclerotic heart disease in GDM beyond their antioxidant properties.

Amniotic Fluid Prolidase Activity and Oxidative Status in Neural Tube Defects

Objective: To evaluate oxidative stress markers and prolidase activity in the amniotic fluid of fetuses with a neural tube defect (NTD) compared to the amniotic fluid of normal fetuses. Methods: Amniotic fluid samples from 36 pregnancies of fetuses with NTD were compared with the amniotic fluid from 36 pregnancies of genetically normal fetuses for analysis of oxidative status and prolidase activity. The control group consisted of fetuses from pregnancies that were diagnosed as high-risk according to a 1st or 2nd trimester aneuploidy screening, but which were later confirmed to have normal results. An automated method was used to measure oxidative status. Prolidase enzyme activity was determined using a photometric method. Results: Prolidase activity, total oxidant status and oxidative stress index of amniotic fluid from fetuses with NTD were significantly higher compared to controls (p < 0.001, p = 0.003 and p = 0.002, respectively), whereas total antioxidant capacity was significantly lower (p < 0.001). Conclusion: Levels of prolidase activity and oxidative stress are increased in the amniotic fluid of fetuses with NTD. These indicators may serve as diagnostic markers in this disease.

Oxidative stress and prolidase activity in women with uterine fibroids

The aim of this study was to investigate oxidative stress markers and prolidase activity in serum and tissue samples of women with uterine fibroids, with further analysis on position and size. Lipid hydroperoxide, ceruloplasmin, catalase, arylesterase, free sulfhydryl group activity and prolidase activity levels were measured in fibroid tissue, myometrial tissue and serum of the same patients (n = 51), at the same time. Results show that ceruloplasmin, catalase, arylesterase, free sulfhydryl group and prolidase activities were higher in fibroid tissue than those in myometrial tissue (p = 0.003, 0.009, 0.004, 0.02, 0.008, respectively). Serum levels of catalase and prolidase were lower, and arylesterase and free sulfhydryl groups were higher in the fibroid group than those in the control group (p < 0.001 for all). Fibroid volume in submucosal subgroup of the fibroid group yield significant correlation with ceruloplasmin, catalase, arylesterase and prolidase activities (r = 0.84, p = 0.02; r = 0.93, p < 0.001; r = 0.63, p = 0.049 and r = 0.87, p = 0.01, respectively). Despite the lack of statistical significance, the highest levels of prolidase activity were found in fibroid samples, especially in submucosal ones. It is concluded that this study demonstrated increased antioxidative repair system in the fibroid tissue compared to the myometrium and serum of the same patients. Additionally, higher pathophysiological potential of the submucosal fibroids over intramural and subserosal fibroids were shown with the levels of oxidative stress markers and prolidase activity levels.

Evaluation of the Future Atherosclerotic Heart Disease with Oxidative Stress and Carotid Artery Intima Media Thickness in Gestational Diabetes Mellitus

Background and objective. In this study our aim was to evaluate paraoxonase (PON1) activity and free sulfhydryl groups (–SH) as antioxidative parameters and lipid hydroperoxide (LOOH) as oxidative parameter in the serum of women with gestational diabetes mellitus (GDM) and determine their relation with the degree of subclinical atherosclerosis. Material and methods. Serum samples from 39 pregnant women complicated with GDM and 40 healthy pregnant women were collected for the analysis of oxidative markers. Common carotid artery intima media thickness (CIMT) was measured for both groups to assess future atherosclerotic heart disease risk. PON1 activity and –SH were measured spectrophotometrically. LOOH levels were measured by ferrous oxidation with a xylenol orange assay. Results. CIMT and LOOH levels were significantly higher (p = 0.01, p < 0.001, respectively) in GDM group compared to controls, whereas PON1 and –SH levels were significantly lower (p < 0.001 for both). CIMT values were significantly correlated with body mass index (BMI), 50 g oral glucose tolerance test (OGTT), and mean arterial blood pressure (MABP) (p = 0.003, p = 0.02, and p = 0.03, respectively). However, there was no correlation between CIMT and oxidative markers. Conclusions. Increased levels of LOOH and decreased levels of PON1 and –SH showed disturbance of antioxidative mechanisms in GDM. These changes were associated with increased BMI and MABP which may be relevant to GDM pathophysiology. Furthermore, increased CIMT values in GDM compared to healthy controls designate increased risk of future atherosclerotic heart disease.