Aykan Yücel

Serum paraoxonase 1 activity, asymmetric dimethylarginine levels, and brachial artery flow-mediated dilatation in women with polycystic ovary syndrome

OBJECTIVE To evaluate endothelial function via serum asymmetric dimethylarginine (ADMA) levels, paraoxonase 1 (PON1) activity, and brachial artery flow-mediated dilatation (FMD) in women with polycystic ovary syndrome (PCOS). DESIGN Prospective case-control study. SETTING University hospital. PATIENT(S) Thirty patients with PCOS with a mean age of 24.33 ± 4.50 years and 30 healthy controls matched for body mass index (BMI) and age. INTERVENTION(S) Endothelial function was assessed biochemically with serum ADMA levels and serum PON1 activity and functionally with brachial artery FMD by ultrasonography. MAIN OUTCOME MEASURE(S) Serum ADMA levels, serum PON1 activity, brachial artery FMD, hormonal and biochemical parameters. RESULT(S) Patients with PCOS had higher levels of free testosterone and insulin, and higher waist-hip ratio and Ferriman Gallwey scores when compared with the controls. Fasting glucose and homeostasis model assessment of insulin resistance were not different between the groups. There was no statistically significant difference in ADMA levels between two groups. Serum PON1 activity and brachial artery FMD were statistically significantly lower in women with PCOS. There was negative correlation between ADMA and PON1 in patients with PCOS. CONCLUSION(S) Serum PON1 activity and brachial artery FMD, as markers of endothelial dysfunction and cardiovascular risk, were statistically significantly lower in women with PCOS compared with healthy controls matched for age and BMI. Endothelial dysfunction may be seen at earlier ages in patients with PCOS.

The effects of oral contraceptives including low-dose estrogen and drospirenone on the concentration of leptin and ghrelin in polycystic ovary syndrome.

OBJECTIVE To evaluate short-term leptin and ghrelin concentrations in women with polycystic ovary syndrome (PCOS) who use low-dose oral contraceptives containing drospirenone. DESIGN Prospective study. SETTING Department of obstetrics and gynaecology in a university hospital. PATIENT(S) Twenty women with PCOS were enrolled in the study. INTERVENTION(S) A low-dose oral contraceptive containing ethinyl estradiol and drospirenone was given for three cycles. MAIN OUTCOME MEASURE(S) Serum androstenedione, free T, T, dehydroepiandrosterone sulphate, sex hormone-binding globulin, FSH, LH, E(2), lipid profiles, leptin, and ghrelin levels were measured in each subject. Insulin resistance was estimated by the homeostasis model assessment-insulin resistance (HOMA-IR). RESULT(S) While leptin concentrations did not change with therapy, ghrelin levels increased statistically. Baseline leptin concentrations were correlated positively with body mass index, waist-to-hip ratio, insulin, and HOMA-IR and negatively with ghrelin. After controlling for body mass index and waist-to-hip ratio in a partial correlation analysis, leptin levels were not correlated with these parameters. Ghrelin was inversely correlated with body mass index, waist-to-hip ratio, insulin, HOMA-IR, and free T. CONCLUSION(S) In patients with PCOS, an oral contraceptive containing ethinyl estradiol and drospirenone increases ghrelin levels but not leptin levels in a 3-month period. Ghrelin might be related to the metabolic and androgenic changes in patients with PCOS.

The association of androgenic sex steroids with serum lipid levels in postmenopausal women

Background.  The aim of the present study was to examine the correlations between androgenic sex steroids and serum lipid levels in postmenopausal women.

Change in retrobulbar circulation during menstrual cycle assessed by doppler ultrasound

Our purpose was to study the hemodynamic changes in the ophthalmic, central retinal and posterior ciliary arteries during the normal menstrual cycle and to relate the vascular changes to menstrual cycle. A total of 23 healthy women underwent serial color Doppler ultrasonography at least six times during a normal menstrual cycle, twice each in follicular, ovulatory and luteal phases. Pulsatility and resistance index and peak systolic velocity of the each arteries were assessed with color Doppler imaging. There was no statistical difference in any of the parameters during the menstrual cycle. This was supposed to be because generalized hormonal effects on heart rate, blood pressure, blood volume, cardiac output and on the diameter of the vessel cancel each other and this effect maintains the same ocular blood flow and perfusion during the menstrual cycle.

Plasma apelin levels in patients with polycystic ovary syndrome.

OBJECTIVE The aim of the study was to evaluate plasma apelin levels in patients with polycystic ovary syndrome (PCOS) and healthy controls. MATERIAL AND METHODS Plasma apelin levels, serum lipid levels, serum hormone levels, and homeostasis model assessment-insulin resistance (HOMA-IR) values of 32 patients with PCOS and 31 healthy women forming the control group were checked. RESULTS Plasma apelin levels of the PCOS group (0.350±0.083 ng/ml) were significantly higher than those of the control group (0.246±0.045 ng/ml) (p<0.001). No significant correlation was detected between apelin levels and biochemical or clinical data in PCOS group. CONCLUSION Plasma apelin levels were significantly higher in PCOS patients.

Plasma lipocalin‐2 levels in pregnancy

Objective. To evaluate plasma levels of lipocalin‐2, which is a novel adipokine associated with obesity and insulin resistance, in pregnant women. Design. Prospective case–control study. Setting. University hospital. Population. Pregnant women with pre‐pregnancy body mass index >25kg/m2 (overweight; n=29) and body mass index <25kg/m2 (n=27), whose gestational ages were between 24 and 28weeks, as study groups and nonpregnant control women with body mass index <25kg/m2 (n=29). Methods. Plasma lipocalin‐2 levels, fasting plasma glucose and fasting plasma insulin levels; homeostasis model assessment insulin resistance index and fasting plasma glucose/fasting plasma insulin ratio were measured for each subject. Main Outcome Measures. Comparisons among the groups and correlations for lipocalin‐2 and the parameters of insulin resistance. Results. Plasma lipocalin‐2 levels among the pregnant women were significantly higher than those of the control group (p<0.001 for both group comparisons). Lipocalin‐2 levels were significantly higher in the group with pre‐pregnancy body mass index >25kg/m2 compared with the group with pre‐pregnancy body mass index <25kg/m2 (p=0.003). Lipocalin‐2 levels were positively correlated with homeostasis model assessment insulin resistance index and fasting plasma insulin and negatively correlated with fasting plasma glucose/fasting plasma insulin ratio in both pregnant groups. Conclusions. Lipocalin‐2 was found to be higher in pregnant women, especially when pre‐pregnancy body mass index was >25kg/m2, and it was correlated with markers of insulin resistance.

An alternative method for measuring oxidative stress in intrahepatic cholestasis of pregnancy: thiol/disulphide homeostasis

Abstract Purpose: The aim of our study was to evaluate the oxidative stress (OS) in pregnant women with intrahepatic cholestasis of pregnancy (ICP) by evaluating thiol/disulphide homeostasis using an alternative technique. Methods: A total of 57 pregnant women with ICP were compared with 50 gestational age and body mass index matched controls. A recently defined method was used for the measurement of plasma native-total thiol and disulphide levels. The independent two-sample t test, Mann–Whitney-U test, Chi-square test, binary logistic regression with backward elimination and receiver operating characteristic (ROC) curve was performed for statistical analyses. Results: Pregnant women with ICP (n = 57) versus controls (n = 50) had significantly lower serum levels of native thiol (233.8 ± 47.4 μmol/L vs. 308.5 ± 51.7 μmol/L, p < .001), total thiol (258.4 ± 46.5 μmol/L vs. 328.0 ± 52.0 μmol/L, p < .001) and higher levels of disulphide (12.3 ± 3.6 μmol/L vs. 9.7 ± 3.4 μmol/L, p < .001). Binary logistic regression showed that the most important variables related to ICP were native thiol and total thiol. According to the ROC curve, the optimal cut-off level for native thiol was 280.0 μmol/L (sensitivity: 86%, specificity: 84.2%, area under the curve (AUC):0.896, 95% CI: 0.831–0.962, p < .001), and the optimal cut-off level for total thiol was 300.0 μmol/L (sensitivity: 86%, specificity: 80.7%, AUC: 0.883, 95% CI: 0.815–0.951, p < .001). Conclusions: To our knowledge, this is the first study in the literature exploring thiol/disulphide balance in ICP. We found that thiol/disulphide balance indicate OS in pregnant woman with ICP.

Effects of l-carnitine on oxidative stress parameters in oophorectomized rats

Abstract Aims The aim of this study was to investigate the antioxidant effects of l-carnitine on the oxidative stress parameters in oophorectomized rats. Methods Twenty-four female albino Wistar rats were used. Rats were divided into four groups: laparotomy-only (LOSALINE) group, oophorectomy plus l-carnitine 100 mg/kg/day (OXL100) group, oophorectomy plus l-carnitine 500 mg/kg/day (OXL500) group, and oophorectomy-only (OXSALINE) group. Experimental protocol was started on day 21 post-castration. Various dosage forms of l-carnitine or isotonic saline were administered intraperitoneally for 14 consecutive days. Nitric oxide (NO), malondialdehyde (MDA), total antioxidant status (TAS), total oxidative stress (TOS) and oxidative stress index (OSI) were evaluated in the tissues including kidney, liver and heart, and sera. Result(s) In the heart tissue samples, there was no difference in the levels of NO, OSI and TOS between the groups. However, MDA levels in OXSALINE group were significantly higher than OXL500 group. On the other hand, there was no statistically significant differences between the groups in terms of levels of NO, MDA, TAS, TOS and OSI in liver, kidney and sera samples. Conclusion(s) Levels of MDA in the heart tissue were significantly higher in OXSALINE group compared to OXL500 group. Thus, it may be suggested that l-carnitine reduces oxidative stress at least in the heart of oophorectomized rats.

Urinary Neopterin Levels in the Different Stages of Pregnancy

Background/Aims: Neopterin is a biochemical marker of activated cell-mediated immune response which increases in pathological conditions associated with cellular immune activation as well as in pregnancy where cellular immune response is predominant. The aim of this study was to determine the urinary neopterin level in each trimester of pregnancy and to determine if it can be used as a marker. Methods: 104 healthy pregnant women (mean age 22.10 ± 4.39 years; 36 in the first, 30 in the second and 38 in the third trimester) and 16 non-pregnant healthy women (mean age 20.94 ± 4.48 year) were included. Results: The mean urinary neopterin concentration of all pregnant women was higher than that of non-pregnant women (166.4 ± 31.7 and 103.1 ± 27.5 µmol/mol creatinine respectively, p < 0.01). The mean urinary neopterin levels in each trimester and non-pregnant women were 139.8 ± 49.6, 131 ± 40.2, 227.9 ± 86.5 and 103.1 ± 27.5 µmol/mol creatinine, respectively. Urinary neopterin levels were not significantly different between non-pregnant, first and second trimester groups, but were significantly higher in the third trimester than each of these groups (p < 0.05, p < 0.01 and p < 0.01 respectively). Conclusion: Urinary neopterin levels increase significantly in the third trimester probably due to more predominated cellular immunity. The pathologies causing cellular immune activation, especially in the first two trimesters can be predicted with urinary neopterin levels.

Low serum vitamin D level is associated with intrahepatic cholestasis of pregnancy

Intrahepatic cholestasis of pregnancy (ICP) is a unique hepatic disorder of pregnancy and is related to adverse maternal and perinatal outcomes. The pathogenesis of the disease is not clear and appears to be multifactorial. There is increasing evidence that vitamin D (Vit D) plays a role in hepatobiliary homeostasis and in various liver diseases. We aimed to investigate the association between serum Vit D level and ICP.