Hülya Aksoy

Erythrocyte superoxide dismutase and glutathione peroxidase activities, and malondialdehyde and reduced glutathione levels in schizophrenic patients

Abstract There is abundant evidence that free radicals are involved in membrane pathology in the central nervous system and that they may play a role in neuropsychiatric disorders, including schizophrenia. In this study, we investigated erythrocyte superoxide dismutase and glutathione peroxidase activities as antioxidant enzymes, malondialdehydes as a sign of lipid peroxidation, and reduced glutathione levels in schizophrenic patients. Activities of superoxide dismutase and levels of malondialdehyde in erythrocytes were greater in all patients (n=48) and in patients with acute (n=16) and chronic schizophrenia (n=32) (p<0.001 for all patients and chronic patient group; p<0.05 for acute patient group). The activities of glutathione peroxidase were lower in patients (p<0.05 for all patients and acute patient group; p=0.051 for chronic patient group) compared with the control group. Mean erythrocyte reduced glutathione was lower in patients than in controls (p<0.05). In the patient group, erythrocyte superoxide dismutase activity was positively correlated with scales and duration of disease and erythrocyte malondialdehyde concentration. These data reveal that antioxidative defense mechanisms might be impaired in schizophrenic patients.

Serum 1,25 dihydroxy vitamin D (1,25(OH)2D3), 25 hydroxy vitamin D (25(OH)D) and parathormone levels in diabetic retinopathy.

OBJECTIVES To investigate whether there is a relationship between serum 1,25 dihydroxy vitamin D3 [1,25(OH)2D3], which is an inhibitor of angiogenesis, concentrations and severity of diabetic retinopathy (DR). DESIGN AND METHODS Serum 1,25(OH)2D3, 25 hydroxy vitamin D [25(OH)D] and parathormone (PTH) concentrations were measured in diabetic patients (n = 66) and nondiabetic healthy subjects (n = 20). RESULTS The mean serum 1,25(OH)2D3 concentration in diabetic patients was lower than that in nondiabetics (57.3+/-21.44 vs. 89.4+/-18.01 pmol/L, p<0.001); mean 1,25(OH)2D3 concentrations fell with increasing severity of DR [being 63.4+/-17.26 pmol/L for background DR (BDR), 47.7+/-13.27 pmol/L for preproliferative DR (pre-PDR), and 43.1+/-19.45 pmol/L for proliferative DR (PDR)]. Compared with the control group, serum 25(OH)D concentrations were found to be decreased in diabetic patients (p<0.001). There were negative correlations between 1,25(OH)2D3 and age (r = -0.331, p<0.01) and duration of diabetes (r = -0.255, p<0.05). CONCLUSION From these findings, it was found that there was an inverse relationship between the severity of the retinopathy, i.e., neovascularization, and serum 1,25(OH)2D3 concentrations, being the lowest in PDR and the highest in diabetic patients without retinopathy (NDR) patients. The measurement of serum 1,25(OH)2D3 concentrations might be helpful to predict severity of DR in patients with diabetes mellitus.

The changes of superoxide dismutase, catalase and glutathione peroxidase activities in erythrocytes of active and passive smokers.

Abstract Cigarette smoking has been implicated in the pathogenesis of ischemic heart disease, emphysema, obstructive lung disease and neoplastic disorders. More than 1000 constituents of smoke, including many oxidants, pro-oxidants, free radicals and reducing agents, have been identified. The activities of erythrocyte superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), which are the important components of antioxidant defense system, were measured in 100 healthy volunteers. This study included heavy smokers (consuming cigarettes ≥20 per day; n=30, group I), light smokers (consuming cigarettes< 20 per day; n=30, group II), passive smokers (exposed to cigarette smoke in the indoor environment; n=20, group III), and non-smokers (n=20, the control group). While activities of SOD and CAT in erythrocytes were significantly lower in groups I, II and III than in the control group (p<0.01 for all), mean erythrocyte GSH-Px activity in group III was higher than that in groups I, II and in controls. These results suggest that the increased oxidative stress occurs in smokers, owing to the free radicals present in smoke. It might cause a decrease in antioxidant enzyme activities and oxidant/antioxidant imbalance. We also observed that passive smokers were affected by the environmental smoke to the same extent as active smokers.

Maternal Serum Interleukin-10, Interleukin-2 and Interleukin-6 in Pre-Eclampsia and Eclampsia

The aim of the study was to investigate and compare the concentrations of interleukin (IL)‐2, IL‐6, and IL‐10 in serum of women with mild pre‐eclampsia, severe pre‐eclampsia, eclampsia, and normotensive pregnancy.

Serum lipid profile paraoxonase and arylesterase activities in psoriasis.

Psoriasis is a common chronic and recurrent inflammatory skin disease with unknown etiology that has been associated with abnormal plasma lipid metabolism and oxidative stress. There are controversial results in the previous studies investigating oxidant/antioxidant systems in psoriasis.

The relationship between varicocele and semen nitric oxide concentrations

Abstract We investigated the relationship between seminal plasma nitric oxide (NO) concentrations and conventional semen parameters in patients with varicocele. Semen samples were obtained from infertile patients with varicocele (n=55) and from normal controls (n=48). The mean NO concentration in the seminal plasma of patients with varicocele was significantly higher than that of the controls (P < 0.01). A significant negative correlation was noted between NO and sperm motility (r=−0.29, P=0.003), NO and sperm concentration (r=−0.26, P=0.008) and NO and normal morphology (normal %) (r=−0.25, P=0.01). It was concluded that increased NO production may influence sperm production, motility and morphology in patients with varicocele.

Protective effects of melatonin against myocardial injury induced by isoproterenol in rats.

Abstract: This study was performed to determine whether melatonin could have a protective effect against myocardial injury (MI) induced by isoproterenol (ISO) in rats. Twenty‐four rats were divided into three treatment groups: (1) control (n = 8): saline solution. (2) ISO (n = 8): ISO only. (3) melatonin + ISO (n = 8). Melatonin (10 mg/kg/day, i.p.) was administered 30 min before the initiation of ISO (150 mg/kg/day, s.c.). Drugs and saline were given at 14:00 hr for two consecutive days. At the end of the second day, blood samples were taken from the abdominal aorta shortly after the rats were anesthetized for the purpose of measuring cardiac troponins T (cTnT) and I (cTnI); hearts were removed, preserved and examined microscopically. Additionally, based on the histological changes in myocardial tissue, the rats were divided into three groups: no change, mild changes and moderate and/or marked changes. The mean cTnT and cTnI values were significantly increased in ISO group compared with control group [(1.29 ± 0.22 ng/mL versus 0.46 ± 0.07 ng/mL, P < 0.0001) and (0.56 ± 0.11 ng/mL versus 0.21 ± 0.01 ng/mL, P < 0.001)], respectively, and were significantly reduced in the ISO + melatonin group (0.65 ± 0.06 ng/mL for cTnT and 0.25 ± 0.01 ng/mL for cTnI) compared with the ISO only group (P < 0.01), respectively. cTnT and cTnI values were significantly increased in rats with moderate and/or marked cardiac changes compared with hearts where there were mild changes and no change (P < 0.05). ISO + melatonin group showed less histological changes than the ISO group (P < 0.01). In conclusion, this study revealed a protective effect of melatonin against ISO‐induced MI in rats, and its potential clinical application in the treatment of MI.

Correlation of P-selectin and lipoprotein(a), and other lipid parameters in preeclampsia

Abstract Preeclampsia is a pregnancy specific disorder and is thought to be associated with generalized endothelial dysfunction. P-selectin, an adhesion molecule, mediates the interaction of monocytes, platelets, and endothelial cells. Increased P-selectin levels and altered lipid and lipoprotein metabolism were reported in preeclampsia and during pregnancy. In order to investigate the relationship between serum P-selectin and lipoprotein(a), and other lipid parameters, 28 preeclampsia [13 severe (group I) and 15 mild preeclampsia (group II), 15 healthy pregnant (group III) and 20 non-pregnant (group IV)] women were investigated. Serum P-selectin, lipoprotein(a), total cholesterol, triglyceride, and high density lipoprotein cholesterol were measured and low-density lipoprotein cholesterol was derived. Serum P-selectin concentrations were consistently and significantly higher in the severe preeclampsia group than in the mild preeclampsia, healthy pregnancy, and non-pregnant control groups (P<0.0001, for all). The mild preeclampsia group also had increased serum P-selectin concentrations compared with the healthy pregnancy group and non-pregnant controls (P<0.05 and P<0.0001, respectively). Serum P-selectin and lipoprotein(a) levels revealed a significant and linear increase with the severity of preeclampsia. There were also significant (in groups I and II) and borderline (in groups III and IV) correlations between P-selectin and total cholesterol. The present study suggests that P-selectin may be an additional risk marker for preeclampsia, and may be useful in distinguishing women with mild and severe preeclampsia and normal pregnancy.

Antioxidant Potential and Transferrin, Ceruloplasmin, and Lipid Peroxidation Levels in Women with Preeclampsia

Background The aim of this study was to evaluate lipid peroxidation and antioxidant function in patients with preeclampsia and in normotensive pregnant women and to assess an association with the severity of the disease. Methods Twenty-one patients with mild preeclampsia, 15 patients with severe preeclampsia, and 19 normotensive pregnant women were included in the study. Plasma antioxidant potential (AOP) status, ceruloplasmin (Cp) and transferrin (Trf) levels as antioxidants, and malondialdehyde (MDA) levels as an indicator of lipid peroxidation were measured. Results Whereas the AOP and Trf levels of the severe and mild preeclampsia groups were found to be reduced, the MDA and Cp levels were increased compared with those of the normotensive pregnant group. There were statistically significant negative correlations between AOP and MDA in all groups. No differences were observed between the groups with severe and mild preeclampsia with respect to these analytes. Conclusion Our findings suggest that lipid peroxidation may be an important factor in the pathogenesis of preeclampsia and that plasma antioxidants and oxidants are altered in preeclampsia. However, these findings may not be useful in distinguishing women with severe and mild preeclampsia.

Dehydroepiandrosterone prevents oxidative injury in obstructive jaundice in rats.

We investigated the effect of dehydroepiandrosterone (DHEA) on oxidative injury in obstructive jaundice using three groups of rats: sham-operated group; common bile duct (CBD) group — the CBD was ligated; and DHEA group — DHEA administration followed CBD ligation. Liver function tests were performed using blood samples, and malondialdehyde concentration (MDA), superoxide dismutase activities (SOD), glutathione peroxidase (GPx), and total glutathione (tGSH) concentrations were measured in liver tissue. Serum alkaline phosphatase, γ-glutamyltransferase and alanine aminotransferase activity were significantly elevated in the CBD group compared with the other groups. Serum aspartate aminotransferase and total bilirubin were highest in the CBD group; the MDA concentration was higher in the CBD group than the sham group. There were no significant differences in GPx activity among the groups. SOD activity and tGSH concentration were significantly lower in the CBD group than the other groups. DHEA may protect hepatic tissue against oxidative injury in obstructive jaundice by decreasing MDA concentration and increasing SOD activity and tGSH concentration.