Fatih Akcay

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 Oxidant/Antioxidant Status of Patients with Systemic Lupus Erythematosus

Abstract The levels of malondialdehyde and ceruloplasmin, and superoxide dismutase activity were higher, while transferrin concentration and the activities of glutathione peroxidase and catalase were lower in serum of patients with systemic lupus erythematosus (n=24) compared with healthy controls (n=20). Disease activity index correlated positively with serum malondialdehyde level (r=0.47, p<0.05), erythrocyte sedimentation rate (r=0.41, p<0.05) and C-reactive protein concentration (r=0.41, p<0.05), while it correlated negatively with serum superoxide dismutase (r=0.42, p<0.05) and glutathione peroxidase (r= −0.44, p<0.05) activities in patients. No such correlations were found in healthy control subjects. It remains to be seen whether correlations found between disease activity score and serum malondialdehyde level, and also activities of serum superoxide dismutase and glutathione peroxidase enzymes observed in the present study may be used to predict prognosis in patients with systemic lupus erythematosus.

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.

Malondialdehyde and Nitric Oxide Levels in the Plasma of Patients with Advanced Laryngeal Cancer

AbstractPurpose. We investigated alterations in plasma nitrite, nitrate, total nitric oxide (NO•), and malondialdehyde (MDA) levels in patients with advanced stage laryngeal cancer. Methods. We measured the levels of MDA and total NO−2, as well as the NO−3 marker for NO• generation, in 25 patients with advanced laryngeal cancer and 15 healthy control subjects. Results. The levels of plasma MDA, NO•, and NO−3 were significantly higher in the patients with laryngeal cancer than in the healthy controls (P ≪ 0.001 for all). On the other hand, although plasma NO−2 was increased in the patient group, the statistical difference was not significant (P ≫ 0.05). Moreover, the MDA and NO• levels did not differ significantly between patients with stage III and stage IV laryngeal cancer. Conclusion. These findings demonstrate that oxidative stress is increased in patients with advanced laryngeal cancer.

Bone mineral density in children with cerebral palsy.

Abstract Background : The purpose of the present study was to evaluate the severity of and factors related to osteopenia in children with cerebral palsy (CP).

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.

Effects of aqueous extracts of Satureja hortensis L. on rhinosinusitis treatment in rabbit.

Satureja hortensis L. (Lamiaceae) is an annual herb that used as traditional folk medicine in Eastern Anatolia region of Turkey for treatment of different infectious diseases and disorders. This study was designated to investigate anti-inflammatory effect of aqueous extract (250 mg/kg) of Satureja hortensis. Therapeutic potential of Satureja hortensis as an anti-inflammatory agent was examined by measurement of NO* metabolites and histological changes in a rabbit model of rhinosinusitis. The results showed that both activity of NOS enzyme and concentration of NO* metabolites were significantly reduced by topical administration of Satureja hortensis extract. Histological examination demonstrated no edema and/or reduced inflammation in therapy group as compared to the control. Thus, the data suggest Satureja hortensis extract may have the potential to be used as anti-inflammation agent, and can be used in the treatment of rhinosinusitis diseases.

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.

Oxidative stress in infants born to preeclamptic mothers

Abstract Background : Oxidative stress may play an important role in the pathophysiology of preeclampsia. An increase in lipid peroxidation products and a decrease in antioxidant activity in preeclamptic women have been reported in many papers. The objective of this study was to evaluate oxidative stress in infants born to preeclamptic mothers.

Vitamin D supplementation blocks pulmonary structural and functional changes in a rat model of perinatal vitamin D deficiency

Whereas epidemiological data strongly link vitamin D (VD) deficiency to childhood asthma, the underlying molecular mechanisms remain unknown. Although VD is known to stimulate alveolar epithelial-mesenchymal interactions, promoting perinatal lung maturation, whether VD supplementation during this period protects against childhood asthma has not been demonstrated experimentally. Using an in vivo rat model, we determined the effects of perinatal VD deficiency on overall pulmonary function and the tracheal contraction as a functional marker of airway contractility. One month before pregnancy, rat dams were put on either a no cholecalciferol-added or a 250, 500, or 1,000 IU/kg cholecalciferol-added diet, which was continued throughout pregnancy and lactation. At postnatal day 21, offspring plasma 25(OH)D levels and pulmonary function (whole body plethysmography and tracheal contraction response to acetylcholine) were determined. 25(OH)D levels were lowest in the no cholecalciferol-supplemented group, increasing incrementally in response to cholecalciferol supplementation. Compared with the 250 and 500 IU/kg VD-supplemented groups, the no cholecalciferol-supplemented group demonstrated a significant increase in airway resistance following methacholine challenge. However, the cholecalciferol deficiency-mediated increase in tracheal contractility in the cholecalciferol-depleted group was only blocked by supplementation with 500 IU/kg cholecalciferol. Therefore, in addition to altering alveolar epithelial-mesenchymal signaling, perinatal VD deficiency also alters airway contractility, providing novel insights to asthma pathogenesis in perinatally VD-deficient offspring. Perinatal VD supplementation at 500 IU/kg appears to effectively block these effects of perinatal VD deficiency in the rat model used, providing a strong clinical rationale for effective perinatal VD supplementation for preventing childhood asthma.