Hakkı Gökbel

The association of nocturnal serum melatonin levels with major depression in patients with acute multiple sclerosis

The association of nocturnal serum melatonin levels was investigated in acute multiple sclerosis (MS) patients with major depression (MD). The sample comprised 13 patients with MD and 12 with no psychiatric disorders admitted to our clinic due to acute MS attacks. Psychiatric evaluation was performed with the Structured Clinical Interview for DSM-IV (SCD-I). The level of depressive symptoms was assessed with the Beck Depression Scale (BDS). Blood samples were taken from the patients to determine melatonin level at 03.30 h and 10.00 h before steroid treatment started. Melatonin levels were determined using the ELISA test. Nocturnal serum melatonin levels (21.2+/-17.1 pg/ml) of the patients with MD were significantly lower than those (51.5+/-18.3 pg/ml) of the patients without MD. A significant negative correlation was found between BDS scores and nocturnal serum melatonin levels. These findings suggest that a melatonin deficiency may be among the factors involved in the occurrence of depression in MS patients.

Physical disability, psychological status, and health-related quality of life in older hemodialysis patients and age-matched controls

We aimed at comparing the elderly adults and normal subjects with regard to their disability, psychological status, and quality of life (QOL). One hundred and twenty‐five dialysis patients and 61 controls were recruited in the study. Depression and anxiety symptoms of the patients were evaluated with the Psychological Symptom Screening List (SCL 90‐R). For evaluating the disability, the Rivermead mobility index (RMI) was utilized. For evaluating the QOL, we used the short form‐36 (SF‐36) scale. The Rivermead mobility index of the patients (9.6±3.4) was found. When compared with controls, dialysis patients had higher levels of disability (p=0.0001). Depression and anxiety symptom scores of these patients were also significantly higher than that of the controls (p<0.05). There was a correlation between the disability and depression symptom scores (r: 0.171, p=0.037). Both physical and mental capacity scores of the dialysis patients were lower than those of the controls (p<0.05 and p<0.05) QOL scores for elderly hemodialysis patients were found to be lower. Their disability was higher, making them dependable on others during their daily lives. Specific exercise programs should be developed for these patients. Even the smallest effort in this regard will result in improvements in physical functioning while bringing them significant benefits.

The Effect of Grape Seed Extracts on Serum Paraoxonase Activities in Streptozotocin-Induced Diabetic Rats

Procyanidins, a group of flavonoids, are oligomeric forms of catechins that are abundant in red wine, grapes, cocoa, and apples. Paraoxonase acts as an antioxidant enzyme and protects low-density lipoprotein-cholesterol against oxidation. In our study we aimed to evaluate the effects of grape seed extract (GSE) on paraoxonase activities in streptozotocin-induced diabetic rats. Our study included four groups of rats: Group I (n = 8), control; Group II (n = 10), GSE-supplemented; Group III (n = 6), streptozotocin-induced diabetic; and Group IV (n = 7), GSE-supplemented diabetic rats. Serum paraoxonase activities were determined with a spectrophotometric method. Paraoxonase activities in Group III were significantly lower than in the other three groups (P < .001, P < .001, and P = .005 for Groups I, II, and IV, respectively), and Group IV showed increased paraoxonase activities compared to Group III (P = .005). This is the first study to show an association between paraoxonase status and GSE supplementation and demonstrated that GSE increased paraoxonase activities. This beneficial effect of GSE was more obvious in the diabetic group, which was more prone to atherosclerotic events compared to the healthy population.

Serum leptin, adiponectin, resistin and ghrelin levels in psoriatic patients treated with cyclosporin

Cyclosporin has various effects on adipose tissue and glucose metabolism. This situation may lead to changes in serum levels of adipocyte‐derived cytokines which have influence on the pathogenesis of psoriasis. The aim of this study was to evaluate the effect of cyclosporin treatment on some adipocyte‐derived cytokines in psoriatic patients. This case–control study was performed between June 2009 and March 2010, at the Department of Dermatology of Meram School of Medicine. Serum leptin, adiponectin, resistin and ghrelin levels were assessed in 26 patients with psoriasis before and after cyclosporin treatment and body mass index‐matched 26 healthy control subjects. The adipokines levels were compared between the groups. Serum leptin, ghrelin, resistin and adiponectin levels in patients with psoriasis before the treatment were higher than those of the control group but the differences were not statistically significant. A positive correlation between serum leptin and family history of psoriasis was detected (r = 0.398, P = 0.044). A strong negative correlation between the Psoriasis Area and Severity Index and serum ghrelin levels was seen (r = −0.52, P = 0.001) and there was a strong positive correlation between the Nail Psoriasis Severity Index and serum resistin levels (r = 0.62, P = 0.001). Following the treatment, a significant increase was seen in the serum level of adiponectin (P = 0.02) and resistin (P = 0.003). The correlations between the adipokines and the disease parameters before the treatment were lost after the treatment. Our results suggest that levels of some adipocyte‐derived cytokines in psoriatic patients are affected by cyclosporin treatment.

Effects of grape seed extract supplementation on exercise-induced oxidative stress in rats.

The aim of the present study was to investigate the effects of grape seed extract (GSE) supplementation on exercise performance and oxidative stress in acutely and chronically exercised rats. A total of sixty-four male rats were used in the study. Rats were divided into six groups: control, chronic exercise control, acute exercise control (AEC), GSE-supplemented control, GSE-supplemented chronic exercise and GSE-supplemented acute exercise groups. Chronic exercise consisted of treadmill running at 25 m/min, 45 min/d, 5 d a week for 6 weeks. Rats in the acute exercise groups were run on the treadmill at 30 m/min until exhaustion. GSE were given at 100 mg/kg of body weight with drinking water for 6 weeks. Plasma was separated from blood samples for the analysis of oxidative stress markers. There was no significant difference in time of exhaustion between the acute exercise groups. Plasma malondialdehyde (MDA) levels were higher in the acute exercise groups and lower in the chronic exercise groups. GSE supplementation decreased MDA levels. Xanthine oxidase and adenosine deaminase activities were higher in the AEC group compared to all the other groups. NO levels were increased with both chronic exercise and GSE supplementation. Superoxide dismutase and glutathione peroxidase activities were lower in the acute exercised groups and higher in the chronic exercised groups. GSE supplementation caused an increase in antioxidant enzyme activities. In conclusion, GSE supplementation prevents exercise-induced oxidative stress by preventing lipid peroxidation and increasing antioxidant enzyme activities.

The Effect of Supplementation of Grape Seed Proanthocyanidin Extract on Vascular Dysfunction in Experimental Diabetes

Increased oxidative stress and impaired endothelium-dependent relaxation could underlie many of the vascular complications associated with diabetes. We aimed to investigate the effect of supplementation with grape seed proanthocyanidin extract (GSPE), a natural antioxidant, on vascular responses and oxidative stress in streptozotocin-induced diabetic rats. Male Sprague-Dawley rats were divided into three groups: control rats, untreated diabetic rats, and GSPE (100 mg/kg, for 6 weeks)-supplemented diabetic rats. Thoracic aorta rings of the rats were mounted in organ baths, and relaxant responses to acetylcholine (ACh), A23187, and sodium nitroprusside (SNP) were assayed in tissues precontracted with 60 mM KCl. Plasma samples used for the measurement of malondialdehyde (MDA) level and superoxide dismutase (SOD) activity. The endothelium-dependent relaxations in response to ACh and A23187 were impaired, but endothelium-independent relaxation in response to SNP did not change in diabetic rats. Supplementation with GSPE significantly improved the relaxant responses to ACh and A23187. The MDA level was significantly elevated and the plasma SOD activity was decreased in diabetic rats, but supplementation with GSPE attenuated the elevated MDA levels and increased plasma SOD activity. Thus supplementation of GSPE may attenuate oxidative stress through the inhibition of lipid peroxidation and may restore endothelial function and reduce the risk of vascular disease in diabetes.

Effects of Coenzyme Q10 Supplementation on Plasma Adiponectin, Interleukin-6, and Tumor Necrosis Factor-α Levels in Men

The aim of the study was to determine the effects of coenzyme Q10 supplementation on plasma adiponectin, interleukin (IL)-6, and tumor necrosis factor (TNF )-alpha levels in sedentary men. Fourteen healthy, nonsmoking, sedentary men participated in the study. The protocol was approved by the Ethical Committee of our institution. This study was a randomized, double-blind, crossover trial. Blood samples were collected from all participants before coenzyme Q10 or placebo supplementation. The participants were randomly allocated to two groups. Seven participants received oral coenzyme Q10 (100 mg/day) supplementation, and seven participants received placebo (glucose) for 8 weeks. At the end of the 8 weeks, a second blood sampling was performed. After a 4-week washout period, placebo was given to the participants who used coenzyme Q10 the first time, and vice versa, and blood sampling was repeated. Plasma was stored at -80 degrees C until the time of analysis for adiponectin, IL-6, and TNF-alpha. Both CoQ10 and placebo supplementation did not affect plasma adiponectin and TNF-alpha levels. IL-6 level increased with coenzyme Q10 supplementation, but this increase did not differ from that seen with placebo supplementation. Coenzyme Q10 supplementation did not affect plasma adiponectin, IL-6, and TNF-alpha levels in sedentary men.

Effects of grape seed polyphenols on oxidative damage in liver tissue of acutely and chronically exercised rats.

The objective of the present study was to investigate the effects of grape seed extract (GSE) supplementation on oxidative stress and antioxidant defense markers in liver tissue of acutely and chronically exercised rats. Rats were randomly assigned to six groups: Control (C), Control Chronic Exercise (CE), Control Acute Exercise (AE), GSE‐supplemented Control (GC), GSE‐supplemented Chronic Exercise(GCE) and GSE‐supplemented Acute Exercise (GAE). Rats in the chronic exercise groups were subjected to a six‐week treadmill running and in the acute exercise groups performed an exhaustive running. Rats in the GSE supplemented groups received GSE (100 mg.kg−1.day−1) in drinking water for 6 weeks. Liver tissues of the rats were taken for the analysis of malondialdehyde (MDA), nitric oxide (NO) levels and total antioxidant activity (AOA) and xanthine oxidase (XO) activities. MDA levels decreased with GSE supplementation in control groups but increased in acute and chronic exercise groups compared to their non‐supplemented control. NO levels increased with GSE supplementation. XO activities were higher in AE group compared to the CE group. AOA decreased with GSE supplementation. In conclusion, while acute exercise triggers oxidative stress, chronic exercise has protective role against oxidative stress. GSE has a limited antioxidant effect on exercise‐induced oxidative stress in liver tissue. Copyright

Age and sex affect spatial and emotional behaviors in rats: the role of repeated elevated plus maze test.

The main objective of the study was to investigate the effects of age and sex differences on locomotor activity, learning and memory in rats. Another objective was to investigate whether repeated elevated plus maze tests induce anxiety in rats. Eighty Wistar rats were divided into eight groups according to their sex, age and anxiety status. Locomotor activity was assessed in open field. Repeated anxiety tests were performed in elevated plus maze. Spatial learning and memory were evaluated with the Morris water maze. All behavioral tests were recorded online and analyzed offline with an analytical software. Exploratory behavior was lower in anxiety-induced rats. Male rats had lower anxiety levels, locomotor activity and exploratory behavior compared to females. During the training period of Morris water maze latency to find platform, total distance traveled and average swimming speed decreased in all groups with repeated tests and young rats generally were faster than aged rats. During the probe trial, although the number of platform crossings was not affected, time spent in the platform zone was higher in the young groups compared to the aged groups. In conclusion, age and sex affect locomotor activity, learning and memory in different aspects.

Protective effects of curcumin supplementation on intestinal ischemia reperfusion injury.

The aim of this study was to investigate the effects curcumin on inflammation and oxidative stress markers in the intestinal ischemia reperfusion (IIR) injury induced rats. Rats were divided into four groups: sham (S), intestinal IR (IIR), curcumin plus sham (CS), and curcumin plus intestinal IR (CIIR). Curcumin was given 200 mg kg⁻¹ for 20 days. IIR was produced by 45 min of intestinal ischemia followed by a 120 min of reperfusion. Although interleukin-6 levels tended to increase in IIR group tumor necrosis factor-α levels were not different. Intestinal myeloperoxidase activity in CS group was lower than IIR group. In intestine and heart tissues, malondialdehyde levels in CS and CIIR groups were lower than S and IIR groups. Superoxide dismutase activity in CIIR group was higher than IIR group in intestine and lung tissues. Curcumin has a protective role against ischemia reperfusion injury.