Hakan Mollaoglu

The protective effect of fish n-3 fatty acids on cerebral ischemia in rat hippocampus

Reactive oxygen species (ROS) have been implicated in the pathogenesis of cerebral injury after ischemia-reperfusion (I/R). Fish n-3 essential fatty acids (EFA), contain eicosapentaenoic acids (EPA) and docosahexoenoic acids (DHA), exhibit antioxidant properties. DHA is an important component of brain membrane phospholipids and is necessary for the continuity of neuronal functions. EPA prevents platelet aggregation and inhibits the conversion of arachidonic acid into thromboxane A(2) and prostaglandins. They have been suggested to be protective agents against neurological and neuropsychiatric disorders. In this study, the neuroprotective effects of fish n-3 EFA on oxidant-antioxidant systems and number of apoptotic neurons of the hippocampal formation (HF) subjected to cerebral I/R injury was investigated in Sprague-Dawley rats. Six rats were used as control (Group I). Cerebral ischemia was produced by occlusion of both the common carotid arteries combined with hypotension for 45 min, followed by reperfusion for 30 min, in rats either on a standard diet (Group II) or a standard diet plus fish n-3 EFA (Marincap((R)), 0.4 g/kg/day, by gavage) for 14 days (Group III). At the end of procedures, the rats were sacrificed and their brains were removed immediately. The levels of malonedialdehyde (MDA) and nitric oxide (NO) and activities of superoxide dismutase (SOD) and catalase (CAT) were measured in left HF. In addition, the number of apoptotic neurons was counted by terminal transferase dUTP nick end labelling (TUNEL) assay in histological samples of the right HF. We found that SOD activities and MDA levels increased in Group III rats compared with Group II rats. On the other hand, CAT activities and NO levels were found to be decreased in Group III rats compared with Group II rats. Additionally, the number of apoptotic neurons was lower in Group III in comparison with Group II rats. The present findings suggest that fish n-3 EFA could decrease the oxidative status and apoptotic changes in ischemic rat hippocampal formation. Dietary supplementation of n-3 EFA may be beneficial to preserve or ameliorate ischemic cerebral vascular disease.

The influence of dexmedetomidine on ischemic rat hippocampus

In our study, we evaluated the neuroprotective effects of dexmedetomidine on oxidant-antioxidant systems, pro-inflammatory cytokine TNF-alpha and number of apoptotic neurons on hippocampus and dentate gyrus after transient global cerebral I/R injury. Eighteen rats divided into 3 groups, equally. Group I rats were used as shams. For group II and III rats, they were prepared for transient global cerebral ischemia using a four-vessel-occlusion model. 5 mL/kg/h 0.9% sodium chloride was infused to the Group II and 3 microg/kg/h/5 ml dexmedetomidine was infused to the Group III for 2 h after I/R injury. The levels of MDA and NO and activities of SOD and CAT were measured in the left hippocampus tissue. The levels of TNF-alpha concentration were measured in the plasma. The number of apoptotic neurons was counted by TUNNEL method in histological samples of right hippocampus tissue. MDA and NO levels increased in Group II compared with Group I rats (p=0.002, p=0.002, respectively). In group III, MDA and NO levels decreased as compared to Group II (p=0.015, p=0.002, respectively). SOD and CAT activities increased in Group III as compared to Group II rats (p=0.002, p=0.002, respectively). The decrease in TNF-alpha levels of group III was significant as compared to group II (p=0.016). The number of apoptotic neurons in group III was lower than Group II rats. Our study showed that dexmedetomidine has a neuroprotective effect on hippocampus and dentate gyrus of rats after transient global cerebral I/R injury.

Chronic prenatal exposure to the 900 megahertz electromagnetic field induces pyramidal cell loss in the hippocampus of newborn rats

Widespread use of mobile phones which are a major source of electromagnetic fields might affect living organisms. However, there has been no investigation concerning prenatal exposure to electromagnetic fields or their roles in the development of the pyramidal cells of the cornu ammonis in postnatal life. Two groups of pregnant rats, a control group and an experimental group, that were exposed to an electromagnetic field were used. For obtaining electromagnetic field offspring, the pregnant rats were exposed to 900 megahertz electromagnetic fields during the 1–19th gestation days. There were no actions performed on the control group during the same period. The offspring rats were spontaneously delivered—control group (n = 6) and electromagnetic field group (n = 6). Offspring were sacrificed for stereological analyses at the end of the 4th week. Pyramidal cell number in rat cornu ammonis was estimated using the optical fractionator technique. It was found that 900 megahertz of electromagnetic field significantly reduced the total pyramidal cell number in the cornu ammonis of the electromagnetic field group (P < 0.001). Therefore, although its exact mechanism is not clear, it is suggested that pyramidal cell loss in the cornu ammonis could be due to the 900 megahertz electromagnetic field exposure in the prenatal period.

Melatonin modulates 900 MHz microwave-induced lipid peroxidation changes in rat brain:

Microwaves (MW) from cellular phones may affect biological systems by increasing free radicals, which may enhance lipid peroxidation levels of the brain, thus leading to oxidative damage. Melatonin is synthesized in and secreted by the pineal gland at night and exhibits anti-oxidant properties. Several studies suggest that supplementation with anti-oxidant can influence MW-induced brain damage. The present study was designed to determine the effects of MW on the brain lipid peroxidation system, and the possible protective effects of melatonin on brain degeneration induced by MW. Twenty-eight Sprague-Dawley male rats were randomly divided into three groups as follows: (1) sham-operated control group (N-8); (2) study 900-MHz MW-exposed group (N-8); and (3) 900-MHz MW-exposed-melatonin (100 mg/kg sc before daily MW exposure treated group) (N-10). Cortex brain and hippocampus tissues were removed to study the levels of lipid peroxidation as malonyl dialdehyde. The levels of lipid peroxidation in the brain cortex and hippocampus increased in the MW group compared with the control group, although the levels in the hippocampus were decreased by MW-melatonin administration. The brain cortex lipid peroxidation levels were unaffected by melatonin treatment. We conclude that melatonin may prevent MW-induced oxidative changes in the hippocampus by strengthening the anti-oxidant defense system, by reducing oxidative stress products.

Prevention of mobile phone induced skin tissue changes by melatonin in rat: an experimental study:

Most of the mobile phones in Turkey emit 900 MHz radiation which is mainly absorbed by the skin and, to a lesser extent, muscle. The aim of this study was to investigate the effects the 900 MHz electromagnetic irradiation emitted by these devices on the induction of histopathologic changes in skin and the effect of melatonin (Mel) on any of these changes. Thirty male Wistar-Albino rats were used in the study. The experimental groups were composed of: a nontreated control group, an irradiated group (IR) without Mel and an irradiated with Mel treatment group (IR + Mel). 900 MHz radiation was applied to IR group for 10 days (30 min/day). The IR + Mel group received 10 mg/kg per day melatonin in tap water for 10 days before irradiation. At the end of the tenth day, the skin graft was excized from the thoraco-abdominal area. Histopathologic changes in skin were analyzed. In the IR group, increased thickness of stratum corneum, atrophy of epidermis, papillamatosis, basal cell proliferation, increased granular cell layer (hypergranulosis) in epidermis and capillary proliferation, impairment in collagen tissue distribution and separation of collagen bundles in dermis were all observed compared to the control group. Most of these changes, except hypergranulosis, were prevented with melatonin treatment. In conclusion, exposure to 900 MHz radiation emitted by mobile phones caused mild skin changes. Furthermore, melatonin treatment can reduce these changes and may have a beneficial effect to prevent 900 MHz mobile phone-induced rat skin changes.

The protective effect of fish n-3 fatty acids on cerebral ischemia in rat prefrontal cortex

This study presents neuroprotective effects of fish n-3 EFA on the prefrontal cortex after cerebral ischemia and reperfusion. Eighteen rats divided into three groups. Group A rats were used as control. Cerebral ischemia and reperfusion was produced in rats either on a standard diet (Group B) or a standard diet plus fish n-3 EFA for 14 days (Group C). The malondialdehyde (MDA) levels and activities of superoxide dismutase (SOD) and catalase (CAT) were measured and the number of apoptotic neurons was counted. The levels of MDA and activities of SOD increased in Group B rats as compared to Group A rats, and decreased in Group C rats as compared to Group B rats. The activities of CAT increased in Group C as compared to Group B rats. The number of apoptotic neurons in the prefrontal cortex was lower in Group C as compared to Group B rats.

No effects of 900 MHz and 1800 MHz electromagnetic field emitted from cellular phone on nocturnal serum melatonin levels in rats

In this study, the effects of exposure to a 900 MHz and 1800 MHz electromagnetic field (EMF) on serum nocturnal melatonin levels of adult male Sprague-Dawley rats were studied. Thirty rats were used in three independent groups, 10 of which were exposed to 900 MHz, 10 of which were exposed to 1800 MHz and 10 of which were sham-exposed (control). The exposures were performed 30 min/day, for five days/week for four weeks to 900 MHz or 1800 MHz EMF. Control animals were kept under the same environmental conditions as the study groups except with no EMF exposure. The concentration of nocturnal melatonin in the rat serum was measured by using a radioimmunoassay method. There were no statistically significant differences in serum melatonin concentrations between the 900 MHz EMF group and the sham-exposed group (P-0.05). The values at 12:00 pm were 39.119 / 6.5 pg/mL in the sham-exposed group and 34.979 / 5.1 pg/mL in the 900 MHz EMF-exposed group. Also, there were no statistically significant differences in serum melatonin concentrations between the sham-exposed group and the 1800 MHz EMF-exposed group (P-0.05). The values at 12:00 pm were 39.119 / 6.5 pg/mL in the sham-exposed group and 37.969 / 7.4 pg/mL in the exposed group. These results indicate that mobile phones, emitting 900 and 1800 MHz EMF, have no effect on nocturnal serum melatonin levels in rats.

Novel approach for the prevention of contrast nephropathy

OBJECTIVE To date, there is no effective treatment of contrast medium (CM)-induced nephropathy. Multiple studies documented a protective role of hydration and N-acetylcystein (NAC) as prophylactic agents against CM-induced nephropathy in a high-risk population. In the present study, we investigated a new antioxidant agent, caffeic acid phenethyl ester (CAPE), and compare with NAC against contrast nephropathy. METHODS Forty-two adult male rats were divided into six experimental groups, which were control, injected with intravenous (i.v.) CM, injected with i.p. CAPE, injected with i.p. NAC, injected with i.v. CM pretreated with i.p. CAPE, injected with i.v. CM pretreated with i.p. NAC. CAPE and NAC were given daily throughout the study. All rats were deprived of water for 24h at the third day of the study and then contrast medium was administered to CM, CAPECM and NACCM groups. The rats were sacrificed at the fifth day. Oxidant-antioxidant status was determined in renal tissues. The severity of injury was scored with a light microscope in renal tissue. Plasma creatinine levels were measured. RESULTS Renal injury scores were higher in CAPECM and NACCM groups than in control, CAPE and NAC groups, but lower than the CM group. Likewise, creatinine levels of CAPECM and NACCM groups were higher than the control groups but they were significantly lower than the level of the CM group. Creatinine levels of the NACCM group were significantly higher than the CAPECM group. Malondialdehyde levels were significantly lower in CAPECM and NACCM groups than the CM group. CONCLUSION CAPE might protect renal structure and functions as well as NAC against CM injury.

Erythrocyte Oxidant/Antioxidant Status in Essential Hyperhidrosis

Essential Hyperhidrosis is a disorder of excessive, bilateral, and relatively symmetric sweating occurring in the axillae, palms, soles, or craniofacial region without obvious etiology. Nitric oxide may play a physiological part in the production and/or excretion of sweat in skin eccrine glands. Tempol, a SOD mimetic, increases the half-life of NO and results in vasodilatation, hypotension, and reflex activation of sympathetic nervous system. Reactive oxygen species (ROS) may directly activate both central and peripheral sympathetic nervous system activity. We assessed the levels of malondialdehyde (MDA), the activities of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) of red blood cells in patients with essential hyperhidrosis (n = 31) compared to age-and sex-matched healthy controls (n = 28). Erythrocyte activities of SOD and level of MDA were detected significantly higher (p = 0.020, p = 0.004 and respectively) and activities of CAT and GSH-Px were significantly lower (p = 0.0001, p = 0.0001 respectively) in patients than controls. Our results support the hypothesis that oxidative damage resulting from increased ROS production along with insufficient capacity of antioxidant mechanisms may be involved in pathogenesis of EH.

Association analyses of depression, anxiety, and physical fitness parameters in Turkish obese adults.

OBJECTIVE This study aims to investigate the associations among depression, anxiety, aerobic exercise capacity, body fat percentage, sum of skinfolds, abdomen circumference, and waist to hip ratio on the basis of body mass index (BMI) in adults. METHODS The subjects of the study were 60 obese participants (30 women, 30 men) with BMIs over 30 kg/m{2}and 60 healthy controls (30 women, 30 men) with BMIs of 18-25 kg/m{2}. Body fat percentage was calculated from the skinfold thicknesses using the formula. Body circumference measurements were performed using a tape measure. Maximal aerobic capacity (VO(2)max) was determined by Astrand submaximal exercise protocol. Two self-reported questionnaires, Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI), were administered to all participants. RESULTS BMI, body fat percentage, sum of skinfolds, abdomen circumference, and waist to hip ratio were found to be higher in obese groups as compared to the controls, while VO(2)max (ml/kg/min) values were lower in both genders. In males, BAI scores and mild-level anxiety percentage values were higher in the obese group than in the control group. There was no significant difference for BDI scores and levels between the obese and control groups in both genders. There was also no significant difference in BAI scores and levels between the obese and control groups in women. CONCLUSION The fact that physical fitness being found poor in obese shows the existence of a condition that might constitute an increased tendency for obesity-related disorders. In addition, it was suggested that, in Turkey, attitudes toward obesity change depending on gender.