The effects of bee venom on behavior and the role of leptin in rats.

The aim of this study is to evaluate the dose­dependent effect of bee venom (BV) on behavioral functions in rats and the physiological role of leptin in the prefrontal cortex, hippocampus, and amygdala tissues. Adult Sprague­Dawley male rats were used in the experiments. The rats were divided into three groups of control, 0.1 mg/kg BV, and 0.5 mg/kg BV. The rats were injected with BV subcutaneously for 15 consecutive days. The open field test (OFT), the elevated plus maze test (EPM), and the forced swimming test (FST) were performed as behavioral assessments. Animals were sacrificed, and brain regions were removed. Leptin levels were measured in various brain regions by ELISA. In the OFT, the total distance and speed for the 0.1 mg/kg BV group increased compared to controls and the 0.5 mg/kg BV group. In the EPM, the 0.1 mg/kg BV group remained in the open arm for a significantly longer period of time compared to the other groups. In the FST, the 0.5 mg/kg BV group was more mobile than the other groups. Leptin levels in the prefrontal cortex were significantly higher in the 0.1 mg/kg BV group compared to the control and 0.5 mg/kg groups. There were no significant differences between groups in hippocampus and amygdala leptin levels. The results of the study show that BV has a positive effect on behavioral parameters. BV may have a positive effect on anxiety­ and depression­like behaviors by increasing leptin levels in the prefrontal cortex.

The effects of Spirulina platensis on behavior in adolescent rats fed a high-fat diet.

In recent years, childhood overweight and obesity have become a universal public health problem. Obesity may lead to cognitive disorders, depression and anxiety by affecting neuronal processes. Spirulina platensis (SP), a species of microalgae from the Chlorophyceae green algae class, has neuroprotective effects and may reduce body weight. In this study, we aimed to investigate the effects of SP on behavior alongside the role of leptin and Sirtuin-1 in fed with high-fat diet (HFD) adolescent rats. Four-week-old Sprague Dawley male rats were divided into four groups: control, HFD, HFD + SP150 (150 mg/kg/day SP, orally), HFD + SP450 (450 mg/kg/day SP, orally). Rats except for the control group exposed to 60% HFD along 12 weeks. Last 6 weeks SP or vehicle administered. After the behavioral tests, leptin and Sirtuin-1 levels in prefrontal cortex and hippocampus regions were evaluated. SP150 significantly reduced body weight compared with HFD group. The time spent in the center of open field increased significantly in SP150-treated rats compared with HFD. SP150 and SP450 significantly decreased immobility time in forced swim test compared with HFD. Leptin levels in HFD group were significantly lower in prefrontal cortex compared to control group. Leptin levels of the HFD + SP450 group were significantly higher than HFD group in the hippocampus. There was no significant difference between groups in Sirtuin-1 levels. In conclusion, SP supplementation in adolescence period might positively affect chronic high fat-induced anxiety-like and depressive-like behavior by partially affecting brain leptin levels and without affecting Sirtuin-1 levels.

Gender differences in effects of prenatal and postnatal exposure to electromagnetic field and prenatal zinc on behaviour and synaptic proteins in rats.

Humans are exposed to electromagnetic fields (EMF) from various sources throughout life. Because humans are easily impacted by environmental factors during early development, it is believed that EMF can cause structural and functional changes on the developing brain that may lead to behavioural changes. This paper investigates the impact of EMF exposure and zinc supplementation during the prenatal and postnatal periods on behavioural changes and synaptic proteins in a gender-dependent manner. Pups from four groups of pregnant rats were used: Sham, EMF (5 days/wk, 4 h/day EMF-exposure applied), Sham+Zinc (5 days/wk, 5 mg/kg/day zinc applied) and EMF+Zinc (5 days/wk, 4 h/day EMF-exposure and 5 mg/kg/day zinc applied). EMF exposure and zinc supplementation were initiated from the first day of pregnancy to the 42nd postnatal day. Zinc levels in blood, NLGN3 and SHANK3 levels in hippocampus and amygdala, and synaptic structures in amygdala were examined. Behavioural tests showed that EMF exposure had no effect on social behaviour, but adversely affected activity and exploratory behaviour, and led to increased anxiety formation. Zinc supplementation had a partially positive effect on female, but not male offspring. SHANK3 and NLGN3 proteins were significantly lower in EMF groups, however, no positive effect of zinc supplementation was found. In conclusion, EMF exposure may alter the levels of synaptic proteins in the developing brain, leading to behavioural changes in a gender-dependent manner. Evaluation of zinc supplementation at different doses could be beneficial to prevent or reduce the behavioural and structural effects of EMF.

The effects of bee venom on liver and skeletal muscle in exhaustive swimming rats.

Oxidative damage and proinflammatory cytokines are involved in exhaustive exercise-induced fatigue. This study aimed to investigate the effects of bee venom, a natural toxin, on fatigue and tissue damage in rats that underwent forced swimming exercise. Rats were divided into four groups: control, swimming exercise (SE), bee venom (BV) and swimming exercise + bee venom (SE + BV). SE and SE + BV groups were subjected to forced swimming (load of 7% body weight) for 5 days. BV and SE + BV groups were injected with 1 mg/kg BV subcutaneously. Swimming time, blood lactate and TNF-α levels, MDA and GSH levels in liver and gastrocnemius muscle were evaluated. Swimming time was shorter in SE + BV group than SE group. There was no difference in lactate levels between SE and SE + BV groups. MDA and GSH levels were increased in SE, BV and SE + BV groups. TNF-α levels were increased in BV group compared to control and SE groups. Our study demonstrated that BV administration before exhaustive exercise in rats did not provide anti-fatigue effect. Additionally, BV did not show anti-inflammatory activity and had different effects on antioxidant capacity at tissue level. Further research might explore the effects of different doses and durations of BV on exhaustive exercise.

Effect of decorin protein administration on rat sciatic nerve injury: an experimental study.

INTRODUCTION: Peripheral nerve traumas are common injuries in young adult population. The myriad of techniques and medications have been defined to obtain better recovery but none of them was proved to have superior effect. This study aims to determine the anti-fibrotic effect of the decorin on sciatic nerve injury in order to enhance functional outcome. MATERIALS AND METHODS: 24 12-week-old male Sprague-Dawley rats (350-400 gr) were divided into four groups. The sciatic nerve was dissected and exposed; a full-thickness laceration was created 1.5 cm proximal to the bifurcation point and 1.5 cm distal to where it originated from the lumbosacral plexus. Motor and sensory tests were conducted before and after the operations for evaluating the nerve healing. RESULTS: There was a statistically significant difference between DCN bolus and PBS bolus group. (p<0.0001, p<0.05) in neuromotor tests. Increase of the latency was significantly lower in DCN bolus and infusion group when compared with the PBS bolus group. (p<0,001). All operated gastrocnemius muscles were atrophic compared with the contralateral side. The differences between the averages in the sciatic functional index, the improvement of the DCN infusion group was 8.6 units better than the PBS group and 4.4 units better than the DCN bolus group. When the amount of stimulation was 10 mV at the proximal segment in electromyography, there was no significant difference between the DCN bolus and sham groups. (p> 0.05, p = 0.6623). CONCLUSION: Decorin protein reduces the fibrosis and enhances the motor and sensory recovery both clinically and histologically. Despite the high cost, short half-life and production issues, this protein could be administered after the microsurgical repair but more studies are required to overcome the limitations.

The Effects of Prenatal and Postnatal Exposure to 50-Hz and 3 mT Electromagnetic Field on Rat Testicular Development.

Background and objectives: It has been shown that electromagnetic fields (EMFs) have negative effects on the reproductive system. The biological effects of EMF on the male reproductive system are controversial and vary depending on the frequency and exposure time. Although a limited number of studies have focused on the structural and functional effects of EMF, the effects of prenatal and postnatal EMF exposure on testes are not clear. We aimed to investigate the effects of 50-Hz, 3-mT EMF exposure (5 days/wk, 4 h/day) during pre- and postnatal periods on testis development. Materials and Methods: Pups from three groups of Sprague-Dawley pregnant rats were used: Sham, EMF-28 (EMF-exposure applied during pregnancy and until postnatal day 28), EMF-42 (EMF-exposure applied during pregnancy and until postnatal day 42). The testis tissues and blood samples of male offspring were collected on the postnatal day 42. Results: Morphometric analyses showed a decrease in seminiferous tubule diameter as a result of testicular degeneration in the EMF-42 group. Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels were decreased in the EMF-42 group. Lipid peroxidation levels were increased in both EMF groups, while antioxidant levels were decreased only in the EMF-28 group. We found decreased levels of vascular endothelial growth factor (VEGF) and insulin-like growth factor-1 (IGF1) in the EMF-42 group, and decreased levels of the SRC homology 3 (SH3) and multiple ankyrin repeat domain (SHANK3) in the EMF-28 group in the testis tissue. Conclusions: EMF exposure during pre- and postnatal periods may cause deterioration in the structure and function of testis and decrease in growing factors that would affect testicular functions in male rat pups. In addition to the oxidative stress observed in testis, decreased SHANK3, VEGF, and IGF1 protein levels suggests that these proteins may be mediators in testis affected by EMF exposure. This study shows that EMF exposure during embryonic development and adolescence can cause apoptosis and structural changes in the testis.

Direct kidney injury or lower extremity ischemia induced indirect kidney injury: Which one is more harmful for kidneys?

OBJECTIVES: The aim of this study was to investigate and compare the severity of kidney damage following lower limb ischemia-reperfusion and direct kidney ischemia-reperfusion. METHODS: Thirty Sprague Dawley male rats were randomly divided into three groups; lower extremity ischemia-reperfusion group (Group 2), renal ischemia-reperfusion group (Group 3) and control (anesthesia and median laparotomy only) (Group 1). In group 3, 1-h ischemia was performed on the kidney and in group 2, 1-h ischemia was performed on the left lower extremity. This procedure was followed by reperfusion for 24 h. Renal tissues were removed after the reperfusion period and the groups were evaluated for glutathioneperoxidase activity, malondialdehyde and GSH levels, and furthermore, their histolopathological scores were calculated. RESULTS: Renal malondialdehyde levels were significantly higher in Group 2 and Group 3 than they were in the Control group. There was no significant difference in renal malondialdehyde levels between Group 2 and Group 3. Kidney glutathione (GSH) levels were statistically lower in Group 2 and Group 3 than in the Control group. No statistically significant difference was found between Group 2 and Group 3 regarding their GSH levels. In histological evaluation, there was no statistically significant difference between Group 2 and Group 3 in terms of kidney damage score. CONCLUSIONS: This study has identified that lower extremity ischemia induces remote kidney damage with similar features to kidney injury, occurring after direct kidney ischemia-reperfusion.

Protective effect of alpha lipoic acid on 4-vinylcyclohexene diepoxide induced primary ovarian failure in female rats.

OBJECTIVE: The effects of alpha lipoic acid (ALA) and its possible mechanisms in treating Primary ovarian failure (POF) model was studied with 4 vinylcyclohexene diepoxide (VCD). MATERIAL AND METHODS: Rats were divided into 4 groups (n = 7) as Control, VCD, VCD + ALA and ALA. POF model was induced by applying VCD intraperitoneally and ALA was administered by oral gavage as 100 mg/day to the VCD + ALA and ALA groups. RESULTS: At the end of 42 days, ovarian and uterine tissues were received. The number of primordial and primary follicles were increased and corpus luteum and cystic follicles were decreased in ovarian tissues in VCD + ALA group compared to VCD group. Caspase-3 immunoreactivity in follicular cells was decreased in VCD + ALA group compared to VCD group. eNOS immunoreactivity and eNOS levels were decreased in VCD group and increased in VCD + ALA group while iNOS immunoreactivity and iNOS levels were increased in VCD group, decreased in VCD + ALA group in ovary and uterine tissue. Plasma FSH and LH hormone levels were increased in the VCD but decreased in VCD + ALA group. Estradiol level decreased in the VCD group compared to the other groups. The MDA values were significantly increased in the VCD + ALA group compared to VCD group. In addition, the levels of GSH values were decreased in VCD + ALA group compared to VCD group. CONCLUSION: Alpha lipoic acid treatment of rats with VCD-induced POF had a beneficial effect on reducing ovarian damage by improving histological, immunohistochemical, hormone level and oxidative stress markers. Our results show that ALA is an effective treatment of VCD-induced POF rats.

How important is the damage to the liver after lower limb ischemia-reperfusion? An experimental study in a rat model.

BACKGROUND: The aim of this study was to compare the effect of lower extremity ischemia reperfusion on the liver and the effect of ischemiareperfusion on the liver itself in a rat model. METHODS: Thirty Sprague-Dawley male rats were randomly divided into three groups including 10 in each group: sham (Group 1), lower limb ischemia-reperfusion (Group 2), and liver ischemia-reperfusion (Group 3). In Group 2, one hour of left lower limb ischemia was performed. In Group 3, one hour of ischemia in the liver was performed, followed by 24 hours of reperfusion. After reperfusion, the liver tissues were removed, and the groups were evaluated biochemically and histologically. RESULTS: The liver malondialdehyde levels were significantly higher in Groups 2 and 3 than in the sham group (p<0.001). In Group 2, the malondialdehyde levels were significantly higher than in Group 3 (p=0.019). The glutathione levels in the liver were significantly lower in Groups 2 and 3 than in the sham group (p<0.001). However, the glutathione levels were significantly higher in Group 2 than in Group 3 (p=0.005). In the histological evaluation, although the liver damage score was higher in Group 3 than in Group 2 (p=0.015), there was no significant difference between the two groups in TUNEL(+) cell number (p>0.05). CONCLUSION: Reperfusion injury in the liver after lower limb ischemiareperfusion is as important as ischemia-reperfusion injury which is specifically induced in the liver. This should be taken into account, particularly in reperfusion surgeries following vascular trauma or in cases of leg tourniquets to stop bleeding after lower limb vascular trauma.

Which Distant Organ is Most Affected by Lower Extremity Ischemia-Reperfusion?

BACKGROUND: It has been experimentally shown that reperfusion injury occurs in many remote organs after ischemia-reperfusion (I/R) of the lower extremity. However, which distant organ is affected more after I/R of the lower extremity has not been investigated. In this study, we investigate which remote organ is predominantly affected after lower extremity I/R. METHODS: Twenty male Sprague-Dawley rats were randomly divided into 2 groups: sham (group 1) and lower extremity I/R (group 2). In group 2, 1 hr of ischemia of the left lower extremity was followed by 24 hr of reperfusion of the limb. After reperfusion, the lung, liver, kidney, heart, and small intestine tissues were harvested in both groups. RESULTS: In the I/R group, the malondialdehyde levels were significantly higher in the heart and small intestine tissues than those in other tissues (P < 0.05). In addition, in the I/R group, the glutathione and glutathione peroxidase activities were also higher in the heart tissues than those in other tissues (P < 0.05). However, these results were not significant because the malondialdehyde, glutathione, and glutathione peroxidase levels of the heart tissues in the control group were higher than those of the other tissues. Therefore, no statistically significant difference was found between the tissues in terms of the histological damage score we created and the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling-positive cell numbers. CONCLUSIONS: There was no difference in the severity of reperfusion injury between the tissues we examined after lower extremity I/R. This suggests that every distal organ should be carefully monitored after lower extremity I/R.

Effects of Intraperitoneal Injection of Allogeneic Bone Marrow-derived Mesenchymal Stem Cells on Bronchiolitis Obliterans in Mice Model.

Bone marrow-derived mesenchymal stem cells (BMSCs) can ameliorate a variety of lung diseases such as asthma, lung fibrosis, and acute lung injury by its anti-inflammatory and immunmodulatory effects. In this study, we developed a mouse model of bronchiolitis obliterans (BO) and evaluated the effects of the intraperitoneal administration of BMSCs on lung histopathology and cytokine levels. 25 BALB/c mice were divided into four groups; control group (Group I), BO developed and 1x106 BMSCs-injected group (Group II), non-BO, 1x106 BMSCs-injected group (Group III), and BO developed and saline-injected group (Group IV). Histological and immunohistochemical findings of the lung tissue and the migration of BMSCs to the lung were evaluated using light and confocal microscopy techniques. Confocal microscopy evaluations showed that there was no noteworthy amount of BMSCs in the lung tissue of group III while significant amount of BMSCs was detected in group II. Wall thicknesses of terminal bronchiole and periterminal bronchiolar collagen deposition were significantly lower in group II compared to the group IV (p<0.05). Furthermore, according to the immunohistochemical staining results, CD3, CD4, CD8, CD20, CD68 and neutrophil elastase positive immune cells of group II were stained more positive than group IV cells (p<0.05). IFN-γ IL-2 and TNF-α levels in bronchoalveolar lavage fluid (BALF) were significantly lower in group II compared to group IV (p<0.05). The findings of this study indicate that intraperitoneally administered BMSCs have potent effects on histopatological changes of the lung tissue and cytokine levels in the murine model of BO.

Exercise increases leptin levels correlated with IGF-1 in hippocampus and prefrontal cortex of adolescent male and female rats.

It is known that regular aerobic exercise has positive effects on hippocampus and prefrontal cortex. We have previously have been able to demonstrate that aerobic exercise increased IGF-1 in hippocampus. Leptin, which is associated with cognitive functions, is also involved in fat metabolism and stimulates energy consumption. While it is known that leptin stimulates IGF-1 production in hepatocytes, little known is on the link between IGF-1 and leptin in brain during aerobic exercise. In this study, we investigated the effects of regular aerobic exercise on leptin, leptin receptor expression levels in hippocampus and prefrontal cortex. Additionally, we investigated the correlation of IGF-1 levels with leptin and leptin receptor expression. During the experiment, exercise group was run on a treadmill for 30min per session at a speed of 8m/min and 0° slope, five times a week for 6 weeks. Leptin, leptin expression, IGF-1 levels and cell numbers increased in prefrontal cortex and hippocampus of exercise groups. Blood leptin levels increased in female rats in exercise group; whereas it did not change in male rats; blood IGF-1 levels were found to be increased in exercised male rats. There was a strong positive correlation between hippocampal leptin levels and hippocampal IGF-1 levels; also a strong positive correlation between hippocampal leptin receptor expression and hippocampal IGF-1. These results indicate that, increased leptin and leptin receptor expression are correlated with IGF-1 in regular aerobic exercised rats. Blood leptin and IGF-1 levels were also found to be associated with gender. Females had high blood leptin levels and males had high blood IGF-1 levels in the exercise groups.

Intraperitoneal mesenchymal stem cell administration ameliorates allergic rhinitis in the murine model.

Previous studies showed that bone marrow-derived mesenchymal stem cells (BMSCs) could ameliorate a variety of immune-mediated and inflammatory diseases due to their immunomodulatory and anti-inflammatory effects. In this study, we developed a mouse model of ovalbumin (OVA) induced allergic inflammation in the upper airways and evaluated the effects of the intraperitoneal administration of BMSCs on allergic inflammation. Twenty-five BALB/c mice were divided into five groups; group I (control group), group II (sensitized and challenged with OVA and treated with saline-placebo group), group III (sensitized and challenged with OVA and treated with 1 × 106 BMSCs), group IV (sensitized and challenged with OVA and treated with 2 × 106 BMSCs), and group V (sensitized and challenged with phosphate buffered saline (PBS) and treated with 1 × 106 BMSCs). Histopathological features (number of goblet cells, eosinophils and mast cells, basement membrane, epithelium thickness, and subepithelial smooth muscle thickness) of the upper and lower airways and BMSCs migration to nasal and lung tissue were evaluated using light and confocal microscopes. Levels of cytokines in the nasal lavage fluid and lung tissue supernatants were measured using enzyme-linked immunosorbent assay (ELISA). Confocal microscopic analysis showed that there was no significant amount of BMSCs in the nasal and lung tissues of group V. However, significant amount of BMSCs were observed in group III and IV. In OVA-induced AR groups (group II, III, and IV), histopathological findings of chronic asthma, such as elevated subepithelial smooth muscle thickness, epithelium thickness, and number of goblet and mast cells, were determined. Furthermore, the number of nasal goblet and eosinophil cells, histopathological findings of chronic asthma, and IL-4, IL-5, IL-13, and NO levels was significantly lower in both BMSCs-treated groups compared to the placebo group. Our findings indicated that histopathological findings of chronic asthma were also observed in mice upon AR induction. BMSCs migrated to the nasal and lung tissues following intraperitoneal delivery and ameliorated to the airway remodeling and airway inflammation both in the upper and lower airways via the inhibition of T helper (Th) 2 immune response in the murine model of AR.

Protective Effect of Korean Red Ginseng on Cisplatin Ototoxicity: Is It Effective Enough?

OBJECTIVE: The aim of our study was to investigate the effects Korean Red Ginseng (KRG) on cisplatin (CDDP) ototoxicity in vivo and in vitro. MATERIALS AND METHODS: The first part of the study was conducted on the House Ear Institute-Organ of Corti 1 (HEI-OC1) cell line. Cells were treated with CDDP, KRG, and their combination for 24 h. Cell viability, apoptosis, and the expression of 84 apoptosis-related genes were analyzed. In the second part of the study, 30 Wistar albino rats were divided into five groups. Baseline distortion product otoacoustic emissions (DPOAEs) and auditory brainstem response (ABR) measurements were obtained. In groups I, II, and III, only saline, KRG, and CDDP, respectively, were given. In group IV, 500 mg/kg KRG and in group V, 150 mg/kg of KRG were administered for 10 days. In groups III, IV, and V, 16 mg/kg CDDP injections were administered on day 11. On day 14, final DPOAEs and ABR measurements were completed. The rats were then sacrificed, and their inner ear structures were evaluated by transmission electron microscopy. RESULTS: In the first part of the study, pretreatment with 1 mg/mL KRG protected cells from CDDP ototoxicity. This protection was mainly due to a decline in apoptotic gene expression and an increase in antiapoptotic gene expression. In the in vivo part of the study, we found that both KRG doses had otoprotective effects. This protection was more prominent at the lower dose, especially on the spiral ganglion and the brainstem. CONCLUSION: KRG was shown to be an otoprotective agent against CDDP-induced ototoxicity both in vivo and in vitro.

Effects of administration of subtoxic doses of acetaminophen on liver and blood levels of insulin-like growth factor-1 in rats.

Acetaminophen (APAP) is widely used in the treatment of pain. Toxic doses of APAP cause acute liver failure, but therapeutic doses are believed to be safe. The purpose of this study is to investigate the effects of administration of subtoxic doses of APAP on liver and blood levels of insulin-like growth factor-1 (IGF-1) in rats. Low dose (100 mg/kg) and high dose (250 mg/kg) of APAP were intraperitoneally injected into Wistar albino rats. Following administration of therapeutic doses of APAP, there were no significant changes in serum transaminases and liver glutathione levels. Both doses of APAP induced a decrease in liver and blood levels of IGF-1 when compared with the controls. There was no significant difference in liver IGF-1 levels between the high-dose and low-dose APAP groups; however, there was a significant difference in blood IGF-1 levels between both the groups. The histological examination showed that low dose of APAP induced mild degree of structural change, while high dose of APAP induced severe structural damage. In conclusion, these results suggest that blood IGF-1 levels may have a value in predicting hepatic damage resulting from therapeutic doses of APAP.

Protective Effect of Acetyl-L-Carnitine Against Doxorubicin-induced Cardiotoxicity in Wistar Albino Rats.

BACKGROUND AND AIMS: Anthracyclines are one of the most preferred agents in practical pediatric oncology despite their dose-dependent cardiotoxic effects. The aim of this study was to investigate whether or not acetyl-L-carnitine (ALCAR) has protective effects on doxorubicin (DOX)-induced cardiotoxicity. METHODS: Wistar rats were divided into four groups; control, DOX, ALCAR and ALCAR+DOX. Rats in the first group were given saline on study days, whereas those in the second group were given a single dose of DOX on the 5th day and saline on the other days. Rats in the third group were given ALCAR and those in the fourth group were given ALCAR on study days but also given only a single dose of DOX on the fifth day of the study. Ejection fractions (EF) were measured by echocardiography before and after drug administration. Heart tissues were evaluated by light and electron microscopy. Apoptotic cells were determined with TUNEL and caspase-3 staining. RESULTS: DOX significantly decreased the EF values, whereas ALCAR did not. Cardiac functions were higher in the ALCAR+DOX group when compared to the DOX group. DOX administration caused a cardiac injury not only functionally, but also structurally, whereas ALCAR prevented it. CONCLUSIONS: ALCAR has a capacity of preventing DOX-induced cardiac injury at both functional and structural levels.

Investigation of iron's neurotoxicity during cerebral maturation in the neonatal rat model of haemolysis.

INTRODUCTION: Haemolytic disease of newborns due to rhesus and AB0 incompatibility is encountered frequently in neonatal clinics and may lead to severe haemolysis. In this study, it is suggested that important amounts of iron released with haemolysis may have a toxic effect on the brain parenchymal tissue, and the severity of the toxic effect can be correlated with the maturation of the brain barrier systems. To demonstrate the accumulation and the neuro-toxic effects of free iron (Fe) in the brain an experimental haemolysis model with various maturation phases was performed. MATERIAL AND METHODS: The study was composed of 48 Wistar rats with the following ages: five days old (Group A), 10 days old (Group B), and 19 days old (Group C). Each group was divided into three experimental subgroups and three control groups. Experimental groups were treated with intraperitoneal 75 mg/kg/day phenyl hydrazine hydrochloride for haemolysis. RESULTS: We demonstrated that the blood brain barrier (BBB) is permeable in five-day-old newborn rats and is mature in 10- and 19-day-old rats. Iron staining and neuronal damage were detected in group A and group B rats. No damage was detected in the brain tissue of group C animals. The presence of iron staining and neuronal damage in group B with mature BBB may suggest the existence of other incomplete barrier systems different from BBB that lead to iron accumulation in the brain. CONCLUSIONS: Blood brain barrier has a partial role in Fe transport, and the alternative barrier systems may also be involved. It could be supposed that after maturation of all barrier systems, excessive Fe penetration to the brain cannot occur. Our findings showed that the toxic amounts of iron may penetrate into the brain parenchyma of newborns despite the BBB preservation and cause neuronal damage in newborns, but the mature brain is not affected by the same magnitude blood levels.

Is there a gender-related susceptibility for cisplatin ototoxicity?

Ototoxicity is a well-known side effect of cisplatin. Some genetic and non-genetic risk factors were described for cisplatin ototoxicity. Although there are some studies which point out a sex-related difference for cisplatin nephrotoxicity and neurotoxicity, sex-related differences for cisplatin ototoxicity have not been studied. The aim of this study is to reveal whether there is any gender-related difference for susceptibility to cisplatin ototoxicity in rats. Fourteen male, 14 female Wistar albino rats were divided into four groups; a female control, a male control, a female cisplatin and a male cisplatin group. Distortion Product Otoacoustic Emission and, Auditory Brainstem Response measurements were obtained. For the cisplatin groups 16 mg/kg of cisplatin was applied. On the 4th day audiological examinations were repeated. After killing, cochleae and brainstem tissues were evaluated by light and electron microscopy. The hearing of the female rat cisplatin group was found to have deteriorated more than the hearing of the male rat cisplatin group. Histopathological evaluation revealed more serious damage in the spiral ganglion and brainstem tissues of female rats. Hearing of female rats deteriorated more than the hearing of male rats upon application of cisplatin. This difference in hearing can be attributed to the more severe damage seen in neuronal tissues such as spiral ganglion cells and brainstem neurons.

Effects of inhaled L-arginine administration in a murine model of acute asthma.

Increased arginase activity in the airways decreases L-arginine and causes deficiency of bronchodilating and anti-inflammatory nitric oxide (NO) in asthma. As, it is suggested that L-arginine may have therapeutic potential in asthma treatment, we aimed to investigate the effects of inhaled L-arginine on oxygen saturation (SaO2) and airway histology in a murine model of acute asthma. Twenty eight BALB/c mice were divided into four groups; I, II, III and IV (control). All groups except the control were sensitized and challenged with ovalbumin. After establishement of acute asthma attack by metacholine administration, the mice were treated with inhaled L-arginine (Group I), saline (Group II) and budesonide (Group III), respectively. SaO2was measured by pulse oximeter just before and 5 min after methacholine. A third measurement of SaO2was also obtained 15 min after drug administration in these study groups. Inflammation in the lung tissues of the sacrificed animals were scored to determine the effects of the study drugs. The number of eosinophils in bronchoalveolar lavage (BAL) was determined. The results indicated that inflammatory scores significantly improved in groups receiving study drugs when compared with placebo and L-arginine was similar in decreasing scores when compared with budesonide. SaO2had a tendency to increase after L-arginine administration after acute asthma attack and this increase was statistically significant (p=0.043). Eosinophilia in BAL significantly reduced in group receiving L-arginine when compared with placebo (p<0.05). Thus in this study we demonstrated that L-arginine improved SaO2and inflammatory scores in an acute model of asthma.

Potential novel biomarkers for diabetic testicular damage in streptozotocin-induced diabetic rats: nerve growth factor Beta and vascular endothelial growth factor.

BACKGROUND: It is well known that diabetes mellitus may cause testicular damage. Vascular endothelial growth factor (VEGF) and nerve growth factor beta (NGF-ß) are important neurotrophic factors for male reproductive system. OBJECTIVE: We aimed to investigate the correlation between testicular damage and testicular VEGF and NGF-ß levels in diabetic rats. METHODS: Diabetes was induced by streptozotocin (STZ, 45 mg/kg/i.p.) in adult rats. Five weeks later testicular tissue was removed; testicular VEGF and NGF-ß levels were measured by ELISA. Testicular damage was detected by using hematoxylin and eosin staining and periodic acid-Schiff staining, and apoptosis was identified by terminal-deoxynucleotidyl-transferase-mediated dUTP nick end labeling (TUNEL). Seminiferous tubular sperm formation was evaluated using Johnsen's score. RESULTS: In diabetic rats, seminiferous tubule diameter was found to be decreased; basement membrane was found to be thickened in seminiferous tubules and degenerated germ cells. Additionally, TUNEL-positive cells were increased in number of VEGF+ cells and levels of VEGF and NGF-ß were decreased in diabetic testes. Correlation between VEGF and NGF-ß levels was strong. CONCLUSION: These results suggest that the decrease of VEGF and NGF-ß levels is associated with the increase of the apoptosis and testicular damage in diabetic rats. Testis VEGF and NGF-ß levels could be potential novel biomarkers for diabetes induced testicular damage.