Volkan Solmaz

Exenatide reduces TNF-α expression and improves hippocampal neuron numbers and memory in streptozotocin treated rats.

Recent studies suggest a possible link between type 2 diabetes and Alzheimers disease (AD). Glucogan-like peptide 1 (GLP-1) facilitates insulin release from pancreas under hyperglycemic conditions. In addition to its metabolic effects, GLP-1 and its long-lasting analogs, including exenatide can stimulate neurogenesis and improve cognition in rodent AD model. The aim of the present study was to investigate the effects of exenatide on hippocampal cellularity, cognitive performance and inflammation response in a rat model of AD. Fourteen rats were used to create AD model using intracerebroventricular (ICV) streptozotocin (STZ) infusion while 7 rats were administered 0.9% NaCl only (sham-operated group). Following stereotaxic surgery, STZ received rats were randomly distributed into two groups, and treated with either saline or exenatide 20 µgr/kg/day through intraperitoneally for two weeks. Then, cognitive performance (passive avoidance learning), brain tumor necrosis factor alpha (TNF-α) levels, choline acetyltransferase (ChAT) activity and hippocampal neuronal count were determined. While the brain TNF-α levels were significantly high in the saline-treated STZ group, exenatide treatment suppressed the increase in TNF-α levels. Saline-treated STZ group showed reduced ChAT activity compared to sham group. However, exenatide significantly preserved brain ChAT activity. The cognitive performance was also impaired in saline group while exenatide improved memory in rats. Moreover, exenatide treatment significantly prevented the decrease in hippocampal neurons. Overall, the results of the present study clearly indicated exenatide might have beneficial effects on impaired cognitive performance and hippocampal neuronal viability in AD by suppressing the inflammation response and increasing cholinergic activity.

Cholecalciferol (vitamin D 3) improves cognitive dysfunction and reduces inflammation in a rat fatty liver model of metabolic syndrome

AIM The aim of this study was to examine the effects of cholecalciferol on systemic inflammation and memory in the setting of fatty liver disease in rats. MATERIALS AND METHODS To induce the development of fatty liver disease, the rats were fed a 35% fructose solution over 8 weeks. Group I (n=6) was designated as the control group and fed with standard rat chow. Group II (n=6) was provided with, standard rat chow, and 0.3 μg/kg/day of oral cholecalciferol over a duration of 2 weeks. In addition to standard rat chow, group III (n=6) and group IV (n=6) were given 4 mL of the 35% fructose solution per day via oral gavage for 8 weeks. However, group IV was also given 0.3 μg/kg/day of oral cholecalciferol over 2 weeks. After the treatment period, passive avoidance tasks were performed by all groups. The liver and brain were harvested for subsequent biochemical and histopathologic analyses. KEY FINDINGS The development of fatty liver extends the memory latency period of passively avoiding tasks after 1 trial. Moreover, there were increases in brain TNF-α and plasma MDA levels according to two-way analysis of variance. Cholecalciferol supplementation decreased the latency period of passively avoiding tasks in rats with hepatosteatosis, and also significantly reduced brain TNF-α and plasma MDA levels. SIGNIFICANCE Fatty liver may contribute to the development of systemic inflammation, which affects cognition and causes deficits in memory; however, the anti-inflammatory and antioxidant properties of vitamin D may improve the cognitive function of rats with hepatosteatosis.

The neuroprotective effect of erythropoietin on experimental Parkinson model in rats.

Dopaminergic neuronal loss in Parkinsons disease (PD) results from oxidative stress, neuroinflammation and excitotoxicity. Because erythropoietin (EPO) has been shown to have antioxidant, anti-inflammatory and neuroprotective effects in many previous studies, present study was designed to evaluate the effect of EPO on rotenone-induced dopaminergic neuronal loss. The rats in which PD was induced by stereotaxical infusion of rotenone showed increased MDA and TNF-alpha levels and decreased HVA levels. On the other hand, EPO treatment resulted in markedly decreased MDA and TNF-alpha levels and increased HVA levels. EPO treatment in rotenone-infusion group resulted in improvement of striatal neurodegeneration and a significant increase in decreased total number of neurons and immunohistochemical TH positive neurons. Results of the present study demonstrate the neuroprotective, anti-inflammatory and antioxidant effects of EPO in a rotenone-induced neurodegenerative animal model.

Montelukast Inhibits Pentylenetetrazol-Induced Seizures in Rats

Background Montelukast is an antiinflammatory drug with an antioxidant property. In this study, we aimed to reveal whether montelukast has a preventive effect against seizures and post-seizure oxidative stress in pentylenetetrazol (PTZ)-induced seizures in rats. Material/Methods Of the 48 male Sprague-Dawley rats used in the study, 24 were assigned to EEG recordings (group A) and 24 were assigned to behavioral studies (group B). In group A, the electrodes were implanted on dura over the left frontal cortex for EEG recording. After 10 days, in group A, i.p. saline, 25, 50, or 100 mg/kg montelukast+35 mg/kg PTZ was administered to the rats. EEG was recorded and spike percentage was evaluated. In group B, i.p. saline, 25, 50, or 100 mg/kg montelukast+70 mg/kg PTZ was administered to the rats. Racine’s Convulsion Scale (RCS) and onset times of first myoclonic jerk (FMJ) was used to evaluate the seizures. Malondialdehyde (MDA) and superoxide dismutase (SOD) levels were determined in the brain tissue of animals. Results Animals treated with 50 or 100 mg/kg montelukast had significantly lower RCS and significantly increased FMJ onset time compared to the saline-treated animals. Moreover, groups given 25, 50, or 100 mg/kg montelukast had significantly lower MDA and higher SOD levels compared to the saline-treated group. The differences were more pronounced in the 100 mg/kg montelukast-pretreated group (p<0.001). Conclusions Montelukast showed anticonvulsant action and led to amelioration of oxidative stress markers in PTZ-induced seizures in rats.

Inhibitor effect of dexketoprofen in rat model of pentylenetetrazol-induced seizures

Objectives: The relationship between epilepsy and inflammation is known, and it has been reported that there is an increase in cyclooxygenase (COX) levels in epilepsy. We aim to reveal the anticonvulsant effects of dexketoprofen in pentylenetetrazol (PTZ)-induced seizures in rats. Materials and Methods: Forty-eight male Sprague-Dawley rats, 24 of them for EEG recording and 24 of them are for behavioral studies, were randomly divided in two groups: Group A for EEG recordings and Group B for behavioral assessment. A weight of 70 mg/kg PTZ was used for behavioral studies after dexketoprofen administration. Thirty-five milligrams per kilogram PTZ were used for EEG recording after dexketoprofen administration. The electrodes were implanted on dura over the left frontal cortex and the reference electrode was implanted over the cerebellum for EEG recording. The Racine convulsion scale (RCS), first myoclonic jerk (FMJ) onset time, and spike percentages were evaluated between the two groups. Results: There was a significant (P< 0·05) difference between the RCS, FMJ onset time (P< 0·001), and spike percentage (P< 0·05) between the groups (Group 2 compared with Groups 3 and 4). Conclusion: Dexketoprofen has an antiepileptic feature and this effect increases as the dosage increases, however it is currently unknown through which mechanism this drug shows its anticonvulsant effect. Dexketoprofen, in the group of NSAIDs, shows an anticonvulsant effect on PTZ-induced epilepsy model. This study suggests that dexketoprofen can preferably be used with NSAIDs for epileptic patients in clinical practice.

Clinical, demographic and prognostic features of sporadic amyotrophic lateral sclerosis in Northern Turkey

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease for which progression cannot be prevented. In this study, we evaluated 37 patients diagnosed with sporadic definitive-probable ALS who were monitored in our neurology clinic between 2002 and 2012 in terms of age, gender, profession, onset, and clinical course within the disease process. The hospital ethics committee approved the study. Nineteen female and 18 male patients diagnosed with sporadic definitive or probable ALS were evaluated for age, gender, level of education, residence, onset of disease, the time between the first symptom and diagnosis, and average lifetime after diagnosis. Twenty-eight of the patients had graduated from primary-secondary school, six were illiterate, and three of them were college graduates. Eighteen patients were living in city center, 19 were living in the country. Fourteen patients were farmers, 11 were housewives, and the remaining was working in various different occupations. The age of onset was 62.13. The men and women were diagnosed 10.27 months and 17.91 months after the first symptom, respectively (p = 0.001). The average survival time after diagnosis was 36.70 months for males and 49.80 months for females (p < 0.05). This difference was particularly evident among patients from rural areas. In addition, our female patients required interventions such as ventilation at a later period than did males. In conclusion, female gender seems to be one of the good prognostic factors for our ALS patients. This may be due to the protection by hormonal mechanisms in women or differences in their responses to exogenous toxins.

Neuroprotective Effects of Eexenatide in a Rotenone-Induced Rat Model of Parkinson’s Disease☆

Backround: Several studies suggest an association between Parkinsons disease (PD) and type 2 diabetes mellitus; these 2 diseases are both known to affect the common molecular pathways. As a synthetic agonist for the glucagon‐like peptide 1 receptor, exenatide has been evaluated as a neuroprotective agent in multiple animal models. Rotenone models of PD have great potential for the investigation of PD pathology and motor and nonmotor symptoms, as well as the role of gene‐environment interactions in PD causation and pathogenesis. Therefore, in this study, the neurochemical, behavioral and histologic effects of exenatide on a rotenone‐induced rat model of PD were examined. Materials and Methods: Eighteen adult male rats were randomly divided into the following 3 groups (n = 6): 1 group received stereotaxical infusion of dimethyl sulfoxide (vehicle, group 1) and the others received stereotaxical infusion of rotenone (groups 2 and 3). Apomorphine‐induced rotation test was applied to the rats after 10 days. Thereafter, group 2 was administered isotonic saline, whereas group 3 was administered exenatide for 28 days. Results: Malondialdehyde and tumor necrosis factor alpha levels increased in the rats with PD induced by rotenone, whereas malondialdehyde and tumor necrosis factor alpha levels markedly decreased in the rats treated with exenatide. The apomorphine‐induced rotation test scores of exenatide‐treated rats were determined to be lower compared with the untreated group. Additionally, treatment with exenatide significantly reduced the loss of dopaminergic neurons in striatum. Conclusions: These results have shown that exenatide has neuroprotective, anti‐inflammatory and antioxidant effects in a rotenone‐induced rat model of PD.

Neuroprotective effects of erythropoietin on Alzheimer’s dementia model in rats

BACKGROUND Although Alzheimers disease (AD) is the most common age-related neurodegenerative disease and characterized by memory impairment, only symptomatic treatments are available. OBJECTIVES Because recombinant human erythropoietin (rhEPO) has various neuroprotective effects and improves cognitive function in animal models of neurodegenerative disorders, we investigated the therapeutic effects of rhEPO in an intracerebroventricular (ICV)-streptozotocin (STZ) animal model of sporadic-AD. MATERIAL AND METHODS A total of 24 Sprague-Dawley adult rats were divided into 4 groups of naive control (n = 6), sham-operated (n = 6), ICV-STZ + saline (n = 6) and ICV-STZ + rhEPO (n = 6). Twelve rats with Alzheimers disease, induced by STZ injection (3 mg/kg) into both lateral ventricles using a stereotaxic frame (bilaterally ICV-STZ), were divided into 2 groups 5 days after the STZ injection: one treated with rhEPO 5000 (IU/kg/day, i.p.) and the other with 0.9% NaCl (1 mL/kg/day, i.p.) for 2 weeks. The sham-operated rats received bilaterally ICV-0.9% NaCl. No surgical operation or treatment was given to the naive-control animals. On day 20, a passive avoidance learning (PAL) test was used followed by sacrification and removal of the brain tissue in all animals. Brain TNF-α and ChAT levels were determined, and neurons in the hippocampal CA1 and CA3 regions were counted by Cresyl violet staining. RESULTS ICV-STZ was found to significantly shorten the latency time on the PAL, increase brain TNF-α level, and decrease brain ChAT activity and the number of neurons in the hippocampal CA1 and CA3 regions. On the other hand, rhEPO significantly attenuated all these detrimental effects induced by STZ. CONCLUSIONS RhEPO treatment significantly prevented the ICV-STZ-induced memory deficit by attenuating the hippocampal neuronal loss, neuroinflammation and cholinergic deficit in rats. This result suggests that rhEPO may be beneficial for treating AD.

Positive effects of ceftriaxone on pentylenetetrazol-induced convulsion model in rats

Aims: Many drugs have been associated with seizures as a side effect. Although they are defined as safe for nervous system. The effect on proconvulsant activity of beta lactam antibiotics have been also reported. We aimed to investigate whether ceftriaxone has an anticonvulsant effect on PTZ-induced seizures in rats. Materials and Methods: 36 male Sprague-Dawley rats, 18 of them for EEG recording and 18 of them are for behavioral studies, were randomly divided in two groups: group A for EEG recordings and group B for behavioral assesment. About 70 mg/kg PTZ was used for behavioral studies after Ceftriaxone administiration. About 35 mg/kg PTZ were used for EEG recording after ceftriaxone administiration. The electrodes were implanted on dura over the left frontal cortex and the reference electrode was implanted over the cerebellum for EEG recording. The Racine convulsion scale, first myoclonic jerk onset time, spike percentages, brain MDA and SOD levels were evaluated between the groups. Results: First myoclonic jerk onset time was significantly shorter in saline group than both 200 and 400 mg/kg ceftriaxone groups (p < 0.05). Racines convulsion scale was significantly lower in 200 and 400 mg/kg ceftriaxone groups than saline group (p < 0.01, p < 0.0001). Both of two ceftriaxone groups have lower spike percentages than the saline group (p < 0.05). Significantly lower MDA levels and higher SOD activity were determined in 200 mg/kg ceftriaxone group compared with the saline group (p < 0.05). Conclusion: Our study demonstrated that ceftriaxone has protective effects on PTZ-induced convulsions and on oxidative damage associated with PTZ.

Hypokalemia and hypomagnesaemia related to levetiracetam use

Levetiracetam (LEV), used for both partial and generalized seizures, is a frequently preferred antiepileptic because of its few side effects. We present a 23-year-old man who developed hypokalemia after switching from valproate to LEV. The patient was sent to our clinic due to hypokalemia 1 month after initiation of LEV, and his neurological examination was normal. Further examinations revealed hypokalemia (3.1 mmol/L) and hypomagnesaemia (0.56 mmol/L). His hemogram, blood urea nitrogen, creatinine, total cortisol, thyroid function tests, creatinine clearance, and renal Doppler ultrasound were normal. LEV was tapered off and treatment with 200mg/day lamotrigine begun. Potassium and magnesium levels returned to normal ranges in subsequent tests. While hypokalemia and hypomagnesaemia have not been reported before to our knowledge, interstitial nephritis and renal failure after the use of LEV have been. Hypokalemia, found in the early period in this case, may be an indicator of a recently developed renal tubular disorder. This experience indicates that unpredictable side effects of increasingly used new antiepileptic drugs should be taken into consideration.