فهرست مطالب
Basic and Clinical Neuroscience
Volume:11 Issue: 3, May-Jun 2020
- تاریخ انتشار: 1399/03/20
- تعداد عناوین: 13
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Pages 251-260Introduction
The underlying mechanism responsible for the cardiovascular response to hemorrhage (HEM) is still unknown; however, several brain areas, such as the cuneiform nucleus (CnF) have shown to be involved. In this study, the cardiovascular effect of the CnF during HEM was evaluated.
MethodsThe animals were divided into the following groups: 1. Vehicle; 2. HEM; 3. Cobalt chloride (CoCl2); 4. CoCl2+saline; and 5. CoCl2+HEM. Catheterization of the left and right femoral artery was performed to record blood pressure and blood withdrawal, respectively. Saline and CoCl2 were microinjected into the CnF nucleus, and then blood withdrawal was done for HEM induction. Cardiovascular regulation throughout the experiments was recorded and changes (∆) in the Systolic Blood Pressure (SBP), Mean Arterial Pressure (MAP) and Heart Rate (HR) were calculated over time and compared with those treated with saline and HEM, using repeated-measures ANOVA.
ResultsHEM significantly reduced ∆SBP and ∆MAP and augmented ∆HR than the vehicle group. CoCl2 did not significantly affect basic ∆SBP, ∆MAP, and ∆HR compared with the vehicle group. However, injection of CoCl2 into the CnF before HEM (CoCl2+HEM group) significantly decreased ∆SBP, ∆MAP, and tachycardia, induced by HEM.
ConclusionOur results indicated that blockade of the CnF by CoCl2 significantly reduced the hypotension and tachycardia, induced by HEM indicating the involvement of CnF in cardiovascular regulation during HEM.
Keywords: Hemorrhage, Cobalt chloride, Cuneiform nucleus, Midbrain Reticular formation, Heart Rate, Blood pressure -
Pages 261-268Introduction
Sleep deprivation can cause hyperalgesia and interfere with analgesic treatments. The aim of the present study was to establish an obligatory sleep-abstinence model and also evaluate the effects of intracerebroventricular (ICV) injection of crocin on pain perception in Wistar rats.
MethodsIn this experimental study, 35 adult male Wistar rats were randomly divided into 5 groups (n=7). The intra-ventricular cannulation was done for all rats before sleep deprivation. Sleep deprivation was performed by placing animals on a chamber equipped with an automatic animated conveyor (5 s with an interval of 3 min) for 72 h. Subsequently, the sleep-deprived animals received ICV injection of saline (MOD), Morphine 10 µg (MOR), Crocin 10 ug (Cr10), and Crocin40 µg (Cr40) using a microsyringe. Besides, a non-sleep-deprived group was allocated as a Control Group (NC) and only received an ICV injection of saline. Fifteen minutes after the ICV injections, pain perception was evaluated by the hot plate test (54±0.4◦C).
ResultsCompared with the NC group, latency significantly decreased in the MOD group (6.28±0.48 vs. 4.28± 0.48, p<0.0001). In comparison with the MOD group, both morphine (8.42±1.53) and crocin (7.60±1.45 for Cr10 and 8.14±0.89 for Cr40) could significantly increase latency in the sleep-deprived animals (p<0.0001). There was no statistically significant difference between the Cr10 and Cr40 (p=0.42), Cr10, and MOR (p=0.059) and Cr40 with MOR (p=0.86) groups.
ConclusionOur results indicated that crocin could attenuate hyperalgesia induced by sleep deprivation in rats.
Keywords: Secondary insomnia, Pain, Crocin, Analgesic -
Pages 269-278Introduction
Ethanol is considered as an effective agent in reducing brain stroke injury. In this study, we assessed the effects of modafinil along with ethanol as a combination therapy on behavioral function in Wistar rats.
MethodsThe right Middle Cerebral Artery Occlusion (MCAO) was performed and the rats were divided into nine groups (n=8 per group). The animal groups in this study were as follows: 1. MCAO control group (ischemia without treatment); 2. vehicle group; 3. modafinil group that was randomly subdivided into three groups receiving different doses of modafinil (10, 30, and 100 mg/kg) for 7 days before MCAO; 4. ethanol group receiving 1.5 g/kg ethanol at the time of reperfusion; 5. modafinil + ethanol group that was further subdivided into three groups receiving modafinil at different doses (10, 30, and 100 mg/kg) for 7 days before MCAO and ethanol at the time of reperfusion. The motor behavior was measured using the Garcia test 24, 48, and 72 h after the ischemia, and the elevated body swing test was performed 48 and 72 h after the ischemia. The anxiety and locomotor activity were analyzed by open field test 48 and 72 h post-ischemia.
ResultsThe results showed that the neurological deficit score, locomotor activity, and unexpected thigmotaxis (anxiety) in the ethanol, modafinil (in a dose-dependent manner), and ethanol+modafinil treatment groups were significantly higher than the MCAO control group.
ConclusionIt seems that the combination therapy of modafinil (100 mg/kg) and ethanol (1.5 g/kg) significantly enhanced neuroprotection via an improvement in locomotor activity and neurological functions.
Keywords: Middle cerebral artery, Ethanol, Neuroprotection, Locomotion, Anxiety -
Pages 279-288Introduction
This research investigated the effects of violent and football video games on cognitive functions, cortisol levels, and brain waves.
MethodsA total of 64 participants competed in a single-elimination tournament. Saliva samples of all players were obtained before and after the games for the assessment of cortisol levels. The cognitive performances of the players were also assessed by paced auditory serial addition test. Moreover, the electroencephalogram recording was conducted during the games.
ResultsThe results showed that salivary cortisol levels significantly decreased after playing both games. Also, playing the football game increased reaction time, whereas decreased sustained attention and mental fatigue.
ConclusionConversely, following playing a violent game, the reaction time decreased, and sustained attention and mental fatigue increased. Furthermore, the results of the EEG recording revealed that playing a violent game engaged more brain regions than the football game. In conclusion, playing violent game more effectively improved cognitive performances in the players than the football game.
Keywords: Cognitive, Cortisol, PASAT, Football game, EEG, Violent game -
Pages 289-300Introduction
Curcumin, a yellow-pigment, found in the popular Indian spice turmeric (Curcuma longa), poses pharmaceutical applications due to its anti-inflammatory, antioxidant, and chemoprotective properties. Excessive fluoride causes fluorosis leading to neurodegeneration and associated behavioral deficits, particularly in children. This study aimed at investigating the neuroprotective ability of curcumin on sodium fluoride (NaF)-related alterations of acetylcholine, catecholamines, histological changes in hippocampus and behavior of rats exposed to NaF during pre- and post-natal period.
MethodsPregnant albino Wistar rats were chosen and divided into four groups. The experimental period lasted 53 days (i.e. the gestational period of 23 days and post-gestational period of 30 days), at which the control group received normal tap water, the experimental group received NaF (20 ppm/kg bw) through drinking water, and the protective groups received curcumin (10 mg and 20mg/kg bw) by gavage and NaF (20 ppm/kg bw) through drinking water. Behavioral study (open field test) was done using postnatal pups aged 21 and 30 days. The brains of postnatal pups aged 1, 7, 14, 21, and 30 days were collected and used for biochemical analysis and those of pups aged 14, 21, and 30 days were used for histopathological analysis.
ResultsNaF-exposed rats showed a significant (p<0.05) decrease in body weight, brain weight, and behavioral activities, which were significantly reversed with curcumin treatment. The levels of epinephrine significantly (p<0.05) increased, whereas norepinephrine, dopamine and acetylcholine levels declined in NaF-treated group compared with the control group, which were significantly (p<0.05) reversed after treatment by curcumin (10 mg/kg bw and 20 mg/kg bw) along with NaF. The histological alterations, including shrinkage of neurons and nissal substances were observed in the hippocampus of NaF-treated pups that the control pups, whereas co-treatment with curcumin and NaF showed ameliorative effects and controlled the histological alterations.
ConclusionThe results showed the neuroprotective effect of curcumin on behavior, neurotransmitter levels, and histological changes in the hippocampus against NaF-induced neurotoxicity in developing rat pups.
Keywords: Curcumin, Sodium fluoride, Neurotransmitters, Hippocampus, Behavior -
Pages 301-312Introduction
The neural substrates of temporal processing are not still fully known. The majority of interval timing studies have dealt with this subject in the context of “Explicit timing” (computing the time intervals explicitly). The hypothesis “Implicit timing” (implicitly using temporal processing to improve function) has also proposed. This lesion study addressed explicit and implicit timing paradigms simultaneously using identical experimental tasks.
MethodsIn this case-control study, 15 patients with Right Hemisphere Damage (RHD) and 15 patients with Left Hemisphere Damage (LHD) and 15 age-matched normal subjects were included. Participants performed a temporal reproduction task (assessing explicit timing) and a temporal prediction task (assessing implicit timing) in two sub- and supra-second intervals.
ResultsOur results showed that RHD can lead to significantly lower accuracy in the temporal reproduction task in sub-second (p=0.005) and supra-second (p=0.001) intervals, compared with the normal subjects. Also, LHD led to perturbation in temporal prediction task by an increase in reaction time (lower accuracy) in sub- (p=0.011) and supra-second (p=0.006) time intervals than the normal subjects.
ConclusionOverall, our findings suggested that there is a right hemispheric bias in the neural substrate of explicit timing, in both sub- and supra-second intervals. Furthermore, for the first time in a lesion study, we showed the evidence of left-hemispheric bias in neural substrates of implicit timing.
Keywords: Lesion study, Interval timing, Explicit timing, Implicit timing -
Pages 313-322Introduction
Recent studies have identified Attention Deficit Hyperactivity Disorder (ADHD) as an inflammatory condition associated with immunological and oxidative responses. Therefore, it is necessary to examine these processes in these patients. The present study aimed at investigating the relationship between the dietary intake of antioxidants, Superoxide Dismutase (SOD) activity, and the serum levels of inflammatory factors in ADHD students.
MethodsThis retrospective case-control study was conducted on 64 ADHD children aged 6 - 13 years. The demographic questionnaire, Food Frequency Questionnaire, and Baecke Physical Activity Questionnaire were used for data collection. SOD activity and the serum level of inflammatory factors (homocysteine, interleukin-6, and C-reactive protein (CRP)) were measured in all patients. According to the CRP values, 32 patients were included in the case group (CRP≥1 mg/L) and 32 patients in the control group (0≤CRP<1 mg/L).
ResultsThere was no significant difference between the two groups in age, sex, weight, height, and body mass index. In the case group, the mean SOD activity (P=0.034), the physical activity (P=0.04), zinc intake (P=0.02), and homocysteine levels were higher than the control group (P=0.001). Of all studied variables, the best predictors were homocysteine (OR: 1.34, 95% CI: 1.082-1.670, P=0.029) and physical activity (OR: 0.85, 95% CI: 0.761-0.952, P=0.022) respectively, whereas other variables were not significant predictors.
ConclusionThe present study showed that the level of inflammatory factors in the case group was significantly higher than the control group. Homocysteine and physical activity can predict the inflammation status induced by CRP.
Keywords: Antioxidants, Inflammation, C-Reactive protein, Attention Deficit Disorder with Hyperactivity, Child -
Pages 323-332Introduction
In stroke models, Inducible Nitric Oxide Synthase (iNOS) expression initiates cellular toxicity due to excessive Nitric Oxide (NO) generation. Anchusa italica is a medicinal herb with anti-inflammatory, antioxidant and neuroprotective properties. This study evaluated the antioxidant activity and NOS mRNA expression of the Hydroalcoholic Extract Of Anchusa Italica (HEAI) in an experimental stroke model in rats.
MethodsThe stroke model was induced by bilateral occlusion of both common carotid arteries for 60 min. Twenty-four hours after surgery, HEAI (50 and 100 mg/kg i.p.) was injected daily for 10 consecutive days. mRNA expression levels of NOS subtypes and hippocampal Brain-Derived Neurotrophic Factor (BDNF) were studied using real-time PCR. Besides, hippocampal tissue plus serum concentrations of NO and malondialdehyde (MDA) were measured.
ResultsHEAI decreased MDA in both serum and hippocampal tissue and also reduced serum NO levels. Additionally, in the HEAI-treated groups, a down-regulation of iNOS mRNA expression, and an up-regulation of BDNF mRNA expression were observed.
ConclusionThe results indicated that the administration of HEAI even after the onset of ischemia protects the brain from free radical injury and inflammation via a down-regulation of iNOS expression inhibiting NO production and an up-regulation of BDNF mRNA.
Keywords: Anchusa italica, Ischemia-reperfusion, Nitric oxide, Stroke -
Pages 333-348Introduction
In this study, the role of A1 adenosine receptors in improving the effect of Low-Frequency Electrical Stimulation (LFS) on seizure-induced hyperexcitability of hippocampal CA1 pyramidal neurons was investigated.
MethodsA semi-rapid hippocampal kindling model was used to induce seizures in male Wistar rats. Examination of the electrophysiological properties of CA1 pyramidal neurons of the hippocampus using whole-cell patch-clamp recording 48 h after the last kindling stimulation revealed that the application of LFS as two packages of stimulations at a time interval of 6 h for two consecutive days could significantly restore the excitability CA1 pyramidal neurons evidenced by a decreased in the of the number of evoked action potentials and enhancement of amplitude, maximum rise slope and decay slope of the first evoked action potential, rheobase, utilization time, adaptation index, first-spike latency, and post-AHP amplitude. Selective locked of A1 receptors by the administration of 8-Cyclopentyl-1,3-dimethylxanthine (1 μM, 1 μl, i.c.v.) before applying each LFS package, significantly reduced LFS effectiveness in recovering these parameters.
ResultsOn the other hand, selective activation of A1 receptors by an injection of N6-cyclohexyladenosine (10 μM, 1 μl, i.c.v.), instead of LFS application, could imitate LFS function in improving these parameters.
ConclusionIt is suggested that LFS exerts its efficacy on reducing the neuronal excitability, partially by activating the adenosine system and activating its A1 receptors.
Keywords: Seizure, Kindling, Low-frequency stimulation, Electrophysiological Properties, Adenosine A1 Receptors -
Pages 349-358Introduction
Klotho and dipeptidyl peptidase-4 (DPP4) are two proteins that modulate inflammatory pathways. We investigated the association between circulating klotho and DPP4 activity and their relationship with inflammatory cytokines, miR-29a, and miR-195 in Alzheimer disease (AD).
MethodsThis study was conducted on 16 AD patients and 16 healthy age-matched controls. Plasma levels of tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β, interleukin-6 (IL-6), klotho, and DPP4 were measured by enzyme-linked immunosorbent assay. Plasma expression of miR-29a and miR-195 were also measured and compared by a real-time polymerase chain reaction.
ResultsThere was a significant increase in TNF-α (p=0.006), IL-1β (p=0.012), and IL-6 (p=0.012) levels in the AD subjects compared with controls. Also, we found a decrease in plasma levels of klotho and an increase in plasma levels of DPP4 in the AD group that was not significant compared with the controls. Lower expression of miR-29a (P=0.009) and higher expression of miR-195 (P=0.003) were observed in the AD group that was significant than controls. Further analysis showed a negative correlation between klotho and plasma levels of IL-6 (r=-0.58, p=0.01). Also, there was a positive correlation between plasma DPP4 activity and TNF-α levels (r=0.50, P=0.04) and IL-1β (r=0.62, P=0.01). Likewise, plasma klotho concentration showed a negative correlation with the age of AD subjects (r=-0.56, P=0.02).
ConclusionTNF-α, IL-1β, and IL-6 are involved in AD pathophysiology, and dysregulation of DPP4 and klotho may be associated with the inflammatory response of AD. Down-regulation of miR-29a and up-regulation of miR‑195 indicated the role of miRNAs in the AD process.
Keywords: Alzheimer Disease (AD), Klotho, Dipeptidyl Peptidase-4, Inflammatory cytokines, MicroRNAs -
Pages 359-368Introduction
Attention-Deficit/Hyperactivity Disorder (ADHD) is a well-known neurodevelopmental disorder. Diagnosis and treatment of ADHD can often lead to a developmental trajectory toward positive results. The present study aimed at implementing the decision tree method to recognize children with and without ADHD, as well as ADHD subtypes.
MethodsIn the present study, the subjects included 61 children with ADHD (subdivided into ADHD-I (n=25), ADHD-H (n=14), and ADHD-C (n=22) groups) and 43 typically developing controls matched by IQ and age. The Child Behavior Checklist (CBCL), Integrated Visual And Auditory (IVA) test, and quantitative EEG during eyes-closed resting-state were utilized to evaluate the level of behavioral, neuropsychology, and electrophysiology markers using a decision tree algorithm, respectively.
ResultsBased on the results, excellent classification accuracy (100%) was obtained to discriminate children with ADHD from the control group. Also, the ADHD subtypes, including combined, inattention, and hyperactive/impulsive subtypes were recognized from others with an accuracy of 80.41%, 84.17%, and 71.46%, respectively.
ConclusionOur results showed that children with ADHD can be recognized from the healthy controls based on the neuropsychological data (sensory-motor parameters of IVA). Also, subtypes of ADHD can be distinguished from each other using behavioral, neuropsychiatric and electrophysiological parameters. The findings suggested that the decision tree method may present an efficient and accurate diagnostic tool for the clinicians.
Keywords: ADHD subtypes, Behavior, Neuropsychology, Electrophysiology, Decision tree -
Pages 369-378Introduction
This study was designed to investigate the possible anticonvulsant effect of acute administration of an aqueous extract of flowers of Alcea aucheri (EFA) in a seizure model.
MethodsSeizures were induced in male adult Swiss mice by administration of pentylenetetrazol (PTZ) or Maximal Electroshock (MES). Mice were randomly subjected to receive saline, EFA (8.75-175 mg.kg-1), or diazepam intraperitoneally (i.p.) 15 or 30 min before PTZ injection. In another experiment, mice were treated (i.p.) with saline, EFA (8.75-350 mg.kg-1), or phenytoin 15 or 30 min before the MES test. Diazepam and phenytoin were used as reference drugs.
ResultsEFA (175 mg.kg-1) significantly increased the PTZ-induced seizure threshold compared with the saline control group 15 min after administration. In the MES test, the extract (35 mg.kg-1) increased the latency to onset of tonic Hind Limb Extension (HLE) (seizure activity) compared with the saline group 15 min after treatment. Also, 30 min after treatment, EFA (35, 70, and 175 mg.kg-1) increased the latency to onset of the seizure, decreased the duration of the seizure (70 mg.kg-1), and decreased seizure occurrence (350 mg.kg-1) compared with those of the saline group. At both time points, the extract at all doses significantly reduced the mortality rate compared with the saline group.
ConclusionThese findings provide evidence of a possible anticonvulsant effect of A. aucheri in PTZ and MES seizure models in mice
Keywords: Alcea aucheri, Pentylenetetrazole, Seizure threshold, Maximal electroshock seizure, Mice -
Pages 379-380
We read with interest the article by Almasi et al. on a 48 years old female patient with Mitochondrial Encephalomyopathy, Lactic Acidosis, And Stroke-like episodes (MELAS), diagnosed based on the clinical presentation, blood test results, and imaging and muscle biopsy findings . We have the following comments and concerns.