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Huntington's disease (HD) is a scarce neurodegenerative disorder defined by chorea (unusual involuntary movements), behavioral presentations, psychiatric features, and cognitive deterioration. Although the precise pathogenic mechanism behind HD has not yet been identified, the most widely acknowledged pathways include excitotoxicity, mitochondrial malfunction, neuroinflammation, neurochemical imbalance, oxidative stress, and apoptosis HD has no efficient therapy. Current medications have drawbacks. Silymarin, a compound made up of standardized extracts obtained from the seeds of the Silybum marianum and polyphenolic flavonolignan, is utilized in therapeutic settings to treat a variety of experimental disorders in animals. Silymarin's key pharmacological activities include anti-cancer, hepatoprotection, antioxidant, cardioprotection, and anti-inflammatory. It also has no adverse side effects on people or animals. The current study aims to provide Silymarin's neuro-pharmacological activities or therapeutic qualities in HD. In this study, Thirty-six male Sprague-Dawley rats (200-220g, 8 weeks) at the initial of the study were used. Silymarin solution (100mg/Kg) was administered by oral gavage for 21 days to ameliorate neural damage in rats injected with 3-nitropropionicacid (3-NP) in a preliminary rat model of HD. The results showed that administration of silymarin to HD rats reduced gliosis, improved motor coordination and muscle activity, and increased striatal volume and the number of neurons and glial cells. Our results suggest that silymarin provides a protective environment for nerve cells and can have beneficial effects against the harmful effects of HD.
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Gallic acid (GA) is known to be a natural phenolic compound with antioxidant and neuroprotective effects. This study aims to investigate the impact of GA against restraint stress-induced oxidative damage, anxiety-like behavior, neuronal loss, and spatial learning and memory impairment in male Wistar rats. The animals were divided into four groups (n = 8) and subjected to restraint stress for 4 h per day for 14 consecutive days or left undisturbed (control without inducing stress). In the treatment group, the animals were treated with 2 mL normal saline plus 100 mg/kg GA per day for 14 consecutive days (STR + GA group). The animals received the drug or normal saline by gavage 2 h before inducing restraint stress. ELISA assay measured oxidative stress factors. Elevated-plus maze and Morris water maze tests assessed anxiety-like behavior and spatial learning and memory, respectively. Also, neuronal density was determined using Nissl staining. Restraint stress significantly increased MDA and reduced the activities of GPX and SOD in the stressed rats, which were reserved by treatment with 100 mg/kg GA. Restraint stress markedly enhanced the anxiety-like behavior and spatial learning and memory impairment that were reserved by GA. In addition, treatment with GA reduced the neuronal loss in the stressed rats in the hippocampus and prefrontal cortex (PFC) regions. Taken together, our findings suggest that GA has the potential to be used as a good candidate to attenuate neurobehavioral disorders as well as neuronal loss in the hippocampus and PFC induced by restraint stress via reducing oxidative damage.
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Ácido Gálico , Solução Salina , Ratos , Masculino , Animais , Ácido Gálico/farmacologia , Ácido Gálico/uso terapêutico , Ratos Wistar , Solução Salina/farmacologia , Estresse Oxidativo , Córtex Pré-Frontal , Hipocampo , Transtornos da MemóriaRESUMO
BACKGROUND: For years, numerous studies have focused on identifying approaches to increase insulin sensitivity by modifying the signaling factors. In the present study, we examined the effects of Eryngium billardieri extract, as an anti-diabetic herbal medication, on the heart mRNA level of Akt serine/threonine kinase (Akt), mechanistic target of rapamycin kinase (mTOR), peroxisome proliferator-activated receptor gamma (PPARγ), and Forkhead box o1 (Foxo1) in rats with high-fat diet (HFD)-induced insulin resistance (IR). We also assessed the anti-diabetic effects of E. billardieri extract in rats with insulin resistance. METHODS: Twenty-seven male Wistar rats were divided into two groups. Nine rats were fed a normal diet (control group), and 18 rats were fed an HFD for 13 weeks (HFD group). To confirm the induction of insulin resistance, the oral glucose tolerance test (OGTT) was performed and homeostatic model assessment for insulin resistance (HOMA-IR) was calculated. Then rats with IR were randomly divided into the following groups: the HFD group, which continued an HFD, and the group treated with E. billardieri extract, which received the extract at a concentration of 50 mg/kg for 30 days. On the 30th day, the animals were sacrificed and serum samples were collected for biochemistry analyses. Furthermore, the expression of Akt, mTOR, PPARγ, and Foxo1 was measured in heart tissue using the real-time polymerase chain reaction (PCR) method. RESULTS: Real-time PCR analyses revealed that an HFD can significantly decrease the expression level of Akt, mTOR, and PPARγ in the heart tissue. However, an HFD significantly increased the expression level of Foxo1 in the HFD group compared to the control group (P < 0.05). In addition, our data showed that the administration of E. billardieri extract significantly enhanced the mRNA levels of Akt, PPARγ, and mTOR in the heart tissue compared to the HFD group (P < 0.05), while it significantly decreased the Foxo1 mRNA levels (P < 0.01). CONCLUSION: Given that Akt, mTOR, PPARγ, and Foxo1 are critical factors in insulin resistance, the present study suggests that E. billardieri could probably be used as an alternative treatment for IR as a major feature of metabolic syndrome.
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Eryngium , Resistência à Insulina , Ratos , Masculino , Animais , Eryngium/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , PPAR gama/genética , Ratos Wistar , RNA Mensageiro , Serina-Treonina Quinases TOR/genética , Expressão GênicaRESUMO
BACKGROUND: Due to the complications related to the use of the current pharmacological approach for the alleviation of neuropathic pain, searching for effective compound with fewer complications is a requirement of the present era. It is well known that the pathophysiological mechanism of neuropathic pain is related to excessive inflammation in the nervous system. Hence, the present study focuses on whether the potential analgesic effects of Terminalia chebula (TC) extract are mediated by the changes in the protein expression of nerve growth factor (NGF) and nuclear factor-kappa B (NF-κB) in the brain in a rat model of sciatic nerve chronic constriction injury (CCI). METHOD AND RESULTS: Neuropathic pain was induced by the left sciatic nerve CCI. Male Wistar rats were assigned to three groups: sham, CCI, and CCI + TC (40 mg/kg). Animals received either normal saline (1 mL) or the aqueous-alcoholic extract of TC (40 mg/kg) for 30 days via gavage needles once a day. Cold allodynia and anxiety-like behaviors were examined one day before CCI surgery (day - 1), as well as days 2, 7, 14, and 30 following CCI. We also assessed the effects of the TC extract oxidative stress markers on day 30 following CCI. Moreover, a western blot analysis was performed on day 30 following CCI to evaluate the effects of the TC extract on the protein expression of NGF and NF-κB in the brain. Oral gavage of the TC extract significantly decreased cold allodynia on days 2 and 14 following CCI. Additionally, the CCI model of chronic pain significantly increased the protein expression of NGF and NF-κB in the brain on day 30 following CCI. Furthermore, the TC extract significantly decreased the protein expression of NGF and NF-κB in the brain. The TC extract also significantly increased the brain glutathione (GSH) content and decreased the malondialdehyde (MDA) content. CONCLUSION: It is suggested that the analgesic effects of the TC extract are mediated by the suppression of brain NGF, NF-κB, and by its antioxidant activity in the brain following neuropathic pain in rats.
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Neuralgia , Neuropatia Ciática , Ratos , Animais , Masculino , NF-kappa B/metabolismo , Hiperalgesia/tratamento farmacológico , Fator de Crescimento Neural/genética , Fator de Crescimento Neural/metabolismo , Fator de Crescimento Neural/farmacologia , Ratos Sprague-Dawley , Ratos Wistar , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Biomarcadores/metabolismo , Analgésicos/farmacologia , Analgésicos/metabolismo , Encéfalo/metabolismo , Estresse Oxidativo , Nervo Isquiático/lesõesRESUMO
Tramadol is a synthetic analogue of codeine and stimulates neurodegeneration in several parts of the brain that leads to various behavioral impairments. Despite the leading role of hippocampus in learning and memory as well as decreased function of them under influence of tramadol, there are few studies analyzing the effect of tramadol administration on gene expression profiling and structural consequences in hippocampus region. Thus, we sought to determine the effect of tramadol on both PC12 cell line and hippocampal tissue, from gene expression changes to structural alterations. In this respect, we investigated genome-wide mRNA expression using high throughput RNA-seq technology and confirmatory quantitative real-time PCR, accompanied by stereological analysis of hippocampus and behavioral assessment following tramadol exposure. At the cellular level, PC12 cells were exposed to 600 µM tramadol for 48 hrs, followed by the assessments of ROS amount and gene expression levels of neurotoxicity associated with neurodegenerative pathways such as apoptosis and autophagy. Moreover, the structural and functional alteration of the hippocampus under chronic exposure to tramadol was also evaluated. In this regard, rats were treated with tramadol at doses of 50 mg/kg for three consecutive weeks. In vitro data revealed that tramadol provoked ROS production and caused the increase in the expression of autophagic and apoptotic genes in PC12 cells. Furthermore, in-vivo results demonstrated that tramadol not only did induce hippocampal atrophy, but it also triggered microgliosis and microglial activation, causing upregulation of apoptotic and inflammatory markers as well as over-activation of neurodegeneration. Tramadol also interrupted spatial learning and memory function along with long-term potentiation (LTP). Taken all together, our data disclosed the neurotoxic effects of tramadol on both in vitro and in-vivo. Moreover, we proposed a potential correlation between disrupted biochemical cascades and memory deficit under tramadol administration.
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Analgésicos Opioides/toxicidade , Hipocampo/efeitos dos fármacos , Memória , Tramadol/toxicidade , Animais , Apoptose , Autofagia , Hipocampo/metabolismo , Hipocampo/fisiologia , Potenciação de Longa Duração , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Células PC12 , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismoRESUMO
This study aimed to find out cellular and electrophysiological effects of the edaravone (EDR) administration following induction of vascular dementia (VaD) via bilateral-carotid vessel occlusion (2VO). The rats were randomly divided into control, sham, 2VO + V (vehicle), and 2VO + EDR groups. EDR was administered once a day from day 0-28 after surgery. The passive-avoidance, Morris water-maze, and open-field tests were used for evaluation of memory, locomotor, and anxiety. The field-potential recording was used for assessment of electrophysiological properties of the hippocampus; and after sacrificing, the cerebral hemispheres were removed for stereological study and evaluation of MDA levels. The long-term potentiation (LTP), paired-pulse ratio (PPR), and input-output (I/O) curves were evaluated as indexes for long-term and short-term synaptic plasticity, and basal-synaptic transmission (BST), respectively. The 2VO led to increases in MDA level with considerable neuronal loss and decreases in the volume of the hippocampus, along with a reduction in the BST and LTP induction which was associated with a decrement in PPR and ultimate loss in memory with higher anxiety behavior. However, administration of EDR caused a decline in MDA and prevented the neural loss and volume of the hippocampus, rescued BST and LTP depression, improved memory and anxiety without any effects on PPR. Therefore, most likely through the improvement of MDA level, and the hippocampal cell number and volume, EDR leads to recovery of synaptic plasticity and behavioral performance. Because of the LTP rescue, without recovery of PPR, it is likely that the EDR improved LTP through the post-synaptic neurons.
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Demência Vascular/tratamento farmacológico , Edaravone/uso terapêutico , Sequestradores de Radicais Livres/uso terapêutico , Hipocampo/patologia , Animais , Antioxidantes/metabolismo , Aprendizagem da Esquiva , Estenose das Carótidas/tratamento farmacológico , Estenose das Carótidas/patologia , Estenose das Carótidas/psicologia , Doença Crônica , Demência Vascular/patologia , Demência Vascular/psicologia , Eletroencefalografia , Potenciação de Longa Duração , Masculino , Aprendizagem em Labirinto , Memória/efeitos dos fármacos , Atividade Motora , Plasticidade Neuronal/efeitos dos fármacos , Ratos , Ratos Sprague-DawleyRESUMO
Anxiety, hippocampus synaptic plasticity deficit, as well as pro-inflammatory cytokines, are involved in Alzheimer's disease (AD). The present study is designed to evaluate the possible therapeutic effect of crocin on anxiety-like behaviours, hippocampal synaptic plasticity and neuronal shape, as well as pro-inflammatory cytokines in the hippocampus using in vivo amyloid-beta (Aß) models of AD. The Aß peptide (1-42) was bilaterally injected into the frontal-cortex. Five hours after the surgery, the rats were given intraperitoneal (IP) crocin (30 mg/kg) daily up to 12 days. Elevated plus maze results showed that crocin treatment after bilateral Aß injection significantly increased the percentage of spent time into open arms, frequency of entries, and percentage of entries into open arms as compared with the Aß group. In the open field test, the Aß+crocin group showed a higher percentage of spent time in the centre and frequency of entries into central zone as compare with the Aß treated animals. Administering crocin increased the number of soma, dendrites and axonal arbores in the CA1 neurons among the rats with Aß neurotoxicity. Cresyl violet (CV) staining showed that crocin increased the number of CV-positive cells in the CA1 region of the hippocampus compared with the Aß group. Silver-nitrate staining indicated that crocin reduced neurofibrillary tangle formation induced by Aß. Crocin treatment attenuated the expression of TNF-α and IL-1ß mRNA in the hippocampus compared with the Aß group. Our results suggest that crocin attenuated Aß-induced anxiety-like behaviours and neuronal damage, and synaptic plasticity loss in hippocampal CA1 neurons may via its anti-inflammatory effects.
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Peptídeos beta-Amiloides , Carotenoides , Doença de Alzheimer , Animais , Hipocampo , Masculino , Transtornos da Memória , Neurônios , Fragmentos de Peptídeos , RatosRESUMO
OBJECTIVE: Coronavirus disease 2019 (COVID-19) is a world-wide pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, treatment of severe COVID-19 is far from clear. Therefore, it is urgent to develop an effective option for the treatment of patients with COVID-19. Most patients with severe COVID-19 exhibit markedly increased serum levels of pro-inflammatory cytokines, including interferon (IFN)-α, IFN-γ, and interleukin (IL)-1ß. Immunotherapeutic strategies have an important role in the suppression of cytokine storm and respiratory failure in patients with COVID-19. METHODS: A systematic search in the literature was performed in PubMed, Scopus, Embase, Cochrane Library, Web of Science, as well as Google Scholar preprint database using all available MeSH terms for Coronavirus, SARS-CoV-2, anti-rheumatoid agents, COVID-19, cytokine storm, immunotherapeutic drugs, IFN, interleukin, JAK/STAT inhibitors, MCP, MIP, TNF. RESULTS: Here, we first review common complications of COVID-19 patients, particularly neurological symptoms. We next explain host immune responses against COVID-19 particles. Finally, we summarize the existing experimental and clinical immunotherapeutic strategies, particularly anti-rheumatoid agents and also plasma (with a high level of gamma globulin) therapy for severe COVID-19 patients. We discuss both their therapeutic effects and side effects that should be taken into consideration for their clinical application. CONCLUSION: It is suggested that immunosuppressants, such as anti-rheumatoid drugs, could be considered as a potential approach for the treatment of cytokine storm in severe cases of COVID-19. One possible limitation of immunosuppressant therapy is their inhibitory effects on host anti-viral immune response. So, the appropriate timing of administration should be carefully considered.
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COVID-19/epidemiologia , COVID-19/terapia , Síndrome da Liberação de Citocina/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Animais , Antirreumáticos/uso terapêutico , COVID-19/imunologia , Citocinas/metabolismo , Inibidores Enzimáticos/uso terapêutico , Humanos , Imunização Passiva , Imunossupressores/uso terapêutico , Imunoterapia , Inflamação/tratamento farmacológico , Interferons/uso terapêutico , Interleucina-1/antagonistas & inibidores , Interleucina-6/antagonistas & inibidores , Janus Quinase 1/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Insuficiência Respiratória/terapia , Fator de Transcrição STAT1/antagonistas & inibidores , Transdução de Sinais , Soroterapia para COVID-19RESUMO
Abstract Norepinephrine in the basolateral amygdala (BLA) plays a pivotal role in mediating the effects of stress on memory functions in the hippocampus, however, the functional contribution of β1-adrenergic receptors on the BLA inputs to the CA1 region of hippocampus and memory function are not well understood. In the present study the role of β1-adrenoreceptor in the BLA on memory, neuronal arborization and long-term potentiation (LTP) in the CA1 region of hippocampus was examined by infusion the β1-adrenoreceptor agonist (Dobutamine; 0.5µl/side) or antagonist (Atenolol; 0.25µL/side) bilaterally into the BLA before foot-shock stress. Passive avoidance test results showed that Step-through latency time was significantly decreased in the stress group rats one, four and seven days after the stress, which intra-BLA injection of Atenolol or Dobutamine before stress couldn't attenuate this reduction. Barnes-maze results revealed that infusion of Dobutamine and Atenolol significantly reduced spatial memory indicators such as increased latency time, the number of errors and the distance traveling to achieve the target hole in the stress group. These learning impairments in stress rats correlated with a reduction of LTP in hippocampal CA1 synapses in-vivo, which infusion of Dobutamine and Atenolol couldn't attenuate the population spike amplitude and mean-field excitatory postsynaptic potentials (fEPSP) slope reduction induced by stress. Also, the Golgi-Cox staining demonstrated that infusion of Atenolol attenuated stress decreased CA1 region dendritic and axonal arborization. These results suggest that β1-adrenergic receptors activation or block seem to exacerbate stress-induced hippocampal memory deficits and this effect is independent of CA1 LTP modulation.
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Animais , Masculino , Ratos , Estresse Fisiológico/efeitos dos fármacos , Norepinefrina/metabolismo , Dobutamina/farmacologia , Região CA1 Hipocampal/efeitos dos fármacos , Agonistas de Receptores Adrenérgicos beta 1/farmacologia , Complexo Nuclear Basolateral da Amígdala/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Ratos Endogâmicos BB , Hipocampo/efeitos dos fármacosRESUMO
Abstract Crocus sativus L., Iridaceae, has been used worldwide in traditional medicinefor treatment ofsome neurological disorderssuch as depression. Post-traumatic stress disorder is a mental disorder developed in peoplewho experience stressful events. Since stress has been proposed tocause thehypothalamic-pituitary-adrenal axis malfunction in post-traumatic stress disorder patients, this study aimed at investigating the effect of saffron aqueous extract on hypothalamic-pituitary-adrenal axis activity in rats of post-traumatic stress disorder model. Here, Post-traumatic stress disorder animals received an acute electro foot shock; however, 5 min before the stress session, these animals received an intra-cerebral-ventricular (10 µg/rat) infusion of either saffron aqueous extract or saline. Twenty one days later, they were re-exposedto the stress box withoutinducing stress, andthen were examined for their freezing behavior. The impact of stress and saffron aqueous extract on serum corticosterone, corticotrophin releasing hormone gene expression in hypothalamus and glucocorticoid receptor gene expression in pituitary gland werethen evaluated on day 28. Intra-cerebral-ventricular injection of saffron aqueous extract resulted in an increase in serum corticosterone level and reduced symptoms of freezing behavior, and corticotrophin releasing hormone and glucocorticoid receptor gene expression in post-traumatic stress disorder groups.Saffron administration could improve the symptoms of stress-induced post-traumatic stress disorder, possiblythrough the adjustment ofhypothalamic-pituitary-adrenal axis function.
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OBJECTIVE: Post-traumatic stress disorder (PTSD) as one of the most devastating kinds of anxiety disorders, is the consequence of a traumatic event. Crocus sativus L., commonly known as saffron have been traditionally used for treatment of stress and anxiety. In this study, we evaluated the effects of peripheral administration of saffron, along with deep brain stimulation (DBS) in a post-traumatic stress disorder (PTSD) model caused by contextual fear conditioning (electrical foot shock chamber) in male Wistar rats. MATERIALS AND METHODS: rats (220-250 g) were divided into 7 groups (n=8) and underwent stereotactic surgery for implantation of the electrodes in the right-baso lateral of the amygdala (BLA). After 7 days, some animals received the foot shock, followed by another 7-day treatment (DBS treatment or combination treatment by saffron 5 mg/kg (i.p)) then freezing behavior as a predicted response in the absence of the foot shock (re-exposure time) and general anxiety were measured using elevated plus maze test. Serum corticosterone level and amygdala c-Fos protein expression were assessed using ELISA and Western blot analysis, respectively. RESULTS: DBS treatment and the combination therapy of saffron (5 mg/kg (I.P)) with DBS significantly (p<0.001) increased serum corticosterone levels. Also both treatments could significantly (p<0.001) reduce c-Fos protein expression and freezing behaviors time. However, DBS treatment had no effect on the general anxiety in rats with PTSD. On the other hand, combination therapy significantly (p<0.001) reduced anxiety behavior in rats with PTSD. CONCLUSION: These results might show the potential of this combination therapy for treatment of treatment-resistant PTSD patients.
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Parkinson's Disease (PD) is a frustrating condition characterized by motor and nonmotor deficits majorly caused by the loss of dopaminergic cells in the Substantia Nigra pars compacta (SNc) and destruction of the nigrostriatal pathway. Despite the very respectable advances in cutting-edge approaches for the treatment of PD, there exist numerous challenges that have incapacitated the definitive treatment of this disease. This review emphasized the development of various non-pharmaceutical therapeutic approaches and mainly highlighted the cutting-edge treatments for PD including gene- and stem cell-based therapies, targeted delivery of neurotrophic factors, and brain stimulation techniques such as Transcranial Magnetic Stimulation (TMS), transcranial Direct Current Stimulation (tDCS), and Deep Brain Stimulation (DBS). The review covered various gene therapy strategies including Adeno-Associated Virus-Glutamic Acid Decarboxylase (AAV-GAD), AAV-Aromatic L-Amino Acid Decarboxylase (AAV-AADC), Lenti-AADC/Tyrosine Hydroxylase/Guanosine Triphosphate- Cyclohydrolase I (Lenti-AADC/TH/GTP-CH1), AAV-Neurturin (AAV-NRTN), α-Synuclein silencing, and PRKN gene delivery. Also, the advantages, disadvantages, and the results of trials of these methods were discussed. Finally, reasons for the failure of PD treatment were described, with the hopes separated from hypes.
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Terapia Genética/métodos , Doença de Parkinson/terapia , Estimulação Transcraniana por Corrente Contínua/métodos , Animais , Humanos , Doença de Parkinson/genéticaRESUMO
INTRODUCTION: The present research aimed to examine Visual Working Memory (VWM) test scores, as well as hormonal, genomic, and brain anatomic changes in the male rhesus macaques exposed to Extremely Low Frequency Magnetic Field (ELF-MF). METHODS: Four monkeys were exposed to two different ELF-MF frequencies: 1 Hz (control) and 12 Hz (experiment) with 0.7 µT (magnitude) 4 h/d for 30 consecutive days. Before and after the exposure, VWM test was conducted using a coated devise on a movable stand. About 10 mL of the animals' blood was obtained from their femoral vain and used to evaluate their melatonin concentration. Blood lymphocytes were used for assaying the expressions of N-Methyl-D-aspartate NMDA-receptor genes expression before and after ELF exposure. Anatomical changes of hippocampus size were also assessed using MRI images. RESULTS: Results indicated that VWM scores in primates exposed to 12 Hz frequency ELF increased significantly. Plasma melatonin level was also increased in these animals. However, these variables did not change in the animals exposed to 1 Hz ELF. At last, expression of the NMDA receptors increased at exposure to 12 Hz frequency. However, hippocampal volume did not increase significantly in the animals exposed to both frequencies. CONCLUSION: In short, these results indicate that ELF (12 Hz) may have a beneficial value for memory enhancement (indicated by the increase in VWM scores). This may be due to an increase in plasma melatonin and or expression of NMDA glutamate receptors. However, direct involvement of the hippocampus in this process needs more research.
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OBJECTIVES: Post-traumatic stress disorder (PTSD), one of the most devastating kinds of anxiety disorders, is the consequence of a traumatic event followed by intense fear. In rats with contextual fear conditioning (CFC), a model of PTSD caused by CFC (electrical foot shock chamber), deep brain stimulation (DBS) alleviates CFC abnormalities. MATERIALS AND METHODS: Forty Male Wistar rats (220-250 g) were divided into 5 groups (n=8) and underwent stereotactic surgery to implant electrodes in the right basolateral nucleus of the amygdala (BLn). After 7 days, some animals received a foot shock, followed by another 7-day treatment schedule (DBS treatment). Next, freezing behavior was measured as a predicted response in the absence of the foot shock (re-exposure time). Blood serum corticosterone levels and amygdala c-Fos protein expression were assessed using Enzyme-linked immunosorbent assay (ELISA) and Western blot, respectively. Furthermore, freezing behaviors by re-exposure time test and general anxiety by elevated plus-maze (EPM) were evaluated. RESULTS: PTSD decreased serum corticosterone levels and increased both amygdala c-Fos expression and freezing behaviors. Therefore, DBS treatment significantly (P<0.001) enhanced serum corticosterone levels and could significantly (P<0.001) reduce both c-Fos protein expression and freezing behaviors' duration. However, DBS treatment has no effect on the general anxiety in PTSD rats. CONCLUSION: We argue that these outcomes might demonstrate the mechanism of DBS treatment, a complete therapeutic strategy, in PTSD patients.
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Extracellular beta-amyloid (Aß) accumulation and deposition is the main factor, which causes synaptic loss and eventually cells death in Alzheimer's disease (AD). Memory loss and long-term potentiation (LTP) dysfunction in the hippocampus are involved in the AD. The involvement of crocin, as the main and active constituent of saffron extract in learning and memory processes, has been proposed. Here we investigated the probable therapeutic effect of crocin on memory, LTP, and neuronal apoptosis using in vivo Aß models of the AD. The Aß peptide (1-42) was bilaterally administered into the frontal-cortex using stereotaxic apparatus. Five hours after surgery, rats were given intraperitoneal crocin (30 mg/kg) daily, which repeated for 12 days. Barnes maze results showed that administration of crocin significantly improves spatial memory indicators such as latency time to achieving the target hole and the number of errors when compared to Aß-group. Passive avoidance test revealed that crocin significantly increased the step-through-latency compared to Aß-treated alone. These learning deficits in Aß-treated animals correlated with a reduction of LTP in hippocampal CA1 synapses in freely moving rats, which crocin improved population spike amplitude and mean field excitatory postsynaptic potentials (fEPSP) slope reduction induced by Aß. Neuronal apoptosis was detected by TUNEL assay and the expression levels of c-Fos proteins were examined by Western blotting. Crocin significantly reduced the number of TUNEL-positive cells in the CA1 region and decreased c-Fos in the hippocampus compared to Aß-group. In vivo Aß treatment altered significantly the electrophysiological properties of CA1 neurons and crocin further confirmed a neuroprotective action against Aß toxicity.
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Antioxidantes/uso terapêutico , Região CA1 Hipocampal/patologia , Carotenoides/uso terapêutico , Potenciação de Longa Duração/efeitos dos fármacos , Transtornos da Memória , Neurônios/efeitos dos fármacos , Peptídeos beta-Amiloides/toxicidade , Animais , Aprendizagem da Esquiva/efeitos dos fármacos , Modelos Animais de Doenças , Estimulação Elétrica , Eletrodos Implantados , Marcação In Situ das Extremidades Cortadas , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/patologia , Fragmentos de Peptídeos/toxicidade , Proteínas Proto-Oncogênicas c-fos/metabolismo , Ratos , Ratos Wistar , Fatores de Tempo , VigíliaRESUMO
The rostral ventral tegmental area (VTAR) and central nucleus of amygdala (CeA) are considered the main regions for induction of psychological dependence on abused drugs, such as morphine. The main aim of this study was to investigate the transient inhibition of each right and left side as well as both sides of the VTAR and the CeA by lidocaine (2%) on morphine reward properties using the conditioned place preference (CPP) method. Male Wistar rats (250±20 g) 7 days after recovery from surgery and cannulation were conditioned to morphine (7.5 mg/kg) in CPP apparatus. Five minutes before morphine injection in conditioning phase, lidocaine was administered either uni- or bilaterally into the VTAR (0.25 µL/site) or CeA (0.5 µL/site). The results revealed that lidocaine administration into the left side, but not the right side of the VTAR and the CeA reduced morphine CPP significantly. The reduction was potentiated when lidocaine was injected into both sides of the VTAR and the CeA. The number of compartment crossings was reduced when lidocaine was injected into both sides of the VTAR and the CeA as well as the left side. Rearing was reduced when lidocaine was injected into the right, but not the left side of the VTAR. Sniffing and rearing increased when animals received lidocaine in the right side and reduced in the group that received lidocaine in the left side of the CeA. It was concluded that the right and the left side of VTAR and the CeA play different roles in morphine-induced activity and reward.
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Núcleo Central da Amígdala/efeitos dos fármacos , Condicionamento Operante/efeitos dos fármacos , Lateralidade Funcional , Morfina/farmacologia , Entorpecentes/farmacologia , Área Tegmentar Ventral/efeitos dos fármacos , Animais , Núcleo Central da Amígdala/fisiopatologia , Relação Dose-Resposta a Droga , Lidocaína/farmacologia , Masculino , Ratos Wistar , Recompensa , Área Tegmentar Ventral/fisiopatologiaRESUMO
ABSTRACT Stress can inhibit gonadal activity via Hypothalamus-Pituitary-Gonad (HPG) axis activity suppression. In the present study, effects of intermittent feeding (IF) on gonadal function under stress in male and female mice were evaluated. Twenty eight male and twenty eight female mice's were divided into four groups. The control group received adequate food and water without stress. The second group received four days of electric shock without food deprivation. The third group was deprived of food two hours/day for a week, and the fourth group was deprived of food (2 hours/day for seven consecutive days) and then electric foot shock stress was applied to them for four days. Blood samples were collected from all animals for plasma testosterone, estrogen and/or Interlukin-6 (IL-6) evaluation. The animals' gonads were also removed and fixed for the measure of their weight. Results showed that stress reduces both testosterone and estrogen levels, whereas IF did not change the hormone levels. In addition, stress increases blood IL-6 concentration. The combination of IF and stress, increased the hormone levels in animals. Stress and IF alone had no significant effect on gonadal weight in the male mice, whereas stress decreased gonadal weight in the females. Combination of stress with IF increased gonadal weight in both male and female mice. In conclusion stress showed a negative effect on gonadal function in both animals with more effect on females. Intermittent feeding inhibits the stress effect and even promotes the gonadal function in both sexes. The effect may be due to IL-6 reduction.
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Abstract Lavandula officinalis Chaix, Lamiaceae, extracts can inhibit inflammation and also pain induced by formalin in mice. This study evaluated the effects of L. officinalis hydro-alcoholic extract on pain induced by formalin and also cyclooxygenase (COX) type 1 and 2 activity in mice. To evaluate probable analgesic and anti-inflammatory effects of the extract, flowers were prepared by maceration and extraction in alcohol and their analgesic effects were studied in male mice, using formalin and hot plate tests. The effect of intraperitoneal hydro-alcoholic extracts of L. officinalis (100, 200, 250, 300, 400 and 800 mg/kg), subcutaneous morphine (10 mg/kg), dexamethasone (10 mg/kg; i.p.) and indomethacin (10 mg/kg; i.p.) on formalin induced pain were studied. Our results indicated that administration of the extract (100, 200, 250, 300, 400 and 800 mg/kg; i.p.) has inhibitory effects on inflammation induced by formalin injection into the animals hind paw. Moreover, this inhibitory effect was equal to the effects of morphine, dexamethasone and indomethacin. The extract in100, 200 and 300 mg/kg; significantly reduced heat-induced pain. The extract also reduced COX activity in dose dependent manner, where the inhibitory effect on COX1 activity was 33% and on COX2 activity was 45%. Here for the first time we show that L. officinialis extract can modulate pain and inflammation induced by formalin by inhibition of COX enzymes.
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BACKGROUND: Nicotine can activate dopaminergic neurons within the ventral tegmental area (VTA). However, there is no evidence about complete inhibition of VTA on nicotine reinforcement. METHODS: in the present study, we used conditioned-place preference (CPP) method to study the effect of transient inhibition of left and/or right side of the VTA by lidocaine on nicotine reward properties. Male Wistar rats seven days after recovery from surgery and cannulation were conditioned to nicotine (1.5 mg/kg) in an unbiased designed CPP apparatus. Five min before each nicotine injection in conditioning phase, lidocaine (2%) was administered either uni- or bi-laterally into the VTA (0.5µl/rat). RESULTS: results revealed that lidocaine administration into the left but not right side of the VTA reduced nicotine CPP significantly. The reduction was potentiated when lidocaine injected in to both sides of the VTA. In addition, the number of compartment crossing was reduced when lidocaine injected in both side of VTA as well as left side. On the other hand, rearing was reduced when lidocaine injected to the right but not left side of VTA. At last, sniffing was reduced only in the group in which received lidocaine in both side of VTA. Sniffing and rearing increased in the group in which received lidocaine in right side. CONCLUSION: It is concluded that the right and left side of VTA play different role in nicotine-induced activity and reward.