Expression Of Fibrillary Acidic Protein Research Articles

Effects of Electroacupuncture on the Expression of Glial Fibrillary Acidic Protein and Vascular Endothelial Growth Factor and Cell Structure in the Gliavascular Net of Cerebral Ischemic Tissues in Hypertensive Rats

Introduction: This study aims to explore the effects of electroacupuncture on the expression of GFAP and VEGF and cell structure in the glia vascular net of cerebral ischemic tissues in hypertensive rats. Material and Methods: Stroke-prone renovascular hypertensive rat (RHRSP) models and middle cerebral artery occlusion (MCAO) were established. After two hours of ischemia and at 1, 7, 14 and 28 days after reperfusion, the expression of GFAP and VEGF in rat cerebral ischemic tissues was detected by immunohistochemistry and light microscopy. Results: Positive GFAP cells were found in the semidarkness area after two hours of ischemic and one day of reperfusion in the control group, and these increased after 14 days, decreased after 14 days, and significantly decreased after 28 days, when compared to the sham group (P < 0.01). Compared to the control group, GFAP-positive cells significantly increased after 7, 14 and 28 days of ischemic and reperfusion in the electric acupuncture group. Then, this significantly increased and reached the maximum after seven days of reperfusion, but decreased after 14 days. Contrarily, this significantly decreased after 30 day, but remained higher than that in sham-operated group (P < 0.05). Compared to the control group, the number of positive VEGF cells increased after 7, 14 and 28 days of ischemic and reperfusion in the electric acupuncture group (P < 0.01). Conclusions: Electric acupuncture can promote neurofunctional recovery in the cerebral ischemic area. The mechanism may be correlated with the regulation of the expression of GFAP and VEGF, and the rebuilding of the gliavascular net of cerebral ischemic tissues, thereby decreasing cerebral ischemic damage.

Poly-guanidine shows high cytotoxicity in glioma cell cultures and glioma stem cells

Glioblastoma multiforme (GBM) is a malignant CNS tumor with a poor prognosis. GBM shows aberrant glycosylation with hypersialylation. This property is a potential target for therapy. This study investigates the growth inhibitory efficacy of poly-guanidine (GuaDex), with an affinity for sialic acid (Sia). Glioma cell cultures and patient-derived glioma cell lines (PDGCLs) expressing Prominin-1 (CD133) were used. Human fibroblasts and astrocyte-derived cells were used as controls. Temozolomide (standard GBM drug, TMZ) and DMSO were used as a comparison. GuaDex at 1–10 µM concentrations, were incubated for 3.5–72 h and with PDGCLs cells for 6–24 h. The cytotoxicity was estimated with a fluorometric cytotoxicity assay (FMCA). Fluorescence-labelled GuaDex was used to study the cell interactions. Sia expression was confirmed with a fluorescence labelled Sia binding lectin. Expression of glial fibrillary acidic protein was determined. GuaDex induction of growth inhibition was fast, showing after less than 5 min incubation while the control cells were not affected even after 50 min incubation. The growth inhibitory effect on PDGCLs spheroids was persistent still showing after 4 weeks post-treatment. The growth inhibition of GuaDex was induced at low µM concentrations while TMZ induced only a slight inhibition at mM concentrations. GuaDex efficacy appears significant and warrants further studies.

The Role of 5-HT1A Receptors and Neuronal Nitric Oxide Synthase in a Seizur Induced Kindling Model in Rats.

Dentate gyrus (DG) has a high density of 5-HT1A receptors. It has neural nitric oxide synthase (nNOS), which is involved in neural excitability. The purpose of this study was to investigate the role of 5-HT1A receptors and nNOS of DG in perforant path kindling model of epilepsy. To achieve this purpose, a receptor antagonist (WAY100635, 0.1mg/kg, intracerebroventricular, i.c.v) and neuronal nitric oxide synthase inhibitor (7-NI, 15mg/kg, intraperitoneal, i.p.) were injected during kindling aquisition. Adult male Wistar rats (280 ± 20g) were used in this study Animals were kindled through the daily administration of brief electrical stimulations (10 stimulations per day) to the perforant pathway. Field potential recordings were performed for 20min in DG beforehand. Additionally, glial fibrillary acidic protein (GFAP) expression rate in the DG was determined using immunohistochemistry as a highly specific marker for glia. WAY100635 (0.1mg/kg) significantly attenuated the kindling threshold compared to the kindled + vehicle group (P < 0.001). The co-administration of WAY100635 with 7-NI, exerted a significant anticonvulsive effect. Furthermore, the slope of field Excitatory Post Synaptic Potentials (fEPSP) at the end of 10days in the kindled + 7-NI + WAY100635 group was significantly lower than in the kindled + vehicle group (P < 0.001). Furthermore, immunohistochemistry showed that the density of GAFP+ cells in the kindled + 7-NI + WAY100635 group was significantly higher than in the kindled + vehicle group (P < 0.001). Our data demonstrate that antagonists of 5-HT1A receptors have proconvulsive effects and that astrocyte cells are involved in this process, while nNOS has aninhibitory effect on neuronal excitability.

Traumatic brain injury in the presence of A\u03b2 pathology affects neuronal survival, glial activation and autophagy

Traumatic brain injury (TBI) presents a widespread health problem in the elderly population. In addition to the acute injury, epidemiological studies have observed an increased probability and earlier onset of dementias in the elderly following TBI. However, the underlying mechanisms of the connection between TBI and Alzheimer’s disease in the aged brain and potential exacerbating factors is still evolving. The aim of this study was to investigate cellular injury-induced processes in the presence of amyloid β (Aβ) pathology. For this purpose, a co-culture system of cortical stem-cell derived astrocytes, neurons and oligodendrocytes were exposed to Aβ42 protofibrils prior to a mechanically induced scratch injury. Cellular responses, including neurodegeneration, glial activation and autophagy was assessed by immunoblotting, immunocytochemistry, ELISA and transmission electron microscopy. Our results demonstrate that the combined burden of Aβ exposure and experimental TBI causes a decline in the number of neurons, the differential expression of the key astrocytic markers glial fibrillary acidic protein and S100 calcium-binding protein beta, mitochondrial alterations and prevents the upregulation of autophagy. Our study provides valuable information about the impact of TBI sustained in the presence of Aβ deposits and helps to advance the understanding of geriatric TBI on the cellular level.

Retinal Astrocytes and Microglia Activation in Diabetic Retinopathy Rhesus Monkey Models

ABSTRACT Purpose To assess the retinal neurodegeneration in type-1 diabetes mellitus (T1DM) and type-2 diabetes mellitus (T2DM) rhesus monkeys, and to investigate whether alterations of glial cells occur in the early stage of diabetic retinopathy (DR). Materials and methods T1DM rhesus monkeys were established by daily intravenous injections of streptozotocin (STZ, 25 mg/kg body weight) in citrate buffer (pH 4.5) for 5 days, while T2DM rhesus monkeys were induced by feeding with high-fat diet. The period of DR in rhesus monkeys was evaluated by fundoscopy and optical coherence tomography (OCT). Afterward, the morphological changes of inner neurons and glial cells in the retina were detected by immunofluorescence (IF). Results When compared with the control groups, no difference was observed in both T1DM and T2DM by fundus photographs, while slight exudation and effusion in the blood vessels of retina of rhesus monkeys were found by OCT in DM rhesus monkeys. In addition, the expression of glial fibrillary acidic protein (GFAP) and ionized calcium-binding adaptor molecule (Iba1) were significantly increased in both T1DM (P < .01) and T2DM (P < .05) rhesus monkeys. Moreover, the positive expression of PKC-α, parvalbumin, and NeuN were significantly decreased, while the positive expression of calbindin showed no difference in T1DM group. However, only the expression cells of PKC-α were reduced in T2DM group when compared with that of the control group. Conclusion Astrocytes activation, reactive gliosis, and neurodegeneration were observed in both T1DM and T2DM rhesus monkey models at the early stage of DR.

Music Therapy Alleviates Motor Dysfunction in Rats With Focal Cerebral Ischemia-Reperfusion Injury by Regulating BDNF Expression.

Background/Aim: Music-based therapy plays a role in central nervous system diseases. We aimed to explore the effect of different doses and durations of music therapy on motor function recovery after stroke and the underlying molecular mechanisms.Methods: Adult male Sprague–Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 1 h, which was followed by reperfusion. In experiment 1, the rats that survived 1 week after MCAO surgery were randomly allocated into four groups (n = 10 per group): MCAO group, 1 h music group (Mozart K.448 music therapy 1 h per day for 2 weeks), 12 h music group (Mozart K.448 music therapy 12 h/day for 2 weeks), and accelerated music group (reversely accelerated music therapy 12 h for 2 weeks, AM group). In experiment 2, the survived rats were randomly divied into three groups: MCAO group, 12 h music group (music therapy 12 h/day for 3 weeks), and 12 h music-R group (music therapy 12 h/day for 2 weeks and rest for 1 week). Three neuroscores were evaluated daily, starting on the first day after surgery until the end of the experiment. The rats were killed 3 weeks after MCAO surgery in experiment 1 or 4 weeks after surgery in experiment 2. Nissl staining of infart core, peri-infarct zone, and motor cortex was performed to assess neuronal survival and regeneration. Western blot and immunofluorescence were used to detect the expression and distribution of brain-derived neurotrophic factor (BDNF) and glial fibrillary acidic protein (GFAP) in ipsilateral hemispheres.Results: In the experiment of different music therapy doses, the motor function in the 12-h music group but not in the 1-h music group and AM group was significantly improved compared with that of the MCAO group. The BDNF protein level of the ipsilateral hemisphere motor cortex in the 12-h music group and the 1-h music group was higher than that of the MCAO group. The neurons and Nissl bodies were more in the 12-h music group than in the MCAO group. Immunofluorescence assay showed that a 12 h music therapy induces BDNF and GFAP accumulation at the damage boundary. In the experiment of different music therapy durations, 3 weeks music therapy (12 h music group) induced more longer cell synapses and more clearer cell-to-cell connections than 2 weeks music intervention (12 h music-R group). Moreover, the GFAP morphology in the 12-h music group was more similar to mature activated astrocytes than that in the 12-h music-R group.Conclusions: Music therapy may improve poststroke motor function and promote neuronal repair in the long term. The mechanism may be through stimulating BDNF and GFAP secretion in the injured motor cortex.

Photoactivation of TGF\u03b2/SMAD signaling pathway ameliorates adult hippocampal neurogenesis in Alzheimer\u2019s disease model

BackgroundAdult hippocampal neurogenesis (AHN) is restricted under the pathological conditions of neurodegenerative diseases, especially in Alzheimer’s disease (AD). The drop of AHN reduces neural circuit plasticity, resulting in the decrease of the generation of newborn neurons in dentate gyrus (DG), which makes it difficult to recover from learning/memory dysfunction in AD, therefore, it is imperative to find a therapeutic strategy to promote neurogenesis and clarify its underlying mechanism involved.MethodsAmyloid precursor protein/presenilin 1 (APP/PS1) mice were treated with photobiomodulation therapy (PBMT) for 0.1 mW/mm2 per day in the dark for 1 month (10 min for each day). The neural stem cells (NSCs) were isolated from hippocampus of APP/PS1 transgenic mice at E14, and the cells were treated with PBMT for 0.667 mW/mm2 in the dark (5 min for each time).ResultsIn this study, photobiomodulation therapy (PBMT) is found to promote AHN in APP/PS1 mice. The latent transforming growth factor-β1 (LTGFβ1) was activated in vitro and in vivo during PBMT-induced AHN, which promoted the differentiation of hippocampal APP/PS1 NSCs into newborn neurons. In particular, behavioral experiments showed that PBMT enhanced the spatial learning/memory ability of APP/PS1 mice. Mechanistically, PBMT-stimulated reactive oxygen species (ROS) activates TGFβ/Smad signaling pathway to increase the interaction of the transcription factors Smad2/3 with Smad4 and competitively reduce the association of Smad1/5/9 with Smad4, thereby significantly upregulating the expression of doublecortin (Dcx)/neuronal class-III β-tubulin (Tuj1) and downregulating the expression of glial fibrillary acidic protein (GFAP). These in vitro effects were abrogated when eliminating ROS. Furthermore, specific inhibition of TGFβ receptor I (TGFβR I) attenuates the DNA-binding efficiency of Smad2/3 to the Dcx promotor triggered by PBMT.ConclusionOur study demonstrates that PBMT, as a viable therapeutic strategy, directs the adult hippocampal APP/PS1 NSCs differentiate towards neurons, which has great potential value for ameliorating the drop of AHN in Alzheimer’s disease mice.

Maternal stress programs a demasculinization of glutamatergic transmission in stress-related brain regions of aged rats

Brain aging may be programmed by early-life stress. Aging affects males and females differently, but how perinatal stress (PRS) affects brain aging between sexes is unknown. We showed behavioral and neurobiological sex differences in non-stressed control rats that were strongly reduced or inverted in PRS rats. In particular, PRS decreased risk-taking behavior, spatial memory, exploratory behavior, and fine motor behavior in male aged rats. In contrast, female aged PRS rats displayed only increased risk-taking behavior and reduced exploratory behavior. PRS induced large reductions in the expression of glutamate receptors in the ventral and dorsal hippocampus and prefrontal cortex only in male rats. PRS also reduced the expression of synaptic vesicle-associated proteins, glucocorticoid receptors (GR), and mineralocorticoid receptors (MR) in the ventral hippocampus of aged male rats. In contrast, in female aged rats, PRS enhanced the expression of MRs and brain-derived neurotrophic factor (BDNF) in the ventral hippocampus and the expression of glial fibrillary acidic protein (GFAP) and BDNF in the prefrontal cortex. A common PRS effect in both sexes was a reduction in exploratory behavior and metabotropic glutamate (mGlu2/3) receptors in the ventral hippocampus and prefrontal cortex. A multidimensional analysis revealed that PRS induced a demasculinization profile in glutamate-related proteins in the ventral and dorsal hippocampus and prefrontal cortex, as well as a demasculinization profile of stress markers only in the dorsal hippocampus. In contrast, defeminization was observed only in the ventral hippocampus. Measurements of testosterone and 17-β-estradiol in the plasma and aromatase in the dorsal hippocampus were consistent with a demasculinizing action of PRS. These findings confirm that the brains of males and females differentially respond to PRS and aging suggesting that females might be more protected against early stress and age-related inflammation and neurodegeneration. Taken together, these results may contribute to understanding how early environmental factors shape vulnerability to brain aging in both sexes and may lay the groundwork for future studies aimed at identifying new treatment strategies to improve the quality of life of older individuals, which is of particular interest given that there is a high growth of aging in populations around the world.

The Effect of Induced Diabetes Mellitus on the Cerebellar Cortex of Adult Male Rat and the Possible Protective Role of Oxymatrine: A Histological, Immunohistochemical and Biochemical Study

ABSTRACT Diabetes mellitus (DM) represents a widespread metabolic disease with a well-known neurotoxicity in both central and peripheral nervous systems. Oxymatrine is a traditional Chinese herbal medicine that has various pharmacological activities including: anti-oxidant, anti-apoptotic and anti-inflammatory potentials. The present work aimed to study the impact of diabetes mellitus on the cerebellar cortex of adult male albino rat and to evaluate the potential protective role of oxymatrine. Fifty-five adult male rats were randomly divided into three groups: group I served as control, group II was given oxymatrine (80 mg/kg/day) orally for 8 weeks and group III was given a single dose of streptozotocin (50 mg/kg) intaperitoneally to induce diabetes. Then diabetic rats were subdivided into two subgroups: subgroup IIIa that received no additional treatment and subgroup IIIb that received oxymatrine similar to group II. The diabetic group revealed numerous changes in the Purkinje cell layer in the form of multilayer arrangement of Purkinje cells, shrunken cells with deeply stained nuclei as well as focal loss of the Purkinje cells. A significant increment in glial fibrillary acidic protein (GFAP) and synaptophysin expression were reported in immunohistochemistry compared with the control group. Transmission electron microscopy showed irregularity and splitting of myelin sheaths in the molecular layer, dark shrunken Purkinje cells with ill-defined nuclei, dilated Golgi saccules and dense granule cells with irregular nuclear outlines in the granular layer. In contrast, these changes were less evident in diabetic rats that received oxymatrine. In conclusion, Oxymatrine could protect the cerebellar cortex against changes induced by DM.

Progressive Loss of Retinal Ganglion Cells in Activating Protein-2β Neural Crest Cell Knockout Mice

ABSTRACT Purpose: Our lab has shown that conditionally disrupting the transcription factor activating protein 2β (Tfap2b) gene, responsible for the activating protein-2β (AP-2β) transcription factor, exclusively in cranial neural crest cells (AP-2β NCC KO), leads to anterior segment dysgenesis and a closed angle phenotype. The purpose of the current study is to determine if there is a progressive loss of retinal ganglion cells (RGCs) in the mutant over time and whether this loss was associated with macroglial activity changes and elevated intraocular pressure (IOP). Methods: Using the Cre-loxP system, we generated a conditional knockout of Tfap2b exclusively in cranial NCC (AP-2β NCC KO). Immunohistochemistry was performed using anti-Brn3a, anti-GFAP and anti-Vimentin antibodies. IOP was measured using a tonometer and the data was analyzed using GraphPad Prism software. Brn3a and DAPI positive cells were counted using Image-J and statistical analysis was performed with GraphPad Prism software. Results: Our findings revealed that while no statistical difference in Brn3a expression was observed between wild-type and mutant mice at postnatal day (P) 4 or P10, at P40 (p < .01) and P42 (p < .0001) Brn3a expression was significantly reduced in the mutant retina at the region of the ONH. There was also increased expression of glial fibrillary acidic protein (GFAP) by Müller cells in the AP-2β NCC KO mice at P35 and P40, indicating the presence of neuroinflammation. Moreover, increased IOP was observed starting at P35 and continuing at P40 and P42 (p < .0001 for all three ages examined). Conclusions: Together, these findings suggest that the retinal damage observed in the KO mouse becomes apparent by P40 after increased IOP was observed at P35 and progressed over time. The AP-2β NCC KO mouse may therefore be a novel experimental model for glaucoma.

ANTIDEPRESSANT-LIKE EFFECT OF DIMETHYL FUMARATE AND ASTROCYTE CHANGES IN HIPPOCAMPUS OF MICE SUBMMITED TO MODEL OF DEPRESSION

Introduction: Depression is a psychiatric condition of high prevalence worldwide and is associated with inflammation. Dimethyl fumarate, used to treat psoriasis and multiple sclerosis, has demonstrated an anti-inflammatory effect. Objective: To evaluate the effect of dimethyl fumarate on depression, through the immobility time in the forced swim test, and on astrocyte proliferation, through the expression of glial fibrillary acidic protein in the hippocampus of mice submitted to Chronic Unpredictable Mild Stress- induced model of depression. Methods: Male mice were divided into three groups: control(1), stressed(2), stressed+dimethyl fumarate (3). Groups 2 and 3 were subjected to 28 days of exposure to unpredictably applied stressors. From the 14th day, group 3 was treated with dimethyl fumarate (oral). At the end, the hippocampus was removed to determination of glial fibrillary acidic protein expression by immunofluorescence. Results: The immobility time was increased by chronic stress compared to the control and the treatment with dimethyl fumarate decreased this parameter, compared to the stressed group [F (9, 92) = 6,460; 1vs2: p &lt;0.01, 2vs3: p &lt;0.001]. Glial fibrillary acidic protein expression was reduced by chronic stress compared to control in the two areas of the hippocampus analyzed and treatment with dimethyl fumarate did not interfere in this parameter [CA1: F (2, 6) = 5.173, 1vs2: p &lt;0.05; Dentate gyrus: F (2, 7) = 31.44, 1vs2: p &lt;0.001]. Conclusion: Dimethyl fumarate has antidepressant-like effect in mice, however more studies need to be carried out to elucidate the neuroinflammatory mechanism of this drug.

Aragonite-Polylysine: Neuro-Regenerative Scaffolds with Diverse Effects on Astrogliosis.

Biomaterials, especially when coated with adhesive polymers, are a key tool for restorative medicine, being biocompatible and supportive for cell adherence, growth, and function. Aragonite skeletons of corals are biomaterials that support survival and growth of a range of cell types, including neurons and glia. However, it is not known if this scaffold affects neural cell migration or elongation of neuronal and astrocytic processes, prerequisites for initiating repair of damage in the nervous system. To address this, hippocampal cells were aggregated into neurospheres and cultivated on aragonite skeleton of the coral Trachyphyllia geoffroyi (Coral Skeleton (CS)), on naturally occurring aragonite (Geological Aragonite (GA)), and on glass, all pre-coated with the oligomer poly-D-lysine (PDL). The two aragonite matrices promoted equally strong cell migration (4.8 and 4.3-fold above glass-PDL, respectively) and axonal sprouting (1.96 and 1.95-fold above glass-PDL, respectively). However, CS-PDL had a stronger effect than GA-PDL on the promotion of astrocytic processes elongation (1.7 vs. 1.2-fold above glass-PDL, respectively) and expression of the glial fibrillary acidic protein (3.8 vs. and 1.8-fold above glass-PDL, respectively). These differences are likely to emerge from a reaction of astrocytes to the degree of roughness of the surface of the scaffold, which is higher on CS than on GA. Hence, CS-PDL and GA-PDL are scaffolds of strong capacity to derive neural cell movements and growth required for regeneration, while controlling the extent of astrocytic involvement. As such, implants of PDL-aragonites have significant potential as tools for damage repair and the reduction of scar formation in the brain following trauma or disease.

The role of extracellular vesicles in the diagnosis of glioblastoma progression

The article reviews studies highlighting the role of extracellular molecules in non-invasive diagnosis of glioblastoma recurrence. Glioblastoma is the most common malignant tumor of the brain characterized by fatal outcome prognosis. Current treatment of tumor recurrence allows to increase patient survival, improve functional outcome and decrease caregivers» load. The standard method of recurrence diagnosis is neuroimaging which at early stages cannot distinguish between tumor recurrence and post-radiation changes. Currently in oncology, liquid biopsy and marker detection in circulating extracellular vesicles are considered promising approaches allowing to obtain early and differential tumor diagnosis, determine dynamic molecular and genetic status of the tumor, diagnose tumor recurrence at early stages. In this context, the most promising approach to glioblastoma diagnosis is associated with studying of expression of glial fibrillary acidic protein (GFAP), epidermal growth factor receptor (EGFR), its mutant variant EGFRvIII, podoplanin (PDPN) and isocitrate dehydrogenase 1 (IDH1) in extracellular vesicles; for primary glioblastoma diagnosis and early recurrence: studying of microRNA-210, -301a, -222, -123-3p, -21; for control of immunotherapy effectiveness in patients with recurrent forms of glioblastoma after standard treatment: evaluation of СD9+ / GFAP+ / survivin+ exosomes in plasma.

Differentiation of Tumorigenic C6 Glioma Cells Induced by Enhanced IL-6 Signaling.

Background and objectives: Cancer stem cells (CSCs) are obstacles to cancer therapy due to their therapeutic resistance, ability to initiate neoplasia, and roles in tumor relapse and metastasis. Efforts have been made to cure CSCs, such as the use of differentiation therapy, which induces cancer stem-like cells to undergo differentiation and decrease their tumorigenicity. Interleukin 6 (IL-6) upregulates the expression of glial fibrillary acidic protein (GFAP) in C6 glioma cells, indicating that it is able to induce the differentiation of these cells. The C6 glioma cell line forms a high percentage of cancer stem-like cells, leading us to speculate whether IL-6 signaling could modulate the differentiation of tumorigenic C6 glioma cells. However, we observed that IL-6 alone could not efficiently induce the differentiation of these cells. Therefore, different IL-6 signaling elicitors, including IL-6 alone, a combination of IL-6 and soluble IL-6 receptor (IL-6/sIL-6R), and tumor necrosis factor-α (TNF-α) plus IL-6/sIL-6R (TNF-α/IL-6/sIL-6R), were evaluated for their potential use in differentiation therapy. Materials and Methods: The potential of IL-6 signaling elicitors in differentiation therapy were examined by assessing changes in biomarker levels, the rate of cell proliferation, and tumorigenicity, respectively. Results: Enhanced IL-6 signaling could effectively induce C6 glioma cell differentiation, as determined by observed variations in the expression of differentiation, cell cycle, and stem cell biomarkers. Additionally, the total cell population and the tumorigenicity of glioma cells were all considerably reduced after TNF-α/IL-6/sIL-6R treatment. Conclusions: Our findings provide evidence that enhanced IL-6 signaling can efficiently promote tumorigenic C6 glioma cells to undergo differentiation.

Expression of Nestin and Glial Fibrillary Acidic Protein in the Marginal Ischemic Zone of the Brain in SHR Rats.

We studied spatial organization and structural characteristics of striatal glial cells in spontaneously hypertensive rats (SHR) in 48 h after 30-min focal ischemia. Immunocytochemical analysis of nestin and glial fibrillar acidic protein (GFAP) revealed 3 types of activated astrocytes: expressing only nestin, only GFAP, or both markers. There were no nestin-immunopositive astrocytes in the striatum of sham-operated rats. In cells expressing nestin and GFAP, localization of these markers did not completely coincide, which can be explained by different functions of these proteins or formation of heterodimers of nestin with other intermediate filament proteins.

Methimazole Inhibits the Expression of GFAP and the Migration of Astrocyte in Scratched Wound Model In Vitro.

Astrocytes respond to central nervous system (CNS) insults with varieties of changes, such as cellular hypertrophy, migration, proliferation, scar formation, and upregulation of glial fibrillary acidic protein (GFAP) expression. While scar formation plays a very important role in wound healing and prevents further bleeding by forming a physical barrier, it is also one of key features of CNS injury, resulting in glial scar formation (astrogliosis), which is closely related to treatment resistant epilepsy, chronic pain, and other devastating diseases. Therefore, slowing the astrocytic activation process may give a time window of axonal growth after the CNS injury. However, the underlying mechanism of astrocytic activation remains unclear, and there is no effective therapeutic strategy to attenuate the activation process. Here, we found that methimazole could effectively inhibit the GFAP expression in physiological and pathological conditions. Moreover, we scratched primary cultures of cerebral cortical astrocytes with and without methimazole pretreatment and investigated whether methimazole could slow the healing process in these cultures. We found that methimazole could inhibit the GFAP protein expression in scratched astrocytes and prolong the latency of wound healing in cultures. We also measured the phosphorylation of extracellular signal-regulated kinase (ERK) in these cultures and found that methimazole could significantly inhibit the scratch-induced GFAP upregulation. For the first time, our study demonstrated that methimazole might be a possible compound that could inhibit the astrocytic activation following CNS injury by reducing the ERK phosphorylation in astrocytes.

Histological study on the effect of single prolonged stress model on the hippocampus of adult male albino rat

Abstract Introduction: Post- traumatic stress disorder (PTSD) is a psychiatric disorder which occurs after the experience of life threatening events as natural disasters, military combat, serious accidents, or violent sexual assaults. It has a severe impact on quality of life. Aim of the work to study the effect of single prolonged stress on the structure of hippocampus in adult male albino rats. Materials and Methods 20 adult male albino rats were randomly divided into four groups control group (group I) and single prolonged stress group examined at day 1(group II), day 7 (group III) and day 14 (groupIV). Rats were restrained by placing them in plastic restrainers, immediately followed by 20 minutes of forced swimming in 20–24°C water. Rats were exposed to ether until general anesthesia then they were placed in their home cages. At the end of the experiment, the hippocampi were taken and processed for light microscopic study. Results pyramidal cells of the CA3 region of the hippocampus showed progressive degeneration with passage of time from day 1 to day 14 with decrease in thickness. Transient increase in glial fibrillary acidic protein (GFAP) expression in the astrocytes of the hippocampus was detected at day 1 followed by reduction in GFAP expression started at day seven and continued to day 14. Conclusion post-traumatic stress PTSD causes significant structural hippocampal neuronal damage affecting the CA3 hippocampal subfield.

Diallyl sulfide alleviates cyclophosphamide-induced nephropathic encephalopathy in rats

Diallyl sulfide (DAS) is a garlic-derived organosulfur compound. The current study was planned to evaluate the protecting effects of DAS against cyclophosphamide (CP)-induced nephropathic encephalopathy. DAS (100 mg/kg) was orally administered for 4 days, 60 min after the last dose, rats were injected with CP (150 mg/kg). DAS treatment before CP significantly decreased serum urea, creatinine, sodium, potassium, calcium, blood urea nitrogen (BUN), C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-1β (IL-1ß) and tumor necrosis factor-alpha (TNF-α) compared with CP-treated rats. DAS treatment decreased malondialdehyde (MDA) and increased superoxide dismutase (SOD) and reduced glutathione (GSH) levels in the renal tissues and significantly attenuated the elevated neurotransmitters N-methyl-D-aspartate/adenosine triphosphate (NMDA), γ-aminobutyric acid (GABA) levels and remarkably restored neuronal nitric oxide (NO) level and nitric oxide synthase (nNOS) activity in the brain compared to CP-treated rats. DAS for 4 consecutive days before CP showed moderate positive immunohistochemically expression of the glial fibrillary acidic protein (GFAP) in the brain and kidney tissues comparable to CP-treated rats. DAS afforded renal and neuroprotection against CP-induced nephropathic encephalopathy due to its capacity to ameliorates the afore-mentioned biochemical parameters which were supported by histopathological and immunohistochemically examination.

Dexmedetomidine ameliorates memory impairment in sleep-deprived mice

ABSTRACT The selective α2-adrenergic receptor agonist dexmedetomidine acts as an analgesic, sedative, and anesthetic adjuvant. The most common consequence of sleep deprivation is memory impairment. We investigated whether dexmedetomidine can counteract memory impairment caused by sleep deprivation and suppress the production of inflammatory factors. For inducing sleep deprivation, adult male mice were placed inside a water cage containing 15 platforms immersed in water up to 1 cm for 7 days. One day after sleep deprivation, dexmedetomidine at the respective dosage (5, 10, and 20 μg/kg) and α2-adrenoceptor antagonist atipamezole (250 μg/kg) were intraperitoneally injected into the mice, once per day for six days. The step-down avoidance task and the Morris water maze test were performed. Western blot analysis was performed to determine the levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-6, brain-derived neurotrophic factor (BDNF), tyrosine kinase B (TrkB), nuclear transcription factor-κB (NF-κB), inhibitor of κBα (IκBα), and ionized calcium binding adapter molecule I (Iba-1) in the hippocampus. Immunohistochemistry was performed for the determination of Ki-67 and glial fibrillary acidic protein (GFAP) expression in the hippocampal dentate gyrus. Dexmedetomidine ameliorated sleep deprivation-induced deterioration of short-term memory and spatial learning ability. Dexmedetomidine inhibited production of inflammatory mediators caused by sleep deprivation. Dexmedetomidine also prevented the decrease in BDNF, TrkB expression, and cell proliferation induced by sleep deprivation. Dexmedetomidine could be used to counteract the neuropathological effects of sleep deprivation.

The effects of early treadmill training combined with ultrashort wave irradiation on functional recovery from spinal cord injury

Objective To investigate the effect of early-stage training combined with the ultrashort wave therapy on the functional recovery of rats after a spinal cord injury, and to observe the expression of aquaporin protein-4 (AQP-4) and glial fibrillary acidic protein (GFAP). Methods Fifty female Sprague-Dawley rats had spinal cord injury (SCI) induced using the modified Allen′s method. After successful modeling, 40 were randomly divided into a sham operation group, a control group, an ultrashort wave group, a treadmill group and a combined group, each of 8. Motor function in their hind limbs was evaluated 4 weeks after the operation using BBB scoring. GFAP and AQP-4 immunohistochemical staining were used to determine the integral optical density (IOD) of the protein expression. Results The average BBB score of the sham operation group was 21, while the other four groups averages were all less than 1 on the 1st day after the operation. They gradually increased with time, and by 4 weeks the increases were significant. Compared with the control group at the same time point, the average BBB scores of the treadmill and the combined groups were significantly higher. Compared with the ultrashort wave group, the average BBB score of the treadmill group was higher after 4 weeks, and the combined group′s average was significantly higher at 2, 3 and 4 weeks after the operation. Four weeks after the SCI modeling, the average AQP-4 IOD and GFAP IOD levels of the ultrashort wave group, the treadmill group and the combined group were lower than that of the control group, while the average AQP-4 and GFAP IOD levels of the combined group were significantly lower than those of the ultrashort wave group. Compared with the treadmill group, the combined group had a significantly lower average GFAP level. Conclusions Both treadmill training and ultrashort wave treatment promote motor function recovery after a spinal cord injury. The mechanism may be related to downregulation of AQP-4 and GFAP expression at the injured site. Combining the two treatments gives better effects. Key words: Spinal cord injury; Treadmill training; Ultrashort wave irradiation; Auaporin protein-4; Glial fibrillary acidic protein