Alexander Disease Modeling in Zebrafish: An In Vivo System Suitable to Perform Drug Screening.

Alexander disease (AxD) is a rare astrogliopathy caused by heterozygous mutations, either inherited or arising de novo, on the glial fibrillary acid protein (GFAP) gene (17q21). Mutations in the GFAP gene make the protein prone to forming aggregates which, together with heat-shock protein 27 (HSP27), αB-crystallin, ubiquitin, and proteasome, contribute to form Rosenthal fibers causing a toxic effect on the cell. Unfortunately, no pharmacological treatment is available yet, except for symptom reduction therapies, and patients undergo a progressive worsening of the disease. The aim of this study was the production of a zebrafish model for AxD, to have a system suitable for drug screening more complex than cell cultures. To this aim, embryos expressing the human GFAP gene carrying the most severe p.R239C under the control of the zebrafish gfap gene promoter underwent functional validation to assess several features already observed in in vitro and other in vivo models of AxD, such as the localization of mutant GFAP inclusions, the ultrastructural analysis of cells expressing mutant GFAP, the effects of treatments with ceftriaxone, and the heat shock response. Our results confirm that zebrafish is a suitable model both to study the molecular pathogenesis of GFAP mutations and to perform pharmacological screenings, likely useful for the search of therapies for AxD.

Rutin and Selenium Co-administration Reverse 3-Nitropropionic Acid-Induced Neurochemical and Molecular Impairments in a Mouse Model of Huntington's Disease.

Systemic administration of 3-nitropropionic acid (3-NPA) is commonly used to induce Huntington's disease (HD)-like symptoms in experimental animals. Here, the potential neuroprotective efficiency of rutin and selenium (RSe) co-administration on 3-NPA-induced HD-like symptoms model in mice was investigated. 3-NPA injection evoked severe alterations in redox status, as indicated via increased striatal malondialdehyde and nitric oxide levels, accompanied by a decrease in levels of antioxidant molecules including glutathione, glutathione peroxidase, glutathione reductase, superoxide dismutase, and catalase. Moreover, 3-NPA potentiated inflammatory status by enhancing the production of interleukin-1ß, tumor necrosis factor-α, and myeloperoxidase activity. Pro-apoptotic cascade was also recorded in the striatum as evidenced through upregulation of cleaved caspase-3 and Bax, and downregulation of Bcl-2. 3-NPA activated astrocytes as indicated by the upregulated glial fibrillary acidic protein and inhibited brain-derived neurotrophic factor. Furthermore, perturbations in cholinergic and monoaminergic systems were observed. RSe provided neuroprotective effects by preventing body weight loss, oxidative stress, neuroinflammation, and the apoptotic cascade. RSe inhibited the activation of astrocytes, increased brain-derived neurotrophic factor, and improved cholinergic and monoaminergic transmission following 3-NPA intoxication. Taken together, RSe co-administration may prevent or delay the progression of HD and its associated impairments through its antioxidant, anti-inflammatory, anti-apoptotic, and neuromodulatory effects.

Treatment with tanshinone IIA suppresses disruption of the blood-brain barrier and reduces expression of adhesion molecules and chemokines in experimental autoimmune encephalomyelitis.

Tanshinone IIA (TSIIA), one of the major bioactive components of the traditional Chinese herb Salvia miltiorrhiza, has been reported to have both anti-inflammatory and immunoregulatory effects. The effect of treatment with TSIIA in multiple sclerosis, an autoimmune inflammatory neurodegenerative disease, however, remains poorly understood. In the present study, experimental autoimmune encephalomyelitis (EAE), a classical experimental model of MS, was used to investigate the therapeutic effect of TSIIA. TSIIA attenuated motor dysfunction and improved inflammation and demyelination associated with EAE in a dose-dependent manner. TSIIA also significantly reduced the levels of glial fibrillary acidic protein (GFAP) and ionized calcium-binding adapter molecule-1 (Iba-1), and protected the integrity of the blood-brain barrier (BBB) by increasing the expression of critical endothelial tight junction (TJ) proteins. TSIIA also inhibited the expression of some adhesion molecules and chemokines, which are considered to be critical for adhesion of immune cells and migration across the BBB. TSIIA was thus shown to be effective in the treatment of EAE through preventing the infiltration of immune cells into the CNS, strengthening the integrity of the BBB and decreasing the numbers of adhesion molecules and chemokines.

Glial fibrillary acidic protein is differentially expressed across cortical and subcortical regions in healthy brains and downregulated in the thalamus and caudate nucleus of depressed suicides.

There is mounting evidence to suggest aberrant astrocytic function in depression and suicide. Independent studies have reported astrocytic abnormalities in certain brain regions, but it remains unclear whether this is a brain-wide phenomenon. The present study examined this question by measuring glial fibrillary acidic protein (GFAP) expression in postmortem brain samples from suicide completers and matched non-psychiatric controls. Suicide completers were selected based on their recent characterization as low GFAP expressors in the prefrontal cortex, (Brodmann areas 8/9 and 10). Real-time PCR and immunoblotting were used to measure GFAP gene expression and protein levels in BA4 (primary motor cortex), BA17 (primary visual cortex), cerebellar cortex, mediodorsal thalamus and caudate nucleus. We found downregulation of GFAP mRNA and protein in the mediodorsal thalamus and caudate nucleus of depressed suicides compared with controls, whereas GFAP expression in other brain regions was similar between groups. Furthermore, a regional comparison including all samples revealed that GFAP expression in both subcortical regions was, on average, between 11- and 15-fold greater than in cerebellum and neocortex. Examining astrocyte morphology by immunohistochemistry showed that astrocytes in both thalamus and caudate displayed larger cell bodies and extended more ramified processes across larger domains than the previously described cortical astrocytes. This study reveals that astrocytic abnormalities are not brain wide and suggests that they are restricted to cortical and subcortical networks known to be affected in mood disorders. Additionally, our results show a greater diversity in human astrocytic phenotypes than previously thought.

Scorpion Venom Heat-Resistant Peptide Attenuates Glial Fibrillary Acidic Protein Expression via c-Jun/AP-1.

Scorpion venom has been used in the Orient to treat central nervous system diseases for many years, and the protein/peptide toxins in Buthus martensii Karsch (BmK) venom are believed to be the effective components. Scorpion venom heat-resistant peptide (SVHRP) is an active component of the scorpion venom extracted from BmK. In a previous study, we found that SVHRP could inhibit the formation of a glial scar, which is characterized by enhanced glial fibrillary acidic protein (GFAP) expression, in the epileptic hippocampus. However, the cellular and molecular mechanisms underlying this process remain to be clarified. The results of the present study indicate that endogenous GFAP expression in primary rat astrocytes was attenuated by SVHRP. We further demonstrate that the suppression of GFAP was primarily mediated by inhibiting both c-Jun expression and its binding with AP-1 DNA binding site and other factors at the GFAP promoter. These results support that SVHRP contributes to reducing GFAP at least in part by decreasing the activity of the transcription factor AP-1. In conclusion, the effects of SVHRP on astrocytes with respect to the c-Jun/AP-1 signaling pathway in vitro provide a practical basis for studying astrocyte activation and inhibition and a scientific basis for further studies of traditional medicine.

Tanshinone IIA Attenuates Chronic Pancreatitis-Induced Pain in Rats via Downregulation of HMGB1 and TRL4 Expression in the Spinal Cord.

BACKGROUND: Chronic pancreatitis (CP) is a long-standing inflammation of the exocrine pancreas, which typically results in severe and constant abdominal pain. Previous studies on the mechanisms underlying CP-induced pain have primarily focused on the peripheral nociceptive system. A role for a central mechanism in the mediation or modulation of abdominal pain is largely unknown. Tanshinone IIA (TSN IIA), an active component of the traditional Chinese medicine Danshen, exhibits anti-inflammatory properties via downregulation of the expression of high-mobility group protein B1 (HMGB1), a late proinflammatory cytokine. HMGB1 binds and activates toll-like receptor 4 (TLR4) to induce spinal astrocyte activation and proinflammatory cytokine release in neuropathic pain. OBJECTIVE: In this study, we investigated the effect of TSN IIA on pain responses in rats with trinitrobenzene sulfonic acid (TNBS)-induced CP. The roles of central mechanisms in the mediation or modulation of CP were also investigated. STUDY DESIGN: A randomized, double-blind, placebo-controlled animal trial. METHODS: CP was induced in rats by intrapancreatic infusion of trinitrobenzene sulfonic acid (TNBS). Pancreatic histopathological changes were characterized with semi-quantitative scores. The abdomen nociceptive behaviors were assessed with von Frey filaments. The effects of intraperitoneally administered TSN IIA on CP-induced mechanical allodynia were tested. The spinal protein expression of HMGB1 was determined by western blot. The spinal mRNA and protein expression of proinflammatory cytokines IL-1ß, TNF-α, and IL-6 were determined by RT-PCR and western blot, respectively. The spinal expression of the HMGB1 receptor TRL4 and the astrocyte activation marker glial fibrillary acidic protein (GFAP) were determined by western blot or immunohistological staining after intraperitoneal injection of TSN IIA or intrathecal administration of a neutralizing anti-HMGB1 antibody. RESULTS: TNBS infusion resulted in pancreatic histopathological changes of chronic pancreatitis and mechanical allodynia in rats. TSN IIA significantly attenuated TNBS-induced mechanical allodynia in a dose-dependent manner. TNBS significantly increased the spinal expression of HMGB1 and proinflammatory cytokines IL-1ß, TNF-α, and IL-6. These TNBS-induced changes were significantly inhibited by TSN IIA in a dose-dependent manner. Furthermore, TSN IIA, but not the neutralizing anti-HMGB1 antibody, significantly inhibited TNBS-induced spinal TLR4 and GFAP expression. LIMITATIONS: In addition to TLR4, HMGB1 can also bind to toll-like receptor-2 (TLR2) and the receptor for advanced glycation end products (RAGE). Additional studies are warranted to ascertain whether HMGB1 contributes to CP-induced pain through activation of these receptors. CONCLUSIONS: Our results suggest that spinal HMGB1 contributes to the development of CP-induced pain and can potentially be a therapeutic target. TSN IIA attenuates CP-induced pain via downregulation of spinal HMGB1 and TRL4 expression. Therefore, TSN IIA may be a potential anti-nociceptive drug for the treatment of CP-induced pain.

Electro-acupuncture up-regulates astrocytic MCT1 expression to improve neurological deficit in middle cerebral artery occlusion rats.

AIMS: Cerebral ischemia is one of the common diseases treated by electro-acupuncture (EA). Although the clinical efficacy has been widely affirmed, the mechanisms of action leading to the health benefits are not understood. In this study, the role of EA in modulating the lactate energy metabolism and lactate transportation was explored on the middle cerebral artery occlusion (MCAO) ischemic rat model. MAIN METHODS: Repeated EA treatments once daily for 7 days were applied to the MCAO rats and neurological function evaluation was performed. Brain tissues were harvested for lactate concentration examination, immunohistochemical staining, Western blot and qRT-PCR analyses for the expressions of lactate transporter (monocarboxylate transporter 1, MCT1) and glial fibrillary acidic protein (GFAP). KEY FINDINGS: The animal behavioral tests showed that the 7-day EA treatments significantly promoted the recovery of neurological deficits in the MCAO rats, which correlated with the enhanced lactate energy metabolism in the ischemic brain. In the cortical ischemic area of the MCAO rats, EA treatments led to the activation of astrocytes, and induced a further increase of lactate transporter (monocarboxylate transporter 1, MCT1) expression in astrocytes at both protein and mRNA levels. SIGNIFICANCE: Our results suggest that the EA treatments activated lactate metabolism in the resident astrocytes around the ischemic area and up-regulated the expression of MCT1 in these astrocytes which facilitated the transfer of intracellular lactate to extracellular domain to be utilized by injured neurons to improve the neurological deficit.

Glioprotective effects of Ashwagandha leaf extract against lead induced toxicity.

Withania somnifera (Ashwagandha), also known as Indian Ginseng, is a well-known Indian medicinal plant due to its antioxidative, antistress, antigenotoxic, and immunomodulatory properties. The present study was designed to assess and establish the cytoprotective potential of Ashwagandha leaf aqueous extract against lead induced toxicity. Pretreatment of C6 cells with 0.1% Ashwagandha extract showed cytoprotection against 25 µM to 400 µM concentration of lead nitrate. Further pretreatment with Ashwagandha extract to lead nitrate exposed cells (200 µM) resulted in normalization of glial fibrillary acidic protein (GFAP) expression as well as heat shock protein (HSP70), mortalin, and neural cell adhesion molecule (NCAM) expression. Further, the cytoprotective efficacy of Ashwagandha extract was studied in vivo. Administration of Ashwagandha extract provided significant protection to lead induced altered antioxidant defense that may significantly compromise normal cellular function. Ashwagandha also provided a significant protection to lipid peroxidation (LPx) levels, catalase, and superoxide dismutase (SOD) but not reduced glutathione (GSH) contents in brain tissue as well as peripheral organs, liver and kidney, suggesting its ability to act as a free radical scavenger protecting cells against toxic insult. These results, thus, suggest that Ashwagandha water extract may have the potential therapeutic implication against lead poisoning.

Neonatal maternal separation up-regulates protein signalling for cell survival in rat hypothalamus.

We have previously reported that in response to early life stress, such as maternal hyperthyroidism and maternal separation (MS), the rat hypothalamic vasopressinergic system becomes up-regulated, showing enlarged nuclear volume and cell number, with stress hyperresponsivity and high anxiety during adulthood. The detailed signaling pathways involving cell death/survival, modified by adverse experiences in this developmental window remains unknown. Here, we report the effects of MS on cellular density and time-dependent fluctuations of the expression of pro- and anti-apoptotic factors during the development of the hypothalamus. Neonatal male rats were exposed to 3 h-daily MS from postnatal days 2 to 15 (PND 2-15). Cellular density was assessed in the hypothalamus at PND 21 using methylene blue staining, and neuronal nuclear specific protein and glial fibrillary acidic protein immunostaining at PND 36. Expression of factors related to apoptosis and cell survival in the hypothalamus was examined at PND 1, 3, 6, 9, 12, 15, 20 and 43 by Western blot. Rats subjected to MS exhibited greater cell-density and increased neuronal density in all hypothalamic regions assessed. The time course of protein expression in the postnatal brain showed: (1) decreased expression of active caspase 3; (2) increased Bcl-2/Bax ratio; (3) increased activation of ERK1/2, Akt and inactivation of Bad; PND 15 and PND 20 were the most prominent time-points. These data indicate that MS can induce hypothalamic structural reorganization by promoting survival, suppressing cell death pathways, increasing cellular density which may alter the contribution of these modified regions to homeostasis.

Gastrodin ameliorates depressive-like behaviors and up-regulates the expression of BDNF in the hippocampus and hippocampal-derived astrocyte of rats.

Gastrodin (GAS), a main constituent of a Chinese herbal medicine Tian ma, has been shown to be effective in treating various mood disorders. The purpose of the present study was to assess the effects of GAS on alleviating depressive-like behaviors in a rat model of chronic unpredictable stress (CUS) and regulating the expression of BDNF in the hippocampus and hippocampal-derived astrocyte from Sprague-Dawley (SD) rats. Following CUS, rats were intraperitoneally administered gastrodin (50, 100, or 200 mg/kg daily) or vehicle for 2 weeks. Rats were then experienced sucrose preference test and forced swim test. The expressions of GFAP and BDNF in the hippocampus were evaluated. In addition, hippocampal astrocytes were isolated from neonatal SD rats and exposed to different concentrations of GAS (sham, 5, 10, 20, 50 and 100 µg/mL) for 48 and 72 h before the cell viability and the levels of pERK1/2 and BDNF were analyzed. Furthermore, the cell viability was also tested after exposure to serum-free condition that contain different concentrations of GAS for 48 and 72 h. GAS administration (100 and 200 mg/kg daily) reversed depressive-like behaviors in rats exposed to CUS paradigm and restored the expression of GFAP and BDNF in the hippocampus. Moreover, in vitro experiments revealed that GAS did not increase the cell viability of astrocytes but protected it from 72 h's serum-free damage at the dosage 20 µg/mL. Increased levels of ERK1/2 phosphorylation and BDNF protein were also observed after GAS (20 µg/mL) treatment for 72 h. These results indicate that gastrodin possesses antidepressant effect. The changes of the astrocyte activation and the level of BDNF may play a critical role in the pharmacological action of GAS.

Long-term treatment with standardized extract of Ginkgo biloba L. enhances the conditioned suppression of licking in rats by the modulation of neuronal and glial cell function in the dorsal hippocampus and central amygdala.

Our group previously demonstrated that short-term treatment with a standardized extract of Ginkgo biloba (EGb) changed fear-conditioned memory by modulating gene expression in the hippocampus, amygdaloid complex and prefrontal cortex. Although there are few controlled studies that support the long-term use of EGb for the prevention and/or treatment of memory impairment, the chronic use of Ginkgo is common. This study evaluated the effects of chronic treatment with EGb on the conditioned emotional response, assessed by the suppression of ongoing behavior and in the modulation of gene and protein expression. Male adult Wistar rats were treated over 28days and assigned to five groups (n=10) as follows: positive control (4mgkg(-1) Diazepam), negative control (12% Tween 80), EGb groups (0.5 and 1.0gkg(-1)) and the naïve group. The suppression of the licking response was calculated for each rat in six trials. Our results provide further evidence for the efficacy of EGb on memory. For the first time, we show that long-term treatment with the highest dose of EGb improves the fear memory and suggests that increased cAMP-responsive element-binding protein (CREB)-1 and glial fibrillary acidic protein (GFAP) mRNA and protein (P<0.001) in the dorsal hippocampus and amygdaloid complex and reduced growth and plasticity-associated protein 43 (GAP-43) (P<0.01) in the hippocampus are involved in this process. The fear memory/treatment-dependent changes observed in our study suggest that EGb might be effective for memory enhancement through its effect on the dorsal hippocampus and amygdaloid complex.

The effect of monosodium glutamate on the cerebellar cortex of male albino rats and the protective role of vitamin C (histological and immunohistochemical study).

Monosodium glutamate (MSG) is a natural constituent of many foods and was reported to have neurotoxic effects. The aim of this study was to investigate the possible toxic effect of MSG on histological and glial fibrillary acidic protein (GFAP) immunohistochemical features of cerebellar cortex of albino rats and to evaluate the possible protective role of vitamin C against this effect. Thirty rats were divided into 3 equal groups. Group I, control; Group II, treated with 3 g/kg/day of MSG and Group III, received 100 mg/kg/day of vitamin C simultaneously with MSG. After 14 days, cerebellar tissues were obtained and processed to prepare sections stained with H&E, toluidine blue. The GFAP was detected immunohistochemically. Histological examination of group II showed degenerative changes as pyknotic Purkinje and granule cells with areas of degeneration surrounded by inflammatory cells in granular layer. However, group III showed more preserved histological structure of cerebellar cortex. Statistical analysis of area percent of the GFAP immunoreaction among studied groups showed significant increase in group III when compared with group I and group II. However, a non significant increase was detected in group II when compared with group I. In conclusion, MSG has neurotoxic effect leading to degenerative changes in neurons and astrocytes in cerebellar cortex of albino rats and vitamin C supplementation could protect from these changes. Getting more attention to the constituents of food products is recommended and vitamin C could be advised to protect people from food oxidants additives.

Regulation of glioblastoma stem cells by retinoic acid: role for Notch pathway inhibition.

It is necessary to understand mechanisms by which differentiating agents influence tumor-initiating cancer stem cells. Toward this end, we investigated the cellular and molecular responses of glioblastoma stem-like cells (GBM-SCs) to all-trans retinoic acid (RA). GBM-SCs were grown as non-adherent neurospheres in growth factor supplemented serum-free medium. RA treatment rapidly induced morphology changes, induced growth arrest at G1/G0 to S transition, decreased cyclin D1 expression and increased p27 expression. Immunofluorescence and western blot analysis indicated that RA induced the expression of lineage-specific differentiation markers Tuj1 and GFAP and reduced the expression of neural stem cell markers such as CD133, Msi-1, nestin and Sox-2. RA treatment dramatically decreased neurosphere-forming capacity, inhibited the ability of neurospheres to form colonies in soft agar and inhibited their capacity to propagate subcutaneous and intracranial xenografts. Expression microarray analysis identified ∼350 genes that were altered within 48 h of RA treatment. Affected pathways included retinoid signaling and metabolism, cell-cycle regulation, lineage determination, cell adhesion, cell-matrix interaction and cytoskeleton remodeling. Notch signaling was the most prominent of these RA-responsive pathways. Notch pathway downregulation was confirmed based on the downregulation of HES and HEY family members. Constitutive activation of Notch signaling with the Notch intracellular domain rescued GBM neurospheres from the RA-induced differentiation and stem cell depletion. Our findings identify mechanisms by which RA targets GBM-derived stem-like tumor-initiating cells and novel targets applicable to differentiation therapies for glioblastoma.

Bone marrow mesenchymal stem cells and electroacupuncture downregulate the inhibitor molecules and promote the axonal regeneration in the transected spinal cord of rats.

Our previous study has reported that electroacupuncture (EA) promotes survival, differentiation of bone marrow mesenchymal stem cells (MSCs), and functional improvement in spinal cord-transected rats. In this study, we further investigated the structural bases of this functional improvement and the potential mechanisms of axonal regeneration in injured spinal cord after MSCs and EA treatment. Five experimental groups, 1) sham control (Sham-control); 2) operated control (Op-control); 3) electroacupuncture treatment (EA); 4) MSCs transplantation (MSCs), and 5) MSCs transplantation combined with electroacupuncture (MSCs + EA), were designed for this study. Western blots and immunohistochemical staining were used to assess the fibrillary acidic protein (GFAP) and chondroitin sulfate proteoglycans (CSPGs) proteins expression. Basso, Beattie, Bresnahan (BBB) locomotion test, cortical motor evoked potentials (MEPs), and anterograde and retrograde tracing were utilized to assess cortical-spinal neuronal projection regeneration and functional recovery. In the MSCs + EA group, increased labeling descending corticospinal tract (CST) projections into the lesion site showed significantly improved BBB scales and enhanced motor evoked potentials after 10 weeks of MSCs transplant and EA treatment. The structural and functional recovery after MSCs + EA treatment may be due to downregulated GFAP and CSPGs protein expression, which prevented axonal degeneration as well as improved axonal regeneration.

Anti-amnesic effect of ESP-102 on Aß(1-42)-induced memory impairment in mice.

The aim of this study was to characterize the effects of ESP-102 on the memory impairments and pathological changes induced by amyloid-ß (Aß)(1-42) peptide in mice. The ameliorating effect of ESP-102 on memory impairment was investigated using the passive avoidance and the Morris water maze tasks, and the pathological changes were identified by immunohistochemistry and western blotting. Aß(1-42) peptide (3µg/3µl) was administered by intracerebroventricular injection. By the single administration of ESP-102 (100mg/kg, p.o), the memory impairment induced by Aß(1-42) peptide was significantly attenuated (P<0.05). Moreover, ESP-102 (100mg/kg, p.o) significantly inhibited acetylcholinesterase (AChE) activity in the hippocampus compared to the Aß(1-42) peptide-injected control group. In the subchronic treatment study, ESP-102 (50 or 100mg/kg/day, p.o) administration for seven days ameliorated the memory impairments induced by Aß(1-42) peptide. Moreover, ESP-102 inhibited lipid peroxidation induced by Aß(1-42) peptide in the hippocampus. Aß(1-42)-induced increases in the expression of GFAP (an astrocyte marker) and inducible nitric oxide synthase (iNOS) in the hippocampal region were also attenuated by ESP-102 treatment. These results suggest that the ameliorating effect of ESP-102 on Aß(1-42) peptide-induced memory impairment is mediated via its AChE inhibitory, antioxidative, and/or anti-inflammatory activities.

Transgenic mice with astrocyte-targeted production of interleukin-6 are resistant to high-fat diet-induced increases in body weight and body fat.

Interleukin-6 (IL-6) is a major cytokine involved in both normal physiological brain functions and underlying significant neuropathology. IL-6 has been suggested to play a role in the control of body weight but the results are somewhat controversial. In this study we have challenged transgenic mice with astrocyte-targeted IL-6 expression (GFAP-IL6 mice) with a high-fat diet (55% kcal from fat) versus a control diet (10%). The results demonstrate that the GFAP-IL6 mice are resistant to high-fat diet-induced increases in body weight and body fat, apparently without altering food intake and with no evidences of increased sympathetic tone. The high-fat diet-induced impaired responses to an insulin tolerance test (ITT), and to an oral glucose tolerance test (OGTT) in both genotypes. The GFAP-IL6 mice did not differ from littermate wild-type (WT) mice in ITT, but they were more glucose intolerant following the high-fat diet feeding. In summary, the present results demonstrate that brain-specific IL-6 controls body weight which may be a significant factor in physiological conditions and/or in diseases causing neuroinflammation.

Aging exacerbates intracerebral hemorrhage-induced brain injury.

Aging may be an important factor affecting brain injury by intracerebral hemorrhage (ICH). In the present study, we investigated the responses of glial cells and monocytes to intracerebral hemorrhage in normal and aged rats. ICH was induced by microinjecting autologous whole blood (15 microL) into the striatum of young (4 month old) and aged (24 month old) Sprague-Dawley rats. Age-dependent relations of brain tissue damage with glial and macrophageal responses were evaluated. Three days after ICH, activated microglia/macrophages with OX42-positive processes and swollen cytoplasm were more abundantly distributed around and inside the hemorrhagic lesions. These were more dramatic in aged versus the young rats. Western blot and immunohistochemistry analyses showed that the expression of interleukin-1beta protein after ICH was greater in aged rats, whereas the expression of GFAP and ciliary neurotrophic factor protein after ICH was significantly lower in aged rats. These results suggest that ICH causes more severe brain injury in aged rats most likely due to overactivation of microglia/macrophages and concomitant repression of reactive astrocytes.

Dietary taurine supplementation ameliorates diabetic retinopathy via anti-excitotoxicity of glutamate in streptozotocin-induced Sprague-Dawley rats.

The purpose of this study was to investigate whether taurine ameliorate the diabetic retinopathy, and to further explore the underlying mechanisms. The Sprague-Dawley rats were injected with streptozotocin to establish experimental diabetic model, then fed without or with 1.2% taurine for additional 4-12 weeks. After that, the protective effects of dietary taurine supplementation on diabetic retinopathy were estimated. Our results showed that chronic taurine supplement effectively improved diabetic retinopathy as changes of histopathology and ultrastructure. The supplementation could not lower plasma glucose concentration (P > 0.05), but caused an elevation in taurine content and a decline in levels of glutamate and gamma-aminobutyric acid (GABA) in diabetic retina (P < 0.05). Moreover, chronic taurine supplementation increased glutamate transporter (GLAST) expression (P < 0.05), decreased intermediate filament glial fibrillary acidic protein (GFAP) and N-methyl-D: -aspartate receptor subunit 1 (NR1) expression in diabetic retina (P < 0.05). These results demonstrated that chronic taurine supplementation ameliorates diabetic retinopathy via anti-excitotoxicity of glutamate in rats.

Differential effects of reproductive and hormonal state on basic fibroblast growth factor and glial fibrillary acid protein immunoreactivity in the hypothalamus and cingulate cortex of female rats.

Morphological changes in astrocytes occur in a number of brain regions including the hypothalamus and hippocampal regions as a function of hormonal and reproductive state. Because basic fibroblast growth factor has been shown to play an important role in morphological changes in astrocytes, we investigated whether basic fibroblast growth factor immunoreactivity would also be influenced by reproductive state and circulating gonadal steroids. To do this we compared astrocytic basic fibroblast growth factor and glial fibrillary acid protein immunoreactivity in hypothalamic nuclei and the cingulate cortex, area 2 among groups of cycling, late pregnant and lactating rats as well as in ovariectomized and ovariectomized hormone-replaced females. Significant differences in both basic fibroblast growth factor and glial fibrillary acid protein immunoreactivity were observed across groups in the supraoptic nucleus, parvocellular paraventricular nucleus, medial preoptic area of the hypothalamus and cingulate cortex 2. The pattern of change in basic fibroblast growth factor and glial fibrillary acid protein immunoreactivity varied across regions both in direction and magnitude. For example, although in the supraoptic nucleus ovariectomized rats had lower levels of basic fibroblast growth factor-ir than cycling females, this pattern was reversed within cingulate cortex. Overall the results of this study suggest that reproductive and hormonal states are associated with robust changes in basic fibroblast growth factor and glial fibrillary acid protein immunoreactivity in a number of brain areas but that the changes observed vary in magnitude as well as direction from one brain region to another.

[Gene reversion of induced differentiation of adult human bone marrow-derived mesenchymal stem cells into neuron-like cells].

OBJECTIVE: To observe gene reversion during differentiation of human adult bone marrow-derived mesenchymal stem cells (MSCs) into neuron-like cells induced by Shenqiye. METHODS: The MSCs were separated, cultured and expanded in the culture medium and induced to differentiate into neuron-like cells with Shenqiye. The expressions of neuron-specific enolase (NSE), neurofilament (NF), and glial fibrillary acidic protein (GFAP) were detected by immunocytochemical method, and the changes of 10 genes of the cells after differentiation were detected by reverse transcriptional PCR. RESULTS: The MSCs exhibited neuronal phenotype when treated with Shenqiye and the neuron-like cells were positive for expressions of NSE and NF but not for glial astrocyte marker GFAP. After withdrawal of Shenqiye from the medium, the neuron-like cells were reversed to MSC, flat or spindal in morphology. The gene expression profiles of the redifferentiated cells were similar to those of undifferentiated MSCs. CONCLUSION: Shenqiye can induce MSC differentiation into neuron-like cells during and after which gene reversion may occur.