Glial Fibrillary Acidic Protein Expression Research Articles

Bihemispheric IDH-Wildtype Glioblastoma with Unilateral FGFR3-TACC3 Fusion in Patient with Breast Cancer History: A Case Report and Literature Review

Abstract Introduction/Objective Adult IDH-wild type glioblastomas comprise a heterogeneous spectrum of neoplasms, characterized by poor prognosis and resistance to the chemoradiotherapy. For WHO integrated diagnosis classification and to establish treatment options, molecular analysis is necessary. Herein, we present a case of a glioblastoma, IDH-wildtype with involvement of both cerebral hemispheres and an uncharacteristic in-frame fusion limited to one hemisphere. Methods/Case Report The patient is a 52-year-old woman with past medical history of metastatic breast cancer who presented with headache and worsening facial pain. Brain magnetic resonance imaging brain demonstrated a right frontal lobe lesion with vasogenic edema. The patient was treated with Gamma Knife radiosurgery. Scans revealed enlargement and a new left frontal lobe lesion. Bihemispheric tumor resection and GammaTile placement was undertaken. Results (if a Case Study enter NA) Histologically, the tumor was composed of hypercellular astrocytes, microvascular proliferation, and necrosis with no evidence of metastatic disease. Immunohistochemistically, neoplastic cells showed glial fibrillary acidic protein expression and elevated Ki-67 proliferation index. Molecular examination revealed in the right hemisphere lesion post-radiation (1) FGFR3::TACC3 (exon 17::exon 11) fusion and (2) TERT promoter, while the left hemisphere lesion which did not receive radiation showed clinically relevant variants in (1) TERT promoter, (2) TP53, (3) NF1, and (3) PIK3CA without identification of a fusion. An integrated diagnosis of glioblastoma, IDH- wildtype, CNS WHO grade 4 was established bilaterally. Conclusion The fibroblast growth factor receptor 3 (FGFR3)-transforming acidic coiled-coil 3 (TACC3) fusion is identified as a rare molecular feature in glioblastomas with an estimated prevalence of 4%. Clinical trials suggest that F3T3-positive tumors have a better prognosis than those without the translocation. The identification of the oncogenic FGFR3-TACC3 fusion highlights the possibility of identifying patients potentially responsive to targeted therapy with FGFR kinase inhibitors. The significance of the molecular differences in the right and left hemisphere lesions is uncertain; glioblastomas are heterogeneous tumors with intra-and intertumoral heterogeneity but it may suggest independent origins.

Semaglutide ameliorates Alzheimer's disease and restores oxytocin in APP/PS1 mice and human brain organoid models

AimsTo investigate the therapeutic effects and mechanisms of Semaglutide in Alzheimer's disease (AD), and identify its potential targets. MethodsWe systematically evaluated the effect of Semaglutide on Alzheimer's disease (AD), using both mice and human organoid models. ResultsBehavioral analyses on APP/PS1 mice demonstrated that Semaglutide improved the cognitive capabilities, particularly in the learning and memory domains. Biochemical investigations further highlighted its role in reducing amyloid plaque deposition and down-regulating the expression of glial fibrillary acidic protein (GFAP) and ionized calcium binding adaptor molecule 1 (Iba1) expression in the mouse brain tissues. Meanwhile, oxytocin (OXT) was up-regulated after Semaglutide treatment. Subsequent studies using human AD-brain organoids (BOs) models revealed that, upon Semaglutide treatment, these AD-BO models also exhibited reduced levels of amyloid-beta (Aβ), phosphorylated Tau (p-Tau) and GFAP expression as well as increased OXT level. ConclusionsSemaglutide can ameliorate Alzheimer's disease in pre-clinical models, suggesting the promising therapeutic potential in AD patients.

Effects of Environmental Noise Stress on Mouse Metabolism

Environmental noise is associated with various health outcomes. However, the mechanisms through which these outcomes influence behavior and metabolism remain unclear. This study investigated how environmental noise affects the liver, adipose tissue, and brain metabolic functions, leading to behavioral and body weight changes. Mice were divided into a noise group exposed to construction noise and an unexposed (control) group. Behavior and body weight changes were monitored over 50 days. Early changes in response to noise exposure were assessed by measuring plasma cortisol and glial fibrillary acidic protein expression in brain tissues on days 1, 15, and 30. Chronic responses, including changes in lipoprotein and fat metabolism and neurotransmitters, were investigated by analyzing serum lipoprotein levels and body fat mass and evaluating liver, fat, and brain tissue after 50 days. The noise group showed higher locomotor activity and reduced anxiety in the open-field and Y-maze tests. Noise exposure caused an initial weight loss; however, chronic noise increased fat mass and induced adipocyte hypertrophy. Our findings underscore the role of environmental noise-induced stress in augmenting locomotor activity and reducing anxiety in mice through neurotransmitter modulation while increasing the risk of obesity by decreasing HDL cholesterol levels and promoting adipocyte hypertrophy.

Folic acid ameliorates high glucose–induced neurotoxicity in human forebrain organoids: Insights from proteomics

AbstractPregestational diabetes (PGDM) has been associated with an elevated risk of congenital abnormalities, particularly those affecting the nervous system. The efficacy of folic acid (FA) supplementation in reducing the incidence of neurodevelopmental damage caused by PGDM has been well documented. However, the exact mechanism is unclear. Here, a human forebrain organoid model, which replicates the three‐dimensional structure of the early fetal neural tissue, was employed to study the neuroprotective effects of FA in PGDM. In this study, the forebrain organoids were cultured at high glucose (HG) concentrations from Days 20 to 40 with or without FA. Immunostaining revealed that the supplementation of FA significantly decreased HG‐induced neuron apoptosis. The proteomics examination suggested HG caused an increase in glial fibrillary acidic protein expression, a marker of astrocytes, leading to the upregulation of metallothionein expression and perturbation of mineral absorption, whereas FA reversed this effect. Proteomics analysis further showed that FA reduced HG‐induced cell migration. Moreover, Western blot analysis verified that FA mitigated HG‐induced apoptosis and cell migration via AMPK/FOXO pathway. Overall, current findings indicate that FA, as a functional food ingredient, has a protective effect on HG‐induced abnormal fetal neurodevelopment.

Impact of Epstein-Barr Virus Nuclear Antigen 1 on Neuroinflammation in PARK2 Knockout Mice.

This study aimed to explore the intricate relationship between mitochondrial dysfunction, infection, and neuroinflammation, focusing specifically on the impact of pathogenic epitopes of the Epstein-Barr Virus (EBV) nuclear antigen 1 (EBNA1) in a mouse model of mitochondrial dysfunctions. The investigation included female middle-aged PARK2-/- and C57BL/6J wild-type mice immunized with EBNA1386-405 or with active experimental autoimmune encephalomyelitis (EAE) induction by the myelin oligodendrocyte glycoprotein (MOG)35-55 peptide. The PARK2-/- mice developed more severe EAE than the wild-type mice. Following immunization with EBNA1386-405, only PARK2-/- exhibited symptoms resembling EAE. During the acute phase, PARK2-/- mice immunized with either MOG35-55 or EBNA1386-405 exhibited a similar infiltration of the T cells and macrophages in the spinal cord and decreased glial fibrillary acidic protein (GFAP) expression in the brain. However, the EBNA1386-405 -immunized PARK2-/- mice showed significantly increased frequencies of CD8a+ T cells and CD11c+ B cells, and distinct cytokine profiles in the periphery compared to the wild-type controls. These findings highlight the role of EBV in exacerbating inflammation, particularly in the context of mitochondrial deficiencies.

Early life seizures and olfactory communication in rats.

Early life seizures (ELS) are commonly associated with autism spectrum disorder (ASD); however, the exact role of ELS in the pathology is unknown. Prior studies have demonstrated social deficits, a core feature of ASD, following ELS; consequently, alterations in sensory modalities may contribute to the overall social deficits. Considering the speculated contribution of sensory deficit to social communication, we examined the developmental consequences of early postnatal kainic acid (KA)-induced seizures on olfactory preference and neural markers in the olfactory bulb in both male and female Sprague Dawley rats. KA-induced seizures or saline was administered. Rats were then exposed to a series of biologically relevant scents including male scent, female scent, nest scent, and phenylethylamine during the juvenile period and again during adulthood. Alterations in sensory modalities were expected to be expressed via abnormal preference for certain scents and/or production of abnormal ultrasonic vocalizations in response to scents. The olfactory bulbs were also assessed for the biologically relevant markers glial fibrillary acidic protein (GFAP) and calcium/calmodulin-dependent protein kinase II (CAMKII). Our findings resulted in no significant differences in olfactory preference following ELS for juveniles or adults compared to controls. Similarly, there were no differences in GFAP expression or the ratio of phosphorylated CAMKII to CAMKII in either olfactory bulb. Interestingly, despite a lack of treatment differences, different scents were shown to elicit different responses in juvenile rats, yet these differences subsided in adulthood. Overall, the results of this study suggest that olfaction does not contribute to socialization deficit following ELS within the KA model.

Evaluation of the Choroid Plexus Epithelium Inflammation TLR4/NF-κB/NKCC1 Signal Pathway Activation in the Development of Hydrocephalus.

Hydrocephalus is characterized by secretion, circulation, and absorption disorder of cerebrospinal fluid (CSF) with high morbidity and complication rate. The relationship between inflammation and abnormal secretion of CSF by choroid plexus epithelium (CPE) had received more attention. In this study, we aim to detect the role of Toll-like receptor 4/nuclear factor-kappa B/Na+/K+/2Cl-cotransporter 1(TLR4/NF-κB/NKCC1) signal pathway in the development of hydrocephalus. Hydrocephalus was induced in adult rats (8 weeks) by intracisternal kaolin injection, then pyrrolidinedithiocarbamate (PDTC) and bumetanide were administrated to the rats mode. Then the rat model was evaluated, and ventricular volume was calculated at different time points. Then CPE, cortex, preventricular tissue, and CSF were obtained. Protein expressions of TLR-4, NKCC/serine-threonine STE20/SPS1-related, proline-alanine-rich kinase (SPAK), pNKCC1, pSPAK, GFAP, AQP1, and AQP4 were measured by RT-PCR, western blot, and immunofluorescence (IF) stains in CPE, respectively. Our data showed that inflammation factors tumor necrosis factor-(TNF-α), interleukin 18(IL-18), and glial fibrillary acidic protein (GFAP) concentrations were significantly higher in the model group than in controls. The TLR4/NF-κB/NKCC1 signal pathway were actived by NF-κB-p65, NKCC1, pNKCC1- pSPAK complex, and Aquaporin1 (AQP1) high expression. PDTC and bumetanide use can help regular TLR4/NF-κB/NKCC1 expression and reduced AQP1 expression by down-regulate NF-B-p65 and inhibiting NKCC1, respectively. As a result, the treatment groups alleviated CPE abnormal secretion and ventricle enlargement. These results confirmed that the inflammatory reaction contributes TLR4/NF-κB/NKCC1 mediated CPE abnormal secretion and consequent hydrocephalus. Regulation of TLR4/NF-κB/NKCC1 and AQP1 can prevent this process. Our study provides a strong rationale for further exploring alleviating CPE abnormal secretion as a therapeutic perspective of hydrocephalus.

Regulatory role of electroacupuncture on satellite glial cell activity in the colon and dorsal root ganglion of rats with irritable bowel syndrome.

To investigate the role of satellite glial cells in irritable bowel syndrome (IBS) and the effect of electroacupuncture (EA) at the Tianshu (ST25) and Shangjuxu (ST37) combination. A model for visceral hypersensitivity in IBS was induced through colorectal distension (CRD) stimulation. Clean-grade male Sprague-Dawley (SD) rats were randomly divided into four groups: a normal group (NG), a model group (MG), an electroacupuncture group (EA), and a glial cell inhibitor group (FCA). Bilateral EA (2/100 Hz, 1 mA, 30 min) was administered at the Tianshu (ST25) and Shangjuxu (ST37) in week 6. Abdominal withdrawal reflex (AWR) scores were used to assess the behavioral response associated with visceral hyperalgesia, while hematoxylin-eosin staining was employed to evaluate pathological changes in the colon. The protein and mRNA levels of glial fibrillary acidic protein (GFAP) in the colon and colon-related dorsal root ganglion (DRG) were analyzed using immun-ofluorescence, immun-ohistochemistry, Western blotting, real-time polymerase chain reaction. The impact of EA on electrophysiological properties of colon-related DRG neurons was observed through whole-cell patch clamp analysis. EA significantly reduced the visceral pain behavior scores in rats with IBS in response to graded (20, 40, 60, 80 mm Hg) CRD stimulation. Additionally, EA downregulated the protein and mRNA expression levels of GFAP in the colon and colon-related DRG of rats with IBS. EA also regulated the resting membrane potential, rheobase and action potential of colon-related DRG neurons in rats with IBS. EA can regulate the excitatory properties of colon-related DRG neurons by downregulating the protein and mRNA expression of GFAP in the colon and colon-related DRG, indicating a potential neurobiological mechanism by which EA relieves visceral hypersensitivity in rats with IBS.

A Systematic Review of Delta-9-Tetrahydrocannabinol (∆9-THC) in Astrocytic Markers.

Astrocytic reactivity in substance use disorders (SUDs) has been extensively studied, yet the molecular effect of delta-9-tetrahydrocannabinol (∆9-THC, the main psychoactive compound in cannabis) on glial cells, especially astrocytes, remains poorly understood. Exploring ∆9-THC's impact on astrocytic markers can provide insight into its effects on brain functions such as homeostasis, synaptic transmission, and response to neuronal injury. This systematic review synthesizes findings from studies investigating ∆9-THC's impact on astrocytic markers. A systematic review was conducted using EMBASE, Medline, and PsychoInfo via the OvidSP platform. Studies reporting astrocytic markers following ∆9-THC exposure in animals and humans were included. Data were extracted from twelve eligible full-text articles, and the risk of bias was assessed using the Systematic Review Center for Laboratory Animal Experimentation. This research identified several astrocytic markers, including glial fibrillary acidic protein (GFAP), nestin, and glutamate-aspartate transporter (GLAST). Both GFAP and nestin expressions increased in adulthood following adolescence and adult ∆9-THC exposure. An increase in GLAST expression was also noted during early development after ∆9-THC exposure. This review indicates varying levels of astrocytic reactivity to ∆9-THC across different developmental stages, including adolescence and adulthood. ∆9-THC appears to impact maturation, particularly during early developmental stages, and exhibits sex-dependent effects.

Temperature control during pars plana vitrectomy.

To evaluate the impact of temperature-controlled pars plana vitrectomy (PPV) on structural and functional outcomes in a rabbit eye model in vivo. Ten healthy New Zealand White rabbits underwent temperature-controlled PPV in the right eye (group A), using a device specifically designed to heat the infusion fluid/air and integrated into the vitrectomy machine, and conventional PPV in the left eye (group B). Both eyes received ophthalmic examination and electroretinography (ERG) before and 1week postoperatively. After 1-week ERG, rabbits were enucleated and then sacrificed. Histological and immunohistochemical examinations were performed on enucleated eyes and expression of glial fibrillary acidic protein (GFAP) and vimentin investigated. Postoperatively, only group B showed significantly decreased amplitude and increased latency of a-wave at 3cd·s/m2 (p = 0.001 and 0.005, respectively). Significant increase of b-wave latency at 0.01cd·s/m2 was detected in both groups (p = 0.019 and 0.023, respectively). Postoperatively, amplitude of oscillatory potentials (OPs) increased significantly in group A (p = 0.023) and decreased in group B. In both groups, OPs latency significantly increased at 1-week test (P < 0.05). A greater number of eyes without structural retinal alterations was detected in group A compared to group B (6 vs 5, respectively). GFAP expression was higher in group B than group A, even if the difference was not statistically significant. Temperature-controlled PPV resulted in more favorable functional and structural outcomes in rabbit eyes compared with conventional PPV, supporting the potential beneficial role of the intraoperative management of intraocular temperature in vitreoretinal surgery.

Chinese Herbs for Inducing Rat Bone Marrow Mesenchymal Stem Cells Differentiated into Neuron-Like Cells

The purpose of this study was to observe the influence of two Chinese herbs of ligustrazine and Xuefuzhuyu injection on neuron-like cells differentiation from rat bone marrow mesenchymal stem cells (BMSCs) respectively. Most primarily cultured BMSCs adhered to the wall at 3 days after cultured, which proliferated faster after passaged, and the 5th passage of cells were mostly purified into BMSCs. In the present study, the 5th passage of BMSCs were (97.51±1.22) % CD44 positive, but negative for CD45, which were identified by immunocytochemical technique. Serum-free low-sugar Dulbecco’s modified Eagle’s medium (L-DMEM) contains 1.25 g/L ligustrazine and 3.0 g/L Xuefuzhuyu injection were used to induce the 5th passage of BMSCs respectively in vitro. Neuron-like cells with prominence and bifurcation could be detected after induction under an inverted phase contrast microscope. The immunocytochemical method showed that nestin and neuron-specific enolase (NSE) were positive in neuron-like cells, but without glial fibrillary acidic protein (GFAP) expression. Both ligustrazine and Xuefuzhuyu injection have the potential for inducing neuron-like cells differentiation from rat bone marrow mesenchymal stem cells respectively. Compared with Xuefuzhuyu injection-induced cells, neuron-like cells induced with ligustrazine might be better in the level of morphological changes, as well as nestin and NSE expression.

NDRG2 regulates glucose metabolism and ferroptosis of OGD/R-treated astrocytes by the Wnt/β-catenin signaling.

Ischemic stroke is one main type of cerebrovascular disorders with leading cause of death and disability worldwide. Astrocytes are the only nerve cell type storing glycogen in the brain, which regulate the glucose metabolism and handle the energy supply and survive of neurons. Astrocyte ferroptosis contributes to neuron injury in brain disorders. N-myc downstream-regulated gene 2 (NDRG2) has been implicated in the progression of brain diseases, including ischemic stroke. However, whether NDRG2 could affect the glucose metabolism and ferroptosis of astrocytes during ischemic stroke remains largely unknown. Mouse astrocytes were treated with oxygen-glucose deprivation/reoxygenation (OGD/R) to establish the in vitro model. Glial fibrillary acidic protein, NDRG2, Wnt3a and β-catenin expression levels were detected by immunofluorescence staining and western blot analyses. Glucose metabolism was investigated by glucose uptake, lactate production, nicotinamide adenine dinucleotide phosphate hydrogen/nicotinamide adenine dinucleotide phosphate (NADPH/NADP+), ATP and glycolysis enzymes (HK2, PKM2 and lactate dehydrogenase A [LDHA]) levels. Ferroptosis was assessed via reactive oxygen species (ROS), glutathione (GSH), iron and ferroptosis-related markers (GPX4 and PTGS2) contents. Glycolysis enzymes and ferroptosis-related markers levels were measured via western blot. NDRG2 expression was elevated in OGD/R-induced astrocytes. NDRG2 overexpression aggravated OGD/R-induced loss of glucose metabolism through reducing glucose uptake, lactate production, NADPH/NADP+ and ATP levels. NDRG2 upregulation exacerbated OGD/R-caused reduction of glycolysis enzymes (HK2, PKM2 and LDHA) levels. NDRG2 promoted OGD/R-induced ferroptosis of astrocytes by increasing ROS, iron and PTGS2 levels and decreasing GSH and GPX4 levels. NDRG2 overexpression enhanced OGD/R-induced decrease of Wnt/β-catenin signaling activation by reducing Wnt3a and β-catenin expression. NDRG2 silencing played an opposite effect. Inhibition of Wnt/β-catenin signaling activation by IWR-1 attenuated the influences of NDRG2 knockdown on glucose metabolism, glycolysis enzymes levels and ferroptosis. These findings demonstrated that NDRG2 contributes to OGD/R-induced inhibition of glucose metabolism and promotion of ferroptosis in astrocytes through inhibiting Wnt/β-catenin signaling activation, which might be associated with ischemic stroke progression.

“Investigation of the potential cellular changes induced by magnesium sulfate and salubrinal in a lipopolysaccharide-induced chorioamnionitis model”

Chorioamnionitis is closely associated with preterm labor and poses a significant public health concern. In this pathological process where inflammation plays a key role, intracellular mechanisms such as endoplasmic reticulum stress are crucial. In this study, we aimed to explore the potential positive outcomes of the combined use of salubrinal (SLB) with magnesium (Mg) treatment in chorioamnionitis.Thirty pregnant rats were divided into 5 groups as: Control, LPS (1 mg/kg), LPS + SLB (1 mg/kg), LPS + Mg (Dhaka protocol), LPS + SLB + Mg. Rats were sacrificed 4 h after LPS administration, then placental and fetal brain tissues were collected.LPS administration enhanced the levels of tumor necrosis factor-alpha, vascular endothelial growth factor, caspase-3 immunoexpressions, BAX, eukaryotic initiation factor 2-alpha, s100, and glial fibrillary acidic protein expressions and lowered BCL2 expressions in the placenta or fetal brains. SLB and Mg treatments were observed to reverse all these findings, and the most significant positive effect was in the LPS + SLB + Mg group.The known anti-inflammatory activity of Mg, when used with SLB, preventing the transition to apoptosis and increasing antioxidant enzyme activity, as identified in this study, can contribute significantly to the literature. However, these results need to be supported by additional molecular studies.

Exogenous leptin alleviates glutamate-excitotoxic injury caused by cerebral ischemia–reperfusion in mice by affecting the expression of glutamate transporters

Ischemic stroke is characterized by high morbidity and mortality and a lack of effective therapeutic interventions. Leptin plays an important role in regulating oxidative stress, angiogenesis, hematopoiesis, etc. Although recent studies have found a neuroprotective effect of leptin, little is known about its role in cerebral ischemia. This study explores the possible roles and potential preventative mechanisms of leptin in cerebral ischemia–reperfusion injury (CIRI). An in vivo middle cerebral artery occlusion/reperfusion (MCAO/R) mouse model was used to replicate the CIRI model, low (0.5 mg/kg), medium (1 mg/kg) and high (2 mg/kg) concentrations of leptin were injected intraperitoneally immediately after inserting the embolic line. After 1.5 h of ischemia and 24 h of reperfusion, we examined the neural function of the mice, collected brain tissue for histological examination, and screened for the optimal concentrations of leptin intervention. On this basis, we observed the changes of cortical apoptosis injury, intracellular calcium fluorescence intensity and astrocyte glial fibrillary acidic protein (GFAP) expression and morphological changes. In addition, we also tested the expression of transporters and metabolism-related enzymes (VGLUT-1, VGLUT-2, GLAST, GLT-1, GS, ATP1α1), the expression of inflammatory factors and the content of glutamate (Glu). Compared with the I/R group, we found that leptin improved neurological deficits, reduced the area of infarcts, maintained the normal morphology of astrocytes (AST), downregulated the expression of VGLUT-1, and upregulates the expression of GLT-1 and GLAST, thereby reducing the content of Glu in the synaptic cleft. Our studies suggest that leptin may have a neuroprotective effect by decreasing the excitotoxicity of glutamate.

Neurological recovery in rats with portocaval anastomosis-induced hepatic encephalopathy treated with leuprolide acetate, a GnRH agonist.

Hepatic encephalopathy (HE) is a neuropsychiatric complication of acute liver failure or chronic liver injury. Liver dysfunction impairs ammonia detoxification, allowing it to cross the blood-brain barrier (BBB) and disrupt brain function. The hippocampus becomes a crucial target during elevated ammonia levels, causing spatial memory impairment and decreased learning ability. Leuprolide acetate (LA), a GnRH agonist, has been implicated in neuroprotection and neuroregeneration in several regions of the central nervous system (CNS) including hippocampus. In this study, we aim to evaluate the effects of LA treatment on hippocampus of rats with HE induced by portocaval anastomosis (PCA) trough cognitive tests, histology analysis and expression of neuronal recovery marker proteins, such as neurofilament (NF200) and neurabin II, and astrocyte marker glial fibrillary acidic protein (GFAP). Rats were divided into three groups: SHAM, portocaval anastomosis with saline solution (PCA + SS) and portocaval anastomosis treated with LA (PCA + LA). To evaluate learning and spatial memory elevated T-maze (ETM) and Y-maze test (YMT) were respectively used. Results indicated that LA-treated rats performed significantly better in ETM and YMT than untreated rats. Histological analysis of hippocampus showed increased neuron density, nuclear area, and layer thickness in dentate gyrus of PCA + LA group compared to PCA + SS. Additionally, neurabin II and NF200 expression were higher in LA-treated rats, while GFAP expression was elevated in the PCA + SS group compared to control and PCA + LA groups. In conclusion, LA enhances hippocampal neuron recovery and reduces astrogliosis, suggesting its potential as a therapeutic intervention for attenuating hippocampal damage during HE.

Acute ocular hypertension in the living human eye: Model description and initial cellular responses to elevated intraocular pressure

This initial methods study presents the initial immunohistochemical and transcriptomic changes in the optic nerve head and retina from three research-consented brain-dead organ donors following prolonged and transient intraocular pressure (IOP) elevation. In this initial study, research-consented brain-dead organ donors were exposed to unilateral elevation of IOP for 7.5 h (Donor 1), 30 h (Donor 2), and 1 h (Donor 3) prior to organ procurement. Optic nerve tissue and retinal tissue was obtained following organ procurement for immunohistological and transcriptomic analysis.Optic nerve sections in Donor 1 exposed to 7.5-hours of unilateral sub-ischemic IOP elevation demonstrated higher levels of protein expression of the astrocytic marker, glial fibrillary acidic protein (GFAP), within the lamina cribrosa with greatest expression inferior temporally in the treated eye compared to control. Spatial transcriptomic analysis performed on optic nerve head tissues from Donor 2 exposed to 30 h of unilateral IOP elevation demonstrated differential transcription of mRNA across laminar and scleral regions. Immunohistochemistry of retinal sections from Donor 2 exhibited higher GFAP and IBA1 expression in the treated eye compared with control, but this was not observed in Donor 3, which was exposed to only 1-hour of IOP elevation. While there were no differences in GFAP protein expression in the retina following the 1-hour IOP elevation in Donor 3, there were higher levels of transcription of GFAP in the inner nuclear layer, and CD44 in the retinal ganglion cell layer, indicative of astrocytic and Müller glial reactivity as well as an early inflammatory response, respectively.We found that transcriptomic differences can be observed across treated and control eyes following unilateral elevation of IOP in brain dead organ donors. The continued development of this model affords the unique opportunity to define the acute mechanotranscriptomic response of the optic nerve head, evaluate the injury and repair mechanisms in the retina in response to IOP elevation, and enable correlation of in vivo imaging and functional testing with ex vivo cellular responses for the first time in the living human eye.

BMP10 accelerated spinal astrocytic activation in neuropathic pain via ALK2/smad1/5/8 signaling.

Astrocytic activation in the spinal dorsal horn contributes to the central sensitization of neuropathic pain. Bone morphogenetic protein (BMP) 10, one of the BMPs highly expressed in the central nervous system, has been demonstrated to have an accelerated effect on astrocytic activation. This study aimed to investigate the functional effects of BMP10 on the activation of astrocytes in the spinal dorsal horn of animal model of neuropathic pain and to explore potential mechanisms involved in this process. A neuropathic pain mice model was established using the spared nerve injury (SNI). Western blot analysis was performed to detect the expressional levels of BMP10, activin receptor-like receptor 2 (ALK2), Smad1/5/8, phosphorylated Smad1/5/8, and glial fibrillary acidic protein (GFAP). Immunofluorescence staining was used to detect BMP10, ALK2, and GFAP distribution and expression. The behavioral changes in mice were evaluated using paw withdrawal threshold (PWT), thermal withdrawal latency (TWL), and open field test (OFT). The BMP10 siRNA, Smad1 siRNA, BMP10 peptide, and ALK2-IN-2 (ALK2 inhibitor) were intrathecally administrated to mice. A model of lipopolysaccharide (LPS)-stimulated astrocytes was established to investigate the effect of Smad1. The transfection efficiency of siRNAs was detected by western blot and qRT-PCR analysis. BMP10 levels were increased in the L4-6 ipsilateral spinal dorsal horn of SNI mice and particularly elevated in astrocytes. Consistently, GFAP and phosphorylated Smad1/5/8 were upregulated in the L4-6 ipsilateral spinal dorsal horn after SNI, indicating the activation of astrocytes and Smad1/5/8 signaling. An intrathecal injection of BMP10 siRNA abrogated pain hypersensitivity and astrocytic activation in SNI mice. In addition, intrathecal administration of BMP10 peptide evoked pain hypersensitivity and astrocytic activation in normal mice, and this action was reversed by inhibiting the ALK2. Furthermore, targeting Smad1 in vitro with the help of siRNA inhibited the activation of astrocytes induced by LPS. Finally, targeting Smad1 abrogated BMP10-induced hypersensitivity and activation of astrocytes. These findings indicate that the BMP10/ALK2/Smad1/5/8 axis plays a key role in pain hypersensitivity after peripheral nerve injury, which indicates its stimulative ability toward astrocytes.

Morphological classification of radial glia-like cells in the postnatal mouse subventricular zone.

The subventricular zone (SVZ) is one of the neurogenic regions of the adult mammalian brain. Neural stem cells (NSCs) in the SVZ have certain key features: they express glial fibrillary acidic protein (GFAP), proliferate slowly, have a radial glia-like (RG-L) morphology, and are in contact with the cerebrospinal fluid (CSF). NSCs have been isolated by FACS to analyse them, but their morphology has not been systematically examined. To address this knowledge gap, we sparsely labelled RG-L cells in the SVZ of neonatal mice by introducing via electroporation a plasmid expressing fluorescent protein under the control of the GFAP promoter. We then classified RG-L cells into three types (RG-L1, 2, and 3) based on their morphologies. RG-L1 cells had a basal process with some branches and numerous fine processes. RG-L2 cells had a basal process, but fewer branches and fine processes than RG-L1 cells. RG-L3 cells had one basal process that was almost free of branches and fine processes. Importantly, regardless of the cell type, about half of their somata resided on the basal side of the SVZ. Based on changes in their proportions during postnatal development and their expression of GFAP and cell proliferation markers at the adult stage, we speculated that NSCs change their morphologies during development/maturation and not all NSCs must always be in the apical SVZ or in contact with the CSF. Our results indicate that in addition to expression of markers for NSCs, the morphology is a critical feature to identify NSCs.

Microstructure of the dentate gyrus and spontaneous alternation behaviour of male Wistar rats following Rauvolfia vomitoria and Gongronema latifolium extracts administration

Rauvolfia vomitoria (RV) and Gongronema latifolium (GL) are medicinal plants used for the local treatment of various health issues. Their activities on the brain motivated this investigation on the histology and immunohistochemistry of the dentate gyrus and spontaneous alternation behaviour (SAB) of adult Wistar rats following RV root bark and GL leaf extract administrations. Twenty young adult Wistar rats (130–160 g) were assigned into four groups: Group 1 served as the control (5 mL/kg of distilled water placebo), while the test groups 2–4 were, respectively, singly administered 200 of mg/kg of RV, 200 of mg/kg of GL, and their combination. The administrations were oral and lasted for seven days. A T-maze SAB test was carried out, and the animals were sacrificed immediately after ketamine hydrochloride intraperitoneal anaesthesia. Serial sections of the hippocampal region from perfused rat brains were stained with Cresyl fast violet and immunolabelled with neuronal nuclei (NeuN) for neurons and glial fibrillary acidic protein (GFAP) for astrocytes. Results indicated that SAB was significantly (p &lt; 0.05) lower in the test groups. Histologically, Nissl was less distributed in the RV and GL-only groups but not in the combined group, while there was less NeuN positivity in the RV group, with the GL and RV + GL groups not affected. There was less positive GFAP expression in individual RV and GL groups, but not in the RV + GL combined group, all compared with the control. In conclusion, the combination of RV and GL did not improve SAB but modulated Nissl, NeuN, and GFAP expression in the dentate gyrus.

Hippocampal neurogenesis modulated by Quinic acid: A therapeutic strategy for the neurodegenerative disorders.

Neural progenitor cells (NPCs) reside in the brain and participate in the mechanism of neurogenesis that permits the brain to generate the building blocks for enhancement of cognitive abilities and acquisition of new skills. The existence of NPCs in brain has opened a novel dimension of research to explore their potential for treatment of various neurodegenerative disorders. The present study provides novel insights into the intracellular mechanisms in neuronal cells proliferation, maturation and differentiation regulated by Quinic acid (QA). Furthermore, this study might help in discovery and development of lead molecule that can overcome the challenges in the treatment of neurodegenerative diseases. The growth supporting effect of QA was studied using MTT assay. For that purpose, hippocampal cell cultures of neonatal rats were treated with different concentrations of QA and incubated for 24, 48 and 72 h. Gene and protein expressions of the selected molecular markers nestin, neuron-specific class III beta-tubulin (Tuj-1), neuronal nuclear protein (NeuN), neuronal differentiation 1 (NeuroD1), glial fibrillary acidic protein (GFAP), neuroligin (NLGN) and vimentin were analyzed. QA-induced cell proliferation and differentiation of hippocampal progenitor cells was also accompanied by significantly increased expression of progenitor and immature neuronal marker, mature neuronal marker and differentiating factor, that is, nestin, Tuj-1, NeuN and NeuroD1, respectively. On the other hand, vimentin downregulation and constant GFAP expression were observed following QA treatment. Additionally, the effects of QA on the recovery of stressed cells was studied using in vitro model of oxygen glucose deprivation (OGD). It was observed that hippocampal cells were able to recover from OGD following the treatment with QA. These findings suggest that QA treatment promotes hippocampal neurogenesis by proliferating and differentiating of NPCs and recovers neurons from stress caused by OGD. Thus, the neurogenic potential of QA can be explored for the treatment of neurodegenerative disorders.