Neurological diseases are a major health concern, and brain injury is a typical pathological process in various neurological disorders. Different biomarkers in the blood or the cerebrospinal fluid are associated with specific physiological and pathological processes. They are vital in identifying, diagnosing, and treating brain injuries. In this review, we described biomarkers for neuronal cell body injury (neuron-specific enolase, ubiquitin C-terminal hydrolase-L1, αII-spectrin), axonal injury (neurofilament proteins, tau), astrocyte injury (S100β, glial fibrillary acidic protein), demyelination (myelin basic protein), autoantibodies, and other emerging biomarkers (extracellular vesicles, microRNAs). We aimed to summarize the applications of these biomarkers and their related interests and limits in the diagnosis and prognosis for neurological diseases, including traumatic brain injury, status epilepticus, stroke, Alzheimer's disease, and infection. In addition, a reasonable outlook for brain injury biomarkers as ideal detection tools for neurological diseases is presented.
Humans ; Biomarkers/cerebrospinal fluid* ; Nervous System Diseases/diagnosis* ; Brain Injuries/metabolism* ; Phosphopyruvate Hydratase/cerebrospinal fluid* ; Glial Fibrillary Acidic Protein/blood* ; S100 Calcium Binding Protein beta Subunit/blood* ; tau Proteins/cerebrospinal fluid* ; Ubiquitin Thiolesterase/blood* ; Myelin Basic Protein/cerebrospinal fluid* ; Neurofilament Proteins/blood* ; MicroRNAs/blood* ; Brain Injuries, Traumatic/metabolism*

OBJECTIVE: To investigate the effects of removing microglia from spinal cord on nerve repair and functional recovery after spinal cord injury (SCI) in mice. METHODS: Thirty-nine 6-week-old female C57BL/6 mice were randomly divided into control group ( n=12), SCI group ( n=12), and PLX3397+SCI group ( n=15). The PLX3397+SCI group received continuous feeding of PLX3397, a colony-stimulating factor 1 receptor inhibitor, while the other two groups were fed a standard diet. After 14 days, both the SCI group and the PLX3397+SCI group were tested for ionized calcium binding adapter molecule 1 (Iba1) to confirm that the PLX3397+SCI group had completely depleted the spinal cord microglia. The SCI model was then prepared by clamping the spinal cord in both the SCI group and the PLX3397+SCI group, while the control group underwent laminectomy. Preoperatively and at 1, 3, 7, 14, 21, and 28 days postoperatively, the Basso Mouse Scale (BMS) was used to assess the hind limb function of mice in each group. At 28 days, a footprint test was conducted to observe the gait of the mice. After SCI, spinal cord tissue from the injury site was taken, and Iba1 immunofluorescence staining was performed at 7 days to observe the aggregation and proliferation of microglia in the spinal cord. HE staining was used to observe the formation of glial scars at the injury site at 28 days; glial fibrillary acidic protein (GFAP) immunofluorescence staining was applied to astrocytes to assess the extent of the injured area; neuronal nuclei antigen (NeuN) immunofluorescence staining was used to evaluate neuronal survival. And 5-hydroxytryptamine (5-HT) immunofluorescence staining was performed to assess axonal survival at 60 days. RESULTS: All mice survived until the end of the experiment. Immunofluorescence staining revealed that the microglia in the spinal cord of the PLX3397+SCI group decreased by more than 95% compared to the control group after 14 days of continuous feeding with PLX3397 ( P<0.05). Compared to the control group, the BMS scores in the PLX3397+SCI group and the SCI group significantly decreased at different time points after SCI ( P<0.05). Moreover, the PLX3397+SCI group showed a further decrease in BMS scores compared to the SCI group, and exhibited a dragging gait. The differences between the two groups were significant at 14, 21, and 28 days ( P<0.05). HE staining at 28 days revealed that the SCI group had formed a well-defined and dense gliotic scar, while the PLX3397+SCI group also developed a gliotic scar, but with a more blurred and loose boundary. Immunofluorescence staining revealed that the number of microglia near the injury center at 7 days increased in the SCI group than in the control group, but the difference between groups was not significant ( P>0.05). In contrast, the PLX3397+SCI group showed a significant reduction in microglia compared to both the control and SCI groups ( P<0.05). At 28 days after SCI, the area of spinal cord injury in the PLX3397+SCI group was significantly larger than that in SCI group ( P<0.05); the surviving neurons significantly reduced compared with the control group and SCI group ( P<0.05). The axonal necrosis and retraction at 60 days after SCI were more obvious. CONCLUSION The removal of microglia in the spinal cord aggravate the tissue damage after SCI and affecte the recovery of motor function in mice, suggesting that microglia played a neuroprotective role in SCI.
Animals ; Spinal Cord Injuries/surgery* ; Microglia/pathology* ; Female ; Mice ; Mice, Inbred C57BL ; Nerve Regeneration/drug effects* ; Spinal Cord/pathology* ; Pyrroles/administration & dosage* ; Aminopyridines/administration & dosage* ; Recovery of Function ; Disease Models, Animal ; Calcium-Binding Proteins/metabolism* ; Receptors, Granulocyte-Macrophage Colony-Stimulating Factor/antagonists & inhibitors* ; Microfilament Proteins/metabolism* ; Glial Fibrillary Acidic Protein/metabolism*

OBJECTIVES: To study the clinical features of children with autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A). METHODS: A retrospective analysis was performed on the medical data of 34 children with GFAP-A who attended the Department of Neurology, Children's Hospital of Chongqing Medical University, from January 2020 to February 2022. The medical data included clinical manifestations, cerebrospinal fluid features, imaging examination results, treatment, and prognosis. RESULTS: The median age of onset was 8.4 (range 1.9-14.9) years for the 34 children with GFAP-A. The main clinical manifestations included headache (50%, 17/34), fever (47%, 16/34), visual impairment (47%, 16/34), and disturbance of consciousness (44%, 15/34). Abnormal cerebrospinal fluid results were observed in 19 children (56%, 19/34), among whom 8 children had positive autoantibody. The children with overlap syndrome had significantly higher recurrence rate and rate of use of immunosuppressant than those without overlap syndrome (P<0.05). About 77% (24/31) of the children had good response to immunotherapy, and only 1 child had poor prognosis. CONCLUSIONS Children with GFAP-A often have non-specific clinical symptoms and show good response to immunotherapy. Children with overlap syndrome have a high recurrence rate, and early application of immunosuppressants may help to prevent recurrence and alleviate symptoms.
Adolescent ; Child ; Child, Preschool ; Humans ; Infant ; Astrocytes/metabolism* ; Autoantibodies/metabolism* ; Glial Fibrillary Acidic Protein/metabolism* ; Prognosis ; Retrospective Studies ; Autoimmune Diseases/metabolism*

Objective: Antimony (Sb) has recently been identified as a novel nerve poison, although the cellular and molecular mechanisms underlying its neurotoxicity remain unclear. This study aimed to assess the effects of the nuclear factor kappa B (NF-κB) signaling pathway on antimony-induced astrocyte activation. Methods: Protein expression levels were detected by Western blotting. Immunofluorescence, cytoplasmic and nuclear fractions separation were used to assess the distribution of p65. The expression of protein in brain tissue sections was detected by immunohistochemistry. The levels of mRNAs were detected by Quantitative real-time polymerase chain reaction (qRT-PCR) and reverse transcription-polymerase chain reaction (RT-PCR). Results: Antimony exposure triggered astrocyte proliferation and increased the expression of two critical protein markers of reactive astrogliosis, inducible nitric oxide synthase (iNOS) and glial fibrillary acidic protein (GFAP), indicating that antimony induced astrocyte activation Conclusion Antimony activated astrocytes by activating the NF-κB signaling pathway.
Animals ; Antimony/toxicity* ; Astrocytes/metabolism* ; Cell Line, Tumor ; Cell Proliferation/drug effects* ; Glial Fibrillary Acidic Protein/metabolism* ; MAP Kinase Kinase Kinases ; Male ; Mice, Inbred ICR ; NF-kappa B/metabolism* ; Nitric Oxide Synthase Type II/metabolism* ; Rats ; Signal Transduction/drug effects*

OBJECTIVE: To observe the effects of on the expression of β-tubulin Ⅲ and glial fibrillary acidic protein (GFAP) and the proliferation and differentiation of murine neural stem cells (NSCs) . METHODS: An immortalized murine NSC line was divided into model control (MC) group, 10% drug-containing serum group (NLXT group), and 10% Naoluoxintong drug-containing serum with inhibitor Y27632 group (Y-27632 group) with corresponding treatments. The activity of the NSCs was detected after the treatments using MTT assay, and the migration of the cells was observed with Transwell assay. The expressions of β-tubulin Ⅲ, GFAP and MAP-2 proteins in the cells were detected with immunoblotting, and the expressions of DCX, NEUN, and β-tubulin Ⅲ were also detected with immunofluorescence assay. RESULTS: Compared with that in MC group, the number of migrated cells in NLXT group and Y-27632 group increased significantly at 1 day and 3 days after induction ( < 0.05). The survival rate and the number of migrated cells in NLXT group and Y-27632 group increased significantly on day 7 ( < 0.01). Compared with those in MC group, the expressions of β-tubulin Ⅲ, MAP2 and GFAP protein in NLXT group and Y-27632 group were significantly increased on days 3 ( < 0.01) and 7 ( < 0.05). The numbers of β-tubulinⅢ/ GFAP, BrdU/DCX, and BrdU/NEUN labeled cells in the NLXT group and Y-27632 group were significantly greater than those in the MC group. CONCLUSIONS promotes the proliferation and differentiation of murine NSCs by regulating the expressions of β-tubulinⅢ/GFAP.
Animals ; Cell Differentiation ; Cell Proliferation ; Glial Fibrillary Acidic Protein ; Mice ; Neural Stem Cells ; Tubulin

To explore the effects of intrauterine infection on early growth and neurobehavioral development in neonatal rats. (E. coli) was inoculated into uterine cervix of pregnant rats with gestation of 15 d to establish the intrauterine infection model, and the effect on the delivery of pregnant rats was observed. The neonatal rat brain tissue was stained with Hematoxylin-Eosin and the cerebral white matter damage was assessed. Immunohistochemical staining and Western blot analysis were performed to evaluate the expression of glial fibrillary acidic protein (GFAP), 2', 3'-cyclic nucleotide 3'-phosphodiesterase (CNPase) and neurofilament (NF) in pup brains. Birth weight and early growth development indices were monitored,and neurobehavioral tests were performed to access the change of neurobehavioral development in neonatal rats. The white blood cell count increased significantly in the uterus and placenta of the pregnant rats after intrauterine E. coli infection and no significant impact was observed on the delivery of pregnant rats. Weak staining and focal rarefaction of cerebral white matter from rats at P7 in intrauterine infection group were observed. The expression of GFAP markedly increased (<0.05) in infection group, while the level of CNPase and NF in pup brains at P7 significantly decreased (<0.05 or <0.01). Compared with control group, the neonatal rats in infection group had lower birth weight and slower weight gain during the suckling period (<0.05 or <0.01), and the completion times of ear opening, eye opening, surface righting, negative geotaxis, acoustic startle and swimming test in infection group were significantly delayed (<0.05 or <0.01). Intrauterine infection in pregnant rats can induce cerebral white matter damage and retardation of early growth and neurobehavioral development in neonatal rats.
Animals ; Animals, Newborn ; Behavior, Animal ; Body Weight ; Disease Models, Animal ; Escherichia coli ; Escherichia coli Infections ; complications ; physiopathology ; Female ; Glial Fibrillary Acidic Protein ; genetics ; Growth Disorders ; etiology ; Leukoencephalopathies ; etiology ; Pregnancy ; Pregnancy Complications, Infectious ; physiopathology ; Rats ; Rats, Sprague-Dawley

To compare the biological functions of astrocytes cultured by two methods. Methods The primary astrocytes were cultured from rodent neonatal brain,whereas the differentiated astrocytes were prepared by differentiating neural stem cells with fetal bovine serum.The morphologies of these two different types of astrocytes were observed under microscope and the expression of glial fibrillary acidic protein(GFAP),an astrocyte-specific marker,was detected by immunofluorescence staining after treatment with 10 cytokines.Changes in GFAP,glutamate synthetase(GS),glutamate-aspartic acid transporter(xCT),neuregulin-1(NRG),N-methyl-D-aspartic acid receptor(NMDA),lipoprotein lipase(LPL)were detected and compared. Results The morphologies and GFAP expression differed between these two astrocyte types.Microarray showed that the expressions of GFAP,GS,xCT,NRG,NMDA,and LPL were significantly higher in primary astrocytes than in differentiated astrocytes.None of these 10 cytokines increased the expression of GFAP in primary astrocytes,whereas treatment with transforming growth factor-β(TGF-β)significantly increased the expression of GFAP in the differentiated astrocytes. Conclusion Compared with the differentiated astrocytes,the primary astrocytes are more similar to reactive astrocytes,and TGF-β can promote the transition of differentiated cells to reactive cells.
Animals ; Animals, Newborn ; Astrocytes ; cytology ; Cell Differentiation ; Cells, Cultured ; Glial Fibrillary Acidic Protein ; metabolism ; Neural Stem Cells ; cytology ; Rodentia ; Transforming Growth Factor beta ; pharmacology

OBJECTIVE: Spinal cord injury (SCI) is a very serious health problem, usually caused by a trauma and accompanied by elevated levels of inflammation indicators. Stem cell-based therapy is promising some valuable strategies for its functional recovery. Nestin-positive progenitor and/or stem cells (SC) isolated from pancreatic islets (PI) show mesenchymal stem cell (MSC) characteristics. For this reason, we aimed to analyze the effects of rat pancreatic islet derived stem cell (rPI-SC) delivery on functional recovery, as well as the levels of inflammation factors following SCI.METHODS: rPI-SCs were isolated, cultured and their MSC characteristics were determined through flow cytometry and immunofluorescence analysis. The experimental rat population was divided into three groups : 1) laminectomy & trauma, 2) laminectomy & trauma & phosphate-buffered saline (PBS), and 3) laminectomy+trauma+SCs. Green fluorescent protein (GFP) labelled rPI-SCs were transplanted into the injured rat spinal cord. Their motilities were evaluated with Basso, Beattie and Bresnahan (BBB) Score. After 4-weeks, spinal cord sections were analyzed for GFP labeled SCs and stained for vimentin, S100β, brain derived neurotrophic factor (BDNF), 2’,3’-cyclic-nucleotide 3'-phosphodiesterase (CNPase), vascular endothelial growth factor (VEGF) and proinflammatory (interleukin [IL]-6, transforming growth factor [TGF]-β, macrophage inflammatory protein [MIP]-2, myeloperoxidase [MPO]) and anti-inflammatory (IL-1 receptor antagonis) factors.RESULTS: rPI-SCs were revealed to display MSC characteristics and express neural and glial cell markers including BDNF, glial fibrillary acidic protein (GFAP), fibronectin, microtubule associated protein-2a,b (MAP2a,b), β3-tubulin and nestin as well as antiinflammatory prostaglandin E2 receptor, EP3. The BBB scores showed significant motor recovery in group 3. GFP-labelled cells were localized on the injury site. In addition, decreased proinflammatory factor levels and increased intensity of anti-inflammatory factors were determined.CONCLUSION: Transplantation of PI-SCs might be an effective strategy to improve functional recovery following spinal cord trauma.
Animals ; Brain-Derived Neurotrophic Factor ; Dinoprostone ; Fibronectins ; Flow Cytometry ; Fluorescent Antibody Technique ; Glial Fibrillary Acidic Protein ; Inflammation ; Islets of Langerhans ; Laminectomy ; Macrophages ; Mesenchymal Stromal Cells ; Microtubules ; Nestin ; Neuroglia ; Peroxidase ; Rats ; Regeneration ; Spinal Cord Injuries ; Spinal Cord ; Stem Cell Transplantation ; Stem Cells ; Transforming Growth Factors ; Vascular Endothelial Growth Factor A ; Vimentin ; Wounds and Injuries

Objective To observe the expression changes of nuclear factor-erythroid derived 2-related factors （Nrf2） in different cells at different time points after human cerebral cortex contusion, and to discuss its application in brain wound age estimation. Methods Thirty-six human brain tissues were selected, of which 6 were for control and 30 were cortical contusion at different time points post-injury, which were divided into 0-1 h, 3-6 h, 1-3 d, 5-7 d, and 10-14 d post-injury groups, with 6 cases in each group. Based on paraffin embedded sections, HE staining was used to observe the morphological changes post-injury, and double immunofluorescence staining was used to detect the expression of Nrf2 in neurons, astrocytes, and microglia. The number of positive cells was counted and statistical analysis was made. Results The number of neurons decreased 1-3 d post-injury. The expression of Nrf2 cells in neurons increased after injury, and the rate of positive cells peaked at 1-3 d post-injury. Glial cells were activated 1-3 d post-injury, and the activation peaked at 5-7 d post-injury. The cerebromalacia began to form at 10-14 d post-injury. Glial fibrillary acidic protein （GFAP） positive cells in mice increased gradually after injury and peaked at 5-7 d post-injury, while the proportion of Nrf2 in GFAP positive cells was relatively stable. After injury, ionized calcium-binding adapter molecule 1 （IBA1） positive cells increased and activated gradually. The expression proportion of Nrf2 in IBA1 positive cells increased gradually, reached its peak at 5-7 d post-injury, and then decreased. Conclusion The expression of Nrf2 in different cells involves in the biological function of different cells post-injury, and the dynamic expression of single cells has a time-dependent pattern. This may provide a new reference index for the wound age estimation of brain contusion in human.
Animals ; Brain Contusion ; Cerebral Cortex ; Glial Fibrillary Acidic Protein ; Humans ; Mice ; NF-E2-Related Factor 2

To determine expression levels of glial fibrillary acidic protein in patients of sepsis-associated encephalopathy (SAE) and its clinical significance.
 Methods: Patients, admitted to intensive care units and diagnosed as sepsis, were recruited to our study from October 2016 to August 2018 in the Third Xiangya Hospital, Central South University. SAE is defined as a brain dysfunction secondary to sepsis and without evidence of a primary central nervous system infection or encephalopathy due to other reasons. The SAE group and non-SAE group were classed by Confusion Assessment Method for the ICU (CAM-ICU) score. We measured the levels of serum GFAP, S100β and neuron-specific enolase (NSE) within 24 hours after diagnosis of sepsis, and compared the patients' general clinical data, ICU stay time, 28-day and 180-day mortality.
 Results: Among 152 enrolled patients, 58 and 94 were assigned to the SAE group and the non-SAE group, respectively. There were a significantly higher Sequential Organ Failure Assessment (SOFA) scores, 28-day mortality rate, as well as 180-day mortality rate in the SAE group (all P<0.001). The levels of GFAP, NSE and S100β in the SAE group were significantly higher than those in the non-SAE group (all P<0.001). The diagnostic values of GFAP was 0.67 μg/L, with sensitivity at 75.9% and specificity at 77.7%. Area under the receiver operating characteristic curve (AUROC) of GFAP, NSE and S100β were 0.803, 0.795 and 0.750, respectively. Pearson analysis showed that serum GFAP level was positively correlated with Acute Physiology and Chronic Health Evaluation II (APACHE II) score, but it was negatively correlated with Glasgow Coma Scale (GCS) score, 28-day survival rate and 180-day survival rate.
 Conclusion: The level of serum GFAP is significantly increased in SAE, which shows certain correlation with incidence, severity and prognosis of the disease.
APACHE ; Glial Fibrillary Acidic Protein ; blood ; Humans ; Intensive Care Units ; Organ Dysfunction Scores ; Prognosis ; ROC Curve ; Sepsis ; Sepsis-Associated Encephalopathy ; diagnosis