To examine the effects of ischemia and anoxia on cell activation and cell cycle of astrocytes in vitro, the cell cycles and the proliferation of astrocytes in different time points after ischemia and anoxia were studied by flow cytometry and BrdU labeling and the expression of GFAP and cyclin D1 was detected by the fluorescence immunochemistry. After ischemia and anoxia in vitro, the astrocytes in S phase were significantly increased as compared with those in the normal group and the proliferating ability of the astrocytes was highest 6 h after the treatment as revealed by BrdU pulse labeling, but the astrocytes in S phase and proliferating ability were decreased after 6 h. At the early stages of ischemia and anoxia, the positive staining intensity of GFAP was increased, peaked at 6th h, while 12 h after the ischemia and anoxia, the positive staining intensity of GFAP became weak, and the expression of cyclin D1 was gradually increased after the ischemic and anoxic damage. It is concluded that astrocytes are activated to proliferate and enter new cycle events by ischemia and anoxia, and cyclin D1 is implicated in the proliferation and repair of astrocytes. The cell cycle events are closely associated with the proliferation and activation of astrocytes.
Animals, Newborn ; Astrocytes/*cytology ; Cell Cycle ; Cell Hypoxia ; Cell Proliferation ; Cells, Cultured ; Cyclin D1/biosynthesis ; Cyclin D1/genetics ; Glial Fibrillary Acidic Protein/*biosynthesis ; Glial Fibrillary Acidic Protein/genetics ; Rats, Wistar

Alexander disease (AD) is a rare leukodystrophy of the central nervous system of unknown etiology. AD is characterized by progressive failure of central myelination and the accumulation of Rosenthal fibers in astrocytes, and is inevitably lethal in nature. Symptomatically, AD is associated with leukoencephalopathy with macrocephaly, seizures, and psychomotor retardation in infants, and usually leads to death within the first decade. Its characteristic magnetic resonance imaging (MRI) findings have been described as demyelination predominantly in the frontal lobe. Moreover, dominant mutations in the GFAP gene, coding for glial fibrillary acidic protein (GFAP), a principal astrocytic intermediate filament protein, have been shown to lead to AD. The disease can now be detected by genetic diagnosis. We report the Korean case of an 8-month-old male patient with AD. He was clinically characterized due to the presence of psychomotor retardation, megalencephaly, spasticity, and recurrent seizures including infantile spasms which is a remarkable presentation. Demyelination in the frontal lobe and in a portion of the temporal lobe was demonstrated by brain MRI. Moreover, DNA analysis of peripheral blood showed the presence of a R239L mutation in the GFAP gene, involving the replacement of guanine with thymine.
Spasms, Infantile/*etiology ; *Mutation ; Male ; Magnetic Resonance Imaging ; Infant ; Humans ; Glial Fibrillary Acidic Protein/*genetics ; Electroencephalography ; Alexander Disease/complications/*diagnosis

OBJECTIVETo study the potential interaction between PrP protein and glial fibrillary acidic protein (GFAP) and identify the binding region within PrP with GFAP.

METHODSThe supernatant of healthy and scrapie-infected hamsters' brain homogenate was prepared, while various recombinant PrP or GFAP proteins were expressed using prokaryotic-expressing or in-vitro translation system. The possible molecular interaction between PrP proteins and GFAP was tested by Pull-down and immunoprecipitation assays.

RESULTSBoth native PrP(C) and its protease-resistant isoform (PrP(Sc)) formed complexes with the native GFAP. The full-length recombinant PrP proteins interacted with GFAP. The domain responsible for interacting GFAP was located at C-terminal of PrP (residues 91 to 231).

CONCLUSIONThe studies of the association of PrP with GFAP may further provide insight into a potential role of GFAP in the biological function of PrP and the pathogenesis of prion disease.

Animals ; Brain ; metabolism ; Cricetinae ; Gene Deletion ; Glial Fibrillary Acidic Protein ; genetics ; metabolism ; Immunoprecipitation ; Mice ; Prions ; genetics ; metabolism ; Protein Binding ; Recombinant Proteins ; metabolism

OBJECTIVETo study clinicopathologic features, treatment and prognosis of pilocytic astrocytoma (PA).

METHODSHistopathological, ultrastructural, immunohistochemical (EnVision method) and clinical features of 68 cases of PA were studied by microscopic investigation with correlation of clinical follow-up information when available.

RESULTSThirty-five male patients and 33 female patients were studied. The patient's age ranged from 3 to 66 years (mean = 20.1 years). The mean time from symptom onset to surgery was 371 days (range, 3 days to 14 years). Cystic degeneration was noted in 41 cases (60.3%), and enhancement of the tumor was noted in 43 cases (87.8%). On postcontrast imaging examination there were 33 cases involving the cerebellum (48.5%). Total tumor excision was performed in 35 patients, subtotal tumor excision was performed in 31 patients, and the procedures of other 2 patients were not clear. Among 51 patients with follow-up information, 44 were alive, 7 had recurrent tumor, and 7 died. The post-operative survival ranged from 2 months to 124 months (mean survival = 48.1 months). Five years and ten years survival rates were 89%, respectively. Tumors with classic histopathology demonstrated biphasic pattern of growth, consisting of compact elongated bipolar astrocytes associated with rosenthal fibers, and less cellular areas of multipolar cells with granular bodies and microcyst. Some cases showed atypia of nuclei, and occasional mitoses. Involvement of subarachnoid space was seen in 17 cases. One case had anaplastic features. All cases showed diffuse positive staining for GFAP and low expression for Ki-67, except 1 anaplastic tumor with 10% Ki-67 indices. Tumors with subarachnoid space involvement showed positive reticular fiber staining and negative EMA staining.

CONCLUSIONSPA is a benign, WHO grade I tumor with favorable prognosis, and does not require radiotherapy after total resection. The tumor can be mistaken as higher-grade astrocytoma when involving the subarachnoid space, and with cytological atypia, leading to unnecessary radiotherapy after surgery. Recurrence rate is increased when only partial resection is achieved. The outcome for patients with brainstem tumor or anaplastic PA is poor.

Astrocytoma ; diagnosis ; genetics ; Brain Neoplasms ; diagnosis ; genetics ; Cell Nucleus ; pathology ; Female ; Glial Fibrillary Acidic Protein ; genetics ; Humans ; Male ; Prognosis ; Recurrence ; Treatment Outcome

OBJECTIVETo study optical intrinsic signal (OIS) imaging of peri-infarct depolarizations (PIDs) in mice and investigate the influence of knockout of glial fibrillary acidic protein and vimentin on PIDs.

METHODSGFAP(⁺/⁺)Vim(⁺/⁺) mice and GFAP(⁺/⁺)Vim(⁺/⁺) mice were subjected to MCAO by standard intraluminal filament method. The main characteristics of PIDs in 4 h were studied by 4-wavelength OIS imaging technique.

RESULTSPIDs were identified as consistent, red and blue interaction waves in the cortical reflectance that slowly propagated peripherally from the origin site. There were 5 patterns of PID propagation, namely rostro-caudal, latero-medial, caudo-rostral, contralateral and medial-lateral. No significant differences were found in PID frequency, propagation patterns, velocity or duration time between the two groups (P>0.05).

CONCLUSIONThe 4-wavelength OIS system allows acquisition of high temporal-spatial resolution color images for analyzing temporal-spatial characteristics of PIDs in detail. Knockout of GFAP and vimentin do not affect PIDs in 4 h following middle cerebral artery occlusion.

Animals ; Glial Fibrillary Acidic Protein ; Infarction, Middle Cerebral Artery ; pathology ; Mice ; Mice, Knockout ; Nerve Tissue Proteins ; genetics ; Optical Imaging ; Vimentin ; genetics

OBJECTIVETo investigate the molecular basis of infantile Alexander disease in a Chinese patient, which may yield useful information for further genetic counseling.

METHODSDNA sequencing analysis and restriction endonuclease analysis were used to detect the mutation of glial fibrillary acidic protein (GFAP) gene in a patient with clinically diagnosed Alexander disease, in her parents and in 50 healthy controls.

RESULTSA 249C>T (R79C) mutation was identified in the exon 1 of the GFAP gene but not in her parents and the controls.

CONCLUSIONThe study on mutation of GFAP gene in Chinese patients with Alexander disease has never been reported previously. The mutation analysis of GFAP gene can provide valuable information for the diagnosis of Alexander disease and can serve as a reliable method of prenatal diagnosis for the family.

Alexander Disease ; diagnosis ; genetics ; Base Sequence ; Child, Preschool ; China ; DNA Mutational Analysis ; Female ; Genetic Predisposition to Disease ; Glial Fibrillary Acidic Protein ; genetics ; Humans ; Mutation ; Polymerase Chain Reaction

Animals ; Epilepsy ; genetics ; Gene Expression Regulation ; drug effects ; Glial Fibrillary Acidic Protein ; genetics ; metabolism ; Hippocampus ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Scorpion Venoms ; pharmacology

OBJECTIVETo investigate whether gliosis in the brain tissues of the hamsters infected with various amounts of scrapie strain 263K is correlated with the inoculation doses or the incubation times.

METHODSThe total values of glial fibrillary acidic protein (GFAP) in brains were evaluated by Western Blots and the GFAP-stained cells were detected by immunohistochemistry (IHC). The characteristics of GFAP distributions among various groups were defined by quantitive and statistic analyses.

RESULTSCompared with the brain tissues of normal hamsters, remarkably higher total GFAP levels and more GFAP-stained cells were observed in the brain tissues of infected ones, howbeit, no significant difference was addressed among the infected groups.

CONCLUSIONInoculations of various amounts of scrapie strain 263K into experimental hamsters intracerebrally induced the similar patterns of gliosis in the brains at the clinically terminal stage, regardless of infectious doses and incubation times.

Animals ; Brain ; metabolism ; pathology ; Cricetinae ; Gene Expression ; Glial Fibrillary Acidic Protein ; genetics ; metabolism ; Gliosis ; metabolism ; pathology ; Humans ; PrPSc Proteins ; metabolism ; Prion Diseases ; metabolism ; pathology

Alzheimer Disease ; pathology ; China ; Genes, p53 ; Glial Fibrillary Acidic Protein ; metabolism ; Humans ; Multiple Sclerosis ; pathology ; Nervous System Neoplasms ; classification ; genetics ; metabolism ; pathology

BACKGROUNDMüller cells in the mammalian retina normally express low levels of glial fibrillary acidic protein (GFAP); however, its expression is upregulated in response to the loss of retinal neurons. The change in expression of GFAP is one of the earliest indicators of retinal damage and is correlated with the time course of disease. The aim of this study was to investigate the time course of degeneration and the expression of GFAP in the retina of mer knockout mice.

METHODSA total of 30 mer knockout mice, aged from 15 - 20 days to 1 year and 32 age-matched wild type mice as controls were tested. Immunohistochemistry was used to show the expression of GFAP in the central and peripheral retina of mer knockout and control mice at postnatal age of 15 days (P15d), 20 days (P20d), 4 weeks (P4w), 6 weeks (P6w), 8 weeks (P8w), 3 months (P3m), 6 months (P6m) and 1 years (P1y).

RESULTSThe expression of GFAP in the central and peripheral retina of wild type mice was limited to the retinal ganglion cell and nerve fiber layers. In the central retina of mer knockout mice, GFAP expression was upregulated at P4w and GFAP immunolabelling penetrates across the entire thickness of the retina at P8w; whereas in the peripheral retina, the GFAP expression was upregulated at P20d and GFAP immunolabelling penetrates the entire retina after P4w.

CONCLUSIONSIncreased expression of GFAP in Müller cells of mer knockout mice occur at P20d in the peripheral retina and P4w in the central retina. GFAP expression in Müller cells appears to be a secondary response to the loss of retinal neurons. Increased expression of GFAP may occur prior to any detectable morphological changes in the retina. This study suggests that the loss of retinal neurons may begin in the early stages of retinitis pigmentosa, prior to the discovery of any morphological changes in the retina.

Animals ; Glial Fibrillary Acidic Protein ; metabolism ; Immunohistochemistry ; Mice ; Mice, Knockout ; Proto-Oncogene Proteins ; genetics ; Receptor Protein-Tyrosine Kinases ; genetics ; Retina ; metabolism ; pathology ; Retinitis Pigmentosa ; genetics ; metabolism ; c-Mer Tyrosine Kinase