OBJECTIVETo investigate whether fenvalerate can induce mouse hippocampal nerve cell damage by interfering with estrogen (E2) effect.

METHODSHippocampus were dissected and cultured from Embryo 18 d ICR mice, the cells were cultured for 7 days. Fenvalerate (FEN, 0, 1, 10, 50 µg/ml), FEN (10, 50 µg/ml) and estrogen receptor antagonist ICI 182, 780 (1 µmol/L), FEN (0, 10, 50 µg/ml) and E2 (10 nmol/L) were applied to the cultured cells for 48h. Immunocytochemically stained with neurons and astrocytes to evaluate the levels respectively, and the growth of neurite. Result 1µg/ml FEN have no effect on neurons, neurites and protoplasmic astrocytes, 10 and 50 µg/ml FEN can significantly decrease the neuron viability and the length of neurite as well as increase the level of protoplasmic astrocytes (P < 0.05 vs. control group). ICI 182, 780 alone have no effect on neurons, neurites and protoplasmic astrocytes; ICI+10 µg/ml FEN significantly increase the cell viability and extend neurite length as well as decrease protoplasmic astrocytes (P < 0.05 vs. 10 µg/ml FEN alone group); ICI+50 µg/ml FEN significantly increase the cell viability and decrease protoplasmic astrocytes (P < 0.05 vs. 50 µg/ml FEN alone group). E2 alone have no effect on protoplasmic astrocytes, while can promote neuronal survival and neurite growth; E2+10 µg/ml FEN and E2+50 µg/ml FEN significantly decrease neuronal survival and neurite growth, as well as increase protoplasmic astrocytes (P < 0.05 vs. E2 alone group).

CONCLUSIONFenvalerate can induce the loss of hippocampal neurons through disrupting estrogen nuclear receptor signaling, and inhibit the length of neurite through disrupting estrogen nuclear receptor and membrane receptor signaling. The effect of estrogen disruption play an important role in developmental neurotoxicity by fenvalerate.

Animals ; Astrocytes ; drug effects ; Cells, Cultured ; Estrogens ; pharmacology ; Hippocampus ; drug effects ; pathology ; Mice ; Mice, Inbred ICR ; Neurons ; drug effects ; pathology ; Nitriles ; toxicity ; Pyrethrins ; toxicity

To investigate the neutralizing effect of N-acetylcysteine (NAC) and selenium (Se) aganist doxorubicin (DOX) toxicity in rats, NAC (140 mg/kg, p.o.) and Se (0.5 mg/kg, p.o.) were administered for 2 days before DOX injection and then 3 times a week. Cell viability and the level of lipid peroxidation were examined in cultured-rat astrocytes. Severe morphologic changes in the kidney of DOX group; thickening of Bowmans capsule, presence of multifocal tubular casts were observed, but not in the other treated groups. Vacuoles in some hepatic cells and focal aggregation of stellate macrophages were also detected in DOX group, but not in the other treated groups. However, the severe inhibition of spermatogenesis was found in all treated groups. The cell viability of DOX (10 mg/ml) treated group and NAC (5 mM) or Se (0.001 mg/ml) combinedtreated group was 52.5+/-2.0 % , 85.3+/-4.5 % and 75.5+/-1.6 %, respectively. In MDA (malondialdehyde) assay, the level of lipid peroxidation on DOX (10 mg/ml), NAC (5 mM) and Se (0.001 mg/ml) was 0.77+/-0.06, 0.35+/-0.06 and 0.54+/-0.11 nmol/mg protein, respectively. Thus, it is known that NAC and Se have protective effects in kidney and liver but not in the testes. Morphological change was not detected in brain and heart in all groups for experiment period. From this in vitro study, it is known that NAC and Se protect well the astrocytes against DOX induced-cell damage.
Acetylcysteine/*pharmacology ; Animals ; Astrocytes/*cytology/drug effects/pathology ; Cell Survival/drug effects ; Cells, Cultured ; Doxorubicin/antagonists & inhibitors/*toxicity ; Liver/cytology/*drug effects/pathology ; Male ; Rats ; Rats, Sprague-Dawley ; Spermatocytes/cytology/drug effects/pathology

Epidemiological studies have suggested an association between pesticide exposure and Parkinson's disease. In this study, we examined the neurotoxicity of an organochlorine pesticide, heptachlor, in vitro and in vivo. In cultured SH-SY5Y cells, heptachlor induced mitochondria-mediated apoptosis. When injected into mice intraperitoneally on a subchronic schedule, heptachlor induced selective loss of dopaminergic neurons in the substantia nigra pars compacta. In addition, the heptachlor injection induced gliosis of microglia and astrocytes selectively in the ventral midbrain area. When the general locomotor activities were monitored by open field test, the heptachlor injection did not induce any gross motor dysfunction. However, the compound induced Parkinsonism-like movement deficits when assessed by a gait and a pole test. These results suggest that heptachlor can induce Parkinson's disease-related neurotoxicities in vivo.
Animals ; *Apoptosis ; Astrocytes/drug effects/pathology ; Cell Line, Tumor ; Cells, Cultured ; Dopaminergic Neurons/*drug effects/pathology ; Gait ; Heptachlor/*toxicity ; Humans ; *Locomotion ; Mice ; Neurotoxicity Syndromes/etiology/physiopathology ; Parkinsonian Disorders/chemically induced ; Pesticides/*toxicity ; Substantia Nigra/*drug effects/pathology/physiopathology

To study the relationship between tau hyperphosphorylation and the function of glutamate transporter okadaic acid (OA), a protein phosphatase inhibitor, 20 ng in a 0.5 microl volume, was injected into the frontal cortex of rat brain and immunostaining was used to observe the phosphorylation of tau protein and the expression of excitatory amino acid transporter 1 (EAAT1) in the brain following the injection. The results showed that (1) the neurons in the center of the injection region displayed cytoplasmic shrinkage, swelling, nuclear pyknosis, and dislocation at the early stage, and necrosis appeared 3 d after the injection. However, most neurons in the peri-injected areas showed normal morphological characters with immuno positive reaction for AT8, a tau phosphorylated marker; (2) morphological analysis showed that tau hyperphosphorylation caused by OA treatment was mainly observed in the axons and dendrites of neuronal cells at 6 h in the cell body at 1 d, which brought about dystrophic neurites and neurofibrillary tangle (NFT)-like pathological changes; (3) the induction of glutamate transporter EAAT1 was observed in the involved areas corresponding to that with AT8 immunopositive staining, and the number of EAAT1-positive staining cells markedly increased at 12 h (P<0.01), peaked at 1 d (P<0.001), then decreased at 3 d following the injection. Combined with a confocal laser scanning microscopic analysis, double fluorescent immunostaining showed that EAAT1 positive staining appeared in neurons as well as astrocytes in the peri-injected areas of the frontal cortex. These results demonstrate that OA increases glutamate transporter EAAT1 expression in neurons while it induces tau hyperphosphorylation. However, the mechanism and significance of the induction of glutamate transporter EAAT1 expression remain to be further elucidated.
Animals ; Astrocytes ; drug effects ; metabolism ; Axons ; drug effects ; metabolism ; Brain ; cytology ; Dendrites ; drug effects ; metabolism ; Excitatory Amino Acid Transporter 1 ; metabolism ; Neurofibrillary Tangles ; pathology ; Neurons ; drug effects ; metabolism ; Okadaic Acid ; pharmacology ; Phosphorylation ; Rats ; tau Proteins ; metabolism

OBJECTIVETo investigate the apoptosis rules of the astrocytes and oligodendrocytes induced by Ca(2+) reperfusion.

METHODSThe apoptosis of purified cultured astrocytes and oligodendrocytes induced by Ca(2+) reperfusion and the relationship between the development of the cell apoptosis and post-reperfusion time was observed.

RESULTSBoth the astrocytes and oligodendrocytes were obviously in a time-dependent fashion, and the apoptosis ratios of the oligodendrocytes (39.73%+/-4.16%) were higher than the astrocytes (19.64%+/-4.67%) 24 hours after Ca(2+) reperfusion. The TUNEL positive cells were 13.6+/-1.82 and 21.4+/-1.95 at every visual field of astrocytes and oligodendrocytes respectively 24 hours after Ca(2+) reperfusion.

CONCLUSIONSThe astrocytes and oligodendrocytes are similar wi th the development rules on apoptosis and have different susceptiveness to the situation.

Animals ; Apoptosis ; drug effects ; physiology ; Astrocytes ; cytology ; pathology ; physiology ; Calcium ; physiology ; Cells, Cultured ; Flow Cytometry ; In Situ Nick-End Labeling ; Oligodendroglia ; cytology ; pathology ; physiology ; Rats ; Rats, Wistar

Hydrogen peroxide is considered to be a dose- and time-dependent mediator in apoptotic and necrotic death. In this study, we examined the signaling of the E6 and E7 proteins with respect to apoptosis or necrosis after H2O2 injury using an in vitro model with overexpressed E6 or E7 genes. For this purpose, the E6 and E7 gene expressing astrocytes were exposed to 0.01 mM and 0.2 mM H2 O2 solutions. Twenty- four hours after treatment with the lower dosage(0.01 mM H2O2), control, E6-expressing cells suffered about 45% injury and LXSN-expressi ng cells decreased by 67% as assessed by LDH release. However, E7-expressing cells showed less injury, resulting in 20-30% of LDH release. Astrocytes expressing E6, E7, LXSN and mock-infected cells showed a typical apoptotic death patter n on the DNA gel after treatment with a low-dose of H2O2 (0.01 mM), however the y died from necrotic death after a high-dose (0.2 mM) H2O2. Overexpression of HPV-E7 genes protected the cells from apoptotic death after a low-dose of H2O2 and from necrotic death after a high-dose of H2O2, while the overexpression of E 6 genes from the necrotic death. E7 expressing astrocytes showed higher catalas e activity and the levels of E2F protein surged more than 100-folds compared with the control astrocytes. We believe that the activity of E7 protein to protect astrocytes from H2O2 injury was at least partly due to increased catalase, a scavenger protein.
Animal ; Apoptosis/*physiology ; Astrocytes/*drug effects/pathology/*physiology ; Cells, Cultured ; Hydrogen Peroxide/*pharmacology ; Mice ; Necrosis ; Oncogene Proteins, Viral/*genetics/*physiology ; Oxidants/*pharmacology ; Signal Transduction/physiology

OBJECTIVE: To explore the effect of hepatocyte growth factor (HGF) on oxygen-glucose deprived injury and apoptosis of astrocytes. METHODS: The injury of primary cultured rat cerebral cortical astrocytes was induced by oxygen-glucose deprivation. Astrocytes were treated with HGF at various final concentrations of 20 - 100 ng/mL. The cell damage and viability were evaluated by the lactate dehydrogenase (LDH) released rate and the 3- (4,5-dimethylthazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) conversion method. Detection of apoptotic cells was determined by the flow cytometry, and the ultrastructure was observed by the transmission electron microscope. RESULTS: Oxygen-glucose deprivation increased the LDH release rate, decreased the cell viability and increased the number of apoptotic astrocytes. While exposed to HGF at the same condition, the LDH release rate decreased, the cell viability increased, and the percentage of apoptotic cells decreased (P <0.05). The maximum protective effect of HGF was observed at 60 ng/mL. CONCLUSION HGF can protect cultured astrocytes from oxygen-glucose deprived injury, and attenuate the apoptosis of astrocytes in a dose-dependent manner.
Animals ; Apoptosis ; drug effects ; Astrocytes ; pathology ; Cell Hypoxia ; Glucose ; pharmacology ; Hepatocyte Growth Factor ; pharmacology ; Rats ; Rats, Sprague-Dawley ; Reperfusion Injury ; metabolism

As one of trials on neuroprotection after spinal cord injury, we used pregabalin. After spinal cord injury (SCI) in rats using contusion model, we observed the effect of pregabalin compared to that of the control and the methylprednisolone treated rats. We observed locomotor improvement of paralyzed hindlimb and body weight changes for clinical evaluation and caspase-3, bcl-2, and p38 MAPK expressions using western blotting. On histopathological analysis, we also evaluated reactive proliferation of glial cells. We were able to observe pregabalin's effectiveness as a neuroprotector after SCI in terms of the clinical indicators and the laboratory findings. The caspase-3 and phosphorylated p38 MAPK expressions of the pregabalin group were lower than those of the control group (statistically significant with caspase-3). Bcl-2 showed no significant difference between the control group and the treated groups. On the histopathological analysis, pregabalin treatment demonstrated less proliferation of the microglia and astrocytes. With this animal study, we were able to demonstrate reproducible results of pregabalin's neuroprotection effect. Diminished production of caspase-3 and phosphorylated p38 MAPK and as well as decreased proliferation of astrocytes were seen with the administration of pregabalin. This influence on spinal cord injury might be a possible approach for achieving neuroprotection following central nervous system trauma including spinal cord injury.
Animals ; Apoptosis/drug effects ; Astrocytes/drug effects/pathology ; Blotting, Western ; Body Weight/drug effects ; Caspase 3/genetics ; Cell Proliferation ; Fluorescent Antibody Technique ; Gene Expression ; Hindlimb/drug effects/pathology/physiopathology ; Inflammation ; Male ; Methylprednisolone/therapeutic use ; Microglia/drug effects/pathology ; Motor Activity/drug effects ; Neuroglia/*drug effects/pathology ; Neuroprotective Agents/*therapeutic use ; Paralysis/drug therapy ; Proto-Oncogene Proteins c-bcl-2/genetics ; Rats ; Rats, Sprague-Dawley ; Spinal Cord Injuries/*drug therapy/pathology ; gamma-Aminobutyric Acid/*analogs & derivatives/therapeutic use ; p38 Mitogen-Activated Protein Kinases/genetics

Metallothionein (MT) is a kind of metal binding protein. As an important member in metallothionein family, MT-I/II regulates metabolism and detoxication of brain metal ion and scavenges free radicals. It is capable of anti-inflammatory response and anti-oxidative stress so as to protect the brain tissue. During the repair process of brain injury, the latest study showed that MT-I/II could stimulate brain anti-inflammatory factors, growth factors, neurotrophic factors and the expression of the receptor, and promote the extension of axon of neuron, which makes contribution to the regeneration of neuron and has important effect on the recovery of brain injury. Based on the findings, this article reviews the structure, expression, distribution, adjustion, function, mechanism in the repair of brain injury of MT-I/II and its application prospect in forensic medicine. It could provide a new approach for the design and manufacture of brain injury drugs as well as for age estimation of the brain injury.
Animals ; Astrocytes/metabolism* ; Brain/metabolism* ; Brain Injuries/pathology* ; Cytokines/metabolism* ; Forensic Medicine/methods* ; Gene Expression Regulation/drug effects* ; Humans ; Metallothionein/physiology* ; Neurons/metabolism* ; Neuroprotective Agents/pharmacology* ; Oxidative Stress/drug effects*

OBJECTIVE: To investigate the anti-neuroinflammation effect of extract of Fructus Schisandrae chinensis (EFSC) on lipopolysaccharide (LPS)-induced BV-2 cells and the possible involved mechanisms. METHODS: Primary cortical neurons were isolated from embryonic (E17-18) cortices of Institute of Cancer Research (ICR) mouse fetuses. Primary microglia and astroglia were isolated from the frontal cortices of newborn ICR mouse. Different cells were cultured in specific culture medium. Cells were divided into 5 groups: control group, LPS group (treated with 1 μg/mL LPS only) and EFSC groups (treated with 1 μg/mL LPS and 100, 200 or 400 mg/mL EFSC, respectively). The effect of EFSC on cells viability was tested by methylthiazolyldiphenyltetrazolium bromide (MTT) colorimetric assay. EFSC-mediated inhibition of LPS-induced production of pro-inflammatory mediators, such as nitrite oxide (NO) and interleukin-6 (IL-6) were quantified and neuron-protection effect against microglia-mediated inflammation injury was tested by hoechst 33258 apoptosis assay and crystal violet staining assay. The expression of pro-inflammatory marker proteins was evaluated by Western blot analysis or immunofluorescence. RESULTS: EFSC (200 and 400 mg/mL) reduced NO, IL-6, inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2) expression in LPS-induced BV-2 cells (P<0.01 or P<0.05). EFSC (200 and 400 mg/mL) reduced the expression of NO in LPS-induced primary microglia and astroglia (P<0.01). In addition, EFSC alleviated cell apoptosis and inflammation injury in neurons exposed to microglia-conditioned medium (P<0.01). The mechanistic studies indicated EFSC could suppress nuclear factor (NF)-?B phosphorylation and its nuclear translocation (P<0.01). The anti-inflammatory effect of EFSC occurred through suppressed activation of mitogen-activated protein kinase (MAPK) pathway (P<0.01 or P<0.05). CONCLUSION EFSC acted as an anti-inflammatory agent in LPS-induced glia cells. These effects might be realized through blocking of NF-κB activity and inhibition of MAPK signaling pathways.
Animals ; Astrocytes ; drug effects ; metabolism ; pathology ; Cell Line ; Cell Nucleus ; drug effects ; metabolism ; Chromatography, High Pressure Liquid ; Down-Regulation ; drug effects ; Inflammation ; pathology ; Inflammation Mediators ; metabolism ; Lipopolysaccharides ; MAP Kinase Signaling System ; drug effects ; Mice, Inbred ICR ; Microglia ; drug effects ; metabolism ; pathology ; NF-kappa B ; metabolism ; Nervous System ; pathology ; Neurons ; drug effects ; metabolism ; pathology ; Neuroprotective Agents ; pharmacology ; Plant Extracts ; pharmacology ; Schisandra ; chemistry ; Spectrometry, Mass, Electrospray Ionization