The expression of both constitutive and inducible forms of nitric oxide synthase (NOS) was investigated by immunohistochemical staining of formalin-fixed paraffin-embedded sections in normal and Listeria monocytogenes-infected brains of goats. In normal control goats, a small number of neurons showed immunoreactivity of both iNOS and nNOS, and the number of iNOS-positive neurons was higher than the number of nNOS-positive neurons. In natural listeriosis, listeria antigens were easily immunostained in the inflammatory cells of microabscesses. In this lesion, the immunoreactivity of iNOS in neurons was more intense than the control, but nNOS was not. In microabscesses, nNOS was weakly visualized in macrophages and neutrophils, while iNOS was expressed in macrophages, but not in neutrophils. These findings suggest that normal caprine brain cells, including neurons, constitutively express iNOS and nNOS, and the expressions of these molecules is increased in Listeria monocytogenes infections. Furthermore, inflammatory cells, including macrophages, expressing both nNOS and iNOS may play important roles in the pathogenesis of bacterial meningoencephalitis in goat.
Animals ; Brain/cytology/*enzymology ; Glial Fibrillary Acidic Protein/analysis ; Goat Diseases/*enzymology ; Goats ; Immunohistochemistry ; Listeria Infections/enzymology/*veterinary ; Neurons/*enzymology ; Nitric Oxide Synthase/*analysis ; Nitric Oxide Synthase Type I ; Nitric Oxide Synthase Type II

OBJECTIVEThe present study investigated the inhibitory effects of Chinese herb component sinapine on activity of acetylcholinesterase (AChE) in cerebral homogenate and blood serum of rats.

METHODAChE was prepared from cerebral homogenate and blood serum of rats, respectively. Acetylcholinesterase activity assay kit and Chromatometry were used to detect the AChE activity.

RESULTSinapine significantly inhibited AChE activity in vitro, with more effective on cerebral homogenate (IC50 3.66 micromol x L(-1)) than blood serum (IC50 22.1 micromol x L(-1)).

CONCLUSIONSinapine could significantly inhibit the cerebral AChE activity and may be a promising drug used for prevention and cure of Alzheimer's disease as a cholinesterase inhibitor.

Acetylcholinesterase ; blood ; metabolism ; Alzheimer Disease ; drug therapy ; prevention & control ; Animals ; Brain ; cytology ; enzymology ; Choline ; analogs & derivatives ; pharmacology ; therapeutic use ; Cholinesterase Inhibitors ; pharmacology ; therapeutic use ; Rats

OBJECTIVETo study the changes of serum neuron specific enolase in rats with septic shock.

METHODSThe model of septic shock was set up by injection of lipopolysaccharide (LPS, from Escherichia coil O55: B5) at a dose of 25 mg/kg through femoral vein. Twenty male Wistar rats were randomly divided into 2 groups: normal control group (LPS was substituted by same volume of normal saline solution) and septic shock group. Six hours after the septic shock model formed, whole blood was taken for measuring the serum neuron specific enolase (NSE). The brains of the rats were taken for histopathological examination.

RESULTSThe serum NSE of septic shock group was significantly higher than that of control group [(10.0781 +/- 0.526) microg/L vs. (3.7188 +/- 0.602) microg/L, P < 0.05]. Neurons were severely damaged 6 hours after injection of LPS. Neuronal necrosis and the damage of blood-brain barrier were seen by light and electron microscope in septic shock group but not in the control group.

CONCLUSIONNSE in serum increased when septic encephalopathy occurred, which indicated that NSE might become a marker of neural damage in septic shock.

Animals ; Biomarkers ; blood ; Blood Pressure ; Blood-Brain Barrier ; ultrastructure ; Brain ; cytology ; pathology ; Cell Death ; Disease Models, Animal ; Male ; Microscopy, Electron ; Neurons ; pathology ; ultrastructure ; O Antigens ; toxicity ; Phosphopyruvate Hydratase ; blood ; Rats ; Rats, Inbred BB ; Shock, Septic ; blood ; enzymology ; pathology

OBJECTIVEExtracellular signal-regulated kinases (ERKs) can be activated by calcium signals. In this study, we investigated whether calcium-dependent kinases were involved in ERKs cascade activation after global cerebral ischemia.

METHODSCerebral ischemia was induced by four-vessel occlusion, and the calcium-dependent proteins were detected by immunoblot.

RESULTSLethal-simulated ischemia significantly resulted in ERKs activation in N-methyl-D-aspartate (NMDA) receptor-dependent manner, accompanying with differential upregulation of Src kinase and Ca2+/calmodulin-dependent protein kinase II (CaMKII) activities. With the inhibition of Src family tyrosine kinases or CaMKII by administration of PP2 or KN62, the phosphorylation of ERKs was impaired dramatically during post-ischemia recovery. However, ischemic challenge also repressed ERKs activity when Src kinase was excessively activated.

CONCLUSIONSrc family tyrosine kinases and CaMKII might be involved in the activation of ERKs mediated by NMDA receptor in response to acute ischemic stimuli in vivo, but the intense activation of Src kinase resulted from ischemia may play a reverse role in the ERKs cascade.

Analysis of Variance ; Animals ; Brain Ischemia ; enzymology ; pathology ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; Calcium-Calmodulin-Dependent Protein Kinases ; metabolism ; Disease Models, Animal ; Extracellular Signal-Regulated MAP Kinases ; metabolism ; Gene Expression Regulation ; physiology ; Hippocampus ; cytology ; enzymology ; Male ; Neurons ; enzymology ; pathology ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Receptors, N-Methyl-D-Aspartate ; metabolism ; Signal Transduction ; physiology ; Statistics, Nonparametric ; src-Family Kinases ; metabolism

OBJECTIVETo study the anti-glioma activity of treatment by bone marrow stromal cells (BMSCs) transfected with AdCMV-tk containing HSV-tk gene in rats.

METHODSPrimary cultured BMSCs were obtained and transfected with HSV-tk (BMSCs/tk) and were injected into contralateral brain of glioma-bearing rats to observe their tropism for glioma cells. RT-PCR was performed to examine the transduct of tk gene after it was transduced into BMSCs. C6 glioma cells were co-cultured with BMSCs transfected with HSV-tk. MTT test was performed to examine its antitumor activity. BMSCs, after being transfected with HSV-tk, were injected into contralateral brain tissue of glioma-bearing rats to show their in vivo antitumor activity. Dynamic MRI was performed to monitor the development of intracranial glioma.

RESULTSPurified BMSCs were obtained by primary cultured bone marrow cells. After being transfected with HSV-TK, the cells still stably displayed extensive tropism for intracranial glioma and transcripted tk gene. RT-PCR showed that BMSCs/tk were transduced tk gene obviously at 21 days after AdCMV-tk transfection. BMSCs/tk showed a clear bystander effect after being co-cultured with C6 glioma cells in vitro. TUNEL assay showed that BMSCs/tk could obviously show bystander effect and induce apoptosis of glioma cells in vivo with an apoptosis positive ratio of 20.38% +/- 2.57%, showing a statistically significant difference in comparison with BMSCs group (2.56% +/- 0.52%, P = 0.023) and control group (2.74% +/- 0.38%, P = 0.025). Compared with the control group (21.40 +/- 1.63 days), BMSCs/tk transplantation significantly prolonged the survival time of glioma-bearing rats (52.60 +/- 13.11 days, P = 0.000). MRI detection showed that the least volume of intracranial glioma in BMSCs/tk group (8.28 +/- 2.64 mm3), significantly smaller than that in BMSCs group (134.51 +/- 16.37 mm3, P = 0.001) and control group (147.22 +/- 31.05 mm3, P = 0.001). Some of the intracranial gliomaa disappeared after transplantation of BMSCs/tk.

CONCLUSIONBMSCs transfected with AdCMV-tk may become an effective therapy method in the treatment for glioma.

Animals ; Apoptosis ; Bone Marrow Cells ; cytology ; Brain ; pathology ; Bystander Effect ; Cell Line, Tumor ; Coculture Techniques ; Genetic Therapy ; methods ; Glioma ; pathology ; therapy ; Magnetic Resonance Imaging ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Simplexvirus ; enzymology ; Stromal Cells ; cytology ; enzymology ; transplantation ; Thymidine Kinase ; genetics ; metabolism ; Transfection

Brain-derived neurotrophic factor (BDNF)is the richest neurophin in brain tissue and may act as an activity-dependent neuronal survival factor. In vitro, BDNF plays an important role in preventing cortical neurons from hypoxia-induced neurotoxicity. It could induce a variety of cellular responses such as cell growth, survival, differentiation, and anti-apoptosis mainly via activating mitogen-activated protein kinase (MAPK) and Ca2+/calmodulin-dependent kinase (CaMK) signaling pathways. And among these multiple signaling pathways there is growing evidence of complicated cross talk.
Animals ; Brain-Derived Neurotrophic Factor ; pharmacology ; physiology ; Calcium-Calmodulin-Dependent Protein Kinase Type 2 ; Calcium-Calmodulin-Dependent Protein Kinases ; drug effects ; physiology ; Cells, Cultured ; Humans ; Mitogen-Activated Protein Kinases ; drug effects ; physiology ; Neurons ; cytology ; drug effects ; enzymology ; Signal Transduction

BACKGROUNDC-Jun N-terminal kinase (JNK) signaling pathway plays a critical role in cerebral ischemia. Although the mechanistic basis for this activation of JNK1/2 is uncertain, oxidative stress may play a role. The purpose of this study was to investigate whether the activation of JNK1/2 is associated with the production of endogenous nitric oxide (NO).

METHODSIschemia and reperfusion (I/R) was induced by cerebral four-vessel occlusion. Sprague-Dawley (SD) rats were divided into 6 groups: sham group, I/R group, neuronal nitric oxide synthase (nNOS) inhibitor (7-nitroindazole, 7-NI) given group, inducible nitric oxide synthase (iNOS) inhibitor (2-amino-5,6-dihydro-methylthiazine, AMT) given group, sodium chloride control group, and 1% dimethyl sulfoxide (DMSO) control group. The levels of protein expression and phospho-JNK1/2 were detected by Western blotting and the survival hippocampus neurons in CA1 zone were observed by cresyl violet staining.

RESULTSThe study illustrated two peaks of JNK1/2 activation occurred at 30 minutes and 3 days during reperfusion. 7-NI inhibited JNK1/2 activation during the early reperfusion, whereas AMT preferably attenuated JNK1/2 activation during the later reperfusion. Administration of 7-NI and AMT can decrease I/R-induced neuronal loss in hippocampal CA1 region.

CONCLUSIONJNK1/2 activation is associated with endogenous NO in response to ischemic insult.

Animals ; Blotting, Western ; Brain Ischemia ; enzymology ; Enzyme Inhibitors ; Hippocampus ; cytology ; metabolism ; Indazoles ; pharmacology ; Male ; Mitogen-Activated Protein Kinase 8 ; metabolism ; Mitogen-Activated Protein Kinase 9 ; metabolism ; Neurons ; cytology ; metabolism ; Nitric Oxide ; metabolism ; Nitric Oxide Synthase Type II ; antagonists & inhibitors ; Phosphorylation ; drug effects ; Rats ; Rats, Sprague-Dawley