OBJECTIVETo investigate the neuroprotective effects of edaravone (Eda) on cobalt chloride (CoCl2)-induced oxidative stress and apoptosis in cultured PC12 cells as well as the underlying mechanisms.

METHODSPC12 cells impaired by CoCl2 were used as the cell model of hypoxia. MTT (methyl thiazolyl tetrazolium) was used to assay the viability of the PC12 cells exposed to Eda with gradient concentrations; Hochest 33258 stain assay was used to analyze the apoptosis ratio of the PC12 cells; Bcl-2 and Bax protein levels in PC12 cells were examined by western blotting. ROS level, the mitochondrial transmembrane potential and caspase-3 activity in each group were detected by spectrofluorometer.

RESULTSCoCl2 treatment caused the loss of cell viability in PC12 cells, which was associated with the elevation of apoptotic rate, the formation of ROS and the disruption of mitochondrial transmembrane potential. CoCl2 also significantly induced the upregulation of Bax/Bcl-2 ratio and the activation of caspase-3. In contrast, Eda significantly reversed these phenotypes, with its maximum protective effect at 0.1 micromol/L.

CONCLUSIONThese results indicated that Eda could protect PC12 cells from CoCl2-induced cytotoxicity, and this protection might be ascribed to its anti-oxidative and anti-apoptotic activities.

Animals ; Antimutagenic Agents ; toxicity ; Antipyrine ; analogs & derivatives ; pharmacology ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Cell Count ; methods ; Cell Survival ; drug effects ; Cobalt ; toxicity ; Dose-Response Relationship, Drug ; Drug Interactions ; Free Radical Scavengers ; pharmacology ; Membrane Potential, Mitochondrial ; drug effects ; PC12 Cells ; drug effects ; Proto-Oncogene Proteins c-bcl-2 ; metabolism ; Rats ; Reactive Oxygen Species ; metabolism ; bcl-2-Associated X Protein ; metabolism

OBJECTIVEThe present study is to observe in vitro the proliferation ability of the muscle cells from permanent myopathy (PM) patients of nomokalaemic periodic paralysis (normKPP), which is caused by mutations of Met1592Val in the skeletal muscle voltage gated sodium channel (SCN4A) gene on chromosome 17q23.1. We also evaluate the possible effect of the foreign basic fibroblast growth factor (bFGF) in preventing and curing PM.

METHODSThe gastrocnemius muscle cells were taken from two male patients with PM of the same Chinese family with Met1592Val mutation of SCN4A, determined by gene screening. Four male patients suffering from the skeletal injury without PM were taken as control. All preparations were protogenerationally cultured in vitro. Proliferation of the cultured preparations was measured by MTT. Activities of the lactic dehydrogenase (LDH), creatine kinase (CK), and protein content in these cells were also detected. The effects of bFGF with different doses (10 ng/mL, 20 ng/mL, 40 ng/mL, 80 ng/mL, 120 ng/mL and 160 ng/mL) on the above mentioned parameters were also evaluated.

RESULTSCells from both PM and control subjects were successfully cultured in vitro. The cultivation of the muscle cells from PM patients in vitro was not yet seen. Results indicated the obvious stimulation of bFGF on cell proliferation, activities of LDH and CK, protein synthesis, in a dose dependent manner. The optimal dose of bFGF was 120 ng/mL (P<0.05), beyond which greater dose caused a less effect. The effect of bFGF on 160 ng /mL was stronger than that on 80 ng/mL, but there was no significant difference (P>0.05).

CONCLUSIONMyoblastic cells from patients with PM had a weaker ability of developing into the myotubules, thus they were unable to perform effective regeneration, which resulted in a progressive necrosis. The exogenous bFGF could promote the division and proliferation of the muscle cells in vitro. These results shield a light on bFGFos potential role in preventing and treating PM.

Adult ; Cell Proliferation ; drug effects ; Cells, Cultured ; Creatine Kinase ; metabolism ; Dose-Response Relationship, Drug ; Fibroblast Growth Factor 2 ; pharmacology ; Humans ; L-Lactate Dehydrogenase ; metabolism ; Male ; Methionine ; genetics ; Middle Aged ; Muscle Development ; genetics ; physiology ; Muscular Diseases ; genetics ; pathology ; Mutation ; genetics ; Myoblasts ; drug effects ; NAV1.4 Voltage-Gated Sodium Channel ; Sodium Channels ; genetics ; Valine ; genetics

OBJECTIVETo prepare and identify a polyclonal antibody against rat myostatin and investigate myostatin expression in the rat atrophic gastrocnemius muscle after tibial nerve crush.

METHODSThe purified fusion protein was used as antigen to immunize rabbits for the preparation of polyclonal antibody. The polyclonal antibody of the protein was measured by enzyme linked immunosorbent assay (ELISA), western-blot and immunochemistry. Myostatin protein expression levels in normal and atrophic gastrocnemius muscle were detected by western-blot and immunochemistry assays.

RESULTSThe GST-myostatin had a purity of 96% and possessed high titer and specificity. The level of myostatin in gastrocnemius muscle significantly increased one week after tibial nerve crush, reached the peak on day 14, and then returned to normal level on day 28.

CONCLUSIONWe have successfully made antiserum of rat myostatin and found that the expression level of myostatin protein in the gastrocnemius after tibial nerve crush-induced atrophy was time-dependent. This study provides an experimental basis to clarify the possible role of myostatin during skeletal muscle atrophy.

Analysis of Variance ; Animals ; Antibodies ; blood ; Enzyme-Linked Immunosorbent Assay ; methods ; Female ; Gene Expression Regulation ; physiology ; Immune Sera ; Immunization ; methods ; Male ; Muscle, Skeletal ; metabolism ; Myostatin ; immunology ; Rabbits ; Rats ; Rats, Sprague-Dawley ; Recombinant Fusion Proteins ; immunology ; Tibial Neuropathy ; metabolism ; pathology ; Time Factors

OBJECTIVETo explore the possible differential trafficking properties of the dopamine D1-like receptor subtypes, D1 receptor and D5 receptor.

METHODSTo visualize distributions of dopamine D1-like receptor subtypes at subcellular level, the yellow and cyan variants of green fluorescent protein (GFP) were used to tag D1 and D5 receptors. After transfection with the tagged dopamine receptors, the neuroblastoma cells NG108-15 were treated with D1 agonist SKF38393 or acetylcholine (ACh). Then we observed the subcellular distributions of the tagged receptors under the confocal microscopy and tried to determine trafficking properties by comparing their distribution patterns before and after the drug treatment.

RESULTSIn resting conditions, D1 receptors located in the plasma membrane of NG108-15 cells, while D5 receptors located in both plasma membrane and cytosol. With the pre-treatment of SKF38393, the subcellular distribution of D1 receptors was changed. The yellow particle-like fluorescence of tagged D1 receptors appeared in the cytosol, indicating that D1 receptors were internalized into cytosol from the cell surface. Same situation also occurred in ACh pre-treatment. In contrast, the subcellular distribution of D5 receptors was not changed after SKF38393 or ACh treatment, indicating that D5R was not translocated to cell surface. Interestingly, when D1 and D5 receptors were co-expressed in the same cell, both kept their distinct subcellular distribution patterns and the trafficking properties.

CONCLUSIONOur present study reveals that in NG108-15 nerve cells, dopamine D1 and D5 receptors exhibit differential subcellular distribution patterns, and only D1 receptor has a marked trafficking response to the drug stimulation. We further discuss the potential role of the differential trafficking properties of D1-like receptors in complex modulation of DA signaling.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine ; pharmacology ; Acetylcholine ; pharmacology ; Animals ; Cell Line ; Dopamine Agonists ; pharmacology ; HeLa Cells ; Humans ; Luminescent Proteins ; genetics ; Mice ; Microscopy, Confocal ; methods ; Neuroblastoma ; Protein Transport ; drug effects ; Rats ; Receptors, Dopamine D1 ; metabolism ; Receptors, Dopamine D5 ; metabolism ; Subcellular Fractions ; metabolism ; ultrastructure ; Transfection ; methods

This review focused on the diagnosis and clinical features of multiple sclerosis (MS) in China. We have identified the published researching information from 1976 to 2008 in China. The key issues related to the diagnosis and clinical features of MS in China were summarized. The first patient with MS in China was reported in 1926 from Xiehe hospital. Case reports on MS have been increasing during recent decades. Almost all the patients with MS were confirmed by the McDonald criteria (1977) before 1984. After the year of 1992, even to this day, the Poser criteria were widely used in China. Although the new diagnostic criteria, McDonald criteria (2001), were presented in 2001, only few papers published in Chinese were reported. The most frequent initial symptoms or signs of the patients with MS were optic nerve, motor weakness and sensory symptoms. The most frequent location of MS lesions over the course was found to be the spinal cord, followed by the cerebrum and optic nerves. Almost all patients had been treated with corticosteroids. This review supported previous observations in Chinese patients with MS. However, further studies are needed to understand epidemiologic features of MS in China.
China ; epidemiology ; Humans ; Multiple Sclerosis ; diagnosis ; epidemiology ; physiopathology ; therapy

Perivascular space (PVS) is a crevice between two slices of cerebral pia maters, filled with tissue fluid, which be formed by pia mater emboling in the surrounding of cerebral perforating branch (excluding micrangium). Normal PVS (diameter < 2 mm) can be found in almost all healthy adults; however enlarged PVS (diameter > 2 mm) has correlation with neurological disorders probably. The article reviews the formation mechanism, imageology characteristics and the relation with neurological disorders of PVS, which is beneficial to the research of some neurological disorders etiopathogenesis and treatment.
Animals ; Blood Vessels ; pathology ; Humans ; Nervous System Diseases ; pathology ; Pia Mater ; pathology

Extracellular adenosine 5 inch-triphosphate (ATP) is a key signaling molecule present in the central nervous system (CNS), and now is receiving greater attention due to its role as a messenger in the CNS during different physiological and pathological events. ATP is released into the extracellular space through vesicular exocytosis or from damaged and dying cells. Once in the extracellular environment, ATP binds to the specific receptors termed P2, which mediate ATP effects and are present broadly in both neurons and glial cells. There are P2X, the ligand-gated ionotropic receptors, possessing low affinity for ATP and responsible for fast excitatory neurotransmission, and P2Y, the metabotropic G-protein-coupled receptors, possessing high affinity for ATP. Since massive extracellular release of ATP often occurs after stress, brain ischemia and trauma, the extracellular ATP is considered relating to or involving in the pathological processes of many nervous system diseases. Conversely, the trophic functions have also been extensively described for the extracellular ATP. Therefore, extracellular ATP plays a very complex role in the CNS and its binding to P2 receptors can be related to toxic and/or beneficial effects. In this review, we described the extracellular ATP acting via P2 receptors as a potent therapeutic target for treatment of nervous system diseases.
Adenosine Triphosphate ; metabolism ; therapeutic use ; Animals ; Extracellular Fluid ; metabolism ; Humans ; Nervous System Diseases ; drug therapy ; metabolism ; Receptors, Purinergic P2 ; physiology

OBJECTIVETo investigate the underlying mechanism for the selective modulation of the permeability of blood-tumor barrier (BTB) by small dose of bradykinin (BK).

METHODSC6 glioma cells were treated with BK, and changes of intracellular nitric oxide (NO) and intracellular calcium level were measured with fluorescent spectrophotometer.

RESULTSThe initial application of BK easily triggered extracellular calcium influx, which resulted in intracellular calcium store release in C6 glioma cells. The above mechanism was also named ryanodine mediated calcium induced calcium release (CICR). We also detected a long-lasting intracellular NO elevation in C6 glioma cells upon BK treatment. Further study showed that ryanodine mediated CICR contributed greatly to the secondary NO elevation induced by BK treatment.

CONCLUSIONThese results suggested that BK triggered CICR in C6 glioma cells and the associated NO generation might be the underlying mechanism for the selective modulation of BTB permeability by BK.

Animals ; Bradykinin ; pharmacology ; Calcium ; metabolism ; Cell Line, Tumor ; Glioma ; pathology ; Intracellular Fluid ; drug effects ; Nitric Oxide ; metabolism ; Rats ; Ryanodine ; pharmacology ; Spectrometry, Fluorescence ; methods ; Time Factors

OBJECTIVETo investigate the changes in the firing activity of noradrenergic neurons in the locus coeruleus (LC) in a rat model of Parkinson disease (PD).

METHODS2 and 4 weeks after unilateral lesion of the nigrostriatal pathway in the rat by local injection of 6-hydroxydopamine (6-OHDA) into the right substantia nigra pars compacta (SNc), the firing activity of noradrenergic neurons in LC was recorded by extracellular single unit recording.

RESULTSThe firing rate of LC noradrenergic neurons increased significantly 2 and 4 weeks after 6-OHDA lesions compared to normal rats, respectively (P < 0.05). The percentage of irregularly firing neurons was obviously higher than that of normal rats during the fourth week after SNc lesion (P < 0.05).

CONCLUSIONLC noradrenergic neurons are overactive and more irregular in 6-OHDA-lesioned rats. These changes suggest an implication of the LC in the pathophysiological mechanism of PD.

Action Potentials ; physiology ; Animals ; Disease Models, Animal ; Locus Coeruleus ; pathology ; Male ; Neurons ; physiology ; Norepinephrine ; metabolism ; Oxidopamine ; Parkinsonian Disorders ; chemically induced ; pathology ; Rats ; Rats, Sprague-Dawley ; Time Factors

OBJECTIVETo observe the change of the neuropeptide pro-protein processing system in the ischemic retina ganglion cell-5 (RGC-5) cells, pro-protein convertase-2 (PC2), carboxypeptidase-E (CPE) and preproneuropeptide Y (preproNPY) protein levels in the ischemic RGC-5 cells and conditioned medium were analyzed.

METHODSThe RGC-5 cell was differentiated in 0.1 mumol/L staurosporine for 24 h and then stressed by different doses of oxygen and glucose deprivation (OGD). The acute or chronic OGD-induced cell death rates were obtained by using PI or TUNEL staining. The protein expression levels were determined by using the Western blot method and PC2 activity analysis.

RESULTSThe ischemia caused substantial cell death in an OGD dose-dependent manner. In the cells, proPC2 and preproNPY protein levels gradually increased whereas proCPE gradually decreased. After OGD, PC2 activity was decreased. In the conditioned medium, proPC2 and PC2 proteins gradually decreased whereas proCPE, CPE, and preproNPY proteins gradually increased.

CONCLUSIONThese results demonstrated that OGD inhibited the neuropeptide pro-protein processing system by reducing PC2 activity and the maturation of proPC2. The aggregation of the pro-proteins and the increase of the active CPE excision adversely exacerbated the cell injury. The pro-protein processing system might play a critical role in the ischemic stress of RGC-5 cells.

Animals ; Carboxypeptidase H ; metabolism ; Cell Death ; drug effects ; physiology ; Cell Differentiation ; drug effects ; Cell Hypoxia ; drug effects ; physiology ; Cell Line, Transformed ; Enzyme Inhibitors ; pharmacology ; Gene Expression Regulation, Enzymologic ; drug effects ; physiology ; Glucose ; deficiency ; In Situ Nick-End Labeling ; methods ; Indoles ; Neuropeptide Y ; metabolism ; Proprotein Convertase 2 ; metabolism ; Protein Precursors ; metabolism ; Rats ; Retinal Ganglion Cells ; drug effects ; metabolism ; Staurosporine ; pharmacology ; Time Factors