Three-dimensional motion analysis for GLUT4 vesicles in TIRF microscopy / 中国医疗器械杂志

In this paper, GLUT4 vesicles are observed in real-time under TIRF microscopy and a new three-dimensional single particle tracking algorithm according to the unique features of TIRF is put forward. Firstly a fluorescence correction procedure was processed to solve the problem of fluorescence bleaching over time and mobile vesicles were segmented by an adaptive background subtraction method. Kalman filtering was then introduced to track the granules so as to reduce the searching range and to avoid the disturbance of background noise and false targets. In the experiments the algorithm was applied in analyzing the long-distance movement of GLUT4 vesicles. The experimental results indicate that the algorithm has achieved robust tracking of the vesicles in the imaging plane and has effectively calculated the position in the direction orthogonal to the imaging plane.

Protective effects of breviscapine against cultured rat hippocampal neuronal toxicity induced by glutamate / 药学学报

The aim of this study was to investigate the effects of breviscapine on cultured rat hippocampal neuronal toxicity induced by glutamate. Primary hippocampal neurons were prepared from 2 day-old SD rats. After 8 days cultured in vitro, the cultures subjected to 30 min treatment of 0.1, 0.5 and 1.0 mmol x L(-1) L-glutamate, separately. Breviscapine (10, 20 and 40 micromol x L(-1)) was added into the cultures during 30 min treatment of L-glutamate and for the following 24 h respectively. After 24 h of L-glutamate treatment, flow cytometric analysis of Annexin V (marks apoptosis) and PI (propidium iodide, marks necrosis) labeling cells showed that L-glutamate dose-dependently induced hippocampal neuronal apoptosis and necrosis. In agreement with these results, RT-PCR experiments indicated a biphasic regulation of X-chromosome-linked inhibitor of apoptosis protein (XIAP) mRNA after L-glutamate treatment, i. e up-regulation by 0.1 mmol x L(-1) L-glutamate and down-regulation by 0.5 and 1.0 mmol x L(-1) L-glutamate. However, breviscapine markedly reduced apoptosis and necrosis due to toxicity of 0.5 mmol L(-1) L-glutamate. Compared with the vehicle-treated L-glutamate group, the apoptosis was reduced by 30.4% and 40.1%, and necrosis was reduced by 32.5% and 38.8%, after treatment by breviscapine of 20 and 40 micromol x L(-1). Meanwhile, breviscapine obviously reversed the down-regulation of XIAP expression induced by L-glutamate (up-regulation by 45.1% and 54.9% when compared with that of the vehicle-treated glutamate group). The results from the detection of confocal laser scanning microscopy with Fluo-3, a Ca2+ probe showed an obvious increase in intracellular Ca2+ during L-glutamate treatment; and breviscapine of 20 or 40 micromol x L(-1) significantly slowed down glutamate-induced Ca2+ influx and lowered the intracellular Ca2+ peak in hippocampal neurons (P < 0.01). These results suggest that neuroprotective effect of breviscapine against glutamate excitotoxicity was associated with inhibition of the accumulation of intracellular Ca2+ and up-regulation of XIAP expression in hippocampal neurons.

Inhibition of excitatory amino acid efflux contributes to protective effects of puerarin against cerebral ischemia in rats / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate whether the protective effects of puerarine (Pur) against cerebral ischemia is associated with depressing the extracellular levels of amino acid transmitters in brain of rats.</p><p><b>METHODS</b>Male Sprague-Dawley rats were subjected to transient middle cerebral artery occlusion (MCAO) for 60 min followed by 24 h reperfusion. Pur (50, 100 mg/kg, i.p.) was administered at the onset of MCAO. The infarct rate and edema rate were detected on TTC (2,3,5-triphenyltetrazolium chloride)-stained coronal sections. The extracellular levels of amino acid transmitters were monitored in striatum of rats with ischemic/reperfusion injury using in vivo microdialysis technique. Furthermore, the protective effects of Pur against glutamate-induced neurotoxicity were detected. Glutamate-induced apoptotic and necrotic cells in hippocampus were estimated by flow cytometric analysis of Annexin-V and PI labeling cells.</p><p><b>RESULTS</b>Pur (100 mg/kg) significantly decreased infarct size by 31.6% (P<0.05), reduced edema volume (P<0.05), and improved neurological functions (P<0.05) following MCAO. In these rats, the ischemia-induced extracellular levels of aspartate (Asp), glutamate (Glu), y-aminobutyric acid (GABA), and taurine (Tau) were significantly reduced in striatum of vehicle-treated animals by 54.7%, 56.7%, 75.8%, and 68.1% (P<0.01 and P<0.05). Pur reduced the peak values of Glu and Asp more obviously than those of GABA and Tau, and the rate of Glu/GABA during MCAO markedly decreased in Pur-treated MCAO rats, compared with the vehicle-treated MCAO rats. Meanwhile, apoptosis and necrosis induced by Glu in cultured hippocampal neurons were significantly reduced after Pur treatment.</p><p><b>CONCLUSION</b>Acute treatment with Pur at the onset of occlusion significantly depresses ischemia-induced efflux of amino acids, especially, excitotoxicity in the striatum, a mechanism underlying the neuroprotective effect on cellular survival.</p>

Effect of dialysis time in vivo on recovery of amino acids for micro-dialysis probe / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To investigate the variety of vitro recovery of amino acids for microdialysis probe after different dialysis time in vivo.</p><p><b>METHODS</b>Probes were dialyzed in the amino acids standard solutions with microdialysis system,amino acid standard solutions and the microdialysate of probe were detected by the method of precolumn derivation with HPLC-RF.</p><p><b>RESULT</b>After using different time of probe made by regenerated cellulose membrane, the vitro recoveries of Asp, Glu and GABA were not completely same (Asp: F=19.669, P=0.000; Glu: F=103.955, P=0.000; GABA: F=3.454, P=0.040); while the vitro recovery of Tau had no obvious difference(F=2.001, P=0.152). After using 6 h in vivo, recovery remain percentage (RRP) of Asp, Glu,Tau and GABA was 64.34 %, 67.36%, 103.11 % and 98.23 %, respectively, the recoveries of Asp, Glu decreased obviously (Asp: P < 0.01,Glu: P <0.05). After using 12 h in vivo, the RRP of Asp, Glu, Tau and GABA was 43.44 %, 24.42%, 77.45 % and 67.36 %, respectively, the recoveries of Asp, Glu and GABA decreased obviously (Asp: P < 0.001, Glu: P < 0.001, GABA: P < 0.05). After using 24 h in vivo, the RRP of Asp, Glu,Tau and GABA was 36.26 %, 12.24 %, 89.48 % and 71.35 %, respectively, the recoveries of Asp, Glu, GABA decreased obviously (Asp: P < 0.0001, Glu: P < 0.0001, GABA: P < 0.01).</p><p><b>CONCLUSION</b>Dialysis in vivo could lead to the decline of recovery of probe, the decline is more obvious after longer dialysis. So when making brain dialysis experiments, the use time of probe should not be too long. To improve the validity of data, some calibration should be made on the recoveries of probe.</p>

Activity of Ginkgo biloba extract and quercetin on thrombomodulin expression and tissue-type plasminogen activator secretion by human umbilical vein endothelial cells / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>In order to investigate the pharmacological properties of Ginkgo biloba extract (GBE) on improving blood circulation, the regulating action of GBE and quercetin (a main flavonoid ingredient in GBE) on thrombomodulin (TM) expression and tissue-type plasminogen activator (t-PA) secretion was studied.</p><p><b>METHODS</b>Using flow cytometer and gel image system respectively, we evaluated the TM expression and the t-PA secretion by human umbilical vein endothelial cells (HUVECs) in vitro.</p><p><b>RESULTS</b>The increase of TM expression on HUVECs surface was induced by GBE rather than quercetin in a dose- and time-dependent manner. Both GBE and quercetin increased the t-PA release significantly.</p><p><b>CONCLUSION</b>The effect of GBE on improving blood circulation may be partly attributed to its promoting TM expression and t-PA secretion by endothelial cells, and quercetin participated in the effect of GBE on t-PA secretion. However, the action of GBE on increasing TM expression needs further study.</p>

Inhibitory effects of jujuboside A on EEG and hippocampal glutamate in hyperactive rat / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

In this study, the inhibitory effect of jujuboside A (JuA) on a penicillin sodium (Na-PCN) induced hyperactivity model was investigated. Cortical EEG (electroencephalogram) and the concentration of hippocampal Glutamate (Glu) were monitored simultaneously in vivo as indicators of rat's excitatory state. Power spectral density (PSD) and gravity frequency of PSD were calculated. JuA (0.05 g/L and 0.1 g/L) inhibited the EEG excitation effect caused by Na-PCN by increasing the power of delta1 and delta2 bands (P<0.01 vs model) and lowering the gravity frequency of PSD (P<0.01 vs model). JuA also remarkably reduced the Glu elevation induced by Na-PCN (P<0.05 vs model). Diazepam also depressed Glu concentration and lowered the gravity frequency, but it showed a different EEG pattern in increased beta2-activity (P<0.01 vs model). EEG excitation caused by Na-PCN correlated with Glu elevation during the first hour. Neurophysiological inhibitory effects of JuA and diazepam were more persistent than their Glu inhibitory effects.

Effect of l-tetrahydropalmatine on expression of adhesion molecules induced by lipopolysaccharides in human umbilical vein endothelium cell / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effect of l-tetrahydropalmatine (l-THP) on adhesion molecule expression induced by LPS in human umbilical vein endothelium cell (HUVEC).</p><p><b>METHOD</b>HUVEC were obtained from the human umbilical cord vein and treated by LPS or LPS plus different concentration of l-THP. Expression of ICAM-1 and E-selectin was assayed by flow cytometer.</p><p><b>RESULT</b>l-THP(250 mg x L(-1)) markedly attenuated ICAM-1 and E-selectin expression induced by LPS(P <0.05). l-THP(50 mg x L(-1) inhibited E-selectin expression (P < 0.05) but had no effect on ICAM-1 (P > 0.05). l-THP (10 mg x L(-1)) had no effect on expression of both adhesion molecules. DXM (50 mg x L(-1)) completely inhibited both responses induced by LPS (P < 0.05).</p><p><b>CONCLUSION</b>l-THP depresses expression of ICAM-1 and E-selectin induced by LPS, which suggests that I-THP represent a promising candidate to be developed into therapies for the treatment of inflammation.</p>

Inducible nitric oxide synthase and NFκB signaling in amyloid β-peptide induced neuron death and apoptosis / 中华神经医学杂志

Amyloid β-peptide (Aβ) stimulating inducible nitric oxide synthase (iNOS) induces neuron death or apoptosis through the transcription factor NFκB (nuclear factor κB) signal pathway mechanism. Aβ functiones together with microglia and astrocyte to stimulate the inflammatory responsecorrelative with expression ofiNOS, the activation of the NFκB signal pathway and the expression ofiNOS,which results in significant peroxynitrite damage to neurons and the neurodegeneration in Alzheimer's disease (AD). Activation of CD36 signaling in microgila by Aβ fibrils initiates the association of the Src-family kinase Lyn with CD36. Together with another Src kinase, Fyn, Lyn activates a MAPK signaling response and results in the activation of inflammatory programs such as the production of MCP-1 and ROS.In parallel, Syk-family kinase activity specifically regulates increased cytokine production in response to Aβstimulation. After the stimulation, NFκB works independent of Src and Syk activation. Aβ-stimulated microglial secretes TNF-α and O2-, resulting in iNOS overexpression and excessive peroxynitrite and neuronal apoptosis.

Effects of L-tetrahydropalmatine on concentrations of neurotransmitter amino acids in mice with cerebral ischemia / 中国中药杂志

<p><b>OBJECTIVE</b>To observe the effects of L-tetrahydropalmatine (L-THP) on concentrations of neurotransmitter amino acids in mice with cerebral ischemia and to discuss the mechanisms of L-THP in tyreating cerebral ischemia.</p><p><b>METHOD</b>Mice were randomly divided into six groups: control group, cerebral ischemia group, L-THP treated group (doses were 14, 28, 56 mg x kg(-1) respectively) and Ginkgo biloba extract treated group. Concentrations of Glu and GABA were determined by HPLC.</p><p><b>RESULT</b>Compared with control group, Glu and GABA in mice with cerebral ischemia were much higher. The ratio of Glu/GABA increased significantly. L-THP markedly reduced the concentrations of Glu and the ratio of Glu/GABA in mice with cerebral ischemia.</p><p><b>CONCLUSION</b>Decrease in Glu concertration and ratio of Glu/GABA may be one of the mechanisms of L-THP in treating cerebral ischemia.</p>

Sedative and anticonvulsant effect of jujuboside A / 浙江大学学报·医学版

OBJECTIVE: To study the sedative effects of Jujuboside A (JuA) on the Central Nervous System of mice. METHODS: Using a novel jiggle-cage test, we compared the sedative effect of JuA with that of Diazepam (DZP) both with a single and cumulative dose of JuA. We also assessed the anticonvulsant effect of JuA on pentylenetetrazol (PTZ)-induced seizures in mice. RESULTS: JuA significantly decreased total activity intensity and increased the quiet state time of mice. The sedative effects of JuA were more stable and more lasting than that of DZP. However, JuA failed to resist and delay the induced seizure activity in mice. CONCLUSION: Though JuA has sedative effects on mice CNS, it has no anticonvulsant effect on PTZ-induced seizures.

Changes of element contents and their interrelationship in tibia of osteoporotic rats / 浙江大学学报·医学版

OBJECTIVE: To observe the changes of bone element contents in osteoporosis and their interrelationship. METHODS: Twelve female SD rats,10-month-old, were bilaterally ovariectomized (OVX group) and another ten rats were received sham-operation under anesthesia (SHAM group).The element contents in tibia, including Ca, P, Mg, Zn, Mn, Fe, Cu, Mo and Cr, were determined by atomic absorption spectrophotometer 7 month later. The data of contents of all elements were analyzed by simple regression. RESULTS: Compared with the SHAM group rats, the contents of Ca, P and Mg were decreased by 6.6 %(P<0.05), 6.3 %(P<0.05) and 14.9 %(P<0.01) respectively. The contents of Zn and Fe were reduced by 15.2 %(P<0.01) and 35.1 %(P<0.01) separately, Mo and Cr were decreased by 12.2 %(P>0.05) and 14.0 %(P>0.05), while the contents of Mn, Cu and Co were shown no change. There was a significant correlation among the contents of Mg, Mn, Zn, Ca and P. CONCLUSION: The contents of Ca, P, Mg, Zn and Fe were matkedly reduced in bone of osteoporotic rats induced by ovariectomy.