Ephrin-B2 has been shown to participate in angiogenesis, but the underlying mechanisms involved remain unclear. In this study, a rat model of local cerebral ischemia was prepared by focal middle cerebral artery occlus...Ephrin-B2 has been shown to participate in angiogenesis, but the underlying mechanisms involved remain unclear. In this study, a rat model of local cerebral ischemia was prepared by focal middle cerebral artery occlusion, followed by 24-hour reperfusion. Then, ephrin-B2 protein was administered intracerebroventricularly for 3 consecutive days via a micro-osmotic pump. Western blot assay and quantitative real-time reverse transcription PCR demonstrated the expression levels of angiopoietin-1 （Ang-1） mRNA and protein in the penumbra cortex of the ephrin-B2 treated group were decreased at day 4 after reperfusion, and increased at day 28, while the expression levels of angiopoietin-2 （Ang-2） were highly up-regulated at all time points tested. Double immunofluorescent staining indicated that Ang-1 and Ang-2 were both expressed in vascular endothelial cells positive for CD31. These findings indicate that ephrin-B2 influences the expressions of Ang-1 and Ang-2 during angiogenesis following transient focal cerebral ischemia.展开更多
OBJECTIVE Social anxiety disorder,also known as social phobia,is the most common of all anxiety disorders.Despite the seriousness of this disorder,it has rarely been studied and as a consequence,little is known about ...OBJECTIVE Social anxiety disorder,also known as social phobia,is the most common of all anxiety disorders.Despite the seriousness of this disorder,it has rarely been studied and as a consequence,little is known about its underlying neurobiology.Growing evidence suggests that inhibitory neurons dysfunction could affect the balance of neuronal activity in psychotic disorders including anxiety,SAD,etc.Ephrin-B(EB) proteins were previously demonstrated to ensure normal distribution and function of inhibitory interneurons in the brain.We thus proposed that deletion of EB2 in inhibitory neurons might destroy the homeostasis of excitatory neurons and inhibitory neurons,and induce behavioral deficits associated with psychotic diseases.METHODS(1)Mice.We generated conditional EB2 knockout mice as a model of SAD and characterized the behaviors and the biochemical changes in the brains of the knockout mice.We also generated a mouse line with a selective deletion of EB2 from vGAT neurons by breeding a v GAT-Cre line with a loxP-flanked alleles in EB2.For EB2 detection,we crossed vGAT-Cre;EphrinB2 loxp/loxp mice with Rosa26-STOP-tdTomato Cre indicator(Ai9) mice to label the vGAT neurons with tdTomato.Mice were maintained in a mixed CD1/129 genetic background.Al experiments involving mice were carried out in accordance with the Shanghai Jiaotong University.Genotypes were unlocked only after completion of analysis.(2) General procedures for behavioral testing.Open field test:Locomotor activity was measured using an open field test.The size of the open field box was 44 cm×44 cm×44 cm.Each mouse was placed in the corner of the open-field apparatus at the beginning of the test,and allowed to explore it for 15 min.The total distance traveled(in cm) and counts for stereotyped behaviors were recorded and analyzed.The total distance traveled was used as an index of locomotor activity.The percentage of center zone entries was considered as anxiety indexes.EPM test:The elevated plus maze apparatus was made of dark gray plastic and comprised two open arms(30 cm×7 cm×0.25 cm) opposed to two enclosed arms(30 cm × 7 cm × 15 cm) elevated60 cm from the floor.Animals were placed in the central area of the apparatus with their head facing an enclosed arm(test duration,5 min).Digitized video recordings with EthoVision software were used for behavioral analysis.The percentage of time spent in open arms and the percentage of open-arm entries were calculated.Social behaviors:Briefly,a top open acrylic box was divided into three compartments by two clear acrylic glass partitions with an opening in the bottom.Wire mesh cages that are either empty or have social stimulus mouse in it were put in the center of each outer compartment.Unfamiliar naive CD1/129 mice of the same age were used as stimulus mice.Prior to the test,the mouse was introduced into the center chamber for 5 min,with both gates closed.Gates were then open and the test mouse was acclimated to explore the empty three-chambered apparatus freely for another 10 min.After the initial 15 min habituation session,mice were placed in the center compartment and allowed to explore freely all the three compartments.To examine the social contact,the following activities were recorded via a video surveillance for 10 min.The number of entries to each compartment,the time spent in each compartment as well as the time and frequency each mouse spent in sniffing were analyzed with EthoVision XT 8.5(Noldus,Wageningen,Netherlands).RESULTS(1)Social preference assays were performed in WT-vGATCre,EB2-flox,and EB2-vGATCre mice respectively.To evaluate social approach behavior,we used a three-chamber social arena to evaluate animals for their social interaction.The control groups of WTvGATCre,EB2-flox mice showed a significant preference for spending time in the social chamber(P<0.05);whereas the EB2-vGATCre mice did not show this preference and spent roughly equal time in the social and nonsocial chambers.(2)To determine if the decrease in social preference could result from changes in locomotion,we compared locomotor activity in EB2-vG ATCre mice and control mice.We did not observe a significant lower locomotive activity in mice.Hence,EB2 deletion caused a change in social preference but not in locomotion.Taken together,EB2 deletion exerts abnormal psychotogenic activity of social deficits which was often considered as an important feature of SAD.(3) The time spent in the open arms is widely used to measure anxiety in mice,with greater time spent in the open arm being considered as less anxious behavior.To normalize for individual differences in overall activity level,the time spent in the open arms was divided by the total time.The ratio was higher for WT-vGATCre mice and EB2-loxp mice as compared to the EB2-vG ATCre mice(P=0.0112,P=0.0197).Thus,results showed that there was a change in anxiety levels from in EB2-vGATCre mice as compared with control mice.CONCLUSION EB2 may be a candidate risk gene for SAD and that the EB2 conditional knockout model could be a tool for studying the underlying mechanisms in SAD.展开更多
目的研究促红细胞生成素产生肝细胞配体B2(Ephrin-B2)对抑郁症模型大鼠海马神经元细胞凋亡和氧化应激的减轻效果。方法SPF雄性SD大鼠30只,将大鼠随机分为Control组、慢性不可预见性温和应激(CUMS)组和Ephrin-B2组(10μg Ephrin-B2-可结...目的研究促红细胞生成素产生肝细胞配体B2(Ephrin-B2)对抑郁症模型大鼠海马神经元细胞凋亡和氧化应激的减轻效果。方法SPF雄性SD大鼠30只,将大鼠随机分为Control组、慢性不可预见性温和应激(CUMS)组和Ephrin-B2组(10μg Ephrin-B2-可结晶片段微渗透泵以1μl/h的速度向侧脑室注射),每组10只,后2组用CUMS建立大鼠抑郁症模型,建模21 d后,旷场实验和强迫游泳实验检测大鼠行为学变化,大鼠处死取海马组织,ELISA检测海马组织5-羟吲哚乙酸(5-HIAA)和5-羟色胺(5-HT)含量,苏木精-伊红染色、Nissl染色和TUNEL染色观察海马组织病理,Western blot检测凋亡标志物Bax、Bcl-2、半胱氨酸天冬氨酸蛋白酶3(Caspase-3)蛋白表达,试剂盒检测超氧化物歧化酶(SOD)、乳酸脱氢酶(LDH)活性和谷胱甘肽(GSH)含量,RT-PCR和Western blot分别检测沉默信息调节因子2相关酶1(SIRT1)基因和蛋白表达。结果造模后,与Control组比较,CUMS组旷场评分显著下降,水中静止时间上升,海马组织5-HIAA、5-HT含量降低(P<0.05);出现海马神经元损伤及细胞凋亡,SOD活性、GSH含量下降,LDH含量上升,Bcl-2蛋白表达降低、Bax和裂解的Caspase-3蛋白表达升高(P<0.05);SIRT1基因表达和蛋白表达明显下调(0.14±0.05 vs 1.00±0.00;0.02±0.01 vs 0.13±0.04,P<0.05)。与CUMS组比较,Ephrin-B2组上述各项指标均明显改善(P<0.05)。结论Ephrin-B2可缓解抑郁症模型大鼠神经元损伤及细胞凋亡,降低氧化应激水平,其作用可能与SIRT1表达下调有关。展开更多
Nipah Virus (NiV), a member of the Paramyxoviridae family, is one of the most infectious zoonotic viruses in Southeast Asia. First recorded in Malaysia in 1998, the NiV outbreak infected hundreds of people, with an al...Nipah Virus (NiV), a member of the Paramyxoviridae family, is one of the most infectious zoonotic viruses in Southeast Asia. First recorded in Malaysia in 1998, the NiV outbreak infected hundreds of people, with an almost 50% death rate. The virus is transmitted through direct contact with contaminated subjects and infecting the human respiratory system. Ephrin B2 and B3, the surface glycoproteins on the host cell, have been the primary and the most effective route for viral entrance. Binding with viral surface G protein, the F protein triggers, enabling viral-host fusion. Until now, NiV vaccines are not yet available in the public market, however, preventions such as avoiding direct contact and masking are advised.展开更多
文摘Ephrin-B2 has been shown to participate in angiogenesis, but the underlying mechanisms involved remain unclear. In this study, a rat model of local cerebral ischemia was prepared by focal middle cerebral artery occlusion, followed by 24-hour reperfusion. Then, ephrin-B2 protein was administered intracerebroventricularly for 3 consecutive days via a micro-osmotic pump. Western blot assay and quantitative real-time reverse transcription PCR demonstrated the expression levels of angiopoietin-1 （Ang-1） mRNA and protein in the penumbra cortex of the ephrin-B2 treated group were decreased at day 4 after reperfusion, and increased at day 28, while the expression levels of angiopoietin-2 （Ang-2） were highly up-regulated at all time points tested. Double immunofluorescent staining indicated that Ang-1 and Ang-2 were both expressed in vascular endothelial cells positive for CD31. These findings indicate that ephrin-B2 influences the expressions of Ang-1 and Ang-2 during angiogenesis following transient focal cerebral ischemia.
基金National Natural Science Foundation of China (8150115381571326).
文摘OBJECTIVE Social anxiety disorder,also known as social phobia,is the most common of all anxiety disorders.Despite the seriousness of this disorder,it has rarely been studied and as a consequence,little is known about its underlying neurobiology.Growing evidence suggests that inhibitory neurons dysfunction could affect the balance of neuronal activity in psychotic disorders including anxiety,SAD,etc.Ephrin-B(EB) proteins were previously demonstrated to ensure normal distribution and function of inhibitory interneurons in the brain.We thus proposed that deletion of EB2 in inhibitory neurons might destroy the homeostasis of excitatory neurons and inhibitory neurons,and induce behavioral deficits associated with psychotic diseases.METHODS(1)Mice.We generated conditional EB2 knockout mice as a model of SAD and characterized the behaviors and the biochemical changes in the brains of the knockout mice.We also generated a mouse line with a selective deletion of EB2 from vGAT neurons by breeding a v GAT-Cre line with a loxP-flanked alleles in EB2.For EB2 detection,we crossed vGAT-Cre;EphrinB2 loxp/loxp mice with Rosa26-STOP-tdTomato Cre indicator(Ai9) mice to label the vGAT neurons with tdTomato.Mice were maintained in a mixed CD1/129 genetic background.Al experiments involving mice were carried out in accordance with the Shanghai Jiaotong University.Genotypes were unlocked only after completion of analysis.(2) General procedures for behavioral testing.Open field test:Locomotor activity was measured using an open field test.The size of the open field box was 44 cm×44 cm×44 cm.Each mouse was placed in the corner of the open-field apparatus at the beginning of the test,and allowed to explore it for 15 min.The total distance traveled(in cm) and counts for stereotyped behaviors were recorded and analyzed.The total distance traveled was used as an index of locomotor activity.The percentage of center zone entries was considered as anxiety indexes.EPM test:The elevated plus maze apparatus was made of dark gray plastic and comprised two open arms(30 cm×7 cm×0.25 cm) opposed to two enclosed arms(30 cm × 7 cm × 15 cm) elevated60 cm from the floor.Animals were placed in the central area of the apparatus with their head facing an enclosed arm(test duration,5 min).Digitized video recordings with EthoVision software were used for behavioral analysis.The percentage of time spent in open arms and the percentage of open-arm entries were calculated.Social behaviors:Briefly,a top open acrylic box was divided into three compartments by two clear acrylic glass partitions with an opening in the bottom.Wire mesh cages that are either empty or have social stimulus mouse in it were put in the center of each outer compartment.Unfamiliar naive CD1/129 mice of the same age were used as stimulus mice.Prior to the test,the mouse was introduced into the center chamber for 5 min,with both gates closed.Gates were then open and the test mouse was acclimated to explore the empty three-chambered apparatus freely for another 10 min.After the initial 15 min habituation session,mice were placed in the center compartment and allowed to explore freely all the three compartments.To examine the social contact,the following activities were recorded via a video surveillance for 10 min.The number of entries to each compartment,the time spent in each compartment as well as the time and frequency each mouse spent in sniffing were analyzed with EthoVision XT 8.5(Noldus,Wageningen,Netherlands).RESULTS(1)Social preference assays were performed in WT-vGATCre,EB2-flox,and EB2-vGATCre mice respectively.To evaluate social approach behavior,we used a three-chamber social arena to evaluate animals for their social interaction.The control groups of WTvGATCre,EB2-flox mice showed a significant preference for spending time in the social chamber(P<0.05);whereas the EB2-vGATCre mice did not show this preference and spent roughly equal time in the social and nonsocial chambers.(2)To determine if the decrease in social preference could result from changes in locomotion,we compared locomotor activity in EB2-vG ATCre mice and control mice.We did not observe a significant lower locomotive activity in mice.Hence,EB2 deletion caused a change in social preference but not in locomotion.Taken together,EB2 deletion exerts abnormal psychotogenic activity of social deficits which was often considered as an important feature of SAD.(3) The time spent in the open arms is widely used to measure anxiety in mice,with greater time spent in the open arm being considered as less anxious behavior.To normalize for individual differences in overall activity level,the time spent in the open arms was divided by the total time.The ratio was higher for WT-vGATCre mice and EB2-loxp mice as compared to the EB2-vG ATCre mice(P=0.0112,P=0.0197).Thus,results showed that there was a change in anxiety levels from in EB2-vGATCre mice as compared with control mice.CONCLUSION EB2 may be a candidate risk gene for SAD and that the EB2 conditional knockout model could be a tool for studying the underlying mechanisms in SAD.
文摘目的研究促红细胞生成素产生肝细胞配体B2(Ephrin-B2)对抑郁症模型大鼠海马神经元细胞凋亡和氧化应激的减轻效果。方法SPF雄性SD大鼠30只,将大鼠随机分为Control组、慢性不可预见性温和应激(CUMS)组和Ephrin-B2组(10μg Ephrin-B2-可结晶片段微渗透泵以1μl/h的速度向侧脑室注射),每组10只,后2组用CUMS建立大鼠抑郁症模型,建模21 d后,旷场实验和强迫游泳实验检测大鼠行为学变化,大鼠处死取海马组织,ELISA检测海马组织5-羟吲哚乙酸(5-HIAA)和5-羟色胺(5-HT)含量,苏木精-伊红染色、Nissl染色和TUNEL染色观察海马组织病理,Western blot检测凋亡标志物Bax、Bcl-2、半胱氨酸天冬氨酸蛋白酶3(Caspase-3)蛋白表达,试剂盒检测超氧化物歧化酶(SOD)、乳酸脱氢酶(LDH)活性和谷胱甘肽(GSH)含量,RT-PCR和Western blot分别检测沉默信息调节因子2相关酶1(SIRT1)基因和蛋白表达。结果造模后,与Control组比较,CUMS组旷场评分显著下降,水中静止时间上升,海马组织5-HIAA、5-HT含量降低(P<0.05);出现海马神经元损伤及细胞凋亡,SOD活性、GSH含量下降,LDH含量上升,Bcl-2蛋白表达降低、Bax和裂解的Caspase-3蛋白表达升高(P<0.05);SIRT1基因表达和蛋白表达明显下调(0.14±0.05 vs 1.00±0.00;0.02±0.01 vs 0.13±0.04,P<0.05)。与CUMS组比较,Ephrin-B2组上述各项指标均明显改善(P<0.05)。结论Ephrin-B2可缓解抑郁症模型大鼠神经元损伤及细胞凋亡,降低氧化应激水平,其作用可能与SIRT1表达下调有关。
文摘Nipah Virus (NiV), a member of the Paramyxoviridae family, is one of the most infectious zoonotic viruses in Southeast Asia. First recorded in Malaysia in 1998, the NiV outbreak infected hundreds of people, with an almost 50% death rate. The virus is transmitted through direct contact with contaminated subjects and infecting the human respiratory system. Ephrin B2 and B3, the surface glycoproteins on the host cell, have been the primary and the most effective route for viral entrance. Binding with viral surface G protein, the F protein triggers, enabling viral-host fusion. Until now, NiV vaccines are not yet available in the public market, however, preventions such as avoiding direct contact and masking are advised.
