中国汉族人群腓骨肌萎缩症Cx32基因突变分析

Charcot Marie Tooth (CMT)diseaseisthemostcommoninheritedperipheralneuropathywithapreva lenceof 1in 2 5 0 0 .Distalmuscleweaknessandatro phy ,sensorylossandreducedorabsenttendonreflex es ,pescavus ,hammertoes ,steppagegaitareamongthemainsymptoms .Thereares…     

连接蛋白拟似肽对海人酸致痫大鼠脑电活动的影响

目的观察针对连接蛋白43(CX43)合成的特异性的缝隙连接阻断剂-连接蛋白拟似肽对海人酸致痫大鼠脑电活动的影响。方法建立18只大鼠癫痫动物模型,分连接蛋白拟似肽组、甘珀酸组和对照组(每组6只),在在体上分别局部给予连接蛋白似似肽、甘珀酸和生理盐水,用脑电图仪观测用药前后每组大鼠皮层脑电活动的变化情况。结果连接蛋白拟似肽组及甘珀酸组给药后癫痫的发作次数明显比给药前发作次数减少,癫痫波的平均振幅也明显变小,给药前后比较有显著性差异(P<0.01),生理盐水组给药前后癫痫的发作次数及平均振幅几乎没有变化。连接蛋白拟似肽组给药前后癫痫的发作次数和波幅的变化值与甘珀酸组给药前后癫痫的发作次数和波幅的变化值相比无显著性差异。结论针对CX43合成的连接蛋白拟似肽可以特异性地抑制癫痫的发作。     

oxLDL对人脐静脉内皮细胞通透性影响及机制研究

目的探讨氧化低密度脂蛋白（ox LDL）对人脐静脉内皮细胞（HUVECs）通透性的影响及其可能机制。方法采用Transwell单层细胞模型系统和油红O染色,观察ox LDL对单层血管内皮细胞通透性的影响以及THP-1巨噬细胞内脂质的蓄积情况;采用蛋白质印迹法及免疫荧光技术检测ox LDL对HUVECs紧密连接occludin蛋白的表达及分布改变。结果 ox LDL增加单层内皮细胞对LDL的通透性和THP-1巨噬细胞脂质的蓄积;ox LDL降低occludin蛋白的表达,同时免疫荧光染色显示,ox LDL处理后,血管内皮细胞间隙增宽,occludin染色减少或脱失,而抑制氧化应激可以减弱ox LDL对内皮细胞的高通透性反应和occludin蛋白表达和形态学的影响。结论 ox LDL可能是通过occludin蛋白表达下降使内皮细胞构改变来介导内皮通透性增加,从而促进内皮下巨噬细胞内的脂质蓄积。     

肺泡中性粒细胞凋亡与occludin蛋白改变在胆道梗阻大鼠肺损伤中的作用

目的：观察胆道梗阻（BDO）大鼠支气管肺泡灌洗液（BALF）中性粒细胞（PMN）凋亡情况与肺泡上皮细胞occludin蛋白变化,分析两者与梗阻性黄疸肺损伤的关系。 方法：72只SD大鼠,随机抽取8只作为正常对照组,将另64只大鼠随机均分为假手术组和模型组;假手术组大鼠行假手术,模型组大鼠行胆总管双重结扎建立BDO模型。假手术组与模型组大鼠于术后3、7、10、14 d分批等量（n=8）处死,留取标本;正常对照组则在实验期间随机处死获取标本。检测大鼠肺组织形态学、BALF中PMN凋亡率和MMP-9活性,肺组织occludin蛋白,并计算肺通透指数（LPI）。 结果：与正常对照组比较,假手术组各项指标在各时间点均无明显差异,定量指标间差异均无统计学意义（均P>0.05）。模型组肺组织出现明显的病理改变,且与假手术组比较,BALF中PMN凋亡率逐渐减少,MMP-9活性逐渐增高,3~14 d各时间点差异均有统计意义（均P<0.05）;肺组织occludin蛋白逐渐减少,LPI逐渐增加,在7~14 d各时间点差异均有统计意义（均P<0.05）。相关性分析显示,BDO大鼠PMN凋亡率与MMP-9活性呈负相关（r=-0.935）,MMP-9活性与肺组织occludin蛋白水平呈负相关（r=-0.796）,肺组织occludin蛋白水平与LPI呈负相关（r=-0.800）（均P<0.05）。 结论：BDO大鼠肺泡PMN凋亡减少、MMP-9活性增强,从而引起occludin蛋白减少,造成肺泡上皮屏障损伤、通透性增加,该病理过程在梗阻性黄疸肺损伤的发生发展中可能发挥了重要作用。     

Cell-to-cell communication and expression of gap junctional proteins in human diabetic and nondiabetic skin fibroblasts

Wound healing involves the interactions of many cell types, and is controlled in part by growth factors. Intercellular communication mediated by gap junctions is considered to play an important role in the coordination of cellular metabolism during the growth and development of tissues and organs. Basic fibroblast growth factor (bFGF), known to be important in wound healing, has been found to increase Cx43 expression and intercellular communication in endothelial cells and cardiac fibroblasts. It has been proposed that an increased coupling is necessary for the coordination of these cells in wound healing and angiogenesis, and that one of the actions of bFGF is to modulate intercellular communication. The aim of our study was to evaluate the effects of bFGF on gap junctional intercellular communication (GJIC) in vitro, and the presence of gap junctional proteins connexin (Cx) 26, Cx32, and Cx43 in fibroblasts of diabetic and nondiabetic individuals. Fibroblast cell lines (n=10) were cultured for 3 d in serum-free media with or without bFGF (3 ng/mL). Cells were evaluated for the rate of GJIC by using laser cytometry, and for the presence of Cx26, Cx32, and Cx43 by immunohistochemical and Western analyses. All cell types communicated via contact-dependent mechanisms. The rate of GJIC was greater (p<0.01) for diabetic than for nondiabetic fibroblasts (4.1±0.01 vs 3.3±0.01 %/min). bFGF increased (p<0.01) the rate of GJIC for diabetic (4.9±0.01 vs 4.1±0.01%) and nondiabetic (4.1±0.01 vs 3.3±0.01%) fibroblasts. Immunohistochemistry identified Cx26 in the cytoplasm, Cx32 was not detected, and Cx43 was present on the cellular borders in all cultures. Image analysis of immunofluorescent staining demonstrated that bFGF increased (p<0.05) Cx43 expression in diabetic and nondiabetic fibroblasts. Western immunoblot analysis revealed bands at 43–46 kD that were similar in volume for diabetic and nondiabetic fibroblasts. Thus, gap junctions involving Cx43 and GJIC among fibroblasts appear to be targets for bFGF. Fibroblasts of diabetic individuals appear to have an increased rate of cell-cell coupling, correlating with a decreased rate of proliferation.     

渗透压变化对缝隙连接蛋白在培养的大鼠下丘脑星形胶质细胞和神经元表达的影响

目的观察渗透压改变对培养的下丘脑星形胶质细胞的缝隙连接蛋白Connexin43（Cx43）和神经元的缝隙连接蛋白Cx32表达的影响。方法体外培养孕14d或新生1d SD大鼠下丘脑的神经元和星形胶质细胞并进行纯化和鉴定。实验各分两组,第1组：细胞由等渗培养液移至高渗培养液（含9％NaCl）分别放置1min、3min、5min、10min和15min后将液体吸出常规固定;第2组：细胞先置于高渗培养液中15min后换成等渗培养液,分别在1min、3min、5min和10min后将等渗培养液吸出常规固定。两者均进行抗Cx43或抗Cx32的免疫荧光染色,Confoeal显微镜观察。结果第1组,Cx43在刺激1min后在星形胶质细胞表达比对照组有所增加,3min达到高峰,以后逐渐降低,15min恢复正常;而Cx32在刺激后1min的神经元中表达比对照组增加,5min达到高峰,以后降低。15min恢复正常。第2组同样为Cx43在星形胶质细胞刺激1min后表达增加,3min达到高峰,以后降低,10min恢复正常;神经元的Cx32表达在刺激后5min达到高峰,以后降低,10min恢复正常。两组Cx43表达的高峰期均早于Cx32。结论Cx43和Cx32可能参与星形胶质细胞与神经元渗透压的调节。     

益生菌VSL#3对实验性结肠炎大鼠结肠黏膜Claudins蛋白表达的影响

目的 观察益生菌VSL#3对2,4,6-三硝基苯磺酸(TNBS)诱导的大鼠急性结肠炎的保护作用,以及对紧密连接蛋白Claudins（Claudin-1,-2,-3）在结肠黏膜上表达的影响。方法 24只健康雌性SD大鼠采用TNBS一次性灌肠法建立大鼠结肠炎模型,造模完成后第2天开始,8只大鼠每日给予2ml0.9％ NaC1溶液灌胃（TNBS组）,8只给予100 mg VSL#3（VSL#3组）,另8只给予200 mg 5-氨基水杨酸(5-ASA)灌胃（5-ASA组）。5只同级别未造模大鼠作为对照组每日给予0.9％ NaCl溶液灌胃,均持续1周并处死。处死时留取粪便标本并做细菌培养以检测肠道菌群的变化。通过观察腹泻、便血和体重情况计算疾病活动指数(DAI)。取结肠组织做HE染色,观察病理学改变;酶联免疫吸附试验(ELISA)检测肠组织髓过氧化物酶(MPO)的变化;量子点免疫荧光标记法检测Claudins在结肠黏膜的表达和分布。结果 与TNBS组比较,益生菌VSL#3和5-ASA治疗均能降低结肠炎大鼠明显升高的DAI和肠组织MPO水平,减轻结肠炎性反应评分。与对照组比较,结肠炎大鼠的肠道细菌计数发生改变,Claudin-1,-2,-3蛋白表达均明显增加（平均荧光强度分别为66.200±5.737、71.780±6.670、61:300土5.199,t值分别＝17.237、27.909和21.788;P值均＜0.01）;而与TNBS组和5-ASA组比较,VSL#3可调节肠道菌群平衡,增加Claudin-1,-3的表达（Claudin-1:75.550±8.717比66.200±5.737和67.080±5.401;t＝9.348,8.469;P值均＜0.05;Claudin-3:68.820±7.443比61.300土5.199和59.830±5.930;t＝7.519,8.988,P值均＜0.05),降低Claudin-2的表达(58.740±6.457比71.780±6.670和66.870±5.791;t＝13.033,P＜0.01;t＝8.123,P＜0.05)。结论 益生菌VSL#3可能通过改变Claudins蛋白的表达,增强肠黏膜屏障功能,从而发挥缓解急性结肠炎性反应的作用。     

间隙连接蛋白43与胎膜早破的相关性

胎膜早破(premature rupture of membranes,PROM)是产科最常见的早产原因之一,可诱发新生儿呼吸窘迫综合征、绒毛膜羊膜炎、胎盘早剥、败血症等不良结局.间隙连接通讯是细胞间最常见的信息交互及物质交换途径,其功能主要由间隙连接蛋白实现,间隙连接蛋白43(Connexin43,Cx43)是间隙连...     

连接蛋白40/43调节大鼠血管平滑肌细胞内钙离子浓度与肠系膜上动收缩反应性的研究

目的 了解连接蛋白40(Cx40)/43调节失血性休克大鼠肠系膜上动脉(SMA)内膜依赖的血管收缩反应性,探讨与血管平滑肌细胞(VSMC)胞内钙离子浓度([Ca2+]i)的关系.方法 以传至3～5代培养的SD大鼠血管内皮细胞(VEC)及VSMC为研究对象,观察不同程度缺氧对SMA和VSMC收缩反应性的影响;用Cx40/43的反义寡脱氧核苷酸(ASODN)阻断SMA、VEC和VSMC的Cx40/43表达,观察Cx40/43对缺氧SMA的收缩反应性和VSMC[Ca2+]i的作用.结果 缺氧后SMA和VSMC的收缩反应性均呈先增加后降低的变化过程;缺氧可以引起VSMC钙超载,[Ca+]i从常氧状态下的(82±4)%增至缺氧30 min时的(115±8)%和缺氧2 h的(133±13)%;Cx40 ASODN可以增加VSMC的[Ca+]i和SMA对杨梅黄酮的收缩反应性,Cx43 ASODN则引起相反效应.结论 Cx40/43通过调节VSMC[Ca+]i,间接参与调节休克后SMA内膜依赖的血管收缩反应性.