Nrf2敲除小鼠模型的构建与基因型鉴定

目的 构建并鉴定Nrf2敲除模型小鼠。方法 将引进一对雌雄杂合子(Nrf2^-/+)小鼠进行交配,繁育出F1代小鼠;将F1代小鼠中基因型为Nrf2^-/+的雌雄小鼠继续进行交配,获得F2代小鼠;小鼠5日龄时剪尾部组织提取DNA,用PCR和琼脂糖凝胶电泳进行基因型结果判定。提取Nrf2敲除小鼠肺组织蛋白质,用Western blot检测NRF2蛋白表达情况,佐证鉴定结果。结果 雌雄纯合子(Nrf2^-/-)基因敲除小鼠可继续交配,获得基因敲除纯合子小鼠;F1与F2代杂合子小鼠交配可获得3种基因型：野生型(Nrf2^+/+)、杂合子(Nrf2^+/-)、纯合子(Nrf2^-/-),用PCR成功鉴定出子代小鼠的基因型;Nrf2敲除小鼠肺组织的NRF2蛋白表达显著低于野生型(P<0.05)。结论 本研究成功繁育出Nrf2全身敲除模型小鼠,为进一步探讨NRF2的作用及其机制提供了新的实验工具。     

糖基因GLT25D1和GLT25D2缺失对APAP诱导的急性药物性肝损伤的影响

目的 研究糖基因Glt25D1和Glt25D2在对乙酰氨基酚(acetaminophen,APAP)诱导的急性药物性肝损伤中的可能作用及机制.方法 抽取6～8周雄性糖基因Glt25D1和Glt25D2敲除小鼠(Glt25D1Δhep Glt25D2-/-)及野生型小鼠(Wild type,WT),构建药物性肝损伤模型....     

糖基因Glt8d2重组蛋白的表达、纯化及多克隆抗体的制备

目的 构建新糖基转移酶基因Glt8d2的原核表达载体,诱导融合蛋白的表达,并对其进行纯化;制备兔抗Glt8d2蛋白多克隆抗体并进行鉴定.方法 应用RT-PCR技术,以HepG2细胞mRNA为模板,扩增Glt8d2目的基因片段,构建原核表达载体pET-32a(+)-Glt8d2.转化大肠埃希菌BL21,异丙基-D-半乳糖...     

敲除Colgalt2基因加重小鼠急性肝损伤

目的：初步探讨Colgalt2基因介导的胶原Glcα1,2 Galβ1?糖基化修饰在急性肝损伤过程中的作用。方法取60只Colgalt2＋／＋小鼠和60只Colgalt2－／－小鼠进行急性肝损伤实验,雌雄各半。每组随机选取20只小鼠腹腔注射CCl4（CCl4∶橄榄油＝2∶7,20 ml／kg）。观察小鼠死亡情况,并绘制生存曲线。每组剩余40只小鼠随机分为0、4、8、12 h组,每组10只,腹腔注射CCl4（剂量同上）。分别于0、4及8 h各处死6只小鼠,之后将4及8 h组剩余的小鼠均纳入12 h组（ Colgalt2＋／＋小鼠, n＝14; Colgalt2－／－小鼠, n＝16）,并于12 h处死小鼠。 HE染色观察肝组织的病理学改变,取血清进行生化指标ALT、 AST测定。利用qRT?PCR和Western印迹技术检测小鼠Colgalt2在基因及蛋白水平的表达情况。结果Colgalt2基因在Col?galt2＋／＋小鼠肝组织内表达,而在Colgalt2－／－小鼠肝组织内不表达。注射CCl4后10 h, Colgalt2＋／＋小鼠死亡率为35％, Colgalt2－／－小鼠死亡率为70％,两组小鼠死亡率差异显著（P＜0．05）。注射CCl4后12 h, Colgalt2＋／＋小鼠死亡率达50％, Colgalt2－／－小鼠死亡率为70％,差异不显著（P＞0．05）。肝功检测及HE染色结果均提示,与Colgalt2＋／＋小鼠相比, Colgalt2－／－小鼠肝损伤较重。注射CCl4后,野生型小鼠Colgalt2在RNA水平和蛋白水平表达下调。结论 Colgalt2基因敲除在一定程度上可加重小鼠急性肝损伤。该观察结果提示, Colgalt2基因介导的胶原Glcα1,2 Galβ1?糖基化修饰可能与肝损伤的修复有关。     

FGFR2基因敲除小鼠模型的应用

FGFR2基因与人类多种疾病密切相关。随着小鼠遗传工程技术的发展,利用基因敲除、转基因小鼠模型来研究基因与人类疾病的关系,已成为人们研究的热点。本文综述了FGFR2基因敲除小鼠模型近年来的研究近展,对几种FGFR2相关的基因敲除小鼠模型进行了系统的分类归纳,讨论了其在组织器官发育和相关人类疾病机制研究中的应用,并展望了其发展前景。     

Smad3基因敲除小鼠肾Smad2和p-Smad2表达的变化

目的:观察Smad3基因敲除小鼠肾Smad2和p-Smad2表达的变化,探讨Smad3基因敲除小鼠肾是否有Smad2和p-Smad2代偿性增加.方法:4只Smad3基因敲除小鼠,10只野生型小鼠,应用免疫组织化学显色技术,检测Smad2和p-Smad2蛋白的定位和表达情况,并用Motic病理图像分析系统对图像进行半定量分析.结果:野生型小鼠肾Smad2蛋白在肾远端小管和肾集合管细胞胞质中有广泛弱表达,p-Smad2蛋白在肾远端小管和肾集合管细胞胞质、胞核中也有弱表达,而Smad3基因敲除小鼠的Smad2和p-Smad2的表达比野生型小鼠有显著升高.结论:Smad3基因敲除能引起小鼠肾Smad2和p-Smad2表达的代偿性增加.     

利用CRISPR/Cas9技术制备成对框基因2敲除小鼠

目的 利用成簇规律间隔短回文重复序列（CRISPR）/重组CRISPR相关核酸酶9（Cas9）技术双切口法制备成对框基因2（Pax2）敲除小鼠,为探讨Pax2基因在多个系统发育的作用提供动物模型。方法 根据Pax2基因序列设计sgRNA,设计出的sgRNA和Cas9体外转录后显微注射到C57BL/6J 小鼠的受精卵中,F0代小鼠出生后取其基因DNA测序鉴定基因型。共获得8只F0 代小鼠,使敲除成功的F0代小鼠与野生C57BL/6J 小鼠交配,获得F1代小鼠,后均采用基因成功敲除的小鼠与C57BL/6J 小鼠进行交配,可获得稳定的Pax2基因敲除小鼠。结果 成功获得可稳定繁殖的Pax2杂合子基因敲除小鼠,其Pax2基因缺失1628 bp;组织HE染色显示,敲除小鼠的肾小球数量明显减少;Western blotting结果显示,敲除小鼠的肾皮质Pax2蛋白表达较野生型小鼠减少。结论 利用CRISPR/Cas9技术可成功构建Pax2杂合子基因敲除小鼠,为进一步研究Pax2基因的作用奠定基础。     

H-2Kb基因转移诱导小鼠心肌移植免疫耐受

目的探讨H-2Kb基因转移诱导小鼠心肌移植免疫耐受的可行性。方法通过逆转录病毒载体介导的基因转移技术,将供体小鼠(C57BL/6)的H-2Kb基因(小鼠MHC-类基因)导入到受体小鼠(BALB/c)的造血细胞。结果H-2Kb基因可以稳定地整合进小鼠造血细胞的基因内,并在受体内表达较长时间。正常对照小鼠的心肌移植物平均存活时间(MST)为9.4±1.84d。诱导耐受组小鼠的心肌移植物MST为45.7±6.001d,比对照组明显延长(P<0.05)。结论H-2Kb基因转移诱导了供体特异性的免疫耐受,为临床移植控制排斥反应提供了一种新的方法     

肝脏特异性DEK基因敲除小鼠模型的制备及鉴定

目的　利用Cre/loxp基因敲除技术构建肝脏特异性DEK基因敲除小鼠,为研究DEK基因在肝脏中的生物学功能提供重要动物模型。 方法　将DEKflox/flox小鼠与肝脏特异性表达Alb-Cre重组酶的小鼠进行交配和鉴定,筛选出子代中DEKflox/+/Alb-Cre小鼠与DEKflox/flox小鼠进行交配与鉴定,获得DEKflox/flox/Alb-Cre小鼠,将DEKflox/flox/Alb-Cre小鼠与DEKflox/flox小鼠进行交配,其子代基因型为DEKflox/flox/Alb-Cre的小鼠即为本实验所构建的肝脏特异性DEK基因敲除小鼠,DEKflox/flox小鼠即为对照小鼠。提取小鼠尾基因组DNA,通过PCR鉴定子代小鼠的基因型;提取小鼠肝脏RNA和总蛋白,利用Real-Time PCR和Western Blotting技术检验DEK基因在小鼠肝脏中的mRNA水平和蛋白质水平的表达情况,使用激光共聚焦检测DEK蛋白在小鼠肝脏的表达情况;对小鼠肝脏行苏木精-伊红染色观察小鼠肝组织的形态学变化。 结果　PCR结果表明子代小鼠基因型符合DEKflox/flox/Alb-Cre;肝脏特异性DEK基因敲除小鼠肝组织中DEK基因的mRNA水平及蛋白质水平显著低于DEKflox/flox型小鼠;肝脏特异性DEK基因敲除小鼠肝组织的形态学特征与对照组小鼠相比无明显差异。 结论　本研究利用Cre/Loxp技术成功构建了肝脏特异性DEK基因敲除小鼠,为在动物水平进一步研究DEK基因的作用提供了重要动物模型。     

CTNND2基因敲除对小鼠学习记忆的影响

目的:探讨连环蛋白δ2(CTNND2)基因敲除对小鼠学习记忆功能的影响及可能机制.方法:聚合酶链式反应(PCR)验证野生型(WT)和CTNND2--两组小鼠基因型.Morris水迷宫检测两组小鼠空间学习记忆功能.高尔基染色法检测两组小鼠海马区神经元树突棘密度的变化.Western Blot检测两组小鼠海马突触相关蛋白磷...     

乳猪肝胶原水解物的制备及其对荷瘤小鼠肿瘤生长影响的实验研究

目的:从乳猪肝中提取可溶性胶原,经水解后制备肝胶原水解物(HCH),观察其对荷瘤小鼠S180纤维肉瘤和HepA肝瘤增殖的影响。方法:从乳猪肝中用生化方法提取可溶性胶原,经胃蛋白酶水解制备HCH;采用SDS-PAGE电泳和激光飞行时间质谱测定其分子量。设立生理盐水阴性对照和阿霉素阳性对照组,观察HCH对荷瘤昆明小鼠S180纤维肉瘤和HepA肝瘤增殖的影响。结果:电泳结果显示,HCH的分子量范围为3.494~8.702kD,质谱结果显示,其分子量为2.313~8.809kD。其对荷瘤小鼠S180纤维肉瘤生长的抑制呈剂量相关性,25、50、100mg·kg^-1·d^-1的抑制率为53.87%、76.53%、58.20%,而阿霉素(2mg·kg^-1·d^-1)阳性对照组的抑制率为62.41%;HCH能剂量依赖性地抑制HepA肝瘤生长,25、50、100、200mg·kg^-1·d-1的抑制率为43.26%、55.06%、74.71%、40.47%。结论:经此方法制备HCH,其分子量在2~9kDa之间,能抑制荷瘤小鼠肿瘤的生长。     

Antifibrotic effects of crocetin in scleroderma fibroblasts and in bleomycin-induced sclerotic mice

OBJECTIVE:

To investigate the antifibrotic effects of crocetin in scleroderma fibroblasts and in sclerotic mice.

METHODS:

Skin fibroblasts that were isolated from three systemic scleroderma (SSc) patients and three healthy subjects were treated with crocetin (0.1, 1 or 10 μM). Cell proliferation was measured with an MTT assay. Alpha-smooth muscle actin was detected via an immunohistochemical method. Alpha 1 (I) procollagen (COL1A1), alpha 1 (III) procollagen (COL3A1), matrix metalloproteinase (MMP)-1 and tissue inhibitor of matrix metalloproteinase (TIMP)-1 mRNA levels were measured using real-time PCR. SSc mice were established by the subcutaneous injection of bleomycin. Crocetin (50 mg/kg/d) was injected intraperitoneally for 14 days. Dermal thickness and lung fibrosis were assessed with Masson''s trichrome staining. Plasma ET-1 was detected with an enzyme-linked immunosorbent assay (ELISA). Skin and lung ET-1 and COL1A1 mRNA levels were measured via real-time PCR.

RESULTS:

Crocetin inhibited the proliferation of SSc and normal fibroblasts, an effect that increased with crocetin concentration and incubation time. Crocetin decreased the expression of α-SMA and the levels of mRNA for COL1A1, COL3A1 and matrix metalloproteinase-1, while crocetin increased TIMP-1 mRNA levels in both SSc and normal fibroblasts. Skin and lung fibrosis was induced, and the levels of ET-1 in the plasma, skin and lungs were elevated in bleomycin-injected mice. Crocetin alleviated the thickening of the dermis and lung fibrosis; decreased COL1A1 mRNA levels in the skin and lung; and simultaneously decreased ET-1 concentrations in the plasma and ET-1 mRNA levels in the skin and lungs of the bleomycin-induced sclerotic mice, especially during the early phase (weeks 1-3).

CONCLUSION:

Crocetin inhibits cell proliferation, differentiation and collagen production in SSc fibroblasts. Crocetin alleviates skin and lung fibrosis in a bleomycin-induced SSc mouse model, in part due to a reduction in ET-1.     

Beta-2 glycoprotein I and its role in antiphospholipid syndrome-lessons from knockout mice

The antiphospholipid syndrome is characterized by the presence in serum of autoantibodies against beta2GPI. Although the role of beta2GPI in the pathogenesis of antiphospholipid antibody syndrome (APS) is well recognized, its exact physiological functions still remain undisclosed. Several interactions of beta2GPI with components of the coagulation cascade have been proposed, resulting in both procoagulant and anticoagulant effects. Additionally, beta2GPI has been implicated in the mechanism of recurrent fetal loss entailed in APS. Recently, using a homologous recombination approach, reproduction of mice homozygous for deletion of the beta2GPI gene has been feasible. beta2GPI knockout mice offer a valuable tool for revealing the physiological role of the protein. These mice show decreased in vitro ability for thrombin generation. Furthermore, although mice lacking beta2GPI are fertile, the success of early pregnancy is moderately compromised and functional beta2GPI is believed necessary for optimal implantation and placental morphogenesis.     

清道夫受体AⅠ/Ⅱ对小鼠脂质代谢的影响

目的:鉴定清道夫受体AⅠ/Ⅱ(SR-AⅠ/Ⅱ)基因敲除小鼠, 观察SR-AⅠ/Ⅱ基因敲除对小鼠脂质代谢的影响。方法:应用SR-AⅠ/ⅡcDNA基因部分序列作探针, 用Southernblot方法检测SR-AⅠ/Ⅱ基因敲除小鼠及其同系对照小鼠靶基因敲除结果, 用生化分析仪检测血脂、载脂蛋白和血肌酐, 观察SR-AⅠ/Ⅱ基因敲除和未敲除小鼠分别在普通饮食和高脂饮食情况下脂质代谢的改变情况。结果:SR-AⅠ/Ⅱ基因敲除后小鼠的低密度脂蛋白(LDL)、体重较正常对照小鼠明显增高(P<005), 出现了脂质代谢严重失衡, 在高脂饮食情况下这种失衡更为明显, 体重、LDL的升高幅度均大于对照组(P<0.01).结论:SR-AⅠ/Ⅱ参与对组织和循环中的LDL的摄取和清除, 有利于保持机体脂质代谢的正常调节。小鼠SR-AⅠ/Ⅱ基因敲除后脂质代谢发生了明显紊乱, 机体对脂质代谢的调节功能减弱。     

Interaction of neonatal irradiation and single-genes upon growth and behavior in mice

Postnatal growth and behavior following neonatal irradiation were studied in congenic strains of mice. Mice were genetically similar except for single-gene substitutions at either the steel or dominant spotting loci. Adult behavior was measured by locomotion and elimination in the open field and by spontaneous activity in exercise wheels. In general, neonatal irradiation caused a decrease in body weight, activity in exercise wheels, and elimination in the open field, but an increase in locomotion in the open field. Significant differences due to genotype and sex were observed for locomotion and body weight. Differential responses of the genotypes to neonatal irradiation were observed in body weight and in activity in exercise wheels. The genotypes, in order of increasing sensitivity, were +/+, W^a/+, and Sl^gb/+.     

Gastric acid secretion in cholecystokinin-1 receptor, -2 receptor,and -1, -2 receptor gene knockout mice

Gastrin is important for stimulating acid secretion as well as differentiating gastric mucosal cells via cholecystokinin-2 receptors (CCK-2Rs). In turn, CCK acts preferably via CCK-1R to release somatostatin, and somatostatin has been postulated to exhibit a tonic inhibition of gastrin bioactivity. The present study was designed to examine the hypothesis that CCK-1R and 2R may act in opposite directions in gastric acid secretion. Having generated CCK-1R(−/−), 2R(−/−), and 1R(−/−)2R(−/−) mice, we examined the regulation of gastric acid secretion in four genotypes including wild-type mice. Parietal cells possess histamine receptors, muscarinic receptors, and CCK-2Rs. Since histamine increases cAMP and carbachol increases calcium, the responses of gastric acid secretion to graded doses of histamine, carbachol, and a combination of histamine + carbachol were determined. The sensitivity to histamine did not differ among the four genotypes, while the maximal acid secretion was lower in CCK-2R(−/−) mice than in wild-type mice. In addition, sensitivity to carbachol was impaired in mice without CCK-2R. The interaction of histamine and carbachol was conserved in all genotypes. In conclusion, CCK-2R is necessary to respond to carbachol as well as to produce the maximal acid secretion, while the role of CCK-1R in acid secretion is less important.     

利用基因敲除小鼠研究发热机制的进展

Increasing evidence suggests that a complex net-work of fever induction pathways in mammalian exists.In this article,the overview of recent studies on the mechanism of fever induced by different pyrogens using IL-1,IL-1R,ICE,IL-1ra,IL-1RacP,IL-6,IL-10,TNFR,cPLA2,COX,EP,AT2,iNOS and D2/3 knockout mice is presented.Hyperthermia respond to localized infection/inflammation(e.g.,scinjection of turpentine) is mediated by IL-1β and IL-6 in turn.While fever induced by systemic infection/inflammation(e.g.,treatment with LPS intraperitoneally)varies with the different doses of pyrogens administered.Fever caused by a low dose of LPS administered ip is IL-6 dependent,but the IL-6 independent pathway is crucial for the fever evoked by a high dose of LPS.Febrile responses during both local and systemic infection/inflammation develop totally through central PGE2 dependent mechanism,but some stress induced hyperthermia otherwise.     

心肌组织特异性高表达核仁素转基因小鼠的构建与鉴定

 目的：构建并鉴定心肌组织特异性高表达核仁素(Ncl)的转基因小鼠,为从整体水平上研究核仁素对心肌功能的影响及其发挥心肌保护作用的机制提供动物模型。方法：采用基因重组法将小鼠核仁素基因的全长cDNA插入含心肌细胞特异性启动子的Alpha-MyHC clone 26载体,构建Alpha-MyHC clone 26-Ncl重组载体,通过双酶切及基因测序鉴定其正确性;采用PCR鉴定阳性小鼠并用Western blotting法观察转基因小鼠中核仁素的表达情况,采用组织切片及HE染色法观察转基因小鼠心肌组织形态;测量心脏重量指数和左室压最大上升速率,观察核仁素在心肌组织高表达后对小鼠心脏形态功能是否有影响。结果：PCR法观察显示获得4只阳性小鼠(51、52、56和86,其中52和86系繁殖良好）,Western blotting结果表明转基因小鼠的核仁素表达量明显高于野生鼠,HE染色等结果表明核仁素对心肌形态学、心脏/体重比值及心功能无明显影响。结论：成功制备了心肌组织特异性高表达核仁素的转基因小鼠,与野生型小鼠相比,转基因小鼠心肌形态及心功能无明显差异。