Foxa2基因在NIPBL^+/-基因缺陷小鼠心脏房间隔缺损表达分析

Expression analysis of Foxa 2 gene in NIPBL^+/-deficient mice with cardiac atrial septal defect

目的德朗综合征出现房间隔缺损在以往的研究中较少,文章通过研究Foxa2基因在心脏组织的表达,探讨NIPBL+/-小鼠模型中房间隔缺损的形成与Foxa 2基因表达关系。方法以NIPBL+/-小鼠为实验组,野生型NIPBL+/+小鼠为正常组,每组6只,分别测量小鼠1、2、3、4周时体重,记录数据。并在4周取小鼠心脏组织,采用实时荧光定量PCR(qRT-PCR)法、Western blot法分别检测Foxa 2基因水平以及蛋白水平表达。制作病理切片、HE染色,观察NIPBL基因缺陷对小鼠心脏发育变化的影响,以及心脏房间隔处的解剖结构。结果实验组小鼠在1、2、3、4周4个时间点的体重均低于正常组(P<0.05)。PCR检测表明,4周时正常组小鼠心脏房间隔处组织的Foxa2 mRNA的表达(9.23±1.22)明显高于实验组(5.87±1.42),差异有统计学意义(P<0.05)。Western blot检验结果显示,实验组小鼠4周时心肌细胞中Foxa2蛋白的表达量较对照组Foxa2蛋白的表达明显降低(P<0.05)。HE染色显示观察4周时正常组与实验组小鼠心脏解剖结构,发现NIPBL+/-基因缺陷小鼠的对照组小鼠心脏房间隔存在明显缺损。结论NIPBL+/-基因缺陷鼠心脏组织中Foxa 2基因表达降低,可能是导致小鼠生长发育迟缓,体重下降的影响因素。NIPBL+/-基因缺陷小鼠心脏房间隔处异常缺损可能与小鼠的NIPBL基因存在缺陷下调Foxa2基因在心肌细胞表达有关。

Objective The occurrence of atrial septal defect in Cornelia DE Lange syndrome are rarely reported in previous studies.The objective of this study is to investigate the relationship between the formation of atrial septal defect and Foxa2 gene expression in NIPBL+/-mouse model through the analysis of the expression of Foxa2 gene in heart tissue.Methods The NIPBL+/-mice were used as the experimental group,and wild-type NIPBL+/+mice were used as the normal group.There were six mice in each group.The weights of the mice at 1,2,3,and 4 weeks were measured and recorded.Mouse heart tissues were collected at 4 weeks,and the expression of Foxa2 gene and protein were determined by real-time fluorescence quantitative PCR(Qrt-PCR)and Western blot.Pathological sections and HE staining were carried out to observe the effect of NIPBL gene defect on the development and changes of the mouse heart,as well as the anatomical structure of the atrial septum of the heart.Results The weight of mice in the experimental group was significantly lower than that of the normal group(P<0.05)at all four time points.Foxa2 gene expression and protein expression in heart tissues of the experimental group were statistically lower than those of the normal group(P<0.05).Abnormal defect was observed in the atrial septum of the heart pathological sections of the NIPBL deficient mice.Conclusion The decreased expression of Foxa2 gene in the heart tissue of NIPBL+/-deficient mice may be a factor inducing growth retardation and weight loss in mice.The abnormal defect in the atrial septum of nipbl-deficient mice might be associated with the down-regulation of Foxa2 gene expression in cardiomyocytes.