敲除NIPBL基因可下调小鼠骨髓间充质干细胞增殖及成骨分化能力

文题释义：NIPBL基因：其编码的蛋白Delangin通过调控cohesin蛋白加载到DNA上，所以又名粘连蛋白加载因子(cohesin loading factor)。它还能调控多个基因的表达，也与基因修复有关。在研究德朗热综合征致病机制过程中，NIPBL基因最受人关注。德朗热综合征：是以身材矮小、骨骼发育、智力低下和特殊面容为主要特征的遗传性疾病，患病率为1∶10 000- 1∶30 000，它的发病机制主要与7个基因(NIPBL、SMC1A、SMC3、BRD4、HDAC8、RAD21、ANKRD11)突变密切相关，确定NIPBL基因是否突变在德朗热综合征诊断中被作为首要检测指标。背景：德朗热综合征是一种多系统发育缺陷的遗传性疾病，NIPBL是其主要致病基因。目的：探讨NIPBL基因对骨髓间充质干细胞增殖及成骨分化能力的影响。方法：采用NIPBL-Loxp小鼠与Cre小鼠构建NIPBL基因缺陷杂合子小鼠模型(NIPBL^+/-)并将其作为实验组，野生型(NIPBL^+/+)小鼠作为对照组，分离培养两组小鼠骨髓间充质干细胞，传至第3代时采用CCK-8法比较两组细胞增殖能力，然后进行成骨诱导培养比较两组细胞成骨分化能力。结果与结论：①实验组骨髓间充质干细胞的增殖能力低于对照组(P <0.05)；②成骨诱导第7天，实验组细胞碱性磷酸酶活力明显低于对照组(P <0.05)；③成骨诱导后，实验组Runx2、OCN基因及其蛋白的表达水平低于对照组(P <0.05)；④成骨诱导第21天，茜素红染色后倒置显微镜下观察对照组较实验组可见更多的红色钙结节；⑤结果提示，敲除NIPBL基因降低了骨髓间充质干细胞的增殖、成骨分化能力。ORCID: 0000-0001-7493-4402(林明)中国组织工程研究杂志出版内容重点：干细胞；骨髓干细胞；造血干细胞；脂肪干细胞；肿瘤干细胞；胚胎干细胞；脐带脐血干细胞；干细胞诱导；干细胞分化；组织工程

Knockout of NIPBL gene down-regulates the abilities of proliferation and osteogenic differentiation in mouse bone marrow mesenchymal stem cells

BACKGROUND:Cornelia de Lange syndrome is a genetic disease with multiple developmental defects,of which NIPBL is the main pathogenic gene.OBJECTIVE:To investigate the effect of NIPBL gene on the proliferation and osteogenic differentiation of bene marrow mesenchymal stem cells.METHODS:The NIPBL+/-mice were constructed by NIPBL-Loxp and Cre mice and used as experimental group,and the wild-type NIPBL+/+mice served as control group.Mouse bone marrow mesenchymal stem cells were isolated and cultured in the two groups.Cell proliferation was detected using cell counting kit-8 assay when the cells were passed to the third generation.Osteoblastic differentiation was then compared between two groups after osteogenesis induction.RESULTS AND CONCLUSION:The proliferation capacity of bone marrow mesenchymal stem cells in the experimental group was lower than that in the control group(P<0.05).The activity of alkaline phosphatase in the experimental group was significantly lower than that in the control group on the 7th day of osteogenic induction(P<0.05).The expression levels of osteogenic genes and proteins(Runx2 and OCN)in the experimental group were lower than those in the control group after osteogenic induction(P<0.05).On the 21st day of osteogenic induction,results from alizarin red staining indicated there were more red calcium nodules in the control group than the experimental group under inverted microscope.These findings suggest that NIPBL gene knockout can reduce the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells.