Stem Cell and Regenerative Medicine Lab, Beijing Institute of Transfusion Medicine, Beijing, 100850, China.
South China Institute of Biomedicine, Guangzhou, 510005, China.
Stem Cell Res Ther. 2017 Nov 7;8(1):252. doi: 10.1186/s13287-017-0703-2.
Bi-potential hepatic progenitor cells can give rise to both hepatocytes and cholangiocytes, which is the last phase and critical juncture in terms of sequentially hepatic lineage restriction from any kind of stem cells. If their differentiation can be controlled, it might access to functional hepatocytes to develop pharmaceutical and biotechnology industries as well as cell therapies for end-stage liver diseases.
In this study, we investigated the influence of Cx32 and Cx43 on hepatocyte differentiation of WB-F344 cells by in vitro gain and loss of function analyses. An inhibitor of Cx32 was also used to make further clarification. To reveal p38 MAPK pathway is closely related to Cxs, rats with 70% partial hepatectomy were injected intraperitoneally with a p38 inhibitor, SB203580. Besides, the effects of p38 MAPK pathway on differentiation of hepatoblasts isolated from fetal rat livers were evaluated by addition of SB203580 in culture medium.
In vitro gain and loss of function analyses showed overexpression of Connexin 32 and knockdown of Connexin 43 promoted hepatocytes differentiation from hepatic progenitor cells. In addition, in vitro and ex vivo research revealed inhibition of p38 mitogen-activated protein kinase pathway can improve hepatocytes differentiation correlating with upregulation of Connexin 32 expression and downregulation of Connexin 43 expression.
Here we demonstrate that Connexins play crucial roles in facilitating differentiation of hepatic progenitors. Our work further implicates that regulators of Connexins and their related pathways might provide new insights to improve lineage restriction of stem cells to mature hepatocytes.
双潜能肝祖细胞既能分化为肝细胞又能分化为胆管细胞，这是从任何干细胞向肝系逐步限制的最后阶段和关键节点。如果能够控制其分化，就有可能获得功能性肝细胞，从而为制药和生物技术行业以及终末期肝病的细胞治疗发展提供支持。
本研究通过体外获得和功能丧失分析，研究了 Cx32 和 Cx43 对 WB-F344 细胞向肝细胞分化的影响。还使用了 Cx32 的抑制剂进行进一步阐明。为了揭示 p38 MAPK 途径与 Cxs 密切相关，对 70%部分肝切除的大鼠进行腹腔内注射 p38 抑制剂 SB203580。此外，通过在培养中添加 SB203580 来评估 p38 MAPK 途径对从胎鼠肝脏分离的肝母细胞分化的影响。
体外获得和功能丧失分析表明，Connexin 32 的过表达和 Connexin 43 的敲低促进了肝祖细胞向肝细胞的分化。此外，体外和体内研究表明，p38 丝裂原活化蛋白激酶途径的抑制可以改善肝细胞分化，这与 Connexin 32 表达的上调和 Connexin 43 表达的下调相关。
本研究证明 Connexins 在促进肝祖细胞分化中发挥着重要作用。我们的工作进一步表明，Connexins 的调节剂及其相关途径可能为改善干细胞向成熟肝细胞的谱系限制提供新的思路。
