Insulin and igfs enhance hepatocyte differentiation from human embryonic stem cells via the PI3K/AKT pathway

Authors

  • Nataly L. Magner,

    1. Stem Cell Program and University of California Davis Medical Center, Sacramento, California, USA
    Search for more papers by this author
    • Author contributions: N.M.: collection and/or assembly of data, data analysis and interpretation, and manuscript writing; Y.J.: collection and/or assembly of data; J.W: data analysis and interpretation and manuscript writing; J.A.N.: conception and design, data analysis and interpretation, and manuscript writing; M.A.Z.: conception and design, data analysis and interpretation, financial support, and manuscript writing; P.Z.: conception and design, data analysis and interpretation, financial support, manuscript writing, and final approval of manuscript.

  • Yunjoon Jung,

    1. Stem Cell Program and University of California Davis Medical Center, Sacramento, California, USA
    Search for more papers by this author
  • Jian Wu,

    1. Transplant Research Program Department of Internal Medicine, University of California Davis Medical Center, Sacramento, California, USA
    Search for more papers by this author
  • Jan A. Nolta,

    1. Stem Cell Program and University of California Davis Medical Center, Sacramento, California, USA
    Search for more papers by this author
  • Mark A. Zern,

    1. Transplant Research Program Department of Internal Medicine, University of California Davis Medical Center, Sacramento, California, USA
    Search for more papers by this author
  • Ping Zhou

    Corresponding author
    1. Stem Cell Program and University of California Davis Medical Center, Sacramento, California, USA
    • Correspondence: Ping Zhou, Ph.D., Stem Cell Program, Department of Internal Medicine, University of California Davis, 2921 Stockton Blvd, Sacramento, California 95817, USA. Telephone: 916-703-9371; Fax: 916-703-9310; e-mail: ping.zhou@ucdmc.ucdavis.edu

    Search for more papers by this author

Abstract

Human embryonic stem cells (hESCs) can be progressively differentiated into definitive endoderm (DE), hepatic progenitors, and hepatocytes, and thus provide an excellent model system for the mechanistic study of hepatocyte differentiation, which is currently poorly understood. Here, we found that insulin enhanced hepatocyte differentiation from hESC-derived DE. Insulin activated the PI3K/AKT pathway, but not the mitogen-activated protein kinase pathway in the DE cells, and inhibition of the PI3K/AKT pathways by inhibitors markedly inhibited hepatocyte differentiation. In addition, insulin-like growth factor 1 (IGF1) and IGF2 also activated the PI3K/AKT pathway in DE cells and their expression was robustly upregulated during hepatocyte differentiation from DE. Furthermore, inhibition of IGF receptor 1 (IGF1R) by a small molecule inhibitor PPP or knockdown of the IGF1R by shRNA attenuated hepatocyte differentiation. Moreover, simultaneous knockdown of the IGF1R and the insulin receptor with shRNAs markedly reduced the activation of AKT and substantially impaired hepatocyte differentiation. The PI3K pathway specifically enhanced the expression of HNF1 and HNF4 to regulate hepatocyte differentiation from DE. Although inhibition of the PI3K pathway was previously shown to be required for the induction of DE from hESCs, our study revealed a positive role of the PI3K pathway in hepatocyte differentiation after the DE stage, and has advanced our understanding of hepatocyte cell fate determination. Stem Cells 2013;31:2095–2103

Ancillary