Send to

Choose Destination
See comment in PubMed Commons below

Regulated production of mature insulin in rat hepatoma cells: insulin production is up-regulated by dexamethasone and down-regulated by insulin.

Author information

  • 1Department of General Surgery, Zhongshan Hospital, Fudan University, Shanghai 200032, China.


We engineered an artificial beta cell line that produces an up-regulation of insulin in response to dexamethasone, and a down-regulation in response to insulin. A regulatory secretion system was devised by placing proinsulin cDNA containing genetically engineered furin endoprotease cleavage sites and a regulatory promoter for phosphoenolpyruvate carboxykinase (PEPCK), and an insulin expressing retrovirus vector (pN-PEPCK-mINS) was constructed and transfected into Hepa1-6 cells. The levels of insulin in culture medium and expression of insulin gene was estimated by radioimmunoassay and reverse transcription-polymerase chain reaction (RT-PCR), respectively. The clone (Hepa1-6/INS21), which secreted the highest level of insulin (10.79 microIU/106 cells per day), was selected for the regulation experiment. Compared with the non-treated Hepa1-6/INS21 cells, insulin production was augmented 3.6-fold by the addition of 10-7 M of dexamethasone. Addition of exogenous insulin to the culture medium decreased insulin mRNA expression remarkably on RT-PCR results, while dexamethasone increased insulin gene expression at the transcriptional level. The data indicated that genetically engineered Hepa1-6 cells could synthesize process and secrete insulin in a physiological manner.

[PubMed - indexed for MEDLINE]
Free full text
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for Shanghai Scientific and Technical Publishers
    Loading ...
    Write to the Help Desk