Summary
There is a significant body of evidence which suggests that the α-isoform of the CCAAT/enhancer binding protein (C/EBPα) plays a central regulatory role in energy metabolism in the liver. However, there is little information available regarding regulation of its expression in this tissue. In this study, we examined the effect of hormones and diabetes on its expression in rat H4IIE hepatoma cells and in rat liver. Treatment of H4IIE cells with dexamethasone led to a threefold increase in C/EBPα mRNA within 4 h. Insulin treatment produced a bi-phasic response, initially reducing mRNA levels up to the 4 h time point, but after 8 h a twofold increase in C/EBPα mRNA was observed. Treatment with 8-chlorophenylthio-cAMP produced a twofold induction of C/EBPα mRNA after 8 h. Western analysis indicated that the changes in mRNA in response to hormonal treatment generally resulted in corresponding alterations in C/EBPα protein levels. Finally, we observed an inhibition of C/EBPα gene expression in streptozotocin-diabetic rat liver, reflected by a decrease in both mRNA and protein levels that were partially reversed by insulin treatment. These results indicate that the expression of C/EBPα in liver is under complex control by both hormonal and metabolic signals, which is consistent with its role as a trans -regulator of genes which play a role in energy metabolism. [Diabetologia (1997) 40: 1117–1124]
Article PDF
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 21 January 1997 and in revised form: 28 April 1997
Rights and permissions
About this article
Cite this article
Crosson, S., Davies, G. & Roesler, W. Hepatic expression of CCAAT/enhancer binding protein α: hormonal and metabolic regulation in rats. Diabetologia 40, 1117–1124 (1997). https://doi.org/10.1007/s001250050796
Issue Date:
DOI: https://doi.org/10.1007/s001250050796