Sung-Young Shin1,*, Taeyong Kim2,*, Ho-Sung Lee1,3, Jun Hyuk Kang1,3, Ji Young Lee2, Kwang-Hyun Cho1,3
& Do Han Kim2
1Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Korea. 2 School of Life Sciences and Systems Biology Research Center, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712, Korea. 3Graduate School of Medical Science and Engineering, KAIST, Daejeon 305-701, Korea.
* These authors contributed equally to this work.
Correspondence to: Kwang-Hyun Cho or Do Han Kim.
Abstract
How cell fate (survival or death) is determined and whether such determination depends on the strength of stimulation has remained unclear. In this study, we discover that the cell fate of cardiomyocytes switches from survival to death with the increase of β-adrenergic receptor (β-AR) stimulation. Mathematical simulations combined with biochemical experimentation of β-AR signalling pathways show that the gradual increment of isoproterenol (a non-selective β1/β2-AR agonist) induces the switching response of Bcl-2 expression from the initial increase followed by a decrease below its basal level. The ERK1/2 and ICER-mediated feed-forward loop is the hidden design principle underlying such cell fate switching characteristics. Moreover, we find that β1-blocker treatment increases the survival effect of β-AR stimuli through the regulation of Bcl-2 expression leading to the resistance to cell death, providing new insight into the mechanism of therapeutic effects. Our systems analysis further suggests a novel potential therapeutic strategy for heart disease.