| First Author | Kim MJ | Year | 2020 |
| Journal | Mol Cells | Volume | 43 |
| Issue | 3 | Pages | 264-275 |
| PubMed ID | 32150794 | Mgi Jnum | J:297736 |
| Mgi Id | MGI:6479203 | Doi | 10.14348/molcells.2020.2197 |
| Citation | Kim MJ, et al. (2020) Reduced EGFR Level in eIF2alpha PhosphorylationDeficient Hepatocytes Is Responsible for Susceptibility to Oxidative Stress. Mol Cells 43(3):264-275 |
| abstractText | Reactive oxygen species (ROS) play a significant role in intracellular signaling and regulation, particularly when they are maintained at physiologic levels. However, excess ROS can cause cell damage and induce cell death. We recently reported that eIF2alpha phosphorylation protects hepatocytes from oxidative stress and liver fibrosis induced by fructose metabolism. Here, we found that hepatocyte-specific eIF2alpha phosphorylation-deficient mice have significantly reduced expression of the epidermal growth factor receptor (EGFR) and altered EGFR-mediated signaling pathways. EGFR-mediated signaling pathways are important for cell proliferation, differentiation, and survival in many tissues and cell types. Therefore, we studied whether the reduced amount of EGFR is responsible for the eIF2alpha phosphorylationdeficient hepatocytes' vulnerability to oxidative stress. ROS such as hydrogen peroxide and superoxides induce both EGFR tyrosine phosphorylation and eIF2alpha phosphorylation. eIF2alpha phosphorylation-deficient primary hepatocytes, or EGFR knockdown cells, have decreased ROS scavenging ability compared to normal cells. Therefore, these cells are particularly susceptible to oxidative stress. However, overexpression of EGFR in these eIF2alpha phosphorylationdeficient primary hepatocytes increased ROS scavenging ability and alleviated ROS-mediated cell death. Therefore, we hypothesize that the reduced EGFR level in eIF2alpha phosphorylation-deficient hepatocytes is one of critical factors responsible for their susceptibility to oxidative stress. |
