Hypoxia changes the expression of the epidermal growth factor (EGF) system in human hearts and cultured cardiomyocytes

The epidermal growth factor (EGF) receptors HER2 and HER4 and the ligands HB-EGF and NRG1 are crucial for heart development. The

Hypoxia in the human heart alters the expression of the EGF system. Mimicking the HER2 down-regulation seen in the human heart in cultured cardiomyocytes inhibited their proliferation under hypoxic conditions. Interestingly, HB-EGF is induced in the hypoxic human hearts, and rescues hypoxic cardiomyocytes from the effect of HER2 inhibition in the in vitro model. The results have implications for future treatment strategies of patients with ischemic heart disease.