MAPK3 and myocardial infarction: Experimental studies have shown that normal high-density lipoprotein (HDL) can promote angiogenesis in human umbilical vein endothelial cells by stimulating the phosphorylation of ERK1/2, and HDL inhibits ERK1/2 phosphorylation to block angiogenesis in patients with acute myocardial infarction (Zhang et al., 2018) (Figure 3).