NOTCH4 and diabetes mellitus: Moreover, upregulated Notch ligands Dll4 and Jagged1 were observed in the skin of mice with diabetes (Figure 2(c)); however, the expression level of Notch4 and its target genes and ligands were significantly decreased in the ZZO treatment group, which demonstrated that ZZO can inhibit the activation of Notch4 signaling induced by DUs.