DDIT3 and endothelial dysfunction: Endothelial dysfunction was observed in PA-treated HAECs, including impaired total antioxidant capacity, cell viability, NO levels, and eNOS, MFN2 and UQCRC1 protein levels, as well as significant up-regulation of IL6, MMP1, and CHOP mRNA levels (Figure 2b–g, Figure 3c and Figure 4c,f).