PTGS2 and Hyperglycemia: Moreover, hyperglycemia seems to be linked to the upregulation of COX-2 with an increase in the vasoconstrictive activity of thromboxane (TXB2) and prostaglandins (PGE2) concentrations, reduction of prostacyclin, increased superoxide production, and subsequent lipid peroxidation and protein nitrosylation [35,36,37,38].