PTGS2 and diabetes mellitus: We found that expression of the pre-apoptotic BCL-2 family protein (BAX), the inflammatory-related protein cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) was higher in DM/hypoxic mice than controls; however, DM/hypoxic mice treated with shikonin had a dose-dependent reduction in the expression of these proteins, which returned to baseline (Fig. 5D).