PECAM1 and diabetes mellitus: Immunostaining for 8-hydroxy-deoxyguanosine (8-HDG), a well-established marker of oxidative DNA damage, was significantly elevated in paraffin-embedded LV sections of DM_CKD, both in the myocardium and CD31-labeled coronary microvessels, while there was no change in DM (Fig. 8 a–c).