Influence of oxidative stress on vascular calcification in the setting of coexisting chronic kidney disease and diabetes mellitus

Vascular calcification (VC) is a common complication in patients with chronic kidney disease (CKD). Particularly, CKD patients with diabetes mellitus (DM) develop severe VC. Specific mechanisms of VC remain unclear; this study aimed to investigate them in the context of coexisting CKD and DM, mainly regarding oxidative stress. Sprague Dawley rats were randomly divided into six groups as follows: control rats (Control), 5/6 nephrectomized rats (CKD), streptozotocin-injected rats (DM), 5/6 nephrectomized and streptozotocin-injected rats (CKD + DM), CKD + DM rats treated with insulin (CKD + DM + INS), and CKD + DM rats treated with antioxidant apocynin (CKD + DM + APO). At 18 weeks old, the rats were sacrificed for analysis. Compared to the control, DM and CKD groups, calcification of aortas significantly increased in the CKD + DM group. Oxidative stress and osteoblast differentiation-related markers considerably increased in the CKD + DM group compared with the other groups. Moreover, apocynin considerably reduced oxidative stress, osteoblast differentiation-related markers, and aortic calcification despite high blood glucose levels. Our data indicate that coexisting CKD and DM hasten VC primarily through an increase in oxidative stress; anti-oxidative therapy may prevent the VC progression.