[The Association Between Bone Morphogenic Protein-4 and Saphenous Vein Graft Pathology in Diabetic Patients Undergoing Coronary Revascularization].

Objectives: This study was designed to assess the expression levels of bone morphogenic protein-4 (BMP4) in saphenous veins harvested from diabetic patients undergoing coronary artery bypass grafting (CABG), and to investigate its association with morphological and pathological changes within the venous wall.

Methods: From January 2013 to December 2014, forty patients with type 2 diabetes mellitus (DM) and risk factors matched non-DM controls ( =40) were enrolled prospectively. Of the 40 DM patients, 24 had noninsulin-dependent diabetes (NIDM) and the remaining 16 had insulin-dependent diabetes (IDM). Segments of saphenous vein without surgical dilatation from these 80 patients were obtained. Vessel wall characteristics were evaluated by hematoxylin-eosin (HE) staining, and the expression and distribution of BMP4 was assessed by Western blot assay and immunohistochemistry analysis.

Results: The intimal and medial thickness of the saphenous veins harvested from DM patients were higher than those from non-DM controls. Compared with non-DM patients, the expression level of BMP4 was significantly elevated in diabetic veins ( <0.05), and BMP4 was highly expressed in smooth muscle cells located in the medial layer. Moreover, the expression levels of BMP4 in diabetic veins were significantly correlated with intimal thickness ( =0.655, <0.01), intimal area ( =0.684, <0.01), medial thickness ( =0.642, <0.01) and medial area ( =0.692, <0.01).

Conclusions: The pre-existing intimal and medial hyperplasia were significantly correlated with the high expression levels of BMP4 in saphenous veins harvested from diabetic patients, implying a potential role of BMP4 in the progression of vein graft stenotic diseases in this cohort of post-CABG patients. Future studies were warranted in investigating novel therapeutic strategy targeting at BMP4 for improving long-term vein graft patency.