BACKGROUND:Angiogenesis is the main treatment target of cardiovascular diseases.Bone morphogenetic protein 2 can modulate angiogenesis,but the regulatory effect of endothelial cell-specific bone morphogenetic protein 2 on angiogenesis is unclear. OBJECTIVE:To investigate the effect of endothelial-specific bone morphogenetic protein 2 on angiogenesis. METHODS:(1)Bioinformatics analysis:Cellular expression specificity and abundance of bone morphogenetic protein 2 were meta-analyzed by the PanglaoDB single-cell transcriptome database.The endothelial cell transcriptome sequencing dataset of the mouse hindlimb model and endocardial transcriptome dataset of mice overexpressing bone morphogenetic protein 2 were reanalyzed to evaluate the effect of endothelial cell bone morphogenetic protein 2 on the angiogenesis pathway.(2)Validation in vivo:After establishing the mouse hindlimb model,we compared the blood perfusion between the affected and sham limb at 7,14,and 21 days.The expression of the colocation of bone morphogenetic protein 2 and CD31 was explored by immunofluorescence and immunohistochemical staining.(3)Validation in vitro:The cultured human umbilical vein endothelial cells in vitro were divided into a control group,a hypoxia group,and a bone morphogenetic protein 2 inhibitor Noggin intervention group.After being cultured for 24 hours,the angiogenesis of endothelial cells in each group was observed. RESULTS AND CONCLUSION:(1)Endothelial cells are an important cell subgroup expressing bone morphogenetic protein 2.Both in the mouse hindlimb ischemia model and endocardial cells overexpressing bone morphogenetic protein 2,bone morphogenetic protein 2 was significantly up-regulated,and the angiogenesis pathway was significantly activated.(2)In the mouse hindlimb model,bone morphogenetic protein 2-positive blood vessels around neoangiogenesis increased significantly at 7 days of ischemia(P<0.05),and decreased significantly after 2 weeks of ischemia(P<0.001).(3)In umbilical vein endothelial cells cultured in vitro,after hypoxic intervention,the migration and sprouting of endothelial cells increased significantly,and the expression of angiogenesis factors vascular endothelial growth factor and platelet-derived growth factor was significantly increased.Noggin significantly reduced hypoxia-induced endothelial cell angiogenesis(P<0.001)and down-regulated the expression of vascular endothelial growth factor and platelet-derived growth factor(P<0.01).(4)These findings verify that endothelial cell-specific bone morphogenetic protein 2 can regulate angiogenesis,and targeting endothelial cell bone morphogenetic protein 2 is a promising way to improve angiogenesis.