Blood pressure control is not enough to normalize endothelial repair by progenitor cells

Transplantation of endothelial progenitor cells improves myocardial hypertrophy in spontaneously hypertensive rats through HO-1/CREB3/AKT axis

Hypertensive myocardial hypertrophy produces a hostile microenvironment characterized by cardiomyocyte hypertrophy, inflammation and oxidative stress, which also leads to endothelial progenitor cells (EPCs) dysfunction, preventing EPC migration, adhesion and angiogenesis. Heme oxygenase-1 (HO-1) is an intracellular protein that plays an important role in angiogenesis and cell survival. The upregulation of cAMP response element-binding protein 3 (CREB3) is closely related to the formation of endothelial cells. The purpose of this study was to evaluate the role of HO-1 and CREB3 in EPCs and their effects on hypertensive myocardial hypertrophy. EPCs were transfected with HO-1 adenoviral overexpression vector (Ad-HO-1) or together with CREB3 siRNA (si-CREB3), or transfected with CREB3 adenoviral overexpression vector (Ad-CREB3) or together with HO-1 siRNA, and then treated with 100 nM Ang Ⅱ for 12 h. Overexpressing HO-1 or CREB3 promoted adhesion to extracellular matrix, cell migration, and angiogenesis, inhibited the secretion of inflammatory factors TNF-α and IL-6, and reduced ROS level, ICAM-1 and MCP-1 mRNA expression levels in EPCs treated with Ang Ⅱ. Online prediction and Co-IP assay showed that HO-1 interacts with CREB3, and they promote expression of each other. EPC-conditioned medium supplemented with CREB3 recombinant protein decreased the levels of ANP and BNP mRNA in H9C2 cells treated with Ang Ⅱ and alleviated oxidative stress. Ad-CREB3 transfected EPCs promoted the phosphorylation of AKT in vivo and in vitro, thereby improving myocardial swelling and dysfunction in SHR rats. Taken together, transplantation of CREB3 overexpressing EPCs alleviates myocardial hypertrophy in spontaneously hypertensive rats by promoting HO-1 protein expression and AKT phosphorylation.

Effect of Peptidylarginine Deiminase 4 on Endothelial Progenitor Cell Function in Peripheral Arterial Disease

At present, the global prevalence of peripheral arterial disease is increasing year by year, and it has become a worldwide disease. Studies have shown that transplanting endothelial progenitor cells (EPCs) into ischemic tissues can improve the tissue ischemia, thereby having a therapeutic effect on peripheral arterial diseases. This indicates that EPCs play a therapeutic effect in peripheral arterial disease. Recent studies have shown that peptidylarginine deiminase (PAD) is involved in the regulation of epigenetics and its inhibitor Cl-amidine can improve endothelium-dependent vasodilation and significantly reduce the formation of arterial thrombosis. It can also play a role in hematopoietic stem cells that share the same origin with EPCs. Therefore, we speculate that PAD4 may also have an effect on EPCs through a similar mechanism, thereby participating in the damage and repair of peripheral arterial disease. Therefore, we first detected the expression of PAD4 in EPCs of peripheral arterial disease and detected changes in the number and function of endothelial progenitor cells in peripheral blood after injecting the PAD4 inhibitor Cl-amidine into mice. A mouse model of lower limb ischemia was established to explore the effect of PAD4 on the function of EPCs in peripheral arterial disease. The results show that PAD4 is highly expressed in peripheral arterial diseases and the PAD4 inhibitor Cl-amidine can increase the number of EPCs and can treat peripheral arterial diseases by improving the proliferation, migration, and vascularization of EPCs.