ABSTRACT
D-4F, an apolipoprotein A-I (apoA-I) mimetic peptide, possesses distinctly anti-atherogenic effects. However, the biological functions and mechanisms of D-4F on the hyperplasia of vascular smooth muscle cells (VSMCs) remain unclear. This study aimed to determine its roles in the proliferation and migration of VSMCs. In vitro, D-4F inhibited VSMC proliferation and migration induced by ox-LDL in a dose-dependent manner. D-4F up-regulated heme oxygenase-1 (HO-1) expression in VSMCs, and the PI3K/Akt/AMP-activated protein kinase (AMPK) pathway was involved in these processes. HO-1 down-regulation with siRNA or inhibition with zinc protoporphyrin (Znpp) impaired the protective effects of D-4F on the oxidative stress and the proliferation and migration of VSMCs. Moreover, down-regulation of ATP-binding cassette transporter A1 (ABCA1) abolished the activation of Akt and AMPK, the up-regulation of HO-1 and the anti-oxidative effects of D-4F. In vivo, D-4F restrained neointimal formation and oxidative stress of carotid arteries in balloon-injured Sprague Dawley rats. And inhibition of HO-1 with Znpp decreased the inhibitory effects of D-4F on neointimal formation and ROS production in arteries. In conclusion, D-4F inhibited VSMC proliferation and migration in vitro and neointimal formation in vivo through HO-1 up-regulation, which provided a novel prophylactic and therapeutic strategy for anti-restenosis of arteries.
Subject(s)
Apolipoprotein A-I/pharmacology , Atherosclerosis/prevention & control , Heme Oxygenase-1/genetics , Muscle, Smooth, Vascular/drug effects , Neointima/prevention & control , Protective Agents/pharmacology , AMP-Activated Protein Kinases/genetics , AMP-Activated Protein Kinases/metabolism , ATP Binding Cassette Transporter 1/genetics , ATP Binding Cassette Transporter 1/metabolism , Animals , Aorta, Thoracic/cytology , Aorta, Thoracic/drug effects , Aorta, Thoracic/metabolism , Atherosclerosis/genetics , Atherosclerosis/metabolism , Atherosclerosis/pathology , Cell Movement/drug effects , Cell Proliferation/drug effects , Gene Expression Regulation , Heme Oxygenase-1/metabolism , Lipoproteins, LDL/antagonists & inhibitors , Lipoproteins, LDL/pharmacology , Male , Muscle, Smooth, Vascular/cytology , Muscle, Smooth, Vascular/metabolism , Myocytes, Smooth Muscle/cytology , Myocytes, Smooth Muscle/drug effects , Myocytes, Smooth Muscle/metabolism , Neointima/genetics , Neointima/metabolism , Neointima/pathology , Phosphatidylinositol 3-Kinases/genetics , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Rats , Rats, Sprague-Dawley , Signal TransductionABSTRACT
Apolipoprotein A-I (apoA-I) mimetic peptide exerts many anti-atherogenic properties. However, the underlying mechanisms related to the endothelial protective effects remain elusive. In this study, the apoA-I mimetic peptide, D-4F, was used. Proliferation assay, wound healing, and transwell migration experiments showed that D-4F improved the impaired endothelial proliferation and migration resulting from ox-LDL. Endothelial adhesion molecules expression and monocyte adhesion assay demonstrated that D-4F inhibited endothelial inflammation. Caspase-3 activation and TUNEL stain indicated that D-4F reduced endothelial cell apoptosis. A pivotal anti-oxidant enzyme, heme oxygenase-1 (HO-1) was upregulated by D-4F. The Akt/AMPK/eNOS pathways were involved in the expression of HO-1 induced by D-4F. Moreover, the anti-oxidation, pro-proliferation, and pro-migration capacities of D-4F were diminished by the inhibitors of both eNOS (L-NAME) and HO-1 (Znpp). Additionally, downregulation of ATP-binding cassette transporter A1 (ABCA1) by siRNA abolished the activation of Akt, AMPK and eNOS, and reduced the upregulation of HO-1 triggered by D-4F. Furthermore, D-4F promoted the reendothelialization of injured intima in carotid artery injury model of C57BL/6J mice in vivo. In summary, these findings suggested that D-4F might be a powerful candidate in the protection of endothelial cells and the prevention of cardiovascular disease (CVD).
