Gene transfer of endothelial NO synthase, but not eNOS, plus inducible NOS regressed atherosclerosis in rabbits

Abstract

The effects of in vivo gene transfer of endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) genes on severe atherosclerosis were investigated in rabbits. The recombinant adenoviruses, Ad.eNOS and Ad.iNOS, which respectively express eNOS and iNOS, were constructed. Atherosclerosis was induced by a balloon injury followed by a high cholesterol diet for 12 weeks. The rabbits were divided into six groups: Gp cont (no treatment); Gp null (adenovirus sham-infected); Gp eNOS (Ad.eNOS); Gp iNOS (Ad.iNOS); Gp e+i (Ad.eNOS plus Ad.iNOS); and Gp heNOS (a high dose of Ad.eNOS). Examinations were carried out 7 days after gene transfer. Plasma lipid levels were not significantly changed, but transfection with Ad.eNOS (Gp eNOS and Gp heNOS) decreased the tissue cholesterol concentration and regressed atherosclerotic lesions. Vessels treated with Ad.iNOS (Gp iNOS and Gp e+i) showed iNOS staining in the atheroma, and slight staining at other parts of the vessels; those treated with Ad.eNOS showed eNOS staining in the endothelium and subintima, and slight staining at other parts. Ad.eNOS transfection, but not Ad.iNOS or Ad.eNOS+Ad.iNOS transfection, improved the impaired aortic endothelium-dependent relaxation (EDR) and basal NO-dependent response, increased tissue cyclic GMP (cGMP), and decreased the release of O2- from vessels. eNOS treatment showed a decreasing tendency in regions with peroxynitrite staining, MMP1 staining, and suspected apoptosis. In conclusion, in vivo gene transfer of eNOS, but not iNOS or eNOS plus iNOS, regressed atherosclerosis. The relations among NO, O2-, and peroxynitrite may be critical, and lipid resorption from the lesions may be responsible for the regression.

High-Density Lipoproteins and Their Constituent, Sphingosine-1-Phosphate, Directly Protect the Heart Against Ischemia/Reperfusion Injury In Vivo via the S1P 3 Lysophospholipid Receptor

“…1,2,23,24 Release of NO and S1P receptor signaling are closely linked: Several groups, including ours, have shown that engagement of S1P receptors including S1P 3 by HDL and S1P leads to NO generation and vasodilation. 10,[25][26][27] In addition, S1P regulates the endothelial cell barrier by potently inhibiting transcellular and microvascular permeability and leakage, 28,29 effects that are also ascribed to NO. 19,20,30 In fact, NO may be mediating these S1P effects, as suggested by a recent study in which S1P inhibited TNF-␣-mediated monocyte adhesion to aortic endothelium in mice.…”

“…Because S1P receptors are present and functional in cardiomyocytes, 18 and both HDL and S1P are potent antiapoptotic signaling mediators in a number of experimental systems, 19,20 we tested whether they may protect cardiomyocytes against apoptosis. In vivo, HDL-treated mice and S1P-treated mice had Ϸ35% and Ϸ45% less apoptotic cell death, respectively, in the myocardial infarction area than vehicle-treated controls, as measured by terminal dUTP nick end-labeling staining ( Figure 3A).…”

Recent Advances in Understanding Endothelial Dysfunction in Atherosclerosis

“…Although various studies have shown that inhibition of eNOS either by pharmacological inhibitor or by eNOS gene knockout on the apolipoprotein E (ApoE -/-) background promotes atherogenesis, [49][50][51][52] and eNOS gene transfer showed improvement of endothelial function and inhibition or regression of atherosclerotic lesions in animal models, 53,54 controversial results are, however, reported in ApoE -/-mice which overexpress the eNOS gene (eNOS transgenic mice). In this mouse model, acceleration of atherosclerotic lesion formation was observed.…”

Possibility of the regression of atherosclerosis through the prevention of endothelial senescence by the regulation of nitric oxide and free radical scavengers

“…1). 24 There is the possibility of NO causING not only retardation but also regression of atherosclerosis.…”

“…79 Nitric oxide acts in multiple ways to prevent the progression of atherosclerosis, 80 and in our previous studies gene transfer of eNOS or ingestion of certain NO-boosting substances, such as L-arginine and L-citrulline, displayed additive effects on the retardation of the progression of atherosclerosis and the partial regression of advanced atherosclerosis in rabbits. 24,37 Then, what is the effect of NO on cellular senescence? Little is known about the beneficial effects of NO on endothelial senescence.…”