Overexpression Of SHP-1 Mediated By Lentivirus Restrains Atherosclerosis Progression In Mice Models

Background and ObjectivesAtherosclerosis is the most common, most important and most basic disease among vascular diseases and its feature is that the artery wall gets thickening and hardening and then lose its elasticity, and finally the lumen finally shrinks; the formation of atherosclerotic lesions is the result of inflammation- fiber proliferative reaction that is made by artery to intimal lesion, including local lipid and complex carbohydrate aggregation, proliferation of fibrous tissue, calcium based deposits and inflammatory reaction, etc., these reactions form plaque, induce plaque hemorrhage,plaque rupture and the formation of local thrombosis, resulting in a series of vicious incidents; some serious patients may even lost their lives. Atherosclerosis is a long-term chronic pathological process that is featured by lipid metabolic disorders,vascular endothelial cell damage, inflammatory cell infiltration, plaque rupture and formation of thrombosis. Therefore, the development of atherosclerosis gene therapy can start from these four aspects to find the target of treatment. CD40 is a type I transmembrane protein. Studies have shown that there is a high expression of CD40 in human and animal models with atherosclerosis plaques. Inhibition of CD40 signal transduction may promote atherosclerotic plaque regression; SHP- 1 is the important regulatory protein and its over-expression can block the activation and inflammatory response of CD40 to the downstream p38 MAPK protein; SHP-1( SH2-domaincontaining protein-tyrosine phosphatase-1,SHP-1) containing SH2 domain structure is a kind of intracellular protein tyrosine phosphatase and its N-terminal contains 2Src homology structure domains, which are mainly expressed in hematopoietic cells,such as T cells, B cells, monocytes, and epithelial cell lines. Through the establishment of atherosclerosis model mice, this study made use of lentiviral vector in vivo to transfect atherosclerotic plaques and study the effect of SHP-1 lentiviral vector that contains SH2 domain structure in atherosclerosis mice model, so as to provide targeted prevention and treatment for atherosclerotic plaque.MethodsForty-five ApoE knock-out mice, 8 week old, were randomly assigned to three groups: Control group, GFP transfection group and SHP-1 transfection group. All mice were placed with carotid collars on the right common carotid arteries near its bifurcation, following fed with high-fat diet for 8 weeks and then transfected with GFP blank vector or SHP-1 lentivirus(SHP-1-LV). The fluorescence density of plaques, body weight, the levels of plasma total cholesterol(TC) and triglyceride(TG)were determined at 1st, 2nd, and 6th week after lentivirus transfection. Furthermore, the mRNA and protein expressions of SHP-1, interleukin-6(IL-6), tumor necrosis factor-?(TNF-?), matrix metalloproteinase(MMP-2), and MMP-9 were analyzed by qRT-PCR and Western blot. Additionally, pathological analysis of the plaques was also performed by section staining.ResultsThe density of fluorescence was observed in the plaques at 1st, 2nd, and 6th week after lentivirus transfection, with a highest density at 2nd week. The body weight and the levels of TC and TG in mice were not influenced by lentivirus transfection.Moreover, SHP-1-LV transfection significantly upregulated the expressions of SHP-1mRNA and protein, but inhibited IL-6, TNF-?, MMP-2, MMP-9 expressions. In addition, SHP-1-LV transfection also decreased plaque size ratio and lipid content in right common carotid arteries.ConclusionsSHP-1 overexpression accelerates the regression of atherosclerotic plaque, thus emerging SHP-1 as a target for atherosclerosis prevention and treatment.