Objective        To determine the effect of lentivirus-mediated mouse meprin α on the formation of atherosclerotic plaques.       Methods        Eighteen ApoE

-/-

mice (age 18 mo

nths) were divided randomly into 3 groups

control

LvMep1A

and LvGFP groups. All the mice were fed with high-fat dieting for 14 weeks

and then tail injection with placebo

LvMep1A

or LvGFP respectively at the beginning of the 11th week. Value of weight

blood pressure

and plasma lipid levels were measured by automatic biochemical analyzer. Meprin α protein levels were measured by Western blotting and ELISA respectively. The size of plaque area were determined by HE staining and quantified with Image plus pro software. Apoptotic cell were determined by TUNEL. The inflammatory factors were measured by ELISA.       Results        Compared with control group

the protein expression of meprin α was significantly increased by 3.7-folds and 3.4-folds in the plasma and vascular tissue respectively (

P

<

0.05). Compared with control group

the body weight and plasma levels of triglycerides

and LDL were significantly increased in LvMep1A mice (

P

<

0.05). On the contrary

the value of HDL level was significantly decreased in LvMep1A mice (

P

<

0.05). Compared with control group

the size of plaque area was significantly increased (

P

<

0.05)

and the percentage of TUNEL positive cells were significantly increased by 58.25% in LvMep1A mice (

P

<

0.05). Additionally

the plasma levels of IL-1β

TNF-α and MMP-9 were significantly increased in LvMep1A mice when compared with control mice (

P

<

0.05). However

the levels of MCP-1 and IL-6 had no significant change in LvMep1A mice (

P

>0.05). Compared with control mice

the values in LvGFP mice have no significant change (

P

>0.05).       Conclusion        Meprin α significantly induces the formation and progression of atherosclerosis plaque

which might be due to its improving the release of inflammatory factors and inducing cell apoptosis in atherosclerosis plaque.