title: [Effects of astragali radix extract on matrix metalloproteinase 9 expression and atherosclerotic plaque formation in aorta of apolipoprotein E deficient mice fed with high fat diet].
abstract: OBJECTIVE
  To explore the effects of astragali radix extract on the expressions of matrix metalloproteinase 9 (MMP-9) and the formation of atherosclerotic plaque in aortic atherosclerotic plaques of apolipoprotein E-deficient mice (ApoE-/-).
  
  
  METHODS
  Male 8-week-old ApoE-/- mice fed with high fat diet were randomly divided into four groups (n=12 each): control group (saline 0.2 ml/d), atorvastatin group (atorvastatin 10 mg×kg(-1)×d(-1)), low-dose astragali radix extract group (1.25 g×kg(-1)×d(-1)) and high-dose astragali radix extract group (5 g×kg(-1)×d(-1)). After 12 weeks, serum oxLDL was measured by the method of ELISA. The formation of atherosclerotic plaque was determined in HE and oil red O stained aortic slice. The expressions of macrophage and MMP-9 in the aortic plaque were detected by immune fluorescence and immunohistochemistry staining method.
  
  
  RESULTS
  Similarly as atorvastatin, astragali radix extract significantly decreased the level of serum oxLDL in ApoE-/-1 mice in a dose-dependent manner. The level of oxLDL in the high-dose astragali radix extract group [(5.2±6.1) µg/ml] was significantly lower than that in the control group [(15.8±5.4) µg/ml, P<0.01]. The area of atherosclerosis plaques was smaller (17.24%±4.22% vs. 49.87%±9.37%, P<0.01) and the penetration degree of plaques in the arterial wall was relieved in the high-dose astragali radix extract group compared to those in the control group (P<0.01). The expressions of Mac3 in atherosclerosis plaques of the high-dose astragali radix extract group was also significantly lower than in the control group (P<0.01). The mean absorbance value of the expression of MMP-9 in the high-dose astragali radix extract group (0.0154±0.0014)was significantly lower than that in the control group (0.0263±0.0065) (P<0.01).
  
  
  CONCLUSIONS
  Similar as atorvastatin, astragali radix extract can dose-dependently inhibit the expression of MMP-9 and the formation of the atherosclerotic plaque in ApoE-/- mouse, probably by reducing the serum oxLDL, inhibiting macrophage infiltration, migration and secretion of MMP-9.
authors.affiliation: Intervention Center, Affiliated Hospital of Liaoning University of Tranditional Chinese Medicine, Shenyang 110032, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: You
authors.forename: Yan
authors.initials: Y
authors.lastname: Duan
authors.forename: Xiao-lin
authors.initials: XL
authors.lastname: Zhang
authors.forename: Jian
authors.initials: J
authors.lastname: Kang
authors.forename: Cheng-hui
authors.initials: CH
authors.lastname: Yan
authors.forename: Xiu-li
authors.initials: XL
authors.lastname: Zhang
authors.forename: Jia-tao
authors.initials: JT
authors.lastname: Feng
authors.forename: Ya-ling
authors.initials: YL
authors.lastname: Han
mesh_terms: D000818:Animals; D001011:Aorta / Q000503:physiopathology; D001057:Apolipoproteins E / Q000235:genetics; D027883:Astragalus Plant; D027885:Astragalus propinquus; D059305:Diet, High-Fat; D004365:Drugs, Chinese Herbal / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D058226:Plaque, Atherosclerotic / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology*
chemical_list: D001057:Apolipoproteins E; D004365:Drugs, Chinese Herbal; C027492:Huang Qi; D020780:Matrix Metalloproteinase 9; C501830:Mmp9 protein, mouse