Anti-atherosclerotic function of Astragali Radix extract: downregulation of adhesion molecules in vitro and in vivo
1 Department of Cardiology, Cardiovascular Research Institute, Shenyang Northern Hospital, Shenyang, China
2 The Affiliated Hospital of Liaoning University of TCM, Shenyang, China
3 Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China
4 Department of Cardiology, Shenyang General Hospital, 83 Wenhua Road, Shenyang 110840, China
BMC Complementary and Alternative Medicine 2012, 12:54 doi:10.1186/1472-6882-12-54Published: 26 April 2012
Atherosclerosis is considered to be a chronic inflammatory disease. Astragali Radix extract (ARE) is one of the major active ingredients extracted from the root of Astragalus membranaceus Bge. Although ARE has an anti-inflammatory function, its anti-atherosclerotic effects and mechanisms have not yet been elucidated.
Murine endothelial SVEC4-10 cells were pretreated with different doses of ARE at different times prior to induction with tumor necrosis factor (TNF)-α. Cell adhesion assays were performed using THP-1 cells and assessed by enzyme-linked immunosorbent assay, western blotting and immunofluorescence analyses to detect the expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), phosphorylated inhibitor of κB (p-iκB) and nuclear factor (NF)-κB. We also examined the effect of ARE on atherosclerosis in the aortic endothelium of apolipoprotein E-deficient (apoE−/−) mice.
TNF-α strongly increased the expression of VCAM-1 and ICAM-1 accompanied by increased expression of p-iκB and NF-κB proteins. However, the expression levels of VCAM-1 and ICAM-1 were reduced by ARE in dose- and time-dependent manners, with the strongest effect at a dose of 120 μg/ml incubated for 4 h. This was accompanied by significantly decreased expression of p-iκB and inhibited activation of NF-κB. Immunofluorescence analysis also revealed that oral administration of ARE resulted in downregulation of adhesion molecules and decreased expression of macrophages in the aortic endothelium of apoE−/− mice. ARE could suppress the inflammatory reaction and inhibit the progression of atherosclerotic lesions in apoE−/− mice.
This study demonstrated that ARE might be an effective anti-inflammatory agent for the treatment of atherosclerosis, possibly acting via the decreased expression of adhesion molecules.