Objective: To explore the effect of modified Buyang Huanwutang on the expression of Toll like receptor 4 (TLR4)

myeloid differentiation factor 88 (MyD88) and tumor necrosis factor receptor-associated factor-6(TRAF-6)

nuclear factor kappa B (NF-κB) in the apolipoprotein E gene knockout mice (ApoE-/- mice)

in order to discuss the mechanism of modified Buyang Huanwutang for the prevention and treatment of atherosclerosis (AS). Method: Thirty male ApoE-/- mice were randomly divided into three groups:model group

modified Buyang Huanwutang group and atorvastatin group

and 10 C57BL/6J mice were the control group.Model group

modified Buyang Huanwutang group and atorvastatin group were given high-fat diet.At the same time

modified Buyang Huanwutang group and simvastatin group were intragastrically administrated with modified Buyang Huanwutang (18.69 g · kg-1)

leech powder (0.39 g · kg-1) and atorvastatin (1.3 mg · kg-1).After 9 weeks of treatment

cholesterol (TC)

triglyceride (TG)

high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were detected.In addition

aorta segment was taken from the experiment animals to observe morphological changes by HE

and measure the ratio of the plaque area to the intravascular space.Real-time PCR and Western blot were used to determine the expressions of aortic TLR4

MyD88

TRAF-6

NF-κB. Result: In terms of blood lipid levels

compared with the normal group

TC

TG and LDL-C in the model group were significantly higher

while HDL-C levels was significantly lower (P<0.01).Compared with the model group

TC

TG and LDL-C in the modified Buyang Huanwutang group and the atorvastatin group were significantly lower

while HDL-C were significantly higher (P<0.01).HE staining showed no aortic plaque formation in C57BL/6J mice control group

and significant aortic plaque formation and increased inflammatory cell in model group.Compared with the model group

aortic vascular cells were arranged more orderly

inflammatory cell infiltration was reduced

and the proportion of aortic plaque in blood vessels reduced to varying degrees in Buyang Huanwutang group and atorvastatin group.To compared with C57BL/6J mice in the control group

mRNA and protein expressions of aortic TLR4

MyD88

TRAF-6 and NF-κB obviously increased in model group (P<0.01).mRNA and protein expressions of aortic TLR4

MyD88

TRAF-6 and NF-κB significantly decreased in both modified Buyang Huanwutang group and atorvastatin group

compared with model group (P<0.05

P<0.01). Conclusion: Both modified Buyang Huanwutang and atorvastatin have an effect in preventing the development of atherosclerosis.The mechanism could be related to intervention of TLR4 and its main components of downstream signal transduction pathway.