OBJECTIVETo observe the effects of Guanxinkang (GXK) decoction, a compound traditional Chinese herbal medicine, on serum lipids and apolipoprotein A I (ApoA I), apolipoprotein B (ApoB), apolipoprotein E (ApoE), C-reactive protein (CRP), serum amyloid A protein (SAA) and fibrinogen (Fbg) concentrations of ApoE-knockout mice with atherosclerosis, and to explore the mechanism of GXK decoction in anti-atherosclerosis.METHODSSeventy 6-week-old ApoE-knockout mice receiving a high-cholesterol diet were used to induce atherosclerosis and were randomly divided into 5 groups: untreated group, simvastatin group and low- (drug concentration is 0.864 g/mL), medium- (1.728 g/mL), and high-dose (3.456 g/mL) GXK groups. Another fourteen 6-week-old C57BL/6J mice were used as the normal control. Two 12-week-old mice were randomly selected from the normal control and the ApoE-knockout mice respectively to observe vulnerable plaque in the mouse's aortic by hematoxylin-eosin staining. Blood was collected from venous plexus of eye socket after gavage of corresponding drugs once daily for 8 weeks continuously, and then the serum was separated. Triglyceride (TAG) and total cholesterol (TC) were measured by enzyme-coupled assay; low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) were measured by selective precipitation method. Serum levels of ApoA I and ApoB were determined by turbidimetry. Double-antibody sandwich enzyme-linked immunosorbent assay was used to detect ApoE, CRP, SAA and Fbg concentrations in serum.RESULTSCompared with the normal control group, the levels of serum TC, TAG, LDL-C, ApoB, CRP, SAA and Fbg in the untreated group were increased (P<0.05), and the serum concentrations of HDL-C, ApoA I and ApoE in the untreated group were decreased (P<0.05). After treatment, GXK decoction and simvastatin improved the dyslipidemia by increasing the concentrations of ApoA I and HDL-C and decreasing the concentrations of TC, TAG, LDL-C, ApoB, CRP, SAA and Fbg (P<0.05). The high-dose GXK decoction had the most marked effects on SAA and Fbg and the serum lipids compared with the low-dose and medium-dose GXK and simvastatin.CONCLUSIONGXK decoction may not only provide an active effect on hyperlipidemia, but also down-regulate the levels of serum CRP, SAA and Fbg. GXK decoction exerts an anti-atherosclerosis effect in ApoE-knockout mice.