Objective:

2

To investigate the effect of quercetin on ATP binding cassette transporter A1 (ABCA1)

liver X receptor (LXR)

and proprotein convertase subtilisin/kexin type 9 (PCSK9) expressions in apoE-knockout (ApoE

-/-

) mice.

Methods:

2

The high-fat diet-induced atherosclerosis (AS) in ApoE

-/-

mice was established. Thirtysix mice were divided into 3 groups using random number table method: model group (

n

=12)

quercetin group (

n

=12)

and atorvastatin group (

n

=12)

with C57BL/6J mice of the same strain and age as the control group (

n

=12). Quercetin group and atorvastatin group were administrated with quercetin and atorvastatin by oral gavage

with doses of 12.5 and 4 mg/(kg•d)

respectively. Animals in the control and model groups were given an equal volume of distilled water by oral gavage once per day for a total of 12 weeks. Western blot and immunohistochemical methods were employed to determine the aortic ABCA1

LXR-α and PCSK9 protein expression. Enzyme linked immunosorbent assay method was used to detect the expression of serum total cholesterol (TC)

triglyceride (TG)

high density lipoprotein-cholesterol (HDL-C)

low density lipoproteincholesterol (LDL-C)

tumor necrosis factor-α (TNF-α)

interleukin-6 (IL-6)

and IL-10

combined with tissue pathological examination.

Results:

2

ApoE

-/-

mice fed with a high-fat diet had notable atherosclerosis lesions

with reduced ABCA1

LXR-α and IL-10 levels (all

P

<

0.01)

elevated PCSK9

TNF-α and IL-6 expression

and increased TC and LDL-C contents (all

P

<

0.01). After quercetin intervention

the areas of AS plaques and the expressions of PCSK9

TNF-α and IL-6 were significantly reduced (all

P

<

0.01)

while the expressions of ABCA1 and LXR-α were increased significantly (all

P

<

0.01).

Conclusion:

2

Quercetin effectively interfered with AS development by regulating the expressions of ABCA1

LXR-α and PCSK9 in ApoE

-/-

mice.