Objective:

2

To investigate potential mechanisms of anti-atherosclerosis by berberine (BBR) using ApoE

-/-

mice.

Methods:

2

Eight 8-week-old C57BL/6J mice were used as a blank control group (normal)

and 56 8-week-old AopE

-/-

mice were fed a high-fat diet for 12 weeks

according to a completely random method

and were divided into the model group

BBR low-dose group (50 mg/kg

BBRL)

BBR medium-dose group (100 mg/kg

BBRM)

BBR high-dose group (150 mg/kg

BBRH)

BBR+nuclear factor erythroid 2-related factor 2 (NRF2) inhibitor group (100 mg/kg BBR+30 mg/kg ML385

BBRM+ML385)

NRF2 inhibitor group (30 mg/kg

ML385)

and positive control group (2.5 mg/kg

atorvastatin)

8 in each group. After 4 weeks of intragastric administration

samples were collected and serum

aorta

heart and liver tissues were isolated. Biochemical kits were used to detect serum lipid content and the expression levels of malondialdehyde (MDA) and superoxide dismutase

(SOD) in all experimental groups. The pathological changes of atherosclerosis (AS) were observed by aorta gross Oil Red O

aortic sinus hematoxylin-eosin (HE) and Masson staining. Liver lipopathy was observed in mice by HE staining. The morphology of mitochondria in aorta cells was observed under transmission electron microscope. Flow cytometry was used to detect reactive oxygen species (ROS) expression in aorta of mice in each group. The content of ferrous ion Fe

2+

in serum of mice was detected by biochemical kit. The mRNA and protein relative expression levels of NRF2

glutathione peroxidase 4 (GPX4) and recombinant solute carrier family 7 member 11 (SLC7A11) were detected by quantitative real time polymerase chain reaction (RT-qPCR) and Western blot

respectively.

Results:

2

BBRM and BBRH groups delayed the progression of AS and reduced the plaque area(

P

<

0.01). The characteristic morphological changes of ferroptosis were rarely observed in BBR-treated AS mice

and the content of Fe

2+

in BBR group was significantly lower than that in the model group (

P

<

0.01). BBR decreased ROS and MDA levels in mouse aorta

increased SOD activity (

P

<

0.01)

significantly up-regulated NRF2/SLC7A11/GPX4 protein and mRNA expression levels (

P

<

0.01)

and inhibited lipid peroxidation. Compared with the model group

the body weight

blood lipid level and aortic plaque area of ML385 group increased (

P

<

0.01); the morphology of mitochondria showed significant ferroptosis characteristics; the serum Fe

2+

MDA and ROS levels increased (

P

<

0.05 or

P

<

0.01)

and the activity of SOD decreased (

P

<

0.01). Compared with BBRM group

the iron inhibition effect of BBRM+ML385 group was significantly weakened

and the plaque area significantly increased (

P

<

0.01).

Conclusion:

2

Through NRF2/SLC7A11/GPX4 pathway

BBR can resist oxidative stress

inhibit ferroptosis

reduce plaque area

stabilize plaque

and exert anti-AS effects.