Objective

2

To investigate the mechanisms by which

Yiqi Tongluo Formula

inhibits vascular intimal hyperplasia based on the ang

iotensin II type 1 receptor-associated protein （ATRAP）/NADPH oxidase 4 （NOX4）/reactive oxygen species （ROS） signaling pathway.

Methods

2

Rats were randomly divided into a sham operation group， a blank group， a model group， a positive drug group， and low-， medium-， and high-dose

Yiqi Tongluo Formula

groups （

n

=15 each）. Except for the sham operation and blank groups， all other groups underwent balloon injury of the common carotid artery to establish a vascular intimal hyperplasia model， and the sham operation group received ligation of the external carotid artery only. No drug intervention was given to the sham operation， blank， or model groups. The positive drug group received atorvastatin calcium tablets （1.02 mg/kg）. The low-， medium-， and high-dose groups were administered

Yiqi Tongluo Formula

at doses of 6.0， 12.0， and 24.0 g/kg （crude drug）， respectively， once daily for 14 days. Hematoxylin-eosin staining was used to observe pathological changes in the common carotid artery. Luminal area （LA）， area within the internal elastic lamina （IELA）， and area within the external elastic lamina （EELA） were measured to calculate intimal area （IA）， medial area （MA）， IA/MA ratio， intimal thickness （IT）， medial thickness （MT）， intimal area hyperplasia rate （HRIA）， and intimal thickness hyperplasia rate （HRIT）. Oxidative stress-related indicators， including ROS， malondialdehyde （MDA）， lactate dehydrogenase （LDH）， and superoxide dismutase （SOD）， were measured by ELISA. Immunofluorescence staining was used to detect protein expression of ATRAP， NOX4， smooth muscle 22α （SM22α）， and osteopontin （OPN）. Western blot was performed to assess the expression of ATRAP， NOX4， SM22α， OPN， matrix metalloproteinase-9 （MMP-9）， and tissue inhibitor of metalloproteinases-1 （TIMP-1） in carotid artery tissues.

Results

2

Compared with the model group， all

Yiqi Tongluo Formula

groups showed reduced vascular intimal hyperpl

asia， with lower IA， IT， HRIA， HRIT， ROS， LDH， and MDA levels （

P

<

0.01）， and higher SOD levels （

P

<

0.01）. Protein expression of ATRAP， SM22α， and TIMP-1 was significantly increased （

P

<

0.01）， whereas expression of NOX4， OPN， and MMP-9 was significantly decreased （

P

<

0.01）.

Conclusion

2

Yiqi Tongluo Formula

may inhibit vascular intimal hyperplasia by regulating the ATRAP/NOX4/ROS signaling pathway， suppressing vascular smooth muscle cell （VSMC） proliferation and migration， alleviating oxidative stress， and maintaining the balance between TIMP-1 and MMP-9.