ObjectiveTo investigate the therapeutic effect of Siegesbeckiae Herba water decoction （SWD） at different doses on atherosclerosis （AS） in a mouse model induced by a high-fat diet and analyze its potential mechanism of action.MethodsThirty-six male ApoE^-/- mice were randomly divided into six groups： blank control group， model group， low-dose， medium-dose， and high-dose SWD groups， and positive control group. Firstly， the AS mouse model was created by feeding mice a high-fat diet. After successful modeling， the low-， medium-， and high-dose SWD groups were intragastrically administered with SWD at 0.65， 1.3， 2.6 g·kg^-1， respectively. The positive control group was intragastrically administered with 30 mg·kg^-1 of atorvastatin calcium aqueous solution， while the blank and model groups received an equal volume of 0.9% sodium chloride solution via oral gavage， all administered for 12 weeks. During the administration period， the general condition of the mice was observed and recorded daily. Before sampling， color Doppler ultrasound was performed to observe the pathological changes in atherosclerotic plaques in the aortic wall of mice. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in aortic tissue in mice， and oil red O staining was used to detect the atherosclerotic plaque area in the aorta. Enzyme-linked immunosorbent assay （ELISA） was used to detect the serum lipid indices and the levels of interleukins （IL-1β， IL-4， IL-6， and IL-10） and tumor necrosis factor-α （TNF-α） in mice. Protein expression levels of IKKα， IKKβ， and NF-κB p65 in mouse aortic tissue were detected by Western blot.ResultsCompared with the blank control group， the model group showed a significant increase in body weight. The results of color Doppler ultrasound showed enhanced vascular wall echo， suggesting the presence of atherosclerotic plaques. HE staining showed foam cell aggregation， fibrous connective tissue proliferation， and vascular intima injury in the aortic tissue. Oil red O staining showed a significant increase in the plaque area in the aortic tissue （P<0.01）. ELISA results indicated significantly elevated levels of IL-1β， IL-6， TNF-α， total cholesterol （TC）， triglyceride （TG）， and low-density lipoprotein （LDL） in mouse serum （P<0.01）， as well as significantly decreased levels of IL-4， IL-10， and high-density lipoprotein （HDL） （P<0.01）. Western blot results showed that the expression of IKKα， IKKβ， and NF-κB p65 in mouse aortic tissue increased significantly （P<0.01）. Compared with those in the model group， mice in the middle- and high-dose SWD groups showed significant weight loss. In the high-dose group， the aortic vascular wall echoes were weakened， and the atherosclerotic plaques were reduced. The aortic lesions of mice in the medium- and high-dose SWD groups were significantly alleviated. The plaque area percentage showed an inverse correlation with the administered dose in all groups treated with SWD （P<0.05）. In the medium-dose SWD group， serum levels of IL-1β， IL-6， TNF-α， TC， TG， and LDL were significantly decreased （P<0.05， P<0.01）， while those of IL-4 and IL-10 were significantly increased （P<0.01）. In the high-dose SWD group， levels of IL-1β， IL-6， TNF-α， TC， TG， and LDL were significantly decreased （P<0.01）， while IL-4， IL-10， and HDL were significantly increased （P<0.01）. The IKKα and IKKβ expression was significantly decreased in the low-dose SWD group （P<0.05）， and IKKα， IKKβ， and NF-κB p65 were significantly decreased in the medium- and high-dose SWD groups （P<0.05， P<0.01）.ConclusionSWD may exert therapeutic effects on AS by regulating the expression of related inflammatory factors through the NF-κB signaling pathway， thereby reducing inflammation， plaque area， and lipid content in the body.

Siegesbeckiae Herba;atherosclerosis;nuclear factor-κB （NF-κB）;inflammation