Effect and Mechanism of Buyang Huanwu Tang on Atherosclerotic Plaque Based on Treg Cells / 中国实验方剂学杂志

ABSTRACT

Objective:To explore the effect and mechanisms of Buyang Huanwu Tang (BYHWT) on atherosclerotic plaque based on regulatory T cells (Treg) and inflammation. Method:Totally 50 ApoE knockout(ApoE-/-)mice aged 8 weeks were randomly divided into model group, low, medium, high-dose BYHWT groups, positive control group, and C57/BL mice were taken as control group. The model group and the BYHWT group were given high-fat diet for 12 weeks, while the control group was given normal diet. After successful modeling, BYHWT groups were given drugs (5, 10, 20 g·kg-1) through intragastric administration, the positive control group was given rapamycin (4 mg·kg-1), while the control group and the model group were given equal doses normal saline through intragastric administration for 4 weeks. Four weeks later, the mice were sacrificed. Manufactured paraffin sections were prepared for the aortic sinus of the heart. The plaque area was evaluated by hematoxylin and eosin (HE) staining, and the number of Treg cells in immunohistochemical staining plaque was detected. Blood was collected from eye canthus of mice, the expression of inflammatory factors in peripheral blood was detected by enzyme-linked immunosorbent assay (ELISA), and the forkhead box P3 (Foxp3) gene expression in peripheral blood was detected by Real-time fluorescent quantitative polymerase chain reaction (PCR). Result:Compared with the control group, the area of atherosclerotic plaques in the model group was significantly increased (P<0.01), the contents of serum tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were significantly increased (P<0.05), and transforming growth factor-β (TGF-β) and interleukin-10 (IL-10) were significantly decreased (P<0.05), and the peripheral blood Fxop3 mRNA expression was decreased (P<0.05). Compared with the model group, the plaque areas in middle-dose and high-dose BYHWT groups were significantly reduced(P<0.05), the peripheral blood TNF-α and IL-6 contents were decreased (P<0.01), the TGF-β and IL-10 expressions were increased in the high-dose group (P<0.05, P<0.01), the number of Treg cells in the plaque was increased in the high-dose group (P<0.01), and the peripheral blood Fxop3 mRNA expression was increased in each BYHWT group (P<0.01). Conclusion:BYHWT has an anti-atherosclerosis effect, which may be related to the increase of the number of Treg cells and thereby inhibiting the inflammatory response in vivo.