Effects of Ruanmailing in Blocking Early Stages of Atherosclerosis by TNF-α Regulation via Kir2.1

OBJECTIVE: Ruanmailing oral solution consists of 16 herbs, has anti-lipid peroxidation activity, protects vascular endothelial cells, and improves vascular elasticity. It is an effective drug for the treatment of atherosclerosis (AS). The objective of this study was to investigate the mechanism underlying the antiatherosclerotic effects of Ruanmailing oral solution. METHODS: Macrophages were isolated, cultured, and divided into the macrophage control; macrophage foam cell; and low-, medium-, and high-concentration Ruanmailing groups. Cell proliferation was analyzed by cell counting kit-8 (CCK-8) assay, and the expression levels of inward-rectifier potassium ion channel 2.1 (Kir2.1) and tumor necrosis factor (TNF)-α were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analyses. RESULTS: CCK-8 assay results showed that the tested concentrations of Ruanmailing solution did not affect macrophage proliferation. RT-PCR and Western blot assays indicated that TNF-α expression increased significantly with the formation of macrophage foam cells (P < 0.05). In addition, significant decreases in Kir2.1 and TNF-α expression were observed following treatment with various concentrations of Ruanmailing (P < 0.05). CONCLUSION: Based on the results, Ruanmailing affects macrophage foam cell formation by regulating Kir2.1 expression, which in turn reduces TNF-α expression and exerts antiatherosclerotic effects. These findings provide a scientific basis for the use of traditional Chinese medicine for AS treatment.