Inhibitory Effect of β-Sitosterol on the Ang II-Induced Proliferation of A7r5 Aortic Smooth Muscle Cells

作者：Chen, Yuankun; He, Shumiao; Zeng, Ao; He, Siqing; Jin, Xiaobao; Li, Chunmei; Mei, Wenjie; Lu, Qun^*

来源：Analytical Cellular Pathology-Cellular Oncology, 2023, 2023: 2677020.

DOI：10.1155/2023/2677020

• CYCLIN D1
• APOPTOSIS
• ATHEROSCLEROSIS
• OVEREXPRESSION
• PHYTOSTEROLS
• PROGRESSION
• AUTOPHAGY
• MIGRATION
• PROTECTS
• BCL-2

Context. Excessive proliferation of vascular smooth muscle cells (VSMCs) plays a critical role in the development of cardiovascular diseases. beta-Sitosterol exerts protective effects against the cardiovascular disease. However, whether beta-sitosterol protects against the excessive proliferation of VSMCs remain unclear. Objective. To explore the effects of beta-sitosterol on VSMC proliferation. Materials and Methods. A7r5 cells were pretreated with 2 mu M angiotensin II (Ang II) for 24 hr to establish an excessive VSMC proliferation model, followed by treatment with beta-sitosterol for 24 hr. Cells were divided into five groups: control, Ang II, and Ang II + beta-sitosterol (2, 4, 8 mu M). CCK-8 assay, flow cytometry, and Ad-mCherry-GFP-LC3B assay analyzed cell proliferation, cell cycle, cell apoptosis, and autophagic flux. Additionally, the expression of proteins was detected by the western blotting. Results. beta-Sitosterol effectively inhibited Ang II-induced A7r5 cell proliferation (IC50 : 6.841 mu M at 24 hr). It achieved this by arresting cell cycle progression, promoting apoptosis, inhibiting autophagy, and suppressing the contractile-synthetic phenotypic switch. Mechanistically, beta-sitosterol downregulated PCNA, Cyclin D1, and Bcl-2, while upregulating pro-caspase 3, cleaved-caspase 3, and Bax to induce cell cycle arrest and apoptosis. Additionally, it suppressed the contractile-synthetic phenotypic transformation by downregulating OPN and upregulating alpha-SMA. The Ad-mCherry-GFP-LC3B Assay and western blotting revealed beta-sitosterol's autophagy inhibitory effects by downregulating LC3, ULK1, and Beclin-1 while upregulating P62 expression. Discussion and Conclusion. This study found for the first time that beta-sitosterol could inhibit the proliferation of A7r5 cells induced by Ang II. beta-Sitosterol treatment may be recommended as a therapeutic strategy to prevent the cardiovascular diseases.

• 单位
  广东药学院; 海南医学院