黄芩苷对脂多糖诱导的大鼠滑膜RSC-364细胞自噬的抑制作用

目的：探讨黄芩苷通过磷脂酰肌醇3-激酶/蛋白激酶B/雷帕霉素（PI3k/Akt/mTOR）信号通路对脂多糖（LPS）诱导的大鼠滑膜RSC-364细胞自噬的影响，并阐明其作用机制。方法：将对数生长期大鼠滑膜RSC-364细胞分为对照组、模型组、地塞米松（DXMS）组、10 μmol·L^-1黄芩苷组、20 μmol·L^-1黄芩苷组和40 μmol·L^-1黄芩苷组。对照组RSC-364细胞只加入培养基，其他各组RSC-364细胞均采用1 mg·L^-1LPS体外刺激12 h制作炎症细胞模型。采用MTT法检测各组RSC-364细胞存活率，RT-PCR法检测各组RSC-364细胞中PI3k、Akt、mTOR、Beclin1和微管相关蛋白-轻链3-Ⅱ（LC3-Ⅱ） mRNA表达水平，Western blotting法检测各组RSC-364细胞中Beclin1、Atg5、Atg7、Atg12、LC3-Ⅱ和P62蛋白表达水平。结果：与对照组比较，模型组RSC-364细胞存活率明显升高（P<0.01），模型组RSC-364细胞中PI3k、Akt、mTOR mRNA和P62蛋白表达水平明显降低（P<0.05或P<0.01），Atg5、Atg7、Atg12、LC3-Ⅱ、Beclin1 mRNA及蛋白表达水平明显升高（P<0.01）；与模型组比较，不同浓度黄芩苷组RSC-364细胞存活率明显降低（P<0.05或P<0.01），RSC-364细胞中PI3k、Akt、mTOR mRNA和P62蛋白表达水平明显升高（P<0.05或P<0.01），Atg5、Atg7、Atg12、LC3-Ⅱ、Beclin1 mRNA和蛋白表达水平降低（P<0.05或P<0.01）。结论：黄芩苷可能通过激活PI3k/Akt/mTOR信号通路抑制LPS诱导的RSC-364细胞自噬。

Inhibitory effect of baicalin on autophagy of synovial RSC-364 cells of rats induced by lipopolysaccharide

Objective: To investigate the effect of baicalin on the autophagy of the synovial RSC-364 cells of the rats induced by lipopolysaccharide (LPS)through PI3k/Akt/mTOR signal pathway, and to clarify its mechanism. Methods: The rat synovial RSC-364 cells in logarithmic growth phase were divided into control group, model group, dexamethasone(DXMS) group, 10μmol·L^-1baicalin group, 20μmol·L^-1 baicalin group and 40μmol·L^-1 baicalin group. The RSC-364 cells in control group were only supplemented with culture medium, and the RSC-364 cells in the other groups were stimulated with 1 mg·L^-1LPS for 12 h to make the inflammatory cell models. The survival rates of RSC-364 cells were detected by MTT assay, and the expression levels of PI3k, Akt, mTOR, Beclin1, and LC3-Ⅱ mRNA in the RSC-364 cells in various groups were detected by RT-PCR method;Western blotting method was used to detect the expression levels of Beclin1, Atg5, Atg7, Atg12, microtubule-associated protein-light chain 3-Ⅱ(LC3-Ⅱ), and P62 proteins in the RSC-364 cells in various groups. Results: Compared with control group, the survival rate of RSC-364 cells in model group was significantly increased (P<0.01), the expression levels of PI3k, Akt, mTOR mRNA and P62 protein in the RSC-364 cells in model group were significantly decreased (P<0.05 or P<0.01), and the expression levels of Atg5, Atg7, Atg12, LC3-Ⅱ, Beclin1 mRNA and proteins were significantly increased (P<0.01); compared with model group, the survival rates of RSC-364 cells in different concentrations of baicalin groups were significantly decreased (P<0.05 or P<0.01), the expression levels of PI3k, Akt, mTOR mRNA and P62 protein in the RSC-364 cells in different concentrations of baicalin groups were significantly increased (P<0.05 or P<0.01), and the expression levels of Atg5, Atg7, Atg12, LC3-Ⅱ and Beclin1 mRNA and proteins were decreased (P<0.05 or P<0.01). Conclusion: Baicalin may inhibit the LPS-induced autophagy of the RSC-364 cells by activating the PI3k/Akt/mTOR signaling pathway.