淫羊藿苷通过FXR降低LPS/TLR4诱导的肝星状细胞自噬和活化

Icariin Ameliorates LPS / TLR4 Induced Hepatic Stellate Cell Activatio and Autophagy via FXR

目的探讨淫羊藿苷(ICA)对脂多糖/TLR4途径诱导的肝星状细胞的活化和自噬的作用,并进一步研究是否与FXR蛋白相关。方法通过脂多糖刺激肝星状细胞-T6细胞株并通过TLR4 siRNA和淫羊藿苷干预。吖啶橙(AO)染色和MDC染色观察自噬体改变;激光共聚焦观察Beclin-1和LC3B的表达;流式细胞仪检测细胞线粒体膜电位;Western检测NF-κB(p65)、LC3B-Ⅱ、胶原蛋白Ⅰ、TGF-β1和α-SMA蛋白变化。另对淫羊藿苷干预组用Z-Guggulsterone(Z-Gug)进行干预,Western检测LC3B、Beclin-1和FXR的改变。结果脂多糖刺激肝星状细胞-T6自噬体数量增加、上调Beclin-1和LC3B表达、降低细胞线粒体膜电位和增加NF-κB(p65)、LC3B-Ⅱ、胶原蛋白Ⅰ、TGF-β1和α-SMA表达。该作用可被TLR4 siRNA和淫羊藿苷剂量依赖性阻断;淫羊藿苷可以增加FXR表达且被Z-Gug阻断。结论淫羊藿苷通过减少自噬降低脂多糖/TLR4途径诱导的肝星状细胞的活化和FXR有关。

OBJECTIVE To investigate the effects of icariin （ICA） on autophagy and activation of HSC-T6 cell line induced by lipopolysaceharide （LPS） ,and further research whether this effect is associated with FXR protein. METHODS The HSC-T6 hepatic stellate cell was stimulated with LPS and then treated with ICA of three different doses and TLR4 siRNA. Autophagy changes were ob- served through the acridine orange （AO） and MDC staining, expression of Beclin- 1 and LC3B were determined via laser scanning con- focal microscopy, cell mitochondrial membrane potentials were detected using flow cytometry and the proteins of NF-κB （ p65 ） , LC3B- Ⅱ , CollagenI,TGF-β1, α-SMA were measured through Western blot. Furthermore, the ICA treatment group was intervened with Z-Gug- gulsterone（Z-Gug）. The expressions of LC3B,Beclin-1 and FXR were measured through Western blot. RESULTS Compared with the normal group, LPS significantly increased autophagy, up-regulated expression of Beclin-1 and LC3B, decreased mitochondrial mem- brane protentials and increased expression of NF-κB（ p65 ） , LC3B-Ⅱ , Collagen Ⅰ,TGF-β1 and α-SMA. However, the effects of LPS on HSC-T6 could be partly inhibited by TLR4 siRNA and ICA in a dose-dependent manner. Moreover, ICA increased expression of FXR and could be blocked by Z-Gug treatment. CONCLUSION ICA ameliorated LPS/TLR4 can induce hepatic stellate cell activation by reduction autophagy and association with FXR protein.