甘草次酸靶向肝星状细胞治疗肝纤维化的体内研究

目的观察以6-磷酸甘露糖修饰的白蛋白(M6P26-HSA)作为特异性载体,将甘草次酸(GA) 靶向释放到肝星状细胞治疗肝纤维化的效果。方法用125I记由M6P26-HSA和GA在体外合成新的偶合物GA-HSA-M6P26,观察其在体内的器官分布情况,用双重免疫组织化学的方法观察星状细胞对GA- HSA-M6P26的选择性摄取;选用Sirius红染色观察GA-HSA-M6P26对肝纤维化时胶原沉积的影响,用定量聚合酶链反应检测GA-HSA-M6P26对Ⅰ型前胶原mRNA表达的影响。结果静脉注射后10min,GA-HSA- M6P26选择性地分布于肝脏,摄取高峰可达(5 5.093±5.404)%。双重免疫组织化学染色证实GA-HSA- M6P26主要被星状细胞选择性摄取,GA-HSA-M6P26治疗后肝脏胶原沉积明显减少,Ⅰ型前胶原和α-平滑肌肌动蛋白mRNA表达明显降低。结论GA-HSA-M6P26可以选择性地分布于肝脏星状细胞,有显著的抗肝纤维化作用。

Targeting glycyrrhetinic acid to hepatic stellate cells in treating rat liver fibrosis

OBJECTIVES: We synthesized M6P26-HSA as a carrier for hepatic stellate cells (HSC) and coupled it with glycyrrhetinic acid (GA) to get a new conjugate GA-HSA-M6P26. Its organ distribution, specific combination with HSC and anti-fibrotic effect on livers were studied. METHODS: The GA-HSA-M6P26 was labeled with 125I and its organ distribution was detected radiologically. Selective combination of GA-HSA-M6P26 was observed with double immunocytochemic staining and collagen staining of the liver preparations was carried out using Sirius red staining method. The effect of the conjugate on mRNA expression of type I procollagen was studied with real-time PCR in vivo. RT-PCR was used for the effect on mRNA expression of alpha-SMA, MMP-9 and TIMP-1. RESULTS: 10 minutes after GA-HSA-M6P26 i.v. injection, 55%+/-5% of it was distributed in the livers. Double immunocytochemic staining showed that most of GA-HSA-M6P26 was taken up by HSC. With GA- HSA- M6P26 treatment, the collagen deposition in the liver decreased significantly compared with GA and M6P26-HSA treated rats. Similarly, the mRNA expression of type I procollagen and alpha-SMA dropped significantly. As to MMP-9 and TIMP-1, no significant change was shown. CONCLUSION: GA-HSA-M6P26 was selectively delivered to HSC and it showed a significant anti-fibrotic effect on rat liver fibrosis.