含有RGD序列环肽介导的干扰素脂质体对大鼠肝纤维化的治疗作用

目的探讨通过构建针对大鼠肝星状细胞(HSC)受体介导的靶向脂质体(RGD—SSL),观察包裹重组人干扰素α1b(IFN—α1b)的长循环脂质体(SSL)对胆管结扎大鼠肝纤维化的治疗效果。方法实验大鼠随机分成4组：假手术组、肝硬化模型组(BDL组)、IFN—SSL治疗(BDL IFN—SSL)组、1FN-配基-SSL治疗(BDL 1FN—RGD—SSL)组,每组10只。构建包裹IFN—d1b的SSL,通过聚乙二醇(PEG)将能与HSC特异性结合的配基cyclo(RGD)]连接于脂质体的表面,观察对胆管结扎大鼠肝纤维化的治疗作用。检测各组大鼠血清肝功能、血清肝纤维化指标、肝组织羟脯氨酸含量、肝脏组织学的变化,运用RT-PCR法检测肝脏Ⅰ型胶原的表达。分离HSC,用Western印迹检测α-平滑肌肌动蛋白(α—SMA)的表达。结果IFN-RGD—SSL治疗组大鼠肝纤维化程度均明显低于IFN—SSL治疗组,肝功能指标、血清肝纤维化指标、肝羟脯氨酸含量和肝脏组织学改变较IFN—SSL治疗组明显改善;肝脏Ⅰ型胶原mRNA和HSC的α—SMA表达量明显下降。结论构建的受体介导的长循环脂质体对大鼠胆管结扎肝纤维化具有靶向性的治疗作用。

Antifibrotic effects of cyclic RGD-peptide mediated liposomal interferon: an experimental on rats

OBJECTIVE: To evaluate the antifibrotic effect of receptor-mediated sterical stability liposome (SSL) targeting hepatic stellate cells (HSCs) and containing recombinant human interferon-alpha 1b (IFNalpha-1b) on hepatic cirrhosis. METHODS: The ligand, cyclo (RGD) with specific affinity to HSCs, was incorporated via PEG into the lipid bilayers of SSL. Forty male SD rats were randomly divided into 4 equal groups: liver fibrosis model group undergoing double ligation and cutting of the common bile duct (BDL group), BDL + IFN-SSL group, undergoing BDL and injection of IFN 50,000 IU per week via caudal vein for 4 times; IFN-RGD-SSL treatment group, undergoing BDL and injection of IFN-RGD-SSL (equal to 50,000 IU per week) via caudal vein for 4 times; and sham operation group used as control. The rats were killed 24 hours after the last injection. Their livers and serum samples were collected. Pathological changes of the liver were observed with HE and alpha-SMA immunohistochemical staining. Biochemical automatic analyzer was used to test the serum indices of liver function: ALT, AST, total bilirubin (TBIL), alkaline phosphatase, and gamma-glutamine (gamma-GT). Radioimmunoassay method was used to examine the s serum index of liver fibrosis: HA, procollagen III (PCIII), LN, and CIV. Colorimetry was used to examine the level of hydroxyl proline (Hyp). RT-PCR was used to detect the mRNA expression of type I collagen. Western blotting was used to examine the protein expression of alpha-SMA of HSC. RESULTS: Compared with the control group, liver fibrosis was seen in the other 3 groups, especially in the BDL group. In comparison with the sham operation group, the levels of serum indices of liver fibrosis, liver hydroxyl proline content, and expression of type I collagen mRNA and alpha-SMA protein in liver were significantly higher in the other groups (all P < 0.05), being significantly lower in the BDL + IFN-RGD-SSL group than in the BDL + IFN-SSL group (all P < 0.05). CONCLUSION: The receptor-mediated IFN-RGD-SSL displays good targeting antifibrotic effects on liver fibrosis.