牛磺熊去氧胆酸抑制四氯化碳诱导的大鼠肝纤维化

Tauroursodeoxycholic acid inhibits carbon tetrachloride-induced liver fibrosis in rats

目的:探讨牛磺熊去氧胆酸(TUDCA)对四氯化碳(CCl4)诱发大鼠肝纤维化的抑制作用.方法:健康6周龄♂SD大鼠75只,随机分为空白对照组、模型对照组、TUDCA低剂量组、TUDCA高剂量组、己酮可可碱(PTX)阳性对照组,每组15只.用40%的CCl4油溶液,大鼠背部皮下注射3mL/kg(首次5mL/kg)造大鼠肝纤维化模型.各组给予相应浓度干预药物溶液灌胃8wk,检测血清纤维化指标HA、LN、Ⅳ-C;胶原纤维染色(Masson三色染色)观察各组胶原纤维面积比变化;免疫组织化学SP法观察TGF-β1及α-SMA在大鼠肝组织中的表达及分布变化.结果:8wk后,TUDCA及PTX干预组与模型组相比,血清HA、LN、Ⅳ-C有明显降低(146.33±35.13,162.2±24.80,137.14±22.24vs252.83±51.94;77.20±11.84,66.80±16.78,82.00±10.74vs108.00±30.00;14.14±2.59,12.60±3.17,10.09±2.22vs25.08±5.93,均P<0.05);肝组织纤维间隔变细或消失,形成弥漫性肝硬化结节减少,胶原面积比降低(P<0.05);免疫组织化学结果显示,TUDCA及PTX干预组与模型组相比,TGF-β1及α-SMA阳性表达减少,图像软件半定量分析结果显示差异有显著性(P<0.05).而TUDCA低剂量组与高剂量组及PTX组三者之间结果差异无显著性.结论:TUDCA对CCl4诱发的大鼠肝纤维化有拮抗作用,主要是通过减少TGF-β1合成,抑制HSC细胞活化,降低细胞外基质合成,延缓肝纤维化进程.

AIM：To determine the inhibitory effects of tauroursodeoxycholic acid （TUDCA） on carbon tetrachloride-induced liver fibrosis in rats.METHODS：A total of 75 healthy Sprague-Dawley rats were randomly divided into five groups：normal control group,model group,low-dose TUDCA group,high-dose TUDCA group and pentoxifylline （PTX） group.Hepatic fibrosis was induced in rats by hypodermic injection of carbon tetrachloride （40%）.The low-and high-dose TUDCA groups were orally administered TUDCA at doses of 50 and 100 mg/（kg·d）,respectively.The PTX group was orally administered PTX at a dose of 16 mg/（kg·d）.The treatment lasted 8 wk for all the groups.Hematoxylin and eosin staining and Masson＇s trichrome staining of liver tissue was performed for histopathological evaluation of liver fibrosis.Serum parameters of liver fibrosis were detected by enzyme-linked immunosorbent assay.The expression of transforming growth factor-β1 （TGF-β1） and α-smooth muscle actin （α-SMA） in liver tissue was detected by immunohistochemistry.RESULTS：Compared with the model group,the levels of serum hyaluronic acid （HA）,laminin （LN） and type IV collagen （IV-C） significantly decreased in the low-and high-dose TUDCA groups and the PTX group （HA：146.33 ± 35.13,162.2 ± 24.80 and 137.14 ± 22.24 vs 252.83 ± 51.94;LN：77.20 ± 11.84,66.80 ± 16.78 and 82.00 ± 10.74 vs 108.00 ± 30.00;IV-C：14.14 ± 2.59,12.60 ± 3.17 and 10.09 ± 2.22 vs 25.08 ± 5.93,all P 〈0.05）.Compared with the model group and normal control group,fibrous septa became thinner and even disappeared,and the number of diffuse cirrhotic nodules and the area of collagen fiber decreased in the TUDCA and PTX intervention groups （all P 〈0.05）.The expression intensity of TGF-β1 and α-SMA proteins was significantly lower in the TUDCA and PTX intervention groups than in the model group （all P 〈0.05）,but showed no significant difference between the TUDCA and PTX treatment groups.CONCLUSION：TUDCA can prevent carbon tetrachloride-induced liver fibrosis in rats by reducing TGF-β1 synthesis,inhibiting hepatic stellate cell activation and decreasing extracellular matrix synthesis.