针刺对四氯化碳致肝纤维化大鼠肝脏中细胞外基质生成的抑制作用

目的:观察针刺治疗对四氯化碳致大鼠实验性肝纤维化的改善作用以及对纤维化肝脏中细胞外基质主要成分表达的影响。方法:将46只大鼠随机分为正常组(10只)、模型组(12只)、非穴组(12只)、穴位组(12只)。采用50%CCl4橄榄油溶液腹腔注射进行肝纤维化造模,同时针刺穴位组大鼠的"太冲"期门"肝俞"并电针"足三里"进行治疗。非穴组取穴为上述各穴左侧平移0.5cm处。造模和治疗6周后,颈总动脉取血用酶联免疫吸附法检测血清透明质酸(HA)、层黏连蛋白(LN)、Ⅲ型前胶原(PCⅢ)水平;然后处死大鼠,分离肝组织进行病理切片观察;并分离各组大鼠的肝星状细胞,以Western blot法检测α平滑肌肌动蛋白(α-SMA)、α1(Ⅰ)型胶原蛋白α1(I)collagen]、纤连蛋白(fibronectin)、基质金属蛋白酶-9(MMP-9)及金属蛋白酶组织抑制剂-1(TIMP-1)的蛋白表达,以Real-time PCR法检测α-SMA、α1(I)collagen和fi-bronectin的mRNA表达。结果:与正常组相比,模型组大鼠各项肝纤维化血清指标(HA、LN、PCⅢ含量)均明显升高(P<0.01,P<0.05);与模型组相比,穴位组血清HA、LN水平显著下降(P<0.05),非穴组无明显降低。针刺穴位可以降低肝星状细胞中α-SMA、α1(I)collagen和fibronectin的蛋白与基因表达(P<0.01,P<0.05),并上调MMP-9的蛋白表达(P<0.05),而对TIMP-1无明显影响(P>0.05)。结论:针刺穴位能有效改善四氯化碳导致的大鼠肝纤维化损伤,减少肝星状细胞分泌细胞外基质,从而抑制肝纤维化。

Inhibitory effect of acupuncture on hepatic extracellular matrix production in carbon tetrachloride-induced liver fibrosis rats

Objective To investigate the protective effect of acupuncture intervention on liver in carbon tetrachloride induced hepatic fibrosis rats and to reveal its impact on extracellular matrix production in the liver tissue.Methods A total of 46 SD rats were randomly divided into control group(n=10),model group(n=12),sham group(n=12) and acupuncture group(n=12).Hepatic fibrosis model was established by intraperitoneal injection of 50% olive oil containing CCl4(1 mL/kg),3 times in the 1st week and twice per week from the 2nd to the 6th week.During the fibrosis model establishment,acupuncture of "Taichong"(LR 3),"Qimen"(LR 14),"Ganshu"(BL 18) and "Zusanli"(ST 36) was carried out simultaneously.In the sham group,non-acupuncture points(0.5 cm left to the above-mentioned real points) were punctured.The treatment was conducted 3 times a week in the first three weeks and then twice a week for the last three weeks.Serum levels of hyaluronic acid(HA),liminin(LN)and precollagen(PCⅢ)were determined by enzyme linked immunosorbent assay for assessing the hepatic fibrosis degree.Primary hepatic stellate cells(HSC) were separated.Western blot assay was used to detect the expression of α-smooth muscle actin(SMA),α 1(I) collagen,fibronectin,matrix metalloproteinase(MMP)-9(components of extracellular matrix,ECM) and tissue inhibitor of metalloprotei-nase-1(TIMP-1,an inhibitor of MMP-9) proteins of HSC.Real-time quantitative polymerase chain reaction was used to detect the expression levels of α-SMA,α 1(I) collagen and fibronectin genes of HSC.Results Compared with the control group,contents of serum HA,LN and PCⅢ,expression levels of α-SMA,α 1(I) collagen and fibronectin proteins and genes,and TIMP-1 protein of HSC were significantly increased in the model group(P<0.01,P<0.05),while MMP-9 protein(an enzyme for degradating ECM) expression level of HSC in the model group was down-regulated significantly(P<0.01),suggesting a formation of hepatic fibrosis,impairment of the liver tissue fibrosis and imbalance of degradation of ECM.H.E.staining showed an ameliorated liver injury(disorder of hepatocyte arrangement,hepatocyte necrosis,formation of pseudolobule,etc.) in the acupuncture group in comparison with the model group.In comparison with the model group,serum HA and LN contents,expression levels of α-SMA,α 1(I) collagen and fibronectin proteins,and α-SMA mRNA and fibronectin mRNA of HSC were down-regulated considerably in the acupuncture group(P<0.05,P<0.01).On the contrary,MMP-9 protein expression level of HSC was up-regulated remarkably in the acupuncture group compared with the model group(P<0.05).No significant changes were found in all the aforementioned indexes in the sham group,and serum PCⅢ content as well as α 1(I) collagen mRNA and TIMP-1 protein expression levels of HSC in the acupuncture group compared with those in the model group(P>0.05).Conclusion Acu-puncture treatment can significantly relieve CCl4-induced hepatic fibrosis in hepatic fibrosis rats probably by inhibiting the synthe-sis and deposite of HA and LN,down-regulating expression levels of α-SMA,α 1(I) collagen and fibronectin proteins,and α-SMA mRNA and fibronectin mRNA of HSC as well as up-regulating MMP-9 protein expression of HSC.