Therapeutic effect of interleukin-10 on CCl4-induced hepatic fibrosis in rats

AIM: To study the therapeutic effect of exogenous interleukin-10 on CCl4-induced hepatic fibrosis in rats and its possible mechanisms. METHODS: Fourty-seven SD rats were randomly divided into control group (group N) and CCl4-induced hepatic fibrosis model group (group C). After CCl4 was given for 9 wk, the model group was divided into three groups. Rats in group M were put to death immediately,rats in group T were treated with IL-10 for another three wk and then put to death, rats in group R recovered after three weeks and were then killed. The degree of hepatic fibrosis was measured by HE staining and histological activity index (HAI). Histological activity index (HAI), change of collagen types I and III were measured by Picrosirius staining. The expression of TNF-alpha, MMP-2 and TIMP-1 in liver tissue was measured by S-P immunohistochemistry. RESULTS: CCl4- induced experimental rat hepatic fibrosis model was established successfully. The degree of hepatic fibrosis was markedly lower in group T than in groups M and R, and there was no difference between the two groups.The expression of collagen types I and III was significantly suppressed in group T and was slightly suppressed in groups M and R. The positive levels of TNF-alpha, MMP-2 and TIMP-1 in group M increased significantly compared to those in group N (P<0.01). The positive signals decreased significantly in groups T and R (P<0.01),but positive score was significantly lower in group T than in group R (P<0.01). CONCLUSION: Exogenous IL-10 can reverse CCl4-induced hepatic fibrosis in rats. IL-10 may exert its reversible effects on hepatic fibrosis by blocking CCl4-induced inflammation,inhibiting expression of MMP-2 and TIMP-1 and promoting resolution of collagen types I and III.     

Effect of TL-10 on the expression of HSC growth factors in hepatic fibrosis rat

AIM: To study the effect of IL-10 on the expression of growth factors - transforming growth factor-β1 (TGF-β1),epidermal growth factor (EGF), hepatocyte growth factor (HGF)and platelet-derived growth factor (PDGF)of hepatic stellate cells (HSCs) of hepatic fibrosis rat and the anti-fibrogenic role of exogenous IL-10.METHODS: Hepatic fibrosis was induced by CCl4administration intra-peritoneally. Sixty clean male SpragueDawley (SD) rats were randomly divided into three groups:normal control group (GN, 8 rats), hepatic fibrosis model group (GC, 28 rats) and IL-10 treated group (GI, 24 rats).At the beginning of the 7th and 11th wk, rats in each group were routinely perfused with pronase E and type Ⅳ collagenase through a portal vein catheter and the suspension obtained from the liver was spun by centrifugation with 11% Nycodenz density gradient to isolate HSCs. Histological examination was used to determine the degree of hepatic fibrosis. RT-PCR was employed to analyze mRNA expression from freshly isolated cells. Tmmunocytochemistry was performed to detect protein expression in primary cultured HSCs.RESULTS: Rat hepatic fibrosis was developed with the increase of injection frequency of CCl4, and HSCs were successfully isolated. At the 7th and 11th wk, TGF-β1, EGF,and HGF mRNA in GC increased obviously compared with GN (P = 0.001/0.042, 0.001/0.001, 0.001/0.001) and GI (P= 0.001/0.007, 0.002/0.001, 0.001/0.001). For TGF-β1,no difference was observed between GI and GN. For EGF,mRNA level in GI increased compared with GN during the 7th wk (P= 0.005) and 11th wk (P= 0.049). For HGF, mRNA level in GI decreased compared with GN at the 7th wk (P = 0.001) and 11th wk (P = 0.021). Between these two time points, TGF-β1 expression at the 7th wk was higher than that of the 11th wk (P = 0.049), but for EGF, the former was lower than the latter (P = 0.022). As for PDGF mRNA, there was no significant difference between these groups, but difference seemed to exist in protein levels.Results by immunocytochemistry of TGF-β1 and EGF were paralleled with the above findings.CONCLUSION: The expression of TGF-β1, EGF and HGF increased in HSC of hepatic fibrosis rat and decreased after treatment with IL-10. IL-10 plays an anti-fibrogenic role by suppressing growth factors expression.     

Antifibrotic effects of interleukin-10 on experimental hepatic fibrosis

BACKGROUND/AIMS: To study the effects of interleukin-10 on hepatic stellate cells and liver tissue in experimental rats hepatic fibrosis. METHODOLOGY: Rat hepatic fibrosis model induced by carbon tetrachloride was established. Liver tissues were harvested from the rats administered CCl4 with or without IL-10 treatment and the animals of the control group. The expression of TGF-beta1, MMP-2 and TIMP-1 in the liver tissues was measured by S-P immunohistochemistry. In addition, another model was established; HSCs in rats in each group were isolated. RT-PCR was employed to analyze TGF-beta1, MMP-2 and TIMP-1 mRNA expression in cells and immunocytochemistry was performed to detect protein expression of alpha-SMA, NF-kappaB, TGF-beta1, MMP-2 and TIMP-1 in HSCs. RESULTS: Rat hepatic fibrosis was developed successfully. The fibrosis changes were partially reversed by simultaneous administration of IL-10. The positive signals of TGF-beta1, MMP-2 and TIMP-1 were observed more frequently (P<0.05) in the CCl4-treated group compared to those in the IL-10-treated group and the control group. HSCs were successfully isolated. TGF-beta1, MMP-2 and TIMP-1 mRNA in HSCs increased obviously during the course of hepatic fibrosis, and their levels were decreased after the treatment with IL-10 (P<0.05). The immunocytochemistry positive levels for TGF-beta1, MMP-2, TIMP-1, alpha-SMA and NF-kappaB in the fibrogenesis group were increased significantly compared to the normal group (P<0.01). The positive signals decreased significantly (P<0.05) after the treatment with IL-10. CONCLUSIONS: The expression of TGF-beta1, MMP-2 and TIMP-1 increased in liver or in HSC of hepatic fibrosis rats and decreased after treatment with IL-10. The IL-10 could inhibit the activation of HSCs and make an antifibrogenic process come into effect in this way.     

Effect of Danshao Huaxian capsule on expression of matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1 in fibrotic liver of rats

AIM: To investigate the effects of Danshao Huaxian (DSHX) capsules, a preparation of traditional Chinese medicine, on the expression of matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of metalloproteinase-1 (TIMP-1) in the fibrous livers of rats. METHODS: Eighty male Wistar rats were randomly divided into normal control group (group A), CCl4-induced hepatic fibrosis group (group B), non-DSHX-treated group (group C), low dose-treated group (group D), and high dose-treated group (group E). Fibrous liver models in rats were induced by subcutaneous injection of CCl4, oral administration of alcohol and high-lipid/low-protein diet for 8 wk. After the models were established, the rats in groups D and E were orally given a low dose (0.5 g/kg) and a high dose (1.0 g/kg) of DSHX daily for 8 wk, respectively. Then, the liver indexes, serum hyaluronic acid (HA) and alanine aminotransferase (ALT) were examined. The degree of hepatic fibrosis was evaluated by optical microscopy. Hydroxyproline (Hyp) in the urine was determined, and the expression of MMP-1 and TIMP-1 was detected by immunohistochemical techniques. RESULTS: In groups D and E, the liver indexes, levels of serum HA and ALT reduced and development of hepatic fibrosis weakened significantly. The urinary Hyp and expression of MMP-1 in the liver tissues elevated, but the expression of TIMP-1 decreased obviously, as compared to groups B and C. CONCLUSION: DSHX enhances the expression of MMP-1 but decreases that of TIMP-1 in liver tissues of CCl4-induced hepatic fibrotic rats, which may result in its elevated activity that contributes to fighting against hepatic fibrosis.     

Effect of IL-10 on the expression of HSC growth factors in hepatic fibrosis rat

AIM: To study the effect of IL-10 on the expression of growth factors - transforming growth factor-β1(TGF-β1), epidermal growth factor (EGF), hepatocyte growth factor (HGF)and platelet-derived growth factor (PDGF) of hepatic stellate cells (HSCs) of hepatic fibrosis rat and the anti-fibrogenic role of exogenous IL-10. METHODS: Hepatic fibrosis was induced by CCl4 administration intra-peritoneally. Sixty clean male Sprague-Dawley (SD) rats were randomly divided into three groups: normal control group (GN, 8 rats), hepatic fibrosis model group (GC, 28 rats) and IL-10 treated group (GI, 24 rats). At the beginning of the 7th and 11th wk, rats in each group were routinely perfused with pronase E and type IV collag-enase through a portal vein catheter and the suspension obtained from the liver was spun by centrifugation with 11% Nycodenz density gradient to isolate HSCs. Histological examination was used to determine the degree of hepatic fibrosis. RT-PCR was employed to analyze mRNA expression from freshly isolated cells. Immunocytochemistry was performed to detect protein expression in primary cultured HSCs. RESULTS: Rat hepatic fibrosis was developed with the increase of injection frequency of CCl4, and HSCs were successfully isolated. At the 7th and 11th wk, TGF-β1, EGF, and HGF mRNA in GC increased obviously compared with GN (P= 0.001/0.042, 0.001/0.001, 0.001/0.001) and GI (P=0.001/0.007, 0.002/0.001, 0.001/0.001). For TGF-β1, no difference was observed between GI and GN. For EGF, mRNA level in GI increased compared with GN during the 7th wk (P=0.005) and 11th wk (P=0.049). For HGF, mRNA level in GI decreased compared with GN at the 7th wk (P=0.001) and 11th wk (P=0.021). Between these two time points, TGF-β1 expression at the 7th wk was higher than that of the 11th wk (P=0.049), but for EGF, the former was lower than the latter (P=0.022). As for PDGF mRNA, there was no significant difference between these groups, but difference seemed to exist in protein levels. Results by immunocytochemistry of TGF-β1 and EGF were paralleled with the above findings. CONCLUSION: The expression of TGF-β1, EGF and HGF increased in HSC of hepatic fibrosis rat and decreased after treatment with IL-10. IL-10 plays an anti-fibrogenic role by suppressing growth factors expression.     

Effects of augmentation of liver regeneration recombinant plasmid on rat hepatic fibrosis

AIM: To investigate the effects of eukaryotic expression of plasmid on augmentation of liver regeneration (ALR) in rat hepatic fibrosis and to explore their mechanisms. METHODS: Ten rats were randomly selected from 50 Wistar rats as normal control group. The rest were administered intraperitoneally with porcine serum twice weekly. After 8 wk, they were randomly divided into: model control group, colchicine group (Col), first ALR group (ALR1), second ALR group (ALR2). Then colchicine ALR recombinant plasmid were used to treat them respectively. At the end of the 4th wk, rats were killed. Serum indicators were detected and histopathological changes were graded. Expression of type Ⅰ, Ⅲ, collagen and TIMP-1 were detected by immunohisto-chemistry and expression of TIMP-1 mRNA was detected by semi-quantified RT-PCR. RESULTS: The histologic examination showed that the degree of the rat hepatic fibrosis in two ALR groups was lower than those in model control group. Compared with model group, ALR significantly reduced the serum levels of ALT, AST, HA, LN, PCIII and IV (P<0.05). Immunohistochemical staining showed that expression of type Ⅰ, Ⅲ, collagen and TIMP-1 in two ALR groups was ameliorated dramatically compared with model group (I collagen: 6.94±1.42,5.80±1.66 and 10.83±3.58 in ALR1, ALR2 and model groups, respectively; Ⅲ collagen: 7.18±1.95, 4.50±1.67 and 10.25±2.61, respectively; TIMP-1: 0.39±0.05,0.20±0.06 and 0.53±0.12, respectively,P<0.05 or P<0.01). The expression level of TIMP-1 mRNA in the liver tissues was markedly decreased in two ALR groups compared with model group (TIMP-1 mRNA/β-actin: 0.89±0.08, 0.65±0.11 and 1.36±0.11 in ALR1, ALR2 and model groups respectively, P<0.01). CONCLUSION: ALR recombinant plasmid has beneficial effects on rat hepatic fibrosis by enhancing regeneration of injured liver cells and inhibiting TIMP-1 expressions.     

Effects of interleukin-10 on activation and apoptosis of hepatic stellate cells in fibrotic rat liver

AIM:To study the effects of interleukin-10(IL-10)on the expression of α-smooth muscle actin(α-SMA),nuclear factor-κB(NF-κB)and Fas/Fas ligand(FasL)inhepatic stellate cells of experimental rats with hepaticfibrosis.METHODS:Sixty clean SD rats were randomly dividedinto control group(group N),liver fibrotic group(groupC)and IL-10 treatment group(group I).Control groupreceived intraperitoneal injection of saline(2ml·kg~(-1)),twicea week.Fibrotic group was injected intraperitoneallywith 50% carbon tetrachloride(CCl_4)(2 ml·kg~(-1)),twicea week.IL-10 treatment group was given IL-10 at adose of 4 μg·kg~(-1)20 minutes before CCl_4 administrationfrom the third week.Hepatic stellate cells(HSCs)wereisolated from these rats at the seventh and eleventhweeks during the course of liver fibrosis,respectively.The expression of α-SMA and NF-κB in HSCs wasmeasured by S-P immunohistochemistry.The expressionof Fas and FasL mRNA was measured by RT-PCR.Furthermore,liver tissues were harvested from threegroups at the same time.RESULTS:The CCl_4- induced experimental rat hepaticfibrosis model was established successfully.The purityof extracted hepatic stellate cells was about 95% andthe yield of hepatic stellate cells was 1.2-2.3×10~6/g livertissue averagely.The positive expression of α-SMA andNF-κB was 36.5% and 28.5% respectively in group N.The positive levels of α-SMA and NF-κB were increasedsignificantly in group C compared to group N(P<0.01).The positive signals decreased significantly(P<0.05)ingroup I.In the 11~(th)week,the HSCs of group I becameround with visible pyknotic nuclei.The expression ofNF-μB in group C was significantly increased in a time-dependentmanner(P<0.01),but there was no difference in the α-SMA expression(P>0.05).The mRNA of Fasand FasL in group C was significantly increased in a time-dependent manner compared to that in control group.After treated with IL-10,the expression level of Fas andFasL was higher in group I than in group C.CONCLUSION:The positive expression of α-SMA andNF-κB in hepatic stellate cells is decreased by ectogenicIL-10 in liver fibrosis induced by CCl_4.The expression ofFas and FasL is increased in the course of liver fibrosis,and is further increased by IL-10.IL-10 could inhibitthe activation of HSCs and cause apoptosis of activatedHSCs.     

Diagnostic value of platelet derived growth factor-BB, transforming growth factor-β1,matrix metalloproteinase-1, and tissue inhibitor of matrix metalloproteinase-1 in serum and peripheral blood mononuclear cells for hepatic fibrosis

AIM: Noninvasive diagnosis of hepatic fibrosis has become the focus because of the limited biopsy, especially in the surveillance of treatment and in screening hepatic fibrosis.Recently, regulatory elements involved in liver fibrosis, such as platelet derived growth factor-BB (PDGF-BB), transforming growth factor-β1 (TGF-β1), matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), have been studied extensively. To determine whether these factors or enzymes could be used as the indices for the diagnosis of hepatic fibrosis, we investigated them by means of receiver operating characteristic (ROC) curve.METHODS: Serum samples from sixty patients with chronic viral hepatitis B and twenty healthy blood donors were assayed to determine the level of PDGF-BB, TGF-β1, MMP-1, and TIMP-1 with ELISA, and HA, PCIII, C-IV, and LN level with RIA. The message RNA (mRNA) expression of TIMP-1 and MMP-1 in peripheral blood mononuclear cells (PBMCs) was detected by RT-PCR and Northern blot hybridization. Liver biopsy was performed in all patients.The biopsy samples were histopathologically examined. The trial was double-blind controlled.RESULTS: The serum level of PDGF-BB, TIMP-1, the ratio of TIMP-1 and MMP-1 (TIMP-1/MMP-1), mRNA expression of TIMP-1 (TIMP-1mRNA), and the ratio of TIMP-1mRNA and MMP-1mRNA (TIMP-1mRNA/MMP-1mRNA) in patients was significantly higher than those in the healthy blood donors (t=2.514-11.435, P=0.000-0.016). The serum level of PDGF-BB, TIMP-1, TIMP-1/MMP-1, and TIMP-1mRNA was positively correlated with fibrosis stage and inflammation grade (r=0.239-0.565, P=0.000-0.033), while the serum level of MMP-1 was negatively correlated with fibrosis stage and inflammation grade, and TIMP-1mRNA/MMP-1mRNA was positively correlated with inflammation grade. Through the analysis by ROC curve, serum PDGF-BB was the most valuable marker, and its sensitivity was the highest among the nine indices. The markers with the highest specificity were TIMP-1mRNA and TIMP-1mRNA/MMP-1mRNA in PBMCs. The area under the curve (AUC) of PDGF-BB, TIMP-1mRNA, TIMP-1mRNA/MMP-1mRNA, TIMP-1/MMP-1, HA,PCIII, TIMP-1, C-IV, and LN was 0.985, 0.876, 0.792, 0.748,0.728, 0.727, 0.726, 0.583, and 0.463, respectively. The sensitivity and the specificity in the parallel test was 99.0 %and 95.0 % when serum PDGF-BB, TIMP-1mRNA and TIMP1mRNA/MMP-1mRNA was detected simultaneously.CONCLUSION: Serum level of PDGF-BB, TIMP-1mRNA,TIMP-1mRNA/MMP-1mRNA in PBMCs, and serum level of TIMP-1 and TIMP-1/MMP-1 can be used as the indices for the diagnosis of hepatic fibrosis, but the former three are more useful. The combination of serum PDGF-BB, TIMP-1mRNA and TIMP-1mRNA/MMP-1mRNA in PBMCs is even more efficient in screening liver fibrosis.     

Effect of Oxymatrine on the TGFbeta-Smad signaling pathway in rats with CCl4-induced hepatic fibrosis

AIM： To explore the anti-fibrotic effect of Oxymatrine on CCl4-induced liver fibrosis in rats and its modulation on the TGFbeta-Smad signaling pathway. METHODS： One hundred healthy male SD rats were randomly divided into three groups： normal group （n = 20）, treatment group of Oxymatrine （n = 40） and CCh-induced fibrosis group （n = 40）. Experimental hepatic fibrosis was induced by subcutaneous injection of carbon tetrachloride （CCh soluted in liquid paraffin with the concentration of 300 g/L, the dosage of injection was 3 mL/kg, twice per week for 8 wk）. The treated rats received Oxymatrine via celiac injection at a dosage of 10 mg/kg twice a week at the same time. The deposition of collagen was observed with H＆E and Masson staining. The concentration of serum TGF-β1 was assayed with ELISA. The gene expression of Smads and CBP （CREB binding protein） was detected with in situ hybridization （ISH） and immunohistochemistry （IH）, respectively. All the experimental figures were scanned and analyzed with special figure-analysis software. RESULTS： A significant reduction of collagen deposition and rearrangement of the parenchyma was noted in the liver tissue of Oxymatrine-treated rats. The semi- quantitative histological scores （2.43 ± 0.47 μm^2 vs 3.76 ±0.68, P 〈 0.05） and average area of collagen/in those rats were significantly decreased when compared with hepatic cirrhosis model rats （94.41 ± 37.26 μm^2 vs 290.86 ± 89.37 μm^2, P 〈 0.05）. The gene expression of Smad 3 mRNA was considerably decreased in the treated animals. The A value of Smad 3 mRNA was lower in the treated rats than the model rats （0.034 ± 0.090 vs 0.167 ± 0.092, P 〈 0.05）. Contrarily, the A value of Smad 7 mRNA was increased considerably in the treated animals （0.175 ± 0.065 vs 0.074 vs 0.012, P 〈 0.05）. There was an obvious decrease in the expression of CBP mRNA in treated rats as illuminated by a reduction of its A value when compared with model rats （0.065±0.049 vs 0.235 ?     

Diagnostic value of platelet derived growth factor-BB, transforming growth factor-β1,matrix metalloproteinase-1, and tissue inhibitor of matrix metaUoproteinase-1 in serum and peripheral blood mononuclear cells for hepatic fibrosis

AIM: Noninvasive diagnosis of hepatic fibrosis has become the focus because of the limited biopsy, especially in the surveillance of treatment and in screening hepatic fibrosis. Recently, regulatory elements involved in liver fibrosis, such as platelet derived growth factor-BB (PDGF-BB), transforming growth factor-β1(TGF-β1), matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1), have been studied extensively. To determine whether these factors or enzymes could be used as the indices for the diagnosis of hepatic fibrosis, we investigated them by means of receiver operating characteristic (ROC) curve. METHODS: Serum samples from sixty patients with chronic viral hepatitis B and twenty healthy blood donors were assayed to determine the level of PDGF-BB, TGF-β1, MMP-1, and TIMP-1 with ELISA, and HA, PCIII, C-IV, and LNlevel with RIA. The message RNA (mRNA) expression of TIMP-1 and MMP-1 in peripheral blood mononuclear cells (PBMCs) was detected by RT-PCR and Northern blot hybridization. Liver biopsy was performed in all patients. The biopsy samples were histopatholocjically examined. The trial was double-blind controlled. RESULTS: The serum level of PDGF-BB, TIMP-1, the ratio of TIMP-1 and MMP-1 (TIMP-1/MMP-1), mRNA expression of TIMP-1 (TIMP-lmRNA), and the ratio of TIMP-lmRNA and MMP-lmRNA (TIMP-lmRNA/MMP-lmRNA) in patients was significantly higher than those in the healthy blood donors (t=2.514-11.435, P=0.000-0.016). The serum level of PDGF-BB, TIMP-1, TIMP-1/MMP-1, and TIMP-lmRNA was positively correlated with fibrosis stage and inflammation grade (r=0.239-0.565, P=0.000-0.033), while the serum level of MMP-1 was negatively correlated with fibrosis stage and inflammation grade, and TIMP-lmRNA/MMP-lmRNA was positively correlated with inflammation grade. Through the analysis by ROC curve, serum PDGF-BB was the most valuable marker, and its sensitivity was the highest among the nine indices. The markers with the highest specificity were TIMP-lmRNA and TIMP-lmRNA/MMP-lmRNA in PBMCs. The area under the curve (AUC) of PDGF-BB, TIMP-lmRNA, TIMP-lmRNA/MMP-lmRNA, TIMP-1/MMP-1, HA, PCIII, TIMP-1, C-IV, and LN was 0.985, 0.876, 0.792, 0.748, 0.728, 0.727, 0.726, 0.583, and 0.463, respectively. The sensitivity and the specificity in the parallel test was 99.0% and 95.0 % when serum PDGF-BB, TIMP-lmRNA and TIMP-lmRNA/MMP-lmRNA was detected simultaneously. CONCLUSION: Serum level of PDGF-BB, TIIVIP-lmRNA, TIMP-lmRNA/MMP-lmRNA in PBMCs, and serum level of TIMP-1 and TIMP-1/MMP-1 can be used as the indices for the diagnosis of hepatic fibrosis, but the former three are more useful. The combination of serum PDGF-BB, TIMP-lmRNA and TIMP-lmRNA/MMP-lmRNA in PBMCs is even more efficient in screening liver fibrosis.     

肝纤维化过程中胶原、基质金属蛋白酶及其抑制因子表达的动态变化及相互关系

目的研究在整个肝纤维化形成过程中肝组织Ⅰ、Ⅲ型胶原,间质性胶原酶(MMP 1 3)及其抑制因子(TIMP-1)表达水平的动态变化规律及相互间的关系.方法将大鼠随机分成正常对照组与模型组.模型组以二甲基亚硝胺腹腔内注射,第1周注射3次,随后每周2次,共注射6周,停用后再观察2周;正常对照组以等渗盐水代替腹腔内注射.分别于第1、4、10、17、28、42、56天分批处死大鼠.留取的肝脏组织做HE与Masson染色,按0～4期标准判定肝纤维化程度,测定羟脯氨酸含量,应用半定量RTPCR检测Ⅰ、Ⅲ型胶原、MMp-13和TIMP-1 mRNA.结果在肝纤维化形成过程中,胶原持续增高,其中Ⅰ型胶原mRNA在肝组织受损后10 d开始较正常对照明显增高(正常组0.468±0.015,模型组0.603±0.031,t=2.8 5,P＜0.05),并保持不断增高的表达水平直至实验结束;Ⅲ型胶原mRNA从28d左右开始显著增高(正常组0.774±0.043,模型组0.922±0.079,t=4.16,P＜0.01),直至实验结束;TIMP-1 mRNA从第4天即开始明显增高(正常组0.618±0.030,模型组0.728±0.013,t=2.60,P＜0.05),并保持不断增高的趋势直至实验结束;MMP-13 mRNA从10 d后到28 d有显著增高(17d左右达到高峰,正常组0.987±0.048,模型组1.141±0.033,t=4.08,P＜0.01),此后便逐渐下降至实验结束.结论在肝纤维化形成过程中MMP-13的表达虽有增高,但由于TIMP-1的表达在肝受损后早期即开始持续不断增高,从而MMP-13降解胶原的能力受到抑制,致使过度产生与沉积的胶原得不到有效降解,促进了肝纤维化的发展.     

Effects of interferon-alpha on expression of hepatic stellate cell and transforming growth factor-β1 and α-smooth muscle actin in rats with hepatic fibrosis

AIM: To investigate the effect of interferon-α (IFN-α) onpreventing or reversing hepatic fibrosis in rat experimental model induced by CCl4.METHODS: One hundred and ten Sprague-Dawley rats were divided into five groups: group A (normal controls, n = 18), group B (fibrotic model controls, n = 22), group C (IFN-α prevention, n = 22) initially treated with intramuscular injection of IFN-α in saline daily at the doses of 1×105 U for 6 wk, group D (IFN-α treatment, n = 24) treated with intra-muscular injection of IFN-α in saline daily atthe doses of 1×105 U for 6 wk after the first 6 wk, group E (0.9% sodium chloride treatment control, n = 24) treated with intra-muscular injection of 0.01 mL/kg daily for 6 wk after the first 6 wk. At the end of the experiment, all rats of each group were killed. Samples of the liver obtained by biopsy were subjected to histological, immunohistochemicaland electron microscopic studies for the expressions of transforming growth factor-β1 (TGF- β1) and α-smoothmuscle actin (α-SMA).RESULTS: The expressions of TGF-β1, the number of activated hepatic stellate cells and α-SMA in hepatic tissue of group C were significantly less than those of group B (P＜0.01). The degree of fibrosis score in group B was also significantly less than that of group C under light microscope (P＜0.01).CONCLUSION: IFN-α can inhibit the production of TGF-β1,decrease HSC activation and stimulate its apoptosis.     

PDGF-BB对肝星状细胞表达MMP-2及TIMP-1的影响

目的：探讨血小板衍生生长因子－BB（PDGF－BB）对体外培养大鼠肝星状细胞（HSC）表达基质金属蛋白酶－2（MM－2）及金属蛋白酶组织抑制因子－1（TIMP－1）的影响。方法：原位灌流分离HSC，体外培养激活，用PDGF－BB干预，采用半定RT－PCR方法检测各组MMP－2、TIMP－1 mRNA的表达情况。结果：PDGF－BB干预组TIMP－1 mRNA的表达较对照组明显增强（P＜0．01），且随着干预时间的延长其表达逐渐增强（P＜0．01）；而PDGF－BB干预组MMP－2表达与对照组无明显差异（P＞0．05）。结论：PDGF－BB促进肝纤维化与其引起HSC表达TIMP－1增强有关。     

Adeno-associated virus mediated interferon-gamma inhibits the progression of hepatic fibrosis in vitro and in vivo

AIM: To investigate the effects of adeno-associated virus (AAV) mediated expression of human interferon-γ for gene therapy in experimental hepatic fibrosis in vitro and in vivo. METHODS: We constructed the recombinant AAV encoding human INF-γ (rAAV- INF-γ) and took the primary rat hepatic stellate cells and carbon tetrachloride induced rats as the experimental hepatic fibrosis model in vitro and in vivo. Immunocytochemistry analysis was used to reveal the expression of α-SMA, the marker protein expressed in hepatic stellate cells. The mRNA expression of TGF-β, TIMP-1, and MMP-13 were analyzed by RT-PCR method. In vivo study, the hydroxyproline content in liver and serum AST, ALT were also detected. RESULTS: In vitro study, AAV vector could mediated efficient expression of human INF-γ, which inhibit the activation of hepatic stellate cells, decrease the expression of α-SMA and mRNA of TIMP-1, TGF-β, with the MMP-13 unchanged. In vivo study, the histological examination revealed that rAAV- INF-γ could inhibit the progression of the hepatic fibrosis. In the rAAV-INF-γ induced group, the hydroxyproline content and serum AST, ALT level were decreased to 177±28 μg/g wet liver, 668.5±140.0, 458.4±123.5 U/L, compare with the fibrosis control group 236±31 μg/g wet liver, 1 019.1±276.3, 770.5±154.3 U/L, respectively (P<0.01). mRNA expression of TIMP-1 in the rAAV-INF-γ induced rat liver was decreased while no significant change was observed in TGF-β and MMP-13. CONCLUSION: All these results indicated that rAAV-INF-γ has potential effects for gene therapy of hepatic fibrosis, which could inhibit the progression of hepatic fibrosis.     

实验性肝纤维化大鼠MMPs和TIMPs mRNA表达及中药小柴胡汤的作用

目的 探讨大鼠肝纤维化过程中MMP-2、TIMP-1 mRNA表达及小柴胡汤对其的影响.方法 用40%的四氯化碳制备大鼠肝纤维化模型,并用不同剂量的小柴胡汤进行干预.应用HE常规染色法对肝组织切片行组织病理学检查;应用逆转录聚合酶链反应法(RT-PCR)半定量测定大鼠肝组织中MMP-2、TIMP-1 mRNA的表达.结果 (1)肝组织病理学检查结果显示:小柴胡汤治疗组与模型组相比,肝纤维化程度显著减轻.(2)病理模型组TIMP-1 mRNA与正常对照组比明显升高(P＜0.01);而MMP-2 mRNA却明显降低(P＜0.05).(3)小柴胡汤治疗组TIMP-l mRNA与模型组比显著降低(P＜0.01),而MMP-2 mRNA与模型组无差异(P＞0.05).结论 TIMP-1 mRNA在肝纤维化过程中升高;小柴胡汤能显著减轻大鼠肝纤维化程度,其可能通过下调TIMP-1 mRNA的表达发挥作用.     

缺氧对肝星状细胞基质金属蛋白酶Ⅱ表达及活性调节的影响

目的 研究缺氧对ＨＳＣ基质金属蛋白酶Ⅱ（ｍａｔｒｉｘ ｍｅｔａｌｌｏｐｒｏｔｅｉｎａｓｅ－２,ＭＭＰ－２）表达及活性调节的影响。方法 大鼠ＨＳＣ体外原代培养,以免疫细胞化学及ＥＬＩＳＡ法分别检测细胞内ＭＭＰ－２及基质金属蛋白酶组织抑制因子Ⅱ（Ｔｉｓｓｕｅ ｉｎｈｉｂｉｔｏｒ ｏｆ ｍｅｔａｌｌｏｐｏｒｅｉｎａｓｅ－２,ＴＩＭＰ－２）的表达,和培养上清流中两者的相对量,并以酶图法测培养上清液ＭＭＰ－