Expression of exogenous rat collagenase in vitro and in a rat model of liver fibrosis

Does Curcuma longa root powder have an effect against CCl4-induced hepatotoxicity in rats: a protective and curative approach

This study was conducted to investigate potentially protective and curative effects of Curcuma longa root (turmeric) powder on CCl₄-induced hepatotoxicity in rats. Turmeric was administered before (preventive effect) or after (curative effect) treatment with CCl₄. Total phenolic and flavonoid levels were 26.35 mg GAE/g and 12.35 mg CE/g, respectively. Using HPLC analysis, turmeric powder was rich in curcumin (62.97%), demethoxycurcumin (20.86%) and bisdemethoxycurcumin (16.17%). Curcuma longa powder showed important in vitro antioxidant activities. Results showed that the activities of aspartate aminotransaminase and alanine aminotransaminase, and the levels of bilirubin and serum lipids were increased in CCl₄-treated animals. However, total protein and albumin levels and antioxidant enzyme activities were decreased. Turmeric administration, before or after CCl₄ treatment, significantly decreased the activities of marker enzymes and lipid levels in serum. Moreover, total protein and albumin contents were restored to nearly normal levels after turmeric administration accompanied with increase of antioxidant enzymes activities.

Effects of small interfering RNA-mediated downregulation of the Krüppel-like factor 4 gene on collagen metabolism in human hepatic stellate cells

The nuclear transcription factor Krüppel-like factor 4 (KLF4) has an important role in cellular biological processes. However, the influence of KLF4 on collagen metabolism remains to be elucidated. In the present study, the effects and underlying mechanism of action of KLF4 on collagen metabolism was investigated in human hepatic stellate cells (HSC), by downregulating KLF4 expression using small interfering RNA (siRNA). The effects of KLF4 silencing by three predesigned siRNAs (siRNA1‑3) were evaluated using both reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blotting in the human LX2 HSC line. The mRNA expression levels of KLF4 were decreased by ~34, 40, and 69% in the siRNA1, siRNA2, and siRNA3 groups, respectively, as compared with the control group. These results were concordant with the protein expression levels of KLF4, as determined by western blot analysis. In the siRNA3 group, the quantity of type Ⅰ and type III collagen, and the expression levels of collagen metabolism proteins including matrix metalloproteinase‑1 (MMP‑1) and tissue inhibitors of metalloproteinases‑1 (TIMP‑1), were determined using both RT‑qPCR and western blotting. Both the mRNA and protein expression levels of type I and type III collagen were significantly decreased in the siRNA3 group, as compared with the control group. The mRNA and protein expression levels of TIMP‑1 were also significantly reduced in the siRNA3‑treated cells, whereas the mRNA and protein expression levels of MMP‑1 were significantly upregulated. Furthermore, KLF4 gene silencing significantly decreased the expression levels of numerous cytokines, including transforming grow factor‑β1, tumor necrosis factor‑α, and interleukin‑1β. The results of the present study provide evidence of siRNA‑mediated silencing of KLF4 expression, which may promote extracellular matrix (ECM) degradation, and inhibition of ECM synthesis. Therefore, KLF4 may be a promising target for the development of novel antifibrotic therapies.

Caffeine protects against alcohol-induced liver fibrosis by dampening the cAMP/PKA/CREB pathway in rat hepatic stellate cells

Alcoholic liver fibrosis (ALF) is characterized by hyperplasia of extracellular matrix under long-term alcohol stimulation. Hepatic stellate cell (HSC) activation plays an important role in promoting hepatic fibrogenesis. Caffeine, as the main active component of coffee and tea, was widely consumed in daily life. It was always a thought that caffeine can reduce the probability of suffering from liver diseases. In this study, we attempt to validate the hypothesis that caffeine inhibits activation of HSCs which were isolated from rat ALF model. The rats were gavaged by ethanol to establish ALF model and then treated with different concentrations of caffeine or colchicine. Serum was collected to measure the contents of serum alanine aminotransferase (ALT), aspartate transaminase (AST), hyaluronic acid (HA), laminin (LN), N-terminal peptide of type III procollagen (PIIINP) and type IV collagen (CIV). Then liver tissues were obtained for hematoxylin-eosin staining and Sirius-red staining. Others were treated through liver perfusion to isolate primary rat HSCs. Interestingly, we found that caffeine significantly decreased ALT, AST, HA, LN, PIIINP and CIV levels and reversed liver fibrosis in rat ALF models. Results of immunohistochemistry, real-time PCR and western blot indicated that caffeine could reduce fibrosis and inhibit cAMP/PKA/CREB signal pathway in HSC. Caffeine has a preventive effect on ALF. The mechanism may be interpreted that caffeine inhibits the cAMP/PKA/CREB signal pathway through adenosine A2A receptors in HSC.

Inhibitory effect of bone morphogenetic protein-7 on hepatic fibrosis in rats

AIM

Hepatic cirrhosis is a serious clinical problem caused by the accumulation of extracellular matrix, which can ultimately progress into hepatic failure. Transforming growth factor-beta1 (TGF-β1) plays a pivotal role in extracellular matrix production. Bone morphogenetic protein-7 (BMP-7), as a member of the TGF-β1 superfamily, has been well proved to be capable of reversing renal fibrosis in mice. In this study, we aim to investigate the potential effect of BMP-7 on hepatic fibrosis in rats.

METHODS

Sprague-Dawley rats were randomly divided into five groups. In the hepatic fibrosis model group (n=8), rats was treated with porcine serum at 0.5 ml each time, twice a week. In the negative control group (n=10), rats were intraperitoneally injected with equal amount and frequency saline. Rats were injected with BMP-7 (100 μg/kg weight) before porcine serum intraperitoneal injection in the preventive group (n=9). For the early (n=10) and late (n=8) treatment group, rats were received with BMP-7 (100 μg/kg weight) every other day since the second and fourth week respectively after porcine serum injection. After eight weeks, the degree of liver fibrosis in rats was evaluated and the expression of TGF-β1 in liver tissues was detected by Western blot and immunohistochemistry.

RESULTS

The grade of hepatic fibrosis was significant attenuated by BMP-7 prevention and treatment compared with the rats in negative control group (P<0.05). In addition, the expression of TGF-β1 greatly decreased in the BMP-7 preventive and treatment groups detected by both Western blot and immunohistochemistry.

CONCLUSIONS

BMP-7 can attenuate and even prevent the level of hepatic fibrosis in rats through inhibiting the expression of TGF-β1 in the liver fibrotic tissues. Therefore, it may be a potential clinical drug for the prevention and treatment of hepatic fibrosis.

Potential antifibrotic effects of AT1 receptor antagonist, losartan, and/or praziquantel on acute and chronic experimental liver fibrosis induced by Schistosoma mansoni

1. This study investigates the potential antifibrotic effect of losartan, AT-1 receptor antagonist, and/or praziquantel (PZQ) on acute and chronic hepatic fibrosis induced by Schistosoma mansoni (S. mansoni). 2. Schistosoma mansoni-infected mice were in two batches (I & II), each in four groups: (i) Infected untreated; (ii) treated with losartan, starting from the 4th or 12th weeks post-infection (PI); (iii) treated with PZQ in the 7th week PI; and (iv) treated with losartan, as group (ii) plus PZQ as group (iii). Comparable groups of uninfected mice were run in parallel with infected groups. Mice of batches I and II were killed 10 and 18 weeks PI, respectively. Hepatic content of hydroxyproline (HYP), serum levels and tissue expression of matrix metalloproteinase-2 (MMP-2), and transforming growth factor-β1 (TGF-β1) were determined. Parasitological, biochemical and histological parameters, which reflect disease severity and morbidity, were examined. 3. Losartan alone caused a considerable decrease in worm burden, hepatic tissue egg load with an increase in percentage of dead eggs, modulation of granuloma size and regression of inflammatory reactions, which was less obvious in the chronic stage. The best results were obtained when losartan was co-administered with PZQ, especially in the acute stage. This was revealed by a remarkable reduction in serum levels and tissue expression of MMP-2, TGF-β1 and HYP content, accompanied by conservation of hepatic reduced glutathione (GSH) versus the PZQ-treated group. 4. In conclusion, losartan has a promising antifibrotic action and could be introduced as a therapeutic tool with PZQ especially in acute schistosomal hepatic fibrosis.

Pharmacodynamics of pentoxifylline and/or praziquantel in murine schistosomiasis mansoni

Pentoxifylline (PTX) was proved to exert both anti-inflammatory and anti-fibrotic effects, and was used therapeutically in this experimental model to investigate its role alone or with praziquantel (PZQ) in Schistosoma mansoni-infected mice, and to explore its impact on the tissue expression of transforming growth factor-beta1 (TGF-beta1). S. mansoni-infected mice were divided into seven groups: Control untreated (I), treated with curative dose of PZQ, 500 mg/kg/day for 2 consecutive days (II), or subcurative dose, 100 mg/kg/day for 2 consecutive days (III), treated with PTX (10 mg/kg/day for 5 days/wk) alone for 4 weeks (IV) or in addition to subcurative dose of PZQ (V), and treated with PTX alone for 8 weeks (VI) or in addition to subcurative dose of PZQ (VII). All animals were killed 10 weeks post infection. Parasitological assessment of worm burden, tissue egg load and oogram pattern was carried out. The degree of granulomatous fibrosis and eosinophilic cell population was quantified in Sirius-red-stained sections and tissue transforming growth factor beta-1 expression was estimated immunohistochemically. Serum ALAT and GGT, as well as hepatic content of reduced GSH, were measured. The results revealed the highest percent of worm reduction and dead ova in groups (II) and (VII) accompanied by significant diminution in granulomatous parameters, collagen content and TGF-beta1 tissue expression. Moreover, treatments with PTX and/or PZQ ameliorated the liver functions. In conclusion, prolonged treatment with PTX has a potent anti-fibrogenic role especially when used in the early stages of infection, with limited toxic effects on schistosome worms and eggs. Thus, PTX can be used as an adjuvant therapeutic tool with anti-helminthic drugs in the treatment of human schistosomiasis.

Relationship between transforming growth factor β1 and anti-fibrotic effect of interleukin-10

AIM: To study the effect of interleukin-10 (IL-10) on the expression of transforming growth factor β1 (TGF-β1) in hepatic fibrosis rats and the anti-fibrotic role of exo-genous IL-10.

METHODS: Hepatic fibrosis was induced by carbon tetrachloride administered (CCl₄) intraperitoneally. The experiment was performed in two stages. In the first stage, 60 SD rats were divided randomly into normal control group 1(GN₁, n = 8), hepatic fibrosis group(GC, n = 28)and IL-10 intervened group(GI, n = 24). At the beginning of the 7^th and 11^th wk, hepatic stellate cells (HSCs) were isolated, reverse transcription-polymerase chain reation (RT-PCR) and immunocytochemistry were performed to detect the expression of TGF-β1 in HSCs. Histological examination was used to determine the degree of hepatic fibrosis. In the second stage, 47 SD rats were divided randomly into normal control group 2(GN₂, n = 6)and CCl₄ group(GZ, n = 41). At the end of the 9th week, rats in GZ group were allocated randomly into model group(GM, n = 9), IL-10 treatment group(GT, n = 9)and recovered group(GR, n = 9). At the end of the 12^th week, all rats were sacrificed. RT-PCR and immunohistochemistry were performed to detect the expression of TGF-β1 in liver tissue. ELISA was used to assay serum TGF-β1 levels.

RESULTS: Hepatic fibrosis developed in rats with the increase of the injection frequency of CCl₄. In the first stage, hepatic fibrosis developed and HSCs were isolated successfully. At the 7^th and 11^th week, TGF-β1 mRNA in GC group increased significantly compared with that in GN₁(P = 0.001/0.042)and GI groups(P = 0.001/0.007), whereas there was no significant difference between the two groups. The levels of TGF-β1 at the beginning of the 7^th wk was higher than that of the 11^th wk(P = 0.049). Immunocytochemistry results of TGF-β1 were consistent with the above findings. In the second stage, TGF-β1 increased significantly in GM group compared to GN₂. After treatment with IL-10, TGF-β1 declined obviously. The expression of TGF-β1 decreased in GR group but was still higher than that in GT group.

CONCLUSION: The levels of TGF-β1 are increased in hepatic fibrosis rats and decreased after treatment with exogenous IL-10. IL-10 may play an anti-fibrotic role by suppressing TGF-β1 expression.

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-α, 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-α, 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.

Construction of prokaryotic expression system of TGF-β1 epitope gene and identification of recombinant fusion protein immunity

AIM: To insert the constructed TGF-β₁ epitope gene into the el loop of C-terminus of truncated hepatitis B core antigen to increase TGF-β₁ antigenicity in its prokaryotic expression system and to identify immunity of the expressed recombinant protein in order to exploit the possibility for obtaining anti- TGF-β₁ vaccine.

METHODS: The TGF-β₁ encoding epitope gene (the mature TGF-β₁ from 78-109 amino acid residues, TGF-β₁³²) was amplified by polymerase chain reaction from the recombinant pGEM-7z/ TGF-β₁³² vector. The HBcAg gene fragments (encoding HBcAg from 1-71 and 89-144 amino acid residues) were amplified from PYTA1-HBcAg vector. The recombinant vector pGEMEX-1 was used to insert HBcAg1-71, TGF-β₁³² and HBcAg89-144 into restrictive endonuclease enzyme and ligated with T₄ ligase. The fusion gene fragments HBcAg1-71-TGF-β₁³²- HBcAg89-144 were recloned to pET28a(+) and the DNA sequence was confirmed by the dideoxy chain termination method. The recombinant vector pET28a (+)/CTC was transformed and expressed in E. coli BL21 (DE3) under induction of IPTG. After purification with Ni⁺²-NTA agarose resins, the antigenicity of purified protein was detected by ELISA and Western blot and visualized under electron microscope.

RESULTS: Enzyme digestion analysis and sequencing showed that TGF-β₁ epitope gene was inserted into the el loop of C-terminus of truncated hepatitis B core antigen. SDS-PAGE analysis showed that relative molecular mass (Mr) of the expressed product by pET28a (+)/CTC was Mr 24 600.The output of the target recombinant protein was approximately 34.8% of the total bacterial protein, mainly presented in the form of inclusion body. Western blotting and ELISA demonstrated that the fusion protein could combine with anti-TGF-β₁ polyclonal IgG but not with anti-HBcAg. The purity of protein was about 90 % and the protein was in the form of self-assembling particles visualized under electron microscope. This fusion protein had good anti-TGF-β₁ antigenicity and could be used as anti-TGF-β₁ vaccine.

CONCLUSION: A recombinant prokaryotic expression system with high expression efficiency of the target TGF-β₁ epitope gene was successfully established. The fusion protein is in the form of self-assembling particles and HBcAg can increase the antigenicity of TGF-β₁. The expressed TGF-β₁ epitope gene shows good immunogenicity and antigenicity.

Impaired spermatogenesis and male fertility defects in CIZ/Nmp4-disrupted mice

CIZ (Cas interacting zinc finger protein), also called Nmp4 (nuclear matrix protein 4), is a nucleo-cytoplasmic shuttling transcription factor that regulates the expression of collagen and matrix metalloproteinases. CIZ/Nmp4 was originally cloned by its binding to p130(Cas), a focal adhesion protein, and was recently shown to suppress BMP2 (bone mophogenetic protein 2) signalling. To explore the physiological role of CIZ/Nmp4, we disrupted CIZ/Nmp4-gene by inserting beta-galactosidase and neomycin resistance genes into the 2nd exon of CIZ/Nmp4-gene, which is utilized by all the sequenced alternative forms. CIZ-/- mice were born and grew to adulthood. Although they tend to be smaller than wild-type mice, no pathological abnormality was observed except in the testis. Histological analysis of the testes revealed variable degrees of spermatogenic cell degeneration within the seminiferous tubules of CIZ-/- mice, resembling the histology of the 'Germinal-cell aplasia with focal spermatogenesis'. Some of the CIZ-/- male mice developed infertility. TUNEL assay on testis sections revealed an increased occurrence of apoptosis of spermatogenic cells in the testes of CIZ-/- mice. CIZ/Nmp4 was co-localized with Smad1 in the testis, suggesting that a disregulation of BMP signalling could cause these phenotypes. These results suggest that CIZ/Nmp4 plays roles in the progress and the maintenance of spermatogenesis.

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Gene expression profiles in liver cirrhosis and normal liver tissues

AIM: To describe liver specific gene expression profiles and to identify genes with differential expression between liver cirrhotic tissues and normal liver tissues.

METHODS: The cDNA probes which were labeled with α-³²P dATP were synthesized from total RNAs of liver cirrhosis and normal liver tissues and hybridized to two identical Atlas human cDNA expression arrays membranes containing 588 known genes respectively.

RESULTS: Autoradiographic results were analyzed by specific AtlasImage^TM (version1.01a) software. Among the 588 genes analyzed, 17 genes were found up-regulated in cirrhosis, including integrin beta 7 and collagen type XVIII, and 98 genes were down-regulated in cirrhosis, including TFDP2, BAK and ABL. Expression of the genes was associated with the regulation of cell proliferation, apoptosis, differen-tiation, cell-cell interaction, invasion regulators and cytokines altered.

CONCLUSION: The results obtained from Atlas microarray provide a comprehensive liver cirrhosis specific expression profile. These results may be helpful for identification of target genes for diagnosis and designing rational therapeutic strategies.

Glutathione regulates transforming growth factor-beta-stimulated collagen production in fibroblasts

Transforming growth factor-beta (TGF-beta) is a potent fibrogenic cytokine. The molecular mechanism underlying TGF-beta fibrogenesis, however, has not been completely elucidated. In this study, we showed that TGF beta decreased the intracellular GSH content in murine embryo fibroblasts (NIH 3T3), which was followed by an increase in collagen I mRNA content and collagen protein production. Prevention of GSH depletion with N-acetylcysteine (NAC), GSH, or GSH ester abrogated TGF-beta-stimulated collagen production, whereas a decrease in intracellular GSH content with L-buthionine-S,R-sulfoximine, an inhibitor of de novo GSH synthesis, enhanced TGF-beta-stimulated collagen production. These results suggest that GSH depletion induced by TGF-beta may mediate TGF-beta-stimulated collagen production. In addition, we showed that TGF-beta stimulated superoxide production and increased release of H2O2 from the cells, whereas GSH ester decreased basal and TGF-beta + glucose oxidase-stimulated H2O2 release. H2O2, exogenously added or continuously generated by glucose oxidase, enhanced TGF-beta-stimulated collagen production, whereas suppression of superoxide production by diphenyliodonium, an NAD(P)H oxidase inhibitor, blocked TGF-beta-stimulated collagen production. These data further suggest that reactive oxygen species are involved in TGF-beta-stimulated collagen production and that the effect of GSH depletion on TGF-beta-stimulated collagen production may be mediated by facilitating reactive oxygen species signaling.

Protective effects of Rhodiola sachalinesis A Bor on CCl4-induced liver fibrosis in rats

AIM

To study the protective effects of Rhodiola schalinensis A Bor on CCl4-induced liver fibrosis.

METHODS: Male SD rats were divided into 3 groups: normal(N), Rhodiola sachalinesis A Bor(R) and model(M) group. The M and R group were given 300 ml/L CCl₄(3ml/kg, 2 times/week) for 15 weeks and Rhodiola sachalinesis A Bor (0.5g/kg, p.o., daily for 15 weeks) was administered to rats of R group. Histopathological changes were examined. The changes of hepatic content of hydroxyproline and expression of α1(Ⅰ)mRNA were observed.

RESULTS

Rhodiola sachalinesis A Bor decreased the hepatic content of hydroxyproline (657±74 μg/g vs 1 257±98 μg/g, P<0.05) and severity of hepatic fibrosis, improved the liver histopathological changes and inhibited the expression of α1(Ⅰ) mRNA and decreased the level of HA, CⅣ, PCⅢ and TGFβ1 (164±46 μg/L, 97±15 μg/L, 289±76 μg/L, 60±20 mg/L vs 265±98 μg/L, 160±30 μg/L, 456±113 μg/L, 89±23 mg/L. P<0.05, P<0.01).

CONCLUSION

Rhodiola sachalinesis A Bor is effective in protecting against CCl4-induced liver fibrosis in rats, its machenisms appear to be associated with the inhibition of collagen production and protection of hepatic cells.

Expression of insulin-like growth factor 1 and insulin-like growth factor 1 receptor and its intervention by interleukin-10 in experimental hepatic fibrosis

AIM

To study the expression of IGF-1 and IGF-1R and its intervention by interleukin-10 in the course of experimental hepatic fibrosis.

METHODS

Hepatic fibrosis was induced in rats by carbon tetrachloride intoxication and liver specimens were taken from the rats administered CCl4 with or without IL-10 treatment and the animals of the control group. Immunoreactivities for insulin-like growth factor-1 (IGF-1) and IGF-1 receptor(IGF-1R) were demonstrated by immunohistochemistry, and their intensities were evaluated in different animal groups.

RESULTS

The positive levels for IGF-1 and IGF-1R were increased with the development of hepatic fibrosis, with the positive signals localized in cytoplasm and/or at the plasmic membrane of hepatocytes. The positive signals of IGF-1 and IGF-1R were observed more frequently (P<0.01) in the CCl4-treated group (92.0 % and 90.0 %) compared to those in the control group. The positive signals decreased significantly (P<0.05) in IL-10-treated group. The responses in IGF-1 and IGF-1R expression correlated with the time of IL-10 treatment.

CONCLUSION

The expression of IGF-1 and IGF-1R immunoreactivities in liver tissue seems to be up-regulated during development of hepatic fibrosis induced by CCl(4), and exogenic IL-10 inhibits the responses.

Effects of pentoxifylline on the hepatic content of TGF-β1 and collagen in Schistosomiasis japonica mice with liver fibrosis

AIM: To study the effects of pentoxifylline (PTX) on the content of hepatic TGF-β1, type I and type III collagen in schistosomiasis japonica mice with liver fibrosis and its mechanism of anti-fibrosis.

METHODS: Forty mice with schistosomiasis were divided into four groups: one group as control without any treatment, other three were treated with Praziquantel 500 mg/(kg·d)for 2 d, high dose PTX 360 mg/(kg·d) for 8 wk, and low dose PTX 180 mg/(kg·d) for 8 wk respectively. Immunohistochemical technique and multimedia color pathographic analysis system were applied to observe the content change of hepatic TGF-β1, type I and type III collagen in schistosomiasis japonica mice with liver fibrosis before and after PTX treatment.

RESULTS: Effects of PTX on the content change of hepatic TGF-β1, type I and type III collagen in schistosomiasis japonica mice with liver fibrosis were related to the dosage of PTX, high dose PTX treated group could significantly reduce the content of TGF-β1 (0.709 ± 0.111), type I (0.644 ± 0.108) and type III (0.654 ± 0.152) collagen compared with those of control group (0.883 ± 0.140, 0.771 ± 0.156, 0.822 ± 0.129) with statistical significance (P < 0.05). Low dose PTX could also reduce the hepatic content of TGF-β1 (0.752 ± 0.152), type I (0.733 ± 0.117) and type III (0.788 ± 0.147) collagen, but without statistical significance (P > 0.05). Both high dose and low dose PTX groups have significant differences on the content of TGF-β1, type I and type III collagen (P < 0.05, P < 0.05, P < 0.01, respectively).

CONCLUSION: High dose of PTX treatment could reduce the content of hepatic TGF-β1, type I and type III collagen significantly in schistosomiasis japonica mice with liver fibrosis, and thus plays its role of antifibrosis.