| Breviscapine have a variety of pharmacological effects, such as scavenging free radicals, antioxidation, antibacterial, antithrombus. In previous study, we found that breviscapine could suppress TGF-β1, the present study was to investigate antifibrosis and antitumor of breviscapine and its possible mechanisms.MTT assay was used to detect the proliferation of rats hepatic stellate cells, T lymphocyte and K562 cancer cell lines; Antifibrosis of breviscapine was evaluated by CCl4-induced liver fibrosis model and bleomycin-induced lung fibrosis model in mice, we examined the activity of antioxidant enzymes (such as POD, CAT, SOD) and the level of TGF-β1, TNF-αand MDA in fibrotic tissues and serum, and carried out histopathologic evaluation in both models. The subcutaneous xenograft and metastatic Lewis lung cancer models were used to evaluate the tumor inhibition of breviscapine alone and combined with radiotherapy or chemotherapy. The subcutaneous xenograft 4T1 breast cancer model was used to observe whether breviscapine could prevent the tumor recurrence and metastasis after surgical resection.In vitro, 1-50μmol/L of breviscapine could promote mouse spleen lymphocyte proliferation, the optimal concentration was 5 to 10μmol/L. The cell morphology, lactate dehydrogenase release and cell proliferation were not significantly affected by breviscapine. However, breviscapine could inhibit TGF-β1-induced HSC proliferation, IC50 was 22.04μmol/L (95% confidence interval 13.94 to 34.19μmol/L). Breviscapine 100μg/ml could inhibit the growth of K562 cells, whereas it had no significant effect on lymphocyte at 10 to 100μg/ml. Breviscapine could enhance doxorubicin resistance to lymphocyte and doxorubicin-induced growth inhibition in k562 cells. In addition, 10 or 30μg/ml of breviscapine could significantly enhance doxorubicin-induced apoptosis of K562 cells.In vivo, ALT and AST in breviscapine group (218.22U/L and 247.81U/L) was smaller than those of in model group(571.35U/L and 514.52U/L, respectively) in CCl4-induced liver fibrosis model, versus 56.73U/L and 139.27U/L in normal control group. Breviscapine ig100mg/kg could inhibit activity of Hydroxyproline, Collagen, MDA and TGF-β, but increase activity of POD, CAT, total SOD, Cu-Zn SOD in liver tissue and serum. Similar, breviscapine ig100mg/kg could increase activity of POD, CAT, total SOD, Cu-Zn SOD in bleomycin-induced lung fibrosis model. Hydroxyproline, Collagen, MDA and TGF-βof lung tissue and serum in model group increased significantly compared with normal group, whereas they in breviscapine group were much lower than those in model group.Breviscapine alone had not only suppressed orthotopic tumor growth and lung metastasis but also enhanced survial in the subcutaneous xenograft and metastatic Lewis lung cancer models. Surprisedly, it combined with radiotherapy or chemotherapy not only showed synergistic anti-tumor, but also suppressed or even eliminated the hematopoietic system damage of radio-/ chemo-therapy. In addition, the result showed that recurrence and metastasis rate of tumor in breviscapine group(20% and 20%) was lower than those of in model group(50% and 70%, respectively) in 4T1 breast subcutaneous carcinoma after surgical resection.Further study showed that breviscapine could increase T cell proliferation induced by ConA. Breviscapine increased percentage of spleen lymphocyte expressing cytokines including IFN-γand IL-2, reduced TGF-β1 and IL-4. Further more, breviscapine could obviously enhance cytochrome C release, caspase-8 andcaspase-3 activation in K562 cells which were caused by doxorubicin, upregulate radio of p53/bcl-2 expression, and increase cell apoptosis.In conclusion, our results indicated that breviscapine as a TGF-β1 inhibitor could prevent tissue fibrosis and reverse tumor-induced immunosuppression in mice. Especially, breviscapine had synergistical antitumor effect with radiotherapy, improved therapeutic index of chemotherapeutic agents for tumor by inhiting TGF-β1 and activating tumor cell apoptosis signal way.
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