熊胆粉对DEN + PBO诱发大鼠肝癌早期阶段的影响研究

Effects of bear bile powder on the early stage of hepatocarcinogenesis induced by DEN+PBO in SD rats

目的 为了解明熊胆粉在肝癌早期阶段的抑制作用,利用大鼠短期致癌模型进行了熊胆粉(bear bile powder, BBP)的抗癌药效实验。方法 40只5周龄雄性SD大鼠分成4组:DEN单独组(DEN-alone),模型组(DEN+PBO),低剂量组(DEN+PBO+BBP-L)(200 mg/kg),高剂量组(DEN+PBO+BBP-H)(400 mg/kg)。实验开始时,大鼠腹腔注射200 mg/kg二乙基亚硝胺(diethylnitrosamine, DEN),模型组、低剂量组及高剂量组动物饲喂了0.5%胡椒基丁醚(piperonyl butoxide, PBO)粉末饲料。低剂量组和高剂量组动物同时灌胃200或400 mg/kg BBP 8周。结果 饲喂PBO粉末饲料的动物绝对及相对肝重量显著大于DEN单独组。但是,DEN+PBO+BBP-L组的GST-P阳性病灶的数量和面积与DEN+PBO组相比显著减少。同时,因DEN和PBO处理显著增加的Ki-67阳性细胞率在BBP处理组显著减少。但是,细胞周期相关的Ccne1、Cdkn1b和细胞凋亡相关的Caspase 8、Caspase 9仅在DEN+PBO+BBP-H组中显著增加,在DEN+PBO+BBP-L组中没有变化。结论 BBP在肝癌形成早期阶段通过抑制癌前病灶发挥抑制作用,且它的抗癌机制中包含着抑制细胞增殖活性和诱导细胞凋亡作用。同时,高剂量的BBP可能影响其抗癌前病灶作用。

Objective Bear bilepowder(BBP),anatural Traditional Chinesemedicine,hasantioxidant and anticancer effects.To clarify the effect of BBP on the early period of hepatocarcinoma formation,we conducted anticancer efficacy experiments using short-term carcinogenesis bioassay models.Methods Forty 5-week-old male SD rats were randomly divided into DEN-alone,DEN+PBO,DEN+PBO+BBP-L(20O mg/kgBBP),andDEN+PBO+BBP-H(400 mg/kg BBP)groups,with 10 animals per group.All rats were injected intraperitoneally with 200 mg/kg DEN,and the last three groups were provided a diet containing 0.5%PBO.Additionally,rats of the last two groups were orally administered 200 or 400 mg/kg BBP for 8 weeks.Results The relative and absolute liver weights of PBO-treated groups were significantly increased compared with those of the DEN alone group.However,the number and area of GST-P*foci were significantly decreased in the DEN+PBO+BBP-L group compared with the DEN+PBO group.Additionally,the Ki-67*cell ratio was significantly increased by DEN and PBO,and significantly decreased by BBP in both BBP-treated groups.Interestingly,the mRNA levels of Ccnel and Cdknlb related to the cell cycle and Caspase 8 and Caspase 9 related to apoptosis were significantly increased in the DEN+PBO+BBP-H group.However,these changes were not observed in the DEN+PBO+BBP-L group.Conclusions BBP has a suppressive effect on the early period of hepatocarcinoma formation,leading to inhibition of preneoplastic lesions.Additionally,the suppression mechanism of BBP involves inhibition of cell proliferation and induction of apoptosis.A high dose of BBP may influence its inhibitory effect on preneoplastic lesions.