酵母多糖对S_(180)荷瘤小鼠抗氧化作用和免疫机能的影响

Effects of Zymosan on Antioxidation and Immune Function In S_(180) Tumor-Bearing Mice

目的:研究酵母多糖(zymosan)对S180荷瘤小鼠抗氧化状态和免疫功能的影响。方法:将昆明小鼠70只随机分为7组,第1组作为正常组,另6组将S180瘤细胞悬液接种于小鼠右前肢腋皮下制备荷瘤小鼠动物模型,分为zymosan低、中、高剂量组和环磷酰胺(Cy)组、肿瘤对照组及zymosan联合Cy治疗组,灌胃第7 d接种S180瘤,第19 d后测定小鼠肝匀浆中丙二醛(MDA)含量、谷胱甘肽过氧化酶(GSH-Px)和超氧化物歧化酶(SOD)活力,评价zymosan对小鼠抗氧化能力的作用。采用逆转录-聚合酶链反应(RT-PCR)检测IL-2、TNF-α、TGF-β1mRNA的表达,评价zymosan对小鼠免疫功能的影响。结果:zymosan各剂量组均能提高肝脏中GSH-Px活性和SOD活力,但zymosan高剂量组显著降低MDA水平(P<0.01)。zymosan各剂量组荷瘤小鼠肿瘤组织内TNF-α、IL-2 mRNA相对表达量明显高于Cy组和肿瘤对照组(P<0.01),同时下调TGF-β1水平。zymosan高剂量对小鼠S180瘤有明显抑制作用,且与Cy合用后有协同作用,并提高了小鼠的TNF-α、IL-2 mRNA的表达。结论:zymosan的抑瘤机制可能主要是抗氧化作用和免疫调节作用,且作用与剂量有关。

To study the effects of zymosan on antioxidation and immune function in S180 tumor- bearing mice, 70 Kunming mice were divided into 7 groups randomly. One group was the normal group, the others were divided into 6 groups randomly after S180 tumors - bearing mice mode was established by the inoculation of cancer cell suspension subcutaneously in mice＇s right anterior limbs. The mice were divided into low, medium and high dose zymosan groups, cyclophosphane（Cy） group, tumor control group and zymosan combination Cy group. At the 7th day S180 cancer cell suspension was transplanted in six groups, MDA, GSH -Px and SOD activity in liver homogenate at 19th day were analyzed to estimate the antioxidation effect of zymosan. RT -PCR（ reverse transcription polymerase chain reaction）was used to detect the mRNA expression of IL -2, TNF -α and TGF -β1 to appraise zymosan influence on S180 tumor - bearing mice immune function. Zymosan groups increased the activities of GSH - Px and SOD activity in the liver, levels of S180 tumor - only high dose zymosan groups reduced the levels of MDA（P 〈0.01 ）. The mRNA expression beating mice tumor tissue TNF - α and IL - 2 were higher obviously in the zymosan group than that in the Cy group and tumor control group（P 〈0.01 ）, and down- regulated level of TGF -β1. The high dose zymosan conspicuously possessed a depressant effect on S180 tumor and joint action with combination Cy and enhancement of the mRNA expression of TNF - α, IL - 2 of mice. The mechanism of tumor - inhibition by zymosan is mainly due to enhancing the immune and antioxidation function, and furthermore, the effect is dose dependent.