大豆异黄酮体外对大鼠淋巴细胞激活和天然杀伤细胞活性的作用(英文)

目的 :研究大豆异黄酮对大鼠免疫细胞的体外作用。方法 :取大鼠抗凝血 ,密度梯度离心法分离外周血单个核细胞 ,以伴刀豆球蛋白A(ConA)和体内所能达到的不同浓度的金雀异黄素或大豆苷元共同孵育 6 8h后 ,四唑蓝还原法 (MTT)测定体外ConA诱导的淋巴细胞增殖 ;另取外周血单核细胞为效应细胞 ,YAC 1细胞为靶细胞 ,以乳酸脱氢酶法测定天然杀伤细胞 (NK )活性。结果 :在 0 .0 1～ 1μmol·L- 1浓度范围内 ,大豆苷元可剂量依赖性的增强体外ConA诱导的淋巴细胞增殖 (P <0 .0 1) ,1μmol·L- 1的大豆苷元可明显增强NK细胞活性 (P<0 .0 1)。而同样浓度范围内的金雀异黄素对淋巴细胞增殖及NK细胞活性均无明显作用。结论 :大豆苷元体外能剂量依赖性的刺激ConA诱导的淋巴细胞转化 ,增强NK细胞活性 ,这种增强的免疫功能可能是大豆制品抗肿瘤作用的机制之一

Effects of soy isoflavones on lymphocyte activation and natural killer cells activity in vitro of rats(in English)

AIM: To study the effects of soy isoflavones on immunocytes of rats in vitro. METHODS: Peripheral blood mononuclear cells were obtained from Wistar rats and were cocultured with ConA and various concentrations of genistein or soy daidzein (daidzein) for 68 h. The proliferation of lymphocytes stimulated by ConA in vitro was determined by tetrazolium assay (MTT). In another experiment, isolated peripheral blood mononuclear cells and YAC-1 cells were used as effector cells and target cells, respectively. Natural killer cells (NK) activity was evaluated by lactic dehydrogenase (LDH) assay. RESULTS: Daidzein significantly increased ConA-induced lymphocytes proliferation in a concentration-dependent manner (0.01-1 μmol*L-1) in comparison with ConA-induced vehicle control(P<0.01). In addition, 1 μmol*L-1 daidzein significantly enhanced NK activity(P<0.01). There was no significant effect on the proliferation of lymphocytes and NK activity cocultured with genistein within the same dosing regimens. CONCLUSION: Daidzein, rather than genistein, is able to enhance the immunological function in vitro, which suggests a novel approach to understanding the action mechanisms of daidzein by which soy foods may contribute to observed cancer prevention.