石斛水溶性多糖的抗肿瘤作用及其机制的研究

目的观察石斛水溶性多糖（solub le polysaccharides fromDendrobium candidum,SPD）对在体肿瘤和离体培养肿瘤细胞的抑制作用,探讨其抑制作用的可能机制。方法观察SPD对小鼠接种肉瘤（S180）瘤体生长,离体培养人肝肿瘤细胞（SMMC27721）生长的抑制作用;分析小鼠外周血中超氧物歧化酶活性（superoxide d ismutase,SOD）和膜脂过氧化产物丙二醛（m alond ialdehyde,MDA）含量,小鼠胸腺指数和脾脏指数的变化;核染色（Hoechst染色）法观察SPD对人神经母瘤细胞（SH-SY5Y）细胞凋亡的影响。结果SPD处理能够有效抑制小鼠肉瘤（S180）瘤体生长和离体肝肿瘤细胞生长（P〈0.05）;有效提高荷瘤小鼠胸腺指数和脾脏指数,提高SOD活性和降低MDA含量（P〈0.05）;促进神经母瘤细胞凋亡。结论SPD具有显著的抗肿瘤效应,其抑瘤机制可能与SPD促进免疫器官功能和提高抗氧化能力有关。

The Anti-tumor Effect and Mechanism of Soluble Polysaccharides from Dendrobium Candidum

Objective To study in vivo and in vitro tumor-inhibition of soluble polysaccharides from Dendrobium candidum（SPD） and to discuss the possible mechanism of its tumor-inhibition. Methods Tumor-inhibition of SPD was observed in mice inoculated with sarcoma S180 and in vitro human liver tumor cells SMMC27721.The superoxide dismutase（SOD） and malondialdehyde（MDA） in mice serum,and the change of index of thymus and spleen were detected and analyzed.The apoptosis of human neuroblastoma（SH2SY5Y） induced by SPD was observed and analyzed by Hoechst stain method. Results In vivo mice sarcoma S180 and in vitro human liver tumor cells SMMC27721 were inhibited significantly by SPD.The index of thymus and spleen and the activation of SOD was increased,but the level of MDA in mice serum was decreased by SPD.The apoptosis of SH-SY5Y was significantly promoted by SPD. Conclusion SPD has a remarked anti-tumor effect and its mechanism was probably related to promotion of immune organ function and oxidation-resistance.