凹顶藻萜类化合物抑瘤作用及其机制研究

目的:观察凹顶藻萜类化合物(Laurencia terpenoid extract,LET)的抑瘤活性、免疫调节作用及对S180细胞凋亡的影响,初步探讨其抗癌作用机制。方法:采用Horn法检测其安全性(LD50)。建立S180荷瘤鼠动物模型,采用LET低、中、高剂量(25、50、100mg/kgbw)灌胃,空白对照组以大豆色拉油灌胃,每日一次,连续10d。测定抑瘤率;计算胸腺指数、脾指数;用MTT法测定脾淋巴细胞增殖活性;流式细胞术检测LET诱导的S180细胞凋亡和对细胞周期的影响。结果:LET的LD50>3160mg/kgbw属低毒。LET低、中、高三个剂量组的平均瘤重低于空白对照组(P<0.05),高剂量组的抑瘤率达39.1%。与空白对照组比较,LET低剂量组的胸腺指数上升、高剂量组的脾指数上升(P<0.05),LET低、中剂量组的脾淋巴细胞增殖率升高(P<0.05),高剂量组的脾淋巴细胞增殖率明显升高(P<0.01)。LET中剂量组S180细胞凋亡率高于空白对照组(P<0.05)。结论:LET使用安全,可明显抑制小鼠S180移植瘤的生长,其作用机制可能与其可提高机体的免疫功能,诱导S180细胞凋亡和阻断该细胞于G0/G1生长期有关。

THE ANTICANCER ACTIVITIES AND MECHANISM OF LAURENCIA TERPENOIDS EXTRACT

Objective:To investigate the effect of Laurencia terpenoid extract (LET) on tumor inhibition,immune modulation and apoptosis of Sarcoma 180 cell. Method:The LD50 of LET was estimated by Horn assay. The models of S180-bearing mice were established and divided into 4 groups which were given LET 0 (control group), 25 (low-dose group), 50 (mid-dose group), 100 (high-dose group) mg/kg bw respectively for 10 d. Tumor inhibition rates were detected in treatment groups and control group respectively. To weigh exactly the thymus and spleen to calculate their indices. The proliferation effect of LET on spleen lymphocyte was evaluated by MTT assay. The apoptosis of tumor cell was assayed by flow cytometry. Results:The LD50 was more than 3 160 mg/kg bw. LET had low toxicity. The average tumor weights of the supplemented groups were all less than the control group(P<0.05). The tumor inhibition rate of the high-dose group was 39.1%. Mid-dose LET obviously increased the level of thymus index. High-dose LET obviously increased the level of spleen index. LET increased the multiplication of spleen lymph cells. Apoptosis of S180 of supplemented groups was significantly higher than the control group (P<0.05). Conclusion:LET is safe and can strengthen the immune system, and induce apoptosis of S180 cells,increase of cells in G0/G1 phase and decrease in S phase.