泰山玉竹多糖对小鼠糖尿病的治疗作用及细胞免疫机制研究

Effect and Cellular Immunological Mechanism on Mice of Diabetes with Extraction of Polysaccharide from Taishan Polygonatum odoratum

摘要: 目的：研究泰山玉竹提取物玉竹多糖(EA-PAOA)对I型糖尿病小鼠的降血糖作用及可能的细胞免疫学机制。方法：采用常规的链脲佐菌素(STZ)多次注射诱导法制备I型糖尿病小鼠模型，试验组分低、中、高三个剂量灌胃等体积的EA-PAOA，对照组灌胃等体积的生理盐水。于用药后1~4周每周检测各组小鼠血糖和胰岛素水平；通过流式细胞仪检测外周血CD4⁺T细胞和CD8⁺T细胞比例，采用酶联免疫吸附实验(ELISA)检测血清Th1型细胞因子γ干扰素(IFN-γ)和Th2型细胞因子白细胞介素4 (IL-4)浓度。最后进行数据的统计学分析。结果：与模型组相比，实验组空腹血糖水平显著降低(P < 0.05~0.01)；胰岛素水平则显著升高(P < 0.01)；外周血CD4⁺T细胞比例显著降低而CD8⁺T细胞比例显著降低(P < 0.01)，CD4⁺/CD8⁺比例显著降低(P < 0.01)。血清中Th1型细胞因子IFN-γ显著降低(P < 0.05~0.01)，而Th2型细胞因子IL-4显著升高(P < 0.05~0.01)。结论：泰山玉竹多糖治疗能明显降低1型糖尿病小鼠血糖，其降糖作用可能通过调节糖尿病小鼠T细胞亚群及Th1型和Th2型细胞因子水平而发挥的。

Abstract: Objective: To study the therapeutic effects of extraction from Polygonatum odoratum (EA-PAOA) from Taishan on type 1 diabetes and the possible immunological mechanism. Methods: Diabetic mouse models were established by repeated injection of small dosage of STZ. Mice were divided into 3 different groups according to different concentrations of EA-PAOA which were administrated by intragastric. The control group was administrated the same volume saline by intragastric. Changes of blood glucose, insulin were monitored from 1 to 4 weeks after administration. Changes of levels of serum interferon γ (IFN-γ) and interleukin-4(IL-4) in diabetic mouse were tested with enzyme- linked immunosorbent assay (ELISA) after administration. Finally, data were analyzed by statistic method. Results: Levels of blood glucose were significantly lower after administration in all extrac-tion groups than that in the model group (P < 0.05 - 0.01). Levels of insulin were significantly higher after administration in all extraction groups than that in the model group (P < 0.01). In the periph-eral blood, CD4⁺ T cells were significantly decreased, whereas CD8⁺ T cells were significantly in-creased (P < 0.01), and the ratio of CD4⁺/CD8⁺ was significantly decreased (P < 0.05 - 0.01). Levels of type 1 cytokine IFN-γ were lower in each extraction groups than that in the model group, whereas levels of type 2 cytokine IL-4 were significantly higher in each extraction groups than that in the model group (P < 0.05 - 0.01). Conclusion: EA-PAOA can markedly decrease the blood glucose of the in mice with diabetes. The mechanisms were probably related to regulating of T cell subsets.