海带多糖对糖尿病小鼠胰岛素受体表达的影响

EFFECT OF SACCHARINA JAPONICA POLYSACCHARIDE ON THE EXPRESSION OF INSULIN RECEPTOR IN DIABETIC MICE

目的探讨海带多糖对实验性2型糖尿病小鼠胰岛素受体(InsR)表达的影响及其辅助降血糖作用。方法健康雄性昆明小鼠随机分为2组,对照组10只,普通饲料喂养;实验组高脂饲料喂养4周后,经腹腔注射四氧嘧啶制备2型糖尿病动物模型,随机分为治疗组和模型组,各10只,治疗组应用海带多糖灌胃干预治疗2周;模型组和对照组同步灌胃给予等量的生理盐水。自动血糖仪检测小鼠空腹血糖(FBG)水平,免疫组织化学和Western blot方法检测InsR蛋白表达,RT-PCR检测InsR mRNA丰度表达。结果经海带多糖治疗后,实验组动物血清FBG水平较模型组显著降低(F=4.0,q=3.2,P<0.05)。小鼠肝脏和胰腺组织中,实验组InsR着色均较模型组明显增强(F=329.04、52.81,q=25.1、6.0,P<0.05);InsR蛋白表达水平较模型组显著升高(F=180.92、137.20,q=4.6、14.4,P<0.05);而InsR mRNA丰度表达水平较模型组明显升高(F=116.35、402.37,q=12.6、14.4,P<0.05)。结论海带多糖可能通过提高肝脏和胰腺组织细胞InsR表达,减轻胰岛素抵抗,发挥降糖作用。

Objective To investigate the influence of Laminaria japonica polysaccharide （LJPS） on expression of insulin receptor （InsR） in experimental type 2 diabetes mellitus （TZDM） mice and its auxiliary hypoglycemic action. Methods Healthy Kunming male mice were randomly divided into two groups. Ten mice in the control group were given normal diet; 20 in the experi- mental group were fed with high fat diet for four weeks and then intraperitoneal alloxan was injected to create a model of T2DM. The diabetic model animals were evenly randomized to model group and treatment group. The mice in the treatment group were treated with intragastric administration of LJPS for two weeks, and those in the model and control groups were administered with equivalent amount of normal saline. The level of ~~asting blood glucose （FBG） was detected by automatic blood glucose device, the expression of InsR protein was determined by immunohistochemistry and Western blot, and the expression of InsR mRNA abu- ndance was detected by RT-PCR. Results After LJPS treatment, the FBG levels were much lower in the treatment group than that in the model group （F = 4.0, q = 3.2, P〈0.05）. A comparison between the treatment group and the model group indicated that in liver and pancreatic tissues, InsR coloring in the treatment group was enhanced （F =329.04,52.81 ; q= 25.1,6.0 ; P〈0.05）, the expression of InsR protein was higher （F = 180.92,137.20 ;q = 4.6,14.4;P〈0.05）, and the expression levels of InsR mRNA abu- ndance increased （F=116.35,40g.37;q=12.6,14.4;P〈0.05）. Conclusion The hypoglycemic activity of LJPS is probably by increasing the expression of InsR in liver and pancreatic tissue, and relieving insulin resistance.