琼脂寡糖对糖尿病小鼠血糖和氧化-抗氧化态的效应

目的:探讨以琼二糖为主的琼脂寡糖对糖尿病小鼠的血糖及其氧化-抗氧化效应的影响。方法:利用α-葡萄糖苷酶活性的检测,研究琼二糖的降血糖机制。通过四氧嘧啶建立小鼠糖尿病模型,给药14d后,检测小鼠血糖及心、肺、肝、脑的MDA、GSH、GSH-Px、SOD水平。结果:在200～400mg/kg的剂量范围内,琼脂寡糖(含87.68%琼二糖)可明显降低糖尿病小鼠的血糖含量及各氧化指标,血糖值低于两种阳性对照组(P<0.01)。各组织的MDA水平明显下降(P<0.01),GSH,GSH-Px和SOD活性也得到较明显提高。结论:琼脂寡糖可能是通过抑制α-葡萄糖苷酶和抗氧化作用降低糖尿病小鼠的血糖水平,并可提高某些组织的抗氧化能力。

EFFECTS OF AGAR-OLIGOSACCHARIDES ON BLOOD GLUCOSE LEVEL AND OXIDATION-ANTIOXIDATION STATUS OF DIABETIC MICE

Objective:To evaluate the effect of agar-oliogsaccharides (mainly containing agarobiose) on blood glucose level and oxidation-antioxidation status in alloxan-induced diabetic mice. Method: The inhibitory activity of agarobiose on α-glucosidase was investigated. Alloxan was used to establish non-obese diabetic (NOD) mice model. After 14 d administration of agarobiose, blood glucose, MDA, SOD, GSH and GSH-Px levels were determined. Results:Agarobiose showed inhibitory activity on α-glucosidase with IC50=1.39 mg/ml, Ki=0.52 mg/ml. In a certain concentration (200-400 mg/kg bw), agaro-oligosaccha- rides reduced the blood glucose level remarkably, and the oxidative indices were also improved in heart, liver, lung and brain. The blood glucose level (P<0.01) was lower than that injected with ascorbic acid or acarbose, and MDA level was also reduced significantly (P<0.01). Furthermore, GSH, GSH-Px and SOD activities we re improved remarkably. Conclusion: Agaro-oligosaccharides could achieve their hypoglyce- mic effect through inhibition of α-glucosidase, reduction of oxidative stress and improvement of antioxidant ability.