The Changes Of P-glycoprotein Expression At The Hippocampus In The Diabetic Mice And The Effects Of Polygonatum Polysaccharide On Its Expression

Objective:To study the changes of P-glycoprotein expression at the hippocampus in the diabetic mice; To study the effects of polygonatum polysaccharide on the expression of P-gp at the hippocampus in the diabetic mice.Methods:Thirty male Kunming mice of8weeks(SPF) were randomized into normal control group(n=6) and model group(n=24) after7days adaptive feeding. The model mice were injected with45mg/kg streptozotocin into abdominal cavity for5days to induce the type1diabetes model(TIDM). The model mice with over11.1mmol·L of fasting serum glucose(FSG) after72hours were then randomly divided into the untreated TIDM group(n=8) and the TIDM group treated with polygonatum polysaccharide(n=8). The mice in the polygonatum polysaccharide group were administrated with25ml/kg.d polygonatum polysaccharide solution and given twice by gavages, those in the normal control group and model group were only fed with saline of the same volume for6weeks. During the period, observe the general situation and monitor the weight and FSG of the mice. The P-gp’s expression at the hippocampus was examined by Western Blot and at the same time the blood glycated hemoglobin(GHb) was measured.Results:The levels of FSG and GHb and the levels of the P-gp’s expression at the hippocampus were significantly increased in the untreated TIDM group than the normal control group. The levels of FSG and GHb were decreased and the levels of the P-gp’s expression at the hippocampus were significantly increased in the the TIDM group treated with polygonatum polysaccharide than the untreated TIDM group.Conclusions:1. P-gp expression increases at the hippocampus in the diabetic mice, which suggests diabetes mellitus may cause the transportation of intracranial drugs and endogenous physiological substances changes.2. polygonatum polysaccharide can significantly increase the expression of P-gp at the hippocampus of the diabetic mice, which prompts polygonatum polysaccharide is a P-gp inducer and may have protective effect on the impaired brain tissue of the diabetic mice, the specific mechanism needs to be further explored.