Studies On The Hypoglycemic Effect Of Polysaccharide From Prinsepia Utilis Royle In Diabetic Mice

Objectives: To investigate the hypoglycemic effects of polysaccharide from prinsepia utilis royle in diabetic mice which induced by the alloxan and its mechanism of action.Methods: Alloxan(ALX,300mg/kg) was administered intraperitoneally to establish diabetic models in mice, after the success of modeling, experimental animals were divided into the model group(physiological saline), the polysaccharide from prinsepia utilis royle group(PPR,300 mg/kg), acarbose group(AR,20 mg/kg), set up a normal control group(physiological saline). After the administration for two and four weeks,the level of blood glucose(GLU)and the contents of triglyeride (TG),very low density lipoprotein cholesterol(VLDL-C),alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen(BUN),total cholesterol(TC), the body weight after fasting 12 hours were detected respectively. The polysaccharide from prinsepia utilis royle group was compared with the model group and acarbose group were to compare. The same time each group randomly selected four mice were sacrificed, heart, liver, lung and kidney were taken out, and then fixed with the 4% paraformaldehyde, paraffin sections were made,The heart were stained only with Hematoxylin and Eosin (HE).HE staining was carried on the liver, and liver index of determination. HE staining and Gomori silver staining were carried on the lung. kidney were stained with HE, Periodic Acid Schiff(PAS) and Gomori silver staining reseparately, the kidney weight was measured, 1mm~3 of renal cortex fixed with 2.5% glutaraldehyde in four centi-degree after four weeks, ultrathin section was made,and then the ultrastructure of each group was observed under electron microscope.Results:1 The effects of polysaccharide from prinsepia utilis royle on glycemia and serum lipoprotein levels in diabetic mice induced by alloxan as follow:After two weeks, the polysaccharide from prinsepia utilis royle group and acarbose group compared with the model group, the level of blood glucose and alanine aminotransferase decreased significantly(P<0.05) , but had no significant effect on the level of triglyeride, low density lipoprotein cholesterol, aspartate amino transferase, urea nitrogen and total cholesterol. And the body weight increased significantly (P<0.05).Compared to the acarbose group,all serum biochemistry of the polysaccharide from prinsepia utilis royle group had no differences(P>0.05).After four weeks, compared with the model group, the polysaccharide from prinsepia utilis royle group and acarbose group could obviously decrease the level of blood glucose,triglyeride, low density lipoprotein cholesterol,aspartate amino transferase,blood urea nitrogen (P<0.05), as well as the level of alanine amino transferase decreased significantly (P<0.01),the body weight obviously increased(P<0.05), it had no significant effect on the level oftotal cholesterol. The level of low density lipoprotein cholesterol and alanine aminotransferase of the polysaccharide from prinsepia utilis royle group reduced significantly(P<0.05),it had no differences on the level of blood glucose, triglyeride, aspartate amino transferase, blood urea nitrogen,total cholesterol,the body weight increased,but had no differences(P>0.05).2 The protective effects of polysaccharide from prinsepia utilis royle on the heart tissue in diabetic mice as follow:In the model mice, longitudinal striation and transverse striation of cardiac muscle fibers were unclear, myocardial cells developed granular degeneration and fatty degeneration. Some cardiac muscle fibers mixed together with each other. Eosinophils changed cardiac muscle fibers were distributed multifocally, and there were myocardial cell degeneration and necrosis, longitudinal striation and transverse striation disappeared, there were fibroblast hyperplastic areas in interstitium and then myocardial fibrosis formed cicatricle. After treated with polysaccharide from prinsepia utilis royle, longitudinal and transverse striation of cardiac muscle fibers become clear, lined up in order, eosinophils changed heart muscle fiber reduced, that little fibrocyte proliferation.3 The protective effects of the polysaccharide from prinsepia utilis royle on the liver in diabetic mice as follow:The polysaccharide from prinsepia utilis royle group and acarbose group compared with the model group, were remarkably reduced the liver index of those(P<0.05).Compared to acarbose group, the polysaccharide from prinsepia utilis royle group was no differences(P>0.05).The light microscope, HE staining the mice that liver cell cords of the model mice was disordered, liver sinusoid become widened,fibrocyte between liver cells cords were proliferated. There were fatty degeneration and focal necrosis in liver cells,a large number of inflammatory cells developed infiltration in necrotic areas of those and around the central veins. After treated with polysaccharide from prinsepia utilis royle group, structure of liver cell cord become clear,liver sinusoid almost recovered. The number ofproliferated fibrocyte reduced, there were slightly granular degeneration in hepatic cells.4 The protective effects of polysaccharide from prinsepia utilis royle on the lung tissue in diabetic mice as follow:Under light microscope, HE staining the model group mices that alveolar septum was widened,there were inflammatory cell infiltration in around the bronchus and alveolar septum, pulmonary capillary based membrane thickened,hemosiderin happened deposition obviously. Gomori silver staining that the content of reticular fibers and collagenous fibers increased in around bronchus, alveolar septum and the small vessels. After treated with polysaccharid from prinsepia utilis royle, there was a slight congestion in alveolar septum and alveolar space, inflammatory cell infiltration relieved in the surrounding of bronchus, little reticular fibers and collagenous fibers was in bronchus, alveolar septum and in the surrounding of small vessels.5 The protective effects of polysaccharide from prinsepia utilis royle on the nephridial tissue in diabetic mice as follow:In model group, kidney index of mice markedly increased. Under light microscopy, glomerular basement membrane thickened and extracellular matrix increased, glucogen material obviously deposited, the content of reticular fibers and collagenous fibers increased. Tubular epithelial cell happened vacuolar degeneration, many protein cast was in nephric tubule lumens, inflammatory cells infiltration was in renal interstitium. GBM thickened irregularity,foot process mixed together, chromatin margination appeared in cell nucleus, the mitochondria of tubular epithelial cells happened swelling and vacuolar degeneration, crista mitochondriales fell off, decreased or disappeared. After treated with the polysaccharide from prinsepia utilis royle, compared with the model group,the kidney index significantly decreased(P<0.05).compared with acarbose group, it had no differences(P>0.05).GBMdid not thick obviously,extracellular matrix,glucogen material and number of fibers decreased, protein cast and inflammatory cells infiltration almost disappeared. Structure of renal tubule almost become to normal, cytochondriome swelled and degenerated slightly.Conclusions: Polysaccharide from prinsepia utilis royle can effectively reduce the levels of blood glucose in diabetes mice, regulate the blood lipid disorder, improve shape and organization of the kidney, liver, lung and heart, change the unusual. It has the certain protective function to the tissues and organs of diabetes mice.