Study On Hypoglycemic Effect Of Huangjing Compound Extract

Diabetes mellitus(DM) is a endocrine metabolic disease. With the economic development and the improvement of people's living standard, diabetes prevalence rate keeps rising every year becoming a worldwide and frequently occurring common disease. Its etiology is complex and the specific mechanism is unknown. The pathogenesis of type I diabetes mellitus is related to the allele of human leukocyte antigen(HLA) and the major histocompatibility complex(MHC) ?. The incidence of the disease is about 5-10%. Type II diabetes due to insulin secretion defects can lead to ? cell function impaired and oxidative stress, the inhibitory feedback deficiency of pathological characteristics and plasma pancreatic high blood glucose levels of the hormone, long-term exposure to free fatty acids, lipid toxicity and high blood sugar.At present, many Chinese traditional medicine and its compound used for the treatment of diabetes only can treat just right for the illness, can not permanetly cure, less effective and with side effects. So it is essential to develop new diabetes drugs. The compound sealwort extract used in the experiment, was composed of Polygonatum sibiricum, Lycium chinense, Polygonatum odoratum(Mill.)Druce, Zizyphus Jujuba Mill, according to a certain proportion of combination, and then extract the concentration. These four medicinal herbals are all used as food and drug, and a large number of literatures prove that it has the prevention and treatment of diabetes and its complications. As most papers prove that the compound sealwort extract of each component is related to the oxidative stress, a-glucosidase inhibitory activity, cyclic adenosine monophosphate(cAMP) and guanosine monophosphate (CGMP) and other related mechanism. Therefore, the study of compound sealwort extract on body oxidative stress indicators, a-glucosidase activity inhibition and liver, plasma of cAMP, cGMP and cAMP/cGMP effects. Firstly, this thesis studies the selection and optimization of conditions of alloxan induced diabetic model, then the improvement of alloxan pyrimidine high glucose in rat model of glycemic index by the extract. At last, discuss the hypoglycemic mechanism of the compound sealwort extract.The main research contents are as follows:1. Screen the alloxan induced diabetic model and explore the hypoglycemic effect of compound sealwort extract. According to the administration route and doses, the Alloxan (Alx) modeling method is divided into three groups:i.v.60mg/kg Alx; i.p. 200mg/kg Alx, continuous 2d i.p.150mg/kg Alx, the glucose valuing 16.7-30mmol/L after modeling is successful modeling. Record the rate of death and mortality of mice. And diabetic rats according to their blood glucose values were randomly divided into five groups and positive group irrigation gastric 10mg/kg of glimepiride, low, middle and high dose group respectively by gavage 100,300,900mg/kg Polygonatum compound extract. The model group and normal group were given normal saline. FPG, HbAlc,Insulin and OGTT were measured once per 2w, and the calculation of AUC.2. Study on mechanism of hypoglycemic effect of compound sealwort extract(1) Oxidative stress indicators:the mice were killed on the 30th day. And then body weight, spleen, liver index and serum, SOD, MDA, GSH-Px levels in serum, SOD, MDA, GSH-Px, CAT, HK, PK levels in liver were measured.(2) Other indexes:effect of compound eealwort extract on a-activity inhibitory and cAMP, cGMP and cAMP/cGMP in plasma and liver of mice in each group. Experimental results:1.i.p.150mg/kg ALX 2d method was used to establish the DM model continuously, which has a high rate of model formation and the deaths is fewer. It is a good method to modeling alloxan induced high glucose mice. The three groups of compound sealwort extract has a better reduction of FPG and AUC than the model group, and the HbAlc value tends to normal level.2.The analysis of the indicators of oxidative stress:the compound sealwort extract can significantly reduce the oxidative stress damage of organism. The result shows that the concentration of the extract is 900mg/kg has a better antioxidant effects.3.The inhibition rates of the ?-activity of 100,300 and 900mg/kg in compound sealwort extract were 16.75%,27.89% and 47.68%, respectively. The cAMP and cAMP/cGMP of plasma and liver of the three groups were significantly increased, but the change of cGMP was little.Conclusion:The compound sealwort extract has the function of reducing blood sugar in alloxan induced high-sugar model mice. Its specific hypoglycemic mechanism may be related to oxidative stress, ?-glucosidase enzyme and the second messenger cAMP, cGMP, etc.