| Object: To investigate the components and hypoglycemic effect of alkaline extracts from Fagopyrum tararicum and explore the hypoglycemic mechanism,which providing the basis for clinical application in the future.Method: 1 The HPLC-MS analysis of alkaline extracts from Fagopyrum tararicum The 50 kg Fagopyrum tararicum seeds of Fagopyrum tararicum were extracted,collected,concentrated,filtered and separated by anioncation exchange resin.Then the main components of alkaline extracts from Fagopyrum tararicum were analyzed by HPLC-MS.2 Hypoglycemic effect of alkaline extracts from Fagopyrum tararicum on the Type 2 diabetic rats 80 Healthy SD rats(male,SPF)were fed adaptively for 1 week then randomly divided into 2 groups,8 for the normal group and 72 for the high-fat high-sucrose group.The normal group was fed with normal diet.The high-fat high-sucrose group was fed with high-fat high-sucrose diet for 4 weeks to induce type 2 diabetic rat model by intraperitoneal injection of 1% streptozocin(35 mg/kg),the blood glucose was measured with the tail cut method after intraperitoneal injection for 7 days and those fasting blood glucose > = 11.1 mmol/L were chosen as successful models.Then 40 of these rats were randomly divided into 5 groups,namely model group,low dosage of Fagopyrum tararicum extracts group(43 mg/kg),high dosage of Fagopyrum tararicum extracts group(86 mg/kg),metformin group(140 mg/kg)and acarbose group(32 mg/kg),each with 8.Groups of rats were gavaged with medicine twice a day for 6 weeks,the body weight,food intake,water intake of all the rats were measured and recorded every week.Blood glucose and urine output of the rats at 1,2,4 and 6 week were measured after gavege administration.The food but not water was forbidden for 12 h before the last administration.Blood was collected from the common carotid artery and serum was kept for inspection;The kidney,heart,pancreas and liver tissue were separated by rapid blunt dissection after blood was taken.The weight of these tissue were measured and the viscera index(viscera index =viscera weight/body weight)were calculated after dried by filter paper.Part of the tissues were fixed in 4% paraformaldehyde for HE staining then the morphological changes were observed under optical microscope the others were reserved at-80?.3 hypoglycemic mechanism on Type 2 diabetic rats of alkaline extracts from Fagopyrum tararicum The ?-glycosidase activity of acarbose and alkaline extracts from Fagopyrum tararicum with concerntration of 62.5 mg/L respectively,125 mg/L,250 mg/L,500 mg/L,1000 mg/L was measured by the 4-nitro-phenol-alpha-D-pyran glycosidase(PNPG)method.The m RNA expression of AMPK,PI3 K,Akt in liver tissue was detected by real time quantitative PCR method after the extraction of total RNA from liver tissue.The relative expression of PI3 K,Akt in liver tissue was determined by western blot as well.Results: 1 The experimental results showed that 7 kinds of polypeptides and a hydroxyl alkaloid were detected and identificated in the alkaline extracts from Fagopyrum tararicum.2 The experimental results showed that the blood glucose,food intake,water intake,serum insulin and glycated hemoglobin level in type 2 diabetic rats were reduced significantly in high and low dosage of Fagopyrum tararicum extracts groups after six weeks of treatment comparing with model group.3 The effects on rat kidney index,cardiac index,the pancreas and liver index: After statistical analysis,no significant differences of the rat kidney index,heart index and liver index were found in all medication administration groups and model group.Pancreatic index of the model rats was higher than the normal rats.4 Pathological examination: it showed that there were no significant lesions of heart and kidney in each group.The islet size of the model rats were less than the normal rats and the fatty liver was formed as well.The lesion of diabetes rats was improved after the treatment.5 The median inhibition rate of ?-glycosidase by alkaline extracts from Fagopyrum tararicum was 116.468±1.065 mg/L.Meanwhile,the gene expression of PI3 K and Akt in the livers of rats increased significantly,the gene expression of AMPK increased but the difference was not statistically significant.The protein expression of PI3 K,Akt,p-PI3 K and p-Akt in the livers of rats increased obviously.Conclusion:1 The alkaline extracts from Fagopyrum tararicum can reduce the blood glucose of type 2 diabetic rats,improve the function of pancereatic islets and increase insulin sensitivity.2 The alkaline extracts from Fagopyrum tararicum can improve the condition of type 2 diabetic rats by the inhibition of ?-glycosidase and the regulation of PI3K-AKT signaling pathway to up-regulate the PI3 K ?Akt gene and the expression of protein. |
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