High Throughput Screening Of Agonist For GLP-1 Receptor From Chinese Traditional Medicine Library

The incidence of diabetes mellitus is increasing year after year. Now diabetes mellitus is the third disease following cardiopathy and cancer. Diabetes mellitus include type 1 and type 2. The percent of type 2 diabetes mellitus is over 90% in diabetes mellitus. Type 2 diabetes mellitus is aroused by insulin resist or insulin secretion limitation. High blood sugar is the primary clinical symptom of tape 2 diabetes. At present, there is much progreses in drug therapy of type 2 diabetes mellitus. But many drugs will arouse side-effect. So it is the first task for screening a efficacious drug. High throughput screening is a new technology for drug screening, it combine automatism operating system with sensitive examine system. It can evaluate the compound through drug screening model based-on cell or molecule. Speediness, efficacious, big scale, low wastage are it's excellencies for drug screening. With the development of life sciences, more and more drug targets relation to type 2 diabetes mellitus are discovered , which establish stability basic for high throughput screening type 2 diabetes mellitus drugs.Glucagon-Like Petide-1 is a kind of hormone deriving from Proglucagon, it can arouse insulin secretion after taking orally or injecting glucose. So GLP-1 went by the name of intestines promote insulin, it is released by intestines and paunch in the course of digesting. GLP-1 can explode its receptor. Through binding GLP-1 receptor , it can arouse insulin secretion, increase sensitivity of insulin, restrain glucagon secretion and slower the velocity of stomachic emptying. More recent studies showed that GLP-1 is effective for both type 1 and type 2 diabetes mellitus. Treatment of type 2 diabetes patients with GLP-1 does not lead to hypoglycemia. Therefore, high throughput screening of agonist against for GLP-1 receptor is a new way in the drug curing type 2 diabetes mellitus.To establish a model for high throughput screening the agonist of GLP-1 receptor, the GLP-1 receptor gene was inserted into pCDNA3.1 carrier to establish GLP-1 R plasmid. Then GLP-IR plasmid and reprotor gene plasmid(3×CRE/3×MRE/SRE-LUC/ pGL3) were cotransfected HEK293 cell line, the ratio of GLP-1R plasmid and reprotor gene plasmid was 1:5. In order to optimize the screening condition, some factors were examined by stimulating the GLP-1R cell with GLP-1, including cell number in each cell, incubation time, dosage of Bright-GloTM and concentration of DMSO.When a compound binds to GLP-1 receptor, it will activate GLP-1 receptor andthe signal pathway to change the expression of the second messagers in the cell. Responsive elements respond to this change and cause the expression of reporter gene. The bioactivity of the compound can be evaluated after the expression of the reporter gene was measured.In the experiment, 500 Chinese traditional medicines were studied. Through extracting, a Chinese traditional medicine extract library was established, using the drug screening model, we had screening the library to found the agonist of GLP-1 receptor. As a result, 5 samples showed high bioactivity.