ABSTRACT
ObjectiveTo explore the effects of Gegen Qinliantang（GGQL） on the proliferation and apoptosis of intestinal epithelial cells as well as on the expression of cyclic adenosine monophosphate （cAMP）， G protein-coupled receptor 119 （GPR119）， and glucagon-like peptide-1 （GLP-1）， so as to explore its potential hypoglycemic mechanism. MethodTwenty-five Wistar rats were gavaged with GGQL at the dose of 23 g·kg-1 crude drug， twice a day， which meant that 6 mL was administered into each rat per day for preparing the GGQL-containing serum. After seven consecutive times of administration， the intestinal epithelial L （NCI-H716） cells were cultured with different concentrations （1%， 2.5%， 5%， 7.5%， and 10%） of GGQL. The cell proliferation was evaluated using cell counting kit-8 （CCK-8） and the apoptosis by flow cytometry. The GLP-1 and cAMP contents in cell supernatant were determined by enzyme-linked immunosorbent assay （ELISA）. The mRNA and protein GLP-1 and GPR119 levels were assayed by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot， respectively. ResultCompared with the control group， GGQL significantly reduced the proliferation of NCI-H716 cells（P<0.05）. As the GGQL concentration increased， its inhibitory effect became more obvious. GGQL at each concentration significantly promoted the apoptosis of NCI-H716 cells （P<0.05）. Compared with the control group， GGQL significantly up-regulated the expression of cAMP， GLP-1， and GPR119 （P<0.05）. The results showed that the effect of GGQL was positively correlated with its concentration， and 10% GGQL exhibited the best effect. ConclusionGGQL effectively inhibits the proliferation of NCI-H716 cells and promotes their apoptosis， and it may promote the secretion of GLP-1 by up-regulating the expression of cAMP and GPR119.
ABSTRACT
The categorical structure-activity relationship (cat-SAR) expert system has been successfully used in the analysis of chemical compounds that cause toxicity. Herein we describe the use of this fragment-based approach to model ligands for the G protein-coupled receptor 119 (GPR119). Using compounds that are known GPR119 agonists and compounds that we have confirmed experimentally that are not GPR119 agonists, four distinct cat-SAR models were developed. Using a leave-one-out validation routine, the best GPR119 model had an overall concordance of 99%, a sensitivity of 99%, and a specificity of 100%. Our findings from the in-depth fragment analysis of several known GPR119 agonists were consistent with previously reported GPR119 structure-activity relationship (SAR) analyses. Overall, while our results indicate that we have developed a highly predictive cat-SAR model that can be potentially used to rapidly screen for prospective GPR119 ligands, the applicability domain must be taken into consideration. Moreover, our study demonstrates for the first time that the cat-SAR expert system can be used to model G protein-coupled receptor ligands, many of which are important therapeutic agents.