The Study Of The Hypoglycemic Mechanism Of Gynostemma Pentaphyllum Based On Network Pharmacology

Background:Gynostemma pentaphyllum（（Thunb.）Makino,GP）is a widely used traditional Chinese medicine.Modern pharmacological studies have found it has a variety of pharmacological activities,such as lowering blood sugar and blood lipid,anti-tumor,immune regulation,liver and cardiovascular protection.In recent years,studies have found that the active components of GP have good hypoglycemic effects.However,the mechanism of its action in treating diabetes remains unclearObjective:The objective of this study is to reveal the molecular mechanism of GP in the treatment of diabetes.Methods:Firstly,the main active compounds and targets of GP were screened by TCMSP,HPLC-MS/MS,Swiss Target Prediction database and literature.In addition,Cystoscope software was used to construct and analyze the"drug-active ingredients-targets"network.All diabetes related targets were obtained from Gene Cards database.The PPI network and active components/targets networks were constructed by String database and Cytoscape software to identify the potential drug targets.The functions and pathways of targets were analyzed through DAVID database.Finally,DS was used for molecular docking to evaluate the binding ability between the compounds and the main targets.To support our prediction,we explore the treatment of diabetes effect and mechanism of GP and representative component（Gypenoside XVII）by in vitro experiments.Furthermore,we evaluated the bioactive constituents of GP and molecular mechanism by Western blot analysis.Results:A total of 32 active ingredients a and 54 common targets were obtained and used to construct the networks.The PPI protein interaction network map showed that the targets closely related to diabetes included Akt1,PIK3CA,STAT3,VEGFA and EGFR.GO analysis showed that GP active substances were mainly involved in multiple biological processes of insulin.The KEGG enrichment analyses revealed that the common targets were involved in multiple signaling pathways,including the insulin pathway,FOXO pathway,VEGF pathway,TNF pathway and PI3K/Akt pathway.which is closely related to diabetes.The molecular docking results showed that most of components associated with core targets could bind spontaneously.In addition,Gypenoside XVII is the main component of GP.Therefore,Gypenoside XVII was selected as the representative substance for subsequent studies.Verification through in vitro experiments found that GP extract and Gypenoside XVII can significantly increase the absorption and consumption of glucose in insulin resistance（IR）Hep G2 cells,and reduce the lipid accumulation in IR Hep G2 cells in a dose dependent manner.In addition,we confirmed that GP extract and Gypenoside XVII can significantly decrease the protein expression levels of p-IRS1,Akt,GSK-3β,p-GS,FOXO1,PEPCK and G6Pase,and increase the protein expression level of IRS1,PI3K,p-Akt,p-GSK-3β,GS and p-FOXO1.Which suggests that GP extract and Gypenoside XVII can treat T₂DM by regulating the PI3K/Akt signaling pathway.Conclusions:Gypenoside XVII and GP extract promote glycogen synthesis by activating IRS1/PI3K/Akt/GSK-3βsignaling pathway,inhibit Gluconeogenesis by activating IRS1/PI3K/Akt/FOXO1 signaling pathway to inhibit G6Pace and PEPCK expression,and thus achieve hypoglycemic effect.