人参皂苷是人参属植物的特征性成分，可分为中性皂苷和酸性皂苷;丙二酰基人参皂苷（MGR）是一种酸性皂苷，其含量在人参中约占总皂苷的50%，然而这类皂苷的化学成分研究报道较少，药理活性几乎处于空白。这严重的影响了人参属植物的临床应用和国际推广。我们在前期的工作中，首次发现了MGR具有显著的降糖活性，且明显强于中性皂苷，进一步发现其降糖作用与改善胰岛素抵抗(IR)有关。.为此本项目拟通过建立MGR快速的识别和分离方法，对人参属植物人参、西洋参和三七中MGR进行系统的分离，评价和研究其改善IR的生物活性和构效关系。同时采用同位素标记相对和绝对定量蛋白质组学技术，对2型糖尿病IR靶器官进行高通量的“全组”蛋白鉴定和定量分析，筛选出差异蛋白；并结合生物信息学手段对其生物学功能进行分析，阐明作用机制。本项目将使我们对人参属植物抗糖尿病的物质基础有一个全新的认识，为创制新型抗糖尿病药物提供活性先导化合物。

Ginsenosides are the characteristic and major constituents of the Panax genus species,including neutral ginsenosides(NGR)and acidic ginsenosides (AGR).Malonyl ginsenosides (MGR) are also called acidic ginsenosides. Previous studies have shown that the content of malonyl ginsenosides represents up to 50% of the total content in ginsenosides of Panax ginseng root. However, MGR are more polar and water-soluble than NGR, and MGR are more difficult to isolate and characterize than NGR.Therefore,very little work has been carried out on the chemical constituents,and the pharmacological effects of MGR have not been explored so far.These will cause negative effect on the clinical application and international development of Panax species. In the previous investigation, we reported the significant hypoglycemic effects of MGR extracted from panax ginseng for the first time, and MGR exhibited significantly more potent antihyperglycemic activity than NGR. Further experiments revealed that the hypoglycemic effects of MGR were associated with amelioration of insulin resistance (IR).. On the basis of our previous research, this project will establish a rapid method to systematically isolate, prepare, and identity MGR from Panax ginseng,Panax quinquefolius,and Panax notoginseng. Studies will also be carried out on the biological activites of MGR on glucose metabolism with insulin-resistance cells, as well as their structure-activity relationship and qulity evaluation. Further, we use quantitative proteomic approach with isobaric labeling (iTRAQ) to examine the differential proteins among pathological organ and tissue in type 2 diabetes mice treated with MGR compared to untreated diabetes mice. Mass spectrometry is applied to identify the differentially expressed proteins. Meanwhile, we analyze their biological function with proteomics bioinformatics analysis. Our study for the first time couple iTRAQ with TOF/MS on IR of type 2 diabetes mice to discover new information about the malonyl ginsenosides mechanism of action and drug target. These results of the project would provide not only a renewed knowledge on the material basis of Panax species but also a theoretical basis for anti-diabetic lead compounds of ginseng saponins.