title: Characterization of Secondary Metabolites from Purple Ipomoea batatas Leaves and Their Effects on Glucose Uptake.
abstract: Ipomoea batatas has long been used in folk medicine for the treatment of hyperglycemia or as a food additive for the prevention of type 2 diabetes. However, neither the plant extract nor its active components have been evaluated systematically. In this work four crude extracts, including n-hexane- (IBH), 95% MeOH- (IBM), n-BuOH- (IBB), and H₂O-soluble (IBW) fractions, were prepared by fractionation of a methanolic extract of purple I. batatas leaves. Twenty-four pure compounds 1-24 were then isolated by various chromatographic techniques and their structures identified from NMR and MS data. Glucose uptake assays in differentiated 3T3-L1 adipocytes and rat primary hepatocytes, as well as western blot analysis, were carried out to evaluate the antidiabetic activity of this species. The IBH crude fraction, with methyl decanoate (22) as a major and active compound, showed the greatest effect on glucose uptake, most likely via activation of Glut4 and regulation of the PI3K/AKT pathway. Quercetin 3-O-β-d-sophoroside (1), quercetin (3), benzyl β-d-glucoside (10), 4-hydroxy-3-methoxybenzaldehyde (12), and methyl decanoate (22) could be important components contributing to the antidiabetic effects. We conclude that purple I. batatas leaves have potential as an antidiabetic plant source and the active constituents 1, 3, 10, 12, and 22 are promising lead candidates for future investigation.
authors.affiliation: Department of Cosmeceutics, China Medical University, Taichung 40402, Taiwan. chlilee@mail.cmu.edu.tw.|Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung 40447, Taiwan. chlilee@mail.cmu.edu.tw.
authors.forename: Chia-Lin
authors.initials: CL
authors.lastname: Lee
authors.affiliation: Department of Biological Science and Technology, China Medical University, Taichung 40402, Taiwan. sllee@mail.cmu.edu.tw.
authors.forename: Shou-Lun
authors.initials: SL
authors.lastname: Lee
authors.affiliation: Graduate Institute of Integrated Medicine, China Medical University, Taichung 40402, Taiwan. cjchen@mail.cmu.edu.tw.|Proteomics Core Laboratory, Department of Medical Research, China Medical University Hospital, Taichung 40447, Taiwan. cjchen@mail.cmu.edu.tw.
authors.forename: Chao-Jung
authors.initials: CJ
authors.lastname: Chen
authors.affiliation: Department of Cosmeceutics, China Medical University, Taichung 40402, Taiwan. c0706@mail.cmu.edu.tw.
authors.forename: Hsin-Chun
authors.initials: HC
authors.lastname: Chen
authors.affiliation: Department of Biological Science and Technology, China Medical University, Taichung 40402, Taiwan. mckao@mail.cmu.edu.tw.|Department of Biochemistry, National Defense Medical Center, Taipei 11466, Taiwan. mckao@mail.cmu.edu.tw.
authors.forename: Ming-Ching
authors.initials: MC
authors.lastname: Kao
authors.affiliation: Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung 40447, Taiwan. bc00025@yahoo.com.tw.
authors.forename: Chuan-Hao
authors.initials: CH
authors.lastname: Liu
authors.affiliation: Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung 40447, Taiwan. day_7749@hotmail.com.
authors.forename: Jau-Yang
authors.initials: JY
authors.lastname: Chen
authors.affiliation: Department of Biological Science and Technology, China Medical University, Taichung 40402, Taiwan. wawagay@hotmail.com.
authors.forename: Yen-Ting
authors.initials: YT
authors.lastname: Lai
authors.affiliation: Chinese Medicine Research and Development Center, China Medical University Hospital, Taichung 40447, Taiwan. yachwu@mail.cmu.edu.tw.|School of Pharmacy, China Medical University, Taichung 40402, Taiwan. yachwu@mail.cmu.edu.tw.|Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan. yachwu@mail.cmu.edu.tw.
authors.forename: Yang-Chang
authors.initials: YC
authors.lastname: Wu
mesh_terms: D041721:3T3-L1 Cells / Q000187:drug effects; D000818:Animals; D050260:Carbohydrate Metabolism / Q000187:drug effects; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000378:metabolism; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D027723:Ipomoea batatas / Q000737:chemistry*; D051379:Mice; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D051381:Rats
chemical_list: D010936:Plant Extracts; D019869:Phosphatidylinositol 3-Kinases; D005947:Glucose
keywords: Ipomoea batatas; glucose uptake effect; purple sweet potato leaves