title: LBP-4a improves insulin resistance via translocation and activation of GLUT4 in OLETF rats.
abstract: Lycium barbarum polysaccharide (LBP) has been shown to ameliorate insulin resistance, but the identification of compounds from LBP and the mechanisms have not been clarified. In this study, LBP-4a was purified from Lycium barbarum by DEAE cellulose and Sephadex G-100 column chromatography, and the effects of LBP-4a on insulin resistance were investigated. The results indicated that LBP-4a caused translocation of the glucose transporter isoform 4 (GLUT4) to the cell surface, which in turn stimulated glucose uptake, and the effect was sensitive to wortmannin, an inhibitor of phosphoinositol 3-kinase (PI3-K), and SB203580, an inhibitor of p38 mitogen activated protein kinase (p38 MAPK (α, β)). Furthermore, the effects of LBP-4a on p38 MAPK activities were abrogated by pretreatment of rat adipocytes using SB203580. In summary, LBP-4a improved insulin resistance via translocation and activation of GLUT4 in OLETF rats, and the activation of PI3-K and p38 MAPK contributed to these effects.
authors.affiliation: Department of Pharmaceutical Engineering, College of Life Science & Biotechnology, Heilongjiang August First Land Reclamation University, Daqing High-Tech Industrial Development Zone, 163319, P. R. China.
authors.forename: Rui
authors.initials: R
authors.lastname: Zhao
authors.forename: Bing
authors.initials: B
authors.lastname: Qiu
authors.forename: Qingwang
authors.initials: Q
authors.lastname: Li
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.forename: Hui
authors.initials: H
authors.lastname: Zhao
authors.forename: Zhibao
authors.initials: Z
authors.lastname: Chen
authors.forename: Yaping
authors.initials: Y
authors.lastname: Cai
authors.forename: Hongsheng
authors.initials: H
authors.lastname: Ruan
authors.forename: Wenzhong
authors.initials: W
authors.lastname: Ge
authors.forename: Xiaoliang
authors.initials: X
authors.lastname: Zheng
mesh_terms: D017667:Adipocytes / Q000187:drug effects / Q000378:metabolism; D000818:Animals; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy* / Q000378:metabolism; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage* / Q000302:isolation & purification; D051275:Glucose Transporter Type 4 / Q000378:metabolism*; D006801:Humans; D007333:Insulin Resistance; D032305:Lycium / Q000737:chemistry*; D008297:Male; D021381:Protein Transport; D051381:Rats; D020334:Rats, Inbred OLETF
chemical_list: D004365:Drugs, Chinese Herbal; D051275:Glucose Transporter Type 4; C500223:lycium barbarum polysaccharide