title: Oral administration of soybean peptide Vglycin normalizes fasting glucose and restores impaired pancreatic function in Type 2 diabetic Wistar rats.
abstract: Vglycin, a natural 37-residue polypeptide isolated from pea seeds in which six half-cysteine residues are embedded in three pairs of disulfide bonds, is resistant to digestive enzymes and has antidiabetic potential. To investigate the pharmacological activity of Vglycin in vivo and to examine the mechanisms involved, the therapeutic effect of Vglycin in diabetic rats was examined. Diabetes was induced in Wistar rats by high-fat diet and multiple streptozotocin intraperitoneal injections. Diabetic rats were treated daily with Vglycin for 4 weeks. Body weight, food intake, fasting plasma glucose and insulin levels were assayed weekly. Glucose and insulin tolerance tests were conducted on Day 29. Subsequently, levels of p-Akt in the liver and pancreas and cleaved PARP, Pdx-1 and insulin in the pancreas were detected by immunoblotting. The morphology of the pancreas and the insulin expression in the pancreas were analyzed by hematoxylin-eosin staining and immunohistochemistry, respectively. Furthermore, human liver-derived cell lines were used to explore the in vitro effects of Vglycin on insulin sensitivity and glucose uptake. Chronic treatment with Vglycin normalized fasting glucose levels in diabetic rats. The improvement in glucose homeostasis and the increased insulin sensitivity mediated by restored insulin signaling likely contributed to decreased food intake and reduced body weight. Vglycin protected pancreatic cells from damage by streptozotocin. Although insulin synthesis and secretion in impaired β-cell were not significantly elevated, islets morphology was improved in the Vglycin-treated groups. These results suggest that Vglycin could be useful in Type 2 diabetes for restoring impaired insulin signaling, glucose tolerance and pancreatic function.
authors.affiliation: Key Laboratory of Molecular Biophysics of Ministry of Education, School of Life Science and Technology, Wuhan, P.R. China.
authors.forename: Hua
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Department of Oncology, Wuhan Pu-Ai Hospital, Tong ji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China.
authors.forename: Jueping
authors.initials: J
authors.lastname: Feng
authors.affiliation: Key Laboratory of Molecular Biophysics of Ministry of Education, School of Life Science and Technology, Wuhan, P.R. China.
authors.forename: Zhongxia
authors.initials: Z
authors.lastname: Du
authors.affiliation: Department of Clinical Laboratory, the Second Staff Hospital of Wuhan Iron and Steel (Group) Corporation, Wuhan, P.R. China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhen
authors.affiliation: Department of Oncology, Wuhan Pu-Ai Hospital, Tong ji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China.
authors.forename: Mei
authors.initials: M
authors.lastname: Lin
authors.affiliation: College of Health Science, Wuhan Sports University, Wuhan, P.R. China.
authors.forename: Shaohui
authors.initials: S
authors.lastname: Jia
authors.affiliation: Department of narcotics control, Chongqing Police College, Chongqing City, P.R. China.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.affiliation: College of Life Science and Technology, Hubei Engineering University, Xiaogan, P.R. China.
authors.forename: Xinyuan
authors.initials: X
authors.lastname: Huang
authors.affiliation: Department of Molecular Medicine, Karolinska Hospital, Stockholm, Sweden.
authors.forename: Claes-Goran
authors.initials: CG
authors.lastname: Ostenson
authors.affiliation: Key Laboratory of Molecular Biophysics of Ministry of Education, School of Life Science and Technology, Wuhan, P.R. China. Electronic address: zwchen@mail.hust.edu.cn.
authors.forename: Zhengwang
authors.initials: Z
authors.lastname: Chen
mesh_terms: D000284:Administration, Oral; D000595:Amino Acid Sequence; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000503:physiopathology*; D005215:Fasting; D006706:Homeostasis / Q000187:drug effects; D007333:Insulin Resistance; D007515:Islets of Langerhans / Q000187:drug effects* / Q000503:physiopathology; D008969:Molecular Sequence Data; D051381:Rats; D017208:Rats, Wistar; D030262:Soybean Proteins / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D013025:Glycine max / Q000737:chemistry*
chemical_list: D001786:Blood Glucose; D030262:Soybean Proteins; C000596330:Vglycin, soybean
keywords: Glucose homeostasis; Restore; Type 2 diabetes mellitus; Vglycin