title: Vitamin C supplementation decreases insulin glycation and improves glucose homeostasis in obese hyperglycemic (ob/ob) mice.
abstract: The effects of dietary vitamin C supplementation on glucose homeostasis and insulin glycation were examined in adult lean and obese hyperglycemic (ob/ob) mice. In lean mice, supplementation of the drinking water with vitamin C (25 g/L) for 14 days did not affect food intake, fluid intake, glycated hemoglobin, plasma glucose, or plasma insulin concentrations. Total pancreatic insulin content and the percentage of glycated pancreatic insulin were also similar to control lean mice. In ob/ob mice, vitamin C supplementation caused significant reductions by 26% to 48% in food intake and fluid intake, glycated hemoglobin, plasma glucose, and insulin concentrations compared with untreated control ob/ob mice. The total insulin content and the extent of insulin glycation in the pancreas of ob/ob mice were also significantly decreased by 42% to 45% after vitamin C supplementation. This change was accompanied by a significant 80% decrease in the percentage of glycated insulin in the circulation of vitamin C-supplemented ob/ob mice. These data demonstrate that vitamin C supplementation can decrease insulin glycation and ameliorate aspects of the obesity-diabetes syndrome in ob/ob mice.
authors.affiliation: School of Biomedical Sciences, University of Ulster, Co. Londonderry, Northern Ireland.
authors.forename: Yasser H A
authors.initials: YH
authors.lastname: Abdel-Wahab
authors.forename: Finbarr P M
authors.initials: FP
authors.lastname: O'Harte
authors.forename: Mark H
authors.initials: MH
authors.lastname: Mooney
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Barnett
authors.forename: Peter R
authors.initials: PR
authors.lastname: Flatt
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000008:administration & dosage / Q000494:pharmacology*; D001786:Blood Glucose / Q000378:metabolism*; D001835:Body Weight / Q000187:drug effects; D019587:Dietary Supplements; D004327:Drinking Behavior; D002149:Energy Intake / Q000187:drug effects; D006442:Glycated Hemoglobin / Q000378:metabolism; D006706:Homeostasis / Q000187:drug effects; D006943:Hyperglycemia / Q000097:blood / Q000503:physiopathology*; D007328:Insulin / Q000097:blood / Q000378:metabolism; D000078790:Insulin Secretion; D051379:Mice; D008820:Mice, Obese; D009765:Obesity / Q000097:blood / Q000503:physiopathology*; D012016:Reference Values
chemical_list: D001205:Ascorbic Acid; D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007328:Insulin