title: Metabolomic analysis of pancreatic beta cells following exposure to high glucose.
abstract: BACKGROUND
  Chronic exposure to hyperglycaemic conditions has been shown to have detrimental effects on beta cell function. The resulting glucotoxicity is a contributing factor to the development of type 2 diabetes. The objective of this study was to combine a metabolomics approach with functional assays to gain insight into the mechanism by which glucotoxicity exerts its effects.
  
  
  METHODS
  The BRIN-BD11 and INS-1E beta cell lines were cultured in 25 mM glucose for 20 h to mimic glucotoxic effects. PDK-2 protein expression, intracellular glutathione levels and the change in mitochondrial membrane potential and intracellular calcium following glucose stimulation were determined. Metabolomic analysis of beta cell metabolite extracts was performed using GC-MS, 1H NMR and 13C NMR.
  
  
  RESULTS
  Conditions to mimic glucotoxicity were established and resulted in no loss of cellular viability in either cell line while causing a decrease in insulin secretion. Metabolomic analysis of beta cells following exposure to high glucose revealed a change in amino acids, an increase in glucose and a decrease in phospho-choline, n-3 and n-6 PUFAs during glucose stimulated insulin secretion relative to cells cultured under control conditions. However, no changes in calcium handling or mitochondrial membrane potential were evident.
  
  
  CONCLUSIONS
  Results indicate that a decrease in TCA cycle metabolism in combination with an alteration in fatty acid composition and phosphocholine levels may play a role in glucotoxicity induced impairment of glucose stimulated insulin secretion.
  
  
  CONCLUSIONS
  Alterations in certain metabolic pathways play a role in glucotoxicity in the pancreatic beta cell.
authors.affiliation: UCD Conway Institute, UCD School of Agriculture, Food Science and Veterinary Medicine, UCD, Belfield, Dublin 4, Ireland.
authors.forename: Martina
authors.initials: M
authors.lastname: Wallace
authors.forename: Helena
authors.initials: H
authors.lastname: Whelan
authors.forename: Lorraine
authors.initials: L
authors.lastname: Brennan
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002952:Citric Acid Cycle / Q000187:drug effects*; D005227:Fatty Acids / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects; D005947:Glucose / Q000378:metabolism / Q000633:toxicity*; D005978:Glutathione / Q000378:metabolism; D007328:Insulin / Q000096:biosynthesis / Q000378:metabolism; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D055432:Metabolomics; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D010767:Phosphorylcholine / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D000081382:Pyruvate Dehydrogenase Acetyl-Transferring Kinase; D051381:Rats
chemical_list: D000596:Amino Acids; D005227:Fatty Acids; D007328:Insulin; D000081382:Pyruvate Dehydrogenase Acetyl-Transferring Kinase; D010767:Phosphorylcholine; D017346:Protein Serine-Threonine Kinases; D005978:Glutathione; D005947:Glucose; D002118:Calcium