A metabonomic and proteomic analysis of changes in IMCD3 cells chronically adapted to hypertonicity.
BACKGROUND
The genomic response to adaptation of IMCD3 cells to hypertonicity results in both upregulation and downregulation of a variety of genes.


METHODS
The present study was undertaken to assess the metabonomic and proteomic response of IMCD3 cells that have been chronically adapted to hypertonicity (600 and 900 mosm/kg H(2)O) as compared to cells under isotonic conditions.


RESULTS
Adaptation of IMCD3 cells to hypertonic conditions resulted in a change of a wide range of organic osmolytes, including sorbitol (+8,291%), betaine (+1,099%), myo-inositol (+669%), taurine (+113%) and glycerophosphorylcholine (+61%). Evaluation of the polyol pathway for sorbitol production revealed a reduction in sorbitol dehydrogenase and an increase in aldose reductase mRNA in adapted cells. Proteome analysis revealed increased expression of six glycolytic proteins, including malic enzyme and pyruvate carboxylase, indicating the activation of the pyruvate shunt and changes in glucose metabolism. This study showed that the observed reduction in cell replication could possibly reflect a redirection of cellular energy from cell growth and replication to maintenance of intracellular ion levels in chronically adapted cells.


CONCLUSIONS
The combined metabonomic and proteomic analysis was shown to be a very helpful tool for the analysis of the effects caused by chronic adaptation to hypertonicity. It made it possible to better evaluate the importance of certain changes that occur in the process of adaptation.
Klawitter
Jost
J
Department of Anesthesiology, School of Medicine, University of Colorado Health Sciences Center, Denver, CO 80262, USA.
Rivard
Christopher J
CJ
Brown
Lewis M
LM
Capasso
Juan M
JM
Almeida
Nestor E
NE
Maunsbach
Arvid B
AB
Pihakaski-Maunsbach
Kaarina
K
Berl
Tomas
T
Leibfritz
Dieter
D
Christians
Uwe
U
Chan
Laurence
L
D000222:Adaptation, Physiological; D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D015153:Blotting, Western; D002460:Cell Line; D049109:Cell Proliferation; D015180:Electrophoresis, Gel, Two-Dimensional; D004734:Energy Metabolism; D004798:Enzymes / Q000235:genetics / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D007679:Kidney Medulla / Q000201:enzymology / Q000378:metabolism* / Q000648:ultrastructure; D007685:Kidney Tubules, Collecting / Q000201:enzymology / Q000378:metabolism* / Q000648:ultrastructure; D051379:Mice; D046529:Microscopy, Electron, Transmission; D008928:Mitochondria / Q000378:metabolism; D019906:Nuclear Magnetic Resonance, Biomolecular; D009997:Osmotic Pressure; D010641:Phenotype; D010710:Phosphates / Q000378:metabolism; D011108:Polymers / Q000378:metabolism; D040901:Proteomics / Q000379:methods; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012462:Saline Solution, Hypertonic
D000596:Amino Acids; D004798:Enzymes; D010710:Phosphates; D011108:Polymers; D012462:Saline Solution, Hypertonic; C024617:polyol; D005947:Glucose