Proteomic analysis defines altered cellular redox pathways and advanced glycation end-product metabolism in glomeruli of db/db diabetic mice.
To attain a profile of protein expression during diabetes, we applied proteomic analysis to glomeruli of 160-day-old db/db diabetic and db/m nondiabetic mice. Glomerular proteins were extracted and separated by two-dimensional gel electrophoresis to construct a proteome map. Matrix-assisted laser desorption and ionization-time of flight mass spectrometry and peptide mass fingerprinting were used to identify 190 proteins. Of 105 analyzed spots, expression of 40 proteins, including the antioxidative enzymes peroxiredoxin 1 and 3, glutathione peroxidase 1, and SOD-1, was increased with diabetes, suggesting an adaptive response to oxidative stress associated with this diabetic model. However, activity of glutathione peroxidase and SOD was unaltered in glomeruli of diabetic mice. Expression of glyoxalase I was increased in glomeruli of diabetic mice. Because the cofactor for glyoxalase I, glutathione, is decreased in renal cortex of db/db mice, renal cortical glyoxalase I activity was measured in vitro with fixed amounts of exogenous glutathione. Glyoxalase I activity was decreased in renal cortex of db/db mice. These data indicate that diabetes-induced decreases in glyoxalase I activity are likely to be due to glutathione-dependent and -independent mechanisms and that increased expression of glyoxalase I may represent an insufficient adaptive response to increased methylglyoxal formation.
Barati
Michelle T
MT
Department of Medicine, University of Louisville, Louisville, Kentucky 40202, USA.
Merchant
Michael L
ML
Kain
Angela B
AB
Jevans
Anthony W
AW
McLeish
Kenneth R
KR
Klein
Jon B
JB
D000818:Animals; D003920:Diabetes Mellitus / Q000378:metabolism* / Q000473:pathology; D005260:Female; D005786:Gene Expression Regulation; D017127:Glycation End Products, Advanced / Q000378:metabolism*; D007672:Kidney Cortex / Q000378:metabolism / Q000473:pathology; D007678:Kidney Glomerulus / Q000378:metabolism* / Q000473:pathology; D007791:Lactoylglutathione Lyase / Q000378:metabolism*; D051379:Mice; D008815:Mice, Inbred Strains; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000502:physiology; D061105:Peroxiredoxin III; D054464:Peroxiredoxins / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D013482:Superoxide Dismutase / Q000378:metabolism; D000072105:Superoxide Dismutase-1
D017127:Glycation End Products, Advanced; C516116:Prdx3 protein, mouse; D061105:Peroxiredoxin III; D054464:Peroxiredoxins; C489899:Prdx1 protein, mouse; C515975:Prdx5 protein, mouse; C000606291:Sod1 protein, mouse; D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1; D007791:Lactoylglutathione Lyase