Methylglyoxal-induced covalent modifications of proteins: Is there any correlation with diabetic complications?

TOXI 93

Yuan Gao, yuan.gao@email.ucr.edu, Department of Chemistry, University of California at Riverside, 900 University Avenue, Riverside, CA 92521 and Yinsheng Wang, yinsheng.wang@ucr.edu, Department of Chemistry, University of California at Riverside, Mail Drop 027, Riverside, CA 92521-0403.
Methylglyoxal (MG) is a highly reactive alpha-oxoaldehyde that can be induced endogenously. Many factors could trigger its accumulation in vivo, including aging, hyperglycemia, oxidative stress, and uremia. MG could react with proteins and DNA to generate advanced glycation end products (AGEs). Proteins are predominantly modified on arginine residues and the dominant adduct was reported to be Ndelta-(5-hydro-5-methyl-4-imidazolon-2-yl)-ornithine (MG-H1). We systematically studied MG-induced modifications of hemoglobin and found that arginine residues in this protein could be modified by MG both in vitro and in vivo. The quantification data suggested that in vitro the levels of arginine modification correlated well with the MG concentration. We also identified and quantified the MG-induced modification of arginine residues in alpha-crystallin in vitro. Next we will examine the MG-modification of these two proteins extracted from diabetic mouse blood and lens samples with the overall goal being to investigate the correlation between protein MG-modification and diabetic complications.
 

Poster Session and Awards
6:00 PM-10:00 PM, Tuesday, August 21, 2007 BCEC -- 204 A/B, Poster

Division of Chemical Toxicology

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007