Methyglyoxal administration induces modification of hemoglobin in experimental rats: An in vivo study

• Published in: Journal of photochemistry and photobiology. B, Biology Vol. 167; pp. 82 - 88
• Main Author: Banerjee, Sauradipta
• Format: Journal Article
• Language: English
• Published: Switzerland Elsevier B.V 01.02.2017; Elsevier BV
• Subjects: Absorbance; Adducts; Advanced glycation end products; Advanced glycosylation end products; Age; Amino acids; Animals; Calorimetry, Differential Scanning; Chromatography, Gel; Control stability; Diabetes; Diabetes mellitus; Experiments; Fingerprinting; Fluorescence; Glycation End Products, Advanced - chemistry; Glycosylation; Helicity; Heme proteins; Hemoglobin; Hemoglobins - chemistry; Hydroimidazolone; Hydrophobicity; In vivo methods and tests; Maillard-like reaction; Male; Methylglyoxal; Peptide mapping; Photobiology; Proteins; Pyruvaldehyde; Pyruvaldehyde - administration & dosage; Rats; Rats, Wistar; Rodents; Spectrometry, Fluorescence; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Spectrophotometry, Ultraviolet; Stability analysis; Hemoglobin; Methylglyoxal; Advanced glycation end products; Hydroimidazolone; Diabetes mellitus; Maillard-like reaction
• ISSN: 1011-1344; 1873-2682
• DOI: 10.1016/j.jphotobiol.2016.12.028

Methylglyoxal, a highly reactive α-oxoaldehyde, increases in diabetic condition and reacts with proteins to form advanced glycation end products (AGEs) following Maillard-like reaction. In the present study, the effect of methylglyoxal on experimental rat hemoglobin in vivo has been investigated with respect to structural alterations and amino acid modifications, after external administration of the α-dicarbonyl compound in animals. Different techniques, mostly biophysical, were used to characterize and compare methylglyoxal-treated rat hemoglobin with that of control, untreated rat hemoglobin. In comparison with methylglyoxal-untreated, control rat hemoglobin, hemoglobin of methylglyoxal-treated rats (32mg/kgbodywt.dose) exhibited slightly decreased absorbance around 280nm, reduced intrinsic fluorescence and lower surface hydrophobicity. The secondary structures of hemoglobin of control and methylglyoxal-treated rats were more or less identical with the latter exhibiting slightly increased α-helicity compared to the former. Compared to control rat hemoglobin, methylglyoxal-treated rat hemoglobin showed higher stability. Peptide mass fingerprinting analysis revealed modifications of Arg-31α, Arg-92α and Arg-104β of methylglyoxal-treated rat hemoglobin to hydroimidazolone adducts. The modifications thus appear to be associated with the observed structural alterations of the heme protein. Considering the increased level of methylglyoxal in diabetes mellitus as well as its high reactivity, AGE-induced modifications may have physiological significance. •Methylglyoxal reacts with of experimental rat hemoglobin to form advanced glycation end products (AGEs).•It modifies Arg-31α, Arg-92α and Arg-104β of hemoglobin to form AGE adduct hydroimidazolone.•AGE adducts were found to be associated with changes in structure and stability of the heme protein.