The effects of partial thiamin deficiency and oxidative stress (i.e., glyoxal and methylglyoxal) on the levels of alpha-oxoaldehyde plasma protein adducts in Fischer 344 rats.
We hypothesized that in marginal thiamin deficiency intracellular alpha-oxoaldehydes form macromolecular adducts that could possibly be genotoxic in colon cells; and that in the presence of oxidative stress these effects are augmented because of decreased detoxification of these aldehydes. We have demonstrated that reduced dietary thiamin in F344 rats decreased transketolase activity and increased alpha-oxoaldehyde adduct levels. The methylglyoxal protein adduct level was not affected by oral glyoxal or methylglyoxal in the animals receiving thiamin at the control levels but was markedly increased in the animals on a thiamin-reduced diet. These observations are consistent with our suggestion that the induction of aberrant crypt foci with marginally thiamin-deficient diets may be a consequence of the formation of methylglyoxal adducts.
Shangari
Nandita
N
Department of Pharmaceutical Sciences, University of Toronto, ON, Canada.
Depeint
Flore
F
Furrer
Rudolf
R
Bruce
W Robert
WR
O'Brien
Peter J
PJ
D000447:Aldehydes / Q000097:blood* / Q000737:chemistry; D000818:Animals; D001798:Blood Proteins / Q000032:analysis* / Q000737:chemistry / Q000187:drug effects; D015536:Down-Regulation; D006037:Glyoxal / Q000097:blood / Q000494:pharmacology; D008297:Male; D018384:Oxidative Stress; D011765:Pyruvaldehyde / Q000097:blood / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344; D013831:Thiamine / Q000494:pharmacology; D013832:Thiamine Deficiency / Q000201:enzymology*; D014174:Transketolase / Q000378:metabolism*
D000447:Aldehydes; D001798:Blood Proteins; D006037:Glyoxal; D011765:Pyruvaldehyde; D014174:Transketolase; D013831:Thiamine