Quantitation of acrolein and crotonaldehyde modified albumin.
Gan-JC; Oandasan-A; Ansari-GAS
Toxicologist 1992 Feb; 12(1):190
Previous studies from this laboratory has shown that acrolein modifies amino, sulfhydryl and imidazole functional groups of protein mainly through Michael addition reaction. These modifications were quantitated by amino acid analysis. The present study was undertaken to develop a rapid and sensitive method for the estimation of acrolein adducts of albumin which can subsequently be used as a marker of acrolein exposure. Human plasma albumin samples were incubated with increasing concentrations of acrolein (0.025 to 10 micromole/ml) at 37 degrees C in 0.1M phosphate buffer, pH 7.2, for 2 hr. After exhaustive dialysis, the modified protein was treated with 3H-NaBH4 to reduce the aldehyde adduct to corresponding alcohol. The radioactivity measured after exhaustive dialysis was express as nmoles of carbonyl function/mg protein. The response was found to be linear in the range studied. This method is about four times as sensitive as amino acid analysis in detecting covalent binding of acrolein to albumin. Although not as reactive, crotonaldehyde (2-butanal, a metabolite of butadiene) gave a similar capacity to bind covalently with albumin as acrolein. Efficacy of this method needs to be established under in·vivo conditions.
Chemical-processing; Chemical-reactions; Chemical-structure; Chemical-synthesis; Exposure-assessment; Radioactive-measurement; Proteins; Protein-synthesis
The Toxicologist. Society of Toxicology 31st Annual Meeting, February 23-27,1992, Seattle, Washingtion
University of Texas Medical Branch, Galveston, Texas