title: Short exposure of albumin to high concentrations of malondialdehyde does not mimic physiological conditions.
abstract: Malondialdehyde (MDA), a major lipid peroxidation product, spontaneously binds to, and modifies proteins. In vivo, proteins are physiologically exposed to micromolar MDA concentrations for long periods. In order to mimic this process in vitro, protein modification is often performed by short exposure to millimolar MDA concentrations, also in order to generate antigenic structures for antibody production. However, in our study, spectrophotometric and fluorimetric characteristics, electrophoretic migration, susceptibility to trypsin digestion and reactivity to antibodies indicated substantial differences between albumin incubated with millimolar MDA concentrations for a short period of time and albumin incubated with micromolar MDA concentrations for a long period of time. Therefore, our study showed that short incubation of albumin with millimolar MDA concentrations does not mimic the consequences of albumin exposure to long incubation with micromolar MDA concentrations. This casts doubts on the real possibility that antibodies, elicited with proteins modified with millimolar MDA concentrations for a short period, could detect all MDA-modified proteins in vivo. Moreover, natural antibodies against albumin, modified with micromolar MDA concentrations, have been detected in the serum of healthy blood donors, which appears to justify the existence of these kinds of modified proteins in vivo.
authors: Department of Experimental Medicine, Section of General Pathology, University of Genova, Italy.
authors: Susanna
authors: S
authors: Millanta
authors: Anna Lisa
authors: AL
authors: Furfaro
authors: Paolo
authors: P
authors: Carlier
authors: Bruno
authors: B
authors: Tasso
authors: Mariapaola
authors: M
authors: Nitti
authors: Cinzia
authors: C
authors: Domenicotti
authors: Patrizio
authors: P
authors: Odetti
authors: Maria Adelaide
authors: MA
authors: Pronzato
authors: Nicola
authors: N
authors: Traverso
mesh_terms: D000906:Antibodies / Q000276:immunology*; D015153:Blotting, Western; D004586:Electrophoresis; D004797:Enzyme-Linked Immunosorbent Assay; D015227:Lipid Peroxidation; D008315:Malondialdehyde / Q000737:chemistry* / Q000378:metabolism; D011506:Proteins / Q000276:immunology / Q000378:metabolism*; D012710:Serum Albumin, Bovine / Q000737:chemistry* / Q000276:immunology* / Q000378:metabolism; D013053:Spectrophotometry; D053802:Tryptases
chemical_list: D000906:Antibodies; D011506:Proteins; D012710:Serum Albumin, Bovine; D008315:Malondialdehyde; D053802:Tryptases