A fluorescence method for the determination of plasma susceptibility to lipid peroxidation.
OBJECTIVE
We propose a fluorescence kinetics method for monitoring plasma susceptibility to peroxidation.


METHODS
Plasmatic peroxidation was induced by CuSO4 (500 microM), and fluorescence was measured every 30 min. Kinetics were represented by a sigmoidal curve from which it was possible to calculate the latency time (lag-time) and the propagation velocity (slope) of plasma peroxidation.


RESULTS
The lag-time monitored by the fluorescence kinetics method corresponded to the formation of thiobarbituric acid reactive substances, and to progressive depletion of polyunsaturated fatty acids and alpha-tocopherol. The mechanism of reaction appeared to be dependent upon plasmatic hydroperoxides, and independent of oxygen radicals. Plasma storage is possible for at least two months at -80 degrees C, and reproducibility of the method is very good.


CONCLUSIONS
Fluorescence kinetics provide a highly comprehensive picture of plasma susceptibility to peroxidation in comparison with the conventional measurements of anti- and pro-oxidant ratios.
Cervato
G
G
Department of Medical Chemistry and Biochemistry, L.I.T.A. Vialba, University of Milan, Milano, Italy. cestaro@imiucca.csi.unimi.it
Viani
P
P
Cazzola
R
R
Cestaro
B
B
D003300:Copper / Q000494:pharmacology; D005231:Fatty Acids, Unsaturated / Q000097:blood; D016166:Free Radical Scavengers / Q000494:pharmacology; D006801:Humans; D007700:Kinetics; D015227:Lipid Peroxidation / Q000187:drug effects*; D010949:Plasma / Q000378:metabolism*; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence / Q000379:methods*; D017392:Thiobarbituric Acid Reactive Substances / Q000378:metabolism; D014810:Vitamin E / Q000097:blood
D005231:Fatty Acids, Unsaturated; D016166:Free Radical Scavengers; D017392:Thiobarbituric Acid Reactive Substances; D014810:Vitamin E; D003300:Copper