Oxidative stress markers
Native thiol (NT), total thiol (TT) and disulfide (DS) levels were
analyzed according to the method of Erel and
Neselioglu.8 DS (S-S) levels were determined by
calculating half of the difference between TT (-SH+S-S) and NT (-SH);
subsequently, DS/NT, DS/TT, and NT/TT ratios were
calculated.8
Serum TAS and TOS levels were measured using the automated colorimetric
method developed by Erel O.13,14 After measuring the
TOS and TAS levels, as a further good marker of oxidative stress, the
oxidative stress index (OSI) was calculated as
follows: OSI= [(TOS /TAS)×100].15