Biology Reference
In-Depth Information
2.8 What Should We do to Evaluate
the Effect of Antioxidant Intake on
Antioxidant Capacity in Vivo ? Some
Recommendations
Tip 2. It is highly recommended to measure
some oxidative stress biomarkers: analysis of
antioxidants in plasma and tissues. You can
measure the ratio of endogenous antioxidant
systems, for instance, (GSH/GSSH; UQ/UQH 2 ),
or enzymes (CAT, SOD, GPx, GST, Prx) or vita-
min E/C levels, carotenes, etc., or analysis of
oxidation products (y-tocopheryl quinone,
5-nitro-y-tocopherol, allantoin, nitrotyrosine).
Tip 3. Try to measure some biomarkers of
damage ascribed to ROS. Damage to lipid,
DNA and protein substrates could be assessed
by means of: lipids (TBARS and MDA levels,
DODE, HETE, conjugated dienes, isoprostanes,
oxidized LDL, oxy-sterols); DNA (specific ROS
damage to DNA could be evidenced by HNE,
Comet assay, thyamine glycol, 5-hydroxyade-
nine, 8-hydroxyguanine); and proteins (spe-
cific ROS damage to proteins: carbonyls, MPO,
lipofucsin, AGEs, oxidated thiols).
The in vitro assays described above actually
reflect the reductive capacity of the polyphe-
nolic molecules. To be considered an anti-
oxidant with biological relevance, substances
must be able to:
1. Scavenge or inhibit the production of
free radicals locally generated.
2. Result in significant changes in oxidative
stress biomarkers or increases in the antioxi-
dant capacity of plasma or specific tissue.
When designing an intervention study
with polyphenolic antioxidants, it is there-
fore recommended to include assays for
total antioxidant capacity and levels of oxi-
dative stress biomarkers. The following tips
provide some recommendations for the
proper assessment of the impact of con-
sumption of antioxidants in vivo :
Acknowledgements
Tip 1. Always try to measure serum or
plasma antioxidant capacity indexes before
and after antioxidant intake (TAC; ORAC;
FRAP; ABTS; CUPRAC). Express your
results as Trolox equivalents.
Edgar Pastene gratefully acknowledges the
financial support of Chile Science Founda-
tionCONICYT-FONDECYTgrantN°11110442
and the Universidad de Concepción Basal
Project PFB-27 (PFT-014).
References
Aguayo, C., 2011. Efecto de la halogenación de quercetina-3-O-ramnoglucósido (Rutina) sobre la
producción de especies reactivas del oxígeno liberadas por fagocitos en respuesta a
Helicobacter pylori , Tesis Química y Farmacia. Universidad de Concepción, Concepción,
Chile.
Alberto, M., Canavosio, M. & Nadra, M.M.D., 2006. Antimicrobial effect of polyphenols from apple
skins on human bacterial pathogens. Electronic Journal of Biotechnology 9, 205-209.
Althaus, J.S., Andrus, P.K., Williams, C.M., Vonvoigtlander, P.F., Cazers, A.R. & Hall, E.D., 1993. The
use of salicylate hydroxylation to detect hydroxyl radical generation in ischemic and traumatic
brain injury - reversal by tirilazad mesylate (U-74006f). Molecular and Chemical Neuropathology
20, 147-162.
Andersen, J. K., 2004. Oxidative stress in neurodegeneration: cause or consequence? Nature Medicine
10, S18-S25.
Aoshima, H., Okita, Y., Hossain, S.J., Fukue, K., Mito, M., et al ., 2005. Effect of 3-O-octanoyl-(+)-catechin
on the responses of GABA(A) receptors and Na+/glucose cotransporters expressed in Xenopus
oocytes and on the oocyte membrane potential. Journal of Agricultural and Food Chemistry 53,
1955-1959.
Apak, R., Guclu, K., Ozyurek, M. & Karademir, S.E., 2004. Novel total antioxidant capacity index
for dietary polyphenols and vitamins C and E, using their cupric ion reducing capability in
the presence of neocuproine: CUPRAC method. Journal of Agricultural and Food Chemistry
52, 7970-7981.
 
Search WWH ::




Custom Search