Article Text
Abstract
Introduction/Background The goal of study was to examine the effects of alpha-lipoic acid (LA) supplementation on oxidative stress markers in patients with low-grade squamous intraepithelial lesion (LSIL).
Methodology One hundred (100) patients diagnosed with LSIL were randomized to receive 600 mg/day of LA (treatment group-T) or placebo (control-C) for three months. Ninety (90) patients finished the study (40 controls and 50 treated). Venous blood was collected for analysis of oxidative stress markers (plasma ferric reducing power (FRAP), superoxide dismutase (SOD) activity, reduced glutathione levels (GSH) and malondialdehyde levels (MDA)) at baseline and at 90th day of supplementation. All patients were instructed to fulfil validated food frequency questionary (FFQs) to investigate average intake of food derived antioxidants (number of fruit/vegetable portions and intake of nutrients with antioxidative potency). The normality of the distribution of obtained data was tested using the D’Agostino – Pearson test. Obtained values were presented as median ± 95% confidence range and comparison of results (before-after supplementation/control-tested) was performed using the Mann-Whitney U test for the significance level p <0.05.
Results There were no significant differences between baseline FRAP, SOD, GSH and MDA levels between patients in control and treatment group. LA supplementation didn`t significantly impact SOD GSH or MDA levels but it increased TAC values, although observed changes were not statistically significant (p=0.0893). FFQ analysis revealed vegetable intake significantly affected baseline FRAP values-they were significantly lower in the group of patients with the lowest vegetable intake (4th quartile) in comparison to the group with the highest vegetable intake (1st quartile) (p=0.0116).
Conclusion LA supplementation in investigated regime (300 mg/day for 3 months) was not effective in improving oxidative status parameters in patients with LSIL. Analysis of FFQs revealed that nutritional patterns, rather than supplementation with antioxidant, can have significant impact on plasma antioxidant status in LSIL patients.