Although oxidative stress is considered the underlying mechanism by which dysfunctional metabolism occurs in obese subjects, there are few studies on oxidative stress in
overweight subjects. The objective of this study was to verify the influence of
metabolic syndrome (MetS) on oxidative stress and
antioxidant defense in
overweight subjects. There were 123 subjects (50 in the control group and 73 in the
overweight group) chosen to participate in this cross-sectional study. The control group included 50 healthy individuals with a BMI between 20 and 24.9 kg/m(2) and without MetS. The
overweight group included 73 subjects with a BMI between 25 and 29.9 kg/m(2).
Overweight subjects were divided into two groups: with MetS (29 subjects) and without MetS (44 subjects). Control group and
overweight group subjects without MetS showed no differences in oxidative stress parameters and total
antioxidant capacity (TRAP).
Overweight subjects with MetS had higher
hydroperoxide concentrations measured by chemiluminescence compared to the control group (P < 0.05), higher
hydroperoxide and
hydrogen peroxide concentrations determined by ferrous oxidation-
xylenol orange assay compared to
overweight subjects without MetS (P < 0.001), and higher
advanced oxidation protein product (
AOPP) concentrations (P < 0.001) compared to the other groups.
AOPP was directly correlated with
uric acid concentrations.
Overweight subjects with MetS had lower TRAP concentrations compared to the control group (P < 0.001). In conclusion, this study showed that
overweight subjects with MetS, in contrast to
overweight subjects without MetS, have a redox imbalance characterized by increased plasma oxidation and reduced
antioxidant capacity.