Postprandial changes of oxidative stress biomarkers in healthy individuals
Fengyi Huang, Xue Shen, Yuzheng Zhang, Ann M. Vuong, Shuman Yang
Abstract
Food consumption induces oxidative stress in humans, but the changes in oxidative stress levels after a regular meal are still unclear. We conducted an experimental study on 20 healthy volunteers (10 males, 10 females), who matched in age (±2 years). They were given a regular diet (total energy of 704 kcal, which contains 75 g of carbohydrates, 35 g of protein, and 29 g of lipids) at 11:30 a.m. after a fast of over 12 h. We collected 6-repeated measures of venous blood samples at 2-h intervals via heparin anticoagulant tubes immediately after the meal (indicated as “0” h) and up to 10 h post-consumption. Biomarkers included plasma fluorescent products, plasma malondialdehyde, plasma total antioxidant capacity, and plasma superoxide dismutase. FlOPs were measured at three excitation/emission wavelengths (FlOP_320, FlOP_360, and FlOP_400). The average age and BMI for the twenty participants were 22.70 ± 1.98 years and 20.67 ± 2.34 kg/m 2 , respectively. Within 10 h after the meal, the overall trend of FlOPs were generally similar. There was no evidence of dose response for any of the three FlOPs (all P > 0.05). However, levels of MDA decreased with the time of fasting ( P linear and P quadratic < 0.05), with the biggest decrease occurring between 0 and 2 h post-meal. The overall trend of T-AOC and SOD levels also decreased with fasting time ( P linear and P quadratic < 0.05), though an increase was observed between 0 and 2 h following consumption. Levels of MDA, T-AOC, and SOD but not FlOPs, decreased with fasting time.