Genome-Wide Association Study of Fluorescent Oxidation Products Accounting for Tobacco Smoking Status in Adults from the French EGEA Study

Postprandial Antioxidative Response to Ingestion of Formulated Date- and Fruit-Based Nutritional Bars by Healthy Individuals

Nutritional bars (NBs) are gaining popularity among healthy and athletic individuals, but postprandial antioxidative response has not been investigated. Therefore, the current study examined the postprandial alterations in total phenolic content (TPC), total antioxidant capacity (T-AOC), malondialdehyde (MDA), and Superoxide dismutase (SOD) in the plasma of healthy individuals after the ingestion of 140 g (510 Kcal) from formulated date-based bars (DBBs) or fruit-based bars (FBBs). Firstly, the free and bound phenolic contents (PCs) were determined to be 10.15 and 12.98 and 6.19 and 3.57 mg GAE g-1, respectively. FBBs were significantly higher in free PC than DBBs, while DBBs were considerably higher in bound PC than FBBs. Secondly, twenty participants with age, height, weight, body mass index (BMI), fat mass, and fat-free mass averages of 21.4 years, 170.0 cm, 66.3 kg, 22.9 kg m2, 14.5, and 29.2 kg, respectively, were subjected to metabolic experiments (ISRCTN19386758). Ingestion of 140 g of FBB or DBB resulted in 288.50 or 302.14 µg TPC mL-1 blood, respectively. Postprandial TPC content increased with time progression and peaked after 120 min. T-AOC contents averaged 22.63 and 23.61 U mL-1 before ingestion of FBBs or DBBs, respectively. The T-AOC content increased significantly 120 and 180 min after ingestion of DBBs, while no significant change was noted after consuming FBBs. A significant decrease in MDA content was observed 180 min after consuming DBBs, while no significant change was noted after consuming FBBs. SOD concentrations ranged from 193.99 to 201.07 U L-1 in FBBs and DBBs, respectively. No considerable response was noted up to 3 h after ingestion of FBBs. On the contrary, a significant response was found 120 min after consuming DBBs. Pearson's correlation coefficient indicated a highly significant positive correlation coefficient (p < 0.01) between T-AOC and either MDA or SOD, as well as between MDA and SOD. The principal component analysis demonstrated a strong and positive relationship between SOD and TPC at 60 and 120 min after DBB ingestion. In conclusion, the relative changes in postprandial responses in T-AOC and MDA did not significantly (p > 0.05) differ between DBBs and FBBs, except for TPC (p = 0.04, paired t-test) and SOD (p = 0.003, paired t-test). Further studies with an extended experimental time are needed to confirm the current findings.

The Role of Oxidative Stress and Antioxidants in Cardiovascular Comorbidities in COPD

Oxidative stress driven by several environmental and local airway factors associated with chronic obstructive bronchiolitis, a hallmark feature of COPD, plays a crucial role in disease pathomechanisms. Unbalance between oxidants and antioxidant defense mechanisms amplifies the local inflammatory processes, worsens cardiovascular health, and contributes to COPD-related cardiovascular dysfunctions and mortality. The current review summarizes recent developments in our understanding of different mechanisms contributing to oxidative stress and its countermeasures, with special attention to those that link local and systemic processes. Major regulatory mechanisms orchestrating these pathways are also introduced, with some suggestions for further research in the field.

Postprandial changes of oxidative stress biomarkers in healthy individuals

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/m², 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.

Assessing equivalent and inverse change in genes between diverse experiments

Background: It is important to identify when two exposures impact a molecular marker (e.g., a gene's expression) in similar ways, for example, to learn that a new drug has a similar effect to an existing drug. Currently, statistically robust approaches for making comparisons of equivalence of effect sizes obtained from two independently run treatment vs. control comparisons have not been developed. Results: Here, we propose two approaches for evaluating the question of equivalence between effect sizes of two independent studies: a bootstrap test of the Equivalent Change Index (ECI), which we previously developed, and performing Two One-Sided t-Tests (TOST) on the difference in log-fold changes directly. The ECI of a gene is computed by taking the ratio of the effect size estimates obtained from the two different studies, weighted by the maximum of the two p-values and giving it a sign indicating if the effects are in the same or opposite directions, whereas TOST is a test of whether the difference in log-fold changes lies outside a region of equivalence. We used a series of simulation studies to compare the two tests on the basis of sensitivity, specificity, balanced accuracy, and F1-score. We found that TOST is not efficient for identifying equivalently changed gene expression values (F1-score = 0) because it is too conservative, while the ECI bootstrap test shows good performance (F1-score = 0.95). Furthermore, applying the ECI bootstrap test and TOST to publicly available microarray expression data from pancreatic cancer showed that, while TOST was not able to identify any equivalently or inversely changed genes, the ECI bootstrap test identified genes associated with pancreatic cancer. Additionally, when investigating publicly available RNAseq data of smoking vs. vaping, no equivalently changed genes were identified by TOST, but ECI bootstrap test identified genes associated with smoking. Conclusion: A bootstrap test of the ECI is a promising new statistical approach for determining if two diverse studies show similarity in the differential expression of genes and can help to identify genes which are similarly influenced by a specific treatment or exposure. The R package for the ECI bootstrap test is available at https://github.com/Hecate08/ECIbootstrap.