Obesity and systemic oxidative stress: clinical correlates of oxidative stress in the Framingham Study

Association of serum levels of antioxidant micronutrients with mortality in US adults: National Health and Nutrition Examination Survey 1999-2002

OBJECTIVE

To examine associations between serum antioxidant levels and mortality (all-cause, cancer and CVD) among US adults.

DESIGN

We examined the risk of death from all-cause and cause-specific mortality associated with serum antioxidant (vitamin E and carotenoids) and vitamin A levels using Cox regression models to estimate hazards ratios (HR) and 95 % CI.

SETTING

The National Health and Nutrition Examination Survey (NHANES) 1999-2002 was followed up through 31 December 2015.

PARTICIPANTS

The NHANES 1999-2002 cohort included 8758 participants aged ≥ 20 years. Serum carotenoid levels were only assessed for the 1999-2000 cycle. Therefore, sample size for each assessed antioxidant ranged from 4633 to 8758.

RESULTS

Serum vitamin E level was positively associated with all-cause mortality (HR = 1·22, 95 % CI 1·04, 1·43, highest v. lowest quartile). No other antioxidants were associated with mortality in overall analysis. In race/ethnicity-specific analyses, high vitamin E and α-tocopherol levels were associated with increased risk of all-cause mortality among non-Hispanic Whites. Among non-Hispanic Blacks, serum α-tocopherol level was associated with decreased risk of cancer mortality (HR = 0·30, 95 % CI 0·12, 0·75, third v. first quartile) and total carotenoid levels with reduced risk of CVD mortality (HR = 0·26; 95 % CI 0·07, 0·97, second v. lowest quartile). Hispanics with high β-carotene levels had reduced risk of CVD mortality.

CONCLUSIONS

Serum antioxidant levels may be related to mortality; these associations may differ by race/ethnicity and appeared to be non-linear for all-cause and cause-specific mortality. Further studies are needed to confirm our results.

Monosodium glutamate causes hepato-cardiac derangement in male rats

People in the fast-food era rely on pre-packaged foods and engage in limited physical activity, which leads to a shift in eating patterns. Monosodium glutamate (MSG), a dietary ingredient used in this sort of cuisine, has been found to be hazardous to both experimental animals and humans. The objective of this study was to explore at the unnecessary changes caused by consuming MSG in secret and exceeding the recommended dosage. Hence, we decided to evaluate the impact of MSG by using three different doses (200, 400, and 600 mg/kg body weight orally) for 28 days in rats. We uncovered that all three MSG dosages result in a rise in body weight, dyslipidemia, inflammatory response, and hepato-cardiac marker enzymes, all of which imply hepatic and cardiac toxicity. Furthermore, changes in redox status suggest oxidative stress, which was higher in all three MSG dosages although not as much as in the MSG-600 group when compared to control. Such effects eventually manifested themselves in tissue architecture of the liver and heart, resulting in severe hepato-cardiac derangement, but the degree of tissue damage was greater in the MSG-600 group. As a result, it is possible that MSG has a negative influence on the liver and heart. However, the MSG-600 group showed a substantial effect, indicating that MSG should not be used in food preparation. Therefore, the findings of the study may aid in the formulation of health-care strategies and serve as a warning to the general public regarding the use of MSG in daily diet.

Sex difference in the interrelationship between TNF-α and oxidative stress status in first-episode drug-naïve schizophrenia

BACKGROUND

Increasing evidence indicates that dysregulated TNF-α and oxidative stress (OxS) contribute to the pathophysiology of schizophrenia. Additionally, previous evidence has demonstrated sex differences in many aspects of schizophrenia including clinical characteristics, cytokines, and OxS markers. However, to the best of our knowledge, there is no study investigating sex differences in the association between TNF-α, the OxS system, and their interaction with clinical symptoms in schizophrenia patients, especially in first-episode drug-naïve (FEDN) patients.

METHODS

A total of 119 FEDN schizophrenia patients and 135 healthy controls were recruited for this study. Serum TNF-α, superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and malondialdehyde (MDA) were measured. The Positive and Negative Syndrome Scale (PANSS) was applied to evaluate psychotic symptoms. Two-way ANOVA, partial correlation analysis, and multivariate regression analysis were performed.

RESULTS

A sex difference in MDA levels was demonstrated only in healthy controls (F = 7.06, pBonferroni = 0.045) and not seen in patients. Furthermore, only male patients had higher MDA levels than male controls (F = 8.19, pBonferroni = 0.03). Additionally, sex differences were observed in the association of TNF-α and MDA levels with psychotic symptoms (all pBonferroni < 0.05). The interaction of TNF-α and MDA was only associated with general psychopathology symptom in male patients (B = - 0.07, p = 0.02).

CONCLUSION

Our results demonstrate the sex difference in the relationship between TNF-α, MDA, and their interaction with psychopathological symptoms of patients with schizophrenia.

The pivotal role of Nrf2 activators in adipocyte biology

Adipose tissue is instrumental in maintaining metabolic homeostasis by regulating energy storage in the form of triglycerides. In the case of over-nutrition, adipocytes favorably regulate lipogenesis over lipolysis and accumulate excess triglycerides, resulting in increased adipose tissue mass. An abnormal increase in hypertrophic adipocytes is associated with chronic complications such as insulin resistance, obesity, diabetes, atherosclerosis and nonalcoholic fatty liver disease. Experimental studies indicate the occurrence of oxidative stress in the pathogenesis of obesity. A common underlying link between increasing adipose tissue mass and oxidative stress is the Nuclear Factor Erythroid 2-related factor 2 (Nrf2), Keap1-Nrf2-ARE signaling, which plays an indispensable role in metabolic homeostasis by regulating oxidative and inflammatory responses. Additionally, Nrf2 also activates CCAAT/enhancer-binding protein α, (C/EBP-α), C/EBP-β and peroxisome proliferator-activated receptor γ (PPARγ) the crucial pro-adipogenic factors that promote de novo adipogenesis. Hence, at the forefront of research is the quest for prospecting novel compounds to modulate Nrf2 activity in the context of adipogenesis and obesity. This review summarizes the molecular mechanism behind the activation of the Keap1-Nrf2-ARE signaling network and the role of Nrf2 activators in adipocyte pathophysiology.

The relation between dietary phytochemical index and metabolic syndrome and its components in a large sample of Iranian adults: a population-based study

Background

Despite the protective effects of foods being rich in phytochemicals against chronic diseases, this issue is still poorly understood. The aim of this study was to investigate the association between Dietary Phytochemical Index (DPI) and metabolic syndrome (MetS) and its components.

Methods

This cross-sectional study focused on adults aged between 20 and 70years. The dietary intake was assessed using a validated and reliable food frequency questionnaire. DPI was calculated based on dietary energy, derived from phytochemical-rich food sources (kcal) per total daily energy intake (kcal). The odds ratio of MetS and its components were assessed across DPI quartiles by logistic regression models.

Results

After adjustment for all potential confounders, the risk of MetS (OR: 0.63, 95% CI = 0.41–0.96) and elevated blood pressure (OR: 0.62, 95% CI = 0.40–0.96) in the second category of DPI decreased significantly as compared to that in the first category. Subjects in the second and fourth quartiles of DPI with adjusting for age, sex and total energy intake revealed 30 and 25% lower risk of abdominal obesity, respectively. After full adjustment for confounders, the analysis stratified by sex showed women in the highest quartile of DPI had 59% lower risk of MetS (OR: 0.41, 95% CI = 0.22–0.76) as compared to those in the lowest quartile of DPI.

Conclusions

Greater adherence to phytochemical-rich diet could reduce odds of MetS and some components, especially in women. Further studies with intervention approaches are recommended.

Role of adipocyte-derived extracellular vesicles in vascular inflammation

Extracellular vesicles (EVs) are nanometre-sized vesicles released from most cells, including adipocytes. Relatively little is known about adipocyte-derived EVs (ADEVs) in comparison to other EV subtypes, though interest in ADEVs as potential paracrine and endocrine communicators of adipose tissue in obesity is building. Current evidence indicates that ADEVs contribute to the development of adipose tissue dysfunction; a key feature of obese adipose tissue that it is associated with obesity-related comorbidities including cardiovascular disease (CVD). This review summarises our current knowledge of ADEVs in the development of adipose tissue dysfunction and the potential of ADEVs to disrupt redox signalling and exert vascular effects that may exacerbate CVD in obesity.

The Interplay Between Mitochondrial Reactive Oxygen Species, Endoplasmic Reticulum Stress, and Nrf2 Signaling in Cardiometabolic Health

Significance: Mitochondria-derived reactive oxygen species (mtROS) are by-products of normal physiology that may disrupt cellular redox homeostasis on a regular basis. Nonetheless, failure to resolve sustained mitochondrial stress to mitigate high levels of mtROS might contribute to the etiology of numerous pathological conditions, such as obesity, insulin resistance, and cardiovascular disease (CVD). Recent Advances: Notably, recent studies have demonstrated that moderate mitochondrial stress might result in the induction of different stress response pathways that ultimately improve the organism's ability to deal with subsequent stress, a process termed mitohormesis. mtROS have been shown to play a key role in regulating this adaptation. Critical Issue: mtROS regulate the convergence of different signaling pathways that, when disturbed, might impair cardiometabolic health. Conversely, mtROS seem to be required to mediate activation of prosurvival pathways, contributing to improved cardiometabolic fitness. In the present review, we will primarily focus on the role of mtROS in the activation of the nuclear factor erythroid 2-related factor 2 (Nrf2) antioxidant pathway and examine the role of endoplasmic reticulum (ER) stress in coordinating the convergence of ER stress and oxidative stress signaling through activation of Nrf2 and activating transcription factor 4 (ATF4). Future Directions: The mechanisms underlying cardiometabolic protection in response to mitochondrial stress have only started to be investigated. Integrated understanding of how mtROS and ER stress cooperatively promote activation of prosurvival pathways might shed mechanistic insight into the role of mitohormesis in mediating cardiometabolic protection and might inform future therapeutic avenues for the treatment of metabolic diseases contributing to CVD. Antioxid. Redox Signal. 35, 252-269.

Selenium, as selenite, prevents adipogenesis by modulating selenoproteins gene expression and oxidative stress-related genes

OBJECTIVES

The aim of this study was to assess the effect of the micronutrient selenium, as inorganic selenite, on adipocytes differentiation, and to identify underlying molecular mechanisms to advance the understanding of basic cellular mechanisms associated with adipogenesis.

METHODS

The effect of sodium selenite (Na₂SeO₃) on cell viability (bromide 3-[4,5-dimethylthiazol-2-yl]-2,5-difeniltetrazol [MTT] assay) in preadipocytes, lipid accumulation (oil red O [ORO] assay) and intracellular reactive oxygen species (ROS, [NBT assay]) in mature adipocytes, as well as explore molecular mechanisms via gene expression analyses (real-time quantitative polymerase chain reaction), before and after differentiation, was investigated using 3T3-L1 murine preadipocytes.

RESULTS

Selenite (100, 200, and 400 nM) significantly decreased lipid accumulation during differentiation compared with untreated adipocytes (P < 0.05, 0.001, and 0.01, respectively). Preadipocytes exposure (48 h) to selenite caused an increase in glutathione peroxidase 1 (Gpx1) gene expression in a dose-dependent manner. Adipogenesis significantly increased intracellular reactive oxygen species levels (P < 0.05) while decreasing gene expression of antioxidant enzymes (Gpx1: P < 0.05) and significantly increasing gene expression of regulators of lipid catabolism (type II iodothyronine deiodinase [Dio2], P < 0.01) and markers of differentiation (eg, selenium-binding protein 1 [Selenbp1], peroxisome proliferator activated receptor gamma [Pparg], CCAAT/enhancer binding protein alpha [Cebpa], and fatty acid binding protein 4 [Fab4]) compared with preadipocytes (P < 0.01, 0.01, 0.01, and 0.001, respectively). Selenite exposure (200 nM) caused a significant increase in Gpx1, selenoprotein W (Selenow) and selenoprotein P (Selenop) gene expression, in adipocytes compared with untreated ones (P < 0.01, 0.001, and 0.05, respectively) with a significant decrease in heme oxygenase 1 (Ho-1), cyclooxygenase 2 (Cox2), Dio2, and Fabp4 gene expression (P < 0.001, 0.05, 0.05, and 0.01, respectively).

CONCLUSIONS

Selenium, as selenite, prevented adipogenesis through increasing antioxidant selenoprotein expression, leading to decreased inflammatory markers and, subsequently, to a decrease in differentiation and lipid deposition. These findings, if demonstrated in vivo, could provide valuable data for novel dietary approaches to prevent obesity.

Reversal of Insulin Resistance in Overweight and Obese Subjects by trans-Resveratrol and Hesperetin Combination-Link to Dysglycemia, Blood Pressure, Dyslipidemia, and Low-Grade Inflammation

The dietary supplement, trans-resveratrol and hesperetin combination (tRES-HESP), induces expression of glyoxalase 1, countering the accumulation of reactive dicarbonyl glycating agent, methylglyoxal (MG), in overweight and obese subjects. tRES-HESP produced reversal of insulin resistance, improving dysglycemia and low-grade inflammation in a randomized, double-blind, placebo-controlled crossover study. Herein, we report further analysis of study variables. MG metabolism-related variables correlated with BMI, dysglycemia, vascular inflammation, blood pressure, and dyslipidemia. With tRES-HESP treatment, plasma MG correlated negatively with endothelial independent arterial dilatation (r = -0.48, p < 0.05) and negatively with peripheral blood mononuclear cell (PBMC) quinone reductase activity (r = -0.68, p < 0.05)-a marker of the activation status of transcription factor Nrf2. For change from baseline of PBMC gene expression with tRES-HESP treatment, Glo1 expression correlated negatively with change in the oral glucose tolerance test area-under-the-curve plasma glucose (ΔAUGg) (r = -0.56, p < 0.05) and thioredoxin interacting protein (TXNIP) correlated positively with ΔAUGg (r = 0.59, p < 0.05). Tumor necrosis factor-α (TNFα) correlated positively with change in fasting plasma glucose (r = 0.70, p < 0.001) and negatively with change in insulin sensitivity (r = -0.68, p < 0.01). These correlations were not present with placebo. tRES-HESP decreased low-grade inflammation, characterized by decreased expression of CCL2, COX-2, IL-8, and RAGE. Changes in CCL2, IL-8, and RAGE were intercorrelated and all correlated positively with changes in MLXIP, MAFF, MAFG, NCF1, and FTH1, and negatively with changes in HMOX1 and TKT; changes in IL-8 also correlated positively with change in COX-2. Total urinary excretion of tRES and HESP metabolites were strongly correlated. These findings suggest tRES-HESP counters MG accumulation and protein glycation, decreasing activation of the unfolded protein response and expression of TXNIP and TNFα, producing reversal of insulin resistance. tRES-HESP is suitable for further evaluation for treatment of insulin resistance and related disorders.

The genotoxic effects in the leukocytes of workers handling nanocomposite materials

The extensive development of nanotechnologies and nanomaterials poses a number of questions to toxicologists about the potential health risks of exposure to nanoparticles (NP). In this study, we analysed DNA damage in the leukocytes of 20 workers who were long-term exposed (18 ± 10 years) to NP in their working environment. Blood samples were collected in September 2016, before and after a shift, to assess (i) the chronic effects of NP on DNA (pre-shift samples) and (ii) the acute effects of exposure during the shift (the difference between pre- and post-shift samples). The samples from matched controls were taken in parallel with workers before the shift. Leukocytes were isolated from heparinised blood on a Ficoll gradient. The enzyme-modified comet assay (DNA formamido-pyrimidine-glycosylase and endonuclease III) demonstrated a considerable increase of both single- and double-strand breaks in DNA (DNA-SB) and oxidised bases when compared with the controls (2.4× and 2×, respectively). Acute exposure induced a further increase of DNA-SB. The welding and smelting of nanocomposites represented a higher genotoxic risk than milling and grinding of nanocomposite surfaces. Obesity appeared to be a factor contributing to an increased risk of oxidative damage to DNA. The data also indicated a higher susceptibility of males vs. females to NP exposure. The study was repeated in September 2017. The results exhibited similar trend, but the levels of DNA damage in the exposed subjects were lower compared to previous year. This was probably associated with lower exposure to NP in consequence of changes in nanomaterial composition and working operations. The further study involving also monitoring of personal exposures to NP is necessary to identify (i) the main aerosol components responsible for genotoxic effects in workers handling nanocomposites and (ii) the primary cause of gender differences in response to NP action.

Correlation between obesity, gestational diabetes mellitus, and pregnancy outcomes: an overview

Obesity has been identified mainly as a raise in the body's adiposity leading to prolonged overshoot of caloric intake over expenditure. Obesity has significant health-altering implications which have been shown to be implicated in the pathogenesis and progression of other diseases through its extensive physiological assaults. The prevalence of overweight and obesity has been an increasing epidemic worldwide. The number of obese births was even on the increase, with an increasing number of women of reproductive age registering as obese. Obesity is related to adverse perinatal outcomes and increased morbidity and mortality in pregnant women. The potential risk for multiple antenatal, postpartum, intrapartum, and neonatal complications is maternal obesity. Greater risk of developing Gestational Diabetes Mellitus (GDM), pregnancy induced hypertension (PIH), pre-eclampsia, risk of venous embolism, increased need for labor induction, and cesarean sections in the mother have been recorded in a comprehensive analysis of pregnancy complications associated with obesity. The link between obesity, gestational diabetes, and pregnancy outcomes will be briefly shown in this article.

Determinants of Resting Oxidative Stress in Middle-Aged and Elderly Men and Women: WASEDA'S Health Study

Previous studies have not investigated the determinants of resting oxidative stress, including physical fitness, as it relates to redox regulation. The present study therefore was aimed at identifying lifestyle and biological factors that determine resting oxidative stress, including objectively measured physical fitness. In 873 middle-aged and elderly men and women, age and anthropometric parameters, lifestyle-related parameters, medication and supplementation status, physical fitness, biochemical parameters, and nutritional intake status, as well as three plasma oxidative stress markers: protein carbonyl (PC), F₂-isoprostane (F₂-IsoP), and thiobarbituric acid reactive substances (TBARS), were surveyed and measured. The determinants of PC, F₂-IsoP, and TBARS in all participants were investigated using stepwise multiple regression analysis. In PC, age (β = −0.11, P = 0.002), leg extension power (β = −0.12, P = 0.008), BMI (β = 0.12, P = 0.004), and HDL-C (β = 0.08, P = 0.040) were included in the regression model (adjusted R² = 0.018). In the F₂-IsoP, smoking status (β = 0.07, P = 0.060), BMI (β = 0.07, P = 0.054), and HbA1c (β = −0.06, P = 0.089) were included in the regression model (adjusted R² = 0.006). In TBARS, glucose (β = 0.18, P < 0.001), CRF (β = 0.16, P < 0.001), age (β = 0.15, P < 0.001), TG (β = 0.11, P = 0.001), antioxidant supplementation (β = 0.10, P = 0.002), and HbA1c (β = −0.13, P = 0.004) were included in the regression model (adjusted R² = 0.071). In conclusion, the present study showed that age, anthropometric index, lifestyle-related parameters, medication and supplementation status, objectively measured physical fitness, biochemical parameters, and nutritional intake status explain less than 10% of oxidative stress at rest.

High day-to-day and diurnal variability of oxidative stress and inflammation biomarkers in people with type 2 diabetes mellitus and healthy individuals

Objective: Assess the variability and differences in oxidative stress, antioxidant, and inflammatory biomarkers in people with type 2 diabetes mellitus (T2D) and healthy controls.

Methods: Ten men and women diagnosed with T2D and ten healthy matched controls (CON) were recruited. Participants had venous blood taken at six different time points on different days, three in the morning (after overnight fast) and three in the afternoon. Inflammation (IL-6, 8, 10 and TNF-α), oxidative stress/antioxidant biomarkers (F₂-isoprostanes, protein carbonyls, total antioxidant capacity (TAC), glutathione peroxidase activity, IL-6, 8 & 10 and TNF-α) were assessed.

Results: Biomarker concentrations were similar between groups. There was large variability in nearly all biomarkers for both groups. For inflammatory measures, intra-individual coefficients of variation (CV) ranged from 64.0–92.1% and 100.9–259.0% for inter-individual differences. CVs for oxidative stress markers were lower (7.4–31.2% for intra-individual and 8.6–43.0% for inter-individual). TAC had the lowest intra-individual CV – 7% for T2D and 8% for CON. Protein carbonyls were more variable in the afternoon (34% CV) compared to morning (24% CV) in CON. IL-6 intra-individual CV was different between groups for afternoon measurements (93% T2D, 60% CON).

Conclusion: Oxidative stress and inflammatory biomarkers show considerable variation in both T2D and healthy populations.

Trial registration:ClinicalTrials.gov identifier: NCT01206725.

Human Nonmercaptalbumin Is a New Biomarker of Motor Function

The ratio of human nonmercaptalbumin (HNA) and reduced albumin (HMA) may be a new marker for oxidative stress. Locomotive syndrome (LS) is reduced mobility due to impairment of locomotive organs. We investigated whether the HNA/HMA ratio could be a new biomarker of LS. This study included 306 subjects (mean age 64.24 ± 10.4 years) who underwent LS tests, grip strength, walking speed, and tests for HNA and HMA. Oxidative stress was measured by the ratio of HMA (f(HMA) = (HMA/(HMA + HNA) × 100)), and the subjects were divided into normal (N group; f[HMA] ≥ 70%) and low (L group; f[HMA] < 70%) groups. There were 124 non-elderly (<65 years) and 182 elderly subjects (≥65 years). There were no significant differences in LS, grip strength, and walking speed between the L and N groups in the non-elderly subjects. However, significant differences were found in the elderly subjects. In logistic regression analysis, there was an association between f(HMA) and the LS severity at older ages. LS in the elderly is associated with a decline in HMA and, thus, an increase in oxidative stress. Thus, f(HMA) is a new biomarker of LS.

Redox changes in obesity, metabolic syndrome, and diabetes

"Life is an instantaneous encounter of circulating matter and flowing energy" (Jean Giaja, Serbian physiologist), is one of the most elegant definitions not only of life but the relationship of redox biology and metabolism. Their evolutionary liaison has created inseparable yet dynamic homeostasis in health, which, when disrupted, leads to disease. This interconnection is even more pertinent today, in an era of increasing metabolic diseases of epidemic proportions such as obesity, metabolic syndrome, and diabetes. Despite great advances in understanding the molecular mechanisms of redox and metabolic regulation, we face significant challenges in preventing, diagnosing, and treating metabolic diseases. The etiological association and temporal overlap of these syndromes present significant challenges for the discrimination of appropriate clinical biomarkers for diagnosis, treatment, and outcome prediction. These multifactorial, multiorgan metabolic syndromes with complex etiopathogenic mechanisms are accompanied by disturbed redox equilibrium in target tissues and circulation. Free radicals and reactive species are considered both a causal factor and a consequence of disease status. Thus, determining the subtypes and levels of free radicals and reactive species, oxidatively damaged biomolecules (lipids, proteins, and nucleic acids) and antioxidant defense components as well as redox-sensitive transcription factors and fluxes of redox-dependent metabolic pathways will help define existing and establish novel redox biomarkers for stratifying metabolic diseases. This review aims to discuss diverse redox/metabolic aspects in obesity, metabolic syndrome, and diabetes, with the imperative to help establish a platform for emerging and future redox-metabolic biomarkers research in precision medicine. Future research warrants detailed investigations into the status of redox biomarkers in healthy subjects and patients, including the use of emerging 'omic' profiling technologies (e.g., redox proteomes, lipidomes, metabolomes, and transcriptomes), taking into account the influence of lifestyle (diet, physical activity, sleep, work patterns) as well as circadian ~24h fluctuations in circulatory factors and metabolites.

Redox-related biomarkers in human cardiovascular disease - classical footprints and beyond

Global epidemiological studies show that chronic non-communicable diseases such as atherosclerosis and metabolic disorders represent the leading cause of premature mortality and morbidity. Cardiovascular disease such as ischemic heart disease is a major contributor to the global burden of disease and the socioeconomic health costs. Clinical and epidemiological data show an association of typical oxidative stress markers such as lipid peroxidation products, 3-nitrotyrosine or oxidized DNA/RNA bases with all major cardiovascular diseases. This supports the concept that the formation of reactive oxygen and nitrogen species by various sources (NADPH oxidases, xanthine oxidase and mitochondrial respiratory chain) represents a hallmark of the leading cardiovascular comorbidities such as hyperlipidemia, hypertension and diabetes. These reactive oxygen and nitrogen species can lead to oxidative damage but also adverse redox signaling at the level of kinases, calcium handling, inflammation, epigenetic control, circadian clock and proteasomal system. The in vivo footprints of these adverse processes (redox biomarkers) are discussed in the present review with focus on their clinical relevance, whereas the details of their mechanisms of formation and technical aspects of their detection are only briefly mentioned. The major categories of redox biomarkers are summarized and explained on the basis of suitable examples. Also the potential prognostic value of redox biomarkers is critically discussed to understand what kind of information they can provide but also what they cannot achieve.

Four Weeks of Detraining Induced by COVID-19 Reverse Cardiac Improvements from Eight Weeks of Fitness-Dance Training in Older Adults with Mild Cognitive Impairment

Physical training is considered as a low-cost intervention to generate cardioprotective benefits and to promote physical and mental health, while reducing the severity of acute respiratory infection symptoms in older adults. However, lockdown measures during COVID-19 have limited people's opportunity to exercise regularly. The aim of this study was to investigate the effect of eight weeks of Fitness and Dance training, followed by four weeks of COVID-19-induced detraining, on cardiac adaptations and physical performance indicators in older adults with mild cognitive impairment (MCI). Twelve older adults (6 males and 6 females) with MCI (age, 73 ± 4.4 y; body mass, 75.3 ± 6.4 kg; height, 172 ± 8 cm; MMSE score: 24-27) participated in eight weeks of a combined Fitness-Dance training intervention (two sessions/week) followed by four weeks of training cessation induced by COVID-19 lockdowns. Wireless Polar Team Pro and Polar heart rate sensors (H10) were used to monitor covered distance, speed, heart rate (HR min, avg and max), time in HR zone 1 to 5, strenuousness (load score), beat-to-beat interval (max RR and avg RR) and heart rate variability (HRV-RMSSD). One-way ANOVA was used to analyze the data of the three test sessions (T1: first training session, T2: last training session of the eight-week training program, and T3: first training session after the four-week training cessation). Statistical analysis showed that eight weeks of combined Fitness-Dance training induced beneficial cardiac adaptations by decreasing HR (HR min, HR avg and HR max) with p < 0.001, ES = 0.5-0.6 and Δ = -7 to-9 bpm, and increasing HRV related responses (max and avg RR and RMSSD), with p < 0.01 and ES = 0.4. Consequently, participants spent more time in comfortable HR zones (e.g., p < 0.0005; ES = 0.7; Δ = 25% for HR zone 1) and showed reduced strenuousness (p = 0.02, Δ = -15% for load score), despite the higher covered total distance and average speed (p < 0.01; ES = 0.4). However, these changes were reversed after only four weeks of COVID-19 induced detraining, with values of all parameters returning to their baseline levels. In conclusion, eight weeks of combined Fitness-Dance training seems to be an efficient strategy to promote cardioprotective benefits in older adults with MCI. Importantly, to maintain these health benefits, training has to be continued and detraining periods should be reduced. During a pandemic, home-based exercise programs may provide an effective and efficient alternative of physical training.

Biomarkers representing key aging-related biological pathways are associated with subclinical atherosclerosis and all-cause mortality: The Framingham Study

BACKGROUND

Increased oxidative stress, leukocyte telomere length (LTL) shortening, endothelial dysfunction, and lower insulin-like growth factor (IGF)-1 concentrations reflect key molecular mechanisms of aging. We hypothesized that biomarkers representing these pathways are associated with measures of subclinical atherosclerosis and all-cause mortality.

METHODS AND RESULTS

We evaluated up to 2,314 Framingham Offspring Study participants (mean age 61 years, 55% women) with available biomarkers of aging: LTL, circulating concentrations of IGF-1, asymmetrical dimethylarginine (ADMA), and urinary F2-Isoprostanes indexed to urinary creatinine. We evaluated the association of each biomarker with coronary artery calcium [ln (CAC+1)] and carotid intima-media thickness (IMT). In multivariable-adjusted linear regression models, higher ADMA levels were associated with higher CAC values (βADMA per 1-SD increase 0.25; 95% confidence interval [CI] [0.11, 0.39]). Additionally, shorter LTL and lower IGF-1 values were associated with higher IMT values (βLTL -0.08, 95%CI -0.14, -0.02, and βIGF-1 -0.04, 95%CI -0.08, -0.01, respectively). During a median follow-up of 15.5 years, 593 subjects died. In multivariable-adjusted Cox regression models, LTL and IGF-1 values were inversely associated with all-cause mortality (hazard ratios [HR] per SD increase in biomarker, 0.85, 95% CI 0.74-0.99, and 0.90, 95% CI 0.82-0.98 for LTL and IGF-1, respectively). F2-Isoprostanes and ADMA values were positively associated with all-cause mortality (HR per SD increase in biomarker, 1.15, 95% CI, 1.10-1.22, and 1.10, 95% CI, 1.02-1.20, respectively).

CONCLUSION

In our prospective community-based study, aging-related biomarkers were associated with measures of subclinical atherosclerosis cross-sectionally and with all-cause mortality prospectively, supporting the concept that these biomarkers may reflect the aging process in community-dwelling adults.

Selection and Characterization of Probiotic Bacteria Exhibiting Antiadipogenic Potential in 3T3-L1 Preadipocytes

Abnormal adipocyte growth, distinguished by an increase in cell numbers and cellular differentiation, is regarded as a major pathological characteristic of obesity. Thus, inhibition of adipogenic differentiation in adipocytes could prevent obesity. Recently, certain probiotic stains have been reported to regulate lipid metabolism in vitro and/or in vivo. In this backdrop, this study aimed to investigate basic probiotic properties and potential antiobesity characteristics of mouse 3T3-L1 preadipocytes. Six lactic acid bacteria (LAB) strains were prescreened for their cholesterol-lowering activity, antioxidant activity, and survival at low pH and in a solution containing bile salts. These six strains were investigated for antiadipogenic activity by employing 3T3-L1 mouse preadipocytes. 3T3-L1 cells were treated with selected strains during the differentiation process. Lactobacillus johnsonii 3121 and Lactobacillus rhamnosus 86 were found to be more capable of reducing triglyceride and lipid accumulation, as compared to control group, which are fully differentiated 3T3-L1 adipocytes. These strains also inhibited adipocyte differentiation by downregulating the adipogenic transcription factor in 3T3-L1 adipocytes. Taken together, these results indicate that L. johnsonni 3121 and L. rhamnosus 86 could potentially act as probiotic bacteria and prevent fat accumulation by regulating adipogenesis-related markers.

Iron Deficiency in Obesity and after Bariatric Surgery

Iron deficiency (ID) is particularly frequent in obese patients due to increased circulating levels of acute-phase reactant hepcidin and adiposity-associated inflammation. Inflammation in obese subjects is closely related to ID. It induces reduced iron absorption correlated to the inhibition of duodenal ferroportin expression, parallel to the increased concentrations of hepcidin. Obese subjects often get decreased inflammatory response after bariatric surgery, accompanied by decreased serum hepcidin and therefore improved iron absorption. Bariatric surgery can induce the mitigation or resolution of obesity-associated complications, such as hypertension, insulin resistance, diabetes mellitus, and hyperlipidemia, adjusting many parameters in the metabolism. However, gastric bypass surgery and sleeve gastrectomy can induce malabsorption and may accentuate ID. The present review explores the burden and characteristics of ID and anemia in obese patients after bariatric surgery, accounting for gastric bypass technique (Roux-en-Y gastric bypass-RYGB) and sleeve gastrectomy (SG). After bariatric surgery, obese subjects' iron status should be monitored, and they should be motivated to use adequate and recommended iron supplementation.

Contribution of Adipose Tissue Oxidative Stress to Obesity-Associated Diabetes Risk and Ethnic Differences: Focus on Women of African Ancestry

Adipose tissue (AT) storage capacity is central in the maintenance of whole-body homeostasis, especially in obesity states. However, sustained nutrients overflow may dysregulate this function resulting in adipocytes hypertrophy, AT hypoxia, inflammation and oxidative stress. Systemic inflammation may also contribute to the disruption of AT redox equilibrium. AT and systemic oxidative stress have been involved in the development of obesity-associated insulin resistance (IR) and type 2 diabetes (T2D) through several mechanisms. Interestingly, fat accumulation, body fat distribution and the degree of how adiposity translates into cardio-metabolic diseases differ between ethnicities. Populations of African ancestry have a higher prevalence of obesity and higher T2D risk than populations of European ancestry, mainly driven by higher rates among African women. Considering the reported ethnic-specific differences in AT distribution and function and higher levels of systemic oxidative stress markers, oxidative stress is a potential contributor to the higher susceptibility for metabolic diseases in African women. This review summarizes existing evidence supporting this hypothesis while acknowledging a lack of data on AT oxidative stress in relation to IR in Africans, and the potential influence of other ethnicity-related modulators (e.g., genetic-environment interplay, socioeconomic factors) for consideration in future studies with different ethnicities.

From carotenoid intake to carotenoid blood and tissue concentrations - implications for dietary intake recommendations

There is uncertainty regarding carotenoid intake recommendations, because positive and negative health effects have been found or are correlated with carotenoid intake and tissue levels (including blood, adipose tissue, and the macula), depending on the type of study (epidemiological vs intervention), the dose (physiological vs supraphysiological) and the matrix (foods vs supplements, isolated or used in combination). All these factors, combined with interindividual response variations (eg, depending on age, sex, disease state, genetic makeup), make the relationship between carotenoid intake and their blood/tissue concentrations often unclear and highly variable. Although blood total carotenoid concentrations <1000 nmol/L have been related to increased chronic disease risk, no dietary reference intakes (DRIs) exist. Although high total plasma/serum carotenoid concentrations of up to 7500 nmol/L are achievable after supplementation, a plateauing effect for higher doses and prolonged intake is apparent. In this review and position paper, the current knowledge on carotenoids in serum/plasma and tissues and their relationship to dietary intake and health status is summarized with the aim of proposing suggestions for a "normal," safe, and desirable range of concentrations that presumably are beneficial for health. Existing recommendations are likewise evaluated and practical dietary suggestions are included.

Proportions of long-chain ω-3 fatty acids in erythrocyte membranes of Canadian adults: Results from the Canadian Health Measures Survey 2012-2015

BACKGROUND

The Omega-3 Index (OI) is a proposed marker of coronary artery disease (CAD) risk. Another index, the EPA/arachidonic acid (AA) ratio has also been proposed as a possible risk marker for CAD.

OBJECTIVE

Our primary objective was to characterize the Canadian population subgroups that have an undesirable OI (<4%, associated with high CAD risk) and to identify the participants' characteristics most strongly associated with the OI. Our secondary objective was to identify the characteristics most strongly associated with the EPA/AA ratio.

DESIGN

Data from 4025 adult participants of cycles 3 and 4 (2012-2015) of the cross-sectional Canadian Health Measures Survey were pooled. Adjusted mean proportions of erythrocyte membrane ω-3 (n-3) fatty acids, total ω-6 fatty acids, and ratios were analyzed by sociodemographic, health, and lifestyle characteristics using covariate-adjusted models.

RESULTS

The mean OI was 4.5%. Almost 40% of Canadians had an undesirable (<4%) OI. ω-3 supplement use, fish intake, and race were the variables most strongly associated with OI scores. The prevalence of undesirable OI was significantly higher among participants consuming fish less than twice a week (43.8%; 95% CI: 39.0%, 48.6%) than among those consuming more fish (12.7%; 95% CI: 7.8%, 19.9%), among smokers (62.7%; 95% CI: 52.9%, 71.7%) than nonsmokers (33.4%; 95% CI: 29.4%, 37.7%), in whites (42.7%; 95% CI: 38.2%, 47.4%) than in Asians (23.0%; 95% CI: 15.4%, 33.0%), and in adults aged 20-39 y (49.6%; 95% CI: 42.3%, 56.9%) than in those aged 60-79 y (24.4%; 95% CI: 21.0%, 28.1%). ω-3 supplement intake and fish intake were the characteristics most strongly associated with EPA/AA. All P ≤ 0.05.

CONCLUSIONS

An important proportion of Canadian adults has an undesirable (<4%) OI, with higher prevalence in some subgroups. Further assessment is required to determine the value and feasibility of an increase in the population's OI to the currently proposed target of ≥8% as a potential public health objective.

Superoxide Dismutase Administration: A Review of Proposed Human Uses

Superoxide dismutases (SODs) are metalloenzymes that play a major role in antioxidant defense against oxidative stress in the body. SOD supplementation may therefore trigger the endogenous antioxidant machinery for the neutralization of free-radical excess and be used in a variety of pathological settings. This paper aimed to provide an extensive review of the possible uses of SODs in a range of pathological settings, as well as describe the current pitfalls and the delivery strategies that are in development to solve bioavailability issues. We carried out a PubMed query, using the keywords "SOD", "SOD mimetics", "SOD supplementation", which included papers published in the English language, between 2012 and 2020, on the potential therapeutic applications of SODs, including detoxification strategies. As highlighted in this paper, it can be argued that the generic antioxidant effects of SODs are beneficial under all tested conditions, from ocular and cardiovascular diseases to neurodegenerative disorders and metabolic diseases, including diabetes and its complications and obesity. However, it must be underlined that clinical evidence for its efficacy is limited and consequently, this efficacy is currently far from being demonstrated.

Association of fine particulate matter with glucose and lipid metabolism: a longitudinal study in young adults

OBJECTIVES

This study aimed to evaluate whether PM2.5 exposure in a highly polluted area (>100 µg/m3) affects glucose and lipid metabolism in healthy adults.

METHODS

We recruited 110 healthy adults in Baoding city, Hebei, China, and followed them up between 2017 and 2018. Personal air samplers were used to monitor personal PM2.5 levels. Eight glucose and lipid metabolism parameters were quantified. We performed the linear mixed-effect models to investigate the relationships between PM2.5 and glucose and lipid metabolism parameters. Stratified analyses were further performed according to sex and body mass index (BMI).

RESULTS

The concentration of PM2.5 was the highest in spring, with a median of 232 μg/m3 and the lowest in autumn (139 μg/m3). After adjusting for potential confounders, we found that for each twofold increase in PM2.5, the median of insulin concentration decreased by 5.89% (95% CI -10.91% to -0.58%; p<0.05), and ox-LDL increased by 6.43% (95% CI 2.21% to 10.82%; p<0.05). Stratified analyses indicated that the associations were more pronounced in females, overweight and obese participants.

CONCLUSIONS

Exposure to high PM2.5 may have deleterious effects on glucose and lipid metabolism. Females, overweight and obese participants are more vulnerable.

The Relationship between Oxidative Stress and Anxiety in a Healthy Older Population

Background/study context: F₂-Isoprostanes are putative markers of oxidative stress, one of the processes associated with biological senescence. Evidence exists for elevated F₂-Isoprostanes in chronic conditions including psychiatric disorders. Few studies have examined the relationship between oxidative stress and mood in older healthy samples, to establish the influence on mental health. Given current aging demographics in many nations, management of brain and mental health is crucial for longevity, chronic disease management, and quality of life.Method: We investigated the relationship between F₂-Isoprostanes, a marker for oxidative stress, and anxiety and mood in 262 healthy adults aged 60-75 years, using baseline data from the Australian Research Council Longevity Intervention (ARCLI; ANZCTR12611000487910), a 12-month nutraceutical intervention study.Results: Higher F2 levels significantly predicted increased Depression-dejection and Anger-hostility subscale scores from the Profile of Mood States (POMS). Fatigue-inertia subscale was predicted by increased Body Mass Index. Spielberger State-Trait Inventory (STAI) scores were significantly higher in females.Conclusion: While the primary outcome data did not find a definitive relationship between F2 and total mood or general anxiety levels, the sub-scale data adds weight toward growing literature that biological processes such as oxidative stress are in part related to mood. This is a modifiable risk factor contributing to physical and mental wellbeing that are crucial to healthy aging.

Oxidative Stress Is Increased in Combined Oral Contraceptives Users and Is Positively Associated with High-Sensitivity C-Reactive Protein

Information concerning the mechanisms underlying oxidative stress and low-grade inflammation in young healthy women predisposing eventually to future diseases is scarce. We investigated the relationship of oxidative stress and high-sensitivity C-reactive protein (hsCRP) in fertile-age women by oral combined contraceptive (OC) use. Caucasian Italian healthy non-obese women (n = 290; 100 OC-users; 190 non-OC-users; mean age 23.2 ± 4.7 years) were analyzed. Blood hydroperoxides, as oxidative stress biomarkers, were assessed by Free Oxygen Radical Test (FORT). Serum hsCRP was determined by an ultra-sensitive method (hsCRP). Markedly elevated oxidative stress (≥400 FORT Units) was found in 77.0% of OC-users and 1.6% of non-OC-users, odds ratio (OR) = 209, 95% CI = 60.9–715.4, p < 0.001. Elevated hsCRP levels ≥ 2.0 mg/L, considered risky for cardiovascular diseases (CVDs), were found in 41.0% of OC-users and 9.5% of non-OC-users, OR = 6.6, 95%CI 3.5–12.4, p < 0.001. Hydroperoxides were strongly positively correlated to hsCRP in all women (r_s = 0.622, p < 0.001), in OC-users (r_s = 0.442, p < 0.001), and in non-OC-users (r_s = 0.426, p < 0.001). Women with hydroperoxides ≥ 400 FORT Units were eight times as likely to have hsCRP ≥ 2 mg/L. In non-OC-users only, hydroperoxides values were positively correlated with weight and body mass index, but negatively correlated with red meat, fish and chocolate consumption. Our research is the first finding a strong positive correlation of serum hydroperoxides with hsCRP, a marker of low-grade chronic inflammation, in young healthy women. Further research is needed to elucidate the potential role of these two biomarkers in OC-use associated side-effects, like thromboembolism and other CVDs.

Blood pro-oxidant/antioxidant balance in young men with class II obesity after 20 sessions of whole body cryostimulation: a preliminary study

Objectives: In obesity, there is a shift in the pro-oxidative-antioxidant balance towards the oxidationreactions. However, it has been shown that in people with normal body composition, after a series of whole-body cryotherapy (WBC), the balance shifts in the opposite direction.

Design: The aim of the study was to assess the impact of 20 WBC treatments on blood pro-oxidative-antioxidant balance.

Interventions: Study included 14 obese (BMI > 35) and 10 non-obese volunteers.

Methods: The total antioxidative (TAS/TAC) and pro-oxidative status (TOS/TOC) in serum and activity of antioxidant enzymes in erythrocytes were determined before the first and 2 hours after the last cryostimulation.

Results: In the obese group, a significantly higher level of TOS/TOC, and its significant decrease after the WBC series, was observed. Cryotherapy had no influence on TAS/TAC level which was similar in both groups. Changes in activity of antioxidant enzymes were multidirectional. An increase in CAT activity in the obese group was observed. OSI, both before and after a series of treatments, was significantly higher in obese subjects.

Conclusions: A beneficial effect on the level of TOS/TOC and CAT activity was indicated, but the proposed number of treatments for patients with class II obesity turned out to be insufficient.

Trial registration:Australian New Zealand Clinical Trials Registry identifier: ACTRN12619000524190.

Serum vitamin E level and gestational diabetes mellitus: a systematic review and meta-analysis

Purpose

Gestational diabetes mellitus (GDM) is one of the most common medical complications in pregnancy. This systematic review aimed to evaluate the association between vitamin E and GDM.

Methods

Relevant articles from the Cochrane Library, PubMed, Scopus, Science Direct, Web of Science, and EMBASE databases up to December 2019 were searched. The inclusion criteria were observational full-text articles. The fixed and random effect models were used to analyze the pooled data using Review Manager 5.3.

Results

Thirteen studies, including 596 participants, of whom 285 were diagnosed with GDM were included in the meta-analysis. The vitamin E level was significantly lower in women with GDM (MD: - 0.10; 95% CI: [-0.15, - 0.05]). The level of vitamin E was not different between overweight women with GDM and healthy pregnant women (MD: 0.03; 95% CI: [-0.08, 0.013]). The level of vitamin E was significantly lower in the third trimester of pregnancy in GDM women in comparison to the healthy pregnant women(MD: -0.09; 95% CI: [-0.12, -0.06]).

Conclusion

This study showed that the level of vitamin E is significantly lower in GDM women compared to healthy pregnant women.

Effects of a Single Oral Megadose of Vitamin D3 on Inflammation and Oxidative Stress Markers in Overweight and Obese Women: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

AIM

The study aimed to evaluate the effects of vitamin D3 (VD3) supplementation on inflammation and oxidative stress markers in overweight and obese women with deficiency or insufficiency of vitamin D.

METHODS

Twenty-nine overweight or obese women who had a deficiency or insufficiency of vitamin D were placed into two groups according to VD3 intervention. Patients in the supplemented group received a single oral megadose of VD3 (VD3, n=14). Patients in placebo group received a single oral identical capsule without vitamin D (placebo, n = 15). Anthropometric and biochemical variables were assessed at baseline and after 4-weeks intervention.

RESULTS

Anthropometric variables (waist circumference, waist-hip ratio, waist-height ratio and body mass index) were similar between groups (p > 0.05). VD3 supplementation increased the serum levels of 25-hydroxyvitamin D (p=0.000), malondialdehyde (p=0.021) and C-reactive protein (p=0.043) in overweight and obese women. Additionally, VD3 supplementation reduced the serum levels of aspartate aminotransferase (AST, p=0.035), alanine aminotransferase (ALT, p<0.0001) in overweight and obese women. Despite this, the serum levels of parathyroid hormone (PTH), fasting glucose (FG), and alpha-1- acid glycoprotein (A1GPA), total antioxidant capacity (TAC) were similar between groups.

CONCLUSION

In summary, a single oral megadose of VD3 increased 25-hydroxyvitamin D serum levels but did not improve oxidative stress and inflammation markers.

The association between dietary antioxidant quality score with metabolic syndrome and its components in Iranian adults: A cross-sectional study

We aimed to investigate whether adherence to dietary antioxidant quality score (DAQS) is associated with metabolic syndrome (MetS) among the Tehranian population. This cross-sectional study was conducted on 270 apparently healthy adults aged between 18 and 45 years old who lived in Tehran, Iran, between February 2017 and December 2018. Participants were categorized based on tertile cut-off points of DAQs. To examine the association between DAQS and MetS and its components, we used multivariable logistic regression analysis in different models. Adherence to DAQS was associated with a significant increase for intake of vitamin B6 (P-value = 0.02), riboflavin (P-value < 0.001), folate (P-value = 0.03), selenium (P-value = 0.03), vitamin D (P-value < 0.001), and calcium (P-value < 0.001). Adherence to DAQS showed a significant decrease for odds of systolic blood pressure (SBP) (OR: 0.17, 95% CI: 0.04, 0.65, P-value = 0.03). We also found that the overall adherence to DAQS was not significantly related to MetS and its other components. In conclusion, although we observed an improvement in SBP with a greater adherence to dietary antioxidant quality score, there was no association between DAQS and metabolic syndrome and its other components.

Targeting Autophagy to Counteract Obesity-Associated Oxidative Stress

Reactive oxygen species (ROS) operate as key regulators of cellular homeostasis within a physiological range of concentrations, yet they turn into cytotoxic entities when their levels exceed a threshold limit. Accordingly, ROS are an important etiological cue for obesity, which in turn represents a major risk factor for multiple diseases, including diabetes, cardiovascular disorders, non-alcoholic fatty liver disease, and cancer. Therefore, the implementation of novel therapeutic strategies to improve the obese phenotype by targeting oxidative stress is of great interest for the scientific community. To this end, it is of high importance to shed light on the mechanisms through which cells curtail ROS production or limit their toxic effects, in order to harness them in anti-obesity therapy. In this review, we specifically discuss the role of autophagy in redox biology, focusing on its implication in the pathogenesis of obesity. Because autophagy is specifically triggered in response to redox imbalance as a quintessential cytoprotective mechanism, maneuvers based on the activation of autophagy hold promises of efficacy for the prevention and treatment of obesity and obesity-related morbidities.

Health examination results and work environment factors affecting urinary 8-hydroxy-2'-deoxyguanosine levels

OBJECTIVE

Oxidative stress is considered to cause lifestyle-related diseases, including cancer. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) is widely analyzed as an oxidative stress marker. We extensively scrutinized the relationships between 8-OHdG levels and lifestyle choices as carcinogenic factors.

METHODS

In this study, we investigated health examination results and working conditions affecting urinary 8-OHdG levels in 503 male workers.

RESULTS

The urinary 8-OHdG level was positively associated with high blood sugar and leanness in smokers. In addition, urinary 8-OHdG tended to increase with organic solvent or hydrochloric acid exposure, as well as long working hours. On the other hand, the urinary 8-OHdG level was negatively associated with high plasma LDL-cholesterol levels in non-smokers and anemia.

CONCLUSION

According to the results, anemia decreased the oxidative stress, regardless of smoking status, while leanness or high blood sugar increased the oxidative stress in smokers, and the presence of plasma cholesterol contributed to the lower oxidative stress in non-smokers. Certain types of occupational exposure may cause oxidative stress. The measurement of urinary 8-OHdG at annual health checks may be a useful biomarker for preventing lifestyle- and work-related diseases.

The Associations of Perceived and Oxidative Stress with Hypertension in a Cohort of Police Officers

PURPOSE

Associations between perceived stress and oxidative stress marker and metabolic syndrome (MetS) components were investigated in a cohort of police officers.

METHODS

Cross-sectional data from a cohort of non-diabetic subjects (n=233; 19F), median [interquartile range] age 50 [37-44] years, were analysed. MetS was construed in line with International Diabetes Federation (IDF) criteria and perceived stress with Cohen's 10-item Perceived Stress Scale. Plasma oxidative stress marker (free 8-iso-prostaglandin F_2α; 8-iso-PGF_2α), presence of coronary plaque, carotid artery intima-media thickness (cIMT), and physical activity level were also determined.

RESULTS

Obesity was established in 100 (42.92%), hypertension in 111 (47.64), whereas MetS was identified in 104 (44.63%) of the study subjects. A significant difference (p=0.003) in plasma 8-iso-PGF_2α level, depending on the MetS components status, was noted. The associations of perceived stress with plasma 8-iso-PGF_2α level and the select study variables were gender-specific. In multivariate analysis (adjusted for age and current smoking), positive associations of plasma 8-iso-PGF_2α levels with PSS score (B=0.108, 95% CI [0.008, 0.209], p=0.03) and systolic blood pressure (B=0.029, 95% CI [0.003, 0.057], p=0.02) in men only were established. Both the perceived stress (OR 1.101, 95% CI [1.001-1.202], p=0.03) and plasma 8-iso-PGF_2α levels (OR 1.223, 95% CI [1.046-1.432], p=0.01) impacted the prevalence of hypertension. Out of the MetS components, the effect of waist circumference (OR=1.138, 95% CI [1.064-1.218], p=0.0001) and glucose (B=2.696, 95% CI [1.081-6.725], p=0.03) were also encountered. No such associations were noted in women, though, neither in univariate nor in multivariate analyses. The prevalence of coronary plaque (0.001), obesity (p<0.001), hypertension (p<0.001) and median cIMT value (p=0.005), as well as leisure-time (p=0.04) and total walking physical activity (p=0.03), differed significantly between the subgroups stratified by MetS components status.

CONCLUSION

Both the perceived and oxidative stress were found instrumental in promoting hypertension in a cohort of police officers under study, whereas all study outcomes were conclusively gender-related.

Indoor Air Pollution and Respiratory Health

Worldwide, more than 4 million deaths annually are attributed to indoor air pollution. This largely preventable exposure represents a key target for reducing morbidity and mortality worldwide. Significant respiratory health effects are observed, ranging from attenuated lung growth and development in childhood to accelerated lung function decline and is determined by chronic obstructive pulmonary disease later in life. Personal exposure to household air pollutants include household characteristics, combustion of solid fuels, cooking practices, and household pest allergens. This review outlines important sources of indoor air pollution, their respiratory health effects, and strategies to reduce household pollution and improve lung health across the globe.

Emerging roles for non-selenium containing ER-resident glutathione peroxidases in cell signaling and disease

Maintenance of cellular redox control is pivotal for normal cellular functions and cell fate decisions including cell death. Among the key cellular redox systems in mammals, the glutathione peroxidase (GPX) family of proteins is the largest conferring multifaceted functions and affecting virtually all cellular processes. The endoplasmic reticulum (ER)-resident GPXs, designated as GPX7 and GPX8, are the most recently added members of this family of enzymes. Recent studies have provided exciting insights how both enzymes support critical processes of the ER including oxidative protein folding, maintenance of ER redox control by eliminating H₂O₂, and preventing palmitic acid-induced lipotoxicity. Consequently, numerous pathological conditions, such as neurodegeneration, cancer and metabolic diseases have been linked with altered GPX7 and GPX8 expression. Studies in mice have demonstrated that loss of GPX7 leads to increased differentiation of preadipocytes, increased tumorigenesis and shortened lifespan. By contrast, GPX8 deficiency in mice results in enhanced caspase-4/11 activation and increased endotoxic shock in colitis model. With the increasing recognition that both types of enzymes are dysregulated in various tumor entities in man, we deem a review of the emerging roles played by GPX7 and GPX8 in health and disease development timely and appropriate.

Total Antioxidant Status in Stable Chronic Obstructive Pulmonary Disease

Objective

This study evaluates the total antioxidant status (TAS) in plasma of stable chronic obstructive pulmonary disease (COPD) patients. Earlier studies of their relationship showed inconsistent findings.

Patients and Methods

We compared TAS between 90 COPD patients and 30 age- and sex-matched controls (mean age 67 ± 7.9, 87 males and 33 females) according to airway obstruction severity, gender, smoking status (current/ former/ non-smoker), smoking-dose, the number of exacerbations in the previous year, nutritional status and hypercapnia.

Results

There were no differences in pack-years between COPD and controls, neither in COPD groups. The median time from the last exacerbation was 5 months (interquartile range 3-8.3). TAS was significant higher in COPD than controls (1.68 [1.55-1.80] versus 1.59 [1.54-1.68], respectively; P = 0.03). TAS was significantly higher in COPD men than women (1.7 [1.6-1.8] versus 1.57 [1.5-1.7], respectively; P = 0.001). In COPD groups, there were no significant differences between the severity of airway obstruction and TAS. We found significant positive correlation between pack-years and TAS in all participants (Rho = 0.429, P = 0.004) and COPD patients (Rho = 0.359, P = 0.02), but not in controls. TAS was a significant predictor of COPD (β = 3.26; P = 0.04; OR = 26.01; 95% CI: 1.20 to 570.8). We failed to find significant differences between TAS and smoking status, frequency of exacerbations in the previous year, nutritional status and hypercapnia.

Conclusion

TAS was a significant predictor of COPD. TAS was a significantly higher in stable COPD than controls, higher in COPD men than women, but there was no significant correlation between TAS and the airway obstruction severity. Our results suggest that it could be appropriate to include the time from the last exacerbation in the oxidant-antioxidant balance analysis of COPD patients.

Smoking and Endothelial Dysfunction

Cigarette smoking is one of the most important health concerns worldwide. Even though the rate of smoking is declining in developed countries, it is still experiencing growth in developing regions. Many studies have examined the relationship between smoking, as an established risk factor, and cardiovascular diseases. We provide an updated review of the underlying mechanisms of smokinginduced cardiovascular diseases, with a focus on the relationship between smoking and oxidative stress, particularly from the perspective of endothelial cell dysfunction. We review smoking-induced oxidative stress as a trigger for a generalized vascular inflammation associated with cytokine release, adhesion of inflammatory cells and, ultimately, disruption of endothelial integrity as a protective barrier layer. We also briefly discuss the harms related to the vaping of electronic cigarettes, which many erroneously consider as a safe alternative to smoking. We conclude that even though e-cigarette could be a helpful device during the transition period of cigarette quitting, it is by no means a safe substitute.

Huoxue Huatan Decoction Ameliorates Myocardial Ischemia/Reperfusion Injury in Hyperlipidemic Rats via PGC-1α-PPARα and PGC-1α-NRF1-mtTFA Pathways

Objective

The aim of this study was to eluc\idate the preventive and therapeutic effects and the underlying mechanisms of Huoxue Huatan Decoction (HXHT) on myocardial ischemia/reperfusion (I/R) injury in hyperlipidemic rats.

Methods

An I/R model was established in hyperlipidemic Wistar rats. After 4–8 weeks of HXHT treatment, the physical signs of rats were observed. Lipid metabolism, myocardial enzyme spectrum, cardiac function, myocardial histomorphology, and mitochondrial biosynthesis were investigated by a biochemical method, ultrasonography, electron microscopy, pathological examination, real-time PCR, and Western blot.

Results

HXHT can affect lipid metabolism at different time points and significantly reduce the levels of cholesterol (CHO), triglyceride (TG), high-density lipid-cholesterol (HDL-C), and low-density lipid-cholesterol (LDL-C) in hyperlipidemic rats (P < 0.05 or P < 0.01); it can significantly reduce the levels of creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH), reduce the myocardial infarct size and myocardial ischemic area, and improve cardiac function. The results of myocardial histomorphology showed that HXHT could protect myocardial cells, relieve swelling, reduce the number of cardiac lipid droplets, and improve myocardial mitochondrial function. HXHT could significantly increase the levels of total superoxide dismutase (T-SOD) and succinate dehydrogenase (SDH) (P < 0.05 or P < 0.01), increase CuZn-superoxide dismutase (CuZn-SOD) and glutathione-peroxidase (GSH-Px) levels, and decrease the levels of malondialdehyde (MDA) (P < 0.05); it could increase the mRNA and protein expression levels of peroxisome proliferator-activated receptor-gamma coactivator 1 alpha (PGC-1α), peroxisome proliferator-activated receptor alpha (PPARα), nuclear respiratory factor 1 (NRF1), and mitochondrial transcription factor A (mtTFA) (P < 0.05 or P < 0.01), and increase the synthesis of mitochondrial DNA (mtDNA) (P < 0.01).

Conclusion

HXHT can reduce myocardial I/R injury in hyperlipidemic rats. The protective mechanisms may involve a reduction in blood lipids, enhancement of PGC-1α–PPARα pathway activity, and, subsequently, an increase in fatty acid β-oxidation, which may provide the required input for mitochondrial energy metabolism. HXHT can additionally enhance PGC-1α–NRF1–mtTFA pathway activity and, subsequently, increase the antioxidant capacity, promote mtDNA synthesis, and reduce mitochondrial damage. The two pathways use PGC-1α as the intersection point to protect mitochondrial structure and function, reduce I/R-induced injury, and improve cardiac function.

8-Isoprostane: A salivary oxidative stress biomarker for oral submucous fibrosis and oral squamous cell carcinoma

Background

8-isoprostane is one of the stable oxidative stress marker formed by the lipid peroxidation of arachidonic acid. It is present in detectable quantities in all biological fluids. Elevation of 8-Isoprostane has been reported in various neurological, cardiological disorders, and periodontal diseases.

Aim

The present study was conducted to estimate and compare the level of 8-isoprostane in plasma and saliva in patients with oral squamous cell carcinoma (OSCC), oral submucous fibrosis (OSMF), and in controls. The study also aimed to find out if 8-isoprostane can be used as an effective oxidative stress marker in evaluating the disease progression in OSCC.

Materials and Methods

Plasma and salivary samples were taken from 10 cases each of clinically diagnosed OSMF, clinically and hisotpathologically diagnosed cases of OSCC and controls. The samples were subjected to 8-Isoprostane ELISA procedure and analyzed. Statistical analysis was performed using the SPSS software.

Results

The levels of 8-isoprostane in plasma showed an average increase from normal to OSMF to OSCC but was not statistically significant. The variations in the level of salivary 8-isoprostane were found to be statistically significant (P = 0.037) suggesting that there is a gradual increase in levels of isoprostane from controls to OSMF to OSCC.

Conclusion

The results showed that the concentration of isoprostane in saliva showed a progressive and steady increase from control through OSMF to OSCC indicating that saliva could be used as an effective diagnostic tool in estimating tumor markers. Large scale studies correlating with other potentially malignant oral disorders are required to ascertain the role of 8-Isoprostane as an ideal tumor marker.

Selenium and RNA Virus Interactions: Potential Implications for SARS-CoV-2 Infection (COVID-19)

SARS-CoV-2 is an RNA virus responsible for the COVID-19 pandemic that already claimed more than 340,000 lives worldwide as of May 23, 2020, the majority of which are elderly. Selenium (Se), a natural trace element, has a key and complex role in the immune system. It is well-documented that Se deficiency is associated with higher susceptibility to RNA viral infections and more severe disease outcome. In this article, we firstly present evidence on how Se deficiency promotes mutations, replication and virulence of RNA viruses. Next, we review how Se might be beneficial via restoration of host antioxidant capacity, reduction of apoptosis and endothelial cell damages as well as platelet aggregation. It also appears that low Se status is a common finding in conditions considered at risk of severe COVID-19, especially in the elderly. Finally, we present a rationale for Se use at different stages of COVID-19. Se has been overlooked but may have a significant place in COVID-19 spectrum management, particularly in vulnerable elderly, and might represent a game changer in the global response to COVID-19.

Supplementation of Heliotropium indicum Linn attenuates obesity and associated metabolic disorders in high-carbohydrate-high-fat diet-induced obese rats

Heliotropium indicum Linn is a leafy vegetable that has been used in Bangladeshi ethnomedicinal practices. The attenuation effect of H. indicum supplementation was evaluated in high carbohydrate high-fat (HCHF) diet-induced obesity and associated disorders in 8-weeks-old female Wister rats. H. indicum significantly (p < .05) prevented weight gain and improved glucose intolerance in obese rats. It also significantly (p < .05) ameliorated lipid parameters in HCHF diet fed rats preventing hypercholesterolemia and hypertriglyceridemia, resulting in improved the artherogenic index (AI). Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) activities were brought to normal by H. indicum. It significantly elevated superoxide dismutase (SOD) and catalase (CAT) activities as well as increased reduced glutathione (GSH) concentration in liver. The intense liver fat deposition was seen in HCHF fed rats which were relatively low in H. indicum fed rats. Therefore, H. indicum has the ability to prevent obesity and associated metabolic disorders. PRACTICAL APPLICATIONS: Obesity and associated metabolic disorders are the most common threats to public health. Modern lifestyle and food habits are the main causes behind this malice, and the introduction of functional foods in daily diet is proved to be highly beneficial. Results of this study demonstrated that H. indicum can effectively attenuate obesity and its associated metabolic complications. Therefore, the current study has the merits to promote scientific knowledge of the dietary application of H. indicum as a functional food among the community.

Dietary total antioxidant capacity (TAC), general and central obesity indices and serum lipids among adults: An updated systematic review and meta-analysis

Background: In the present meta-analysis, we aimed to summarize the relationship between dietary total antioxidant capacity (TAC), general and central obesity indices and lipid profile in adult population. Methods: The electronic databases of Web of Sciences, PubMed, Scopus and Cochrane library were searched for relevant studies from inception to October 2019. The effect size was indicated as weighted mean difference (WMD) and 95% confidence intervals (CI) by using random effects model. The I² index and Cochran's Q-test were used for evaluating heterogeneity. Results: From 2,469 studies identified, thirty-four studies (nineteen cross-sectional studies, thirteen cohort studies, two case-control studies) were included in the meta-analysis. According to our results, higher categories of TAC were associated with significantly lower serum triglyceride concentartions (TG; WMD: -7.58; CI: -11.42, -3.75; P < 0.001) and waist circumference (WC; WMD: -1.17; 95% CI: -1.47, -0.87; P < 0.001); while no significant change in body mass index (BMI; WMD: -0.17; 95% CI: -0.35, 0.01; P = 0.12), high density lipoprotein cholesterol (HDL-C; WMD: 0.61; 95% CI: -0.16, 1.40; P = 0.12), low density lipoprotein cholesterol (LDL-C; WMD: 1.34; 95% CI: -0.61, 3.30; P = 0.17) and total cholesterol (TC; WMD: 1.19; 95% CI: -1.46, 3.855; P = 0.37) was reported. Conclusion: Higher dietary TAC was related to reduced prevalence of central obesity, reduced WC and TG concentrations in the current meta-analysis. Moreover, subgroup analysis showed that TAC measurement index, geographical area, dietary assessment tool, health status and gender were potential sources of heterogeneity.

Vitamin A Supplementation during Suckling and Postweaning Periods Attenuates the Adverse Metabolic Effects of Maternal High-Fat Diet Consumption in Sprague-Dawley Rats

BACKGROUND

Vitamin A (VA) has been demonstrated to be a regulator of adipose tissue (AT) development in adult obese models. However, little is known about the effect of VA on obesity-associated developmental and metabolic conditions in early life.

OBJECTIVES

We aimed to assess the effects of dietary VA supplementation during suckling and postweaning periods on the adiposity and metabolic health of neonatal and weanling rats from mothers consuming a high-fat diet (HFD).

METHODS

Pregnant Sprague-Dawley rats were fed a normal-fat diet (NFD; 25% fat; n = 2) or an HFD (50% fat; n = 2), both with 2.6 mg VA/kg. Upon delivery, half of the rat mothers were switched to diets with supplemented VA at 129 mg/kg, whereas the other half remained at 2.6 mg VA/kg. Four groups of rat pups were designated as NFD, NFD + VA, HFD, and HFD + VA, respectively. At postnatal day (P)14, P25, and P35, pups (n = 4 or 3/group) were killed. Body weight (BW), visceral white AT (WAT) mass, brown AT (BAT) mass, uncoupling protein 1 mRNA expression in BAT, serum glucose, lipids, adipokines, and inflammatory biomarkers, as well as serum and AT redox status were assessed.

RESULTS

Rat pups in the HFD group exhibited significantly higher BW, WAT mass, and serum glucose and leptin but reduced BAT mass compared with the NFD group. Without affecting the dietary intake, supplementing the HFD with VA significantly reduced the BW and WAT mass of pups but increased the BAT mass, significantly lowered the systemic and WAT oxidative stress, and modulated serum adipokines and lipids to some extent.

CONCLUSIONS

VA supplementation during suckling and postweaning periods attenuated metabolic perturbations caused by excessive fat intake. Supplementing maternal or infant obesogenic diets with VA or establishing a higher RDA of VA for specific populations should be studied further for managing overweight/obesity in early life.