The effects of antioxidants on exercise-induced lipid peroxidation in patients with COPD

Dietary patterns and micronutrients in respiratory infections including COVID-19: a narrative review

BACKGROUND

COVID-19 is a pandemic caused by nCoV-2019, a new beta-coronavirus from Wuhan, China, that mainly affects the respiratory system and can be modulated by nutrition.

METHODS

This review aims to summarize the current literature on the association between dietary intake and serum levels of micronutrients, malnutrition, and dietary patterns and respiratory infections, including flu, pneumonia, and acute respiratory syndrome, with a focus on COVID-19. We searched for relevant articles in various databases and selected those that met our inclusion criteria.

RESULTS

Some studies suggest that dietary patterns, malnutrition, and certain nutrients such as vitamins D, E, A, iron, zinc, selenium, magnesium, omega-3 fatty acids, and fiber may have a significant role in preventing respiratory diseases, alleviating symptoms, and lowering mortality rates. However, the evidence is not consistent and conclusive, and more research is needed to clarify the mechanisms and the optimal doses of these dietary components. The impact of omega-3 and fiber on respiratory diseases has been mainly studied in children and adults, respectively, and few studies have examined the effect of dietary components on COVID-19 prevention, with a greater focus on vitamin D.

CONCLUSION

This review highlights the potential of nutrition as a modifiable factor in the prevention and management of respiratory infections and suggests some directions for future research. However, it also acknowledges the limitations of the existing literature, such as the heterogeneity of the study designs, populations, interventions, and outcomes, and the difficulty of isolating the effects of single nutrients from the complex interactions of the whole diet.

Sweet-type star fruit supplementation controls oxidative stress status and enhances the community walking capacity among elderly Thai

BACKGROUND

Sweet-type Star fruit (SF) (Averrhoa carambola L.) is seasonal and more available for purchase in many markets in Thailand, when compared to the sour-type. But, its antioxidant activity results and potentially more modified supplement for elderly health during regular exercise in the community are unclear.

OBJECTIVE

This study aimed to evaluate the antioxidant activity and physical capacity from supplementation of sweet-type SF among elderly people performing home walking exercise.

METHODS

Mixing SF juice with honey industrially prepared the SF product. Its effects on oxidative stress status and physical capacity were studied in four groups; a supplement with walking exercise (n = 11, 67.00 ± 4.17 years), control (n = 12, aged 67.50 ± 5.58 years), supplementation (n = 11, aged 69.63 ± 7.14 years), and walking exercise (n = 12, aged 67.91 ± 4.33 years). Twenty grams or two teaspoons of supplement in warm water (150 mL) was the guideline for consumption twice daily for 4 weeks. In contrast, the walking exercise was prescribed with moderate intensity for 30 min, 3 days per week. Before and after the 4-week period, the oxidative stress status; glutathione (GSH), ascorbic acid (Vit C), total antioxidant capacity (TAC), and malondialdehyde (MDA), and 6-minute walking distance (6MWD) were evaluated.

RESULTS

Results after the 4-week period, showed that Vit C and TAC increased and the MDA decreased significantly in the supplementation group, except the GSH and 6MWD results. The GSH and Vit C slightly decreased in the walking exercise group, whereas, its TAC, MDA and 6MWD increased significantly. Finally, The GSH and Vit C did not decrease and MDA slightly decreased in the combined group, but, their TAC and 6MWD increased significantly.

CONCLUSION

Supplementation of the SF product during walking exercise possibly controls oxidative stress status and may enhance walking capacity.

Role of thioredoxin in chronic obstructive pulmonary disease (COPD): a promising future target

INTRODUCTION

Thioredoxin (Trx) is a secretory protein that acts as an antioxidant, redox regulator, anti-allergic, and anti-inflammatory molecule. It has been used to treat dermatitis and inflammation of the digestive tract. In the lungs, Trx has a significant anti-inflammatory impact. On the other hand, Chronic Obstructive Pulmonary Disease (COPD) is one of the significant causes of death in the developed world, with a tremendous individual and socioeconomic impact. Despite new initiatives and endless treatment trials, COPD incidence and death will likely escalate in the coming decades.

AREAS COVERED

COPD is a chronic inflammatory disease impacting the airways, lung parenchyma, and pulmonary vasculature. Oxidative stress and protease-antiprotease imbalances are thought to be involved in the process. The most popular respiratory inflammatory and allergic disorders therapies are corticosteroids and β-receptor agonists. These medications are helpful but have some drawbacks, such as infection and immunosuppression; thus, addressing Trx signalling treatments may be a viable COPD treatment approach. This review shall cover the pathophysiology of COPD, the pharmacognosy of anti-COPD drugs, including the assets and liabilities of each, and the role and mechanism of Trx in COPD treatment.

EXPERT OPINION

Limited research has targeted the thioredoxin system as an anti-COPD drug. Spectating the increase in the mortality rates of COPD, this review article would be an interesting one to research.

Systematic Review and Meta-Analysis of the Blood Glutathione Redox State in Chronic Obstructive Pulmonary Disease

The aim of this systematic review and meta-analysis was to assess the blood concentrations of the total and reduced forms of the low-molecular-weight antioxidant thiol glutathione (GSH) in chronic obstructive pulmonary disease (COPD) patients in comparison to healthy individuals. A literature search was conducted in the PubMed and Web of Science databases from inception until June 2020. In the 18 studies identified (involving a total of 974 COPD patients and 631 healthy controls), the pooled reduced GSH concentrations were significantly lower in patients with COPD than controls (SMD  =  -3.04, 95% CI = -4.42 to -1.67; p  <  0.001). By contrast, the pooled total GSH concentrations were significantly higher in patients with COPD than controls (SMD = 0.42, 95% CI = 0.11 to 0.73; p = 0.009). Our meta-analysis showed that the blood concentrations of reduced GSH, even in the presence of higher total GSH concentrations, were significantly lower in patients with COPD when compared to healthy controls. This suggests that an impaired antioxidant defense system plays an important role in the pathogenesis of COPD.

Effect of long-term vitamin E and selenium supplementation on urine F2-isoprostanes, a biomarker of oxidative stress

BACKGROUND

Cigarette smoking generates reactive oxidant species and contributes to systemic oxidative stress, which plays a role in the pathophysiology of chronic diseases. Nutrients with antioxidant properties, including vitamin E and selenium, are proposed to reduce systemic oxidative burden and thus to mitigate the negative health effects of reactive oxidant species.

OBJECTIVE

Our objective was to determine whether long-term supplementation with vitamin E and/or selenium reduces oxidative stress in smokers, as measured by urine 8-iso-prostaglandin F2-alpha (8-iso-PGF2α).

DESIGN

We measured urine 8-iso-PGF2α with competitive enzyme linked immunoassay (ELISA) in 312 male current smokers after 36 months of intervention in a randomized placebo-controlled trial of vitamin E (400IU/d all rac-α-tocopheryl acetate) and/or selenium (200µg/d L-selenomethionine). We used linear regression to estimate the effect of intervention on urine 8-iso-PGF2α, with adjustments for age and race.

RESULTS

Compared to placebo, vitamin E alone lowered urine 8-iso-PGF2α by 21% (p=0.02); there was no effect of combined vitamin E and selenium (intervention arm lower by 9%; p=0.37) or selenium alone (intervention arm higher by 8%; p=0.52).

CONCLUSIONS

Long-term vitamin E supplementation decreases urine 8-iso-PGF2α among male cigarette smokers, but we observed little to no evidence for an effect of selenium supplementation, alone or combined with vitamin E.

Urinary 8-hydroxydeoxyguanosine is a potential indicator for estimating pulmonary rehabilitation-induced oxidative stress in COPD patients

Chronic obstructive pulmonary disease (COPD) is the most common chronic lung disease and is an important cause of morbidity worldwide. The aim of this study was to evaluate whether pulmonary rehabilitation (PR) improves the oxidant/antioxidant imbalance, exercise capacity and health-related quality of life (HRQL) in patients with different stages of COPD. Eighteen stable COPD patients participated in 8-week PR; the exercise intensity was set at 70% of the VO2 peak. Subjects were divided into 2 groups: moderate to severe (stages II/III: n = 12) and very severe COPD with FEV1 < 30% predicted (stage IV: n = 6). In patients at stages II/III, PR improved exercise capacity (6-minute walking test: 431.2 ± 26.6 vs. 489.1 ± 26.5 m, P < 0.01 and shuttle walking test: 329.2 ± 41.4 vs. 378.2 ± 41.5 m, P < 0.01) and HRQL, whereas no significant change was observed in erythrocyte lipid peroxidation and urinary 8-hydroxydeoxyguanosine, a marker for DNA damage. In contrast, PR for stage IV patients did not improve exercise capacity and HRQL, but significantly increased urinary 8-hydroxydeoxyguanosine (14.5 ± 1.7 vs. 24.3 ± 2.6 ng/mg Cr, P < 0.05). In both groups, erythrocyte antioxidants (superoxide dismutase, glutathione peroxidase, and catalase) did not change significantly after PR. Thus, urinary 8-hydroxydeoxyguanosine is a useful indicator for the PR-induced oxidative stress in COPD patients. In conclusion, appropriate exercise program in COPD patients can improve exercise capacity and HRQL without further increase of oxidative stress. However, PR for very severe COPD patients enhanced exercise-induced oxidative stress.

Diet and vitamin D as risk factors for lung impairment and COPD

Epidemiologic and observational studies have shown an association between increased intakes of certain micronutrients and higher levels of lung function and health. The National Health and Nutrition Examination Surveys of the U.S. population have demonstrated repeatedly that increased intakes or serum levels of some micronutrients, including the vitamins E, D, C, and A, and carotenes are associated positively with forced expiratory volume in 1 second (FEV1). These findings are complemented by other observational studies, including the MORGEN study as well as the Seven Countries Study, both of which found micronutrient status had positive correlations with pulmonary function. In addition, epidemiologic studies have demonstrated that dietary intake patterns with increased intakes of fruit, vegetables, fish, vitamin E, and whole grains have been associated with a decreased development of chronic obstructive pulmonary disease (COPD) in smokers and nonsmokers, higher levels of FEV1, and decreased long-term COPD mortality. Diets high in refined food have been associated with accelerated longitudinal decline in FEV1 over 5 years. Taken together, these results suggest that micronutrient status may impact lung function, and that nutrition interventions could be a useful tool in a public health campaign aimed at the prevention of lung disease. Future research should focus on the effect of nutrition interventions on the natural history of lung disease.

Evaluation of the oxidant and antioxidant balance in the pathogenesis of chronic obstructive pulmonary disease

Chronic Obstructive Pulmonary Disease (COPD) is one of the most common chronic diseases and a major cause of morbility and mortality. An imbalance between oxidants and antioxidants (oxidative stress) has been proposed as a critical event in the pathogenesis of COPD. The increased oxidative stress in patients with COPD is the result of exogenous oxidants namely pollutants and cigarette smoke as well as endogenous oxidant production during inflammation. The aim of the present study was to clarify the hypothesis about the presence of an imbalance between oxidants and the antioxidant defences associated to COPD. In this study, we evaluated a biomarker of oxidative stress (malondialdehyde, a lipid peroxidation derived product) and non-enzymatic antioxidants (vitamin C and the sulphydryl groups) in COPD patients and healthy controls. The marker of oxidative stress was found to be significantly (p<0,001) higher in COPD patients when compared with the control group. No age dependent changes in the plasma levels of lipid peroxidation products were found. COPD patients had a significant (p<0,001) decrease in antioxidant status compared with control group. Our results show that oxidative stress is an important pathophysiologic change in COPD.

Oxidative stress and antioxidant defense mechanisms linked to exercise during cardiopulmonary and metabolic disorders

Oxidative stress has been implicated in the pathophysiology of multiple human diseases, in addition to the aging process. Although various stimuli exist, acute exercise is known to induce a transient increase in reactive oxygen and nitrogen species (RONS), evident by several reports of increased oxidative damage following acute bouts of aerobic and anaerobic exercise. Although the results are somewhat mixed and appear disease dependent, individuals with chronic disease experience an exacerbation in oxidative stress following acute exercise when compared to healthy individuals. However, this increased oxidant stress may serve as a necessary “signal” for the upregulation in antioxidant defenses, thereby providing protection against subsequent exposure to prooxidant environments within susceptible individuals. Here we present studies related to both acute exercise-induced oxidative stress in those with disease, in addition to studies focused on adaptations resulting from increased RONS exposure associated with chronic exercise training in persons with disease.

A systematic review of the role of vitamin insufficiencies and supplementation in COPD

BACKGROUND

Pulmonary inflammation, oxidants-antioxidants imbalance, as well as innate and adaptive immunity have been proposed as playing a key role in the development of COPD. The role of vitamins, as assessed either by food frequency questionnaires or measured in serum levels, have been reported to improve pulmonary function, reduce exacerbations and improve symptoms. Vitamin supplements have therefore been proposed to be a potentially useful additive to COPD therapy.

METHODS

A systematic literature review was performed on the association of vitamins and COPD. The role of vitamin supplements in COPD was then evaluated.

CONCLUSIONS

The results of this review showed that various vitamins (vitamin C, D, E, A, beta and alpha carotene) are associated with improvement in features of COPD such as symptoms, exacerbations and pulmonary function. High vitamin intake would probably reduce the annual decline of FEV1. There were no studies that showed benefit from vitamin supplementation in improved symptoms, decreased hospitalization or pulmonary function.

Malondialdehyde and superoxide dismutase correlate with FEV(1) in patients with COPD associated with wood smoke exposure and tobacco smoking

Tobacco smoking is the primary risk factor for chronic obstructive pulmonary disease (COPD). However, recent epidemiological studies have established domestic exposure to wood smoke and other biomass fuels as additional important risk factors, characteristic in developing countries. Oxidative stress is one of the mechanisms concerned with pathogenesis of COPD. However, the molecular mechanisms involved in the onset and progress of COPD associated with biomass and specifically that derived from wood smoke exposure remain unknown. We analyzed the relationship between forced expiratory volume in first second (FEV(1)) with plasma malondialdehyde (MDA) concentration and activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione-S-transferase (GST) in COPD patients associated with wood smoke (WSG; n = 30), tobacco smoking (TSG; n = 30), and healthy control subjects (HCG; n = 30). Differences between FEV(1) from WSG and TSG (58 +/- 22% and 51 +/- 24%, respectively) with HCG (100 +/- 6%) were observed (P < 0.01). Plasma MDA concentration was higher in both WSG and TSG (1.87 +/- 0.81 and 1.68 +/- 0.82 nmol/mL, respectively) compared with HCG (0.42 +/- 0.17 nmol/mL; P < 0.01). SOD activity showed a significant increase in both WSG and TSG (0.36 +/- 0.12 and 0.37 +/- 0.13 U/mL) compared with HCG (0.19 +/- 0.04 U/mL; P < 0.01). No differences were shown regarding GPx, GR, and GST activities between COPD and control groups. Inverse correlations were founded between MDA and SOD with FEV(1) in both COPD patients and control subjects (P < 0.001). These results indicate a role for oxidative stress in COPD associated with wood smoke similar to that observed with tobacco smoking in subjects who ceased at least 10 years previous to this study.

Oxidative stress in chronic obstructive pulmonary disease patients submitted to a rehabilitation program

Pulmonary rehabilitation (PR) improves physical capacity and health quality in patients with chronic obstructive pulmonary disease (COPD). However, the effect of exercise on oxidative stress markers in COPD patients is only partially known. This study was designed to evaluate the oxidative stress response to long-term exercise in patients with COPD enrolled in a PR program. Fifteen COPD patients (FEV1 < 60%), age between 50 and 60 years, ex-smokers, were separated in two groups: exercise-trained (n=8) and sedentary group (n=7). Exercise consisted of an 8-week conditioning program using a cycle ergometer (three times a week, 1h session). An endurance test (60% of maximal load in an incremental cycle test) was performed before and after PR. Blood samples were obtained at baseline and immediately after each endurance test. We measured the index of lipid peroxidation, thiobarbituric acid reactive species (TBARS), total radical-trapping antioxidant parameter (TRAP) and xanthine oxidase (XO) activity. TRAP was significantly different between the exercise-trained group and sedentary group of COPD patients. Baseline TBARS values were increased after the exercise training program but decreased after the endurance test. XO decrease after effort in the trained and untrained groups. The results suggest that patients with COPD are characterized by increased systemic and pulmonary oxidative stress markers both at rest as well as induced by cardiopulmonary exercise test and that PR program was associated with decreased systemic exercise-induced oxidative damage.

Effects of oral alpha-tocopherol on lung response in rat model of allergic asthma

OBJECTIVE AND BACKGROUND

Asthma is a chronic inflammatory disease in which an oxidant/antioxidant imbalance plays an important role. d-alpha-tocopherol (biologically the most active form of vitamin E) has redox properties and by scavenging the free radicals can act as an antioxidant. The aim of this study was to examine the effects of orally administered alpha-tocopherol in a rat model of allergic asthma.

METHODOLOGY

Actively sensitized rats (OA) were treated with alpha-tocopherol (400 mg/kg/day for 10 days) or vehicle; 1 h after the last dose, they were challenged with antigen aerosol. The antigen-induced airway hyperresponsiveness to direct bronchoconstrictor (serotonin), the inflammatory cell infiltrate and histological changes were determined 1 or 24 h after the antigen challenge.

RESULTS

Alpha-tocopherol pretreatment was not significantly effective at reducing the studied parameters when compared with controls, even though there was a tendency to a reduction in bronchial responsiveness and in eosinophil and neutrophil infiltration.

CONCLUSION

Alpha-tocopherol when administered in the chosen study design in an animal model of asthma had no major effect on airway inflammation. The effect of antioxidants deserves further evaluation.

α-Tocopherol and ascorbic acid supplementation reduced acute lung inflammatory response by cigarette smoke in mouse

OBJECTIVE

Short-term cigarette smoke (CS) exposure leads to acute lung inflammation through its influence over oxidants/antioxidants imbalance. Antioxidant vitamins such as ascorbic acid and alpha-tocopherol interact with oxidizing radicals. It is not clear if antioxidant supplementation can reduce inflammatory lung responses. Thus our aim was to analyze the effects of vitamin supplementation on the lungs of mice exposed to six cigarettes per day with histologic, cytological, and biochemical methods.

METHODS

C57BL/6 mice were exposed to ambient air (control) or CS from 3, 6, 9, 12, or 15 cigarettes daily for up to 5 d. Mice alveolar macrophages and polymorphonuclear cells were counted in the bronchoalveolar lavage. Groups of CS animals received 50 mg/kg of ascorbic acid daily and/or 50 mg/kg of alpha-tocopherol daily as an oral supplementation (CS+C, CS+E, CS+C+E, respectively) 12 h before CS exposure. Thiobarbituric acid-reactive substances were detected and western blot to nuclear factor-kappaB were performed in lung extracts; metalloprotease-12 and tumor necrosis factor-alpha positive alveolar macrophages were quantified in the lungs processed for immunohistochemistry of the animals exposed to the smoke from six cigarettes daily for 5 d.

RESULTS

The number of alveolar macrophages and polymorphonuclear cells in bronchoalveolar lavage (cells x 10(3)/mL) in mice exposed to CS were increased and CS with vitamin supplementation groups presented bronchoalveolar lavage cells similar to those of control. Thiobarbituric acid-reactive substances values were reduced in vitamin supplementation groups when compared with CS and the lower value was found in the CS+C+E group. Metalloprotease-12 and tumor necrosis factor-alpha were more evident in CS as much as nuclear factor-kappaB activation when compared with control and vitamin supplementation groups.

CONCLUSION

Our results showed that CS induced acute lung inflammation. The inflammatory process after cigarette exposures was reduced by ascorbic acid, alpha-tocopherol, or more efficiently by both vitamin supplementations.

Increased oxidative stress in patients with chronic obstructive pulmonary disease (COPD) as measured by redox status of plasma coenzyme Q10

STUDY OBJECTIVES

The percentage of oxidized coenzyme Q10 in total coenzyme Q10 (%CoQ-10) has been shown to indicate the degree of systemic oxidative stress. Chronic obstructive pulmonary disease (COPD) is regarded as a systemic disease that is linked to oxidative stress in its pathogenesis. In this study, the plasma %CoQ-10 levels in COPD patients were determined and assessed. In addition, the effect of oxygen supplementation on plasma %CoQ-10 was also evaluated.

MATERIAL AND METHODS

Thirteen COPD patients who had not received oxygen supplementation (COPD-Pt), five COPD patients who had received oxygen supplementation (COPD + O2) and 20 age-matched control subjects (CONTROL) were enrolled. We have also enrolled 83 young healthy non/slight smokers (smoking index <20 pack-year) and 24 young healthy smokers (smoking index > or = 20 pack-year) in order to assess the effect of smoking history on %CoQ-10 level. Their plasma was collected and plasma %CoQ-10 levels were determined and compared.

RESULTS AND CONCLUSION

The plasma %CoQ-10 of COPD-Pt was 6.3 +/- 2.3, significantly higher than that of CONTROL, 4.7 +/- 1.6 (p < 0.05), indicating an increased oxidative stress in the patients. In contrast, no significant difference in %CoQ-10 was observed between young healthy non/slight smokers (%CoQ-10 = 3.2 +/- 0.9) and young healthy smokers (%CoQ-10 = 3.7 +/- 1.3). Our observation of five COPD patients who received an oxygen supplementation revealed that their %CoQ-10 values (4.0 +/- 1.5) were significantly lower than those in COPD-Pt subjects (p < 0.05), suggesting that oxygen supplementation ameliorates the oxidative stress. In contrast, our study showed that no significant difference was observed among the three groups in plasma levels of Vitamin C or E. In conclusion, plasma %CoQ-10 levels are increased in COPD patients and oxygen supplementation attenuates this increasing effect by COPD. This implies that %CoQ-10 might be used practically to assess the COPD patients systemically.

Rehabilitation decreases exercise-induced oxidative stress in chronic obstructive pulmonary disease

The effect of exercise at different intensities as well as the effect of intensive supervised pulmonary rehabilitation on oxidative stress were studied for chronic obstructive pulmonary disease (COPD). Eleven patients with COPD and 11 healthy age-matched control subjects performed a maximal and submaximal exercise cycle ergometry test at 60% of peak workload. Patients with COPD performed these tests before and after 8 wk of pulmonary rehabilitation. Measurements were done before, immediately after, and 4 h after both exercise tests. At rest, increased oxidative stress was observed in patients compared with control subjects, as measured by urinary malondialdehyde (MDA; p < 0.05) and hydrogen peroxide (H2O2) in breath condensate (p < 0.05). In healthy control subjects, a significant increase in urinary MDA was observed 4 h after both exercise tests (p = 0.05), whereas H2O2 significantly increased immediately after maximal exercise (p < 0.05). In patients with COPD, before rehabilitation, reactive oxygen species-induced DNA damage in peripheral blood mononuclear cells, urinary MDA, and plasma uric acid were significantly increased after both exercise tests (p < 0.05), whereas no significant increase was observed in plasma MDA. In contrast, exhaled H2O2 was only significantly increased after maximal exercise (p < 0.02). Although after rehabilitation peak workload was increased by 24%, a similar oxidative stress response was found. Remarkably, a decrease in reactive oxygen species-induced DNA damage was detected after exercise at submaximal intensity despite increased exercise duration of 73%. In summary, patients with COPD had increased pulmonary and systemic oxidative stress both at rest and induced by exercise. In addition, pulmonary rehabilitation increased exercise capacity and was associated with reduced exercise-induced oxidative stress.

Stress regulation of sulfotransferases in male rat liver

Sulfotransferase (SULT) catalyzed sulfation is responsible for hormone regulation and xenobiotic detoxification. Induction of SULTs by various hormones has been reported. Stress regulation of SULTs has not been reported, however. Here we report that rat liver SULTs can be regulated by physical stress (forced running, EX) and chemical stress (the organophosphorus pesticide parathion, PS). Both EX and PS increased rat liver phenol-sulfating SULT1A1 and hydroxysteroid-sulfating SULT2A1 activities. The increase in SULT1A1 activity did not correlate with protein (Western blot) or mRNA (RT-PCR) results but correlated well with increased non-protein soluble thiols. This suggests a possible Cys modification mechanism for stress regulation of SULT1A1. In vitro studies on GSH/GSSG effects on SULT1A1 activity support this conclusion. In contrast, SULT2A1 activity following physical or chemical stress treatments correlated well with protein and mRNA levels. This suggests a stress regulation mechanism of SULT2A1 at the gene transcription level, possibly occurring via hormones.