Oxidative Stress In Healthy Subjects Research Articles

Effects of physical exercise on biomarkers of oxidative stress in healthy subjects: A meta-analysis of randomized controlled trials.

This meta-analysis investigated the effect of physical exercise (PE) on the levels of oxidative biomarkers in randomized controlled trials (RCTs) involving healthy subjects. We searched five databases for articles until May 1, 2023. A random-effect meta-analysis, subgroup analysis, meta-regressions as well as trim and fill method were conducted using STATA 11.0, involving ten articles. According to the results of the meta-analysis, PE had no significant effect on superoxide dismutase (SOD), glutathione peroxidase, and catalase levels. PE induced significant increase in total antioxidant status (standardized mean difference [SMD] 1.53, 95% CI 0.73-2.32), and PE could significantly reduce the level of malondialdehyde (MDA) (SMD -1.11, 95% CI -2.15 to -0.06). Sensitivity analyses and subgroup analyses showed that male participants, body mass index (BMI) <25, exercise duration between 1 and 12 weeks, resistance exercise or multicomponent exercise, and exercise of low or moderate intensity were associated with a significant PE-induced decrease in MDA concentrations. Meta-regression analysis identified the age of the participants as a confounder of the effect of PE on SOD levels. The older age of the subjects was associated in a gradient fashion with incident SOD levels. Further RCTs are required to investigate the optimal PE protocol for people of different ages and BMI as well as the effect of PE on oxidative stress.

Promotion of the Glutathione Defense System From Aronia Berry Extract With Acute Aerobic Exercise: A Double-Blind Randomized Controlled Trial in Healthy Adults.

ObjectivesThis study aimed to examine the protective effects of Aronia melanocarna berry extract (ABE) supplementation against the acute aerobic exercise (AAE) – induced oxidative stress in healthy subjects.MethodsA 8-week, randomized, double-blind, parallel, placebo-controlled trial were conducted with 70 healthy middle-aged adults. We assessed a battery of AAE-induced oxidate stress biomarkers at pre-exercise, immediately post-exercise, and 30-min post-exercise. The AAE challenge model, as a treadmill exercise for 30 minutes at 60% VO2max, was applied to load oxidative stress at the end of the study. A linear mixed-effect model was used to test differences of safety and effectiveness between two groups and Pearson's correlation coefficients assessed the statistical association.ResultsThe AAE-induced time course-dependent oxidative stress was well-observed in the placebo group regarding the glutathione peroxidase activity and glutathione availability for antioxidant defense; and erythrocyte malondialdehyde, interleukin-6, and lactate levels for oxidative damage. Meanwhile, the ABE supplementation improved the glutathione defense system by increasing glutathione availability and glutathione peroxidase activity during exercise and post-exercise recovery periods. In addition, the scatter plot and linear regression analysis revealed strong negative correlations of GSH availability with oxidized LDL and erythrocyte malonaldehyde levels.ConclusionsThese finding suggest ABE supplementation might affect to improve antioxidant defense mechanism in healthy adults with low fruit and vegetable intake.Funding SourcesThis research was supported by the BK21 FOUR (Fostering Outstanding Universities for Research) funded by the Ministry of Education (MOE, Korea) and the National Research Foundation of Korea (NRF), and the Bio & Medical Technology Development Program of the National Research Foundation (NRF), funded by the Ministry of Science & ICT (2012M3A9C4048761).

Meta-Analysis of Randomized Clinical Trials Evaluating Effectiveness of a Multivitamin Supplementation against Oxidative Stress in Healthy Subjects.

A meta-analysis has been widely applied to draw general conclusions using a set of studies with similar purposes and designs. This study aimed to perform a meta-analysis of six randomized placebo-controlled trials, independently conducted for the relationship between a plant-based multivitamin/mineral supplementation (PMS) and oxidative stress for 6 to 8 weeks, to provide overall estimates of those effects. In detail, linear mixed model analysis was first conducted on each study to obtain individual estimates; then, two types of meta-analysis were applied to combine the individual estimates from all available studies (overall meta-analysis) and region-specific studies (subgroup meta-analysis). In the meta-analysis, we selected 19 biomarker variables that overlapped in at least two studies and found 6 variables significant in at least one meta-analysis. The overall estimates of beta coefficients were 0.17 for vitamin C, 0.80 for vitamin B6, 0.46 for vitamin B12, 0.81 for folate, 0.36 for β-carotene, and −0.17 for oxidized LDL (ox-LDL). Subsequent association analysis revealed significant negative correlations between plasma free radical scavenging nutrients and plasma ox-LDL levels, indicating a general benefit of PMS in alleviating oxidative stress by providing exogenous oxidant scavengers.

Transcutaneous Electrical Nerve Stimulation of PC5 and PC6 Acupoints Increases Sympathovagal Balance but Not Oxidative Stress in Healthy Subjects: A Randomized Clinical Trial.

Transcutaneous electrical acupoint stimulation (TEAS) improves autonomic balance and reduces oxidative stress in subjects with chronic diseases, that decreases the risk of low-grade chronic inflammatory diseases, including cardiovascular diseases. However, these beneficial effects have never been demonstrated in healthy subjects. Objectives: To evaluate the acute effects of TEAS on autonomic balance and oxidative stress of healthy subjects. A randomized clinical trial was conducted with male healthy subjects (18-30 years old), randomly allocated to control (no intervention; n = 14), placebo (placebo intervention; n = 14) and TEAS group (at PC5 and PC6 acupoints; n = 13). The protocol consisted of accommodation (20 min), intervention (40 min), and recovery (30 min) periods. The acute effects of TEAS on hemodynamics were studied through measurements of heart rate, blood pressure and double product; on the autonomic nervous system by assessing heart rate variability; and on oxidative stress by quantifying reactive oxygen species in saliva samples, collected at the end of each period. TEAS increased heart rate and double-product compared to control and placebo groups (p < 0.01). Moreover, TEAS increased sympathetic and reduced parasympathetic tonus, increasing the sympathovagal balance compared to the control and placebo groups. However, TEAS exerted no effect on oxidative stress in saliva samples. In healthy subjects, TEAS at PC5 and PC6 acupoints acutely improved autonomic balance, increasing sympathetic and reducing parasympathetic tonus, reflecting little improvement on hemodynamic responses. Whether it could be used as a cardioprotective strategy remains uncertain since it exerted no effect on oxidative stress.

SOD Derived from Bacillus amyloliquefaciens GF423 Has Protection Against Exercise-Induced Oxidative Stress in Healthy Subjects

Abstract Objectives Excessive reactive oxygen species (ROS) can cause cellular damage, causing a variety of degenerative diseases such as atherosclerosis, ischemic heart disease, and cancer. SOD is thought to play a central role in scavenging ROS generated in cells by enhancing the antioxidant defense system, including catalase and glutathione peroxidase. This study aims to test the hypothesis that exogenous SOD administration can help to protect against oxidative stress encountered at very early stages in the daily life of healthy subjects. Methods A total of 80 healthy adults were assigned to either an intervention group consuming B. amyloliquefaciens GF423 SOD (250 IU/capsule) daily for 8 weeks or a placebo in a randomized, double-blind and parallel design. Aerobic exercise by a treadmill for 30 minutes at an intensity of 60% of the maximal oxygen consumption (VO2max) of each subject was used to induce oxidative stress at the beginning and end of the experimental period. Blood and urine samples were collected immediately after and 30 min after the exercise challenge to measure biochemical markers related to oxidative stress and inflammation. Results A single administration of exogenous SOD induced a marked decrease in urinary lipid peroxides and plasma pro-inflammatory cytokines as compared to placebo administration. Furthermore, repeated administration of exogenous SOD for eight weeks resulted in a significant improvement of erythrocyte redox balance. Conclusions These findings suggest that the supply of exogenous SOD may be useful to enhance the antioxidant defense capacity and anti-inflammatory response in response to exercise-induced oxidative stress. Funding Sources This work was supported by the Bio-Synergy Research Project (NRF-2012M3A9C4048761) from the Ministry of Science, ICT, and Future Planning, and the BK21PLUS (Brain Korea 21 plus) program (22a20130012143) from the Ministry of Education and the GenoFocus Inc, Republic of Korea.

Decreased Lipid Profile and Oxidative Stress in Healthy Subjects Who Underwent Whole-Body Cryotherapy in Closed Cryochamber with Subsequent Kinesiotherapy.

Objective The aim of the study was to estimate the impact of whole-body cryotherapy (WBC) and subsequent kinesiotherapy on oxidative stress and lipid profile when performed in a closed cryochamber on healthy subjects. Material and Methods The effect of ten WBC procedures lasting 3 minutes a day followed by a 60-minute session kinesiotherapy on oxidative stress and lipid profile in healthy subjects (WBC group, n = 16) was investigated. The WBC group was compared to the kinesiotherapy only (KT; n = 16) group. The routine parameters of oxidative stress (antioxidant enzymatic and nonenzymatic antioxidant status, lipid peroxidation products, total oxidative status (TOS), and oxidative stress index (OSI)) and lipid profile were estimated one day before the beginning and one day after the completion of the research program. Results After treatment, in the WBC group, a significant decrease of oxidative stress markers (TOS and OSI) and a significant increase of total antioxidant capacity were observed. The activity of plasma SOD-Mn and erythrocyte total SOD increased significantly in the WBC group. In the KT group, the erythrocyte activity of total SOD, CAT, and GR decreased significantly after the treatment. The levels of T-Chol and LDL-Chol decreased significantly after treatment in both groups, but the observed decrease of these lipid parameters in the WBC group was higher in comparison to the KT group. The level of TG decreased significantly after treatment in the WBC group only. Conclusion WBC performed in a closed cryochamber followed by kinesiotherapy improves lipid profile and decreases oxidative stress in healthy subjects.

Effect of exercise on glucose variability in healthy subjects: randomized crossover trial.

The aim of this study was to evaluate the acute effect of aerobic (AER) and eccentric (ECC) exercise on glucose variability, correlating it with circulating markers of inflammation and oxidative stress in healthy subjects. Sixteen healthy subjects (32 ± 12 years old) wore a continuous glucose monitoring system for three days. Participants randomly performed single AER and ECC exercise sessions. Glucose variability was evaluated by glucose variance (VAR), glucose coefficient of variation (CV%) and glucose standard deviation (SD). Blood samples were collected to evaluate inflammatory and oxidative stress markers. When compared with the pre-exercise period of 0-6 h, all the indices of glucose variability presented comparable reductions 12-18 h after both exercises (∆AER: VAR= 151.5, ∆CV% = 0.55 and ∆SD = 3.1 and ECC: ∆VAR = 221.2 , ∆CV% = 3.7 and ∆SD = 6.5). Increased interleukin-6 (IL-6) levels after AER (68.5%) and ECC (30.8%) (P<0.001) were observed, with no differences between sessions (P = 0.459). Uric acid levels were increased after exercise sessions (3% in AER and 4% in ECC, P = 0.001). In conclusion, both AER and ECC exercise sessions reduced glucose variability in healthy individuals. Inflammatory cytokines, such as IL-6, and stress oxidative markers might play a role in underlying mechanisms modulating the glucose variability responses to exercise (clinicalTrials.gov NCT02262208).

Genotoxic impact of long-term cigarette and waterpipe smoking on DNA damage and oxidative stress in healthy subjects

Although a plethora of studies have examined tobacco smoke-cancer disease association, the involvement of cellular genetic toxicity remains unclear. Therefore, the present study provides molecular evidence for a pathway involved in the DNA damage induced by long-term cigarette and waterpipe smoke in human subjects. The study population consisted of 45 subjects who were divided into three groups; healthy nonsmokers group, cigarette smokers group, and waterpipe smokers group. A questionnaire and consent form was distributed and signed by all participants. Total RNA was extracted from the blood using PAXgene Blood RNA Kit and mRNA expression levels of target genes were quantified by RT-PCR. Our results showed that 80% of the participants smoke 20–39 cigarettes/day, whereas 12% smoke more than 40 cigarettes/day. With regard to waterpipe smoke, the majority (46%) smoke more than 5 times/week. Both cigarette and waterpipe smokers showed increased the plasma levels 8-hydroxy-2'-deoxyguanosine (8-OHdG), of DNA damage marker. In addition, the mRNA expression levels of DNA repair genes (OGG1 and XRCC1) were significantly inhibited in both cigarette and waterpipe smokers groups by 30% and 60%, respectively. This was associated with a marked decrease (50%) in the expression of detoxifying genes (NQO1 and GSTA1) with an increase in CYP1A1 mRNA expression, a cancer-activating gene. Both cigarette and waterpipe smokers increased in the plasma concentrations of several toxic heavy metals such as Cd (130%), Pb (47%), and Ni (30%). In conclusion: the present findings clearly explore the genotoxic effect of cigarette and waterpipe smoking on human DNA.

Oxidative Stress and Inflammation, Key Targets of Atherosclerotic Plaque Progression and Vulnerability: Potential Impact of Physical Activity

Atherosclerosis, a complex cardiovascular disease, is a leading cause of mortality and morbidity worldwide. Oxidative stress and inflammation are both involved in the development of atherosclerotic plaque as they increase the biological processes associated with this pathology, such as endothelial dysfunction and macrophage recruitment and adhesion. Atherosclerotic plaque rupture leading to major ischemic events is the result of vulnerable plaque progression, which is a result of the detrimental effect of oxidative stress and inflammation on risk factors for atherosclerotic plaque rupture, such as intraplaque hemorrhage, neovascularization, and fibrous cap thickness. Thus, both are key targets for primary and secondary interventions. It is well recognized that chronic physical activity attenuates oxidative stress in healthy subjects via the improvement of antioxidant enzyme capacities and inflammation via the enhancement of anti-inflammatory molecules. Moreover, it was recently shown that chronic physical activity could decrease oxidative stress and inflammation in atherosclerotic patients. The aim of this review is to summarize the role of oxidative stress and inflammation in atherosclerosis and the results of therapeutic interventions targeting them in both preclinical and clinical studies. The effects of chronic physical activity on these two key processes are then reviewed in vulnerable atherosclerotic plaques in both coronary and carotid arteries.

Effect of Bifidobacterium lactis HN019 on inflammatory markers and oxidative stress in subjects with and without the metabolic syndrome.

Beneficial effects of probiotics have been reported on body weight, lipid and carbohydrate metabolism, inflammatory state and oxidative stress in healthy subjects and in many metabolic and inflammatory diseases. The aim of this study was to evaluate the effects of Bifidobacterium lactis HN019 on inflammatory state and nitro-oxidative stress in patients with and without the metabolic syndrome (MetS). The usual diets of the thirty-three subjects were supplemented with probiotic milk for 90 d. Inflammatory markers and oxidative measurements were performed. In relation to the baseline values, subjects in both groups showed a decrease in homocysteine (P=0·02 and P=0·03, respectively), hydroperoxides (P=0·02 and P=0·01, respectively) and IL-6 levels (P=0·02). Increases in adiponectin (P=0·04) and nitric oxide metabolites (NOx, P=0·001) levels were only seen in the group with the MetS in relation to the baseline values, whereas only the individuals without the MetS had increases in total radical-trapping antioxidant parameter levels (P=0·002). In conclusion, B. lactis HN019 have several beneficial effects on inflammatory and oxidative biomarkers in healthy subjects and the MetS patients. Patients with the MetS showed a specific improvement in adiponectin and NOx levels, whereas a specific favourable effect was shown in the antioxidant defenses in healthy subjects. If the results obtained in the present study are confirmed, supplementation of fermented milk with probiotics in healthy subjects and patients with the MetS must be further discussed.

Does at-home bleaching induce systemic oxidative stress in healthy subjects?

At-home bleaching is a technique characterized by the use of carbamide peroxide or hydrogen peroxide as a tooth-whitening agent. However, no data exist regarding systemic safety of this technique. The aim of this study was to investigate the effect of at-home bleaching on serum redox homeostasis. Twenty-nine healthy volunteers who requested tooth-whitening participated in this study. Specified bleaching trays were fabricated for the maxilla and mandible arches. Each participant was given two syringes containing 9% hydrogen peroxide gel to use for 30min/night for 14nights consecutively. To evaluate the redox status, the serum concentrations of malondialdehyde (MDA), total antioxidant capacity (TAC) and pro-oxidant-antioxidant balance (PAB) were measured. Blood samples were obtained in the morning prior to initiation of study and the morning after expiration of the bleaching period. The collected data were analyzed using Student's t-test with 95% confidence interval. Twenty-three subjects completed the study. MDA, PAB and TAC were significantly increased after the bleaching period (P=0.001, 0.001 and 0.002, respectively). At-home bleaching revealed the potential to disturb oxidant-antioxidant balance and induce oxidative stress. Its clinical relevance is unfavourable and potential side-effects of at-home bleaching should be considered.

Effect of body composition, aerobic performance and physical activity on exercise-induced oxidative stress in healthy subjects.

Oxidative stress could be the result of an increase in ATP resynthesis during exercise. The aim of the study was to compare prooxidant-antioxidant balance (PAB) disturbances induced by exercise at maximal intensity in young men with differing body compositions. Thirty-nine subjects were selected from 1549 volunteers aged 18-30, based on lean body mass (LBM) and body fat percentage (%BF), and then assigned into one of the following groups: control group (CON), including subjects with average LBM (59.0-64.3 kg) and average %BF (14.0-18.5%); high body fat (HBF) group, including subjects with high %BF (>21.5%) and average LBM; and high lean body mass (HLBM) group, including subjects with high LBM (>66.3 kg) and average %BF. Participants' physical activity was determined. A running test with a gradually increased load was used. Before and 3 minutes after exercise, total oxidative status (TOS) and total antioxidant capacity (TAC) were determined in the plasma, and the Oxidative Stress Index (OSI = TOS/TAC) was calculated. Maximal oxygen uptake (VO2max) was comparable in the HBF and HLBM groups (53.12±1.51 mL/kg and 50.25±1.27 mL/kg, respectively) and significantly lower compared to the CON group (58.23±1.62 mL/kg). The CON, HBF and HLBM groups showed similar significant (P<0.05) increases in TOS levels (36%, 35% and 31%, respectively). Post-exercise TAC increased by 8% in the HBF and HLBM groups (P<0.05), compared to the 3% increase in the CON group (P>0.05). There was significant negative correlation between OSI, measured before and after exercise, and participants' physical activity. There was no correlation between OSI and VO2max, BM, LBM, %BF and BMI. Exercise at maximal intensity causes a similar increase in TOS and in TAC in subjects with increased %BF and elevated content of LBM and regardless of body composition, the ratios of TOS/TAC concentrations before and after maximal-intensity exercise, have lower values in people with higher physical activity levels and are not dependent on aerobic performance (VO2max).

Airways oxidative stress, lung function and cognitive impairment in aging

An altered balance of oxidants/antioxidants is one of the pathological mechanisms of many age-dependent disorders. We aimed to investigate the age-related airways oxidative stress, using non invasive, safe and repeatable techniques; to evaluate the correspondence between systemic and local oxidative stress in healthy subjects of different age ranges; to analyse the correlation between systemic and local oxidative stress with lung function and with cognitive impairment. Thirty consecutive healthy high school graduated subjects (8 M, 22 F), divided in three ranges of age (< 35; between 35 and 60; > 60 years) were enrolled. All subjects underwent oxygen free radicals and exhaled nitric oxide measurement (by the diacron reactive oxygen metabolites test and by a rapid-response chemiluminescence nitric oxide analyzer), lung function tests, and cognitive impairment scales (Mini Mental State Examination and Geriatric Depression Scale). A significant increase of oxygen free radicals, exhaled nitric oxide, and Geriatric Depression Scale score and a significant decrease of forced expiratory volume in 1 second and forced expiratory vital capacity from younger to older subjects were identified. Moreover, the significant positive correlation between oxygen free radicals and exhaled nitric oxide, and between oxygen free radicals and exhaled nitric oxide with Geriatric Depression Scale score were found. The significant negative correlation between forced expiratory volume in 1 second and oxygen free radicals or exhaled nitric oxide was also demonstrated. Our data supports the role of progressive local oxidative stress in damaging the lung function and in inducing depression symptoms.

The relationship between concentrations of magnesium and oxidized low-density lipoprotein and Beta2-microglobulin in the serum of patients on the end-stage of renal disease.

The end-stage of renal disease is associated with increased oxidative stress and oxidative modification of low-density lipoproteins (LDLs). Beta2 microglobulin (beta2M) is accumulated in the serum of dialysis patients. Magnesium (Mg) plays a protective role in the development of oxidative stress in healthy subjects. We studied the relationship between concentrations of magnesium and oxidized LDL (ox-LDL) and beta2M in the serum of patients on the end stage of renal disease. In 96 patients on on-line- predilution hemodiafiltration, beta2M and intact parathormone were measured by radioimmunoassays. High-sensitivity C-reactive protein (hsCRP) and ox-LDL were measured using ΕLISA. Serum bicarbonate levels were measured in the blood gas analyser gas machine. We performed logistic regression analysis models to investigate Mg as an important independent predictor of elevated ox-LDL and high beta2M serum concentrations, after adjustment to traditional and specific for dialysis patients' factors. We observed a positive correlation of Mg with ox-LDL (r = 0.383, P = 0.001), but the association of Mg with beta2M, hsCRP, and serum bicarbonate levels was significantly inverse (r = -0.252, P = 0.01, r = -0.292, P = 0.004, and r = -0.282, P = 0.04 respectively). The built logistic-regression analysis showed that Mg act as a significant independent factor for the elevated ox-LDL and beta2M serum concentrations adjusting to traditional and specific factors for these patients. We observed a positive relationship between magnesium and acidosis status- related ox-LDL concentrations, but the inverse association between magnesium and beta2M serum concentrations in hemodialysis patients.

Oxidative Stress in Healthy Subjects with Cardiometabolic Risk Factors

WHO estimates that cardiometabolic diseases cause about 30% of deaths worldwide, Mexico is the second country with overweight/obesity. The presence of oxidative stress in healthy patients with cardiometabolic risk factors is poorly understood; therefore, the aim of this work was to determine the presence of oxidative stress in healthy subjects with cardiometabolic risk factors. The study was observational, descriptive, prospective, cross‐sectional with a sample of 49 healthy adult patients selected by non‐probabilistic sampling, medical history was evaluated and venous blood was obtained for plasma determination of carbonylated proteins.85.6% were female; the mean age was 40±11.1 years for women and 43.1±7.2 years for men. Lack of exercise was found in 53.1%, 25% were smokers, 96% had no diagnosis of diabetes mellitus or hypertension; 73.4% had a diagnosis of overweight/obesity. Cardiometabolic risk is present due to high waist circumference in 79.6%, and waist/hip ratio in 63%. Mean systolic blood pressure (SBP) was 116.98±12.01 mmHg and diastolic (DBP) was 74.63±10.66 mmHg. Carbonylated protein concentration in plasma was 0.457±0.025 nmol/mg of proteins. We found positive Pearson Correlations between: a) SBP/DBP and BMI diagnosis (0.399, p&lt;0.017), age (0.035, p&lt;0.035) and sex (0.362, p&lt;0.010); and b) BMI with carbonylated proteins (0.376, p&lt;0.008). Healthy subjects have high cardiometabolic risk in the presence of carbonylated proteins, associated with BMI. It is therefore important to reduce these risk factors and thereby prevent comorbidities.

Antioxidant Status in Healthy Humans after Acute Consumption of Juçara Fruits (Euterpe edulis)

Source of support: Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES).This study aimed evaluating the effect of acute consumption of juçara juice (Euterpe edulis) rich in anthocyanin on biomarkers of oxidative stress in healthy subjects. This cross‐over clinical trial used water as control. Eleven volunteers were evaluated 4 times, before consumption and 1h, 2h and 4h after the intake of juice or water. The parameters evaluated were: ferric reducing antioxidant potential (FRAP), uric acid, glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT) and lipid hydroperoxides (LH). Analyses of variance for repeated measures revealed a significant effect of this treatment on FRAP and GPx. A moderate correlation was observed between FRAP and uric acid (r = 0.31). A significant interaction between type of treatment and time on lipid oxidation (HL) was also found. After ingestion of juice, relative average changes showed within the 2nd hour maximum elevation in the enzymatic activities of SOD (34.3%), CAT (18%) and GPx (8.5%), was reached. The juçara juice ingestion showed effect on the for the FRAP and enzymatic activity of GPx and interaction of lipid peroxidation that decreased over time. Further studies that investigate the antioxidant properties of the fruit juçara in the human are needed.

Acute effect of sorghum flour-containing pasta on plasma total polyphenols, antioxidant capacity and oxidative stress markers in healthy subjects: A randomised controlled trial

It has been previously reported that pasta containing wholegrain sorghum flour exhibits high content of polyphenols and antioxidant capacity and hence might enhance antioxidant status and reduce markers of oxidative stress in vivo; however no clinical studies have yet been reported. Therefore, the present study assessed the effect of pasta containing red or white wholegrain sorghum flour on plasma total polyphenols, antioxidant capacity and oxidative stress markers in humans. The study was registered with the Australian New Zealand Clinical Trials Registry (ACTRN: 12612000324819). In a randomised crossover design, healthy subjects (n = 20) consumed three test meals of control pasta (CP), 30% red sorghum pasta (RSP) or 30% white sorghum pasta (WSP), 1-2 wk apart. The test meals were consumed as breakfast after an overnight fast. Blood samples were obtained at fasting and 2 h after consumption and analysed for total polyphenols, antioxidant capacity, superoxide dismutase (SOD) activity, protein carbonyl and 8-isoprostanes. Compared to baseline, the 2 h post-prandial levels following the RSP meal of plasma polyphenols, antioxidant capacity and SOD activity were significantly (P < 0.001) higher while the protein carbonyl level was significantly lower (P = 0.035). Furthermore, net changes in polyphenols, antioxidant capacity and SOD activity were significantly (P < 0.001) higher while protein carbonyl were significantly (P = 0.035) lower following consumption of the RSP meal than the CP meal. The results demonstrated that pasta containing red wholegrain sorghum flour enhanced antioxidant status and improved markers of oxidative stress in healthy subjects.

Inspiratory Muscle Exercise Reduces Lipoperoxidation in Obese and Healthy Subjects: A Pilot Study

IntroductionHigh‐intensity inspiratory exercise seems to increase oxidative stress in healthy subjects. Although obesity is related to impaired inspiratory muscle function, the acute effects of the inspiratory exercise remain unclear in obese subjects.MethodsWe studied 10 obese (35 ± 3 kg/m2; 32 ± 6 years old) and 10 healthy subjects (23 ± 2 kg/m2; 24 ± 5 years old). Maximal inspiratory pressure (PImax) was assessed by a pressure transducer. Blood sample was collected to assess thiobarbituric acid reactive substances (T‐BARS) before and after the inspiratory exercise performed in different days to inspiratory exercise without load maintained for 30 min, inspiratory exercise at 30% PImax maintained for 30 min and inspiratory exercise at 60% PImax maintained until reach the fatigue.ResultsInspiratory muscle strength was similar in obese and healthy subjects. Inspiratory exercise performed at 60% PImax reduced T‐BARS in obese (from 6 ± 2 nmol MDA/mL to 4 ± 2 nmol MDA/mL) and in healthy subjects (from 7 ± 4 nmol MDA/mL to 5 ± 3 nmol MDA/mL, ANOVA: Time= 0,003; Group= 0,52; Interaction= 0,98). As expected, inspiratory exercise performed without load and at 30% PImax did not change T‐BARS in obese and healthy subjects.ConclusionThis study shows that acute inspiratory exercise may reduce lipoperoxidation in humans.

The effect of glucose ingestion on inflammation and oxidative stress in obese individuals

Ingestion of 75 g glucose during an oral glucose tolerance test (OGTT) increases systemic inflammation and oxidative stress in healthy subjects and patients with type 2 diabetes mellitus, but the effect in overweight/obese nondiabetic individuals is uncertain. The aim of the present study was to determine the effect of an OGTT on plasma concentrations of inflammatory cytokines and peroxides in 33 subjects with body mass index >27 kg/m 2. After an overnight fast, blood samples were taken from participants immediately before and at 30, 60, 90, and 120 minutes after ingestion of 75 g glucose. Plasma glucose, insulin, free fatty acid, interleukin (IL)-6, tumor necrosis factor α, and peroxides were measured during the tests. Plasma IL-6 concentrations decreased (13%) significantly ( P < .001) at 30 and 60 minutes, whereas plasma peroxide concentrations decreased slightly (3%, P = .003) at 30 minutes during the tests. The 30-minute decrease in plasma IL-6 was correlated significantly and inversely with the concomitant increase in plasma insulin ( r = −0.410, P = .02) and with the ratio of insulin to glucose at 30 minutes during the OGTT ( r = −0.366, P = .04). These data suggest that plasma concentrations of IL-6 are acutely decreased possibly because of the predominance of the anti-inflammatory effect of hyperinsulinemia over the proinflammatory effect of hyperglycemia after ingestion of a large quantity of glucose in obese individuals.

Effect of Short-Term Ketogenic Diet on Redox Status of Human Blood

The present study investigated the effect of a ketogenic diet on the blood redox status of healthy female subjects. Twenty healthy females with mean body mass index of 21.45 +/- 2.05 kg/m(2) were provided a low-carbohydrate (55 +/- 6 g; 13% total energy), high-fat (138 +/- 16 g; 74% total energy), calorie-restricted (-465 +/- 115 kcal/d) diet. The followings were tested prior to and after 14 days consumption of the diet: Whole body, body weight and total body fat; blood, complete blood count, red blood cells, white blood cells, hemoglobin, and hematocrit; plasma, 3-beta-hydroxybutyrate, total antioxidative status, and uric acid; red blood cells, total sulfhydryl content, malondialdehyde, superoxide dismutase activity, and catalase activity. After 14 days, weight loss was significant whereas no changes were detected in body fat. No alterations were observed in blood count or morphology. 3-beta-hydroxybutyrate, total antioxidative status, uric acid, and sulfhydryl content were significantly increased. There were no alterations in malondialdehyde, or superoxide dismutase or catalase activity. The present study demonstrates that 14 days of a ketogenic diet elevates blood antioxidative capacity and does not induce oxidative stress in healthy subjects.