The role of O3 exposure and physical activity status on redox state, inflammation, and pulmonary toxicity of young men: A cross-sectional study.

The exposure to traffic-related air pollutants, such as NO2 and O3, are associated with detrimental health effects, becoming one of the greatest public health issues worldwide. Exercising in polluted environments could result in harmful outcomes for health and may blunt the physiological adaptations of exercise training. This study aimed to investigate the influence of physical activity and O3 exposure on redox status, an inflammatory marker, response to stress, and pulmonary toxicity of healthy young individuals. We performed a cross-sectional study with 100 individuals that, based on their exposure to O3 and physical fitness (PF) level, were distributed in four groups: Low PF + Low O3; Low PF + High O3; High PF + Low O3; High PF + High O3. We evaluated personal exposure to NO2 and O3, physical activity level, variables of oxidative stress (SOD, ROS, CAT, GSH, TBARS), pulmonary toxicity (CC16), and inflammatory mediators (IL-1ß, IL-4, IL-6, IL-10, TNF-α, HSP70). Spearman correlation test to check the association among the variables was used and to compare groups we used one-way ANOVA followed by Bonferroni's post hoc and Kruskal Wallis test followed by Dunn's post hoc. O3 levels correlated with physical activity (r = 0.25; p = 0.01) but not with age or markers of body composition (p > 0.05). The individuals with high physical fitness that were less exposed to O3 presented higher CAT activity (p < 0.001), lower TBARS (p < 0.01) and IL-1ß concentrations (p < 0.01), higher IL-6 (p < 0.05) and IL-10 concentrations (p < 0.05), lower IL-6:1L-10 ratio (p < 0.05), lower CC16 levels (p < 0.05), and higher HSP70 concentration (p < 0.05). Physical activity could result in higher exposure to O3 that could partially blunt some exercise adaptations, while high physical fitness improved the antioxidant defense system, systemic inflammatory mediators, and pulmonary toxicity.

Exposure to fine particulate matter partially counteract adaptations on glucose metabolism, oxidative stress, and inflammation of endurance exercise in rats.

BACKGROUND: Long-term exposure to air pollution triggers metabolic alterations along with oxidative stress and inflammation, while exercise interventions are widely used to improve those parameters. OBJECTIVE: Our study aimed to determine the effects of subchronic exposure to particulate matter 2.5 (PM2.5) and endurance exercise training on glucose metabolism, oxidative stress, and inflammation of the heart and gastrocnemius muscle of rats. MATERIAL AND METHODS: Thirty-two male Wistar rats were assigned to 4 experimental groups: Untrained; Endurance training (ET); Untrained + PM2.5; Endurance training + PM2.5. Rats exposed to air pollution received 50 µg of PM2.5 via intranasal instillation daily for 12 weeks. Exercised groups underwent endurance training, consisting in running on an electronic treadmill (70% of maximal capacity, 5 days/week, 5 times/week) for 12 weeks. Glucose metabolism markers, redox state, and inflammatory variables were evaluated in the heart and gastrocnemius muscle. RESULTS: ET and ET + PM2.5 group had lower body mass gain and higher exercise capacity, and higher glycogen concentration in the heart and gastrocnemius muscle. In the heart, ET and ET + PM2.5 groups had higher levels of GSH, and lower TBARS and TNF-α concentrations. In the gastrocnemius muscle, the ET group showed higher leptin and lower TBARS and IL-1ß concentrations, ET and ET + PM2.5 showed higher superoxide dismutase activity and ROS content. CONCLUSION: PM2.5 exposure partially blunts metabolic and inflammatory adaptations in heart and gastrocnemius muscle tissues induced by exercise training.

Exposure to O3 and NO2 in physically active adults: an evaluation of physiological parameters and health risk assessment.

The gaseous air pollutants ozone (O3) and nitrogen dioxide (NO2) have a large public health relevance and trigger environmental health risk. On the other hand, despite the health benefits, exercise practices might increase the susceptibility to air pollutants exposure. However, there are innumerous lifestyle factors besides physical activity habits that must be considered in the daily air pollution exposure and are still not fully comprehended. This study aimed to evaluate the effects of O3 and NO2 exposure on cardiorespiratory fitness, lipid accumulation product (LAP), and environmental health risk during the entire daily routine of physically active adults that exercise in outdoor and indoor environments. One hundred and twenty healthy young men were assigned to untrained (n = 52), indoor exercise (n = 36), and outdoor exercise (n = 32) groups, following their lifestyle exercise habits, and O3 and NO2 were assessed by personal monitoring. Exercised groups demonstrated higher healthy eating index (HEI) (p < 0.001), physical activity (PA) (p < 0.001), metabolic equivalent of task (MET) (p < 0.001), and peak oxygen uptake VO2peak (p < 0.001), while outdoor group had lower LAP index (p < 0.001) and higher O3 concentration (p = 0.0442). Environmental health risk demonstrated no difference (p > 0.05). The higher O3 concentration was positively correlated with the risk quotient (p = 0.003) and MET (p = 0.020), and a negative correlation between LAP and VO2peak was observed (p < 0.001). In conclusion, physically active individuals might have a lower risk of developing cardiovascular and metabolic diseases despite the higher O3 concentration exposure, and the exposure during exercise did not represent an additional health risk.

Should I stay or should I go: Can air pollution reduce the health benefits of physical exercise?

The urbanization process resulted in incredible achievements for society, unfortunately together with economic, social, and technological development it deteriorates air quality and encourages sedentary behavior. Air pollution inhalation is responsible for a massive negative health effect. The practice of regular physical exercise is strongly encouraged to achieve a healthy lifestyle. However, particularly during a physical exercise session, the respiratory system undergoes some physiological adaptations that lead to an increase in the volume of inhaled air, so exercising in a polluted environment would consequently augment the number of pollutants inhaled. In this scenario, would it be safer to stay physically inactive? Or to choose an indoor facility to exercise? Or to keep performing outdoor activities once the benefits achieved with exercise will overcome the possible damage caused by additional exposure to air pollution? Currently, these questions still do not have a decisive answer, so we designed a hypothesis to be tested in which exercise would be beneficial regardless of the chosen place. Outdoor and indoor pollution are both equally harmful to health, however, we do not know if it would have a difference to exercise in one of them.

Quantification of DNA Damage in Different Tissues in Rats with Heart Failure.

BACKGROUND: Chronic heart failure (CHF) is a complex syndrome which comprises structural and functional alterations in the heart in maintaining the adequate blood demand to all tissues. Few investigations sought to evaluate oxidative DNA damage in CHF. OBJECTIVE: To quantify the DNA damage using the comet assay in left ventricle (LV), lungs, diaphragm, gastrocnemius and soleus in rats with CHF. METHODS: Twelve male Wistar rats (300 to 330 g) were selected for the study: Sham (n = 6) and CHF (n = 6). The animals underwent myocardial infarction by the ligation of the left coronary artery. After six weeks, the animals were euthanized. It was performed a cell suspension of the tissues. The comet assay was performed to evaluate single and double strand breaks in DNA. Significance level (p) considered < 0.05. RESULTS: The CHF group showed higher values of left ventricle end-diastolic pressure (LVEDP), pulmonary congestion, cardiac hypertrophy and lower values of maximal positive and negative derivatives of LV pressure, LV systolic pressure (p < 0.05). CHF group showed higher DNA damage (% tail DNA, tail moment and Olive tail moment) compared to Sham (p < 0.001). The tissue with the highest damage was the soleus, compared to LV and gastrocnemius in CHF group (p < 0.05). CONCLUSION: Our results indicates that the CHF affects all tissues, both centrally and peripherically, being more affected in skeletal muscle (soleus) and is positively correlated with LV dysfunction.

Air pollution inhalation during acute exercise is dependent of the body mass index and ventilation of young men.

Obesity and physical inactivity threaten human health, and both could be solved with exercise. However, a higher amount of pollutants is inhaled during exercise. Exposure to air pollution increases the incidence and progression of diseases. Therefore, the aim of the study was to investigate the rate of pollution inhalation of lean, overweight, and obese individuals in a low and high-intensity hypothetical exercise session. Healthy sedentary men (n = 135) classified as lean, overweight, or obese were enrolled in our study. All participants performed a cardiopulmonary exercise testing (CPX) to collect ventilation rate (VE) data, which was used to predict total ventilation and pollutant inhalation of a 5-km running session. Air pollutant concentration of São Paulo City, Brazil was evaluated and the toxicological risk was estimated based on the potential intake dose. The concentrations of PM2.5 were 29.57 µg/m3 and 51.71 µg/m3, PM10 were 45.85 µg/m3 and 74 µg/m3, NO2 were 63.71 µg/m3 and 66.65 µg/m3, and O3 were 69 µg/m3 and 37 µg/m3, respectively in the summer and winter. In the hypothetical exercise session, total VE and time in both the first and second threshold were increased in the obese group (p < 0.001) (p < 0.001). The inhalation of PM2.5, PM10, NO2, and O3, during the hypothetical session, was increased in obese individuals (p < 0.001). Obese individuals should be considered a susceptible population, once they are more exposed to air pollution during exercise.

Stem Cell Transplantation and Physical Exercise in Parkinson's Disease, a Literature Review of Human and Animal Studies.

The absence of effective and satisfactory treatments that contribute to repairing the dopaminergic damage caused by Parkinson's Disease (PD) and the limited recovery capacity of the nervous system are troubling issues and the focus of many research and clinical domains. Recent advances in the treatment of PD through stem cell (SC) therapy have recognized their promising restorative and neuroprotective effects that are implicated in the potentiation of endogenous mechanisms of repair and contribute to functional locomotor improvement. Physical exercise (PE) has been considered an adjuvant intervention that by itself induces beneficial effects in patients and animal models with Parkinsonism. In this sense, the combination of both therapies could provide synergic or superior effects for motor recovery, in contrast with their individual use. This review aims to provide an update on recent progress and the potential effectiveness of SC transplantation and PE for the treatment of locomotor deficits in PD. It has reviewed the neuropathological pathways involved in the classical motor symptoms of this condition and the mechanisms of action described in experimental studies that are associated with locomotor enhancement through exercise, cellular transplantation, and their union in some neurodegenerative conditions.

Aerobic training reduces oxidative stress in skeletal muscle of rats exposed to air pollution and supplemented with chromium picolinate.

OBJECTIVE: The purpose of this study was to investigate the effects of chromium picolinate (CrPic) supplementation associated with aerobic exercise using measures of oxidative stress in rats exposed to air pollution. METHODS: Sixty-one male Wistar rats were divided into eight groups: residual oil fly ash (ROFA) exposure and sedentary (ROFA-SED); ROFA exposure, sedentary and supplemented (ROFA-SED-CrPic); ROFA exposure and trained (ROFA-AT); ROFA exposure, supplemented and trained (ROFA-AT-CrPic); sedentary (Sal-SED); sedentary and supplemented (Sal-SED-CrPic); trained (Sal-AT); and supplemented and trained (Sal-AT-CrPic). Rats exposed to ROFA (air pollution) received 50 µg of ROFA daily via intranasal instillation. Supplemented rats received CrPic (1 mg/kg/day) daily by oral gavage. Exercise training was performed on a rat treadmill (5×/week). Oxidative parameters were evaluated at the end of protocols. RESULTS: Trained groups demonstrated lower gain of body mass (P < .001) and increased exercise tolerance (P < .0001). In the gastrocnemius, trained groups demonstrated increased SOD activity (P < .0001) and decrease levels of TBARS (P = .0014), although CAT activity did not differ among groups (P = .4487). CONCLUSION: Air pollution exposure did not lead to alterations in oxidative markers in lungs and heart, and exercise training was responsible for decreasing oxidative stress of the gastrocnemius.

Resistance training and L-arginine supplementation are determinant in genomic stability, cardiac contractility and muscle mass development in rats.

L-arginine supplementation has been related to increased maximum strength and improvement of hemodynamic parameters in several diseases. The aim of our study was to evaluate the effect of L-arginine supplementation and resistance training on muscle mass, hemodynamic function and DNA damage in healthy rats subjected to a low-arginine concentration diet. Twenty three Wistar rats (290-320g) were divided into 4 groups: Sedentary (SED-Arg, n = 6), Sedentary+Arg (SED+Arg, n = 6), Resistance Training (RT-Arg, n = 5), Resistance Training+Arg (RT+Arg, n = 6). Trained animals performed resistance training protocol in a squat apparatus adapted for rats (4 sets of 10-12 repetitions, 90s of interval, 4x/week, 65-75% of One Maximum Repetition, for 8 weeks). Comet assay was performed to measure DNA damage in leukocytes. The resistance training induced higher muscle mass in trained groups. The L-arginine supplementation increased both gastrocnemius and left ventricle to body mass ratio and increased left ventricle contractility without changing hemodynamic variables. The SED+Arg group showed higher concentration of extracellular heat shock protein 72 (eHSP72) and total testosterone, as well as lower uric acid concentration in blood versus SED-Arg group. The administration of isolated L-arginine supplementation and its association with resistance training promoted less damage in leukocytes DNA. In conclusion, the L-arginine supplementation showed synergistic effect with resistance training regarding leukocyte genomic stability in a low-L-arginine diet scenario.

Long-term intake of saccharin decreases post-absortive energy expenditure at rest and is associated to greater weight gain relative to sucrose in wistar rats.

BACKGROUND: Non-nutritive sweeteners (NNS) have been associated with increased prevalence of obesity. In previous studies, we demonstrated that saccharin could induce an increase in weight gain either when compared to sucrose or to a non-sweetened control at a similar total caloric intake. These data raised the hypothesis that reduced energy expenditure (EE) could be a potential mechanism explaining greater weight gain with saccharin use in rats. The aim of the present study was to compare long-term energy expenditure at rest between rats using saccharin or sucrose and correlate it with weight gain. . METHODS: In the present study, we examine the potential impact of saccharin compared to sucrose in the EE of Wistar rats. In a controlled experiment of 17 weeks, 24 Wistar rats were divided into 2 groups: saccharin-sweetened yogurt (SAC) or sucrose-sweetened yogurt (SUC), plus a free chow diet. Only rats that consumed at least 70% of the offered yogurt were included. EE (kcal/day) was determined at rest through open circuit indirect calorimetry system in the early post-absorptive period with determinations of both VO2 consumption and CO2 production. Measurements were evaluated at baseline, 5 and 12 weeks of dietary intervention. Weight gain, caloric intake (from yogurt, from chow and total) were determined weekly. RESULTS: Body weight and EE were similar between groups at baseline: (p = .35) and (p = .67) respectively. At the end of the study, SAC increased total weight gain significantly more in relation to SUC (p = .03). Cumulative total caloric intake (yogurt plus chow) was similar between groups during the whole period (p = .54). At 12 weeks, the EE was smaller in SAC compared to SUC (p = .009). Considering both groups, there was a strong negative correlation between total weight gain and change in EE observed [r(20) = -.61, p = .003]. However, when analyzing the groups separately we found that SUC maintained this inverse correlation [r(8) = -.68, p = .03], while SAC did not [r(10) = -.33, p = .29]. CONCLUSION: These data support the hypothesis that long-term use of saccharin may blunt post-absorptive EE at rest in Wistar rats, which is related to weight gain. On the other hand, long-term sucrose intake can increase energy expenditure in rats. This effect combined can explain, at least partially, the weight gain increases associated to saccharin in relation to sucrose in these animals.

Effects of l-arginine supplementation associated with continuous or interval aerobic training on chronic heart failure rats.

OBJECTIVE: Chronic heart failure (CHF) is related with exercise intolerance and impaired nitric oxide (NO) production, which can lead to several functional capacity alterations. Considering the possible superiority of aerobic interval training compared to continuous training and the capacity of l-arginine to restore the NO pathway, the aim of the present study was to investigate whether these treatments are beneficial to exercise capacity, muscle mass preservation and hemodynamic, inflammatory and oxidative stress parameters in CHF rats. METHODS: Thirty-eight male Wistar rats post 6weeks of myocardial infarction (MI) surgery were randomly assigned into 6 CHF groups: sedentary (SED, n=6); SED+Arg (n=7); ACT (n=8); ACT+Arg (n=5); AIT (n=7); AIT+Arg (n=5). Exercise test capacity (ETC) was performed pre and post 8weeks of intervention. Supplemented rats received Arg (1g/kg) by oral gavage (7×/week). Exercise training was performed on a rat treadmill (5×/week). Hemodynamic variables, tissue collection, congestion, inflammatory cytokines, and oxidative parameters were evaluated at the end of protocols. RESULTS: All trained groups showed a superior exercise capacity compared to SED groups on the post-intervention test (p<0.0001). Pulmonary congestion was attenuated in AIT and AIT+Arg compared with the SED group (p<0.05). Left ventricular end-diastolic pressure (LVEDP) was lower in ACT+Arg, AIT, and AIT+Arg groups than SED group (p<0.05). Association of AIT with Arg supplementation was able to improve hemodynamic responses (left ventricular systolic pressure (LVSP), systolic blood pressure (SBP), +dP/dtmax, and -dP/dtmax (p<0.05), likewise, decrease muscular and renal lipid peroxidation and tumor necrosis factor (TNF)-α, and increase interleukin (IL)-10/TNF-α plasmatic levels (p<0.01). Groups that associated aerobic exercise with Arg supplementation (ACT+Arg and AIT+Arg) revealed higher gastrocnemius mass compared to the SED group (p<0.01). CONCLUSIONS: Both aerobic training protocols were capable to improve aerobic capacity, and the association with Arg supplementation was important to attenuate muscle loss. Moreover, interval training associated with Arg supplementation elicits greater improvements in hemodynamic parameters, contributing to reduction in pulmonary congestion, and demonstrated particular responses in the inflammatory profile and in the antioxidant status.

High-intensity resistance training alone or combined with aerobic training improves strength, heart function and collagen in rats with heart failure.

BACKGROUND: Resistance training (RT) has been associated with positive responses in patients with cardiovascular disease, and when it is combined with continuous aerobic training (CAT), favorable adaptations appear to be even more pronounced. However, the effects of high-intensity RT alone or in combined with CAT in the case of heart failure (HF) is not completely elucidated. METHODS: 28 male Wistar rats with HF (90 days old) were allocated to 4 groups: high-intensity RT (RT, n=7), CAT (CAT, n=7), RT and CAT (RT+CAT, n=7) and sedentary (Sed, n=7). Trained animals were subjected to a RT protocol in an adapted squat apparatus for rats (4 bouts, 6-8 reps, 90 s interval, 3×/week, 75% to 85% of one maximum repetition (1RM) for 8 weeks). The animals subjected to CAT performed it 3×/week during 50 min/session at 16 m/min. The animals of the combined exercise regimen performed both the RT and CAT exercise protocols. RESULTS: The left ventricular end-diastolic pressure (LVEDP), collagen volume fraction and right ventricular hypertrophy were lower in RT, CAT and RT+CAT groups when compared to Sed group (P<0.05) for all outcomes. Regarding the inflammatory profile, only the CAT group showed greater IL-10 concentrations. CONCLUSION: We concluded that RT combined with CAT was able to improve the strength in animals with HF, which was associated to improvement in ventricular structure and function.

Quantification of DNA Damage in Different Tissues in Rats with Heart Failure / Quantificação de Dano em DNA em Diferentes Tecidos em Ratos com Insuficiência Cardíaca

Abstract Background: Chronic heart failure (CHF) is a complex syndrome which comprises structural and functional alterations in the heart in maintaining the adequate blood demand to all tissues. Few investigations sought to evaluate oxidative DNA damage in CHF. Objective: To quantify the DNA damage using the comet assay in left ventricle (LV), lungs, diaphragm, gastrocnemius and soleus in rats with CHF. Methods: Twelve male Wistar rats (300 to 330 g) were selected for the study: Sham (n = 6) and CHF (n = 6). The animals underwent myocardial infarction by the ligation of the left coronary artery. After six weeks, the animals were euthanized. It was performed a cell suspension of the tissues. The comet assay was performed to evaluate single and double strand breaks in DNA. Significance level (p) considered < 0.05. Results: The CHF group showed higher values of left ventricle end-diastolic pressure (LVEDP), pulmonary congestion, cardiac hypertrophy and lower values of maximal positive and negative derivatives of LV pressure, LV systolic pressure (p < 0.05). CHF group showed higher DNA damage (% tail DNA, tail moment and Olive tail moment) compared to Sham (p < 0.001). The tissue with the highest damage was the soleus, compared to LV and gastrocnemius in CHF group (p < 0.05). Conclusion: Our results indicates that the CHF affects all tissues, both centrally and peripherically, being more affected in skeletal muscle (soleus) and is positively correlated with LV dysfunction.

Resumo Fundamento: A insuficiência cardíaca crônica (ICC) é uma síndrome complexa que compreende alterações estruturais e funcionais no coração, mantendo demanda sanguínea adequada a todos os tecidos. Poucas investigações procuraram avaliar o dano oxidativo ao DNA na ICC. Objetivo: Quantificar o dano ao DNA utilizando o ensaio cometa no ventrículo esquerdo (VE), pulmões, diafragma, gastrocnêmio e sóleo em ratos com ICC. Métodos: Doze ratos Wistar machos (300 a 330 g) foram selecionados para o estudo: placebo (n = 6) e ICC (n = 6). Os animais foram submetidos a infarto do miocárdio através de ligadura da artéria coronária esquerda. Após seis semanas, os animais foram sacrificados. Foi realizada uma suspensão celular dos tecidos. O ensaio cometa foi realizado para avaliar as quebras de fita simples e dupla no DNA. Nível de significância (p) < 0,05. Resultados: O grupo ICC apresentou maiores valores de pressão diastólica final do ventrículo esquerdo (PDFVE), congestão pulmonar, hipertrofia cardíaca e menores valores de derivados máximos positivos e negativos da pressão do VE, pressão sistólica do VE (p < 0,05). O grupo ICC apresentou maior dano ao DNA (% de DNA da cauda, momento da cauda e momento da cauda de Olive) em comparação ao placebo (p < 0,001). O tecido com maior dano foi o sóleo, comparado ao VE e ao gastrocnêmio no grupo ICC (p < 0,05). Conclusão: Nossos resultados indicam que a ICC afeta todos os tecidos, de maneira central e periférica, sendo mais afetada no músculo esquelético (sóleo) e está positivamente correlacionada com a disfunção do VE.

Effects of creatine supplementation associated with resistance training on oxidative stress in different tissues of rats.

BACKGROUND: Creatine supplementation is known to exert an effect by increasing strength in high intensity and short duration exercises. There is a hypothesis which suggests that creatine supplementation may provide antioxidant activity by scavenging Reactive Oxygen Species. However, the antioxidant effect of creatine supplementation associated with resistance training has not yet been described in the literature. Therefore, we investigated the effect of creatine monohydrate supplementation associated with resistance training over maximum strength gain and oxidative stress in rats. METHODS: Forty male Wistar rats (250-300 g, 90 days old) were randomly allocated into 4 groups: Sedentary (SED, n = 10), Sedentary + Creatine (SED-Cr, n = 10), Resistance Training (RT, n = 10) and Resistance Training + Creatine (RT-Cr, n = 10). Trained animals were submitted to the RT protocol (4 series of 10-12 repetitions, 90 second interval, 4 times per week, 65% to 75% of 1MR, for 8 weeks). RESULTS: In this study, greater strength gain was observed in the SED-Cr, RT and RT-Cr groups compared to the SED group (P < 0.001). The RT-Cr group showed a higher maximum strength gain when compared to other groups (P < 0.001). Creatine supplementation associated with resistance training was able to reduce lipoperoxidation in the plasma (P < 0.05), the heart (P < 0.05), the liver (P < 0.05) and the gastrocnemius (P < 0.05) when compared to control groups. However, the supplementation had no influence on catalase activity (CAT) in the analyzed organs. Only in the heart was the CAT activity higher in the RT-Cr group (P < 0.05). The activity of superoxide dismutase (SOD) was lower in all of the analyzed organs in the SED-Cr group (P < 0.05), while SOD activity was lower in the trained group and sedentary supplemented group (P < 0.05). CONCLUSIONS: Creatine was shown to be an effective non-enzymatic antioxidant with supplementation alone and also when it was associated with resistance training in rats.