A 6-week training program increased muscle antioxidant system in elderly diabetic fatty rats

Aerobic exercise 3 times per week in adult rats did not influence the progression of periodontal disease

Introduction

Physical exercise has proven efficacy in the prevention and treatment of chronic diseases, and its anti-inflammatory effect has been evaluated as a potential preventive factor in the progression of periodontal disease, in addition to improving physiological parameters.

Methods

To test this hypothesis regarding its preventive factor, we evaluated the effects of aerobic training on the progression of periodontal disease in 8-month-old Wistar rats (n = 44). The animals underwent a swimming protocol lasting six weeks, with periodontal disease induced by ligature in the fifth week, totaling fourteen days of ligature placement. Anthropometric parameters were measured for subsequent calculations of BMI and Lee's Index. Interleukin-1β testing was performed to measure serum inflammatory parameters, and alveolar bone loss was measured using images to calculate the area of loss.

Results

The trained animals showed no significant differences compared to the non-trained animals in terms of anthropometric measures. Regarding the area of bone loss, although there were significant differences between the groups with and without periodontal disease, exercise did not demonstrate an impact on rats with the disease. IL-1β analysis did not detect any measurable values in the samples in either group.

Discussion

These findings indicate that the applied exercise protocol was not sufficient to attenuate the progression of periodontal disease. This study did not find an effective impact of physical exercise on the analyzed parameters; however, the results are important in highlighting that the experimental animal model for inducing periodontal disease is efficient, which may encourage further investigations to determine factors that can attenuate its progression. Similarly, the application or development of new exercise protocols that can benefit and enrich the discussion on its positive effects in this disease is important, as there is already evidence suggesting an effective relationship between exercise and disease progression.

Effects of Exercise Combined with Undenatured Type II Collagen on Endurance Capacity, Antioxidant Status, Muscle Lipogenic Genes and E3 Ubiquitin Ligases in Rats

The current study aimed to investigate the effect of exercise combined with undenatured type II collagen (UCII) administration on endurance capacity, lipid metabolism, inflammation, and antioxidant status in rats. Twenty-one male Wistar albino rats were divided into three groups as follows: (1) Sedentary control, (2) Exercise (E), (3) Exercise + UCII (4 mg/kg BW/day; E + UCII). The findings showed that the exhaustive running time in the UCII group was significantly prolonged compared to that of the non-supplemented group (p < 0.001). When compared to the control group, total serum cholesterol (TC, p < 0.05) and triglyceride (TG, p < 0.05) levels decreased, while creatinine kinase (CK) levels increased in the E group (p < 0.001). Serum creatinine kinase levels were reduced in the E + UCII group compared to the E group (p < 0.01). Serum lactate, myoglobin (p < 0.01), and osteocalcin levels (p < 0.01) increased significantly in exercised rats compared to sedentary control rats, while serum lactate (p < 0.01) and myoglobin (p < 0.0001) levels decreased in the E + UCII group compared to control. Additionally, UCII supplementation caused significant increases in antioxidant enzyme activities [SOD (p < 0.01) and GSH-Px (p < 0.05)] and decreases in malondialdehyde (MDA) and tumor necrosis factor (TNF-α) levels (p < 0.001). Muscle lipogenic protein (SREBP-1c, ACLY, LXR, and FAS) levels were lower in the E + UCII group than in other groups. In addition, UCII supplementation decreased muscle MAFbx, MuRF-1, myostatin and increased MyoD levels in exercised rats. Moreover, the E + UCII group had lower muscle inflammatory markers [TNF-α (p < 0.0001) and IL-1β (p < 0.01)] than the control group. These results suggest exercise combined with UCII (4 mg/kg BW/day) modulates lipid, muscle, and antioxidant status in rats.

Basic Studies on the Oxidative Stress Markers in Two Types of Horse Breed: Semi-isolated Population of Huculs Is Different from Commercially Used Arabian Horses

Hucul and Arabian horses differ in the physiological constitution and exposition to environmental conditions. Oxidative stress plays a pathogenic role in many diseases and enables further injuries. The objective of this study was to compare the levels of enzymatic and nonenzymatic oxidative stress markers in Hucul horses living in seminatural conditions and in commercially handled Arabian horses. We tested the serum samples for total superoxide dismutase (total SOD), Cu-Zn-superoxide dismutase (CuZnSOD), and Mn-dependent superoxide dismutase (MnSOD) activity; for lipofuscin (LPS), ceruloplasmin (CER) and malondialdehyde (MDA) concentration; and for total antioxidant capacity (TAC) and total oxidant status (TOS). Total SOD (p < 0.001), MnSOD (p < 0.001), and CuZnSOD (p < 0.001) activities were significantly higher whereas LPS (p < 0.05), TAC (p < 0.001), TOS (p < 0.001), and MDA (p < 0.001) concentrations were significantly lower in the serum samples collected from Huculs vs. Arabian horses, regardless of the gender. Gender, regardless of the breed, had no significant impact on the antioxidants' activity and concentration. Total SOD and MnSOD activities were significantly higher in Hucul's mares when compared to Hucul's stallions. Concentrations of TAC and TOS were significantly lower in Arabian stallions than in Arabian mares. Commercially handled horses expressed a higher level of oxidative stress markers in comparison to breeds living in seminatural conditions. We conclude that antioxidants are important biomarkers of animal health, whether they are under maintenance care or performing physical exercise.

Paracetamol-induced metabolic and cardiovascular changes are prevented by exercise training

Paracetamol (PAR) is the most frequently consumed non-prescription drug, yet it is well known to induce toxicity. Here, we have evaluated the effects of exercise training on vascular dysfunction induced by PAR. Rats were distributed among four groups: (a) Sedentary; (b) Exercise; (c) Sedentary+PAR; and (d) Exercise+PAR. The exercise comprised swimming 50 min/d, 5 d/wk for 6 weeks (+PAR in the last 2 weeks, at 400 mg/kg/d/p.o.). After killing, the rats' blood and aortas were collected for biochemical analysis of hepatic transaminases, TBARs reaction, glutathione, glutathione reductase, SOD, and catalase. In vitro vascular relaxation was measured using acetylcholine and sodium nitroprusside in the presence or absence of tiron (an antioxidant). Vascular protein expression (eNOS and sGC) also were analysed. Increased transaminases after PAR treatment were found to be reduced by exercise. Vasodilation was impaired by PAR only in the sedentary group. Exercise prevented alterations in lipoperoxidation and glutathione levels after PAR exposure. Glutaathione reductase and SOD also were increased by PAR but were normalized in the exercised group. Catalase activity and protein expressions did not change in any group. PAR treatment caused impairment in both vasodilation and redox balance; however, exercise training prevented the vascular and redox system dysfunction induced by PAR treatment.

A Dose-Dependent Effect of Carnipure® Tartrate Supplementation on Endurance Capacity, Recovery, and Body Composition in an Exercise Rat Model

The objective of this work is to investigate the effects of Carnipure^® Tartrate (CT) supplementation with or without exercise on endurance capacity, recovery, and fatigue by assessing time to exhaustion as well as body weight and composition in rats. In addition, antioxidant capacity has been evaluated by measuring malondialdehyde (MDA) levels and antioxidant enzyme (superoxide dismutase, SOD; catalase, CAT; glutathioneperoxidase; GSHPx) activities. Fifty-six male Wistar rats were divided into eight groups including seven rats each. A control group did not receive CT nor exercise. Another control group received 200 mg/kg CT without exercise. The other six groups of rats went through an exercise regimen consisting of a 5-day training period with incremental exercise capacity, which was followed by 6 weeks of the run at 25 m/min for 45 min every day. CT was supplemented at 0, 25, 50, 100, 200, and 400 mg/kg per day during the 6 weeks. Rats submitted to exercise and supplemented with CT had a significant and dose-dependent increase in time to exhaustion and this effect seems to be independent of exercise (p < 0.05). Additionally, recovery and fatigue were improved, as shown by a significant and dose-dependent decrease in myoglobin and lactic acid plasma levels, which are two markers of muscle recovery. CT supplementation led to a dose-response decrease in body weight and visceral fat. These effects become significant at 200 and 400 mg/kg doses (p < 0.05). Additionally, the antioxidant capacity was improved, as shown by a significant and dose-dependent increase in SOD, CAT, and GSHPx. Serum MDA concentrations decreased in exercising rats with CT supplementation. CT supplementation led to a decrease in serum glucose, triglycerides, and total cholesterol concentrations with the lowest levels observed at 400 mg/kg dose (p < 0.05). These effects correlated with a significant dose-dependent increase in serum total L-carnitine, free L-carnitine, and acetyl-carnitine, which linked the observed efficacy to CT supplementation. These results demonstrate that CT supplementation during exercise provides benefits on exercise performance, recovery, and fatigue as well as improved the lipid profile and antioxidant capacity. The lowest dose leads to some of these effects seen in rats where 25 mg/kg corresponds to 250 mg/day as a human equivalent.

Oxidative Stress: A Unifying Mechanism for Cell Damage Induced by Noise, (Water-Pipe) Smoking, and Emotional Stress-Therapeutic Strategies Targeting Redox Imbalance

SIGNIFICANCE

Modern technologies have eased our lives but these conveniences can impact our lifestyles in destructive ways. Noise pollution, mental stresses, and smoking (as a stress-relieving solution) are some environmental hazards that affect our well-being and healthcare budgets. Scrutinizing their pathophysiology could lead to solutions to reduce their harmful effects. Recent Advances: Oxidative stress plays an important role in initiating local and systemic inflammation after noise pollution, mental stress, and smoking. Lipid peroxidation and release of lysolipid by-products, disturbance in activation and function of nuclear factor erythroid 2-related factor 2 (Nrf2), induction of stress hormones and their secondary effects on intracellular kinases, and dysregulation of intracellular Ca²⁺ can all potentially trigger other vicious cycles. Recent clinical data suggest that boosting the antioxidant system through nonpharmacological measures, for example, lifestyle changes that include exercise have benefits that cannot easily be achieved with pharmacological interventions alone.

CRITICAL ISSUES

Indiscriminate manipulation of the cellular redox network could lead to a new series of ailments. An ideal approach requires meticulous scrutiny of redox balance mechanisms for individual pathologies so as to create new treatment strategies that target key pathways while minimizing side effects.

FUTURE DIRECTIONS

Extrapolating our understanding of redox balance to other debilitating conditions such as diabetes and the metabolic syndrome could potentially lead to devising a unifying therapeutic strategy. Antioxid. Redox Signal. 28, 741-759.

Effects of different aerobic exercise frequencies on streptozotocin-nicotinamide-induced type 2 diabetic rats: Continuous versus short bouts and weekend warrior exercises

BACKGROUND

Exercise training is known to have multiple beneficial effects on type 2 diabetes mellitus (T2DM). The aim of this study was to explore the effects of aerobic exercise frequency on diabetic parameters, the histopathological structure of skeletal muscle, diabetic myopathy, and mitochondrial enzyme activity in an experimental model of T2DM.

METHODS

Sprague-Dawley rats (n = 35) were rendered diabetic by injection of nicotinamide (110 mg/kg) and streptozotocin (65 mg/kg). Rats with blood glucose concentrations between 7 and 17 mmol/L were used. Diabetic rats were randomly allocated to one of the following groups: (i) control sedentary; (ii) diabetic sedentary; (iii) diabetic with continuous exercise (30 min/day, 5 days/week); (iv) diabetic with short bouts of exercise (3 × 10 min/day, 5 days/week); and (v) diabetic rats as "weekend warriors" (35 + 40 min/day, 2 days/week). After 6 weeks swimming exercise (total duration 150 min/week), biochemical tests were performed to measure insulin, glucose, cytokines, serum and muscle myeloperoxidase (MPO), and malondialdehyde (MDA) levels. Histologic analysis (histomorphometric and mitochondrial enzyme analysis) was also performed.

RESULTS

Compared with diabetic sedentary rats, significant improvements were observed in all exercise groups in terms of glucose levels, weight loss, tissue MPO and MDA levels, muscular connective tissue, muscle atrophy, mitochondrial enzyme, and all histomorphometric analyses.

CONCLUSIONS

The results of the study emphasize the effects of training on inflammation, increased oxidative stress, myopathy, and mitochondrial damage in a rat model of T2DM, and demonstrate that there is no major difference between exercise modalities provided that the total duration of exercise remains the same.

l-Arginine supplementation improves rats' antioxidant system and exercise performance

Reactive species have great importance in sports performance, once they can directly regulate energy production, muscular contraction, inflammation, and fatigue. Therefore, the redox control is essential for athletes' performance. Studies demonstrated that l-arginine has an important role in the synthesis of urea, cell growth and production of nitric oxide, moreover, there are indications that it is also able to induce benefits to muscle antioxidant system through the upregulation of some antioxidant enzymes, and by inhibiting some pathways of reactive species production. Therefore, the aim of this study was to evaluate the effects of l-arginine supplementation on performance and oxidative stress of male rats (trained or not), submitted to a single session of high intensity exercise. Forty male Wistar rats were divided into four groups, control (C), control+l-arginine (C + A), trained (T), and trained+l-arginine (T + A). The aerobic training was conducted for 8 weeks. Data of maximum speed and time from tests were used as indicators of performance. Variables related to oxidative stress and antioxidant system were also evaluated. Aerobic training was capable to induce enhancements on animals' exercise performance and on their redox state. Additionally, supplementation improved rats' physical performance on both groups, control and trained. Different improvements between groups on the antioxidant capacity were observed. Nevertheless, considering the ergogenic effect of l-arginine and the lack of all positive adaptations promoted by the exercise training, untrained animals may be more exposed to oxidative damages after the practice of intense exercises.

Exercise Modulates Oxidative Stress and Inflammation in Aging and Cardiovascular Diseases

Despite the wealth of epidemiological and experimental studies indicating the protective role of regular physical activity/exercise training against the sequels of aging and cardiovascular diseases, the molecular transducers of exercise/physical activity benefits are not fully identified but should be further investigated in more integrative and innovative approaches, as they bear the potential for transformative discoveries of novel therapeutic targets. As aging and cardiovascular diseases are associated with a chronic state of oxidative stress and inflammation mediated via complex and interconnected pathways, we will focus in this review on the antioxidant and anti-inflammatory actions of exercise, mainly exerted on adipose tissue, skeletal muscles, immune system, and cardiovascular system by modulating anti-inflammatory/proinflammatory cytokines profile, redox-sensitive transcription factors such as nuclear factor kappa B, activator protein-1, and peroxisome proliferator-activated receptor gamma coactivator 1-alpha, antioxidant and prooxidant enzymes, and repair proteins such as heat shock proteins, proteasome complex, oxoguanine DNA glycosylase, uracil DNA glycosylase, and telomerase. It is important to note that the effects of exercise vary depending on the type, intensity, frequency, and duration of exercise as well as on the individual's characteristics; therefore, the development of personalized exercise programs is essential.

Aerobic interval exercise improves parameters of nonalcoholic fatty liver disease (NAFLD) and other alterations of metabolic syndrome in obese Zucker rats

Metabolic syndrome (MS) is a group of metabolic alterations that increase the susceptibility to cardiovascular disease and type 2 diabetes. Nonalcoholic fatty liver disease has been described as the liver manifestation of MS. We aimed to test the beneficial effects of an aerobic interval training (AIT) protocol on different biochemical, microscopic, and functional liver alterations related to the MS in the experimental model of obese Zucker rat. Two groups of lean and obese animals (6 weeks old) followed a protocol of AIT (4 min at 65%-80% of maximal oxygen uptake, followed by 3 min at 50%-65% of maximal oxygen uptake for 45-60 min, 5 days/week, 8 weeks of experimental period), whereas 2 control groups remained sedentary. Obese rats had higher food intake and body weight (P < 0.0001) and suffered significant alterations in plasma lipid profile, area under the curve after oral glucose overload (P < 0.0001), liver histology and functionality, and antioxidant status. The AIT protocol reduced the severity of alterations related to glucose and lipid metabolism and increased the liver protein expression of PPARγ, as well as the gene expression of glutathione peroxidase 4 (P < 0.001). The training protocol also showed significant effects on the activity of hepatic antioxidant enzymes, although this action was greatly influenced by rat phenotype. The present data suggest that AIT protocol is a feasible strategy to improve some of the plasma and liver alterations featured by the MS.

Influence of aerobic training on the reduced vasoconstriction to angiotensin II in rats exposed to intrauterine growth restriction: possible role of oxidative stress and AT2 receptor of angiotensin II

Intrauterine growth restriction (IUGR) is associated with impaired vascular function, which contributes to the increased incidence of chronic disease. The aim of this study was to investigate whether aerobic training improves AngII-induced vasoconstriction in IUGR rats. Moreover, we assess the role of superoxide dismutase (SOD) isoforms and NADPH oxidase-derived superoxide anions in this improvement. Female Wistar rats were randomly divided into two groups on day 1 of pregnancy. A control group was fed standard chow ad libitum, and a restricted group was fed 50% of the ad libitum intake throughout gestation. At 8 weeks of age, male offspring from both groups were randomly assigned to 4 experimental groups: sedentary control (SC), trained control (TC), sedentary restricted (SRT), and trained restricted (TRT). The training protocol was performed on a treadmill and consisted of a continuous 60-min session 5 days/week for 10 weeks. Following aerobic training, concentration–response curves to AngII were obtained in endothelium-intact aortic rings. Protein expression of SOD isoforms, AngII receptors and the NADPH oxidase component p47^phox was assessed by Western blot analysis. The dihydroethidium was used to evaluate the in situ superoxide levels under basal conditions or in the presence of apocynin, losartan or PD 123,319. Our results indicate that aerobic training can prevent IUGR-associated increases in AngII-dependent vasoconstriction and can restore basal superoxide levels in the aortic rings of TRT rats. Moreover, we observed that aerobic training normalized the increased p47^phox protein expression and increased MnSOD and AT₂ receptor protein expression in thoracic aortas of SRT rats. In summary, aerobic training can result in an upregulation of antioxidant defense by improved of MnSOD expression and attenuation of NADPH oxidase component p47^phox. These effects are accompanied by increased expression of AT₂ receptor, which provide positive effects against Ang II–induced superoxide generation, resulting in attenuation of AngII-induced vasoconstriction.