The impact of aerobic and anaerobic training regimes on blood pressure in normotensive and hypertensive rats: focus on redox changes

Moderate intensity continuous versus high intensity interval training: Metabolic responses of slow and fast skeletal muscles in rat

The healthy benefits of regular physical exercise are mainly mediated by the stimulation of oxidative and antioxidant capacities in skeletal muscle. Our understanding of the cellular and molecular responses involved in these processes remain often uncomplete particularly regarding muscle typology. The main aim of the present study was to compare the effects of two types of exercise training protocol: a moderate-intensity continuous training (MICT) and a high-intensity interval training (HIIT) on metabolic processes in two muscles with different typologies: soleus and extensor digitorum longus (EDL). Training effects in male Wistar rats were studied from whole organism level (maximal aerobic speed, morphometric and systemic parameters) to muscle level (transcripts, protein contents and enzymatic activities involved in antioxidant defences, aerobic and anaerobic metabolisms). Wistar rats were randomly divided into three groups: untrained (UNTR), n = 7; MICT, n = 8; and HIIT, n = 8. Rats of the MICT and HIIT groups ran five times a week for six weeks at moderate and high intensity, respectively. HIIT improved more than MICT the endurance performance (a trend to increased maximal aerobic speed, p = 0.07) and oxidative capacities in both muscles, as determined through protein and transcript assays (AMPK-PGC-1α signalling pathway, antioxidant defences, mitochondrial functioning and dynamics). Whatever the training protocol, the genes involved in these processes were largely more significantly upregulated in soleus (slow-twitch fibres) than in EDL (fast-twitch fibres). Solely on the basis of the transcript changes, we conclude that the training protocols tested here lead to specific muscular responses.

The high-intensity interval training mitigates the cardiac remodeling in spontaneously hypertensive rats

AIM

To evaluate the influence of high-intensity interval training (HIIT) on cardiac structural and functional characteristics and myocardial mitogen-activated protein kinase (MAPK) signaling in hypertensive rats.

METHODS

Male rats (12 months old) were divided into three groups: Wistar Kyoto rats (WKY, n = 8); sedentary spontaneously hypertensive rats (SED-SHR, n = 10), and trained spontaneously hypertensive rats (HIIT-SHR, n = 10). Systolic blood pressure (SBP), functional capacity, echocardiography, isolated papillary muscle, and gene expression of MAPK gene-encoding proteins associated with Elk1, cJun, ATF2, MEF2 were analyzed.

KEY FINDINGS

HIIT decreased SBP and increased functional capacity, left ventricular diastolic diameter, posterior wall thickness-left ventricle, relative wall thickness-left ventricle, and resting tension of the papillary muscle. In hypertensive rats, we observed a decrease in the gene-encoding ATF2 protein; this decrease was reversed by HIIT.

SIGNIFICANCE

The influence of HIIT in the SHR model in the compensated hypertension phase generated an increase in cardiac hypertrophy, attenuated myocardial diastolic dysfunction, lowered blood pressure, improved functional capacity, and reversed the alteration in gene-encoding ATF2 protein.

High-intensity interval training attenuates the effects caused by arterial hypertension in the ventral prostate

BACKGROUND

The prostatic effects induced by arterial hypertension is very controversial and its mechanism is unclear. High-intensity interval training (HIIT) is an exercise considered to be hypotensive. The objective of this work was to investigate the molecular, biochemical, and morphological effects of 8 weeks of HIIT in the prostatic tissue of spontaneously hypertensive rats (SHR).

METHODS

Twenty male SHR rats, 51.4 weeks old, were used. The SHR animals were divided into two groups: spontaneously sedentary hypertensive and spontaneously hypertensive submitted to HIIT. We analyze androgens receptor and glucocorticoid receptors in the prostate. Still, we verify effects of the hypertension and HIIT on the physiopathology prostatic, for immunohistochemistry investigated BCL-2, BAX, IGF-1, FAS/CD95, data's inflammatory tumour necrosis factor α, nuclear factor kappa B and interleukin (IL)-6, anti-inflammatory IL-10. The echocardiographic evaluation was performed at the baseline and after the training period.

RESULTS

Arterial hypertension promote high prostatic intraepithelial neoplasia incidence in the prostate, increases IGF-1, BCL-2 (p < 0.05), and inflammatory proteins (p < 0.05). Eight weeks of HIIT training reduced the arterial pressure and increase the concentration of tissue collagen and intracellular glycogen and showed a higher expression of BAX, FAS/CD95, and IL-10 proteins (p < 0.05), coinciding with a lower incidence of lesions and lower prostate weight (p < 0.05) and reduction of the BCL-2 and IGF-1.

CONCLUSION

Our data suggested that arterial hypertension suppressed apoptosis and increased damage prostatic. On other hand, HIIT promotes morphology and function improves in the prostatic environment, inhibited inflammation, and increased apoptosis.

Cardiovascular Properties of the Androgen-Induced PCOS Model in Rats: The Role of Oxidative Stress

Polycystic ovary syndrome (PCOS) is a multifaced reproductive endocrinopathy affecting 6-20% of women of childbearing age. It was previously shown that women with PCOS have an increased risk of cardiovascular (CV) diseases. The aim of this study was to evaluate the cardiodynamic parameters of isolated rats' hearts, blood pressure levels, and histomorphological changes in the heart tissue following the androgen-induced PCOS model in rats and the role of oxidative stress in the development of these CV properties of PCOS. 21-day-old female rats (n = 12) were divided into control and PCOS groups. PCOS was induced by administration of testosterone enanthate (1 mg/kg BW, daily) during 35 days. During the autoregulation protocol (40-120 mmHg) on the Langendorff apparatus, ex vivo cardiodynamic parameters of retrogradely perfused hearts showed enhanced contractile function and increased lusitropic effects in the left ventricle (LV) in PCOS rats. Systolic and diastolic pressures in LV were elevated at all perfusion pressure values. Systemic arterial systolic blood pressure showed borderline elevation, while mean arterial blood pressure was significantly higher in PCOS rats. Histological evaluation of heart tissue depicted hypertrophic (8.3%) alterations in LV cardiomyocytes and increase (7.3%) in LV wall thickness. Oxidative stress parameters were altered in systemic circulation, coronary venous effluent (CVE), and heart tissue. Levels of superoxide dismutase and reduced glutathione were decreased in blood and heart tissue, while catalase activity was not altered. Degree of lipid peroxidation was increased in circulation as well as heart tissue. Increased levels of O₂⁻ in CVE indicated the cardiotoxic effects in the rat PCOS model. The mentioned alterations of oxidative stress parameters in the blood, CVE, and heart could be recommended as potential contributors underlying the development of CV risk in PCOS women.

SWIM TRAINING REVERSES SOME EFFECTS OF NANDROLONE DECANOATE IN WISTAR RATS

ABSTRACT Introduction: The indiscriminate use of androgenic steroids may have deleterious effects on human tissue. Objectives: Evaluate the effects of chronic administration of the steroid nandrolone decanoate (DECA) on autonomic cardiovascular modulation, kidney morphometry and the association between these variables in Wistar rats subjected to physical training with swimming. Methods: Thirty-two male Wistar rats aged 20 weeks were distributed among four experimental groups according to the training received: sedentary control (SC), sedentary treated with DECA (SD), trained control (TC) and trained treated with DECA (TD). The hemodynamic parameters, including blood pressure and variations in systolic blood pressure (SBPV) and diastolic blood pressure (DBPV), and kidney morphometry were evaluated. The level of significance adopted was 5%. Results: The SD group had higher baseline SBP and DBP values when compared to the SC, TC and TD groups, which were similar to each other. The rats in the SD group had higher systolic blood pressure (SBPV) and diastolic blood pressure (DBPV) variation values and higher absolute and normalized values in the LF band of the DBPV when compared to the animals in the SC, TC and TD groups. The animals in the SD group had a significantly higher rate of kidney fibrosis compared to the SC, TC and TD groups. There were no significant differences between the sympathetic modulation of SBPV through the LF component and kidney fibrosis. Conclusions: Physical training with swimming was effective in preventing the increase in blood pressure levels and lowering the occurrence of kidney fibrosis in animals treated with anabolic steroids. Level of Evidence IV; Series of cases .

The Effect of Short-Term Wingate-Based High Intensity Interval Training on Anaerobic Power and Isokinetic Muscle Function in Adolescent Badminton Players

Badminton requires both aerobic fitness and anaerobic ability for high performance. High intensity interval training (HIIT) is a traditional training method for improving fitness. In this study, we investigated whether short-term Wingate-based HIIT is effective for improving anaerobic activity in youth badminton players. Participants included 32 total badminton players in middle school and high school. They were divided into two groups (HIIT and moderate continuous training (MCT)). Training occurred for 4 weeks in total, three times a week, for 30 min each session. A body composition test, isokinetic knee muscle function test (60°/s, 240°/s), Wingate anaerobic power test (30 s × 5 sets), and analysis of heart rate changes were undertaken before and after training. After 4 weeks, body fat decreased in the HIIT group (p = 0.019); they also showed superior anaerobic ability compared to the MCT group. Differences were statistically significant in 3-4 sets (three sets, p = 0.019; four sets, p = 0.021). Regarding fatigue, the HIIT group showed superior fatigue improvement after training and better fatigue recovery ability in 3~5 sets (three sets, p = 0.032; four sets, p = 0.017; five sets, p = 0.003) than the MCT group. Neither group exhibited changes in heart rate during the anaerobic power test after training. Both groups improved in terms of isokinetic knee muscle function at 60°/s with no differences. However, at 240°/s, the HIIT group showed a statistically significant improvement (p = 0.035). Therefore, HIIT for 4 weeks improved the athletes' performance and physical strength.

Effect of treatment with carvacrol and aerobic training on cardiovascular function in spontaneously hypertensive rats

NEW FINDINGS

What is the central question of this study? Can two non-drug therapies, carvacrol and aerobic physical training, together have additive effects on the reduction of cardiovascular risks and control of arterial hypertension? What is the main finding and its importance? The oral use of carvacrol (20 mg/kg/day) can control sustained hypertension in spontaneously hypertensive rats, and when this use is associated with aerobic physical training, there is a more pronounced effect on the reduction of blood pressure values, making these therapies an adjunct option in the drug treatment of hypertension.

ABSTRACT

Systemic arterial hypertension is considered the foremost cardiovascular risk factor, and it is important to examine different therapies that help prevent and treat it, especially when associated with other cardiovascular risk factors. In this context, it is known that both carvacrol and aerobic physical training benefit the cardiovascular system. This study investigated the effects of treatment with carvacrol combined with aerobic exercise on hypertensive rats with cardiovascular risk parameters. We used an experimental design with six groups: normotensive control (Wistar rats); hypertensive control (spontaneously hypertensive rats, SHR); positive control rats treated with amlodipine (Aml-20 mg); rats treated with carvacrol (Carv-20 mg); rats trained with exercise (Exer); and rats treated with carvacrol and exercise (ExerCarv). The treatment lasted for 4 weeks, monitoring heart rate and systolic blood pressure (SBP). At the end of the treatment, vascular reactivity tests were performed in addition to biochemical measurements of urea, creatinine, aspartate aminotransferase, alanine aminotransferase, triglycerides, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, very low density lipoprotein cholesterol, atherogenic indexes, relative heart weight and histopathological analysis of cardiac perivascular tissue. Significant reductions in SBP were observed after the training period, with the ExerCarv group showing a greater magnitude of reduction (∆SBP = 88 ± 10.0 mmHg, 42%). This group also experienced reductions in atherogenic indices and improvement in all analysed lipid parameters, with no differences observed in the Exer group. The findings indicated that the interaction between aerobic exercise and carvacrol offers a greater BP reduction. Exercise is particularly effective for controlling biochemical parameters of cardiovascular risk, regardless of carvacrol use.

The Interplay between Oxidative Stress, Exercise, and Pain in Health and Disease: Potential Role of Autonomic Regulation and Epigenetic Mechanisms

Oxidative stress can be induced by various stimuli and altered in certain conditions, including exercise and pain. Although many studies have investigated oxidative stress in relation to either exercise or pain, the literature presents conflicting results. Therefore, this review critically discusses existing literature about this topic, aiming to provide a clear overview of known interactions between oxidative stress, exercise, and pain in healthy people as well as in people with chronic pain, and to highlight possible confounding factors to keep in mind when reflecting on these interactions. In addition, autonomic regulation and epigenetic mechanisms are proposed as potential mechanisms of action underlying the interplay between oxidative stress, exercise, and pain. This review highlights that the relation between oxidative stress, exercise, and pain is poorly understood and not straightforward, as it is dependent on the characteristics of exercise, but also on which population is investigated. To be able to compare studies on this topic, strict guidelines should be developed to limit the effect of several confounding factors. This way, the true interplay between oxidative stress, exercise, and pain, and the underlying mechanisms of action can be revealed and validated via independent studies.

Preconditioning with PDE1 Inhibitors and Moderate-Intensity Training Positively Affect Systemic Redox State of Rats

Taken into consideration that oxidative stress response after preconditioning with phosphodiesterase inhibitors (PDEIs) and moderate physical activity has still not been clarified, the aim of this study was to assess the effects of PDEIs alone or in combination with physical activity, on systemic redox status. The study was carried out on 96 male Wistar albino rats classified into two groups. The first group included animals exposed only to pharmacological preconditioning (PreC) maneuver (sedentary control (CTRL, 1 ml/day saline, n = 12), nicardipine (6 mg/kg/day of NIC, n = 12), vinpocetine (10 mg/kg/day of VIN, n = 12), and nimodipine (NIM 10 mg/kg/day of, n = 12). The second included animals exposed to preconditioning with moderate-intensity training (MIT) on treadmill for 8 weeks. After 5 weeks from the start of training, the animals were divided into four subgroups depending on the medication to be used for pharmacological PreC: moderate-intensity training (MIT+ 1 ml/day saline, n = 12), nicardipine (MIT+ 6 mg/kg/day of NIC, n = 12), vinpocetine (MIT+ 10 mg/kg/day of VIN, n = 12), and nimodipine (MIT+ 10 mg/kg/day of NIM, n = 12). After three weeks of pharmacological preconditioning, the animals were sacrificed. The following oxidative stress parameters were measured spectrophotometrically: nitrites (NO₂⁻), superoxide anion radical (O₂⁻), hydrogen peroxide (H₂O₂), index of lipid peroxidation (TBARS), superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (GSH). Our results showed that PDE1 and MIT preconditioning decreased the release of prooxidants and improved the activity of antioxidant enzymes thus preventing systemic oxidative stress.

Exercise-Induced Regulation of Redox Status in Cardiovascular Diseases: The Role of Exercise Training and Detraining

Although low levels of reactive oxygen species (ROS) are beneficial for the organism ensuring normal cell and vascular function, the overproduction of ROS and increased oxidative stress levels play a significant role in the onset and progression of cardiovascular diseases (CVDs). This paper aims at providing a thorough review of the available literature investigating the effects of acute and chronic exercise training and detraining on redox regulation, in the context of CVDs. An acute bout of either cardiovascular or resistance exercise training induces a transient oxidative stress and inflammatory response accompanied by reduced antioxidant capacity and enhanced oxidative damage. There is evidence showing that these responses to exercise are proportional to exercise intensity and inversely related to an individual’s physical conditioning status. However, when chronically performed, both types of exercise amplify the antioxidant defense mechanism, reduce oxidative stress and preserve redox status. On the other hand, detraining results in maladaptations within a time-frame that depends on the exercise training intensity and mode, as high-intensity training is superior to low-intensity and resistance training is superior to cardiovascular training in preserving exercise-induced adaptations during detraining periods. Collectively, these findings suggest that exercise training, either cardiovascular or resistance or even a combination of them, is a promising, safe and efficient tool in the prevention and treatment of CVDs.

High-intensity intermittent training is as effective as moderate continuous training, and not deleterious, in cardiomyocyte remodeling of hypertensive rats

Exercise training offers possible nonpharmacological therapy for cardiovascular diseases including hypertension. High-intensity intermittent exercise (HIIE) training has been shown to have as much or even more beneficial cardiovascular effect in patients with cardiovascular diseases than moderate-intensity continuous exercise (CMIE) training. The aim of this study was to investigate the effects of the two types of training on cardiac remodeling of spontaneously hypertensive rats (SHR) induced by hypertension. Eight-week-old male SHR and normotensive Wistar-Kyoto rats (WKY) were divided into four groups: normotensive and hypertensive control (WKY and SHR-C) and hypertensive trained with CMIE (SHR-T CMIE) or HIIE (SHR-T HIIE). After 8 wk of training or inactivity, maximal running speed (MRS), arterial pressure, and heart weight were all assessed. CMIE or HIIE protocols not only increased final MRS and left ventricular weight/body weight ratio but also reduced mean arterial pressure compared with sedentary group. Then, left ventricular tissue was enzymatically dissociated, and isolated cardiomyocytes were used to highlight the changes induced by physical activity at morphological, mechanical, and molecular levels. Both types of training induced restoration of transverse tubule regularity, decrease in spark site density, and reduction in half-relaxation time of calcium transients. HIIE training, in particular, decreased spark amplitude and width, and increased cardiomyocyte contractility and the expression of sarco(endo)plasmic reticulum Ca²⁺-ATPase and phospholamban phosphorylated on serine 16. NEW & NOTEWORTHY High-intensity intermittent exercise training induces beneficial remodeling of the left ventricular cardiomyocytes of spontaneously hypertensive rats at the morphological, mechanical, and molecular levels. Results also confirm, at the cellular level, that this type of training, as it appears not to be deleterious, could be applied in rehabilitation of hypertensive patients.