RESUMO
Our purpose was to characterize the oxygen uptake kinetics (VO2), energy systems contributions and total energy expenditure during a CrossFit® benchmark workout performed in the extreme intensity domain. Fourteen highly trained male CrossFitters, aged 28.3 ± 5.4 years, with height 177.8 ± 9.4 cm, body mass 87.9 ± 10.5 kg and 5.6 ± 1.8 years of training experience, performed the Isabel workout at maximal exertion. Cardiorespiratory variables were measured at baseline, during exercise and the recovery period, with blood lactate and glucose concentrations, including the ratings of perceived exertion, measured pre- and post-workout. The Isabel workout was 117 ± 10 s in duration and the VO2 peak was 47.2 ± 4.7 mL·kg-1·min-1, the primary component amplitude was 42.0 ± 6.0 mL·kg-1·min-1, the time delay was 4.3 ± 2.2 s and the time constant was 14.2 ± 6.0 s. The accumulated VO2 (0.6 ± 0.1 vs. 4.8 ± 1.0 L·min-1) value post-workout increased substantially when compared to baseline. Oxidative phosphorylation (40%), glycolytic (45%) and phosphagen (15%) pathways contributed to the 245 ± 25 kJ total energy expenditure. Despite the short ~2 min duration of the Isabel workout, the oxygen-dependent and oxygen-independent metabolism energy contributions to the total metabolic energy release were similar. The CrossFit® Isabel requires maximal effort and the pattern of physiological demands identifies this as a highly intensive and effective workout for developing fitness and conditioning for sports.
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Benchmarking , Metabolismo Energético , Masculino , Humanos , Cinética , Exercício Físico , OxigênioRESUMO
Breast cancer (BC) stands out as the most commonly type of cancer diagnosed in women worldwide, and chemotherapy, a key component of treatment, exacerbates cancer-induced skeletal muscle wasting, contributing to adverse health outcomes. Notably, the impact of chemotherapy on skeletal muscle seems to surpass that of the cancer itself, with inflammation identified as a common trigger for muscle wasting in both contexts. In skeletal muscle, pro-inflammatory cytokines modulate pathways crucial for the delicate balance between protein synthesis and breakdown, as well as satellite cell activation and myonuclear accretion. Physical exercise consistently emerges as a crucial therapeutic strategy to counteract cancer and chemotherapy-induced muscle wasting, ultimately enhancing patients' quality of life. However, a "one size fits all" approach does not apply to the prescription of exercise for BC patients, with factors such as age, menopause and comorbidities influencing the response to exercise. Hence, tailored exercise regimens, considering factors such as duration, frequency, intensity, and type, are essential to maximize efficacy in mitigating muscle wasting and improving disease outcomes. Despite the well-established anti-inflammatory role of aerobic exercise, resistance exercise proves equally or more beneficial in terms of mass and strength gain, as well as enhancing quality of life. This review comprehensively explores the molecular pathways affected by distinct exercise regimens in the skeletal muscle of cancer patients during chemotherapy, providing critical insights for precise exercise implementation to prevent skeletal muscle wasting.
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Neoplasias da Mama , Exercício Físico , Músculo Esquelético , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Feminino , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Qualidade de Vida , Terapia por Exercício/métodos , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismoRESUMO
Heart failure with preserved ejection fraction (HFpEF) is currently lacking an effective pharmacological treatment with impact on major outcomes such as hospitalization and mortality. Exercise training (EXT) is recognized as an important nonpharmacological tool, capable of improving exercise capacity and quality of life, and has even been associated with a reduction in hospitalization and cardiovascular mortality risk. However, this positive impact largely lacks a physiological explanation. The aim of this narrative review was to provide an overview of the available data supporting the hypothesis that the beneficial role of EXT in HFpEF might be due to its effects on targeting the inflammatory paradigm described for this disease. A comprehensive literature search was conducted using the PubMed-NCBI database. We reviewed the effects of EXT throughout each step of the pathophysiological pathway leading to HFpEF and found clinical and/or preclinical evidence supporting the reduction of systemic inflammation, endothelial dysfunction, microvascular rarefaction, and myocardial stiffness. We also highlighted some gaps in the knowledge or topics that deserve further clarification in future studies. In conclusion, despite the scarcity of clinical studies in this population, there is compelling evidence suggesting that EXT modulates crucial aspects of the inflammatory pathway described for HFpEF and future investigation on cellular and molecular mechanisms are encouraged.
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Insuficiência Cardíaca , Exercício Físico , Tolerância ao Exercício , Insuficiência Cardíaca/terapia , Humanos , Qualidade de Vida , Volume SistólicoRESUMO
Conventional treatments for heart failure have failed to improve survival in heart failure with preserved ejection fraction (HFpEF). The current therapy recommendations highlight the importance of symptom management and improvement of patient's well-being or other health-related outcomes. Physical activity/exercise training might be an adjuvant treatment option, since several studies in HFpEF patients reported beneficial effects on exercise intolerance, which is the main symptom associated with this disease. In addition, exercise training was shown to improve quality of life and, in some studies, to improve cardiac function. However, the mechanisms behind these effects are not completely known. The objective of this narrative review is to summarize the main clinical findings regarding the role of physical activity/exercise training in several outcomes, such as hospitalization and mortality, exercise capacity, quality of life, and cardiac function and remodeling. In addition, we will briefly discuss the findings provided by pre-clinical studies. In conclusion, while the impact of physical activity/exercise training on exercise intolerance and quality of life is already well known, its effect on mortality and hospitalization is not well documented, and whether it benefits diastolic function needs further investigation. Some clinical studies showed that exercise training can improve diastolic function, and evidences from pre-clinical studies suggest that this effect is mediated through reduced myocardial stiffness.
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Insuficiência Cardíaca , Exercício Físico , Tolerância ao Exercício , Insuficiência Cardíaca/terapia , Humanos , Qualidade de Vida , Volume SistólicoRESUMO
Exercise training provides several cardiovascular benefits in both physiological and pathological conditions; however, its use as a therapeutic tool for pulmonary arterial hypertension (PAH) has been poorly explored. This study aimed to extend the comprehension of the cardioprotective effects of exercise training in the set of PAH focusing on the metabolic changes promoted by exercise in the right ventricle (RV). The monocrotaline animal model of PAH was used and male Wistar rats were submitted to two weeks of treadmill exercise training (5 days/week, 60 min/day, 25 m/min) following disease establishment. Trained rats showed an improved diastolic function (lower end-diastolic pressure and tau) despite the presence of cardiac overload (increased peak systolic pressure, end-diastolic pressure and arterial elastance). This enhanced hemodynamic response was paralleled by an increased uptake of glucose to cardiomyocytes through glucose transporter type 4 (GLUT4) followed by increased lactate dehydrogenase (LDH) activity. Exercise did not reverse the decrease of fatty acid oxidation related to PAH but increased the content of the transcription factors peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) and peroxisome proliferator-activated receptor gamma (PPAR-γ). Two weeks of exercise did not modulate the changes in amino acid metabolism secondary to PAH. Our work suggests that continuous aerobic exercise of moderate intensity, despite its short-term duration and application in a late stage of the disease, supports the RV response to PAH by promoting a shift in the cardiac metabolic phenotype.
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Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Masculino , Ratos , Animais , Monocrotalina/efeitos adversos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Hipertensão Pulmonar/terapia , Hipertensão Pulmonar/patologia , PPAR gama/metabolismo , Transportador de Glucose Tipo 4 , Ratos Wistar , Modelos Animais de Doenças , Glucose , Lactato Desidrogenases/metabolismo , Aminoácidos , Ácidos GraxosRESUMO
BACKGROUND: Inflammation is widely recognized as the driving force of cachexia induced by chronic diseases; however, therapies targeting inflammation do not always reverse cachexia. Thus, whether inflammation per se plays an important role in the clinical course of cachectic patients is still a matter of debate. AIMS: To give new insights into cachexia's pathogenesis and diagnosis, we performed a comprehensive literature search on the contribution of inflammatory markers to this syndrome, focusing on the noncommunicable diseases cancer and cardiovascular diseases. METHODS: A systematic review was performed in PubMed using the keywords ("cancer" OR "cardiac" cachexia AND "human" OR "patient" AND "plasma" or "serum"). A total of 744 studies were retrieved and, from these, 206 were selected for full-text screening. In the end, 98 papers focusing on circulating biomarkers of cachexia were identified, which resulted in a list of 113 different mediators. RESULTS: Data collected from the literature highlight the contribution of interleukin-6 (IL-6) and C-reactive protein (CRP) to cachexia, independently of the underlying condition. Despite not being specific, once the diagnosis of cachexia is established, CRP might help to monitor the effectiveness of anti-cachexia therapies. In cardiac diseases, B-type natriuretic peptide (BNP), renin, and obestatin might be putative markers of body wasting, whereas in cancer, growth differentiation factor (GDF) 15, transforming growth factor (TGF)-ß1 and vascular endothelial growth factor (VEGF) C seem to be better markers of this syndrome. Independently of the circulating mediators, NF-κB and JAK/STAT signaling pathways play a key role in bridging inflammation with muscle wasting; however, therapies targeting these pathways were not proven effective for all cachectic patients. CONCLUSION: The critical and integrative analysis performed herein will certainly feed future research focused on the better comprehension of cachexia pathogenesis toward the improvement of its diagnosis and the development of personalized therapies targeting specific cachexia phenotypes.
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Mediadores da Inflamação , Neoplasias , Biomarcadores , Proteína C-Reativa/metabolismo , Caquexia/etiologia , Caquexia/metabolismo , Caquexia/patologia , Humanos , Inflamação/metabolismo , Neoplasias/patologia , Fator A de Crescimento do Endotélio VascularRESUMO
NEW FINDINGS: What is the central question of this study? Right ventricle (RV) dysfunction is highly prevalent in heart failure with preserved ejection fraction (HFpEF), nearly doubling the risk of death: what are the RV functional and structural changes in HFpEF and how does aerobic exercise impact them? What is the main finding and its importance? The HFpEF ZSF1 rat model presents RV structural and functional changes mimicking the human condition. Aerobic exercise prevented the decline in VÌO2max , lowered surrogate markers of RV overload (e.g., higher mean and maximum systolic pressure) and improved diastolic dysfunction (e.g., end-diastolic pressure and relaxation time constant). This emphasizes the importance of using exercise to manage HFpEF. ABSTRACT: Right ventricle (RV) dysfunction is highly prevalent in heart failure with preserved ejection fraction (HFpEF) and is a marker of poor prognosis. We assessed the obese ZSF1 rat model of HFpEF to ascertain if these animals also develop RV dysfunction and evaluated whether aerobic exercise could prevent this. Obese ZSF1 rats were randomly allocated to an aerobic exercise training group (n = 7; treadmill running, 5 days/week, 60 min/day, 15 m/min for 5 weeks) or to a sedentary group (n = 7). We used lean ZSF1 rats (n = 7) as the control group. After 5 weeks, rats were submitted to an exercise tolerance test and invasive haemodynamic evaluation, killed and samples from the RV collected for histological analysis. Obese sedentary ZSF1 rats showed lower VÌO2max , RV pressure overload (e.g., higher mean and maximum systolic pressure) and diastolic dysfunction (e.g., higher minimum and end-diastolic pressure and relaxation time constant), paralleled by RV cardiomyocyte hypertrophy. Except for cardiomyocyte hypertrophy, aerobic exercise prevented these functional changes. Our data support that this model of HFpEF shows functional and structural changes in the RV that resemble the human HFpEF phenotype, reinforcing its utility to understand this pathophysiology and to adress novel therapeutic targets to manage HFpEF. In addition, we showed that aerobic exercise is cardioprotective for the RV. A deeper knowledge of the mechanisms underlying the benefits of aerobic exercise could also lead to the identification of therapeutic targets to be further explored.
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Insuficiência Cardíaca , Animais , Diástole/fisiologia , Ventrículos do Coração , Hemodinâmica , Ratos , Volume Sistólico/fisiologiaRESUMO
NEW FINDINGS: What is the central question of this study? Does the consumption of a moderate amount of alcohol differentially impact the heart ventricles and pulmonary vasculature. What is the main finding and its importance? Moderate alcohol consumption for a short period of time impaired pulmonary vascular cellular renewal through an apoptosis resistance pattern that ultimately affected the right ventricular function and structure. These findings support the need for a deeper understanding of effects of moderate alcohol consumption on the overall cardiovascular and pulmonary systems. ABSTRACT: Over the past decades, observational studies have supported an association between moderate alcohol consumption and a lower risk of cardiovascular disease and mortality. However, recent and more robust meta-analyses have raised concerns around the robustness of the evidence for the cardioprotective effects of alcohol. Also, studies of the functional, structural and molecular changes promoted by alcohol have focused primarily on the left ventricle, ignoring the fact that the right ventricle could adapt differently. The aim of this study was to evaluate the bi-ventricular impact of daily moderate alcohol intake, during a 4-week period, in a rodent model. Male Wistar rats were allowed to drink water (Control) or a 5.2% ethanol mixture (ETOH) for 4 weeks. At the end of the protocol bi-ventricular haemodynamic recordings were performed and samples collected for further histological and molecular analysis. ETOH ingestion did not impact cardiac function. However, it caused right ventricle hypertrophy, paralleled by an activation of molecular pathways responsible for cell growth (ERK1/2, AKT), proteolysis (MURF-1) and oxidative stress (NOX4, SOD2). Furthermore, ETOH animals also presented remodelling of the pulmonary vasculature with an increase in pulmonary arteries' medial thickness, which was characterized by increased expression of apoptosis-related proteins expression (BCL-XL, BAX and caspases). Moderate alcohol consumption for a short period of time impaired the lungs and the right ventricle early, before any change could be detected on the left ventricle. Right ventricular changes might be secondary to alcohol-induced pulmonary vasculature remodelling.
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Ventrículos do Coração , Hipertensão Pulmonar , Consumo de Bebidas Alcoólicas , Animais , Pulmão/metabolismo , Masculino , Artéria Pulmonar , Ratos , Ratos Wistar , Função Ventricular Direita/fisiologiaRESUMO
Objective. (i) To compare daily physical activity (PA) levels evaluated by the International Physical Activity Questionnaire (IPAQ) and by triaxial accelerometry in heart failure with preserved ejection fraction (HFpEF) patients; (ii) to describe daily PA patterns based in objective measurements; and (iii) to observe the association between prognostic indicators and PA measurements. Design. This is a cross-sectional study with 24 stable HFpEF patients. PA was assessed through the IPAQ short version and triaxial accelerometer. Time spent in moderate-to-vigorous PA (MVPA) from IPAQ was computed as self-reported walking and MVPA. Prognostic indicators were: distance on the 6-minute-walking test (6MWT), oxygen consumption (VO2) during the test, quality of life (QoL), BNP plasma level, and E/e' ratio. Results. Compared to accelerometry, IPAQ underestimated sedentary time (253 ± 156 vs. 392 ± 104 min/day, p = .001) and overestimated MVPA (44 ± 56 vs. 19.3 ± 26 min/day, p < .001). Accelerometer-derived data showed that HFpEF patients spent 50% of their waking time in sedentary behaviours and 2.5% in MVPA. Of measured surrogate prognostic markers, functional capacity (6MWT, r = 0.652, p = .04; VO2, r = 0.512, p = .02) and QoL (r=-0.490, p = .04) were correlated with MVPA. Conclusions. The IPAQ underestimated sedentary time and over-estimated MVPA in HFpEF patients. Using accelerometer-derived data, HFpEF patients spent only a minority of their time involved in MVPA, which was the only PA pattern positively associated with prognostic indicators.
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Actigrafia/instrumentação , Exercício Físico , Monitores de Aptidão Física , Insuficiência Cardíaca/diagnóstico , Comportamento Sedentário , Volume Sistólico , Inquéritos e Questionários , Função Ventricular Esquerda , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Insuficiência Cardíaca/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Autorrelato , Fatores de TempoRESUMO
To analyze whether heart rate variability is reproducible after maximal exercise, 11 men (22.1±3.2 years) performed four incremental exercise tests followed by passive or active recovery. There was high reliability (intraclass coefficient correlation: 0.72-0.96) and fair-to-excellent agreement (coefficient of variation: 7.81-22.09%) in passive recovery, as well as moderate-to-high reliability (intraclass coefficient correlation: 0.50-0.87) and good agreement (coefficient of variation: 11.08-20.89%) in active recovery for LnRMSSD index. There was moderate-to-high reliability (intraclass coefficient correlation: 0.51-0.81) and good agreement (coefficient of variation: 10.41-18.87%) in most of the analyzed time points, in both recovery types for LnSDNN. In both types of recovery, the time domain heart rate variability 5-10 min indices (passive: intraclass coefficient correlation : 0.87-0.88; coefficient of variation: 7.67-13.44%; active: intraclass coefficient correlation 0.59-0.80; coefficient of variation: 14.62-16.26%) presented higher intraclass coefficient correlation and lower coefficient of variation than the spectral heart rate variability indices (passive: intraclass coefficient correlation: 0.71-0.87; coefficient of variation: 12.33-34.21%; active: intraclass coefficient correlation: 0.46-0.77; coefficient of variation: 24.41-105.12%). The LnRMSSD and LnSDNN indices analyzed in 30 s segments and the heart rate variability 5-10 min indices after maximal exercise in untrained healthy men showed satisfactory reproducibility, regardless of the type of recovery, with the time-domain indices showing higher reproducibility than the frequency-domain indices.
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Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Teste de Esforço , Coração/inervação , Humanos , Masculino , Sistema Nervoso Parassimpático/fisiologia , Reprodutibilidade dos Testes , Sistema Nervoso Simpático/fisiologia , Adulto JovemRESUMO
Limiting cancer-induced cardiac damage has become an increasingly important issue to improve survival rates and quality of life. Exercise training has been shown to reduce cardiovascular complications in several diseases; however, its therapeutic role against cardiovascular consequences of cancer is in its infancy. In order to add new insights on the potential therapeutic effect of exercise training on cancer-related cardiac dysfunction, we used an animal model of urothelial carcinoma submitted to 13 weeks of treadmill exercise after 20 weeks of exposure to the carcinogenic N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN). Data showed that 13 weeks of treadmill exercise reverted cancer-induced cardiomyocytes atrophy and fibrosis, improved cardiac oxidative capacity given by citrate synthase activity and MnSOD content, and increased the levels of the mitochondrial biogenesis markers PGC-1α and mtTFA. Moreover, exercise training reverted cancer-induced decrease of cardiac c-kit levels suggesting enhanced regenerative ability of heart. These cardiac adaptations to exercise were related to a lower incidence of malignant urothelial lesions and less signs of inflammation. Taken together, data from the present study support the beneficial effect of exercise training when started after cancer diagnosis, envisioning the improvement of the cardiovascular function.
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Remodelamento Atrial , Condicionamento Físico Animal , Neoplasias Urológicas/patologia , Animais , Modelos Animais de Doenças , Fibrose/prevenção & controle , Masculino , Atrofia Muscular/complicações , Atrofia Muscular/prevenção & controle , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Ratos , Ratos Wistar , Regeneração , Neoplasias Urológicas/metabolismo , Neoplasias Urológicas/fisiopatologiaRESUMO
Cardiac dysfunction secondary to cancer may exert a negative impact in patients' tolerance to therapeutics, quality of life, and survival. The aim of this study was to evaluate the potential therapeutic effect of exercise training on the heart in the setting of cancer, after diagnosis. Thus, the molecular pathways harbored in heart mitochondria from a murine model of chemically-induced urothelial carcinoma submitted to 8-weeks of high intensity treadmill exercise were characterized using mass spectrometry-based proteomics. Data highlight the protective effects of high intensity exercise training in preventing left ventricle diastolic dysfunction, fibrosis, and structural derangement observed in tumor-bearing mice. At the mitochondrial level, exercise training counteracted the lower ability to produce ATP observed in the heart of animals with urothelial carcinoma and induced the up-regulation of fatty acid oxidation and down-regulation of the biological process "cardiac morphogenesis". Taken together, our data support the prescription of exercise training after cancer diagnosis for the management of disease-related cardiac dysfunction.
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Carcinoma/complicações , Mitocôndrias Cardíacas/metabolismo , Condicionamento Físico Animal/métodos , Proteoma/metabolismo , Neoplasias da Bexiga Urinária/complicações , Disfunção Ventricular Esquerda/prevenção & controle , Animais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Miócitos Cardíacos/metabolismo , Proteoma/genética , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/metabolismoRESUMO
Pulmonary arterial hypertension (PAH) is a progressive disease with a poor prognosis. Pulmonary artery smooth muscle cells (PASMCs) play a crucial role in PAH pathophysiology, displaying a hyperproliferative, and apoptotic-resistant phenotype. In the present study, we evaluated the potential therapeutic role of terameprocol (TMP), an inhibitor of cellular proliferation and promoter of apoptosis, in a well-established pre-clinical model of PAH induced by monocrotaline (MCT) and studied the biological pathways modulated by TMP in PASMCs. Wistar rats injected with MCT or saline (SHAM group) were treated with TMP or vehicle. On day 21 after injection, we assessed bi-ventricular hemodynamics and cardiac and pulmonary morphometry. The effects of TMP on PASMCs were studied in a primary culture isolated from SHAM and MCT-treated rats, using an iTRAQ-based proteomic approach to investigate the molecular pathways modulated by this drug. In vivo, TMP significantly reduced pulmonary and cardiac remodeling and improved cardiac function in PAH. In vitro, TMP inhibited proliferation and induced apoptosis of PASMCs. A total of 65 proteins were differentially expressed in PASMCs from MCT rats treated with TMP, some of which involved in the modulation of transforming growth factor beta pathway and DNA transcription. Anti-proliferative effect of TMP seems to be explained, at least in part, by the down-regulation of the transcription factor HMGB1. Our findings support the beneficial role of TMP in PAH and suggest that it may be an effective therapeutic option to be considered in the clinical management of PAH.
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Anti-Hipertensivos/farmacologia , Proliferação de Células/efeitos dos fármacos , Proteína HMGB1/metabolismo , Hipertensão/tratamento farmacológico , Masoprocol/análogos & derivados , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Remodelação Vascular/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Regulação para Baixo , Hemodinâmica/efeitos dos fármacos , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Hipertensão/patologia , Masculino , Masoprocol/farmacologia , Monocrotalina , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Mapas de Interação de Proteínas , Proteômica/métodos , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Ratos Wistar , Recuperação de Função Fisiológica , Fatores de Tempo , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Direita/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacosRESUMO
Cachexia, or muscle wasting, is a complex metabolic syndrome associated with an underlying illness and characterized by loss of muscle mass. It is a rather prevalent condition, with impacts on patient survival, response to treatment, and quality of life. Treatment options are sparse because of cachexia's multifactorial pathogenesis. Recently, attention has focused on microRNAs (miRNAs) as potential therapeutic targets of several diseases. miRNAs are small, 18- to 25-base-long constructs that regulate gene expression on a post-transcriptional level, selectively activating or repressing elements of specific signaling pathways. In this review, we investigated whether miRNAs play any role in cachexia's biochemical pathways and if miRNA targeting has any significant impact on preclinical models of cachexia.
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Caquexia/metabolismo , MicroRNAs , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Animais , HumanosRESUMO
Exercise training (ExT) is widely used for the prevention and treatment of several chronic cardiovascular diseases. However, only recently it started to be recognized as safe and beneficial in pulmonary arterial hypertension. Despite the consistency of its favorable effects on exercise tolerance and quality of life, the mechanisms underlying these meaningful clinical improvements remain unclear. Current studies emphasize the exercise-induced changes on skeletal muscle but the impact of ExT at the level of the pulmonary circulation and right ventricle should not be overlooked. In this chapter, we summarize the main findings from pre-clinical studies analyzing the impact of exercise in pulmonary hypertension and right heart failure.
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Modelos Animais de Doenças , Exercício Físico/fisiologia , Insuficiência Cardíaca/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Condicionamento Físico Animal/fisiologia , Animais , Tolerância ao Exercício/fisiologia , Humanos , Músculo Esquelético/fisiopatologiaRESUMO
BACKGROUND: The non-alcoholic fatty liver disease is the hepatic counterpart of the metabolic syndrome. ZSF1 rats are a metabolic syndrome animal model in which liver changes have not been described yet. AIM: The characterization of liver histological and innate immunity changes in ZSF1 rats. METHODS: Five groups of rats were included (n = 7 each group): healthy Wistar-Kyoto control rats (Ctrl), hypertensive ZSF1 lean (Ln), ZSF1 obese rats with a normal diet (Ob), ZSF1 obese rates with a high-fat diet (Ob-HFD), and ZSF1 obese rats with low-intensity exercise training (Ob-Ex). The animals were sacrificed at 20 weeks of age, their livers were collected for: a) measurements of the area of steatosis, fibrosis and inflammation (histomorphological analysis); and b) innate immunity (toll-like receptor [TLR] 2, TLR4, peroxisome proliferator-activated receptor γ [PPARγ], toll interacting protein [TOLLIP]) and inflammatory marker (tumor necrosis factor-alpha [TNFα], interleukin 1 [IL-1]) expression analysis by real-time PCR. RESULTS: Ob, Ob-HFD and Ob-Ex were significantly heavier than Ln and Ctrl animals. Ob, Ob-HFD and Ob-Ex animals had impaired glucose tolerance and insulin resistance. ZSF1 Ob, Ob-HFD and Ob-Ex presented a higher degree of steatosis (3,5x; p < 0.05) than Ctrl or ZSF1 Ln rats. Steatohepatitis and fibrosis were not observed in any of the groups. No differences in expression were observed between Ctrl, Ln and Ob animals (except for the significantly higher expression of TOLLIP observed in the Ob vs Ln comparison). Ob-HFD and Ob-Ex rats showed increased expression of PPARγ and TOLLIP as compared to other groups. However, both groups also showed increased expression of TLR2 and TLR4. Nevertheless, this did not translate into a differential expression of TNFα or IL-1 in any of the groups. CONCLUSION: The ZSF1 model is associated with liver steatosis but not with steatohepatitis or a significantly increased expression of innate immunity or inflammation markers.
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Fígado/patologia , Síndrome Metabólica/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , Expressão Gênica/genética , Masculino , Síndrome Metabólica/genética , Obesidade , Ratos , Ratos Endogâmicos WKYRESUMO
INTRODUCTION: Frailty can be defined as a biological syndrome of reduced reserve and resistance to stressful events. Evidence suggests that this syndrome is linked to adverse outcomes in various surgical populations. Several instruments have been developed to measure frailty, however there is no consensus about which one is the most useful in the surgical population. Therefore, this study aims to evaluate the utility of different frailty scales in the prediction of postoperative complications in older surgical population. METHODS: This review and meta-analysis assembles prospective cohort studies reporting frailty and postoperative outcomes. Searches were performed in PubMed/Medline, Scielo, Cochrane Library and ScienceDirect databases. Statistical analyses was performed using Review Manager software and the pooled Odds Rattios was calculated. RESULTS: A total of 15 articles were included in the present review. Frailty was significantly associated with postoperative complications (OR=2.53, 95% CI: 2.07-3.10; p<0.00001), mortality until 30 days (OR=3.49, 95% CI: 2.40-5.09, p<0.00001) and higher 1-year mortality (OR= 2.90, 95% CI: 1.99-4.24, p<0.00001), and with hospital length of stay >5days or >14days (OR=2.78, 95% CI: 1.45-5.30, p=0.002 and OR=2.40 (95% CI: 1.08-5.36, p= 0.03, respectively). In addition, our meta-analysis showed that frailty is a significant predictor of renal failure (OR=5.03, 95% CI: 1.74-14.54, p=0.003), neurological complications (OR= 3.41, 95% CI: 1.08-10.73, p=0.04), respiratory complications (OR=9.21 (95% CI: 2.35- 36.02, p=0.001), wound infection (OR=2.85 (95% CI: 1.65-4.94, p=0.0002) and sepsis (OR=3.84 (95% CI: 1.37-10.71, p=0.01). CONCLUSION: Overall, frailty significantly increases the risk for developing adverse outcomes after surgery, so early detection of frailty may be a window of opportunity for intervention and a key factor for improving clinical outcomes. Moreover, future studies are required for the standardization of the frailty scales used.
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Fragilidade , Complicações Pós-Operatórias , Previsões , Humanos , Período Pós-Operatório , Prognóstico , Estudos ProspectivosRESUMO
The present study aimed to test whether a chronic intermittent workload could induce an adaptive cardiac phenotype Chronic intermittent workload induced features of adaptive hypertrophy This was paralleled by protection against acute pressure overload insult The heart may adapt favourably to balanced demands, regardless of the nature of the stimuli. The present study aimed to test whether submitting the healthy heart to intermittent and tolerable amounts of workload, independently of its nature, could result in an adaptive cardiac phenotype. Male Wistar rats were subjected to treadmill running (Ex) (n = 20), intermittent cardiac overload with dobutamine (ITO) (2 mg kg(-1) , s.c.; n = 20) or placebo administration (Cont) (n = 20) for 5 days week(-1) for 8 weeks. Animals were then killed for histological and biochemical analysis or subjected to left ventricular haemodynamic evaluation under baseline conditions, in response to isovolumetric contractions and to sustained LV acute pressure overload (35% increase in peak systolic pressure maintained for 2 h). Baseline cardiac function was enhanced only in Ex, whereas the response to isovolumetric heartbeats was improved in both ITO and Ex. By contrast to the Cont group, in which rats developed diastolic dysfunction with sustained acute pressure overload, ITO and Ex showed increased tolerance to this stress test. Both ITO and Ex developed cardiomyocyte hypertrophy without fibrosis, no overexpression of osteopontin-1 or ß-myosin heavy chain, and increased expression of sarcoplasmic reticulum Ca(2+) protein. Regarding hypertrophic pathways, ITO and Ex showed activation of the protein kinase B/mammalian target of rapamycin pathway but not calcineurin. Mitochondrial complex IV and V activities were also increased in ITO and Ex. Chronic submission to controlled intermittent cardiac overload, independently of its nature, results in an adaptive cardiac phenotype. Features of the cardiac overload, such as the duration and magnitude of the stimuli, may play a role in the development of an adaptive or maladaptive phenotype.
Assuntos
Adaptação Fisiológica , Cardiomegalia , Animais , Pressão Sanguínea , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Cardiotônicos/farmacologia , Dobutamina/farmacologia , Coração/fisiologia , Masculino , Mitocôndrias Cardíacas/fisiologia , Miocárdio/patologia , Tamanho do Órgão , Fenótipo , Condicionamento Físico Animal/fisiologia , Ratos Wistar , Corrida/fisiologiaRESUMO
Alterations in muscle mitochondrial bioenergetics during cancer cachexia were previously suggested; however, the underlying mechanisms are not known. So, the goal of this study was to evaluate mitochondrial phospholipid remodeling in cancer-related muscle wasting and its repercussions to respiratory chain activity and fiber susceptibility to apoptosis. An animal model of urothelial carcinoma induced by exposition to N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) and characterized by significant body weight loss due to skeletal muscle mass decrease was used. Morphological evidences of muscle atrophy were associated to decreased respiratory chain activity and increased expression of mitochondrial UCP3, which altogether highlight the lower ability of wasted muscle to produce ATP. Lipidomic analysis of isolated mitochondria revealed a significant decrease of phosphatidic acid, phosphatidylglycerol and cardiolipin in BBN mitochondria, counteracted by increased phosphatidylcholine levels. Besides the impact on membrane fluidity, this phospholipid remodeling seems to justify, at least in part, the lower oxidative phosphorylation activity observed in mitochondria from wasted muscle and their increased susceptibility to apoptosis. Curiously, no evidences of lipid peroxidation were observed but proteins from BBN mitochondria, particularly the metabolic ones, seem more prone to carbonylation with the consequent implications in mitochondria functionality. Overall, data suggest that bladder cancer negatively impacts skeletal muscle activity specifically by affecting mitochondrial phospholipid dynamics and its interaction with proteins, ultimately leading to the dysfunction of this organelle. The regulation of phospholipid biosynthetic pathways might be seen as potential therapeutic targets for the management of cancer-related muscle wasting.
Assuntos
Metabolismo Energético/genética , Atrofia Muscular/metabolismo , Estresse Oxidativo/genética , Neoplasias da Bexiga Urinária/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Apoptose/genética , Butilidroxibutilnitrosamina/toxicidade , Humanos , Canais Iônicos/metabolismo , Peroxidação de Lipídeos/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/etiologia , Atrofia Muscular/patologia , Proteína Desacopladora 3 , Neoplasias da Bexiga Urinária/induzido quimicamente , Neoplasias da Bexiga Urinária/complicações , Neoplasias da Bexiga Urinária/patologiaRESUMO
Exercise training is a well-known non-pharmacological strategy for the prevention and treatment of cardiovascular diseases. Despite the established phenotypic knowledge, the molecular signature of exercise-induced cardiac remodeling remains poorly characterized. The great majority of studies dedicated to this topic use conventional reductionist methods, which only allow analyzing individual protein candidates. Nowadays, several methodologies based on mass spectrometry are available and have been successfully applied for the characterization of heart proteome, representing an attractive approach for the wide characterization of the complex molecular networks that underlie exercise-induced cardiac remodeling. Still, few studies have used these methodologies to understand the impact of exercise training on the remodeling of cardiac proteome. The present study analyzes the few available data obtained from mass spectrometry (MS)-based proteomic studies assessing the impact of distinct types of exercise training on the protein profile of heart (left ventricle and isolated mitochondria) and the potential cross-tolerance between exercise training and diseases as myocardial infarction and obesity. Network analysis was performed with bioinformatics to integrate data from distinct research papers, based on distinct exercise training protocols, animal models and methodological approaches applied in the characterization of heart proteome. The analysis revealed that exercise training confers a unique proteome signature characterized by the up-regulation of lipid and organic metabolic processes, vasculogenesis and tissue regeneration. Data retrieved from this analysis also suggested that cardiac mitochondrial proteome is highly dynamic in response to exercise training due, in part, to the action of specific kinases as PKA and PKG. Regarding to the type of exercise, treadmill training seems to have a greater effect on the modulation of cardiac proteome than swimming. Data from the present review will certainly open new perspectives on cardiac proteomics and will help to envisage future studies targeting the identification of the regulatory mechanisms underlying cardiac adaptive and maladaptive remodeling.