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1.
ESC Heart Fail ; 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31877587

RESUMO

AIMS: The definition of sarcopenia based on appendicular lean mass/height (2) (ALM/height (2) ) is often used, although it can underestimate the prevalence of sarcopenia in overweight/obese patients with heart failure. Therefore, new methods have been proposed to overcome this limitation. We aimed to evaluate the prevalence of sarcopenia by three methods and compare body composition in this population. METHODS AND RESULTS: We enrolled 168 male patients with heart failure (left ventricular ejection fraction <40%). Sixty-six patients (39.3%) were identified with sarcopenia by at least one method. The lower 20th percentile defined as the cut-off point for sarcopenia was 7.03 kg/m2 , -2.32 and 0.76 for Baumgartner's (20.8%), Newman's (21.4%), and Studenski's methods (21.4%), respectively. Patients with body mass index (BMI) <25 kg/m2 were more likely to be identified by Baumgartner's than Studenski's method (P < 0.001). However, in patients with BMI ≥ 25 kg/m2 , Studenski's and Newman's methods were more likely to detect sarcopenia than Baumgartner's method (both P < 0.005). Patients were further divided into three subgroups: (i) patients classified in all indexes (n = 8), (ii) patients classified in Baumgartner's (sarcopenic; n = 27), and (iii) patients classified in both Newman's and Studenski's methods (sarcopenic obesity; n = 31). Comparing body composition among groups, all sarcopenic groups presented lower total lean mass compared with non-sarcopenic patients, whereas sarcopenic obese patients had higher total lean mass than lean sarcopenic patients. CONCLUSIONS: Our results demonstrate that the prevalence of sarcopenia in overweight/obese patients is similar to lean sarcopenic patients when other methods are considered. In patients with higher BMI, Studenski's method seems to be more feasible to detect sarcopenia.

2.
Artigo em Inglês | MEDLINE | ID: mdl-31743617

RESUMO

BACKGROUND: The exercise intolerance in chronic heart failure with reduced ejection fraction (HFrEF) is mostly attributed to alterations in skeletal muscle. However, the mechanisms underlying the skeletal myopathy in patients with HFrEF are not completely understood. We hypothesized that (i) aerobic exercise training (AET) and inspiratory muscle training (IMT) would change skeletal muscle microRNA-1 expression and downstream-associated pathways in patients with HFrEF and (ii) AET and IMT would increase leg blood flow (LBF), functional capacity, and quality of life in these patients. METHODS: Patients age 35 to 70 years, left ventricular ejection fraction (LVEF) ≤40%, New York Heart Association functional classes II-III, were randomized into control, IMT, and AET groups. Skeletal muscle changes were examined by vastus lateralis biopsy. LBF was measured by venous occlusion plethysmography, functional capacity by cardiopulmonary exercise test, and quality of life by Minnesota Living with Heart Failure Questionnaire. All patients were evaluated at baseline and after 4 months. RESULTS: Thirty-three patients finished the study protocol: control (n = 10; LVEF = 25 ± 1%; six males), IMT (n = 11; LVEF = 31 ± 2%; three males), and AET (n = 12; LVEF = 26 ± 2%; seven males). AET, but not IMT, increased the expression of microRNA-1 (P = 0.02; percent changes = 53 ± 17%), decreased the expression of PTEN (P = 0.003; percent changes = -15 ± 0.03%), and tended to increase the p-AKTser473 /AKT ratio (P = 0.06). In addition, AET decreased HDAC4 expression (P = 0.03; percent changes = -40 ± 19%) and upregulated follistatin (P = 0.01; percent changes = 174 ± 58%), MEF2C (P = 0.05; percent changes = 34 ± 15%), and MyoD expression (P = 0.05; percent changes = 47 ± 18%). AET also increased muscle cross-sectional area (P = 0.01). AET and IMT increased LBF, functional capacity, and quality of life. Further analyses showed a significant correlation between percent changes in microRNA-1 and percent changes in follistatin mRNA (P = 0.001, rho = 0.58) and between percent changes in follistatin mRNA and percent changes in peak VO2 (P = 0.004, rho = 0.51). CONCLUSIONS: AET upregulates microRNA-1 levels and decreases the protein expression of PTEN, which reduces the inhibitory action on the PI3K-AKT pathway that regulates the skeletal muscle tropism. The increased levels of microRNA-1 also decreased HDAC4 and increased MEF2c, MyoD, and follistatin expression, improving skeletal muscle regeneration. These changes associated with the increase in muscle cross-sectional area and LBF contribute to the attenuation in skeletal myopathy, and the improvement in functional capacity and quality of life in patients with HFrEF. IMT caused no changes in microRNA-1 and in the downstream-associated pathway. The increased functional capacity provoked by IMT seems to be associated with amelioration in the respiratory function instead of changes in skeletal muscle. ClinicalTrials.gov (Identifier: NCT01747395).

3.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 29(4 (Supl)): 393-399, out.-dez. 2019. tab
Artigo em Português | LILACS | ID: biblio-1047325

RESUMO

A testosterona, hormônio masculino com efeitos androgênicos e anabólicos, também exerce efeito sobre o leito vascular. Este hormônio promove vasodilatação através da liberação de óxido nítrico e modulação dos canais de cálcio que impacta a função endotelial. Em pacientes com doença arterial coronariana (DAC) e insuficiência cardíaca (IC), reduções nas concentrações de testosterona total (<300 ng/dL) estão relacionadas com maior mortalidade e severidade dessas doenças. Em pacientes com DAC, a reposição de testosterona (RT) tem relação com melhora do tônus vascular coronário e melhora do limiar de isquemia. Em pacientes com IC, os efeitos parecem estar mais relacionados à melhora da capacidade funcional, aumento na distância percorrida em testes funcionais, maior VO2máx, menor razão VE/VCO2, e melhora adicional da sensibilidade barorreflexa. No entanto, embora os efeitos da testosterona sobre o aumento de massa muscular e força muscular estejam bem estabelecidos na literatura, os efeitos dessa substância no sistema cardiovascular precisam ser elucidados. O aumento das concentrações de antígeno prostático específico da próstata tem sido constantemente discutido quando a RT é proposta no tratamento de pacientes com doenças cardiovasculares. Por se tratar de um hormônio com grande potencial anabólico, os efeitos do uso de quantidades suprafisiológicas de testosterona e seus análogos sobre as alterações cardiovasculares em jovens atletas têm sido estudados. Portanto, o objetivo dessa revisão é abordar os efeitos benéficos da RT em homens com hipogonadismo com DAC e IC, e mostrar os riscos relacionados com a prática indiscriminada do uso de anabolizantes em jovens sem deficiência de testosterona


Testosterone, the male hormone with androgenic and anabolic effects, also has an effect on the vascular bed. This hormone promotes vasodilation by releasing nitric oxide and calcium channel modulation that impacts endothelial function. In patients with coronary artery disease (CAD) and heart failure (HF), reductions in total testosterone concentrations (<300 ng/dL) are related to higher mortality and severity of these diseases. In patients with CAD, testosterone replacement (TR) is related to improved coronary vascular tone and improved ischemia threshold. In HF patients, the effects seem be more related to improved functional capacity, increased distance covered in functional tests, higher VO2max, lower LV/VCO2 ratio, and further improvement of baroreflex sensitivity. However, although the effects of testosterone on muscle mass gain and muscle strength are well established in the literature, the effects of testosterone on the cardiovascular system need to be elucidated. Increased prostate-specific prostate antigen concentrations have been constantly discussed when TR is proposed in the treatment of patients with cardiovascular disease. Because it is a hormone with great anabolic potential, the effects of supraphysiological amounts of testosterone and its analogues on cardiovascular disorders in young athletes have been studied. Therefore, the objective of this review is to address the beneficial effects of TR in men with hypogonadism with CAD and HF, and to show the risks related to anabolic steroids abuse in young people without testosterone deficiency


Assuntos
Testosterona , Doenças Cardiovasculares/terapia , Doença da Artéria Coronariana , Sistema Cardiovascular , Exercício , Vasos Coronários , Insuficiência Cardíaca Diastólica , Hormônios , Hipogonadismo
4.
Arq. bras. cardiol ; 112(6): 739-746, Jun. 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1011203

RESUMO

Abstract Background: Resting sympathetic hyperactivity and impaired parasympathetic reactivation after exercise have been described in patients with heart failure (HF). However, the association of these autonomic changes in patients with HF and sarcopenia is unknown. Objective: The aim of this study was to evaluate the impact of autonomic modulation on sarcopenia in male patients with HF. Methods: We enrolled 116 male patients with HF and left ventricular ejection fraction < 40%. All patients underwent a maximal cardiopulmonary exercise testing. Maximal heart rate was recorded and delta heart rate recovery (∆HRR) was assessed at 1st and 2nd minutes after exercise. Muscle sympathetic nerve activity (MSNA) was recorded by microneurography. Dual-energy X-ray absorptiometry was used to measure body composition and sarcopenia was defined by the sum of appendicular lean muscle mass (ALM) divided by height in meters squared and handgrip strength. Results: Sarcopenia was identified in 33 patients (28%). Patients with sarcopenia had higher MSNA than those without (47 [41-52] vs. 40 [34-48] bursts/min, p = 0.028). Sarcopenic patients showed lower ∆HRR at 1st (15 [10-21] vs. 22 [16-30] beats/min, p < 0.001) and 2nd min (25 [19-39] vs. 35 [24-48] beats/min, p = 0.017) than non-sarcopenic. There was a positive correlation between ALM and ∆HRR at 1st (r = 0.26, p = 0.008) and 2nd min (r = 0.25, p = 0.012). We observed a negative correlation between ALM and MSNA (r = -0.29, p = 0.003). Conclusion: Sympatho-vagal imbalance seems to be associated with sarcopenia in male patients with HF. These results highlight the importance of a therapeutic approach in patients with muscle wasting and increased peripheral sympathetic outflow.


Resumo Fundamento: Hiperatividade simpática de repouso e uma reativação parassimpática diminuída pós-exercício têm sido descritas em pacientes com insuficiência cardíaca (IC). No entanto, a associação dessas alterações autonômicas em pacientes com IC sarcopênicos ainda não são conhecidas. Objetivo: O objetivo deste estudo foi avaliar o impacto da modulação autonômica sobre sarcopenia em pacientes com IC do sexo masculino. Métodos: Foram estudados 116 pacientes com IC e fração de ejeção ventricular esquerda inferior a 40%. Todos os pacientes foram submetidos ao teste de exercício cardiopulmonar máximo. A frequência cardíaca máxima foi registrada, e o delta de recuperação da frequência cardíaca (∆RFC) foi avaliado no primeiro e no segundo minuto após o exercício. A atividade nervosa simpática muscular (ANSM) foi registrada por microneurografia. A Absorciometria Radiológica de Dupla Energia foi usada para medir composição cpororal, e a sarcopenia definida como a soma da massa muscular apendicular (MMA) dividida pela altura em metros ao quadrado e força da mão. Resultados: A sarcopenia foi identificada em 33 pacientes (28%). Os pacientes com sarcopenia apresentaram maior ANSM que aqueles sem sarcopenia - 47 (41-52) vs. 40 (34-48) impulsos (bursts)/min, p = 0,028). Pacientes sarcopênicos apresentaram ∆RFC mais baixo no primeiro [15 (10-21) vs. 22 (16-30) batimentos/min, p < 0,001) e no segundo [25 (19-39) vs. 35 (24-48) batimentos/min, p = 0,017) minuto que pacientes não sarcopênicos. Observou-se uma correlação positiva entre a MMA e a ANSM (r = -0,29; p = 0,003). Conclusão: Um desequilíbrio simpático-vagal parece estar associado com sarcopenia em pacientes com IC do sexo masculino. Esses resultados destacam a importância de uma abordagem terapêutica em pacientes com perda muscular e fluxo simpático periférico aumentado.

5.
Lipids ; 54(6-7): 381-388, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31141200

RESUMO

Exercise training not only improves the plasma lipid profile but also reduces risk of developing coronary heart disease. We investigate whether plasma lipids and high density lipoprotein (HDL) metabolism are affected by aerobic training and whether the high-density lipoprotein cholesterol (HDL-C) levels at baseline influence exercise-induced changes in HDL. Seventy-one male sedentary volunteers were evaluated and allocated in two subgroups, according to the HLD-C levels (< or >40 mg/dL). Participants underwent an 18-week aerobic training period. Blood was sampled before and after training for biochemical analysis. Plasma lipids, apolipoproteins, HDL diameter, and VO2 peak were determined. Lipid transfers to HDL were determined in vitro by incubating plasma samples with a donor lipid artificial nanoemulsion. After the 18-week period of aerobic training, the VO2 peak increased, while the mean body mass index (BMI) decreased. HDL-C concentration was higher after the training period, but low-density lipoprotein cholesterol (LDL-C) and non-HDL-C did not change. The transfer of esterified cholesterol and phospholipids was greater after exercise training, but the triacylglycerol and unesterified cholesterol transfers were unchanged. The HDL particle diameter increased after aerobic training in all participants. When the participants were separated in low-HDL and normal-HDL groups, the postaerobic exercise increment in HDL-C was higher in the low-HDL group, while the transfer of esterified cholesterol was lower. In conclusion, aerobic exercise training increases the lipid transfers to HDL, as measured by an in vitro method, which possibly contributes to the classical elevation of the HDL-C associated with training.

6.
Am J Physiol Heart Circ Physiol ; 317(7): H1-H12, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31002284

RESUMO

The purpose of the present study was to test the hypothesis that doxorubicin (DX) and cyclophosphamide (CY) adjuvant chemotherapy (CHT) acutely impairs neurovascular and hemodynamic responses in women with breast cancer. Sixteen women (age: 47.0 ± 2.0 yr; body mass index: 24.2 ± 1.5 kg/m) with stage II-III breast cancer and indication for adjuvant CHT underwent two experimental sessions, saline (SL) and CHT. In the CHT session, DX (60 mg/m2) and CY (600 mg/m2) were administered over 45 min. In the SL session, a matching SL volume was infused in 45 min. Muscle sympathetic nerve activity (MSNA) from peroneal nerve (microneurography), calf blood flow (CBF; plethysmography) and calf vascular conductance (CVC), heart rate (HR; electrocardiography), and beat-to-beat blood pressure (BP; finger plethysmography) were measured at rest before, during, and after each session. Venous blood samples (5 ml) were collected before and after both sessions for assessment of circulating endothelial microparticles (EMPs; flow cytometry), a surrogate marker for endothelial damage. MSNA and BP responses were increased (P < 0.001), whereas CBF and CVC responses were decreased (P < 0.001), during and after CHT session when compared with SL session. Interestingly, the vascular alterations were also observed at the molecular level through an increased EMP response to CHT (P = 0.03, CHT vs. SL session). No difference in HR response was observed (P > 0.05). Adjuvant CHT with DX and CY in patients treated for breast cancer increases sympathetic nerve activity and circulating EMP levels and, in addition, reduces muscle vascular conductance and elevates systemic BP. These responses may be early signs of CHT-induced cardiovascular alterations and may represent potential targets for preventive interventions. NEW & NOTEWORTHY It is known that chemotherapy regimens increase the risk of cardiovascular events in patients treated for cancer. Here, we identified that a single cycle of adjuvant chemotherapy with doxorubicin and cyclophosphamide in women treated for breast cancer dramatically increases sympathetic nerve activity and circulating endothelial microparticle levels, reduces the muscle vascular conductance, and elevates systemic blood pressure.

7.
Arq Bras Cardiol ; 112(6): 739-746, 2019 Jun.
Artigo em Inglês, Português | MEDLINE | ID: mdl-30970141

RESUMO

BACKGROUND: Resting sympathetic hyperactivity and impaired parasympathetic reactivation after exercise have been described in patients with heart failure (HF). However, the association of these autonomic changes in patients with HF and sarcopenia is unknown. OBJECTIVE: The aim of this study was to evaluate the impact of autonomic modulation on sarcopenia in male patients with HF. METHODS: We enrolled 116 male patients with HF and left ventricular ejection fraction < 40%. All patients underwent a maximal cardiopulmonary exercise testing. Maximal heart rate was recorded and delta heart rate recovery (∆HRR) was assessed at 1st and 2nd minutes after exercise. Muscle sympathetic nerve activity (MSNA) was recorded by microneurography. Dual-energy X-ray absorptiometry was used to measure body composition and sarcopenia was defined by the sum of appendicular lean muscle mass (ALM) divided by height in meters squared and handgrip strength. RESULTS: Sarcopenia was identified in 33 patients (28%). Patients with sarcopenia had higher MSNA than those without (47 [41-52] vs. 40 [34-48] bursts/min, p = 0.028). Sarcopenic patients showed lower ∆HRR at 1st (15 [10-21] vs. 22 [16-30] beats/min, p < 0.001) and 2nd min (25 [19-39] vs. 35 [24-48] beats/min, p = 0.017) than non-sarcopenic. There was a positive correlation between ALM and ∆HRR at 1st (r = 0.26, p = 0.008) and 2nd min (r = 0.25, p = 0.012). We observed a negative correlation between ALM and MSNA (r = -0.29, p = 0.003). CONCLUSION: Sympatho-vagal imbalance seems to be associated with sarcopenia in male patients with HF. These results highlight the importance of a therapeutic approach in patients with muscle wasting and increased peripheral sympathetic outflow.

8.
Atherosclerosis ; 283: 100-105, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30826541

RESUMO

BACKGROUND AND AIMS: Anabolic androgenic steroids (AAS) have been associated with coronary artery disease (CAD). AAS abuse leads to a remarkable decrease in high-density lipoprotein (HDL) plasma concentration, which could be a key factor in the atherosclerotic process. Moreover, not only the concentration of HDL, but also its functionality, plays a pivotal role in CAD. We tested the functionality of HDL by cholesterol efflux and antioxidant capacity. We also evaluated the prevalence of CAD in AAS users. METHODS: Twenty strength-trained AAS users (AASU) age 29 ±â€¯5 yr, 20 age-matched strength-trained AAS nonusers (AASNU), and 10 sedentary controls (SC) were enrolled in this cross-sectional study. Functionality of HDL was evaluated by 14C-cholesterol efflux and the ability of HDL in inhibiting LDL oxidation. Coronary artery was evaluated with coronary computed tomography angiography. RESULTS: Cholesterol efflux was lower in AASU compared with AASNU and SC (20 vs. 23 vs. 24%, respectively, p < 0.001). However, the lag time for LDL oxidation was higher in AASU compared with AASNU and SC (41 vs 13 vs 11 min, respectively, p < 0.001). We found at least 2 coronary arteries with plaques in 25% of AASU. None of the AASNU and SC had plaques. The time of AAS use was negatively associated with cholesterol efflux. CONCLUSIONS: This study indicates that AAS abuse impairs the cholesterol efflux mediated by HDL. Long-term AAS use seems to be correlated with lower cholesterol efflux and early subclinical CAD in this population.

9.
Scand J Med Sci Sports ; 29(3): 422-429, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30387184

RESUMO

Disturbed shear rate (SR), characterized by increased retrograde and oscillatory SR in the brachial artery, is associated with inflammation, atherosclerosis, endothelial dysfunction, and sympathetic hyperactivity. Young subjects do not have disturbed SR; however, elderly subjects do, which seems to be associated with sympathetic hyperactivity. Anabolic androgenic steroids (AAS) abuse in young is associated with increased muscle sympathetic nerve activity (MSNA). We hypothesized that AAS users might have disturbed SR. We tested the association between retrograde and oscillatory SR with MSNA. In addition, we measured the high-sensitivity C-reactive protein (hs-CRP). We evaluated 10 male AAS users, age 27 ± 4 years, and 10 age-matched AAS nonusers, age 29 ± 5 years. At rest, retrograde and oscillatory SR were evaluated by Doppler ultrasound, MSNA was measured with microneurography, and hs-CRP was measured in blood sample. Flow-mediated dilation (FMD) was also assessed. AAS users had higher retrograde SR (24.42 ± 17.25 vs 9.15 ± 6.62 s- 1 , P = 0.01), oscillatory SR (0.22 ± 0.13 vs 0.09 ± 0.07 au P = 0.01), and MSNA (42 ± 9 vs 32 ± 4 bursts/100 heart beats, P = 0.018) than nonusers. MSNA (bursts/100 heart beats) was correlated with retrograde SR (r = 0.50, P = 0.050) and oscillatory SR (r = 0.51, P = 0.042). AAS users had higher hs-CRP [1.17 (0.44-3.63) vs 0.29 (0.17-0.70) mg/L, P = 0.015] and decreased FMD (6.42 ± 2.07 vs 8.28% ± 1.53%, P = 0.035) than nonusers. In conclusion, AAS abuse is associated with retrograde and oscillatory SR which were associated with augmented sympathetic outflow. In addition, AAS seems to lead to inflammation characterized by increased hs-CRP. These alterations may have the potential of increasing the early risk of atherosclerotic disease in young AAS users.


Assuntos
Anabolizantes/efeitos adversos , Artéria Braquial/fisiopatologia , Esteroides/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Adulto , Aterosclerose , Proteína C-Reativa/análise , Estudos de Casos e Controles , Estudos Transversais , Frequência Cardíaca , Humanos , Masculino , Oscilometria , Fatores de Risco , Sistema Nervoso Simpático , Adulto Jovem
10.
Med Sci Sports Exerc ; 51(3): 426-435, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30312214

RESUMO

INTRODUCTION/PURPOSE: We demonstrated that patients with obstructive sleep apnea (OSA) have reduced muscle metaboreflex control of muscle sympathetic nerve activity (MSNA). In addition, exercise training increased muscle metaboreflex control in heart failure patients. OBJECTIVE: We tested the hypothesis that exercise training would increase muscle metaboreflex control of MSNA in patients with OSA. METHODS: Forty-one patients with OSA were randomized into the following two groups: 1) nontrained (OSANT, n = 21) and 2) trained (OSAT, n = 20). Muscle sympathetic nerve activity was assessed by microneurography technique, muscle blood flow (FBF) by venous occlusion plethysmography, heart rate by electrocardiography, and blood pressure with an automated oscillometric device. All physiological variables were simultaneously assessed at rest, during isometric handgrip exercise at 30% of the maximal voluntary contraction, and during posthandgrip muscle ischemia (PHMI). Muscle metaboreflex sensitivity was calculated as the difference in MSNA between PHMI and the rest period. Patients in the OSAT group underwent 72 sessions of moderate exercise training, whereas patients in the OSANT group were clinical follow-up for 6 months. RESULTS: The OSANT and OSAT groups were similar in anthropometric, neurovascular, hemodynamic and sleep parameters. Exercise training reduced the baseline MSNA (34 ± 2 bursts per minute vs 25 ± 2 bursts per minute; P < 0.05) and increased the baseline FBF (2.1 ± 0.2 mL·min per 100 g vs 2.4 ± 0.2 mL·min per 100 g; P < 0.05). Exercise training significantly reduced MSNA levels and increased FBF responses during isometric exercise. Exercise training significantly increased MSNA responses during PHMI (Δ6.5 ± 1 vs -1.7 ± 1 bursts per minute, P < 0.01). No significant changes in FBF or hemodynamic parameters in OSANT patients were found. CONCLUSIONS: Exercise training increases muscle metaboreflex sensitivity in patients with OSA. This autonomic change associated with increased muscle blood flow may contribute to the increase in exercise performance in this set of patients.


Assuntos
Exercício , Músculo Esquelético/inervação , Apneia Obstrutiva do Sono/fisiopatologia , Sistema Nervoso Simpático/fisiologia , Teste de Esforço , Feminino , Antebraço/irrigação sanguínea , Hemodinâmica , Humanos , Contração Isométrica , Masculino , Pessoa de Meia-Idade , Reflexo , Fluxo Sanguíneo Regional
13.
Int J Cardiol ; 271: 54-59, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29861103

RESUMO

BACKGROUND: Changes in circulatory physiology are common in Fontan patients due to suboptimal cardiac output, which may reduce the peripheral blood flow and impair the skeletal muscle. The objective of this study was to investigate the forearm blood flow (FBF), cross-sectional area (CSA) of the thigh and functional capacity in asymptomatic clinically stable patients undergoing Fontan surgery. METHODS: Thirty Fontan patients and 27 healthy subjects underwent venous occlusion plethysmography, magnetic resonance imaging of the thigh musculature and maximal cardiopulmonary exercise testing. Muscle sympathetic nerve activity (MSNA), norepinephrine measures, cardiovascular magnetic resonance, handgrip strength and 6-minute walk test were also performed. RESULTS: Fontan patients have blunted FBF (1.59 ±â€¯0.33 vs 2.17 ±â€¯0.52 mL/min/100 mL p < 0.001) and forearm vascular conductance (FVC) (1.69 ±â€¯0.04 vs 2.34 ±â€¯0.62 units p < 0.001), reduced CSA of the thigh (81.2 ±â€¯18.6 vs 116.3 ±â€¯26.4 cm2p < 0.001), lower peak VO2 (29.3 ±â€¯6 vs 41.5 ±â€¯9 mL/kg/min p < 0.001), walked distance (607 ±â€¯60 vs 701 ±â€¯58 m p < 0.001) and handgrip strength (21 ±â€¯9 vs 30 ±â€¯8 kgf p < 0.001). The MSNA (30 ±â€¯4 vs 22 ±â€¯3 bursts/min p < 0.001) and norepinephrine concentration [265 (236-344) vs 222 (147-262) pg/mL p = 0.006] were also higher in Fontan patients. Multivariate linear regression showed FVC (ß = 0.653; CI = 0.102-1.205; p = 0.022) and stroke volume (ß = 0.018; CI = 0.007-0.029; p = 0.002) to be independently associated with reduced CSA of the thigh adjusted for body mass index. The CSA of the thigh adjusted for body mass index (ß = 5.283; CI = 2.254-8.312; p = 0.001) was independently associated with reduced peak VO2. CONCLUSION: Patients with Fontan operation have underdeveloped skeletal muscle with reduced strength that is associated with suboptimal peripheral blood supply and diminished exercise capacity.


Assuntos
Tolerância ao Exercício/fisiologia , Técnica de Fontan/tendências , Força da Mão/fisiologia , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Adolescente , Adulto , Estudos Transversais , Teste de Esforço/métodos , Teste de Esforço/tendências , Feminino , Seguimentos , Técnica de Fontan/efeitos adversos , Antebraço/irrigação sanguínea , Antebraço/diagnóstico por imagem , Antebraço/fisiologia , Capacidade Residual Funcional/fisiologia , Humanos , Masculino , Músculo Esquelético/irrigação sanguínea , Adulto Jovem
14.
J Renin Angiotensin Aldosterone Syst ; 19(2): 1470320318761725, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29629833

RESUMO

INTRODUCTION: Previous studies have linked angiotensin-converting enzyme ( ACE) insertion (I)/deletion (D) polymorphism (II, ID and DD) to physical performance. Moreover, ACE has two catalytic domains: NH2 (N) and COOH (C) with distinct functions, and their activity has been found to be modulated by ACE polymorphism. The aim of the present study is to investigate the effects of the interaction between aerobic exercise training (AET) and ACE I/D polymorphism on ACE N- and C-domain activities and vascular reactivity in humans. MATERIALS AND METHODS: A total of 315 pre-selected healthy males were genotyped for II, ID and DD genotypes. Fifty completed the full AET (II, n = 12; ID, n = 25; and DD, n = 13), performed in three 90-minute sessions weekly, in the four-month exercise protocol. Pre- and post-training resting heart rate (HR), peak O2 consumption (VO2 peak), mean blood pressure (MBP), forearm vascular conduction (FVC), total circulating ACE and C- and N-domain activities were assessed. One-way ANOVA and two -way repeated-measures ANOVA were used. RESULTS: In pre-training, all variables were similar among the three genotypes. In post-training, a similar increase in FVC (35%) was observed in the three genotypes. AET increased VO2 peak similarly in II, ID and DD (49±2 vs. 57±1; 48±1 vs. 56±3; and 48±5 vs. 58±2 ml/kg/min, respectively). Moreover, there were no changes in HR and MBP. The DD genotype was also associated with greater ACE and C-domain activities at pre- and post-training when compared to II. AET decreased similarly the total ACE and C-domain activities in all genotypes, while increasing the N-domain activity in the II and DD genotypes. However, interestingly, the measurements of N-domain activity after training indicate a greater activity than the other genotypes. These results suggest that the vasodilation in response to AET may be associated with the decrease in total ACE and C-domain activities, regardless of genotype, and that the increase in N-domain activity is dependent on the DD genotype. CONCLUSIONS: AET differentially affects the ACE C- and N-domain activities, and the N-domain activity is dependent on ACE polymorphism.


Assuntos
Vasos Sanguíneos/patologia , Exercício/fisiologia , Estudos de Associação Genética , Mutação INDEL/genética , Peptidil Dipeptidase A/química , Peptidil Dipeptidase A/genética , Polimorfismo Genético , Pressão Sanguínea/genética , Genótipo , Hemodinâmica , Humanos , Masculino , Consumo de Oxigênio , Peptidil Dipeptidase A/sangue , Domínios Proteicos , Adulto Jovem
16.
Am J Physiol Heart Circ Physiol ; 314(4): H878-H887, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29351461

RESUMO

Exercise training (ET) has emerged as a nonpharmacological therapy for cardiovascular diseases because of its helpful milieu for improving vascular function. The aim of the present study was to assess whether ET reverses the alterations in vascular reactivity observed in heart failure (HF)-related coronary arteries and to elucidate the molecular mechanisms involved in these adjustments. Male Wistar rats were subjected to either coronary artery ligation or sham operation. Four weeks after the surgery, rats were divided into two groups: untrained HF (UHF) and exercise-trained HF (THF). ET was conducted on a treadmill for 8 wk. An untrained SO group was included in the study as a normal control. ET restored the impaired acetylcholine (ACh)- and sodium nitroprusside-induced relaxation in coronary arteries to levels of the control. Oxidative stress and reduced nitric oxide (NO) production were observed in UHF, whereas ET restored both parameters to the levels of the control. Expression levels of endothelial NO synthase (eNOS) and soluble guanylyl cyclase subunits were increased in coronary arteries of UHF rats but reduced in THF rats. Tetrahydrobiopterin restored ACh-induced NO production in the UHF group, indicating that eNOS was uncoupled. ET increased the eNOS dimer-to-monomer ratio and expression of GTP cyclohydrolase 1, thus increasing NO bioavailability. Taken together, these findings demonstrate that ET reverses the dysfunction of the NO/soluble guanylyl cyclase pathway present in coronary arteries of HF rats. These effects of ET are associated with increased GTP cyclohydrolase 1 expression, restoration of NO bioavailability, and reduced oxidative stress through eNOS coupling. NEW & NOTEWORTHY The present study provides a molecular basis for the exercise-induced improvement in coronary arteries function in heart failure. Increasing the expression of GTP cyclohydrolase 1, the rate-limiting enzyme in the de novo biosynthesis of tetrahydrobiopterin, exercise training couples endothelial nitric oxide synthase, reduces oxidative stress, and increases nitric oxide bioavailability and sensitivity in coronary arteries of heart failure rats.


Assuntos
Vasos Coronários/enzimologia , Terapia por Exercício , Insuficiência Cardíaca/terapia , Óxido Nítrico Sintase Tipo III/metabolismo , Vasodilatação , Animais , Vasos Coronários/fisiopatologia , Modelos Animais de Doenças , Tolerância ao Exercício , GTP Cicloidrolase/metabolismo , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/fisiopatologia , Masculino , Óxido Nítrico/metabolismo , Estresse Oxidativo , Ratos Wistar , Transdução de Sinais , Guanilil Ciclase Solúvel/metabolismo
17.
Med Sci Sports Exerc ; 50(3): 596-602, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29040222

RESUMO

PURPOSE: Increased resting muscle sympathetic nerve activity (MSNA) and lower forearm blood flow (FBF) were observed in young men who use anabolic androgenic steroids (AAS). However, the response of MSNA and FBF in AAS users triggered by muscle mechanoreflex and central command has never been tested. In addition, we evaluated the blood pressure (BP) and heart rate (HR) responses during these maneuvers. METHODS: Nineteen AAS users (AASU) 31 ± 6 yr of age and 18 AAS nonusers (AASNU) 29 ± 4 yr of age were recruited. All participants were involved in strength training. AAS use was determined using a urine test (liquid chromatography with tandem mass spectrometry). MSNA was measured using the microneurography technique. FBF was measured by using venous occlusion plethysmography. BP was measured using an automatic oscillometric device. HR was recorded continuously through ECG. Isometric handgrip exercise was performed at 30% of the maximal voluntary contraction for 3 min, and mental stress was elicited by the Stroop color-word test for 4 min. RESULTS: The MSNA and FBF responses during exercise were similar between AASU and AASNU, with a trend toward higher MSNA (bursts per minute; P = 0.084) and lower forearm vascular conductance (FVC; units; P = 0.084) in AASU than in AASNU. During mental stress, AASU showed a significantly higher MSNA (P < 0.05) and lower FBF (P < 0.05) compared with AASNU. During both maneuvers, HR and BP increased linearly in both groups; however, AASU showed a significantly higher HR compared with AASNU. CONCLUSIONS: During muscle mechanoreflex activation (isometric exercise), AASU have normal MSNA and FBF responses, whereas during central command (mental stress) stimulation, AASU have exacerbated MSNA and blunted vasodilation. Therefore, mental stress seems to exacerbate neurovascular control throughout stress reaction situations in AASU.


Assuntos
Exercício/fisiologia , Hemodinâmica , Estresse Psicológico , Sistema Nervoso Simpático , Congêneres da Testosterona/administração & dosagem , Adulto , Pressão Sanguínea , Antebraço/irrigação sanguínea , Força da Mão , Frequência Cardíaca , Humanos , Masculino , Pletismografia , Fluxo Sanguíneo Regional , Vasodilatação
19.
Oxid Med Cell Longev ; 2017: 1549014, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29138674

RESUMO

We previously reported that aerobic exercise training (AET) consisted of 10 weeks of 60-min swimming sessions, and 5 days/week AET counteracts CH in obesity. Here, we evaluated the role of microRNAs and their target genes that are involved in heart collagen deposition and calcium signaling, as well as the cardiac remodeling induced by AET in obese Zucker rats. Among the four experimental Zucker groups: control lean rats (LZR), control obese rats (OZR), trained lean rats (LZR + TR), and trained obese rats (OZR + TR), heart weight was greater in the OZR than in the LZR group due to increased cardiac intramuscular fat and collagen. AET seems to exert a protective role in normalizing the heart weight in the OZR + TR group. Cardiac microRNA-29c expression was decreased in OZR compared with the LZR group, paralleled by an increase in the collagen volumetric fraction (CVF). MicroRNA-1 expression was upregulated while the expression of its target gene NCX1 was decreased in OZR compared with the LZR group. Interestingly, AET restored cardiac microRNA-1 to nonpathological levels in the OZR-TR group. Our findings suggest that AET could be used as a nonpharmacological therapy for the reversal of pathological cardiac remodeling and cardiac dysfunction in obesity.


Assuntos
Coração/fisiopatologia , MicroRNAs/metabolismo , Obesidade/genética , Obesidade/terapia , Condicionamento Físico Animal/fisiologia , Animais , Masculino , Obesidade/patologia , Obesidade/fisiopatologia , Ratos , Ratos Zucker
20.
Arq Bras Cardiol ; 109(2 Supl 1): 1-76, 2017 Jul.
Artigo em Português | MEDLINE | ID: mdl-28813069
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