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1.
Clin Biochem ; 117: 39-47, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35487256

RESUMO

The objective was to evaluate the analytical performance of a new point-of-need platform for rapid and accurate measurement of a host-protein score that differentiates between bacterial and viral infection. The system comprises a dedicated test cartridge (MeMed BV®) and an analyzer (MeMed Key®). In each run, three host proteins (TRAIL, IP-10 and CRP) are measured quantitatively and a combinational score (0-100) computed that indicates the likelihood of Bacterial versus Viral infection (BV score). Serum samples collected from patients with acute infection representing viral (0 ≤ score < 35), equivocal (35 ≤ score ≤ 65), or bacterial (65 < score ≤ 100) scores based on pre-defined score cutoffs were employed for the analytical evaluation studies as well as samples from healthy individuals. To assess reproducibility, triplicate runs were conducted at 3 different sites, on 2 analyzers per site over 5 non-consecutive days. Lower limit of quantitation (LLoQ) and analytical measurement range were established utilizing recombinant proteins. Sample stability was evaluated using patient samples representative of BV score range (0-100). MeMed Key® and MeMed BV® passed the acceptance criteria for each study. In the reproducibility study, TRAIL, IP-10 and CRP measurements ranged with coefficient of variation from 9.7 to 12.7%, 4.6 to 6.2% and 5.0 to 11.6%, respectively. LLoQ concentrations were established as 15 pg/mL, 100 pg/mL and 1 mg/L for TRAIL, IP-10 and CRP, respectively. In summary, the analytical performance reported here, along with diagnostic accuracy established in the Apollo clinical validation study (NCT04690569), supports that MeMed BV® run on MeMed Key® can serve as a tool to assist clinicians in differentiating between bacterial and viral infection.


Assuntos
Proteína C-Reativa , Viroses , Humanos , Reprodutibilidade dos Testes , Quimiocina CXCL10 , Viroses/diagnóstico
2.
PLoS One ; 16(1): e0245296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33434221

RESUMO

BACKGROUND: Treatment of severely ill COVID-19 patients requires simultaneous management of oxygenation and inflammation without compromising viral clearance. While multiple tools are available to aid oxygenation, data supporting immune biomarkers for monitoring the host-pathogen interaction across disease stages and for titrating immunomodulatory therapy is lacking. METHODS: In this single-center cohort study, we used an immunoassay platform that enables rapid and quantitative measurement of interferon γ-induced protein 10 (IP-10), a host protein involved in lung injury from virus-induced hyperinflammation. A dynamic clinical decision support protocol was followed to manage patients infected with severe acute respiratory syndrome coronavirus 2 and examine the potential utility of timely and serial measurements of IP-10 as tool in regulating inflammation. RESULTS: Overall, 502 IP-10 measurements were performed on 52 patients between 7 April and 10 May 2020, with 12 patients admitted to the intensive care unit. IP-10 levels correlated with COVID-19 severity scores and admission to the intensive care unit. Among patients in the intensive care unit, the number of days with IP-10 levels exceeding 1,000 pg/mL was associated with mortality. Administration of corticosteroid immunomodulatory therapy decreased IP-10 levels significantly. Only two patients presented with subsequent IP-10 flare-ups exceeding 1,000 pg/mL and died of COVID-19-related complications. CONCLUSIONS: Serial and readily available IP-10 measurements potentially represent an actionable aid in managing inflammation in COVID-19 patients and therapeutic decision-making. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04389645, retrospectively registered on May 15, 2020.


Assuntos
COVID-19/sangue , Quimiocina CXCL10/sangue , Sistemas de Apoio a Decisões Clínicas , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , COVID-19/patologia , COVID-19/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto
3.
Circulation ; 142(7): 670-683, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32475164

RESUMO

BACKGROUND: Recent evidence suggests that cancer and cardiovascular diseases are associated. Chemotherapy drugs are known to result in cardiotoxicity, and studies have shown that heart failure and stress correlate with poor cancer prognosis. However, whether cardiac remodeling in the absence of heart failure is sufficient to promote cancer is unknown. METHODS: To investigate the effect of early cardiac remodeling on tumor growth and metastasis colonization, we used transverse aortic constriction (TAC), a model for pressure overload-induced cardiac hypertrophy, and followed it by cancer cell implantation. RESULTS: TAC-operated mice developed larger primary tumors with a higher proliferation rate and displayed more metastatic lesions compared with controls. Serum derived from TAC-operated mice potentiated cancer cell proliferation in vitro, suggesting the existence of secreted tumor-promoting factors. Using RNA-sequencing data, we identified elevated mRNA levels of periostin in the hearts of TAC-operated mice. Periostin levels were also found to be high in the serum after TAC. Depletion of periostin from the serum abrogated the proliferation of cancer cells; conversely, the addition of periostin enhanced cancer cell proliferation in vitro. This is the first study to show that early cardiac remodeling nurtures tumor growth and metastasis and therefore promotes cancer progression. CONCLUSIONS: Our study highlights the importance of early diagnosis and treatment of cardiac remodeling because it may attenuate cancer progression and improve cancer outcome.


Assuntos
Cardiomegalia/metabolismo , Neoplasias Experimentais/metabolismo , Remodelação Ventricular , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Camundongos Transgênicos , Metástase Neoplásica , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , RNA-Seq
4.
PLoS One ; 14(2): e0213081, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30818334

RESUMO

c-Jun dimerization protein (JDP2) and Activating Transcription Factor 3 (ATF3) are closely related basic leucine zipper proteins. Transgenic mice with cardiac expression of either JDP2 or ATF3 showed maladaptive remodeling and cardiac dysfunction. Surprisingly, JDP2 knockout (KO) did not protect the heart following transverse aortic constriction (TAC). Instead, the JDP2 KO mice performed worse than their wild type (WT) counterparts. To test whether the maladaptive cardiac remodeling observed in the JDP2 KO mice is due to ATF3, ATF3 was removed in the context of JDP2 deficiency, referred as double KO mice (dKO). Mice were challenged by TAC, and followed by detailed physiological, pathological and molecular analyses. dKO mice displayed no apparent differences from WT mice under unstressed condition, except a moderate better performance in dKO male mice. Importantly, following TAC the dKO hearts showed low fibrosis levels, reduced inflammatory and hypertrophic gene expression and a significantly preserved cardiac function as compared with their WT counterparts in both genders. Consistent with these data, removing ATF3 resumed p38 activation in the JDP2 KO mice which correlates with the beneficial cardiac function. Collectively, mice with JDP2 and ATF3 double deficiency had reduced maladaptive cardiac remodeling and lower hypertrophy following TAC. As such, the worsening of the cardiac outcome found in the JDP2 KO mice is due to the elevated ATF3 expression. Simultaneous suppression of both ATF3 and JDP2 activity is highly beneficial for cardiac function in health and disease.


Assuntos
Fator 3 Ativador da Transcrição/deficiência , Proteínas Repressoras/deficiência , Remodelação Ventricular/fisiologia , Fator 3 Ativador da Transcrição/genética , Fator 3 Ativador da Transcrição/fisiologia , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Feminino , Fibrose , Coração/fisiopatologia , Mediadores da Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Contração Miocárdica/genética , Contração Miocárdica/fisiologia , Miocárdio/patologia , Proteínas Repressoras/genética , Proteínas Repressoras/fisiologia , Remodelação Ventricular/genética
5.
Altern Ther Health Med ; 23(2): 20-26, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28323625

RESUMO

Context • Menopause and obesity are associated with autonomic dysfunction. Unconventional exercise modalities that include an important flexibility component seem to improve cardiac autonomic function by lowering sympathetic tone and increasing vagal modulation of the heart rate (HR). Yet clear evidence of the effects of stretching training (ST) on cardiac autonomic modulation is limited. Objective • The present study intended to examine the effects of ST on HR variability (HRV) and flexibility in obese postmenopausal women. Design • The research team designed a randomized, controlled trial. Setting • The study was conducted at the Florida State University (Tallahassee, FL, USA). Participants • Twenty-four obese, postmenopausal women, aged 50-65 y with a body mass index of >30 but <40 kg/m2 participated in the study. Intervention • Participants were randomly assigned either to an ST group (n = 12) or a no-exercise control group (n = 12). The study was 8 wk in duration. Outcome Measures • Participant HRV and sit-and-reach scores (SRSs) were measured at baseline and after 8 wk of training. Results • Significant decreases occurred for the ST group between baseline and postintervention in sympathetic activity, as measured by normalized low frequency (nLF) power, and in sympathovagal balance, as measured by the ratio of the natural logarithm low frequency (LnLF) activity to the natural logarithm high frequency (LnHF) power, with P < .01 for both measures. The decreases for the ST group were significantly greater than those for the control group for the nLF and LnLF/LnHF, with P < .05 for both measures. Significant increases in vagal tone occurred for the ST group between baseline and postintervention, as measured by the normalized high frequency (nHF) power, with P < .01, and in SRS following ST, with P < .001. The increases for the ST group were significantly greater than those for the control group for the nHF and SRS, with P < .05 for both measures. The changes in SRS were correlated with the changes in the LnLF/LnHF power, with r = .65 and P < .03 negatively correlated. Conclusions • The findings indicated that ST can improve cardiac autonomic modulation by increasing vagal tone and decreasing sympathetic activity in obese postmenopausal women. The improvement in SRS partially explained the decrease in the sympathovagal balance. Because older or obese individuals have a higher risk of developing cardiovascular diseases, they could potentially benefit from ST.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Terapia por Exercício/métodos , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Obesidade/terapia , Exercício Pliométrico/métodos , Pós-Menopausa , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento , Sistema Vasomotor/fisiologia
6.
Cardiovasc Res ; 113(2): 134-146, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28082453

RESUMO

AIMS: Obesity and type 2 diabetes (T2D) trigger a harmful stress-induced cardiac remodeling process known as cardiomyopathy. These diseases represent a serious and widespread health problem in the Western world; however the underlying molecular basis is not clear. ATF3 is an 'immediate early' gene whose expression is highly and transiently induced in response to multiple stressors such as metabolic, oxidative, endoplasmic reticulum and inflammation, stressors that are involved in T2D cardiomyopathy. The role of ATF3 in diabetic cardiomyopathy is currently unknown. Our research has aimed to study the effect of ATF3 expression on cardiomyocytes, heart function and glucose homeostasis in an obesity-induced T2D mouse model. METHODS AND RESULTS: We used wild type mice (WT) as well as mutant mice with a cardiac-specific ATF3 deficiency (ATF3-cKO). Mice were fed a high-fat diet (HFD) for 15 weeks. HFD induced high ATF3 expression in cardiomyocytes. Mice were examined for cardiac remodeling processes and the diabetic state was assessed. HFD-fed ATF3-cKO mice exhibited severe cardiac fibrosis, higher levels of heart hypertrophic markers, increased inflammation and worse cardiac function, as compared to WT mice. Interestingly, HFD-fed ATF3-cKO mice display increased hyperglycemia and reduced glucose tolerance, despite higher blood insulin levels, as compared to HFD-fed WT mice. Elevated levels of the cardiac inflammatory cytokines IL-6 and TNFα leading to impaired insulin signalling may partially explain the peripheral glucose intolerance. CONCLUSIONS: Cardiac ATF3 has a protective role in dampening the HFD-induced cardiac remodeling processes. ATF3 exerts both local and systemic effects related to T2D-induced cardiomyopathy. This study provides a strong relationship between heart remodeling processes and blood glucose homeostasis.


Assuntos
Fator 3 Ativador da Transcrição/metabolismo , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Cardiomiopatias Diabéticas/sangue , Miócitos Cardíacos/metabolismo , Remodelação Ventricular , Fator 3 Ativador da Transcrição/deficiência , Fator 3 Ativador da Transcrição/genética , Animais , Cardiomegalia/sangue , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Células Cultivadas , Diabetes Mellitus Tipo 2/etiologia , Cardiomiopatias Diabéticas/etiologia , Cardiomiopatias Diabéticas/patologia , Cardiomiopatias Diabéticas/fisiopatologia , Dieta Hiperlipídica , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/farmacologia , Fibrose , Predisposição Genética para Doença , Homeostase , Mediadores da Inflamação/metabolismo , Insulina/sangue , Integrases/genética , Interleucina-6/sangue , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Cadeias Pesadas de Miosina/genética , Fenótipo , Regiões Promotoras Genéticas , Fator de Necrose Tumoral alfa/sangue , Remodelação Ventricular/efeitos dos fármacos
7.
Br J Nutr ; 116(2): 279-85, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27160957

RESUMO

Combined isometric exercise or metaboreflex activation (post-exercise muscle ischaemia (PEMI)) and cold pressor test (CPT) increase cardiac afterload, which may lead to adverse cardiovascular events. l-Citrulline supplementation (l-CIT) reduces systemic arterial stiffness (brachial-ankle pulse wave velocity (baPWV)) at rest and aortic haemodynamic responses to CPT. The aim of this study was to determine the effect of l-CIT on aortic haemodynamic and baPWV responses to PEMI+CPT. In all, sixteen healthy, overweight/obese males (age 24 (sem 6) years; BMI 29·3 (sem 4·0) kg/m2) were randomly assigned to placebo or l-CIT (6 g/d) for 14 d in a cross-over design. Brachial and aortic systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP), aortic augmented pressure (AP), augmentation index (AIx), baPWV, reflection timing (Tr) and heart rate (HR) were evaluated at rest and during isometric handgrip exercise (IHG), PEMI and PEMI+CPT at baseline and after 14 d. No significant effects were evident after l-CIT at rest. l-CIT attenuated the increases in aortic SBP and wave reflection (AP and AIx) during IHG, aortic DBP, MAP and AIx during PEMI, and aortic SBP, DBP, MAP, AP, AIx and baPWV during PEMI+CPT compared with placebo. HR and Tr were unaffected by l-CIT in all conditions. Our findings demonstrate that l-CIT attenuates aortic blood pressure and wave reflection responses to exercise-related metabolites. Moreover, l-CIT attenuates the exaggerated arterial stiffness response to combined metaboreflex activation and cold exposure, suggesting a protective effect against increased cardiac afterload during physical stress.


Assuntos
Aorta/efeitos dos fármacos , Citrulina/farmacologia , Temperatura Baixa , Exercício Físico/fisiologia , Músculo Esquelético/fisiologia , Obesidade/fisiopatologia , Estresse Fisiológico/efeitos dos fármacos , Adaptação Fisiológica/efeitos dos fármacos , Adulto , Aorta/fisiologia , Aorta/fisiopatologia , Pressão Arterial/efeitos dos fármacos , Suplementos Nutricionais , Humanos , Hipertensão/fisiopatologia , Isquemia/complicações , Isquemia/fisiopatologia , Masculino , Obesidade/complicações , Sobrepeso , Análise de Onda de Pulso , Estresse Fisiológico/fisiologia , Rigidez Vascular/efeitos dos fármacos , Adulto Jovem
8.
Am J Hypertens ; 28(11): 1332-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25904650

RESUMO

BACKGROUND: Overweight/obese young men have increased sympatho-excitation to cold and pain stress-induced by the cold pressor test (CPT) that may lead to abnormal hemodynamic responses. Concurrent CPT and exercise may augment the sympathetic-induced increases in aortic blood pressure (BP), pressure wave reflection (augmentation index, AIx), and arterial stiffness (pulse wave velocity, PWV). Since obesity is related with hypertension and sympathetic activity, we evaluated the aortic hemodynamic and PWV responses to muscle metaboreflex activation imposed by postexercise muscle ischemia (PEMI) concurrent with CPT in overweight/obese men. METHODS: In 16 healthy (body mass index >25 and <40kg/m(2)) men (24±2 years), heart rate (HR), brachial BP, aortic BP, augmented pressure (AP), AIx, AIx adjusted to 75 beats/min (AIx@75), reflection time (Tr), first (P1) and second systolic peak (P2, wave reflection magnitude), and PWV (brachial-ankle PWV, baPWV) were evaluated at baseline, during isometric-handgrip exercise (IHG), and PEMI with (PEMI + CPT) and without CPT. RESULTS: During IHG, brachial BP, aortic BP, AP, AIx, AIx@75, P1, and P2 increased ( P < 0.01) while Tr decreased ( P < 0.05) compared with baseline. During PEMI, all hemodynamic parameters remained elevated ( P < 0.05) and baPWV increased (P < 0.05) while Tr and HR returned to baseline. Compared with PEMI, the increases in HR, brachial BP, aortic BP, AIx@75, P1, P2, and baPWV were greater ( P < 0.05) during PEMI + CPT. During PEMI + CPT, Tr remained lower ( P < 0.05) than baseline. CONCLUSIONS: Cold exposure with concurrent metaboreflex activation induces a significant increase in aortic hemodynamics and arterial stiffness, which may explain the high risk of adverse cardiovascular events during physiological stress. CLINICAL TRIALS REGISTRATION: Trial Number NCT02104375.


Assuntos
Pressão Arterial/fisiologia , Temperatura Baixa , Exercício Físico/fisiologia , Hipertensão , Obesidade , Rigidez Vascular/fisiologia , Adulto , Aorta/fisiopatologia , Índice de Massa Corporal , Voluntários Saudáveis , Hemodinâmica/fisiologia , Humanos , Hipertensão/diagnóstico , Hipertensão/etiologia , Hipertensão/fisiopatologia , Masculino , Obesidade/complicações , Obesidade/diagnóstico , Obesidade/fisiopatologia , Estimulação Física/métodos , Análise de Onda de Pulso/métodos , Sistema Nervoso Simpático/fisiopatologia
9.
J Acad Nutr Diet ; 115(3): 369-377, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25578927

RESUMO

BACKGROUND: Postmenopausal women have a high prevalence of hypertension and often develop arterial stiffness thereby increasing cardiovascular disease risk. Although antihypertensive drug therapies exist, increasing numbers of people prefer natural therapies. In vivo studies and a limited number of clinical studies have demonstrated the antihypertensive and vascular-protective effects of blueberries. OBJECTIVE: To examine the effects of daily blueberry consumption for 8 weeks on blood pressure and arterial stiffness in postmenopausal women with pre- and stage 1-hypertension. DESIGN: This was an 8-week, randomized, double-blind, placebo-controlled clinical trial. PARTICIPANTS/SETTING: Forty-eight postmenopausal women with pre- and stage 1-hypertension recruited from the greater Tallahassee, FL, area participated. INTERVENTION: Participants were randomly assigned to receive either 22 g freeze-dried blueberry powder or 22 g control powder. MAIN OUTCOME MEASURES: Resting brachial systolic and diastolic blood pressures were evaluated and arterial stiffness was assessed using carotid-femoral pulse wave velocity and brachial-ankle pulse wave velocity. C-reactive protein, nitric oxide, and superoxide dismutase were measured at baseline, 4 weeks, and 8 weeks. STATISTICAL ANALYSES PERFORMED: Statistical analysis was performed using a split plot model of repeated measures analysis of variance. RESULTS: After 8 weeks, systolic blood pressure and diastolic blood pressure (131±17 mm Hg [P<0.05] and 75±9 mm Hg [P<0.01], respectively) and brachial-ankle pulse wave velocity (1,401±122 cm/second; P<0.01) were significantly lower than baseline levels (138±14 mm Hg, 80±7 mm Hg, and 1,498±179 cm/second, respectively), with significant (P<0.05) group×time interactions in the blueberry powder group, whereas there were no changes in the group receiving the control powder. Nitric oxide levels were greater (15.35±11.16 µmol/L; P<0.01) in the blueberry powder group at 8 weeks compared with baseline values (9.11±7.95 µmol/L), whereas there were no changes in the control group. CONCLUSIONS: Daily blueberry consumption may reduce blood pressure and arterial stiffness, which may be due, in part, to increased nitric oxide production.


Assuntos
Mirtilos Azuis (Planta) , Frutas , Hipertensão/dietoterapia , Idoso , Índice Tornozelo-Braço , Pressão Sanguínea/fisiologia , Proteína C-Reativa/metabolismo , Método Duplo-Cego , Feminino , Florida , Humanos , Hipertensão/sangue , Hipertensão/fisiopatologia , Pessoa de Meia-Idade , Óxido Nítrico/sangue , Análise de Onda de Pulso , Superóxido Dismutase/sangue , Rigidez Vascular/fisiologia
10.
Menopause ; 22(4): 423-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25225715

RESUMO

OBJECTIVE: High ankle systolic blood pressure (SBP; ≥175 mm Hg) is associated with arterial stiffness (pulse wave velocity [PWV]) and cardiac events. This study aims to investigate the effects of whole-body vibration (WBV) training on ankle SBP and its associations with changes in PWV and aortic SBP in postmenopausal women. METHODS: Thirty-six postmenopausal women were randomized to a control group (n = 12) or a WBV training group (3 d/wk) that was stratified by ankle SBP into WBV-high (n = 12) and WBV-normal (n = 12). Ankle SBP, brachial SBP, aortic SBP, femoral-ankle PWV (legPWV), carotid-femoral PWV, and brachial-ankle PWV (baPWV) were examined before and after 12 weeks. RESULTS: Baseline ankle SBP was higher (P < 0.05) in the WBV-high group compared with the WBV-normal group. WBV-high reduced mean (SEM) ankle SBP (-24 [7] mm Hg, P < 0.05) compared with WBV-normal and control. Both WBV groups decreased (P < 0.05) mean (SEM) brachial SBP (-11 [2] mm Hg), aortic SBP (-11 [3] mm Hg), legPWV (-0.80 [0.17] m/s), and baPWV (-1.18 [0.27] m/s) compared with the control group. Reductions in legPWV were correlated (P < 0.05) with decreases in ankle SBP (r = 0.43), brachial SBP (r = 0.42), aortic SBP (r = 0.42), and baPWV (r = 0.75). CONCLUSIONS: WBV training decreases ankle SBP in postmenopausal women with high ankle SBP. WBV training reduces aortic SBP, legPWV, and baPWV, but not carotid-femoral PWV, in postmenopausal women independently of ankle SBP. Therefore, reductions in peripheral and central SBP induced by WBV training are explained by a reduction in peripheral PWV.


Assuntos
Pressão Sanguínea/fisiologia , Exercício Físico , Hipertensão/terapia , Obesidade/terapia , Pós-Menopausa/fisiologia , Rigidez Vascular/fisiologia , Vibração/uso terapêutico , Índice Tornozelo-Braço/métodos , Feminino , Humanos , Hipertensão/fisiopatologia , Perna (Membro)/fisiopatologia , Pessoa de Meia-Idade , Obesidade/fisiopatologia
11.
Am J Hypertens ; 27(7): 899-906, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24572702

RESUMO

BACKGROUND: Cold-induced increases in aortic blood pressure (BP) may cause adverse cardiac events in hypertensives by increasing ventricular afterload. L-citrulline supplementation reduces BP at baseline and during the cold pressor test (CPT), but the effect on wave reflection (augmentation pressure (AP) and index (AIx)) is controversial. Our aim was to assess the effect of L-citrulline-rich watermelon supplementation on aortic hemodynamic responses to CPT in hypertensive adults. METHODS: Brachial systolic BP (bSBP) and aortic systolic BP (aSBP), AP, AIx, AIx adjusted to 75 beats/min (AIx75), reflection time (Tr), first (P1) and second systolic peak (P2; wave reflection magnitude), heart rate (HR), and systolic time index (STI; myocardial oxygen demand) at baseline and during CPT and magnitude of the response from baseline to CPT were evaluated in 13 individuals (10 women; 57±1 year; bSBP 151±5 mm Hg). Participants were randomized to a 6-week watermelon or placebo supplementation in a crossover design. RESULTS: Watermelon reduced (P < 0.05) bSBP, aSBP, P1, and P2 at baseline and CPT compared with placebo; thus, increases from baseline to CPT were unaffected. Watermelon did not affect AP, AIx, AIx75, and STI at baseline but decreased (P < 0.05) AP and STI during CPT and the increases in AP (~5mm Hg) and AIx75 (~7.3%) from baseline to CPT. CONCLUSIONS: Watermelon supplementation reduced aortic BP and myocardial oxygen demand during CPT and the magnitude of the cold-induced increase in wave reflection in obese adults with hypertension. Watermelon may provide cardioprotection by attenuating cold-induced aortic hemodynamic responses. CLINICAL TRIALS REGISTRATION: Clinicaltrial.gov register, NCT01185041.


Assuntos
Pressão Sanguínea/fisiologia , Citrullus , Hipertensão/fisiopatologia , Obesidade/fisiopatologia , Fitoterapia , Rigidez Vascular/efeitos dos fármacos , Artéria Braquial/fisiologia , Citrulina/farmacologia , Temperatura Baixa , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade
12.
Menopause ; 21(2): 131-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23715407

RESUMO

OBJECTIVE: The purpose of this study was to examine the impact of whole-body vibration (WBV) exercise training on arterial stiffness (pulse wave velocity [PWV]), blood pressure (BP), and leg muscle function in postmenopausal women. METHODS: Twenty-five postmenopausal women with prehypertension and hypertension (mean [SE]; age, 56 [1] y; systolic BP, 139 [2] mm Hg; body mass index, 34.7 [0.8] kg/m2) were randomized to 12 weeks of WBV exercise training (n = 13) or to the no-exercise control group. Systolic BP, diastolic BP, mean arterial pressure, heart rate, carotid-femoral PWV, brachial-ankle PWV, femoral-ankle PWV (legPWV), leg lean mass, and leg muscle strength were measured before and after 12 weeks. RESULTS: There was a group-by-time interaction (P < 0.05) for arterial stiffness, BP, and strength as brachial-ankle PWV (-1.3 [0.3] m/s, P < 0.01), legPWV (-0.81 [0.22] m/s, P < 0.01), systolic BP (-12 [3] mm Hg, P < 0.01), diastolic BP (-6 [2] mm Hg, P < 0.01), and mean arterial pressure (-9 [3] mm Hg, P < 0.01) decreased and as strength increased (21.0% [2.2%], P < 0.001) after WBV exercise training compared with no change after control. Heart rate decreased (-3 [1] beats/min, P < 0.05) after WBV exercise training, but there was no interaction (P > 0.05). Leg lean mass and carotid-femoral PWV were not significantly (P > 0.05) affected by WBV exercise training or control. CONCLUSIONS: Our findings indicate that WBV exercise training improves systemic and leg arterial stiffness, BP, and leg muscle strength in postmenopausal women with prehypertension or hypertension. WBV exercise training may decrease cardiovascular and disability risks in postmenopausal women by reducing legPWV and increasing leg muscle strength.


Assuntos
Exercício Físico , Hipertensão/terapia , Pós-Menopausa , Pré-Hipertensão/terapia , Rigidez Vascular , Vibração , Pressão Sanguínea , Índice de Massa Corporal , Feminino , Frequência Cardíaca , Humanos , Hipertensão/fisiopatologia , Perna (Membro)/irrigação sanguínea , Pessoa de Meia-Idade , Força Muscular , Obesidade/complicações , Obesidade/fisiopatologia , Pré-Hipertensão/fisiopatologia , Análise de Onda de Pulso
13.
Eur J Appl Physiol ; 114(1): 105-11, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24150784

RESUMO

PURPOSE: Impaired leg arterial stiffness (pulse wave velocity, PWV) and vasodilatory function are found after stroke. Acute passive vibration (PV) decreases leg PWV (legPWV) and pressure wave reflection (aortic augmentation index, aAIx) in healthy men. Our objective was to evaluate the effects of acute PV on aAIx and PWV in the paretic and non-paretic sides in stroke survivors. METHODS: Eleven stroke survivors (4 females) were randomized to either no-PV (control) or PV (25 Hz and 2 mm amplitude) trials on two separated visits. Following 20 min of supine rest with legs on a vibration platform, blood pressure, PWV, and aAIx were gathered before 10 continuous minutes of control or PV. Measurements were repeated at post-5, post-15, and post-30 min after control or PV. RESULTS: LegPWV and brachial-ankle PWV (baPWV, systemic stiffness) in paretic and non-paretic sides along with aAIx were significantly (P < 0.05) decreased from baseline at post-5 min after PV compared with control. At post-15 min, paretic and non-paretic legPWV remained significantly lower than baseline, but only non-paretic legPWV was different from control. We noted correlations between changes in paretic legPWV and changes in paretic baPWV (r = 0.47, P = 0.028) and aAIx (r = 0.51, P = 0.017) at post-5 min. CONCLUSIONS: Acute PV applied to the legs of stroke survivors reduces systemic arterial stiffness and aortic wave reflection due to a reduction in leg arterial stiffness, which last longer in the non-paretic than in the paretic leg.


Assuntos
Pressão Sanguínea , Reabilitação do Acidente Vascular Cerebral , Rigidez Vascular , Vibração/uso terapêutico , Adulto , Idoso , Estudos Cross-Over , Feminino , Humanos , Perna (Membro)/irrigação sanguínea , Perna (Membro)/fisiopatologia , Masculino , Pessoa de Meia-Idade , Análise de Onda de Pulso , Acidente Vascular Cerebral/fisiopatologia , Sobreviventes
14.
Am J Hypertens ; 27(3): 338-44, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24300595

RESUMO

BACKGROUND: Obesity and reduced muscle strength are associated with increased blood pressure (BP). We examined the impact of milk proteins and combined exercise training (CET) on BP, arterial function, and muscle strength (one-repetition maximum (1-RM)). METHODS: Thirty-three obese sedentary women (age = 30 ± 1 years; body mass index = 35.2 ± 0.9 kg/m(2); systolic BP (SBP) = 129 ± 2 mm Hg) were randomized to control carbohydrate (n = 11), whey (n = 11), and casein (n = 11) supplementation for 4 weeks. All participants performed moderate-intensity CET 3 days/week. Brachial and aortic SBP, augmentation index adjusted for 75 beats/minute (AIx@75), arterial stiffness (brachial-ankle pulse wave velocity (baPWV)), and 1-RM were measured before and after the interventions. RESULTS: There were significant (P < 0.05) time-by-group interactions for brachial SBP (bSBP), aortic SBP (aSBP), AIx@75, and baPWV. Whey and casein supplementation significantly (P < 0.05) decreased bSBP (approximately 5mm Hg for both), aSBP (approximately 7 mm Hg and approximately 6mm Hg, respectively), AIx@75 (approximately 9.2% and approximately 8.1%, respectively) and baPWV (approximately 57 cm/s and approximately 53 cm/s, respectively) compared with no changes in the control group. Upper- (approximately 22.2%) and lower-body 1-RM (approximately 44.0%) increased similarly in all groups. Changes in arterial function and 1-RM were not correlated. CONCLUSIONS: Milk protein supplementation with CET reduced SBP, wave reflection, and arterial stiffness in young obese women with prehypertension and hypertension. Because CET did not affect arterial function, milk proteins may have an antihypertensive effect by improving arterial function, as shown by reduced AIx@75 and baPWV. Muscle strength improvements after CET did not affect BP and arterial function. CLINICAL TRIAL REGISTRATION: ClinicalTrial.gov Registration NCT01830946.


Assuntos
Aorta/fisiopatologia , Caseínas/administração & dosagem , Suplementos Nutricionais , Hemodinâmica , Hipertensão/terapia , Proteínas do Leite/administração & dosagem , Obesidade/terapia , Treinamento Resistido , Rigidez Vascular , Adulto , Fatores Etários , Método Duplo-Cego , Feminino , Florida , Humanos , Hipertensão/complicações , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Força Muscular , Músculo Esquelético/fisiopatologia , Obesidade/complicações , Obesidade/diagnóstico , Obesidade/fisiopatologia , Análise de Onda de Pulso , Comportamento Sedentário , Fatores Sexuais , Fatores de Tempo , Resultado do Tratamento , Proteínas do Soro do Leite
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