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1.
J Am Geriatr Soc ; 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38864591

RESUMO

BACKGROUND: Persistent inflammation is associated with adverse health outcomes, but its impact on mortality has not been investigated previously among hip fracture patients. This article aims to investigate the influence of changes in levels of cytokines in the 2 months after a hip fracture repair on 5-year mortality. METHODS: This is a prospective cohort study from the Baltimore Hip Studies (BHS) with 191 community-dwelling older men and women (≥65 years) who had recently undergone surgical repair of an acute hip fracture, with recruitment from May 2006 to June 2011. Plasma interleukin-6 (IL-6), soluble tumor necrosis factor alpha receptor1 (sTNFα-R1), and interleukin-1 receptor agonist (IL-1RA) were obtained within 22 days of admission and at 2 months. All-cause mortality over 5 years was determined. Logistic regression analysis tested the associations between the cytokines' trajectories and mortality over 5 years, adjusted for covariates (age, sex, education, body mass index, lower extremity physical activities of daily living, and Charlson comorbidity index). RESULTS: High levels of IL-6 and sTNFα-R1 at baseline with small or no decline at 2 months were associated with higher odds of 5-year mortality compared with those with lower levels at baseline and greater decline at 2 months after adjustment for age, and other potential confounders (OR = 4.71, p = 0.01 for IL-6; OR = 15.03, p = 0.002 for sTNFα-R1). Similar results that failed to reach significance were found for IL-1RA (OR = 2.40, p = 0.18). Those with higher levels of cytokines at baseline with greater decline did not have significantly greater mortality than the reference group, those with lower levels at baseline and greater decline. CONCLUSION: Persistent elevation of plasma IL-6 and sTNFα-R1 levels within the first 2 months after hospital admission in patients with hip fracture is associated with higher 5-year mortality. These patients may benefit from enhanced care and earlier intensive interventions to reduce the risk of death.

2.
AIDS ; 38(6): 825-833, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38578959

RESUMO

OBJECTIVE: Understanding the physiological drivers of reduced cardiorespiratory fitness in people with HIV (PWH) will inform strategies to optimize healthspan. Chronotropic incompetence is common in heart failure and associated with low cardiorespiratory fitness yet is understudied in PWH. The objective was to determine the prevalence of chronotropic incompetence and its relationship with cardiorespiratory fitness. DESIGN: Participants were PWH at least 50 years of age with no prior history of heart failure or coronary heart disease who were enrolled in a randomized exercise trial. Baseline cardiopulmonary exercise testing (CPET) was used to measure cardiorespiratory fitness as peak oxygen consumption (VO2peak) and calculate the chronotropic index from heart rate values. Chronotropic incompetence was defined as an index less than 80%. RESULTS: The 74 participants were on average 61 years old, 80% Black or African American, and 93% men. Chronotropic incompetence was present in 31.1%. VO2peak was significantly lower among participants with chronotropic incompetence compared with participants without chronotropic incompetence [mean (SD) ml/min/kg: 20.9 (5.1) vs. 25.0 (4.5), P = 0.001]. Linear regression showed that chronotropic incompetence and age were independent predictors of VO2peak, but smoking and comorbidity were not. The chronotropic index correlated with VO2peak (r = 0.48, P < 0.001). CONCLUSION: Among older PWH without heart failure or coronary heart disease, chronotropic incompetence was present in approximately one-third of individuals and was associated with clinically relevant impaired cardiorespiratory fitness. Investigation of chronotropic incompetence in large cohorts which includes PWH and heart failure may contribute to strategies that promote healthy aging with HIV infection and offer a preclinical window for intervention.


Assuntos
Aptidão Cardiorrespiratória , Doença das Coronárias , Infecções por HIV , Insuficiência Cardíaca , Masculino , Humanos , Idoso , Pessoa de Meia-Idade , Feminino , Infecções por HIV/complicações , Teste de Esforço , Frequência Cardíaca/fisiologia
3.
Obesity (Silver Spring) ; 32(4): 667-677, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38414363

RESUMO

OBJECTIVE: The authors sought to understand sex differences in muscle metabolism in 73 older men and women. METHODS: Body composition, VO2max, and insulin sensitivity (M) by 3-hour hyperinsulinemic-euglycemic clamp with vastus lateralis muscle biopsies were measured. RESULTS: Women had lower body weight, VO2max, and fat-free mass than men. Men had lower M, lower change (insulin minus basal) in muscle glycogen synthase (GS) activity, and lower change in AKT protein expression than women. M was associated with the change (insulin-basal) in GS activity and the change in AKT protein expression. Sex differences (n = 60) were tested with 6-month weight loss or 3×/week aerobic exercise training. The postintervention minus preintervention change (insulin-basal) (∆∆) in GS activity (fractional, independent, total) was higher in men than women in the weight loss group and ∆∆ in GS fractional activity was higher in women than men in the aerobic exercise group. In all participants, ∆∆ in GS fractional and independent activities was related to ∆∆ in AKT expression and glycogen content. CONCLUSIONS: Sex differences in insulin sensitivity may be explained at the cellular muscle level, and to improve skeletal muscle insulin action in older adults, it may be necessary to recommend different behavioral strategies depending on the individual's sex.


Assuntos
Resistência à Insulina , Insulina , Feminino , Humanos , Masculino , Idoso , Insulina/metabolismo , Resistência à Insulina/fisiologia , Glicogênio Sintase/metabolismo , Caracteres Sexuais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Redução de Peso/fisiologia , Técnica Clamp de Glucose , Músculo Esquelético/metabolismo , Exercício Físico/fisiologia
4.
J Vasc Surg ; 79(2): 397-404, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37844848

RESUMO

OBJECTIVE: The aim of the present study was to develop a standardized contrast-enhanced duplex ultrasound (CE-DUS) protocol to assess lower-extremity muscle perfusion before and after exercise and determine relationships of perfusion with clinical and functional measures. METHODS: CE-DUS (EPIQ 5G, Philips) was used before and immediately after a 10-minute, standardized bout of treadmill walking to compare microvascular perfusion of the gastrocnemius muscle in older (55-82 years) patients with peripheral arterial disease (PAD) (n = 15, mean ankle-brachial index, 0.78 ± 0.04) and controls (n = 13). Microvascular blood volume (MBV) and microvascular flow velocity (MFV) were measured at rest and immediately following treadmill exercise, and the Modified Physical Performance Test (MPPT) was used to assess mobility function. RESULTS: In the resting state (pre-exercise), MBV in patients with PAD was not significantly different than normal controls (5.17 ± 0.71 vs 6.20 ± 0.83 arbitrary units (AU) respectively; P = .36); however, after exercise, MBV was ∼40% lower in patients with PAD compared with normal controls (5.85 ± 1.13 vs 9.53 ± 1.31 AU, respectively; P = .04). Conversely, MFV was ∼60% higher in patients with PAD compared with normal controls after exercise (0.180 ± 0.016 vs 0.113 ± 0.018 AU, respectively; P = .01). There was a significant between-group difference in the exercise-induced changes in both MBV and MFV (P ≤ .05). Both basal and exercise MBV directly correlated with MPPT score in the patients with PAD (r = 0.56-0.62; P < .05). CONCLUSIONS: This standardized protocol for exercise stress testing of the lower extremities quantifies calf muscle perfusion and elicits perfusion deficits in patients with PAD. This technique objectively quantifies microvascular perfusion deficits that are related to reduced mobility function and could be used to assess therapeutic efficacy in patients with PAD.


Assuntos
Teste de Esforço , Doença Arterial Periférica , Humanos , Idoso , Doença Arterial Periférica/diagnóstico por imagem , Extremidade Inferior , Músculo Esquelético/irrigação sanguínea , Perfusão
5.
Cancer Nurs ; 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38032743

RESUMO

BACKGROUND: Cancer-related fatigue is difficult to treat, and dietary interventions are promising yet underused. OBJECTIVE: We explored associations between dietary patterns and fatigue, and the effect of a dietary intervention versus control on fatigue using Women's Healthy Eating and Living study data, plus mediators and moderators of the intervention effect. METHODS: The Women's Healthy Eating and Living study was a randomized controlled trial among early-stage breast cancer survivors. The 4-year intervention encouraged fruits, vegetables, fiber, and 15% to 20% calories from fat. Fatigue outcomes included a 9-item energy scale and a single-item tiredness question. Dietary quality was estimated using a modified Healthy Eating Index (24-hour dietary recall) and serum carotenoid concentrations. Nutrient timing was obtained from 4-day food logs. RESULTS: Among 2914 total participants, lower body mass index was associated with less tiredness and more energy at baseline (P < .001 for both). Earlier start and end times for daily eating windows were associated with less tiredness (P = .014 and P = .027, respectively) and greater energy (P = .006 and P = .102, respectively). The intervention did not lead to improvements in fatigue on average (P > .125). However, the intervention was more effective for participants who were younger, had fewer comorbidities, and did not have radiation treatment. Mediators included increases in serum carotenoids, increases in the modified Healthy Eating Index, and weight loss/maintenance. CONCLUSION: Diet quality and earlier eating windows were associated with less fatigue. IMPLICATIONS FOR PRACTICE: Programs that encourage high diet quality and a morning meal and discourage nighttime eating should be tested for efficacy in reducing cancer-related fatigue in survivorship.

6.
J Appl Physiol (1985) ; 131(1): 56-63, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34013746

RESUMO

Low skeletal muscle capillarization is associated with impaired glucose tolerance (IGT); however, aerobic exercise training with weight loss (AEX + WL) increases skeletal muscle capillarization and improves glucose tolerance in adults with IGT. Given that the expression of angiogenic growth factors mediates skeletal muscle capillarization, we sought to determine whether angiogenic growth factor levels are associated with low capillarization in those with IGT versus normal glucose tolerance (NGT) or to the benefits of AEX + WL in both groups. Sixteen overweight or obese men 50-75 yr of age completed 6 mo of AEX + WL with oral glucose tolerance tests and vastus lateralis muscle biopsies for measurement of muscle vascular endothelial growth factor (VEGF), placental growth factor (PlGF), soluble fms-like tyrosine kinase receptor-1 (sFlt-1), and basic fibroblast growth factor (bFGF). At baseline, all growth factor levels were numerically lower in IGT than NGT, but these did not reach statistical significance (P = 0.06-0.33). Following AEX + WL, aerobic capacity [maximal oxygen consumption (V̇o2max)] increased by 16%, whereas body weight and 120-min postprandial glucose levels decreased by 10% and 15%, respectively (P ≤ 0.001 for all). There was a main effect of AEX + WL to increase VEGF (0.095 ± 0.016 vs. 0.114 ± 0.018 ng/µg, P < 0.05), PlGF (0.004 ± 0.001 vs. 0.005 ± 0.001 ng/µg, P < 0.05), and sFlt-1 (0.216 ± 0.029 vs. 0.264 ± 0.036 ng/µg, P < 0.01), with overall increases driven by the IGT group. These results suggest that 6 mo of AEX + WL increases skeletal muscle angiogenic growth factor levels in obese older adults with IGT and NGT, which may contribute to our previous findings that AEX + WL increases capillarization to improve glucose tolerance in those with IGT.NEW & NOTEWORTHY Skeletal muscle capillarization is lower in adults with impaired glucose tolerance than normal controls. This may, in part, be attributable to differential expression of angiogenic growth factors in skeletal muscle. Using a 6-mo aerobic exercise intervention with ∼10% body weight loss (AEX + WL), we show that the expression of angiogenic growth factors tends to be lower in adults with impaired glucose tolerance compared with normal controls and that AEX + WL increased expression of angiogenic growth factors in all participants.


Assuntos
Resistência à Insulina , Redução de Peso , Idoso , Indutores da Angiogênese , Exercício Físico , Feminino , Humanos , Masculino , Músculo Esquelético , Obesidade/terapia , Sobrepeso/terapia , Fator de Crescimento Placentário , Fator A de Crescimento do Endotélio Vascular
7.
Top Stroke Rehabil ; 28(4): 251-257, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32783602

RESUMO

BACKGROUND: Stroke survivors have exercise intolerance that contributes to reduced quality of life and survival. While exaggerated blood pressure responses during exercise have been documented in other chronic diseases, whether stroke patients have abnormal hemodynamic responses during aerobic exercise remains unexplored. OBJECTIVES: This cross-sectional study aimed to examine whether stroke survivors have exaggerated increases in blood pressure during maximal treadmill exercise and whether these responses may be related to systemic inflammation. METHODS: Forty-six participants (25 stroke survivors, STROKE, and 21 controls, CON) performed a maximal treadmill exercise test via the modified Naughton protocol while blood pressure was measured manually during each treadmill stage. A linear mixed model was used to compare the slope of rise in heart rate and blood pressure within and between groups. Spearmans rho analysis was performed to explore the relationship between these responses and circulating concentrations of inflammatory biomarkers. RESULTS: The STROKE group exhibited a lower VO2peak (16.4 ± 0.8 vs. 30.0 ± 1.8 ml/kg/min, P < .001) and a greater rate of increase in systolic blood pressure compared to CON (17.4 ± 1.5 vs. 9.9 ± 1.4 mmHg/stage, P < .001). We observed no relationship; however, between inflammatory biomarkers and the exaggerated hemodynamic responses in the STROKE group. CONCLUSION: In conclusion, stroke survivors exhibit greater increases in systolic blood pressure during maximal treadmill exercise compared to controls. These responses do not appear to be related to systemic inflammation. Future work should seek to delineate the mechanisms responsible for exaggerated blood pressure responses during exercise in stroke.


Assuntos
Teste de Esforço , Acidente Vascular Cerebral , Estudos Transversais , Exercício Físico , Humanos , Inflamação/etiologia , Qualidade de Vida , Acidente Vascular Cerebral/complicações , Sobreviventes
8.
JCSM Clin Rep ; 6(4): 137-142, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35311023

RESUMO

Background: Myostatin (MSTN) is a key negative regulator of muscle mass in humans and animals, having direct and indirect influences on molecular regulators of atrophy and hypertrophy, thus potentially impacting fitness and physical function. We have shown that myostatin is elevated in conditions of chronic disability (e.g. paretic limb of stroke). Our hypothesis is that myostatin would be elevated in older adults with sarcopenia. The purpose of this study was to examine the role of skeletal muscle myostatin in sarcopenia. Methods: Sixty-four overweight to obese aged 45-81 years underwent a maximal aerobic capacity (VO2max) test, dual-energy X-ray absorptiometry (DXA) scan to determine appendicular lean tissue (ALM), and vastus lateralis muscle biopsy to determine myostatin mRNA expression by quantitative real time PCR (Q-RT-PCR). Rates of sarcopenia were determined using (ALM/BMI), and sarcopenia was defined as <0.789 in men and <0.512 in women. Subjects had low fitness (VO2max: 22.7 ± 0.7 mL/kg/min) and on average 40.9 ± 1% body fat. Results: The prevalence of sarcopenia in this cohort was 16%. BMI, % body fat, and fat mass were higher in adults with sarcopenia than those without sarcopenia (all P < 0.001). Myostatin mRNA expression was lower in those without sarcopenia than those with sarcopenia (P < 0.05) and higher in men than women (P < 0.001). Myostatin expression was associated with BMI (r = 0.36, P < 0.01) and mid-thigh intramuscular fat (r = 0.29, P < 0.05). Conclusion: Given that myostatin is important in muscle atrophy, fat accumulation, and sarcopenia, further work could address its implication in other aging cohorts of disability and chronic disease.

10.
AIDS Res Hum Retroviruses ; 35(11-12): 999-1012, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456412

RESUMO

People aging with HIV (PAWH) infection experience greater impairments in physical and cognitive function, in addition to higher rates of peripheral comorbid conditions (e.g., renal failure, diabetes, bone fracture, hypertension, cardiovascular disease, polypharmacy, and multimorbidity). While multifactorial drivers, including HIV infection itself, antiretroviral therapy-related toxicities, disparities in care, and biobehavioral factors, likely contribute, there remains an overarching question as to what are the relevant age-related mechanisms and models that could inform interventions that promote health span and life span in PAWH? This workshop was convened to hear from experts on the biology of aging and HIV researchers studying PAWH to focus on advancing investigations at the interface of HIV and Aging. In this study, we summarize the discussions from the Harvard Center for AIDS Research and Boston Claude D. Pepper cosponsored workshop on HIV and Aging, which took place in October 2018.


Assuntos
Envelhecimento , Pesquisa Biomédica/organização & administração , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Idoso , Doenças Cardiovasculares/complicações , Cognição , Comorbidade , Congressos como Assunto , Idoso Fragilizado , Geriatria/métodos , Humanos , Hipertensão/complicações , Masculino
11.
PLoS One ; 13(6): e0198855, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29894513

RESUMO

BACKGROUND: HIV-infected adults have increased risk for age-related diseases and low cardiorespiratory fitness that can be prevented and improved with exercise. Yet, exercise strategies have not been well studied in older adults with HIV and may require substantial adaptation to this special population. OBJECTIVE: To determine the safety and efficacy of aerobic exercise in older HIV-infected men in a randomized trial comparing different levels of exercise intensity. METHODS: We conducted a pilot exercise trial in 22 HIV-infected men ≥50 years of age receiving antiretroviral therapy who were randomized 1:1 to moderate-intensity aerobic exercise (Mod-AEX) or high-intensity aerobic exercise (High-AEX) that was performed three times weekly for 16 weeks in a supervised setting. Primary outcome was cardiorespiratory fitness (VO2peak) measured by treadmill testing. Secondary outcomes were exercise endurance, six-minute walk distance (6-MWD), body composition measured by Dual-energy X-ray absorptiometry (DXA), and fasting plasma levels of lipids and glucose. RESULTS: VO2peak increased in the High-AEX group (3.6 ±1.2 mL/kg/min, p = 0.02) but not in the Mod-AEX group (0.4 ±1.4 mL/kg/min, p = 0.7) with a significant between group difference (p<0.01). Exercise endurance increased in both the High-AEX group (27 ±11%, p = 0.02) and the Mod-AEX group (11 ±4%, p = 0.04). The 6-MWD increased in both the High-AEX (62 ±18m, p = 0.01) and the Mod-AEX group (54 ±14m, p = 0.01). Changes in VO2peak and 6-MWD were clinically relevant. There were no serious exercise-related adverse events. Dropouts were similar between group (27% overall) and were related to joint pain. CONCLUSIONS: This pilot exercise trial demonstrates that moderate to high-intensity aerobic exercise in older HIV-infected men increases endurance and ambulatory function. However, increased cardiorespiratory fitness was observed only with high-intensity aerobic exercise despite substantial baseline impairment. Future research is needed to determine exercise strategies in older HIV-infected adults that address advanced aging and comorbidity yet are durable and feasible.


Assuntos
Envelhecimento , Terapia por Exercício , Exercício Físico/fisiologia , Infecções por HIV/terapia , Idoso , Teste de Esforço , Feminino , HIV/isolamento & purificação , Infecções por HIV/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
12.
Menopause ; 25(2): 211-216, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28832427

RESUMO

OBJECTIVE: Resistance training (RT) reduces fatigue and improves physical function and quality of life (QOL) in breast cancer survivors (BCS). This may be related to reductions in systemic and tissue-specific inflammation. This pilot study examines the hypothesis that RT induces changes in systemic and tissue-specific inflammation that contribute to improvements in physical and behavioral function in postmenopausal BCS. METHODS: Eleven BCS (60 ±â€Š2 years old, body mass index 30 ±â€Š1 kg/m, mean ±â€ŠSEM) underwent assessments of fatigue (Piper Fatigue Scale), physical function, QOL (SF-36), glucose and lipid metabolism, and systemic, skeletal muscle, and adipose tissue inflammation (n = 9) before and after 16 weeks of moderate-intensity whole-body RT. RESULTS: Muscle strength improved by 25% to 30% (P < 0.01), QOL by 10% (P = 0.04), chair stand time by 15% (P = 0.01), 6-minute walk distance by 4% (P = 0.03), and fatigue decreased by 58% (P < 0.01), fasting insulin by 18% (P = 0.04), and diastolic and systolic blood pressure by approximately 5% (P = 0.04) after RT. BCS with the worst fatigue and QOL demonstrated the greatest improvements (absolute change vs baseline: fatigue: r = -0.95, P < 0.01; QOL: r = -0.82, P < 0.01). RT was associated with an approximately 25% to 35% relative reduction in plasma and adipose tissue protein levels of proinflammatory interleukin (IL)-6sR, serum amyloid A, and tumor necrosis factor-α, and 75% relative increase in muscle pro-proliferative, angiogenic IL-8 protein content by 75% (all P < 0.05). BCS with the highest baseline proinflammatory cytokine levels had the greatest absolute reductions, and the change in muscle IL-8 correlated directly with improvements in leg press strength (r = 0.53, P = 0.04). CONCLUSIONS: These preliminary results suggest that a progressive RT program effectively lowers plasma and tissue-specific inflammation, and that these changes are associated with reductions in fatigue and improved physical and behavioral function in postmenopausal BCS.


Assuntos
Neoplasias da Mama/reabilitação , Fadiga/terapia , Inflamação/metabolismo , Inflamação/terapia , Treinamento Resistido , Idoso , Glicemia/metabolismo , Pressão Sanguínea , Composição Corporal , Sobreviventes de Câncer , Fadiga/fisiopatologia , Feminino , Humanos , Inflamação/fisiopatologia , Insulina/sangue , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Pessoa de Meia-Idade , Força Muscular/fisiologia , Projetos Piloto , Pós-Menopausa , Qualidade de Vida , Proteína Amiloide A Sérica/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Teste de Caminhada
13.
Artigo em Inglês | MEDLINE | ID: mdl-28691118

RESUMO

BACKGROUND: Contrast-Enhanced Ultrasonography (CEUS) is an imaging modality allowing perfusion quantification in targeted regions of interest of the lower extremity that has not been possible with color-flow imaging or with measurement of ankle brachial indices. We developed a protocol to quantify lower extremity muscle perfusion impairment in PAD patients in response to exercise. METHODS AND FINDINGS: Thirteen patients with Rutherford Class I-III Peripheral Arterial Disease (PAD) and no prior revascularization procedures were recruited from the Baltimore Veterans Affairs Medical Center and compared with eight control patients without PAD. CEUS interrogation of the index limb gastrocnemius muscle was performed using an intravenous bolus of lipid-stabilized microsphere contrast before and after a standardized treadmill protocol. Peak perfusion (PEAK) and time to peak perfusion (TTP) were measured before and after exercise. Between and within group differences were assessed. Control subjects demonstrated a more rapid TTP (p<0.01) and an increase in peak perfusion (PEAK, p=0.02) after exercise, when compared to their baseline measures. Patients with PAD demonstrated TTP and PEAK measures equivalent to controls at baseline (p=0.39, p=0.71, respectively). However, they exhibited no significant exercise-induced changes in perfusion (TTP p=0.49 and PEAK 0.67, respectively compared to baseline). After exercise, normal subjects had significantly shorter TTP (p=0.04) and greater PEAK (p=0.02) than PAD patients. CONCLUSION: Consistent with their lack of ischemic symptoms at rest, class I to III claudicant PAD patients showed similar perfusion measures (TTP and PEAK) at rest. PAD patients, however, were unable to increase perfusion in response to exercise, whereas controls increased perfusion significantly. This corresponds with claudication and limited walking capacity observed in PAD. CEUS with bolus injection offers a convenient, objective, quantitative and visual physiologic assessment of perfusion limitation in specific muscle groups of PAD patients. This has the potential for substantial clinical and research utility.

14.
J Stroke Cerebrovasc Dis ; 26(5): 962-968, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27955950

RESUMO

BACKGROUND: Peroxisome proliferator-activated receptor (PPAR)-γ coactivator (PGC-1α) gene and Sirtuin-1 (SIRT-1) respond to physiological stimuli and regulate insulin resistance. Inflammatory markers tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP), and the soluble forms of intracellular adhesion molecule (sICAM-1) and vascular CAM-1 (sVCAM-1) are associated with increased risk of diabetes and coronary heart disease. Resistive training (RT) reduces hyperinsulinemia and improves insulin action in chronic stroke. Yet, the molecular mechanisms for this are unknown. This study will determine the effects of RT on skeletal muscle PGC-1α and SIRT-1 mRNA expression and inflammatory and vascular markers. METHODS: Stroke survivors (50-76 years) underwent a fasting blood draw for measurement of TNF-α, IL-6, CRP, serum amyloid A, sICAM-1, sVCAM-1, and bilateral vastus lateralis biopsies before and after RT. Participants were also assessed using bilateral multislice thigh computed tomography scans from the knee to the hip, a total body scan by dual-energy X-ray absorptiometry, and 1-repetition maximum strength testing. Subjects performed 2 sets of 3 lower extremity RT exercises 3 times per week for 12 weeks. RESULTS: Bilateral leg press and leg extension strength increased ~30-50% with RT (P < .001). Body weight, total body fat mass, and fat-free mass did not change. Thigh muscle area and volume increased in both legs (P < .05). Nonparetic muscle PGC-1α mRNA expression increased 14% (P < .05) after RT and SIRT-1 mRNA decreased 24% (P < .05) and 31% (P < .01) in paretic and nonparetic muscles. There were no significant changes in plasma inflammation with training. DISCUSSION: RT in chronic stroke induces changes in key skeletal muscle regulators of metabolism, without effecting circulating inflammation.


Assuntos
Inflamação/terapia , Resistência à Insulina , Músculo Quadríceps/metabolismo , Treinamento Resistido , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/terapia , Absorciometria de Fóton , Adiposidade , Idoso , Biomarcadores/sangue , Biópsia , Glicemia/metabolismo , Doença Crônica , Citocinas/sangue , Feminino , Regulação da Expressão Gênica , Humanos , Inflamação/sangue , Inflamação/complicações , Inflamação/diagnóstico , Mediadores da Inflamação/sangue , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores , Contração Muscular , Força Muscular , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Músculo Quadríceps/diagnóstico por imagem , Músculo Quadríceps/fisiopatologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores de Risco , Sirtuína 1/genética , Sirtuína 1/metabolismo , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico , Resultado do Tratamento , Imagem Corporal Total
15.
Ethn Dis ; 26(4): 513-520, 2016 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-27773978

RESUMO

OBJECTIVE: After chemotherapy for breast cancer, Black women gain more weight and have an increased mortality rate compared with White women. Our study objective was to compare biomarkers associated with obesity in Black women with and without a history of breast cancer. DESIGN: Case-control. SETTING: Academic/federal institution. PARTICIPANTS: Black women with a history of breast cancer (cases) and age-matched controls. MAIN OUTCOME MEASURES: Insulin resistance (HOMA-IR); inflammation (TNF-α, IL-1b, IL-6, IL-8, CRP); lipids (cholesterol, triglycerides). METHODS: We compared insulin resistance, inflammation, and lipids in overweight and obese Black women with a history of breast cancer (n=19), age similar controls (n=25), and older controls (n=32). Groups did not differ on mean body mass index (BMI), which was 35.4 kg/m2, 36.0 kg/m2, and 33.0 kg/m2, respectively. RESULTS: Cases had 1.6 and 1.38 times higher HOMA-IR values compared with age similar and older controls, respectively (P≤.001 for both). TNF-α and IL-1b were significantly higher in cases compared with both control groups (P<.001 for both). IL-6 was also higher in cases compared with age-similar controls (P=.007), and IL-8 was lower in cases compared with older controls (P<.05). Lipids did not differ between cases and either control group. CONCLUSIONS: Black women with breast cancer were significantly more insulin resistant with increased inflammation compared not only with age similar controls but with women who were, on average, a decade older. These biomarkers of insulin resistance and inflammation may be associated with increased risk of breast cancer recurrence and require ongoing evaluation, especially given the relatively abnormal findings compared with the controls in this underserved group.


Assuntos
Negro ou Afro-Americano , Neoplasias da Mama/etnologia , Inflamação , Resistência à Insulina , Obesidade/etnologia , Adulto , Idoso , Biomarcadores , Índice de Massa Corporal , Peso Corporal , Neoplasias da Mama/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Lipídeos , Pessoa de Meia-Idade , Sobrepeso , Triglicerídeos , Fator de Necrose Tumoral alfa , População Branca
16.
Diabetol Metab Syndr ; 8: 44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27453736

RESUMO

OBJECTIVE: Breast cancer survivors (BCS) are at high risk for the development of obesity, type 2 diabetes mellitus, and metabolic syndrome. There is increasing interest in the association between depression and metabolic dysfunction, which is relevant in this population as depression is often present in the chronic phase of cancer recovery. Thus, the aim of this study was to evaluate metabolic risk in BCS with and without depression compared to non-cancer controls. METHODS: African American (46 %) and Caucasian (54 %) postmenopausal BCS (N = 28; age: 60 ± 2 years; mean ± SEM) were matched for race, age (±2 years), and BMI (±2 kg/m(2)) to non-cancer controls (N = 28). Center for Epidemiologic Studies Depression Scale (CES-D) >16 or antidepressant medication usage was used to classify depression. Metabolic status was defined by 2-hr glucose during an OGTT and classification of metabolic syndrome. RESULTS: Compared to non-cancer controls, BCS had similar 2-hr glucose, but higher fasting glucose and total cholesterol, and were 2.5 times more likely to have metabolic syndrome (21 vs. 52 %)(P's < 0.05). Conversely, HDL-C was 16 % higher in BCS (P < 0.05). Forty three % of BCS were on antidepressants compared to 14 % in non-cancer controls, despite similar mean CES-D scores (6 ± 1). Depressed BCS (46 %) had a higher BMI, waist circumference, fasting glucose, and more metabolic syndrome components than non-depressed BCS (P's < 0.05). CONCLUSIONS: BCS have a heightened prevalence of depression that may be associated with an increased prevalence of metabolic syndrome. These results support the need to monitor weight gain, depression, and the progression of metabolic abnormalities after cancer diagnosis and treatment. Further studies into the mechanistic link between depression and metabolic disease are necessary to identify strategies that can offset their impact on obesity and associated cardiovascular risk following a breast cancer diagnosis.

17.
Support Care Cancer ; 24(4): 1875-81, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26463645

RESUMO

PURPOSE: Women with higher body mass index (BMI) following breast cancer (BC) treatment are at higher risk of BC recurrence and death than women of normal weight. African American (AA) BC patients have the highest risk of BC recurrence and gain more weight after diagnosis than their white counterparts. The purpose of this study was to evaluate the association between a mindful eating intervention and weight loss in AA women following chemotherapy for BC. METHODS: A single-group 24-week longitudinal pilot study with repeated measures was conducted. AA women (N = 22, BMI = 35.13 kg/m(2), range = 27.08-47.21) with stage I-III BC who had finished active cancer treatment received a 12-week mindful eating intervention with individual dietary counseling and group mindfulness sessions, followed by bi-weekly telephone follow-up for 12 weeks. Linear mixed models were used to evaluate the effects of the intervention and of baseline mindfulness on the weight change over time. RESULTS: In the overall group (N = 22), MEQ scores increased over time (p = 0.001) while weight decreased over time (-0.887 kg, p = 0.015). Weight loss over time was associated with higher T1 MEQ scores (p = 0.043). Participants in the higher MEQ group (n = 11) at T1 experienced significant weight loss over time (-1.166 kg, p = 0.044), whereas those in the low MEQ (n = 11) did not lose weight. Participants who were diagnosed with stage 1 BC experienced significant weight loss over time (-7.909 kg, p = 0.014). CONCLUSIONS: This study suggests that a mindful weight loss program may be effective for weight reduction and maintenance in some AA women who have completed treatment for BC, particularly those diagnosed with stage 1 BC and with initially higher mindful eating behaviors. Mindful weight loss program is proposed as a promising way in which to reduce obesity-related conditions in AA BC survivors.


Assuntos
Neoplasias da Mama/terapia , Obesidade/terapia , Redução de Peso , Adulto , Negro ou Afro-Americano , Idoso , Índice de Massa Corporal , Neoplasias da Mama/psicologia , Dieta , Feminino , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Atenção Plena
18.
N Engl J Med ; 370(24): 2307-2315, 2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24848981

RESUMO

BACKGROUND: Lipolysis regulates energy homeostasis through the hydrolysis of intracellular triglycerides and the release of fatty acids for use as energy substrates or lipid mediators in cellular processes. Genes encoding proteins that regulate energy homeostasis through lipolysis are thus likely to play an important role in determining susceptibility to metabolic disorders. METHODS: We sequenced 12 lipolytic-pathway genes in Old Order Amish participants whose fasting serum triglyceride levels were at the extremes of the distribution and identified a novel 19-bp frameshift deletion in exon 9 of LIPE, encoding hormone-sensitive lipase (HSL), a key enzyme for lipolysis. We genotyped the deletion in DNA from 2738 Amish participants and performed association analyses to determine the effects of the deletion on metabolic traits. We also obtained biopsy specimens of abdominal subcutaneous adipose tissue from 2 study participants who were homozygous for the deletion (DD genotype), 10 who were heterozygous (ID genotype), and 7 who were noncarriers (II genotype) for assessment of adipose histologic characteristics, lipolysis, enzyme activity, cytokine release, and messenger RNA (mRNA) and protein levels. RESULTS: Carriers of the mutation had dyslipidemia, hepatic steatosis, systemic insulin resistance, and diabetes. In adipose tissue from study participants with the DD genotype, the mutation resulted in the absence of HSL protein, small adipocytes, impaired lipolysis, insulin resistance, and inflammation. Transcription factors responsive to peroxisome-proliferator-activated receptor γ (PPAR-γ) and downstream target genes were down-regulated in adipose tissue from participants with the DD genotype, altering the regulation of pathways influencing adipogenesis, insulin sensitivity, and lipid metabolism. CONCLUSIONS: These findings indicate the physiological significance of HSL in adipocyte function and the regulation of systemic lipid and glucose homeostasis and underscore the severe metabolic consequences of impaired lipolysis. (Funded by the National Institutes of Health and others).


Assuntos
Diabetes Mellitus Tipo 2/genética , Mutação da Fase de Leitura , Predisposição Genética para Doença , Lipólise/genética , Esterol Esterase/genética , Adulto , Idoso , Amish/genética , Diabetes Mellitus Tipo 2/metabolismo , Dislipidemias/genética , Dislipidemias/metabolismo , Feminino , Heterozigoto , Humanos , Resistência à Insulina/genética , Masculino , Redes e Vias Metabólicas/genética , Pessoa de Meia-Idade , Linhagem
19.
J Gerontol A Biol Sci Med Sci ; 69(7): 790-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24357038

RESUMO

The purpose of this study was to determine the effects of 6-month aerobic exercise training + weight loss (AEX + WL) on basal and insulin activation of glycogen synthase, basal citrate synthase activity, and Akt and AS160 phosphorylation in older, overweight/obese insulin-resistant men (n = 14; 63 ± 2 years; body mass index, 32 ± kg/m(2)). Muscle samples of the vastus lateralis were collected before and during a 3-hour 80 mU/m(2)/min hyperinsulinemic-euglycemic clamp. AEX + WL increased VO2max by 11% (p < .05) and decreased body weight (-9%, p < .001). AEX + WL increased basal citrate synthase activity by 46% (p < .01) and insulin activation of independent (2.9-fold) and fractional (2.3-fold) activities (both p < .001) of glycogen synthase. AEX + WL had no effect on phosphorylation of Akt or AS160. Glucose utilization (M) improved 25% (p < .01), and the change tended to be related to the increase in insulin activation of glycogen synthase fractional activity (r = .50, p = .08) following AEX + WL. In summary, AEX + WL has a robust effect on insulin activation of skeletal muscle glycogen synthase activity that likely contributes to improved glucose utilization in older insulin-resistant men.


Assuntos
Exercício Físico/fisiologia , Glicogênio Sintase/metabolismo , Resistência à Insulina/fisiologia , Músculo Esquelético/metabolismo , Redução de Peso/fisiologia , Idoso , Envelhecimento/fisiologia , Composição Corporal , Dieta Redutora , Proteínas Ativadoras de GTPase/metabolismo , Glucose/metabolismo , Técnica Clamp de Glucose , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-akt/metabolismo
20.
Nutr Health ; 21(2): 97-105, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23139389

RESUMO

Breast cancer survival rates are lower in African Americans (AAs) than in Caucasians, owing in part to a higher prevalence of obesity in the former, which increases the risk of recurrence and mortality. The Women's Intervention Nutrition Study (WINS) found that Caucasian women who followed a low-fat eating plan experienced a lower rate of cancer recurrence than women who maintained their usual diets. The purpose of this study was to test the feasibility of a WINS plan tailored to the cultural needs of AA breast cancer survivors. This feasibility pilot study was conducted at a university National Cancer Institute-designated comprehensive cancer center outpatient clinic with AA breast cancer survivors. The culturally specific WINS (WINS-c) plan included eight individual counseling sessions, five educational group meetings, and follow-up telephone calls over a 1-year period. Outcome measures included dietary fat, triglyceride, insulin and glucose levels, and fruit and vegetable intake. Participants (n = 8) had a mean age of 61.1 years (standard error of the mean (SEM) 3.1 years) and a mean BMI of 32 kg/m(2) (SEM 4.25 kg/m)(2). Baseline daily fat consumption decreased from 64.6 g (range 36.8-119.6g) to 44.0 g (21.6-73.4g) at 52 weeks (p = 0.07). Mean daily consumption of fruits and vegetables increased by 36% and 15%, respectively. Mean triglyceride levels decreased at 12 months (p < 0.05). Sustained hyperinsulinemia was noted in most participants, including those without diabetes. Mean calcium and vitamin D consumption decreased over the 1-year study period. In AA breast cancer survivors, the WINS-c program resulted in a trend toward reduced fat consumption and may represent a sustainable approach in this population for improvement of diet quality after breast cancer.


Assuntos
Neoplasias da Mama/prevenção & controle , Dieta com Restrição de Gorduras/métodos , Comportamento Alimentar/etnologia , Sobreviventes , Aumento de Peso , Negro ou Afro-Americano , Idoso , Glicemia , Índice de Massa Corporal , Neoplasias da Mama/sangue , Neoplasias da Mama/etnologia , Aconselhamento/métodos , Cultura , Gorduras na Dieta/administração & dosagem , Estudos de Viabilidade , Feminino , Seguimentos , Frutas , Humanos , Insulina/sangue , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Educação de Pacientes como Assunto/métodos , Triglicerídeos/sangue , Verduras
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