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1.
Front Physiol ; 14: 1199763, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520827

RESUMO

The purpose of this secondary analysis was to determine what portion of the effects of a Diabetes Prevention Program-like intervention on metabolic syndrome (MetS) could be achieved with exercise alone, as well as to determine the relative importance of exercise intensity and amount to the total exercise effect on MetS. Sedentary, overweight adults with prediabetes were randomly assigned to one of four 6-month interventions: 1) low-amount/moderate-intensity (10 kcal/kg/week at 50% peak V˙O2); 2) high-amount/moderate-intensity (16 kcal/kg/week at 50% peak V˙O2); 3) high-amount/vigorous-intensity (16 kcal/kg/week at 75% peak V˙O2); or 4) diet (7% weight loss) plus low-amount/moderate-intensity (10 kcal/kg/week at 50% peak V˙O2). The primary outcome of this secondary analysis was change in the MetS z-score. A total of 130 participants had complete data for all five Adult Treatment Panel (ATP) III MetS criteria. The diet-and-exercise group statistically outperformed the MetS z-score and the ATP III score compared to the exercise alone group. Aerobic exercise alone achieved 24%-50% of the total effect of the combined diet-and-exercise intervention on the MetS score. Low-amount moderate-intensity exercise quantitatively performed equal to or better than the interventions of high-amount moderate-intensity or high-amount vigorous-intensity exercise in improving the MetS score. The combined diet-and-exercise intervention remains more efficacious in improving the MetS z-score. However, all three exercise interventions alone showed improvements in the MetS z-score, suggesting that a modest amount of moderate-intensity exercise is all that is required to achieve approximately half the effect of a diet-and-exercise intervention on the MetS. Clinical Trial Registration: clinicaltrials.gov, identifier NCT00962962.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35086944

RESUMO

INTRODUCTION: To determine the relative contributions of various amounts and intensities of exercise alone to a combined lifestyle intervention on health-related quality of life (HrQoL) measures. RESEARCH DESIGN AND METHODS: Participants (n=162) were sedentary, overweight/obese, with pre-diabetes, and randomized to one of four 6-month interventions: (1) high amount/moderate intensity exercise-energy expenditure of 16 kcal/kg of body weight/week (KKW) at 50% oxygen consumption (V̇O2) reserve; (2) high/vigorous-16 KKW at 75% V̇O2 reserve; (3) low/moderate-10 KKW at 50% V̇O2 reserve; (4) low/moderate plus diet-10 KKW at 50% V̇O2 reserve plus a calorically restricted diet. The 36-Item Short-Form Survey (SF-36) and Satisfaction with Physical Function and Appearance (SPF/SPA) survey were assessed at baseline and post-intervention. Analyses of covariance determined differences in change scores among groups (p<0.05). Paired t-tests determined significant pre-intervention versus post-intervention scores within groups (p<0.05). RESULTS: Across the intervention, all groups (p<0.05) improved the physical component, SPF, and SPA scores. Only the low/moderate/diet group (p<0.001) significantly improved the mental component score. The high/vigorous group achieved 84.5% of the low/moderate/diet group effect for change in physical component score, and the low/moderate group achieved 83.7% of the low/moderate/diet group effect for change in mental component score. CONCLUSIONS: In general, a low amount of moderate intensity exercise combined with diet was the most effective intervention for improving HrQoL. Of the exercise-only interventions, vigorous intensity exercise provided the greatest impact on changes in physical function. On the other hand, low amounts of moderate intensity exercise provided the greatest impact on mental well-being, potentially being a more attainable exercise dose for previously sedentary individuals with pre-diabetes to achieve.


Assuntos
Exercício Físico , Qualidade de Vida , Dieta , Humanos , Estilo de Vida , Obesidade/terapia
3.
Front Immunol ; 11: 729, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431698

RESUMO

Neutrophil dysfunction is a common feature of aging, and is associated with the pathogenesis of many age-related diseases, including type 2 diabetes mellitus (T2DM). Although exercise training improves metabolic health, decreases risk of T2DM, and is associated with improving neutrophil functions, involvement in regular physical activity declines with age. The aim of this study was to determine if neutrophil functions could be improved in association with changes in fitness and metabolic parameters in older adults at risk for T2DM using 10-weeks of low volume high-intensity interval exercise training (HIIT). Ten older (71 ± 5 years) sedentary adults with prediabetes (HbA1c: 6.1 ± 0.3%) completed 10 weeks of a supervised HIIT program. Three 30 min sessions/week consisted of ten 60 s intervals of low intensity [50-60% heart rate reserve (HRR)] separated with similar durations of high intensity intervals (80-90% HRR). Before and after training, glucose and insulin sensitivity, neutrophil chemotaxis, bacterial phagocytosis, reactive oxygen species (ROS) production, and mitochondrial functions were assessed. Exercise-mediated changes in cardiorespiratory fitness (VO2peak) and neutrophil functions were compared to six young (23 ± 1 years) healthy adults. Following training, significant reductions in fasting glucose and insulin were accompanied by improved glucose control and insulin sensitivity (all p < 0.05). Before exercise training, VO2peak in the old participants was significantly less than that of the young controls (p < 0.001), but increased by 16 ± 11% following training (p = 0.002) resulting in a 6% improvement of the deficit. Neutrophil chemotaxis, phagocytosis and stimulated ROS production were significantly less than that of the young controls, while basal ROS were higher before training (all p < 0.05). Following training, chemotaxis, phagocytosis and stimulated ROS increased while basal ROS decreased, similar to levels observed in the young controls (all p < 0.05) and reducing the deficit of the young controls between 2 and 154%. In five of the adults with prediabetes, neutrophil mitochondrial functions were significantly poorer than the six young controls before training. Following training, mitochondrial functions improved toward those observed in young controls (all p < 0.05), reducing the deficit of the young controls between 14.3 and 451%. Ten weeks of HIIT in older adults at risk for T2DM reduced disease risk accompanied by improved primary and bioenergetic neutrophil functions. Our results are consistent with a reduced risk of infections mediated by relationships in exercise induced systemic and cellular metabolic features. Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT02441205, registered on May 12th, 2015.


Assuntos
Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/reabilitação , Terapia por Exercício/métodos , Treinamento Intervalado de Alta Intensidade/métodos , Neutrófilos/imunologia , Estado Pré-Diabético/imunologia , Estado Pré-Diabético/reabilitação , Rejuvenescimento , Caminhada , Idoso , Envelhecimento/imunologia , Movimento Celular/imunologia , Diabetes Mellitus Tipo 2/sangue , Feminino , Hemoglobinas Glicadas/análise , Humanos , Masculino , Projetos Piloto , Estado Pré-Diabético/sangue , Risco , Resultado do Tratamento , Adulto Jovem
4.
Front Sports Act Living ; 2: 620300, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33644749

RESUMO

Purpose: The main purpose of this study was to determine the differential effects of aerobic training (AT), resistance training (RT), and a combination of aerobic and resistance training (AT/RT) on changes in self-rated HrQoL measures, including the Short-Form 36 (SF-36) survey and Satisfaction with Physical Function and Appearance survey. We also sought to determine if combination training (AT/RT) has a more or less additive effect compared to AT or RT alone on self-rated HrQoL measures. Materials and Methods: Participants (n = 137) completed one of three 8-month exercise interventions: (1) AT: 14 kcal exercise expenditure per kg of body weight per week (KKW; equivalent to roughly 12 miles/week) at 65-80% of peak oxygen consumption; (2) RT: 3 days per week, 8 exercises, 3 sets per exercise, 8-12 repetitions per set; (3) AT/RT: full combination of the AT and RT interventions. The SF-36 survey, Satisfaction with Physical Function and Appearance survey, physical fitness, and anthropometrics were assessed at baseline and post-intervention. Paired t-tests determined significant pre- vs. post-intervention scores within groups (p < 0.05). Analyses of covariance determined differences in change scores among groups (p < 0.05). Results: On average, participants were 49.0 ± 10.6 years old, obese (BMI: 30.6 ± 3.2 kg/m2), female (57.7%), and Caucasian (84.7%). Following the 8-month intervention, exercise groups improved peak VO2 (all groups), strength (RT and AT/RT), and anthropometric measures (AT and AT/RT). For the SF-36, RT (p = 0.03) and AT/RT (p < 0.001) significantly improved their physical component score; only AT/RT (p < 0.001) significantly improved their mental component score. Notably, all groups significantly improved both their satisfaction with physical function and appearance scores (All Groups: p < 0.001 for both outcomes). Conclusions: We found that aerobic, resistance, or combination exercise training improves several components of self-rated HrQoL, including physical function, appearance, and mental well-being. Clinical Trial Registration: No. NCT00275145.

5.
Am J Cardiol ; 124(5): 655-660, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31296368

RESUMO

Ranolazine reduces angina frequency and increases exercise capacity. We hypothesized that exercise training with ranolazine would allow subjects to train at greater intensities, resulting in greater improvements in exercise capacity, physical activity, and health-related quality of life (HRQOL). In a pilot study, subjects with chronic stable angina pectoris were randomized to ranolazine (n = 13) or placebo (n = 16). After a 2-week drug titration period, subjects participated in a 12-week exercise program. Peak VO2, physical activity (via accelerometer), and HRQOL were assessed before and after training. After exercise training, peak VO2increased twice as much with ranolazine (2.1 ± 3.4 ml/kg/min) as with placebo (0.9 ± 1.5) (both p <0.05). After exercise training, both groups significantly improved HRQOL score (p <0.05); however, the improvement with ranolazine (19 ± 21) was almost 50% greater than with placebo (13 ± 18). There was a significant decrease in maximal heart rate after training with ranolazine but not with placebo (group difference, p = 0.04). Oxygen pulse (peak VO2/peak HR) increased in both groups after training; but, the increase was 4 times greater with ranolazine - resulting in a significant difference between groups (p = 0.044). In conclusion, patients with angina, the addition of ranolazine to an exercise program may improve aerobic fitness, physical activity, and HRQOL beyond the results of an exercise training program alone. Exercise training with ranolazine led to significantly greater increases in oxygen pulse, which is significantly correlated with stroke volume and is an independent predictor of mortality.


Assuntos
Atividades Cotidianas , Angina Estável/tratamento farmacológico , Angina Estável/reabilitação , Terapia por Exercício/métodos , Qualidade de Vida , Ranolazina/uso terapêutico , Idoso , Angina Estável/diagnóstico , Fármacos Cardiovasculares/uso terapêutico , Doença Crônica , Terapia Combinada , Método Duplo-Cego , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oximetria , Consumo de Oxigênio/efeitos dos fármacos , Projetos Piloto , Valor Preditivo dos Testes , Resultado do Tratamento
6.
Arthritis Res Ther ; 20(1): 283, 2018 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-30587230

RESUMO

BACKGROUND: Sarcopenic obesity, associated with greater risk of cardiovascular disease (CVD) and mortality in rheumatoid arthritis (RA), may be related to dysregulated muscle remodeling. To determine whether exercise training could improve remodeling, we measured changes in inter-relationships of plasma galectin-3, skeletal muscle cytokines, and muscle myostatin in patients with RA and prediabetes before and after a high-intensity interval training (HIIT) program. METHODS: Previously sedentary persons with either RA (n = 12) or prediabetes (n = 9) completed a 10-week supervised HIIT program. At baseline and after training, participants underwent body composition (Bod Pod®) and cardiopulmonary exercise testing, plasma collection, and vastus lateralis biopsies. Plasma galectin-3, muscle cytokines, muscle interleukin-1 beta (mIL-1ß), mIL-6, mIL-8, muscle tumor necrosis factor-alpha (mTNF-α), mIL-10, and muscle myostatin were measured via enzyme-linked immunosorbent assays. An independent cohort of patients with RA (n = 47) and age-, gender-, and body mass index (BMI)-matched non-RA controls (n = 23) were used for additional analyses of galectin-3 inter-relationships. RESULTS: Exercise training did not reduce mean concentration of galectin-3, muscle cytokines, or muscle myostatin in persons with either RA or prediabetes. However, training-induced alterations varied among individuals and were associated with cardiorespiratory fitness and body composition changes. Improved cardiorespiratory fitness (increased absolute peak maximal oxygen consumption, or VO2) correlated with reductions in galectin-3 (r = -0.57, P = 0.05 in RA; r = -0.48, P = 0.23 in prediabetes). Training-induced improvements in body composition were related to reductions in muscle IL-6 and TNF-α (r < -0.60 and P <0.05 for all). However, the association between increased lean mass and decreased muscle IL-6 association was stronger in prediabetes compared with RA (Fisher r-to-z P = 0.0004); in prediabetes but not RA, lean mass increases occurred in conjunction with reductions in muscle myostatin (r = -0.92; P <0.05; Fisher r-to-z P = 0.026). Subjects who received TNF inhibitors (n = 4) or hydroxychloroquine (n = 4) did not improve body composition with exercise training. CONCLUSION: Exercise responses in muscle myostatin, cytokines, and body composition were significantly greater in prediabetes than in RA, consistent with impaired muscle remodeling in RA. To maximize physiologic improvements with exercise training in RA, a better understanding is needed of skeletal muscle and physiologic responses to exercise training and their modulation by RA disease-specific features or pharmacologic agents or both. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02528344 . Registered on August 19, 2015.


Assuntos
Artrite Reumatoide/fisiopatologia , Treinamento Intervalado de Alta Intensidade/métodos , Músculo Esquelético/fisiopatologia , Estado Pré-Diabético/fisiopatologia , Idoso , Artrite Reumatoide/sangue , Artrite Reumatoide/terapia , Índice de Massa Corporal , Estudos Transversais , Exercício Físico/fisiologia , Terapia por Exercício/métodos , Feminino , Galectina 3/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/sangue , Estado Pré-Diabético/terapia
7.
Arthritis Res Ther ; 20(1): 127, 2018 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-29898765

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory disease in which adults have significant joint issues leading to poor health. Poor health is compounded by many factors, including exercise avoidance and increased risk of opportunistic infection. Exercise training can improve the health of patients with RA and potentially improve immune function; however, information on the effects of high-intensity interval training (HIIT) in RA is limited. We sought to determine whether 10 weeks of a walking-based HIIT program would be associated with health improvements as measured by disease activity and aerobic fitness. Further, we assessed whether HIIT was associated with improved immune function, specifically antimicrobial/bacterial functions of neutrophils and monocytes. METHODS: Twelve physically inactive adults aged 64 ± 7 years with either seropositive or radiographically proven (bone erosions) RA completed 10 weeks of high-intensity interval walking. Training consisted of 3 × 30-minute sessions/week of ten ≥ 60-second intervals of high intensity (80-90% VO2reserve) separated by similar bouts of lower-intensity intervals (50-60% VO2reserve). Pre- and postintervention assessments included aerobic and physical function; disease activity as measured by Disease Activity score in 28 joints (DAS28), self-perceived health, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR); plasma interleukin (IL)-1ß, IL-6, chemokine (C-X-C motif) ligand (CXCL)-8, IL-10, and tumor necrosis factor (TNF)-α concentrations; and neutrophil and monocyte phenotypes and functions. RESULTS: Despite minimal body composition change, cardiorespiratory fitness increased by 9% (change in both relative and absolute aerobic capacity; p < 0.001), and resting blood pressure and heart rate were both reduced (both p < 0.05). Postintervention disease activity was reduced by 38% (DAS28; p = 0.001) with significant reductions in ESR and swollen joints as well as improved self-perceived health. Neutrophil migration toward CXCL-8 (p = 0.003), phagocytosis of Escherichia coli (p = 0.03), and ROS production (p < 0.001) all increased following training. The frequency of cluster of differentiation 14-positive (CD14+)/CD16+ monocytes was reduced (p = 0.002), with both nonclassical (CD14dim/CD16bright) and intermediate (CD14bright/CD16positive) monocytes being reduced (both p < 0.05). Following training, the cell surface expression of intermediate monocyte Toll-like receptor 2 (TLR2), TLR4, and HLA-DR was reduced (all p < 0.05), and monocyte phagocytosis of E. coli increased (p = 0.02). No changes were observed for inflammatory markers IL-1ß, IL-6, CXCL-8, IL-10, CRP, or TNF-α. CONCLUSIONS: We report for the first time, to our knowledge, that a high-intensity interval walking protocol in older adults with stable RA is associated with reduced disease activity, improved cardiovascular fitness, and improved innate immune functions, indicative of reduced infection risk and inflammatory potential. Importantly, the exercise program was well tolerated by these patients. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02528344 . Registered on 19 August 2015.


Assuntos
Artrite Reumatoide/terapia , Terapia por Exercício/métodos , Treinamento Intervalado de Alta Intensidade/métodos , Imunidade Inata/fisiologia , Caminhada/fisiologia , Idoso , Artrite Reumatoide/imunologia , Artrite Reumatoide/fisiopatologia , Citocinas/sangue , Escherichia coli/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/imunologia , Fagocitose/imunologia , Projetos Piloto , Índice de Gravidade de Doença
8.
J Virol ; 92(3)2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29142135

RESUMO

During the infection cycle of Autographa californica multiple nucleopolyhedrovirus (AcMNPV), two forms of virions are produced, budded virus (BV) and occlusion-derived virus (ODV). Nucleocapsids that form BV have to egress from the nucleus, whereas nucleocapsids that form ODV remain inside the nucleus. The molecular mechanism that determines whether nucleocapsids remain inside or egress from the nucleus is unknown. AC141 (a predicted E3 ubiquitin ligase) and viral ubiquitin (vUbi) have both been shown to be required for efficient BV production. In this study, it was hypothesized that vUbi interacts with AC141, and in addition, that this interaction was required for BV production. Deletion of both ac141 and vubi restricted viral infection to a single cell, and BV production was completely eliminated. AC141 was ubiquitinated by either vUbi or cellular Ubi, and this interaction was required for optimal BV production. Nucleocapsids in BV, but not ODV, were shown to be specifically ubiquitinated by vUbi, including a 100-kDa protein, as well as high-molecular-weight conjugates. The viral ubiquitinated 100-kDa BV-specific nucleocapsid protein was identified as AC66, which is known to be required for BV production and was shown by coimmunoprecipitation and mass spectrometry to interact with AC141. Confocal microscopy also showed that AC141, AC66, and vUbi interact at the nuclear periphery. These results suggest that ubiquitination of nucleocapsid proteins by vUbi functions as a signal to determine if a nucleocapsid will egress from the nucleus and form BV or remain in the nucleus to form ODV.IMPORTANCE Baculoviruses produce two types of virions called occlusion-derived virus (ODV) and budded virus (BV). ODVs are required for oral infection, whereas BV enables the systemic spread of virus to all host tissues, which is critical for killing insects. One of the important steps for BV production is the export of nucleocapsids out of the nucleus. This study investigated the molecular mechanisms that enable the selection of nucleocapsids for nuclear export instead of being retained within the nucleus, where they would become ODV. Our data show that ubiquitination, a universal cellular process, specifically tags nucleocapsids of BV, but not those found in ODV, using a virus-encoded ubiquitin (vUbi). Therefore, ubiquitination may be the molecular signal that determines if a nucleocapsid is destined to form a BV, thus ensuring lethal infection of the host.


Assuntos
Proteínas do Nucleocapsídeo/metabolismo , Nucleocapsídeo/metabolismo , Nucleopoliedrovírus/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Espectrometria de Massas , Nucleopoliedrovírus/genética , Células Sf9 , Spodoptera/virologia , Montagem de Vírus , Liberação de Vírus
9.
Oxid Med Cell Longev ; 2017: 5608287, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28642810

RESUMO

GlycA is a new composite measure of systemic inflammation and a predictor of many inflammatory diseases. GlycA is the nuclear magnetic resonance spectroscopy-derived signal arising from glucosamine residues on acute-phase proteins. This study aimed to evaluate how exercise-based lifestyle interventions modulate GlycA in persons at risk for type 2 diabetes. GlycA, fitness, and body habitus were measured in 169 sedentary adults (45-75 years) with prediabetes randomly assigned to one of four six-month exercise-based lifestyle interventions. Interventions included exercise prescription based on the amount (energy expenditure (kcal/kg weight/week (KKW)) and intensity (%VO2peak). The groups were (1) low-amount/moderate-intensity (10KKW/50%) exercise; (2) high-amount/moderate-intensity (16KKW/50%) exercise; (3) high-amount/vigorous-intensity (16KKW/75%) exercise; and (4) a Clinical Lifestyle (combined diet plus low-amount/moderate-intensity exercise) intervention. Six months of exercise training and/or diet-reduced GlycA (mean Δ: -6.8 ± 29.2 µmol/L; p = 0.006) and increased VO2peak (mean Δ: 1.98 ± 2.6 mL/kg/min; p < 0.001). Further, visceral (mean Δ: -21.1 ± 36.6 cm2) and subcutaneous fat (mean Δ: -24.3 ± 41.0 cm2) were reduced, while liver density (mean Δ: +2.3 ± 6.5HU) increased, all p < 0.001. When including individuals in all four interventions, GlycA reductions were associated with reductions in visceral adiposity (p < 0.03). Exercise-based lifestyle interventions reduced GlycA concentrations through mechanisms related to exercise-induced modulations of visceral adiposity. This trial is registered with Clinical Trial Registration Number NCT00962962.


Assuntos
Biomarcadores/metabolismo , Peso Corporal/fisiologia , Exercício Físico/fisiologia , Inflamação/diagnóstico , Estado Pré-Diabético/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
J Virol ; 91(5)2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28031365

RESUMO

Baculovirus occlusion-derived virus (ODV) initiates infection of lepidopteran larval hosts by binding to the midgut epithelia, which is mediated by per os infectivity factors (PIFs). Autographa californica multiple nucleopolyhedrovirus (AcMNPV) encodes seven PIF proteins, of which PIF1 to PIF4 form a core complex in ODV envelopes to which PIF0 and PIF6 loosely associate. Deletion of any pif gene results in ODV being unable to bind or enter midgut cells. AC83 also associates with the PIF complex, and this study further analyzed its role in oral infectivity to determine if it is a PIF protein. It had been proposed that AC83 possesses a chitin binding domain that enables transit through the peritrophic matrix; however, no chitin binding activity has ever been demonstrated. AC83 has been reported to be found only in the ODV envelopes, but in contrast, the Orgyia pseudotsugata MNPV AC83 homolog is associated with both ODV nucleocapsids and envelopes. In addition, unlike known pif genes, deletion of ac83 eliminates nucleocapsid formation. We propose a new model for AC83 function and show AC83 is associated with both ODV nucleocapsids and envelopes. We also further define the domain required for nucleocapsid assembly. The cysteine-rich region of AC83 is also shown not to be a chitin binding domain but a zinc finger domain required for the recruitment or assembly of the PIF complex to ODV envelopes. As such, AC83 has all the properties of a PIF protein and should be considered PIF8. In addition, pif7 (ac110) is reported as the 38th baculovirus core gene.IMPORTANCE ODV is essential for the per os infectivity of the baculovirus AcMNPV. To initiate infection, ODV binds to microvilli of lepidopteran midgut cells, a process which requires a group of seven virion envelope proteins called PIFs. In this study, we reexamined the function of AC83, a protein that copurifies with the ODV PIFs, to determine its role in the oral infection process. A zinc finger domain was identified and a new model for AC83 function was proposed. In contrast to previous studies, AC83 was found to be physically located in both the envelope and nucleocapsid of ODV. By deletion analysis, the AC83 domain required for nucleocapsid assembly was more finely delineated. We show that AC83 is required for PIF complex formation and conclude that it is a true per os infectivity factor and should be called PIF8.


Assuntos
Proteínas do Capsídeo/fisiologia , Nucleocapsídeo/metabolismo , Nucleopoliedrovírus/fisiologia , Sequência de Aminoácidos , Animais , Sequência Conservada , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Células Sf9 , Spodoptera , Montagem de Vírus , Replicação Viral
11.
J Invertebr Pathol ; 141: 24-33, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27793742

RESUMO

Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is the type species for the genus Alphabaculovirus in the family Baculoviridae. In nature, AcMNPV infection begins with ingestion of viral occlusion bodies (OBs) from which occlusion-derived viruses (ODV) are released to infect midgut cells. This study explored the early stages of Trichoplusia ni midgut infection using recombinant viruses expressing green fluorescent protein (GFP) and/or a VP39-mCherry fusion protein under the control of early and late promoters, respectively. Using a recombinant ie1:GFP virus, the anterior midgut region was identified as the predominant site for primary infection. Infection of midguts using the GFP-VP39mCherry-dual labelled recombinant virus revealed that active viral replication and cell-to-cell spread was required for the formation of infection foci and the subsequent spread to uninfected midgut cells and tracheoblasts. The spread of the infection from primary infected cells to secondary cells within the midgut was shown to be dependent upon the membrane fusion protein GP64.


Assuntos
Mariposas/virologia , Nucleopoliedrovírus/metabolismo , Viroses/veterinária , Animais , Western Blotting , Sistema Digestório/virologia , Proteínas Virais/metabolismo , Virulência
12.
Diabetologia ; 59(10): 2088-98, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27421729

RESUMO

AIMS/HYPOTHESIS: Although the Diabetes Prevention Program (DPP) established lifestyle changes (diet, exercise and weight loss) as the 'gold standard' preventive therapy for diabetes, the relative contribution of exercise alone to the overall utility of the combined diet and exercise effect of DPP is unknown; furthermore, the optimal intensity of exercise for preventing progression to diabetes remains very controversial. To establish clinical efficacy, we undertook a study (2009 to 2013) to determine: how much of the effect on measures of glucose homeostasis of a 6 month programme modelled after the first 6 months of the DPP is due to exercise alone; whether moderate- or vigorous-intensity exercise is better for improving glucose homeostasis; and to what extent amount of exercise is a contributor to improving glucose control. The primary outcome was improvement in fasting plasma glucose, with improvement in plasma glucose AUC response to an OGTT as the major secondary outcome. METHODS: The trial was a parallel clinical trial. Sedentary, non-smokers who were 45-75 year old adults (n = 237) with elevated fasting glucose (5.28-6.94 mmol/l) but without cardiovascular disease, uncontrolled hypertension, or diabetes, from the Durham area, were studied at Duke University. They were randomised into one of four 6 month interventions: (1) low amount (42 kJ kg body weight(-1) week(-1) [KKW])/moderate intensity: equivalent of expending 42 KKW (e.g. walking ∼16 km [8.6 miles] per week) with moderate-intensity (50% [Formula: see text]) exercise; (2) high amount (67 KKW)/moderate intensity: equivalent of expending 67 KKW (∼22.3 km [13.8 miles] per week) with moderate-intensity exercise; (3) high amount (67 KKW)/vigorous intensity: equivalent to group 2, but with vigorous-intensity exercise (75% [Formula: see text]); and (4) diet + 42 KKW moderate intensity: same as group 1 but with diet and weight loss (7%) to mimic the first 6 months of the DPP. Computer-generated randomisation lists were provided by our statistician (G. P. Samsa). The randomisation list was maintained by L. H. Willis and C. A. Slentz with no knowledge of or input into the scheduling, whereas all scheduling was done by L. A. Bateman, with no knowledge of the randomisation list. Subjects were automatically assigned to the next group listed on the randomisation sheet (with no ability to manipulate the list order) on the day that they came in for the OGTT, by L. H. Willis. All plasma analysis was done blinded by the individuals doing the measurements (i.e. lipids, glucose, insulin). Subjects and research staff (other than individuals analysing the blood) were not blinded to the group assignments. RESULTS: Number randomised, completers and number analysed with complete OGTT data for each group were: low-amount/moderate-intensity (61, 43, 35); high-amount/moderate-intensity (61, 44, 40); high-amount/vigorous-intensity (61, 43, 38); diet/exercise (54, 45, 37), respectively. Only the diet and exercise group experienced a decrease in fasting glucose (p < 0.001). The means and 95% CIs for changes in fasting glucose (mmol/l) for each group were: high-amount/moderate-intensity -0.07 (-0.20, 0.06); high-amount/vigorous 0.06 (-0.07, 0.19); low-amount/moderate 0.05 (-0.05, 0.15); and diet/exercise -0.32 (-0.46, -0.18). The effects sizes for each group (in the same order) were: 0.17, 0.15, 0.18 and 0.71, respecively. For glucose tolerance (glucose AUC of OGTT), similar improvements were observed for the diet and exercise (8.2% improvement, effect size 0.73) and the 67 KKW moderate-intensity exercise (6.4% improvement, effect size 0.60) groups; moderate-intensity exercise was significantly more effective than the same amount of vigorous-intensity exercise (p < 0.0207). The equivalent amount of vigorous-intensity exercise alone did not significantly improve glucose tolerance (1.2% improvement, effect size 0.21). Changes in insulin AUC, fasting plasma glucose and insulin did not differ among the exercise groups and were numerically inferior to the diet and exercise group. CONCLUSIONS/INTERPRETATION: In the present clinical efficacy trial we found that a high amount of moderate-intensity exercise alone was very effective at improving oral glucose tolerance despite a relatively modest 2 kg change in body fat mass. These data, combined with numerous published observations of the strong independent relation between postprandial glucose concentrations and prediction of future diabetes, suggest that walking ∼18.2 km (22.3 km prescribed with 81.6% adherence in the 67 KKW moderate-intensity group) per week may be nearly as effective as a more intensive multicomponent approach involving diet, exercise and weight loss for preventing the progression to diabetes in prediabetic individuals. These findings have important implications for the choice of clinical intervention to prevent progression to type 2 diabetes for those at high risk. TRIAL REGISTRATION: ClinicalTrials.gov NCT00962962 FUNDING: The study was funded by National Institutes for Health National Institute of Diabetes and Digestive and Kidney Diseases (NIH-NDDK) (R01DK081559).


Assuntos
Exercício Físico/fisiologia , Estado Pré-Diabético/dietoterapia , Estado Pré-Diabético/terapia , Idoso , Glicemia/metabolismo , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/terapia , Feminino , Teste de Tolerância a Glucose , Homeostase/fisiologia , Humanos , Insulina/metabolismo , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/metabolismo , Redução de Peso/fisiologia
13.
J Appl Physiol (1985) ; 118(12): 1474-82, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25882384

RESUMO

Most health organizations recommend a combination of aerobic training (AT) and resistance training (RT), yet few studies have compared their acute (within 24 h of the last exercise bout) and sustained (after 14 days of no exercise training) effects alone and in combination on glucose metabolism. The present study (Studies Targeting Risk Reduction Interventions through Defined Exercise-Aerobic Training and/or Resistance Training) compared the effects of AT, RT, and the combination (AT/RT) on insulin action at both acute and sustained phases. Subjects (N = 196) were 18-70 yr old (mean age = 50 yr), overweight (mean body mass index = 30 kg/m2), sedentary with moderate dyslipidemia, and were randomized into one of three 8-mo exercise groups: 1) RT: 3 days/wk, 8 exercises, 3 sets/exercise, 8-12 repetitions/set; 2) AT: equivalent to ∼19.2 km/wk (12 miles/wk) at 75% peak O2 consumption; 3) AT/RT: the combination of AT and RT. One hundred forty-four subjects completed the intervention. Eighty-eight subjects completed all pre- and postintervention testing visits. Insulin sensitivity, glucose effectiveness, and disposition index were measured via a frequently sampled intravenous glucose tolerance test with subsequent minimal model analyses. AT/RT resulted in greater improvements in insulin sensitivity, ß-cell function (disposition index), and glucose effectiveness than either AT or RT alone (all P < 0.05). Approximately 52% of the improvement in insulin sensitivity by AT/RT was retained 14 days after the last exercise training bout. Neither AT or RT led to acute or chronic improvement in sensitivity index. In summary, only AT/RT (which required twice as much time as either alone) led to significant acute and sustained benefits in insulin sensitivity


Assuntos
Exercício Físico/fisiologia , Resistência à Insulina/fisiologia , Insulina/metabolismo , Sobrepeso/metabolismo , Educação Física e Treinamento/métodos , Treinamento Resistido , Adolescente , Adulto , Idoso , Limiar Anaeróbio/fisiologia , Composição Corporal/fisiologia , Dislipidemias/sangue , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Humanos , Células Secretoras de Insulina/fisiologia , Masculino , Pessoa de Meia-Idade , Sobrepeso/reabilitação , Comportamento de Redução do Risco , Comportamento Sedentário , Adulto Jovem
14.
Virology ; 468-470: 160-171, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25173193

RESUMO

IE0 and IE1 of the baculovirus Autographa californica multiple nucleopolyhedrovirus are essential transregulatory proteins required for both viral DNA replication and transcriptional transactivation. IE0 is identical to IE1 except for 54 amino acids at the N-terminus but the functional differences between these two proteins remain unclear. The purpose of this study was to determine the separate roles of these critical proteins in the virus life cycle. Unlike prior studies, IE0 and IE1 were analyzed using viruses that expressed ie0 and ie1 from an identical promoter so that the timing and levels of expression were comparable. IE0 and IE1 were found to equally support viral DNA replication and budded virus (BV) production. However, specific viral promoters were selectively transactivated by IE0 relative to IE1 but only when expressed at low levels. These results indicate that IE0 preferentially transactivates specific viral genes at very early times post-infection enabling accelerated replication and BV production.


Assuntos
Baculoviridae/metabolismo , Regulação Viral da Expressão Gênica/fisiologia , Proteínas Imediatamente Precoces/metabolismo , Transativadores/metabolismo , Replicação Viral/fisiologia , Animais , Linhagem Celular , Proteínas Imediatamente Precoces/genética , Mariposas/citologia , Plasmídeos , Transativadores/genética , Transcrição Gênica , Ativação Transcricional
15.
J Appl Physiol (1985) ; 113(12): 1831-7, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23019316

RESUMO

Recent guidelines on exercise for weight loss and weight maintenance include resistance training as part of the exercise prescription. Yet few studies have compared the effects of similar amounts of aerobic and resistance training on body mass and fat mass in overweight adults. STRRIDE AT/RT, a randomized trial, compared aerobic training, resistance training, and a combination of the two to determine the optimal mode of exercise for obesity reduction. Participants were 119 sedentary, overweight or obese adults who were randomized to one of three 8-mo exercise protocols: 1) RT: resistance training, 2) AT: aerobic training, and 3) AT/RT: aerobic and resistance training (combination of AT and RT). Primary outcomes included total body mass, fat mass, and lean body mass. The AT and AT/RT groups reduced total body mass and fat mass more than RT (P < 0.05), but they were not different from each other. RT and AT/RT increased lean body mass more than AT (P < 0.05). While requiring double the time commitment, a program of combined AT and RT did not result in significantly more fat mass or body mass reductions over AT alone. Balancing time commitments against health benefits, it appears that AT is the optimal mode of exercise for reducing fat mass and body mass, while a program including RT is needed for increasing lean mass in middle-aged, overweight/obese individuals.


Assuntos
Tecido Adiposo/fisiopatologia , Peso Corporal , Exercício Físico , Sobrepeso/fisiopatologia , Aptidão Física , Treinamento Resistido/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/reabilitação , Resultado do Tratamento
16.
Virology ; 431(1-2): 29-39, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22682215

RESUMO

Autographa californica multiple nucleopolyhedrovirus (AcMNPV) ac146 is a highly conserved gene in the Alpha- and Betabaculovirus genera that has an unknown function. Northern blot analysis and transcript mapping showed that ac146 is transcribed at late times post infection as a 1.2 kb mRNA. To determine the role of ac146 in the baculovirus life cycle ac146 knock out viruses were constructed. Transfection and plaque assays showed that all the ac146 deletions produced a single cell phenotype indicating that no infectious budded virus (BV) was produced, however occlusion bodies were formed. The lack of BV production was confirmed by viral titration utilizing both qPCR and TCID50. Analysis of BV and occlusion derived virus (ODV) revealed that AC146 is associated with both forms of the virus and is modified specifically in ODV. This study therefore demonstrates that AC146 is a late virion associated protein and is essential for the viral life cycle.


Assuntos
Baculoviridae/fisiologia , Técnicas de Inativação de Genes , Proteínas Virais/metabolismo , Liberação de Vírus , Sequência de Aminoácidos , Animais , Baculoviridae/genética , Linhagem Celular , Dados de Sequência Molecular , Spodoptera , Transfecção , Carga Viral , Ensaio de Placa Viral , Proteínas Virais/genética
17.
Med Sci Sports Exerc ; 44(10): 2033-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22525775

RESUMO

PURPOSE: Our study characterizes food and energy intake responses to long-term aerobic training (AT) and resistance training (RT) during a controlled 8-month trial. METHODS: In the STRRIDE-AT/RT trial, overweight/obese sedentary dyslipidemic men and women were randomized to AT (n = 39), RT (n = 38), or a combined treatment (AT/RT, n = 40) without any advice to change their food intakes. Quantitative food intake assessments and food frequency questionnaires were collected at baseline (before training) and after 8 months of training (end of training); body mass (BM) and fat-free mass (FFM) were also assessed. RESULTS: In AT and AT/RT, respectively, meaningful decreases in reported energy intake (REI) (-217 and -202 kcal, P < 0.001) and in intakes of fat (-14.9 and -14.9 g, P < 0.001, P = 0.004), protein (-8.3 and -10.7 g, P = 0.002, P < 0.001), and carbohydrate (-28.1 and -14.7 g, P = 0.001, P = 0.030) were found by food frequency questionnaires. REI relative to FFM decreased (P < 0.001 and P = 0.002), as did intakes of fat (-0.2 and -0.3 g, P = 0.003 and P = 0.014) and protein (-0.1 and -0.2 g, P = 0.005 and P < 0.001) in AT and AT/RT and carbohydrate (-0.5 g, P < 0.003) in AT only. For RT, REI by quantitative daily dietary intake decreased (-3.0 kcal.kg(-1) FFM, P = 0.046), as did fat intake (-0.2 g, P = 0.033). BM decreased in AT (-1.3 kg, P = 0.006) and AT/RT (-1.5 kg, P = 0.001) but was unchanged (0.6 kg, P = 0.176) in RT. CONCLUSIONS: Previously sedentary subjects completing 8 months of AT or AT/RT reduced their intakes of calories and macronutrients and BM. In RT, fat intakes and REI (when expressed per FFM) decreased, BM was unchanged, and FFM increased.


Assuntos
Ingestão de Energia/fisiologia , Exercício Físico/fisiologia , Treinamento Resistido , Tecido Adiposo/anatomia & histologia , Tecido Adiposo/fisiologia , Adulto , Composição Corporal/fisiologia , Índice de Massa Corporal , Dislipidemias/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Sobrepeso/fisiopatologia , Comportamento Sedentário , Inquéritos e Questionários
18.
Am J Physiol Endocrinol Metab ; 301(5): E1033-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21846904

RESUMO

While the benefits of exercise are clear, many unresolved issues surround the optimal exercise prescription. Many organizations recommend aerobic training (AT) and resistance training (RT), yet few studies have compared their effects alone or in combination. The purpose of this study, part of Studies Targeting Risk Reduction Interventions Through Defined Exercise-Aerobic Training and/or Resistance Training (STRRIDE/AT/RT), was to compare the effects of AT, RT, and the full combination (AT/RT) on central ectopic fat, liver enzymes, and fasting insulin resistance [homeostatic model assessment (HOMA)]. In a randomized trial, 249 subjects [18-70 yr old, overweight, sedentary, with moderate dyslipidemia (LDL cholesterol 130-190 mg/dl or HDL cholesterol ≤ 40 mg/dl for men or ≤ 45 mg/dl for women)] performed an initial 4-mo run-in period. Of these, 196 finished the run-in and were randomized into one of the following 8-mo exercise-training groups: 1) RT, which comprised 3 days/wk, 8 exercises, 3 sets/exercise, 8-12 repetitions/set, 2) AT, which was equivalent to ∼19.2 km/wk (12 miles/wk) at 75% peak O(2) uptake, and 3) full AT + full RT (AT/RT), with 155 subjects completing the intervention. The primary outcome variables were as follows: visceral and liver fat via CT, plasma liver enzymes, and HOMA. AT led to significant reductions in liver fat, visceral fat, alanine aminotransferase, HOMA, and total and subcutaneous abdominal fat (all P < 0.05). RT resulted in a decrease in subcutaneous abdominal fat (P < 0.05) but did not significantly improve the other variables. AT was more effective than RT at improving visceral fat, liver-to-spleen ratio, and total abdominal fat (all P < 0.05) and trended toward a greater reduction in liver fat score (P < 0.10). The effects of AT/RT were statistically indistinguishable from the effects of AT. These data show that, for overweight and obese individuals who want to reduce measures of visceral fat and fatty liver infiltration and improve HOMA and alanine aminotransferase, a moderate amount of aerobic exercise is the most time-efficient and effective exercise mode.


Assuntos
Exercício Físico/fisiologia , Resistência à Insulina , Gordura Intra-Abdominal/metabolismo , Fígado/enzimologia , Fígado/metabolismo , Sobrepeso/terapia , Treinamento Resistido , Adolescente , Adulto , Idoso , Técnicas de Diagnóstico Endócrino , Terapia por Exercício/métodos , Feminino , Homeostase/fisiologia , Humanos , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/fisiologia , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Sobrepeso/diagnóstico , Sobrepeso/enzimologia , Sobrepeso/metabolismo , Comportamento de Redução do Risco , Adulto Jovem
19.
Am J Cardiol ; 108(6): 838-44, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21741606

RESUMO

Aerobic training (AT) improves the metabolic syndrome (MS) and its component risk factors; however, to our knowledge, no randomized clinical studies have addressed whether resistance training (RT) improves the MS when performed alone or combined with AT. Sedentary, overweight dyslipidemic men and women, aged 18 to 70 years completed a 4-month inactive run-in period and were randomized to 1 of 3 eight-month exercise programs (n = 196). The exercise programs were (1) RT (3 days/week, 3 sets/day of 8 to 12 repetitions of 8 different exercises targeting all major muscle groups); (2) AT (∼120 minutes/week at 75% of the maximum oxygen uptake), and (3) AT and RT combined (AT/RT) (exact combination of AT and RT). Of the 196 randomized patients, 144 completed 1 of the 3 exercise programs. The 86 participants with complete data for all 5 MS criteria were used in the present analysis, and a continuous MS z score was calculated. Eight months of RT did not change the MS score. AT improved the MS score (p <0.07) and showed a trend toward significance compared to RT (p <0.10). AT/RT significantly decreased the MS score and was significantly different from RT alone. In conclusion, RT was not effective at improving the MS score; however, AT was effective. Combined AT and RT was similarly effective but not different from AT alone. When weighing the time commitment versus health benefit, the data suggest that AT alone was the most efficient mode of exercise for improving cardiometabolic health.


Assuntos
Terapia por Exercício/métodos , Síndrome Metabólica/terapia , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , North Carolina , Consumo de Oxigênio/fisiologia , Cooperação do Paciente , Treinamento Resistido/métodos , Fatores de Risco , Comportamento de Redução do Risco , Comportamento Sedentário , Resultado do Tratamento
20.
Med Sci Sports Exerc ; 43(9): 1744-51, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21364488

RESUMO

PURPOSE: An active lifestyle is widely recognized as having a beneficial effect on cardiovascular health. However, no clear consensus exists as to whether exercise training increases overall physical activity energy expenditure (PAEE) or whether individuals participating in regular exercise compensate by reducing their off-exercise physical activity. The purpose of this study was to evaluate changes in PAEE in response to aerobic training (AT), resistance training (RT), or combined aerobic and resistance training (AT/RT). METHODS: Data are from 82 participants in the Studies of Targeted Risk Reduction Interventions through Defined Exercise-Aerobic Training versus Resistance Training study, a randomized trial of overweight (body mass index = 25-35 kg·m(-2)) adults, in which participants were randomized to receive 8 months of AT, RT, or AT/RT. All subjects completed a 4-month control period before randomization. PAEE was measured using triaxial RT3 accelerometers, which subjects wore for a 5- to 7-d period before and after the exercise intervention. Data reduction was performed with a previously published computer-based algorithm. RESULTS: There was no significant change in off-exercise PAEE in any of the exercise training groups. We observed a significant increase in total PAEE that included the exercise training, in both AT and AT/RT but not in RT. CONCLUSIONS: Eight months of exercise training was not associated with a compensatory reduction in off-exercise physical activity, regardless of exercise modality. The absence of compensation is particularly notable for AT/RT subjects, who performed a larger volume of exercise than did AT or RT subjects. We believe that the extended duration of our exercise training program was the key factor in allowing subjects to reach a new steady-state level of physical activity within their daily lives.


Assuntos
Metabolismo Energético , Exercício Físico/fisiologia , Atividade Motora/fisiologia , Sobrepeso/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Treinamento Resistido
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