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1.
Physiol Rep ; 6(14): e13789, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30009570

RESUMO

Curcumin, a naturally occurring plant polyphenolic compound, may have beneficial effects in nonalcoholic steatohepatitis (NASH) development. We examined whether curcumin supplementation could be used in both prevention and treatment of NASH with fibrosis. Female Wistar rats were provided ad libitum access to a "western diet" (WD) high in fat (43% kcal), sucrose (29% kcal), and cholesterol (2% w/v), as well as 15% fructose drinking water. Intraperitoneal CC14 injections (0.5 mL/kg) were also administered at weeks 1, 2, 4, and 6 to accelerate development of a NASH with fibrosis phenotype. Rats were randomized to four groups (n = 9-12/group) and fed ad libitum: (1) WD for 8-weeks (8WD), (2) WD enriched with curcumin for 8-weeks (8WD+C; 0.2% curcumin, BCM-95, DolCas Biotech) to assess prevention, (3) WD for 12-weeks (12WD), (4) WD for 8-weeks followed by 4-weeks WD+C (12WD+C) to assess treatment. Curcumin prevention (8WD vs. 8WD+C) attenuated (P < 0.05) histological liver inflammation, molecular markers of fibrosis (Col1a1 mRNA) and a serum marker of liver injury (AST). Curcumin treatment (12WD vs. 12WD+C) reduced (P < 0.05) hepatocellular inflammation, steatosis, NAFLD Activity Scores, and serum markers of liver injury (AST, ALP). Moreover, curcumin treatment also increased hepatic pACC/ACC, ApoB100, and SOD1 protein, and decreased hepatic FGF-21 levels; whereas, curcumin prevention increased hepatic glutathione levels. Both curcumin prevention and treatment reduced molecular markers of hepatic fibrosis (Col1a1 mRNA) and inflammation (TNF-α, SPP1 mRNA). Curcumin supplementation beneficially altered the NASH phenotype in female Wistar rats, particularly the reversal of hepatocellular inflammation.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Curcumina/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Anti-Inflamatórios/administração & dosagem , Apolipoproteína B-100/metabolismo , Colágeno/metabolismo , Curcumina/administração & dosagem , Dieta Hiperlipídica/efeitos adversos , Feminino , Glutationa/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Osteopontina/metabolismo , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
2.
Physiol Rep ; 6(5)2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29527830

RESUMO

Previous investigations have reported a relationship between skeletal muscle phenotype and motor unit (MU) firing parameters during submaximal contractions. The purpose of the current investigation, however, was to examine the relationships between motor unit firing behavior during a maximal voluntary contraction, Myosin Heavy Chain (MHC) isoform content, and various molecular neuromuscular targets of the vastus lateralis (VL) muscle in resistance-trained men. Ten resistance-trained males completed a trapezoidal ramp contraction up to 100% of their maximal voluntary isometric strength (MVIC). Surface electromyography was recorded from the VL using a multichannel electrode array and decomposed to examine the firing characteristics of individual MUs. A skeletal muscle biopsy of the VL was also collected from each subject. Regression analyses were performed to identify relationships between type II fiber area and the slopes and/or intercepts of the mean firing rate (FRMEAN ) versus recruitment threshold (RT), max firing rate (FRMAX ) versus RT, and RT versus MU action potential amplitude (MUAPPP ) relationships. There were significant inverse relationships between type II fiber area and the y-intercept of the FR versus RT relationship (P < 0.05). Additionally, strong relationships (r > 0.5) were found between type II fiber area and FRMEAN versus RT slope and RT versus MUAPPP slope and intercept. These data further support the hypothesis that skeletal muscle phenotype is related to MU behavior during isometric contraction. However, our data, in concert with previous investigations, may suggest that these relationships are influenced by the intensity of the contraction.


Assuntos
Contração Isométrica , Músculo Esquelético/fisiologia , Recrutamento Neurofisiológico , Potencial Evocado Motor , Humanos , Masculino , Músculo Esquelético/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Fenótipo , Adulto Jovem
3.
Eur J Appl Physiol ; 117(12): 2587-2600, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29075862

RESUMO

PURPOSE: To compare the effects of external pneumatic compression (EPC) and sham when used concurrently with high intensity interval training (HIIT) on performance-related outcomes and recovery-related molecular measures. METHODS: Eighteen recreationally endurance-trained male participants (age: 21.6 ± 2.4 years, BMI: 25.7 ± 0.5 kg/m2, VO2peak: 51.3 ± 0.9 mL/kg/min) were randomized to balanced sham and EPC treatment groups. Three consecutive days of HIIT followed by EPC/sham treatment (Days 2-4) and 3 consecutive days of recovery (Days 5-7) with EPC/sham only on Days 5-6 were employed. Venipuncture, flexibility and pressure-to-pain threshold (PPT) measurements were made throughout. Vastus lateralis muscle was biopsied at PRE (i.e., Day 1), 1-h post-EPC/sham treatment on Day 2 (POST1), and 24-h post-EPC/sham treatment on Day 7 (POST2). 6-km run time trial performance was tested at PRE and POST2. RESULTS: No group × time interaction was observed for flexibility, PPT, or serum measures of creatine kinase (CK), hsCRP, and 8-isoprostane. However, there was a main effect of time for serum CK (p = 0.005). Change from PRE in 6-km run times at POST2 were not significantly different between groups. Significant between-groups differences existed for change from PRE in atrogin-1 mRNA (p = 0.018) at the POST1 time point (EPC: - 19.7 ± 8.1%, sham: + 7.7 ± 5.9%) and atrogin-1 protein concentration (p = 0.013) at the POST2 time point (EPC: - 31.8 ± 7.5%, sham: + 96.0 ± 34.7%). In addition, change from PRE in poly-Ub proteins was significantly different between groups at both the POST1 (EPC: - 26.0 ± 10.3%, sham: + 34.8 ± 28.5%; p = 0.046) and POST2 (EPC: - 33.7 ± 17.2%, sham: + 21.4 ± 14.9%; p = 0.037) time points. CONCLUSIONS: EPC when used concurrently with HIIT and in subsequent recovery days reduces skeletal muscle markers of proteolysis.


Assuntos
Treinamento Intervalado de Alta Intensidade/métodos , Dispositivos de Compressão Pneumática Intermitente/efeitos adversos , Proteólise , Adulto , Proteína C-Reativa/metabolismo , Creatina Quinase/sangue , Dinoprosta/análogos & derivados , Dinoprosta/sangue , Treinamento Intervalado de Alta Intensidade/efeitos adversos , Humanos , Masculino , Proteínas Musculares/metabolismo , Músculo Quadríceps/irrigação sanguínea , Músculo Quadríceps/metabolismo , Músculo Quadríceps/fisiologia , Proteínas Ligases SKP Culina F-Box/metabolismo , Ubiquitinação
4.
Nutrients ; 9(9)2017 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-28869573

RESUMO

We sought to determine the effects of L-leucine (LEU) or different protein supplements standardized to LEU (~3.0 g/serving) on changes in body composition, strength, and histological attributes in skeletal muscle and adipose tissue. Seventy-five untrained, college-aged males (mean ± standard error of the mean (SE); age = 21 ± 1 years, body mass = 79.2 ± 0.3 kg) were randomly assigned to an isocaloric, lipid-, and organoleptically-matched maltodextrin placebo (PLA, n = 15), LEU (n = 14), whey protein concentrate (WPC, n = 17), whey protein hydrolysate (WPH, n = 14), or soy protein concentrate (SPC, n = 15) group. Participants performed whole-body resistance training three days per week for 12 weeks while consuming supplements twice daily. Skeletal muscle and subcutaneous (SQ) fat biopsies were obtained at baseline (T1) and ~72 h following the last day of training (T39). Tissue samples were analyzed for changes in type I and II fiber cross sectional area (CSA), non-fiber specific satellite cell count, and SQ adipocyte CSA. On average, all supplement groups including PLA exhibited similar training volumes and experienced statistically similar increases in total body skeletal muscle mass determined by dual X-ray absorptiometry (+2.2 kg; time p = 0.024) and type I and II fiber CSA increases (+394 µm² and +927 µm²; time p < 0.001 and 0.024, respectively). Notably, all groups reported increasing Calorie intakes ~600-800 kcal/day from T1 to T39 (time p < 0.001), and all groups consumed at least 1.1 g/kg/day of protein at T1 and 1.3 g/kg/day at T39. There was a training, but no supplementation, effect regarding the reduction in SQ adipocyte CSA (-210 µm²; time p = 0.001). Interestingly, satellite cell counts within the WPC (p < 0.05) and WPH (p < 0.05) groups were greater at T39 relative to T1. In summary, LEU or protein supplementation (standardized to LEU content) does not provide added benefit in increasing whole-body skeletal muscle mass or strength above PLA following 3 months of training in previously untrained college-aged males that increase Calorie intakes with resistance training and consume above the recommended daily intake of protein throughout training. However, whey protein supplementation increases skeletal muscle satellite cell number in this population, and this phenomena may promote more favorable training adaptations over more prolonged periods.


Assuntos
Adiposidade , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais , Leucina/administração & dosagem , Força Muscular , Hidrolisados de Proteína/administração & dosagem , Músculo Quadríceps/fisiologia , Treinamento Resistido , Proteínas de Soja/administração & dosagem , Gordura Subcutânea/fisiologia , Proteínas do Soro do Leite/administração & dosagem , Absorciometria de Fóton , Alabama , Biópsia , Proteínas Alimentares/efeitos adversos , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Ingestão de Energia , Humanos , Leucina/efeitos adversos , Masculino , Hidrolisados de Proteína/efeitos adversos , Músculo Quadríceps/citologia , Músculo Quadríceps/diagnóstico por imagem , Proteínas de Soja/efeitos adversos , Gordura Subcutânea/citologia , Gordura Subcutânea/diagnóstico por imagem , Fatores de Tempo , Resultado do Tratamento , Ultrassonografia , Proteínas do Soro do Leite/efeitos adversos , Adulto Jovem
5.
Physiol Rep ; 4(22)2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27884954

RESUMO

Next-generation RNA sequencing was employed to determine the acute and subchronic impact of peristaltic pulse external pneumatic compression (PEPC) of different target inflation pressures on global gene expression in human vastus lateralis skeletal muscle biopsy samples. Eighteen (N = 18) male participants were randomly assigned to one of the three groups: (1) sham (n = 6), 2) EPC at 30-40 mmHg (LP-EPC; n = 6), and 3) EPC at 70-80 mmHg (MP-EPC; n = 6). One hour treatment with sham/EPC occurred for seven consecutive days. Vastus lateralis skeletal muscle biopsies were performed at baseline (before first treatment; PRE), 1 h following the first treatment (POST1), and 24 h following the last (7th) treatment (POST2). Changes from PRE in gene expression were analyzed via paired comparisons within each group. Genes were filtered to include only those that had an RPKM ≥ 1.0, a fold-change of ≥1.5 and a paired t-test value of <0.01. For the sham condition, two genes at POST1 and one gene at POST2 were significantly altered. For the LP-EPC condition, nine genes were up-regulated and 0 genes were down-regulated at POST1 while 39 genes were up-regulated and one gene down-regulated at POST2. For the MP-EPC condition, two genes were significantly up-regulated and 21 genes were down-regulated at POST1 and 0 genes were altered at POST2. Both LP-EPC and MP-EPC acutely alter skeletal muscle gene expression, though only LP-EPC appeared to affect gene expression with subchronic application. Moreover, the transcriptome response to EPC demonstrated marked heterogeneity (i.e., genes and directionality) with different target inflation pressures.


Assuntos
Dispositivos de Compressão Pneumática Intermitente/efeitos adversos , Músculo Esquelético/metabolismo , Pressão , RNA/genética , Transcriptoma/genética , Adulto , Biópsia/métodos , Citrato (si)-Sintase/metabolismo , Humanos , Masculino , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/patologia , Oxirredução , Peristaltismo/fisiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ativação Transcricional , Regulação para Cima/genética , Adulto Jovem
6.
Exp Physiol ; 100(7): 852-64, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25982469

RESUMO

NEW FINDINGS: What is the central question of this study? Does 60 min of peristaltic pulse external pneumatic compression (EPC) alter gene and protein expression patterns related to metabolism, vascular biology, redox balance and inflammation in vastus lateralis biopsy samples? What is the main finding and its importance? A single bout of EPC transiently upregulates PGC-1α mRNA, while also upregulating endothelial nitric oxide synthase protein and nitric oxide metabolite concentrations in vastus lateralis biopsy samples. We investigated whether a single 60 min bout of whole-leg, lower pressure external pneumatic compression (EPC) altered select vascular, metabolic, antioxidant and inflammation-related mRNAs. Ten participants (eight male, two female; aged 22.0 ± 0.4 years) reported to the laboratory 4 h postprandial, and vastus lateralis muscle biopsies were obtained before (PRE) and 1 and 4 h after EPC treatment. Messenger RNA expression was analysed using real-time RT-PCR, and significant mRNA findings were investigated further by Western blot analysis of respective protein concentrations. Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) mRNA increased by 77% 1 h following EPC compared with PRE levels (P = 0.005), but no change in protein concentration 1 or 4 h post-EPC was observed. Increases in endothelial nitric oxide sythase (eNOS) mRNA (+44%) and superoxide dismutase 2 (SOD2) mRNA (+57%) 1 h post-EPC as well as an increase in interleukin-10 mRNA (+132%) 4 h post-EPC compared with PRE levels were observed, but only approached significance (P = 0.076, 0.077 and 0.074, respectively). Interestingly, eNOS protein (+40%, P = 0.025) and nitrate and nitrite (NOx) concentrations (+69%, P = 0.025) increased 1-4 h post-EPC. Moreover, SOD2 protein tended to increase from PRE to 4 h post-EPC (+43%, P = 0.074), although no changes in tissue 4-hydroxnonenal levels was observed. An acute bout of EPC transiently upregulates PGC-1α mRNA, while also upregulating eNOS protein and NOx concentrations in vastus lateralis biopsy samples. Future research should characterize the origin of these responses (e.g. vascular or muscle fibre cells) and how the acute effects of EPC application on gene and protein expression observed herein are associated with functional improvements (e.g. metabolism, vascular function) in acute and chronic models.


Assuntos
Perna (Membro)/fisiologia , Músculo Esquelético/metabolismo , Óxido Nítrico Sintase Tipo III/genética , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Feminino , Humanos , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Fatores de Transcrição/metabolismo , Ativação Transcricional/fisiologia , Regulação para Cima , Adulto Jovem
7.
Exp Physiol ; 98(1): 337-47, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22709650

RESUMO

Early vascular changes at the molecular level caused by adoption of a sedentary lifestyle are incompletely characterized. Herein, we employed the rodent wheel-lock model to identify mRNAs in the arterial wall that are responsive to the acute transition from higher to lower levels of daily physical activity. Specifically, we evaluated whether short-term cessation of voluntary wheel running alters vascular mRNA levels in rat conduit arteries previously reported to have marked increases (i.e. iliac artery) versus marked decreases (i.e. renal artery) in blood flow during running. We used young female Wistar rats with free access to voluntary running wheels. Following 23 days of voluntary running (average distance of ∼15 km per night; ∼4.4 h per night), rats in one group were rapidly transitioned to a sedentary state by locking the wheels for 7 days (n = 9; wheel-lock 7 day rats) or remained active in a second group for an additional 7 days (n = 9; wheel-lock 0 day rats). Real-time PCR was conducted on total RNA isolated from iliac and renal arteries to evaluate expression of 25 pro-atherogenic and anti-atherogenic genes. Compared with the iliac arteries of wheel-lock 0 day rats, iliac arteries of wheel-lock 7 day rats exhibited increased expression of TNFR1 (+19%), ET1 (+59%) and LOX-1 (+31%; all P < 0.05). Moreover, compared with renal arteries of wheel-lock 0 day rats, renal arteries of wheel-lock 7 day rats exhibited decreased expression of ETb (-23%), p47phox (-32%) and p67phox (-19%; all P < 0.05). These data demonstrate that cessation of voluntary wheel running for 7 days produces modest, but differential changes in mRNA levels between the iliac and renal arteries of healthy rats. This heterogeneous influence of short-term physical inactivity could be attributed to the distinct alteration in haemodynamic forces between arteries.


Assuntos
Artérias/metabolismo , Endotelina-1/genética , Atividade Motora/fisiologia , NADPH Oxidases/genética , Receptor de Endotelina B/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Artéria Renal/metabolismo , Corrida/fisiologia , Receptores Depuradores Classe E/genética , Animais , Feminino , Ílio/irrigação sanguínea , Fosfoproteínas/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
8.
Appl Physiol Nutr Metab ; 37(6): 1251-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23057577

RESUMO

Elevated markers of systemic inflammation are associated with impaired glucose tolerance and type 2 diabetes mellitus. Enhanced external counterpulsation (EECP) has been shown to decrease circulating concentrations of pro-inflammatory markers in coronary artery disease patients. Here we provide novel evidence that EECP intervention also has a beneficial effect on circulating markers of systemic inflammation coincident with improvements in glycemic control in subjects with abnormal glucose tolerance.


Assuntos
Contrapulsação , Intolerância à Glucose/terapia , Inflamação/terapia , Idoso , Biomarcadores/sangue , Proteína C-Reativa/análise , Intolerância à Glucose/sangue , Humanos , Inflamação/sangue , Resistência à Insulina , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/sangue
9.
Exp Biol Med (Maywood) ; 235(10): 1263-8, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20719817

RESUMO

The main objectives of this study were to examine the acute effect of a single dose of smokeless tobacco (ST) on central aortic blood pressure and wave reflection characteristics. Fifteen apparently healthy male subjects (aged 30.6 ± 6.2 y) were given a 2.5 g oral dose of ST after baseline measurements were recorded. Pulse wave analysis using radial artery applanation tonometry was performed in triplicate at baseline (0 min) and at 10-min intervals during (10, 20 and 30 min) and after (40, 50 and 60 min) ST use. An acute dose of ST was associated with a significant increase in heart rate (HR), central aortic systolic and diastolic blood pressure, peripheral brachial systolic and diastolic blood pressure, and aortic augmentation index normalized to a fixed heart rate of 75 bpm (AIx@75). Furthermore, ejection duration and round trip travel time of the reflected pressure wave (Δt(p)) were significantly decreased as a result of one time ST use. As a result of changes in aortic pressure wave reflection characteristics, there was a significant increase in wasted left ventricular pressure energy (LVE(w)) and the tension-time index (TTI) as a result of ST use. In conclusion, one time use of ST elicits significant transient increases in HR, central aortic pressures, AIx@75, the TTI and LVE(w). Chronic users subjected to decades of elevated central pressures and left ventricular work may have an increased cardiovascular risk as central aortic pressures are even more strongly related to cardiovascular outcomes than peripheral blood pressures.


Assuntos
Aorta/fisiologia , Pressão Sanguínea/fisiologia , Tabaco sem Fumaça/toxicidade , Adulto , Artéria Braquial/fisiologia , Diástole , Frequência Cardíaca , Hemodinâmica , Humanos , Masculino , Fatores de Risco , Sístole , Função Ventricular Esquerda , Adulto Jovem
10.
Innovations (Phila) ; 1(3): 99-104, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-22436642

RESUMO

BACKGROUND: : Patient demand for less invasive surgery and interest in avoiding sternotomy has led to the increased use of the minithoracotomy for mitral valve surgery. Although the feasibility of this approach has been established, few data are available regarding intermediate-term results. METHODS: : A total of 505 consecutive minithoracotomy mitral valve procedures performed between 1996 and 2004 were analyzed. Procedures were mitral replacement (191/505, 38%) and repair (314/505, 62%). Concomitant cardiac procedures were performed in 78 cases (13%) (maze 36, tricuspid 29, atrial septal defect/patent foramen ovale 13) and reoperation in 92 cases (18%). Arterial cannulation was ascending aorta in 403 cases (80%), femoral in 101 cases (20%), and axillary in 1 case (<1%). An endoluminal aortic clamp was used in 406 cases (80%), an external clamp was used in 19 cases (4%), and 80 procedures (16%) were performed with ventricular fibrillation. Robotic assistance was used in 12 cases (2%). RESULTS: : Mean patient age was 58.7 years (range 18-90 years). Median follow-up was 3.1 years. Operative mortality was 4 of 505 cases (<1%). Major complications included stroke in 7 cases (1%) and reoperation for bleeding in 18 cases (4%); there were no cases of mediastinitis. Late complications included chronic aortic dissection in 1 case (<1%) and mitral reoperation in 13 cases (3%) (subacute bacterial endocarditis 6, failed repair 2, other 5). Five-year survival was (83% ± 2%) and freedom from mitral reoperation was (96% ± 1%). Follow-up echocardiograms were available in 246 of 314 cases (78%) mitral repairs and mean mitral regurgitation grade was 1 ± 1. Mitral regurgitation was grade 3-4+ in 14 of 246 cases (6%) (subacute bacterial endocarditis 4, low ejection fraction 5, other 5). Five-year freedom from 3-4+ mitral regurgitation was 89% ± 3%. CONCLUSIONS: : Mitral valve surgery via minithoracotomy can be performed safely with a low perioperative complication rate. A durable technical result and excellent long-term survival can be expected.

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