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1.
Amino Acids ; 48(3): 779-789, 2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-26553453

RESUMO

We examined if supplementing trained cyclists (32 ± 2 year, 77.8 ± 2.6 kg, and 7.4 ± 1.2 year training) with 12 g/day (6 g/day L-Leucine, 2 g/day L-Isoleucine and 4 g/day L-Valine) of either branched-chain amino acids (BCAAs, n = 9) or a maltodextrin placebo (PLA, n = 9) over a 10-week training season affected select body composition, performance, and/or immune variables. Before and after the 10-week study, the following was assessed: (1) 4-h fasting blood draws; (2) dual X-ray absorptiometry body composition; (3) Wingate peak power tests; and (4) 4 km time-trials. No group × time interactions existed for total lean mass (P = 0.27) or dual-leg lean mass (P = 0.96). A significant interaction existed for body mass-normalized relative peak power (19 % increase in the BCAA group pre- to post-study, P = 0.01), and relative mean power (4 % increase in the BCAA group pre- to post-study, P = 0.01). 4 km time-trial time to completion approached a significant interaction (P = 0.08), as the BCAA group improved in this measure by 11 % pre- to post-study, though this was not significant (P = 0.15). There was a tendency for the BCAA group to present a greater post-study serum BCAA: L-Tryptophan ratio compared to the PLA group (P = 0.08). A significant interaction for neutrophil number existed (P = 0.04), as there was a significant 18 % increase within the PLA group from the pre- to post-study time point (P = 0.01). Chronic BCAA supplementation improves sprint performance variables in endurance cyclists. Additionally, given that BCAA supplementation blunted the neutrophil response to intense cycling training, BCAAs may benefit immune function during a prolonged cycling season.


Assuntos
Aminoácidos de Cadeia Ramificada/metabolismo , Atletas , Suplementos Nutricionais/análise , Neutrófilos/imunologia , Resistência Física , Adulto , Composição Corporal , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Adulto Jovem
2.
Nutr Metab (Lond) ; 11: 19, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24822076

RESUMO

BACKGROUND: We examined if a purported anti-inflammatory supplement (AF) abrogated Western-diet (WD)-induced liver pathology in rats. AF contained: 1) protein concentrates from bovine colostrum and avian egg yolk; 2) herbal adaptogens and antioxidants; and 3) acetyl-L-carnitine. METHODS: Nine month-old male Brown Norway rats were allowed ad libitum access to WD for 41-43 days and randomly assigned to WD + AF feeding twice daily for the last 31-33 days (n = 8), or WD and water-placebo feeding twice daily for the last 31-33 days (n = 8). Rats fed a low-fat/low-sucrose diet (CTL, n = 6) for 41-43 days and administered a water-placebo twice daily for the last 31-33 days were also studied. Twenty-four hours following the last gavage-feed, liver samples were analyzed for: a) select mRNAs (via RT-PCR) as well as genome-wide mRNA expression patterns (via RNA-seq); b) lipid deposition; and, c) protein carbonyl and total antioxidant capacity (TAC). Serum was also examined for TAC, 8-isoprostane and clinical chemistry markers. RESULTS: WD + AF rats experienced a reduction in liver Tnf-α mRNA (-2.8-fold, p < 0.01). Serum and liver TAC was lower in WD + AF versus WD and CTL rats (p < 0.05), likely due to exogenous antioxidant ingredients provided through AF as evidenced by a tendency for mitochondrial SOD2 mRNA to increase in WD + AF versus CTL rats (p = 0.07). Liver fat deposition nor liver protein carbonyl content differed between WD + AF versus WD rats, although liver protein carbonyls tended to be lower in WD + AF versus CTL rats (p = 0.08). RNA-seq revealed that 19 liver mRNAs differed between WD + AF versus WD when both groups were compared with CTL rats (+/- 1.5-fold, p < 0.01). Bioinformatics suggest that AF prevented WD-induced alterations in select genes related to the transport and metabolism of carbohydrates in favor of select genes related to lipid transport and metabolism. Finally, serum clinical safety markers and liver pathology (via lesion counting) suggests that chronic consumption of AF was well tolerated. CONCLUSIONS: AF supplementation elicits select metabolic, anti-inflammatory, and anti-oxidant properties which was in spite of WD feeding and persisted up to 24 hours after receiving a final dose.

3.
Am J Physiol Regul Integr Comp Physiol ; 304(11): R1024-35, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23552494

RESUMO

The purpose of the present study was to partially phenotype male and female rats from generations 8-10 (G8-G10) that had been selectively bred to possess low (LVR) vs. high voluntary running (HVR) behavior. Over the first 6 days with wheels, 34-day-old G8 male and female LVRs ran shorter distances (P < 0.001), spent less time running (P < 0.001), and ran slower (P < 0.001) than their G8 male and female HVR counterparts, respectively. HVR and LVR lines consumed similar amounts of standard chow with or without wheels. No inherent difference existed in PGC-1α mRNA in the plantaris and soleus muscles of LVR and HVR nonrunners, although G8 LVR rats inherently possessed less NADH-positive superficial plantaris fibers compared with G8 HVR rats. While day 28 body mass tended to be greater in both sexes of G9-G10 LVR nonrunners vs. G9-G10 HVR nonrunners (P = 0.06), body fat percentage was similar between lines. G9-G10 HVRs had fat mass loss after 6 days of running compared with their prerunning values, while LVR did not lose or gain fat mass during the 6-day voluntary running period. RNA deep sequencing efforts in the nucleus accumbens showed only eight transcripts to be >1.5-fold differentially expressed between lines in HVR and LVR nonrunners. Interestingly, HVRs presented less Oprd1 mRNA, which ties in to potential differences in dopaminergic signaling between lines. This unique animal model provides further evidence as to how exercise may be mechanistically regulated.


Assuntos
Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Corrida/fisiologia , Absorciometria de Fóton , Animais , Composição Corporal/genética , Composição Corporal/fisiologia , DNA Complementar/biossíntese , DNA Complementar/genética , Ingestão de Alimentos/genética , Ingestão de Alimentos/fisiologia , Feminino , Membro Posterior/fisiologia , Masculino , Fibras Musculares Esqueléticas/fisiologia , NAD/metabolismo , Núcleo Accumbens/metabolismo , Tamanho do Órgão/fisiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Fenótipo , Condicionamento Físico Animal , RNA Mensageiro/biossíntese , Proteínas de Ligação a RNA/biossíntese , Proteínas de Ligação a RNA/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Corrida/psicologia , Caracteres Sexuais , Fatores de Transcrição/biossíntese , Fatores de Transcrição/metabolismo
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