15 research outputs found
Functional crosstalk of PGC-1 coactivators and inflammation in skeletal muscle pathophysiology
Skeletal muscle is an organ involved in whole body movement and energy metabolism with the ability to dynamically adapt to different states of (dis-)use. At a molecular level, the peroxisome proliferator-activated receptor Îł coactivators 1 (PGC-1s) are important mediators of oxidative metabolism in skeletal muscle and in other organs. Musculoskeletal disorders as well as obesity and its sequelae are associated with PGC-1 dysregulation in muscle with a concomitant local or systemic inflammatory reaction. In this review, we outline the function of PGC-1 coactivators in physiological and pathological conditions as well as the complex interplay of metabolic dysregulation and inflammation in obesity with special focus on skeletal muscle. We further put forward the hypothesis that, in this tissue, oxidative metabolism and inflammatory processes mutually antagonize each other. The nuclear factor ÎșB (NF-ÎșB) pathway thereby plays a key role in linking metabolic and inflammatory programs in muscle cells. We conclude this review with a perspective about the consequences of such a negative crosstalk on the immune system and the possibilities this opens for clinical applications
Efeito da Energia, Relação Energia: ProteĂna e Fase de Crescimento Sobre o Desempenho e Composição de Carcaça de Frangos de Corte Effect of Energy, Energy: Protein Ratio and Growing Phase on The Performance and Carcass Composition of Broilers
Dois experimentos (EXP) avaliaram os efeitos da redução de proteĂna bruta (PB) em dietas com alta (A) (3.200kcal EM/kg) e baixa (B) (2.900kcal EM/kg) energia, sobre o desempenho e composição de carcaças de frangos de corte machos. Os nĂveis de PB foram reduzidos para obter as relaçÔes energia: proteĂna (E:PB) 139, 146, 153 e 160 (kcal/%) para as dietas iniciais (EXP 1), e 160, 167, 174 e 181(kcal/%) para as dietas de crescimento (EXP 2), em ambos os nĂveis de energia, mantendo constantes os nĂveis de MET+CIS e LIS. Todas as aves receberam uma mesma dieta antes (EXP 2) ou apĂłs (EXP 1) o fornecimento das dietas experimentais. O fornecimento das dietas A proporcionou melhor desempenho, no entanto resultou em maior deposição de gordura nas carcaças. No EXP 1, as aves alimentadas com as dietas B apresentaram ganho de peso (GP) similar Ă quelas alimentadas com as dietas A no perĂodo total (1 a 42 dias), porĂ©m melhor conversĂŁo calĂłrica (CC) (kcal/kg) (p<0,01). Foi observada tambĂ©m melhor CC, com relação E:PB 139. Menores nĂveis de PB dietĂ©tica resultaram, algumas vezes, em um menor GP, porĂ©m sempre foi verificada uma pior CC nas relaçÔes mais amplas E:PB. Em ambos os Experimentos (EXP), o maior nĂvel de energia e a redução da PB dietĂ©tica melhoraram a utilização da PB consumida.<br>Two experiments (EXP) were carried out to investigate the effects of crude protein (CP) levels reduction in high-energy (H) (3.200kcal ME/kg) and low-energy (L) (2.900kcal ME/kg) diets, on the performance and carcass composition of male broiler chickens. The CP levels were decreased to meet the following energy: protein (E:PB) ratios: 139, 146, 153 and 160 (kcal/%) for starter diets (EXP 1) and 160, 167, 174 and 181 (kcal/%) for grower diets (EXP 2), in both energy levels, keeping MET + CIS and LYS levels at the same concentration. All birds received a same diet before (EXP 2) or after (EXP 1) feeding the experimental diets. Feeding H diets resulted in better performance, but also in higher carcass fat deposition. In EXP 1, birds fed with L diets during the starter period had similar body weight gain (BWG), in the total period (1 to 42 days), than those H diets, however with better caloric conversion (kcal/kg) (CC). Also, the best CC was obtained with E:PB of 139. Lower BWG, sometimes occurred with lower levels of dietary CP, but in all experiments the CC was decreased with wider E:PB ration. In both EXP, protein utilization was improved with higher levels of dietary energy and with lower levels of dietary CP