The aim of this study was to improve our understanding and the current treatment of denervation-induced skeletal muscle atrophy. We used isobaric tags for relative and absolute quantification (iTRAQ) coupled with two-dimensional liquid chromatography-tandem mass spectrometry (2D LC-MS/MS) to identify the differentially expressed proteins in the tibialis anterior (TA) muscle of rats at 1 and 4 w...

Cancer cachexia is a wasting condition, driven by systemic inflammation and oxidative stress. This study investigated eicosapentaenoic acid (EPA) in combination with oxypurinol as a treatment in a mouse model of cancer cachexia. Mice with cancer cachexia were randomized into 4 treatment groups (EPA (0.4 g/kg/day), oxypurinol (1 mmol/L ad-lib), combination, or control), and euthanized after 29 d...

Muscle protein breakdown (MPB) is increased following resistance exercise, but ingestion of carbohydrate during postexercise recovery can decrease MPB with no effect on muscle protein synthesis (MPS). We sought to determine whether a combination of essential amino acids (EAA) with low carbohydrate or high carbohydrate could effectively reduce MPB following resistance exercise and improve muscle...

The gain in muscle mass as a result of resistance training is dependent on changes in both anabolic and catabolic reactions. A frequency of two to three exercise sessions per week is considered optimal for muscle gain in untrained individuals. Our hypothesis was that a second exercise session would enlarge the anabolic response and/or decrease the catabolic response. Eight male subjects perform...

To test the hypothesis that creatine supplementation would enhance the anabolic responses of muscle cell signalling and gene expression to exercise, we studied nine subjects who received either creatine or a placebo (maltodextrin) for 5d in a doubleblind fashion before undergoing muscle biopsies: at rest; immediately after exercise (10×10 repetitions of one leg-extension at 80% 1-RM); and 24h a...

Cachexia is common in chronic inflammatory diseases and is attributed, in part, to elevation of circulating pro-inflammatory cytokines. TNF-α is the prototype in this category. IFN-γ is also thought to play a role, but the evidence supporting this model is primarily indirect. To determine the direct effects of IFN-γ stimulation on muscle cells, we selected key components of the pro-catabolic si...

BACKGROUND Skeletal muscle atrophy is a serious concern for the rehabilitation of patients afflicted by prolonged limb restriction. This debilitating condition is associated with a marked activation of NFκB activity. The ubiquitin-proteasome pathway degrades the NFκB inhibitor IκBα, enabling NFκB to translocate to the nucleus and bind to the target genes that promote muscle atrophy. Although se...

We tested whether NF-κB pathway is indispensable for the increase in expression of E3-ligases and unloading-induced muscle atrophy using IKKβ inhibitor IMD-0354. Three groups of rats were used: nontreated control (C), 3 days of unloading/hindlimb suspension with (HS+IMD) or without (HS) IMD-0354. Levels of IκBα were higher in HS+IMD (1.16-fold) and lower in HS (0.82-fold) when compared with C g...

We describe a new, simple immobilization protocol designed to induce muscle atrophy in lower hindlimb muscles in mice. Hindlimbs of C57BL6 mice were unilaterally immobilized for 7 days. Morphological analysis revealed that immobilization resulted in a significant reduction in muscle fiber size in both the extensor digitorum longus (EDL) and tibialis anterior (TA). By contrast, no significant ch...