 Focusing our attention during exacerbations, a period of aggravated systemic inflammation, should be more rewarding in terms of understanding the link between inflammation burst and muscle disease in COPD. We have recently acquired experimental data supporting a role for the ubiquitin proteasome pathway in the worsening of limb muscle structure and function during an acute exacerbation, providing a solid framework for this investigation. The overall objective of this proposal is to substantiate these preliminary findings and elucidate how systemic inflammation during acute COPD exacerbation may affect limb muscles. Ultimately, our research could open new therapeutic avenues to minimize the systemic consequences of an acute exacerbation. 