Pathways of muscle protein breakdown in injury and sepsis.
The purpose of this article is to review evidence that the ubiquitin-proteasome proteolytic pathway plays an important role in injury- and sepsis-induced muscle catabolism. Such evidence includes upregulated gene expression of several of the components of the ubiquitin-proteasome pathway as well as energy-dependency of the injury- and sepsis-induced muscle protein breakdown. Although the ubiquitin-proteasome pathway is the predominant mechanism of muscle breakdown in various catabolic conditions, other proteolytic mechanisms, in particular calcium-dependent, calpain-mediated protein degradation, probably participate as well.
Hasselgren
P O
PO
Department of Surgery, University of Cincinnati, Ohio 45267-0558, USA. hasselp@uc.edu
D008841:Actin Cytoskeleton / Q000378:metabolism; D000818:Animals; D003546:Cysteine Endopeptidases / Q000235:genetics / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D006801:Humans; D006868:Hydrolysis; D009097:Multienzyme Complexes / Q000235:genetics / Q000378:metabolism; D009124:Muscle Proteins / Q000378:metabolism*; D046988:Proteasome Endopeptidase Complex; D018805:Sepsis / Q000378:metabolism*; D014452:Ubiquitins / Q000235:genetics / Q000378:metabolism; D014947:Wounds and Injuries / Q000378:metabolism*
D009097:Multienzyme Complexes; D009124:Muscle Proteins; D014452:Ubiquitins; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex