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Updated: May 28, 2026

Isolation, Characterization, and Purification of Macrophages from Tissues Affected by Obesity-related Inflammation
Published on: April 3, 2017
Effects of malnutrition with or without eicosapentaenoic acid on proteolytic pathways in diaphragm
Joanne M Bando1, Mario Fournier, Xiaoyu Da
1Division of Pulmonary/Critical Care Medicine, The Burns & Allen Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, United States.
Abstract:
Attenuation of muscle wasting has been reported with eicosapentaenoic acid (EPA) use in cachectic states. Pathways mediating muscle proteolysis with severe short-term nutritional deprivation (ND)±EPA were evaluated, including diaphragm fiber-specific cross-sectional areas, mRNA (real-time PCR) and protein expression (Western blot). Rats were divided into three groups: (1) free-eating controls, (2) ND and (3) ND+EPA. ND significantly influenced multiple proteolytic pathways. EPA significantly reduced mRNA abundances for most genes to control levels with ND. However, discordant muscle protein expression of many genes was noted with the use of EPA, as protein levels failed to fall. EPA had no impact on diaphragm muscle atrophy, despite the impressive mRNA and some protein results. We conclude that EPA does not attenuate diaphragm muscle atrophy with severe levels of ND. Postulated mechanisms include reduction in muscle protein synthesis and persistent ongoing stimuli for proteolysis. Our study provides unique data on proteolytic signals with ND and has important implications for future studies using EPA.
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