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Expression and modification proteomics during skeletal muscle ageing

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Abstract

Skeletal muscle ageing is characterized by a progressive and dramatic loss of muscle mass and strength leading to decreased muscular function resulting in muscle weakness which is often referred to as sarcopenia. Following the standardisation of “omics” approaches to study the genome (genomics) and the transcriptome (transcriptomics), the study of the proteins encoded by the genome, referred to as proteomics, is a tremendous challenge. Unlike the genome, the proteome varies in response to many physiological or pathological factors. In addition, the proteome is orders of magnitude more complex than the transcriptome due to post-translational modifications, protein oxidation and limited protein degradation. Proteomic studies, including the analysis of protein abundance as well as post-translational modified proteins have been shown to provide valuable information to unravel the key molecular pathways implicated in complex biological processes, such as tissue and organ ageing. In this article, we will describe proteomic approaches for the analysis of protein abundance as well as the specific protein targets for oxidative damage upon oxidative stress and/or during skeletal muscle ageing.

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Acknowledgments

The authors are very thankful to the FP7 EU-funded project MyoAge (No. 223576), Inserm, UPMC, AFLD and the Association Française contre les Myopathies (AFM). M.A.B has received a post-doctoral fellowship from MyoAge and is currently the recipient of a post-doctoral fellowship from the Association Française contre les Myopathies (AFM). S.D. has received a post-doctoral fellowship from MyoAge. M.G. is supported by a PhD fellowship from the Conseil Régional Auvergne and Fonds Européens de Développement Régional (FEDER). The authors are grateful to Romain Ladouce for his expert assistance with the Oxi-DIGE.

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Baraibar, M.A., Gueugneau, M., Duguez, S. et al. Expression and modification proteomics during skeletal muscle ageing. Biogerontology 14, 339–352 (2013). https://doi.org/10.1007/s10522-013-9426-7

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