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Proteome-wide analysis reveals an age-associated cellular phenotype of in situ aged human fibroblasts.

ABSTRACT: We analyzed an ex vivo model of in situ aged human dermal fibroblasts, obtained from 15 adult healthy donors from three different age groups using an unbiased quantitative proteome-wide approach applying label-free mass spectrometry. Thereby, we identified 2409 proteins, including 43 proteins with an age-associated abundance change. Most of the differentially abundant proteins have not been described in the context of fibroblasts' aging before, but the deduced biological processes confirmed known hallmarks of aging and led to a consistent picture of eight biological categories involved in fibroblast aging, namely proteostasis, cell cycle and proliferation, development and differentiation, cell death, cell organization and cytoskeleton, response to stress, cell communication and signal transduction, as well as RNA metabolism and translation. The exhaustive analysis of protein and mRNA data revealed that 77 % of the age-associated proteins were not linked to expression changes of the corresponding transcripts. This is in line with an associated miRNA study and led us to the conclusion that most of the age-associated alterations detected at the proteome level are likely caused post-transcriptionally rather than by differential gene expression. In summary, our findings led to the characterization of novel proteins potentially associated with fibroblast aging and revealed that primary cultures of in situ aged fibroblasts are characterized by moderate age-related proteomic changes comprising the multifactorial process of aging.

SUBMITTER: Waldera-Lupa DM

PROVIDER: S-EPMC4247387 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Proteome-wide analysis reveals an age-associated cellular phenotype of in situ aged human fibroblasts.

Waldera-Lupa Daniel M DM Kalfalah Faiza F Florea Ana-Maria AM Sass Steffen S Kruse Fabian F Rieder Vera V Tigges Julia J Fritsche Ellen E Krutmann Jean J Busch Hauke H Boerries Melanie M Meyer Helmut E HE Boege Fritz F Theis Fabian F Reifenberger Guido G Stühler Kai K

Aging 20141001 10

We analyzed an ex vivo model of in situ aged human dermal fibroblasts, obtained from 15 adult healthy donors from three different age groups using an unbiased quantitative proteome-wide approach applying label-free mass spectrometry. Thereby, we identified 2409 proteins, including 43 proteins with an age-associated abundance change. Most of the differentially abundant proteins have not been described in the context of fibroblasts' aging before, but the deduced biological processes confirmed know ...[more]

PMID: 25411231

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Proteome-wide analysis reveals an age-associated cellular phenotype of in situ aged human fibroblasts.

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Proteome-wide analysis reveals an age-associated cellular phenotype of in situ aged human fibroblasts.

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