期刊论文详细信息
Clinical Proteomics
Comparative proteomic analysis of hypertrophic chondrocytes in osteoarthritis
Anastassios Economou4  Aspasia Tsezou3  Michalis Zervakis2  Konstantinos Malizos1  Kalliopi Kalantzaki2  Vassiliki Gkretsi3  Fotini Kostopoulou3  Ioanna Papathanasiou3  Ekaterini S Bei2  Konstantinos C Tsolis4 
[1] Department of Orthopedics, University of Thessaly, Faculty of Medicine, Larissa, Greece;School of Electronic and Computer Engineering, Technical Univ. of Crete, Chania, Greece;Institute for Research & Technology-Thessaly/Centre for Research & Technology-Hellas (CE.R.T.H), Larissa, Greece;Department of Microbiology and Immunology, Rega Institute for Medical Research, KULeuven, Leuven, Belgium
关键词: GSTP1;    PLS3;    Pathway analysis;    Mass spectrometry;    Proteomics;    Chondrocytes;    Cartilage;    Osteoarthritis;   
Others  :  1180321
DOI  :  10.1186/s12014-015-9085-6
 received in 2015-02-17, accepted in 2015-04-15,  发布年份 2015
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【 摘 要 】

Background

Osteoarthritis (OA) is a multi-factorial disease leading progressively to loss of articular cartilage and subsequently to loss of joint function. While hypertrophy of chondrocytes is a physiological process implicated in the longitudinal growth of long bones, hypertrophy-like alterations in chondrocytes play a major role in OA. We performed a quantitative proteomic analysis in osteoarthritic and normal chondrocytes followed by functional analyses to investigate proteome changes and molecular pathways involved in OA pathogenesis.

Methods

Chondrocytes were isolated from articular cartilage of ten patients with primary OA undergoing knee replacement surgery and six normal donors undergoing fracture repair surgery without history of joint disease and no OA clinical manifestations. We analyzed the proteome of chondrocytes using high resolution mass spectrometry and quantified it by label-free quantification and western blot analysis. We also used WebGestalt, a web-based enrichment tool for the functional annotation and pathway analysis of the differentially synthesized proteins, using the Wikipathways database. ClueGO, a Cytoscape plug-in, is also used to compare groups of proteins and to visualize the functionally organized Gene Ontology (GO) terms and pathways in the form of dynamical network structures.

Results

The proteomic analysis led to the identification of a total of ~2400 proteins. 269 of them showed differential synthesis levels between the two groups. Using functional annotation, we found that proteins belonging to pathways associated with regulation of the actin cytoskeleton, EGF/EGFR, TGF-β, MAPK signaling, integrin-mediated cell adhesion, and lipid metabolism were significantly enriched in the OA samples (p ≤10−5). We also observed that the proteins GSTP1, PLS3, MYOF, HSD17B12, PRDX2, APCS, PLA2G2A SERPINH1/HSP47 and MVP, show distinct synthesis levels, characteristic for OA or control chondrocytes.

Conclusion

In this study we compared the quantitative changes in proteins synthesized in osteoarthritic compared to normal chondrocytes. We identified several pathways and proteins to be associated with OA chondrocytes. This study provides evidence for further testing on the molecular mechanism of the disease and also propose proteins as candidate markers of OA chondrocyte phenotype.

【 授权许可】

   
2015 Tsolis et al.; licensee BioMed Central.

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