BACKGROUND: Although osteoarthritis (OA) is a degenerative disease that is increasingly common with age, the pathogenesis of post-traumatic OA (PTOA) is poorly understood. This study aimed to undertake proteomics and bioinformatics analysis of cartilage in PTOA in a mini-pig model of anterior cruciate ligament repair (ACLR).

MATERIAL AND METHODS: The mini-pig model of PTOA involved autologous orthotopic ACLR. Screening and identification of differentially expressed proteins in the knee joint cartilage in the OA cartilage group were compared with the control group using tandem mass tag (TMT)-labeling liquid chromatography with tandem mass spectrometry (LC-MS-MS). A protein expression level >1.2 fold-change represented protein upregulation and <0.83 fold-change represented protein down-regulation Bioinformatics analysis included Gene Ontology (GO) functional annotation and the Kyoto Encyclopedia of Genes and Genome (KEGG) pathway enrichment analysis to determine the biological functions and pathways of proteins showing altered expression profiles associated with OA.

RESULTS: There were 2,950 proteins screened from the knee cartilage tissues of the OA model group using quantitative TMT-labeling LC-MS-MS. There were 491 proteins identified with altered expression profiles, 198 proteins were upregulated and 293 proteins were down-regulated in the OA cartilage group. GO function and KEGG pathway enrichment analysis of the 491 proteins identified their functions in cellular processes, metabolic processes, and biological regulation.

CONCLUSIONS: Proteomics and bioinformatics analysis of cartilage in PTOA in a mini-pig model of ACLR identified OA-related proteins.

Keywords: anterior cruciate ligament reconstruction, Osteoarthritis, Knee, Proteomics, Swine, Miniature, Anterior Cruciate Ligament, Anterior Cruciate Ligament Injuries, Cartilage, Articular, Computational Biology, gene ontology, Knee Joint, Osteoarthritis, Swine