A proteomic analysis of chondrogenic, osteogenic and tenogenic constructs from ageing mesenchymal stem cells.
Mesenchymal stem cells (MSCs) have prospective applications in regenerative medicine and tissue engineering but to what extent phenotype and differentiation capacity alter with ageing is uncertain. Consequently, any loss in functionality with age would have profound consequences for the maintenance of tissue viability and the quality of tissues. Proteomics enables the set of proteins responsible for a particular cell phenotype to be identified, as well as enabling insights into mechanisms responsible for age-related alterations in musculoskeletal tissues. Few proteomic studies have been undertaken regarding age-related effects on tissue engineered into cartilage and bone, and none for tendon. This study provides a proteome inventory for chondrogenic, osteogenic and tenogenic constructs synthesised from human MSCs, and elucidates proteomic alterations as a consequence of donor age.



Human bone-marrow derived MSCs from young (n = 4, 21.8 years ± 2.4SD) and old (n = 4, 65.5 years ± 8.3SD) donors were used to make chondrogenic, osteogenic and tenogenic tissue-engineered constructs. We utilised an analytical method relying on extracted peptide intensities as a label-free approach for peptide quantitation by liquid chromatography-mass spectrometry. Results were validated using western blotting.



We identified proteins that were differentially expressed with ageing; 128 proteins in chondrogenic constructs, 207 in tenogenic constructs and four in osteogenic constructs. Differentially regulated proteins were subjected to bioinformatic analysis to ascertain their molecular functions and the signalling pathways. For all construct types, age-affected proteins were involved in altered cell survival and death, and antioxidant and cytoskeletal changes. Energy and protein metabolism were the principle pathways affected in tenogenic constructs, whereas lipid metabolism was strongly affected in chondrogenic constructs and mitochondrial dysfunction in osteogenic constructs.



Our results imply that further work on MSC-based therapeutics for the older population needs to focus on oxidative stress protection. The differentially regulated proteome characterised by this study can potentially guide translational research specifically aimed at effective clinical interventions.
Institute of Ageing and Chronic Disease, University of Liverpool, Leahurst, Chester High Road, Neston, CH64 7TE, UK. peffs@liv.ac.uk.|Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, The University of Liverpool, Leahurst, Neston, CH64 7TE, UK. peffs@liv.ac.uk.
Mandy J
MJ
Peffers
Institute of Ageing and Chronic Disease, University of Liverpool, Leahurst, Chester High Road, Neston, CH64 7TE, UK.
John
J
Collins
Musculoskeletal Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
John
J
Loughlin
Musculoskeletal Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.|Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne, NE4 5PL, UK.
Carole
C
Proctor
Institute of Ageing and Chronic Disease, University of Liverpool, Leahurst, Chester High Road, Neston, CH64 7TE, UK.
Peter D
PD
Clegg
D000328:Adult; D000368:Aged; D000375:Aging / Q000378:metabolism* / Q000502:physiology; D001854:Bone Marrow Cells / Q000378:metabolism* / Q000502:physiology; D001842:Bone and Bones / Q000378:metabolism / Q000502:physiology; D002356:Cartilage / Q000378:metabolism / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D019902:Chondrocytes / Q000378:metabolism / Q000502:physiology; D020219:Chondrogenesis / Q000502:physiology*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000378:metabolism* / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology*; D011446:Prospective Studies; D040901:Proteomics / Q000379:methods; D044968:Regenerative Medicine / Q000379:methods; D013710:Tendons / Q000378:metabolism* / Q000502:physiology; D023822:Tissue Engineering / Q000379:methods; D055815:Young Adult
Ageing; Chondrogenesis; Label-free quantification; Mesenchymal stem cells; Osteogenesis; Oxidative stress; Tenogenesis