Local origins impart conserved bone type-related differences in human osteoblast behaviour

Shah, M; Gburcik, V; Reilly, P; Sankey, R A; Emery, R J; Clarkin, C E; Pitsillides, A A

Abstract

Osteogenic behaviour of osteoblasts from trabecular, cortical and subchondral bone were examined to determine any bone type-selective differences in samples from both osteoarthritic (OA) and osteoporotic (OP) patients. Cell growth, differentiation; alkaline phosphatase (TNAP) mRNA and activity, Runt-related transcription factor-2 (RUNX2), SP7-transcription factor (SP7), bone sialoprotein-II (BSP-II), osteocalcin/bone gamma-carboxyglutamate (BGLAP), osteoprotegerin (OPG, TNFRSF11B), receptor activator of nuclear factor-κβ ligand (RANKL, TNFSF11) mRNA levels and proangiogenic vascular endothelial growth factor-A (VEGF-A) mRNA and protein release were assessed in osteoblasts from paired humeral head samples from age-matched, human OA/OP (n = 5/4) patients. Initial outgrowth and increase in cell number were significantly faster (p < 0.01) in subchondral and cortical than trabecular osteoblasts, in OA and OP, and this bone type-related differences were conserved despite consistently faster growth in OA. RUNX2/SP7 levels and TNAP mRNA and protein activity were, however, greater in trabecular than subchondral and cortical osteoblasts in OA and OP. BSP-II levels were significantly greater in trabecular and lowest in cortical osteoblasts in both OA and OP. In contrast, BGLAP levels showed divergent bone type-selective behaviour; highest in osteoblasts from subchondral origins in OA and trabecular origins in OP. We found virtually identical bone type-related differences, however, in TNFRSF11B:TNFSF11 in OA and OP, consistent with greater potential for paracrine effects on osteoclasts in trabecular osteoblasts. Subchondral osteoblasts (OA) exhibited highest VEGF-A mRNA levels and release. Our data indicate that human osteoblasts in trabecular, subchondral and cortical bone have inherent, programmed diversity, with specific bone type-related differences in growth, differentiation and pro-angiogenic potential in vitro.

Citation

Shah, M., Gburcik, V., Reilly, P., Sankey, R. A., Emery, R. J., Clarkin, C. E., & Pitsillides, A. A. (2015). Local origins impart conserved bone type-related differences in human osteoblast behaviour. https://doi.org/10.22203/eCM.v029a12

• Journal Article Type: Article
• Acceptance Date: Jan 20, 2015
• Publication Date: Mar 4, 2015
• Deposit Date: Mar 13, 2015
• Publicly Available Date: Mar 13, 2015
• Journal: EUROPEAN CELLS & MATERIALS
• Peer Reviewed: Peer Reviewed
• Volume: 29
• Pages: 155-176
• DOI: https://doi.org/10.22203/eCM.v029a12
• Public URL: https://rvc-repository.worktribe.com/output/1401657