The Impact of the Extracellular Matrix Environment on <i>Sost</i> Expression by the MLO-Y4 Osteocyte Cell Line
Bone is a dynamic organ that can adapt its structure to meet the demands of its biochemical and biophysical environment. Osteocytes form a sensory network throughout the tissue and orchestrate tissue adaptation via the release of soluble factors such as a sclerostin. Osteocyte physiology has traditi...
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| Format: | Article |
| Language: | English |
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MDPI AG
2022-01-01
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| Series: | Bioengineering |
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| Online Access: | https://www.mdpi.com/2306-5354/9/1/35 |
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| author | Robert T. Brady Fergal J. O’Brien David A. Hoey |
| author_facet | Robert T. Brady Fergal J. O’Brien David A. Hoey |
| author_sort | Robert T. Brady |
| collection | DOAJ |
| description | Bone is a dynamic organ that can adapt its structure to meet the demands of its biochemical and biophysical environment. Osteocytes form a sensory network throughout the tissue and orchestrate tissue adaptation via the release of soluble factors such as a sclerostin. Osteocyte physiology has traditionally been challenging to investigate due to the uniquely mineralized extracellular matrix (ECM) of bone leading to the development of osteocyte cell lines. Importantly, the most widely researched and utilized osteocyte cell line: the MLO-Y4, is limited by its inability to express sclerostin (<i>Sost</i> gene) in typical in-vitro culture. We theorised that culture in an environment closer to the in vivo osteocyte environment could impact on <i>Sost</i> expression. Therefore, this study investigated the role of composition and dimensionality in directing <i>Sost</i> expression in MLO-Y4 cells using collagen-based ECM analogues. A significant outcome of this study is that MLO-Y4 cells, when cultured on a hydroxyapatite (HA)-containing two-dimensional (2D) film analogue, expressed <i>Sost</i>. Moreover, three-dimensional (3D) culture within HA-containing collagen scaffolds significantly enhanced <i>Sost</i> expression, demonstrating the impact of ECM composition and dimensionality on MLO-Y4 behaviour. Importantly, in this bone mimetic ECM environment, <i>Sost</i> expression was found to be comparable to physiological levels. Lastly, MLO-Y4 cells cultured in these novel conditions responded accordingly to fluid flow stimulation with a decrease in expression. This study therefore presents a novel culture system for the MLO-Y4 osteocyte cell line, ensuring the expression of an important osteocyte specific gene, <i>Sost</i>, overcoming a major limitation of this model. |
| first_indexed | 2024-03-10T01:54:40Z |
| format | Article |
| id | doaj.art-14e3d7a58f0e44a29858ff64f79dc4de |
| institution | Directory Open Access Journal |
| issn | 2306-5354 |
| language | English |
| last_indexed | 2024-03-10T01:54:40Z |
| publishDate | 2022-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Bioengineering |
| spelling | doaj.art-14e3d7a58f0e44a29858ff64f79dc4de2023-11-23T12:59:24ZengMDPI AGBioengineering2306-53542022-01-01913510.3390/bioengineering9010035The Impact of the Extracellular Matrix Environment on <i>Sost</i> Expression by the MLO-Y4 Osteocyte Cell LineRobert T. Brady0Fergal J. O’Brien1David A. Hoey2Tissue Engineering Research Group, Department of Anatomy & Regenerative Medicine, Royal College of Surgeons in Ireland, D02 YN77 Dublin, IrelandTissue Engineering Research Group, Department of Anatomy & Regenerative Medicine, Royal College of Surgeons in Ireland, D02 YN77 Dublin, IrelandTrinity Centre for Biomedical Engineering, School of Engineering, Trinity College Dublin, D02 PN40 Dublin, IrelandBone is a dynamic organ that can adapt its structure to meet the demands of its biochemical and biophysical environment. Osteocytes form a sensory network throughout the tissue and orchestrate tissue adaptation via the release of soluble factors such as a sclerostin. Osteocyte physiology has traditionally been challenging to investigate due to the uniquely mineralized extracellular matrix (ECM) of bone leading to the development of osteocyte cell lines. Importantly, the most widely researched and utilized osteocyte cell line: the MLO-Y4, is limited by its inability to express sclerostin (<i>Sost</i> gene) in typical in-vitro culture. We theorised that culture in an environment closer to the in vivo osteocyte environment could impact on <i>Sost</i> expression. Therefore, this study investigated the role of composition and dimensionality in directing <i>Sost</i> expression in MLO-Y4 cells using collagen-based ECM analogues. A significant outcome of this study is that MLO-Y4 cells, when cultured on a hydroxyapatite (HA)-containing two-dimensional (2D) film analogue, expressed <i>Sost</i>. Moreover, three-dimensional (3D) culture within HA-containing collagen scaffolds significantly enhanced <i>Sost</i> expression, demonstrating the impact of ECM composition and dimensionality on MLO-Y4 behaviour. Importantly, in this bone mimetic ECM environment, <i>Sost</i> expression was found to be comparable to physiological levels. Lastly, MLO-Y4 cells cultured in these novel conditions responded accordingly to fluid flow stimulation with a decrease in expression. This study therefore presents a novel culture system for the MLO-Y4 osteocyte cell line, ensuring the expression of an important osteocyte specific gene, <i>Sost</i>, overcoming a major limitation of this model.https://www.mdpi.com/2306-5354/9/1/35osteocyteMLO-Y4bonecompositiondimensionality3D |
| spellingShingle | Robert T. Brady Fergal J. O’Brien David A. Hoey The Impact of the Extracellular Matrix Environment on <i>Sost</i> Expression by the MLO-Y4 Osteocyte Cell Line Bioengineering osteocyte MLO-Y4 bone composition dimensionality 3D |
| title | The Impact of the Extracellular Matrix Environment on <i>Sost</i> Expression by the MLO-Y4 Osteocyte Cell Line |
| title_full | The Impact of the Extracellular Matrix Environment on <i>Sost</i> Expression by the MLO-Y4 Osteocyte Cell Line |
| title_fullStr | The Impact of the Extracellular Matrix Environment on <i>Sost</i> Expression by the MLO-Y4 Osteocyte Cell Line |
| title_full_unstemmed | The Impact of the Extracellular Matrix Environment on <i>Sost</i> Expression by the MLO-Y4 Osteocyte Cell Line |
| title_short | The Impact of the Extracellular Matrix Environment on <i>Sost</i> Expression by the MLO-Y4 Osteocyte Cell Line |
| title_sort | impact of the extracellular matrix environment on i sost i expression by the mlo y4 osteocyte cell line |
| topic | osteocyte MLO-Y4 bone composition dimensionality 3D |
| url | https://www.mdpi.com/2306-5354/9/1/35 |
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