Cargando…

Osteocytic Pericellular Matrix (PCM): Accelerated Degradation under In Vivo Loading and Unloading Conditions Using a Novel Imaging Approach

The proteoglycan-containing pericellular matrix (PCM) controls both the biophysical and biochemical microenvironment of osteocytes, which are the most abundant cells embedded and dispersed in bones. As a molecular sieve, osteocytic PCMs not only regulate mass transport to and from osteocytes but als...

Descripción completa

Detalles Bibliográficos
Autores principales: Pei, Shaopeng, Wang, Shubo, Martinez, Jerahme R., Parajuli, Ashutosh, Kirn-Safran, Catherine B., Farach-Carson, Mary C., Lu, X. Lucas, Wang, Liyun
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8775093/
https://www.ncbi.nlm.nih.gov/pubmed/35052411
http://dx.doi.org/10.3390/genes13010072
_version_ 1784636499173572608
author Pei, Shaopeng
Wang, Shubo
Martinez, Jerahme R.
Parajuli, Ashutosh
Kirn-Safran, Catherine B.
Farach-Carson, Mary C.
Lu, X. Lucas
Wang, Liyun
author_facet Pei, Shaopeng
Wang, Shubo
Martinez, Jerahme R.
Parajuli, Ashutosh
Kirn-Safran, Catherine B.
Farach-Carson, Mary C.
Lu, X. Lucas
Wang, Liyun
author_sort Pei, Shaopeng
collection PubMed
description The proteoglycan-containing pericellular matrix (PCM) controls both the biophysical and biochemical microenvironment of osteocytes, which are the most abundant cells embedded and dispersed in bones. As a molecular sieve, osteocytic PCMs not only regulate mass transport to and from osteocytes but also act as sensors of external mechanical environments. The turnover of osteocytic PCM remains largely unknown due to technical challenges. Here, we report a novel imaging technique based on metabolic labeling and “click-chemistry,” which labels de novo PCM as “halos” surrounding osteocytes in vitro and in vivo. We then tested the method and showed different labeling patterns in young vs. old bones. Further “pulse-chase” experiments revealed dramatic difference in the “half-life” of PCM of cultured osteocytes (~70 h) and that of osteocytes in vivo (~75 d). When mice were subjected to either 3-week hindlimb unloading or 7-week tibial loading (5.1 N, 4 Hz, 3 d/week), PCM half-life was shortened (~20 d) and degradation accelerated. Matrix metallopeptidase MMP-14 was elevated in mechanically loaded osteocytes, which may contribute to PCM degradation. This study provides a detailed procedure that enables semi-quantitative study of the osteocytic PCM remodeling in vivo and in vitro.
format Online
Article
Text
id pubmed-8775093
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher MDPI
record_format MEDLINE/PubMed
spelling pubmed-87750932022-01-21 Osteocytic Pericellular Matrix (PCM): Accelerated Degradation under In Vivo Loading and Unloading Conditions Using a Novel Imaging Approach Pei, Shaopeng Wang, Shubo Martinez, Jerahme R. Parajuli, Ashutosh Kirn-Safran, Catherine B. Farach-Carson, Mary C. Lu, X. Lucas Wang, Liyun Genes (Basel) Article The proteoglycan-containing pericellular matrix (PCM) controls both the biophysical and biochemical microenvironment of osteocytes, which are the most abundant cells embedded and dispersed in bones. As a molecular sieve, osteocytic PCMs not only regulate mass transport to and from osteocytes but also act as sensors of external mechanical environments. The turnover of osteocytic PCM remains largely unknown due to technical challenges. Here, we report a novel imaging technique based on metabolic labeling and “click-chemistry,” which labels de novo PCM as “halos” surrounding osteocytes in vitro and in vivo. We then tested the method and showed different labeling patterns in young vs. old bones. Further “pulse-chase” experiments revealed dramatic difference in the “half-life” of PCM of cultured osteocytes (~70 h) and that of osteocytes in vivo (~75 d). When mice were subjected to either 3-week hindlimb unloading or 7-week tibial loading (5.1 N, 4 Hz, 3 d/week), PCM half-life was shortened (~20 d) and degradation accelerated. Matrix metallopeptidase MMP-14 was elevated in mechanically loaded osteocytes, which may contribute to PCM degradation. This study provides a detailed procedure that enables semi-quantitative study of the osteocytic PCM remodeling in vivo and in vitro. MDPI 2021-12-28 /pmc/articles/PMC8775093/ /pubmed/35052411 http://dx.doi.org/10.3390/genes13010072 Text en © 2021 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Pei, Shaopeng
Wang, Shubo
Martinez, Jerahme R.
Parajuli, Ashutosh
Kirn-Safran, Catherine B.
Farach-Carson, Mary C.
Lu, X. Lucas
Wang, Liyun
Osteocytic Pericellular Matrix (PCM): Accelerated Degradation under In Vivo Loading and Unloading Conditions Using a Novel Imaging Approach
title Osteocytic Pericellular Matrix (PCM): Accelerated Degradation under In Vivo Loading and Unloading Conditions Using a Novel Imaging Approach
title_full Osteocytic Pericellular Matrix (PCM): Accelerated Degradation under In Vivo Loading and Unloading Conditions Using a Novel Imaging Approach
title_fullStr Osteocytic Pericellular Matrix (PCM): Accelerated Degradation under In Vivo Loading and Unloading Conditions Using a Novel Imaging Approach
title_full_unstemmed Osteocytic Pericellular Matrix (PCM): Accelerated Degradation under In Vivo Loading and Unloading Conditions Using a Novel Imaging Approach
title_short Osteocytic Pericellular Matrix (PCM): Accelerated Degradation under In Vivo Loading and Unloading Conditions Using a Novel Imaging Approach
title_sort osteocytic pericellular matrix (pcm): accelerated degradation under in vivo loading and unloading conditions using a novel imaging approach
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8775093/
https://www.ncbi.nlm.nih.gov/pubmed/35052411
http://dx.doi.org/10.3390/genes13010072
work_keys_str_mv AT peishaopeng osteocyticpericellularmatrixpcmaccelerateddegradationunderinvivoloadingandunloadingconditionsusinganovelimagingapproach
AT wangshubo osteocyticpericellularmatrixpcmaccelerateddegradationunderinvivoloadingandunloadingconditionsusinganovelimagingapproach
AT martinezjerahmer osteocyticpericellularmatrixpcmaccelerateddegradationunderinvivoloadingandunloadingconditionsusinganovelimagingapproach
AT parajuliashutosh osteocyticpericellularmatrixpcmaccelerateddegradationunderinvivoloadingandunloadingconditionsusinganovelimagingapproach
AT kirnsafrancatherineb osteocyticpericellularmatrixpcmaccelerateddegradationunderinvivoloadingandunloadingconditionsusinganovelimagingapproach
AT farachcarsonmaryc osteocyticpericellularmatrixpcmaccelerateddegradationunderinvivoloadingandunloadingconditionsusinganovelimagingapproach
AT luxlucas osteocyticpericellularmatrixpcmaccelerateddegradationunderinvivoloadingandunloadingconditionsusinganovelimagingapproach
AT wangliyun osteocyticpericellularmatrixpcmaccelerateddegradationunderinvivoloadingandunloadingconditionsusinganovelimagingapproach