Center for Biomechanical Research, Department of Mechanical Engineering, University of Delaware, 130 Academy Street, Newark, DE, 19716, USA.
Curr Osteoporos Rep. 2018 Feb;16(1):32-41. doi: 10.1007/s11914-018-0414-3.
Solute transport in the lacunar-canalicular system (LCS) plays important roles in osteocyte metabolism and cell-cell signaling. This review will summarize recent studies that establish pericellular matrix (PCM), discovered inside the LCS, as a crucial regulator of solute transport in bone.
Utilizing confocal imaging and mathematical modeling, recent studies successfully quantified molecular diffusion and convection in the LCS as well as the size-dependent sieving effects of the PCM, leading to the quantification of the effective PCM fiber spacing (10 to 17 nm) in murine adult bones. Perlecan/HSPG2, a large linear proteoglycan, was identified to be an essential PCM component. The PCM-filled LCS is bone's chromatographic column, where fluid/solute transport to and from the osteocytes is regulated. The chemical composition, deposition rate, and turnover rate of the osteocyte PCM should be further defined to better understand osteocyte physiology and bone metabolism.
腔隙-小管系统 (LCS) 中的溶质转运对于骨细胞代谢和细胞间信号传递具有重要作用。本文综述了最近的研究成果，这些研究将 LCS 内发现的细胞周基质 (PCM) 确立为骨骼中溶质转运的关键调节因子。
利用共聚焦成像和数学建模，最近的研究成功地量化了 LCS 中的分子扩散和对流以及 PCM 的尺寸依赖性筛分效应，从而定量确定了成年鼠骨中有效 PCM 纤维间隔（10 至 17nm）。核心蛋白聚糖/ HSPG2 是一种大型线性蛋白聚糖，被确定为必需的 PCM 成分。充满 PCM 的 LCS 是骨骼的色谱柱，其中流体/溶质向骨细胞和从骨细胞的转运受到调节。细胞周基质的化学组成、沉积率和周转率需要进一步确定，以更好地理解骨细胞生理学和骨代谢。
