PDF(Pubmed)
Abstract：
Osteocytes locally remodel their surrounding tissue through perilacunar canalicular remodeling (PLR). During lactation, osteocytes remove minerals to satisfy the metabolic demand, resulting in increased lacunar volume, quantifiable with synchrotron X-ray radiation micro-tomography (SRµCT). Although the effects of lactation on PLR are well-studied, it remains unclear whether PLR occurs uniformly throughout the bone and what mechanisms prevent PLR from undermining bone quality. We used SRµCT imaging to conduct an in-depth spatial analysis of the impact of lactation and osteocyte-intrinsic MMP13 deletion on PLR in murine bone. We found larger lacunae undergoing PLR are located near canals in the mid-cortex or endosteum. We show lactation-induced hypomineralization occurs 14 µm away from lacunar edges, past a hypermineralized barrier. Our findings reveal that osteocyte-intrinsic MMP13 is crucial for lactation-induced PLR near lacunae in the mid-cortex but not for whole-bone resorption. This research highlights the spatial control of PLR on mineral distribution during lactation.
摘要：
骨细胞通过周围小管重塑（PLR）局部重塑其周围组织。哺乳期,骨细胞去除矿物质以满足代谢需求，导致腔隙体积增加，用同步加速器X射线辐射显微断层扫描(SRµCT)可量化。虽然对泌乳对PLR的影响进行了充分的研究，目前尚不清楚PLR是否在整个骨骼中均匀发生,以及什么机制阻止PLR破坏骨骼质量.我们使用SRµCT成像对泌乳和骨细胞固有MMP13缺失对鼠骨PLR的影响进行了深入的空间分析。我们发现接受PLR的较大腔隙位于中部皮质或内皮的运河附近。我们显示泌乳诱导的低矿化发生在距腔隙边缘14µm处，经过高度矿化的屏障。我们的发现表明，骨细胞固有的MMP13对于泌乳诱导的中部皮质腔隙附近的PLR至关重要，而对于全骨吸收则不是。这项研究强调了PLR对泌乳期矿物质分布的空间控制。
