Biology Department, Mount Saint Vincent University, 166 Bedford Highway, Halifax, NS, Canada.
Dev Genes Evol. 2022 Aug;232(2-4):67-79. doi: 10.1007/s00427-022-00691-6. Epub 2022 Jul 8.
Mechanical influencers have long been shown to affect mature bone. Bone mechanosensation is a key feature that allows the skeleton to adapt to environmental constraints. In this study, we describe the response of immature, developing bones to a mechanical stimulus. To do so, zebrafish larvae at different stages of development were exposed to whole-body vibration (WBV) at a low frequency of 20 Hz, for up to 4 days. Whole mount Alizarin red and Alcian blue staining revealed age-related and bone type-specific defects. Specifically, the parhypural and hypural 1 caudal fin endoskeletal elements were affected when the exposure to WBV started early during their development. We show that these WBV-induced parhypural and hypural 1 patterning defects are triggered by a Sox9-independent pathway, potentially by reducing the distance separating adjacent chondrogenic condensations in the developing tail skeleton. The remaining hypurals were unaffected by the WBV treatment. Altogether, our results indicate that, upon exposure to vibration, chondrogenic cell progenitors can react to mechanical stimuli early during their development, which ultimately affects the skeletal patterning of the growing zebrafish larvae. These findings open a new research avenue to better understand the cellular processes involved in developing, patterning, and maintaining skeletal tissue.
机械因素长期以来一直被证明会影响成熟骨骼。骨骼机械感知是骨骼适应环境约束的关键特征。在这项研究中，我们描述了不成熟的发育中的骨骼对机械刺激的反应。为此，我们将处于不同发育阶段的斑马鱼幼虫暴露于 20 Hz 的低频全身振动（WBV）中，最长可达 4 天。整体 Alizarin 红和 Alcian 蓝染色显示出与年龄相关的和骨类型特异性的缺陷。具体而言，当 WBV 在其发育早期开始时，尾鳍的副半椎骨和第 1 个尾椎骨内骨骼元素受到影响。我们表明，这些由 WBV 引起的副半椎骨和第 1 个尾椎骨的模式缺陷是由 Sox9 非依赖性途径触发的，可能是通过减小发育中尾巴骨骼中相邻软骨形成凝聚物之间的距离。其余的尾椎骨不受 WBV 处理的影响。总之，我们的研究结果表明，在暴露于振动后，软骨祖细胞可以在其发育的早期对机械刺激做出反应，这最终会影响生长中的斑马鱼幼虫的骨骼模式形成。这些发现为更好地理解参与发育、模式形成和维持骨骼组织的细胞过程开辟了新的研究途径。
