Meslier Quentin A, Oehrlein Robert, Shefelbine Sandra J
Department of Bioengineering, Northeastern University, Boston, Massachusetts, USA.
Institute for Chemical Imaging of Living Systems, Northeastern University, Boston, Massachusetts, USA.
Aging Cell. 2025 Aug;24(8):e70087. doi: 10.1111/acel.70087. Epub 2025 May 23.
With age, bones mechanosensitivity is reduced, which limits their ability to adapt to loading. The exact mechanism leading to this loss of mechanosensitvity is still unclear, making developing effective treatment challenging. Current treatments mostly focus on preventing bone mass loss (such as bisphosphonates) or promoting bone formation (such as Sclerostin inhibitors) to limit the decline of bones mass. However, treatments do not target the cause of bone mass loss which may be, in part, due to the bone's inability to initiate a normal bone mechanoadaptation response. In this work, we investigated the effects of 2 weeks of tibia loading, and Piezo1 agonist injection in vivo on 22-month-old mouse bone adaptation response. We used an optimized loading profile, which induced high fluid flow velocity and low strain magnitude in adult mouse tibia. We found that tibia loading and Yoda2 injection have an additive effect on increasing cortical bone parameters in 22-month-old mice. In vivo osteocytes calcium signaling imaging suggests that Yoda2 is able to reach osteocytes and activate Piezo1. This combination of mechanical and chemical stimulation could be a promising treatment strategy to help promote bone formation in patients who have low bone mass due to aging.
随着年龄增长,骨骼的机械敏感性降低,这限制了它们适应负荷的能力。导致这种机械敏感性丧失的确切机制仍不清楚,这使得开发有效的治疗方法具有挑战性。目前的治疗大多集中在预防骨质流失(如双膦酸盐)或促进骨形成(如硬化蛋白抑制剂)以限制骨量下降。然而,这些治疗并未针对骨质流失的原因,部分原因可能是骨骼无法启动正常的骨机械适应反应。在这项研究中,我们研究了对22月龄小鼠进行为期2周的胫骨负荷以及在体内注射Piezo1激动剂对骨骼适应反应的影响。我们采用了优化的负荷模式,该模式在成年小鼠胫骨中诱导了高流体流速和低应变幅度。我们发现,胫骨负荷和Yoda2注射对增加22月龄小鼠的皮质骨参数具有累加效应。体内骨细胞钙信号成像表明,Yoda2能够到达骨细胞并激活Piezo1。这种机械和化学刺激的组合可能是一种有前景的治疗策略,有助于促进因衰老而骨量低的患者的骨形成。