Department of Life Sciences, University of Siena, I-53100 Siena, Italy.
ASA Campus Joint Laboratory, ASA Research Division, Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, I-50139 Florence, Italy.
Int J Mol Sci. 2021 Apr 27;22(9):4585. doi: 10.3390/ijms22094585.
Microgravity-induced bone loss is currently a significant and unresolved health risk for space travelers, as it raises the likelihood for irreversible changes that weaken skeletal integrity and the incremental onset of fracture injuries and renal stone formation. Another issue related to bone tissue homeostasis in microgravity is its capacity to regenerate following fractures due to weakening of the tissue and accidental events during the accomplishment of particularly dangerous tasks. Today, several pharmacological and non-pharmacological countermeasures to this problem have been proposed, including physical exercise, diet supplements and administration of antiresorptive or anabolic drugs. However, each class of pharmacological agents presents several limitations as their prolonged and repeated employment is not exempt from the onset of serious side effects, which limit their use within a well-defined range of time. In this review, we will focus on the various countermeasures currently in place or proposed to address bone loss in conditions of microgravity, analyzing in detail the advantages and disadvantages of each option from a pharmacological point of view. Finally, we take stock of the situation in the currently available literature concerning bone loss and fracture healing processes. We try to understand which are the critical points and challenges that need to be addressed to reach innovative and targeted therapies to be used both in space missions and on Earth.
微重力导致的骨质流失目前是航天旅行者面临的一个重大且未得到解决的健康风险，因为它增加了骨骼完整性不可逆变化的可能性，导致骨折损伤和肾结石形成的风险逐渐增加。与微重力下骨组织平衡相关的另一个问题是，由于组织弱化和在执行特别危险任务时发生的意外事件，它在骨折后的再生能力。如今，已经提出了几种针对这个问题的药理学和非药理学对策，包括体育锻炼、饮食补充以及使用抗吸收或合成代谢药物。然而，每一类药理学药物都存在一些局限性，因为它们的长期和重复使用并不能免除严重副作用的发生，这限制了它们在明确时间范围内的使用。在这篇综述中，我们将重点讨论目前针对微重力条件下骨质流失的各种对策，从药理学角度详细分析每种选择的优缺点。最后，我们对目前关于骨质流失和骨折愈合过程的文献进行了评估。我们试图了解需要解决哪些关键点和挑战，以实现创新性和靶向治疗，不仅在太空任务中，而且在地球上也能使用。
