Animals in space exploration studies serve both as a model for human physiology and as a means to understand the physiological effects of microgravity. To quantify the microgravity-induced changes to bone health in animals, we systematically searched Medline, Embase, Web of Science, BIOSIS, and NASA Technical reports. We selected 40 papers focusing on the bone health of 95 rats, 61 mice, and 9 rhesus monkeys from 22 space missions. The percentage difference from ground control in rodents was –24.1% [Confidence interval: −43.4, −4.9] for trabecular bone volume fraction and –5.9% [−8.0, −3.8] for the cortical area. In primates, trabecular bone volume fraction was lower by –25.2% [−35.6, −14.7] in spaceflight animals compared to GC. Bone formation indices in rodent trabecular and cortical bone were significantly lower in microgravity. In contrast, osteoclast numbers were not affected in rats and were variably affected in mice. Thus, microgravity induces bone deficits in rodents and primates likely through the suppression of bone formation.

太空探索研究中的动物既可以作为人类生理学的模型，也可以作为理解微重力生理效应的一种手段。为了量化微重力引起的动物骨骼健康变化，我们系统地检索了 Medline、Embase、Web of Science、BIOSIS 和 NASA 技术报告。我们挑选了 40 篇论文，重点关注来自 22 次太空任务的 95 只大鼠、61 只小鼠和 9 只恒河猴的骨骼健康。啮齿类动物的骨小梁体积分数与地面对照的百分比差异为 –24.1% [置信区间：-43.4, -4.9]，皮质区域的百分比差异为 –5.9% [-8.0, -3.8]。在灵长类动物中，与 GC 相比，航天动物的骨小梁体积分数降低了 –25.2% [−35.6, −14.7]。啮齿动物小梁骨和皮质骨的骨形成指数在微重力下显着降低。相比之下，破骨细胞数量在大鼠中未受影响，但在小鼠中受到不同程度的影响。因此，微重力可能通过抑制骨形成而导致啮齿动物和灵长类动物的骨缺陷。