Department of Physiology, Gifu University Graduate School of Medicine, 1-1 Yanagido, Gifu, 501-1194, Japan.
Interdisciplinary Biology Laboratory (iBLab), Division of Natural Science, Graduate School of Science, Nagoya University, Aichi, Japan.
J Physiol Sci. 2024 Sep 18;74(1):44. doi: 10.1186/s12576-024-00939-y.
Gravity has profoundly influenced life on Earth, yet how organisms adapt to changes in gravity remains largely unknown. This study examines vestibular plasticity, specifically how the vestibular system responds to altered gravity. We subjected male C57BL/6J mice to hypergravity (2 G) followed by normal gravity (1 G) to analyze changes in vestibular function and gene expression. Mice showed significant vestibular dysfunction, assessed by righting reflex tests, which persisted for days but reversed at 1 G after exposure to 2 G. Gene expression analysis in the vestibular ganglion identified significant changes in 212 genes out of 49,585 due to gravitational changes. Specifically, 25 genes were upregulated under 2 G and recovered at 1 G after 2 G exposure, while one gene showed the opposite trend. Key neural function genes like Shisa3, Slc25a37, Ntn4, and Snca were involved. Our results reveal that hypergravity-induced vestibular dysfunction is reversible and highlight genes critical for adaptation.
重力对地球上的生命有深远的影响，但生物体如何适应重力变化在很大程度上仍是未知的。本研究探讨了前庭可塑性，特别是前庭系统如何对改变的重力做出反应。我们让雄性 C57BL/6J 小鼠经历超重力（2G），然后是正常重力（1G），以分析前庭功能和基因表达的变化。通过翻正反射测试评估，小鼠表现出明显的前庭功能障碍，这种障碍持续数天，但在暴露于 2G 后在 1G 时逆转。由于重力变化，前庭神经节中的基因表达分析确定了 49585 个基因中有 212 个发生了显著变化。具体来说，在 2G 下有 25 个基因上调，并在 2G 暴露后在 1G 下恢复，而一个基因则呈现相反的趋势。涉及到关键的神经功能基因，如 Shisa3、Slc25a37、Ntn4 和 Snca。我们的结果表明，超重力引起的前庭功能障碍是可逆的，并强调了适应过程中关键的基因。
