Department of Orthopedics, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China.
PLoS One. 2012;7(12):e52183. doi: 10.1371/journal.pone.0052183. Epub 2012 Dec 20.
A sudden mechanical insult to the spinal cord is usually caused by changing pressure on the surface of the spinal cord. Most of these insults are mechanical force injuries, and their mechanism of injury to the spinal cord is largely unknown.
Using a compression-driven instrument to simulate mechanical force, we applied mechanical pressure of 0.5 MPa to rat dorsal root ganglion (DRG) neurons for 10 min to investigate cytoskeletal alterations and calpain-induced apoptosis after the mechanical force injury.
The results indicated that mechanical forces affect the structure of the cytoskeleton and cell viability, induce early apoptosis, and affect the cell cycle of DRG neurons. In addition, the calpain inhibitor PD150606 reduced cytoskeletal degradation and the rate of apoptosis after mechanical force injury.
Thus, calpain may play an important role in DRG neurons in the regulation of apoptosis and cytoskeletal alterations induced by mechanical force. Moreover, cytoskeletal alterations may be substantially involved in the mechanotransduction process in DRG neurons after mechanical injury and may be induced by activated calpain. To our knowledge, this is the first report to demonstrate a relationship between cytoskeletal degradation and apoptosis in DRG neurons.
脊髓的突然机械损伤通常是由脊髓表面压力变化引起的。这些损伤大多是机械力损伤,其对脊髓的损伤机制在很大程度上尚不清楚。
使用压缩驱动仪器模拟机械力,我们对大鼠背根神经节(DRG)神经元施加 0.5 MPa 的机械压力 10 分钟,以研究机械力损伤后细胞骨架的改变和钙蛋白酶诱导的细胞凋亡。
结果表明,机械力影响细胞骨架的结构和细胞活力,诱导早期凋亡,并影响 DRG 神经元的细胞周期。此外,钙蛋白酶抑制剂 PD150606 减少了机械力损伤后细胞骨架的降解和凋亡率。
因此,钙蛋白酶可能在机械力诱导的 DRG 神经元凋亡和细胞骨架改变的调节中发挥重要作用。此外,细胞骨架的改变可能在机械损伤后 DRG 神经元的机械转导过程中起重要作用,并且可能是由激活的钙蛋白酶引起的。据我们所知,这是首次证明 DRG 神经元中细胞骨架降解与凋亡之间存在关系的报告。