Department of Cardiothoracic Surgery, Northern Jiangsu People's Hospital, Yangzhou University, Yangzhou, China; Department of Cardiothoracic Surgery, Children's Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China.
Department of Cardiothoracic Surgery, Children's Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China.
Cryobiology. 2023 Sep;112:104544. doi: 10.1016/j.cryobiol.2023.05.001. Epub 2023 May 19.
Mild hypothermia is proven neuroprotective in clinical practice. While hypothermia leads to the decrease of global protein synthesis rate, it upregulates a small subset of protein including RNA-binding motif protein 3 (RBM3). In this study, we treated mouse neuroblastoma cells (N2a) with mild hypothermia before oxygen-glucose deprivation/reoxygenation (OGD/R) and discovered the decrease of apoptosis rate, down-regulation of apoptosis-associated protein and enhancement of cell viability. Overexpression of RBM3 via plasmid exerted similar effect while silencing RBM3 by siRNAs partially reversed the protective effect exerted by mild hypothermia pretreatment. The protein level of Reticulon 3(RTN3), a downstream gene of RBM3, also increased after mild hypothermia pretreatment. Silencing RTN3 weakened the protective effect of mild hypothermia pretreatment or RBM3 overexpression. Also, the protein level of autophagy gene LC3B increased after OGD/R or RBM3 overexpression while silencing RTN3 decreased this trend. Furthermore, immunofluorescence observed enhanced fluorescence signal of LC3B and RTN3 as well as a large number of overlaps after RBM3 overexpressing. In conclusion, RBM3 plays a cellular protective role by regulating apoptosis and viability via its downstream gene RTN3 in the hypothermia OGD/R cell model and autophagy may participate in it.
轻度低温在临床实践中被证明具有神经保护作用。虽然低温会导致全身蛋白质合成率降低，但它会上调包括 RNA 结合基序蛋白 3（RBM3）在内的一小部分蛋白质。在这项研究中，我们在氧葡萄糖剥夺/再灌注（OGD/R）前用轻度低温处理小鼠神经母细胞瘤细胞（N2a），发现细胞凋亡率降低，凋亡相关蛋白下调，细胞活力增强。通过质粒过表达 RBM3 会产生类似的效果，而用 siRNAs 沉默 RBM3 则部分逆转了轻度低温预处理的保护作用。RBM3 的下游基因 RTN3 的蛋白水平在轻度低温预处理后也增加。沉默 RTN3 减弱了轻度低温预处理或 RBM3 过表达的保护作用。此外，OGD/R 或 RBM3 过表达后自噬基因 LC3B 的蛋白水平增加，而沉默 RTN3 则降低了这种趋势。此外，免疫荧光观察到 RBM3 过表达后 LC3B 和 RTN3 的荧光信号增强，并且大量重叠。总之，RBM3 通过其下游基因 RTN3 在低温 OGD/R 细胞模型中调节细胞凋亡和活力，发挥细胞保护作用，自噬可能参与其中。
