Sun Li-Qun, Guo Gong-Liang, Zhang Sai, Yang Li-Li
Outpatient Department of Pediatrics, The First Hospital of Jilin University, Changchun, China.
Department of Cardiology, China-Japan Union Hospital of Jilin University, Changchun, China.
Cell Physiol Biochem. 2018;45(2):458-473. doi: 10.1159/000486923. Epub 2018 Jan 24.
BACKGROUND/AIMS: This study aimed to explore the effect of microRNA-592-5p (miR-592-5p) on hypoxic-ischemic brain damage (HIBD)-induced hippocampal neuronal injury in a neonatal mouse model relative to the involvement of one target gene, PTGDR, and the PGD2/ DP signaling pathway.
A total of 30 neonatal mice aged 7 days were randomly selected to establish an HIBD mouse model. Hippocampal neuronal cells were transfected into a control group, a blank group, a negative control (NC) group, an miR-592-5p mimics group, an miR-592-5p inhibitors group, an siRNA-PTGDR group and an miR-592-5p inhibitors + siRNA-PTGDR group. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blot analyses were performed to detect the expression levels of miR-592-5p, PTGDR, DP2, Bcl-2 and Bax in tissues and cells. Cell proliferation, cell cycle and apoptosis were detected by MTT assay and flow cytometry, respectively.
The expression levels of miR-592-5p and Bcl-2 decreased, while the expression levels of PTGDR, DP2 and Bax increased in the HIBD group. PTGDR is a target gene of miR-592-2p. Compared with the NC and blank groups, the expression levels of PTGDR, DP2 and Bax decreased, while the expression levels of miR-592-5p and Bcl-2 increased in the miR-592-5p mimics group. The siRNA-PTGDR group showed the same trend as that observed in the miR-592-5p mimics group, except with no difference in miR-592-5p expression. The miR-592-5p inhibitors group showed an opposite gene expression trend compared to that in the miR-592-5p mimics group. The S phase of the cell cycle was prolonged, the G1 phase was reduced, proliferation was increased, and the apoptosis rate was decreased in the siRNA-PTGDR and miR-592-5p mimics groups. Opposite trends for cell cycle, proliferation and apoptosis were observed in the miR-592-5p inhibitors group.
Our study suggests that miR-592-5p upregulation protects against hippocampal neuronal injury caused by HIBD by targeting PTGDR and inhibiting the PGD2/DP signaling pathway.
背景/目的：本研究旨在探讨相对于一个靶基因前列腺素D2受体（PTGDR）及前列腺素D2/DP信号通路的参与，微小RNA-592-5p（miR-592-5p）对新生小鼠模型中缺氧缺血性脑损伤（HIBD）诱导的海马神经元损伤的影响。
随机选取30只7日龄新生小鼠建立HIBD小鼠模型。将海马神经元细胞转染至对照组、空白组、阴性对照组（NC）、miR-592-5p模拟物组、miR-592-5p抑制剂组、siRNA-PTGDR组及miR-592-5p抑制剂+siRNA-PTGDR组。采用逆转录定量聚合酶链反应（RT-qPCR）和蛋白质免疫印迹分析检测组织和细胞中miR-592-5p、PTGDR、DP2、Bcl-2和Bax的表达水平。分别通过MTT法和流式细胞术检测细胞增殖、细胞周期和细胞凋亡。
HIBD组中miR-592-5p和Bcl-2的表达水平降低，而PTGDR、DP2和Bax的表达水平升高。PTGDR是miR-592-2p的靶基因。与NC组和空白组相比，miR-592-5p模拟物组中PTGDR、DP2和Bax的表达水平降低，而miR-592-5p和Bcl-2的表达水平升高。siRNA-PTGDR组呈现出与miR-592-5p模拟物组相同的趋势，只是miR-592-5p表达无差异。miR-592-5p抑制剂组呈现出与miR-592-5p模拟物组相反的基因表达趋势。siRNA-PTGDR组和miR-592-5p模拟物组的细胞周期S期延长，G1期缩短，增殖增加，凋亡率降低。miR-592-5p抑制剂组在细胞周期、增殖和凋亡方面呈现相反趋势。
我们的研究表明，上调miR-592-5p可通过靶向PTGDR并抑制PGD2/DP信号通路来保护HIBD所致的海马神经元损伤。
