Department of Neurosurgery, General Hospital of Ningxia Medical University, Yinchuan, Ningxia 750004, P.R. China.
Department of Hospital Infection Management, Zhongning County People's Hospital, Zhongwei, Ningxia 751200, P.R. China.
Int J Mol Med. 2022 Aug;50(2). doi: 10.3892/ijmm.2022.5165. Epub 2022 Jun 28.
Cerebral ischemia‑reperfusion injury (CIRI) is associated with high morbidity and mortality rates and its pathogenesis is complex. Phosphodiesterase 2 (PDE2) has been proposed to exert a protective effect, although, to the to the best of the authors' knowledge, its role in CIRI has yet to be reported. Therefore, the aim of the present study was to investigate the role of PDE2 in CIRI. To meet this aim, a middle cerebral artery occlusion (MCAO) model was established in mice. After having successfully modeled the MCAO, the mice were treated with the PDE2 inhibitor Bay‑607550 and the expression level of PDE2 was detected using reverse transcription‑quantitative (RT‑q) PCR and western blot analysis. Histopathology of the brain was assessed using hematoxylin and eosin staining. The proportions of dry and wet tissue in brain were recorded and the cerebral ischemia area was assessed using 2,3,5‑triphenyltetrazolium chloride staining. RT‑qPCR was also used to measure the expression levels of inflammatory factors. The expression of ionized calcium binding adaptor molecule 1, a marker of microglia activation, was detected by immunofluorescence assay, western blotting and RT‑qPCR. Western blotting was used to detect the expression levels of P65 and NF‑κB inhibitor α and their phosphorylated forms. The levels of apoptosis were subsequently determined using TUNEL and western blot analysis. SH‑SY5Y cells were induced by oxygen‑glucose deprivation (OGD) and the expression levels of PDE2 were subsequently detected. Cell transfection was used to interfere with the expression of PDE2 and the regulation of PDE2 upon OGD/reoxygenation (OGD/R)‑induced inflammation and apoptosis was further detected in cell experiments. Finally, western blot analysis was used to detect the expression of protein kinase A (PKA) downstream of PDE2 and . The expression levels of PDE2 were found to be significantly increased in the MCAO model mice. Following treatment with Bay‑607550, the condition of the brain nerve cells was improved with respect to the levels of cerebral ischemia, inflammation and apoptosis. The results of the cell experiments were found to be consistent with those of the animal experiments. Furthermore, the western blotting experiments suggested that the above‑mentioned regulation of PDE2 may be achieved via regulating PKA. Taken together, the present study has shown that inhibition of PDE2 led to a reduction in inflammation and apoptosis during CIRI through regulating PKA.
脑缺血再灌注损伤（CIRI）与高发病率和死亡率相关，其发病机制复杂。磷酸二酯酶 2（PDE2）已被提出发挥保护作用，尽管据作者所知，其在 CIRI 中的作用尚未见报道。因此，本研究旨在探讨 PDE2 在 CIRI 中的作用。为了达到这一目的，建立了小鼠大脑中动脉闭塞（MCAO）模型。在成功建立 MCAO 模型后，用 PDE2 抑制剂 Bay-607550 处理小鼠，并通过逆转录-定量（RT-q）PCR 和 Western blot 分析检测 PDE2 的表达水平。使用苏木精和伊红染色评估脑的组织病理学。记录脑组织的干重和湿重比例，并使用 2,3,5-三苯基氯化四唑染色评估脑缺血面积。还使用 RT-qPCR 测量炎症因子的表达水平。通过免疫荧光染色、Western blot 和 RT-qPCR 检测离子钙结合接头分子 1 的表达，该分子是小胶质细胞激活的标志物。Western blot 用于检测 P65 和 NF-κB 抑制剂 α 及其磷酸化形式的表达水平。随后使用 TUNEL 和 Western blot 分析测定细胞凋亡水平。用氧葡萄糖剥夺（OGD）诱导 SH-SY5Y 细胞，随后检测 PDE2 的表达。细胞转染用于干扰 PDE2 的表达，并在细胞实验中进一步检测 PDE2 对 OGD/复氧（OGD/R）诱导的炎症和细胞凋亡的调节作用。最后，Western blot 分析用于检测 PDE2 下游蛋白激酶 A（PKA）的表达。在 MCAO 模型小鼠中发现 PDE2 的表达水平明显增加。用 Bay-607550 处理后，大脑神经细胞的状况得到改善，脑缺血、炎症和细胞凋亡的水平降低。动物实验的结果与细胞实验的结果一致。此外，Western blot 实验表明，上述 PDE2 的调节可能是通过调节 PKA 实现的。综上所述，本研究表明，通过调节 PKA，抑制 PDE2 可减少 CIRI 过程中的炎症和细胞凋亡。
