Psychiatric Department, Qingdao Mental Health Center, Qingdao university, Qingdao City, China.
Brain Behav. 2020 Sep;10(9):e01653. doi: 10.1002/brb3.1653. Epub 2020 Jul 30.
BACKGROUND/AIMS: MicroRNA(miR)-345-5p plays a key role in various cellular functions. However, the function of miR-345-5p in resistant depression (TRD) is unclear. The aim of this study was to evaluate the role and mechanism of miR-345-5p in the treatment of resistance depression (TRD).
RT-qPCR was used to detect the expression of miR-345-5p in BV-2 microglia. CCK-8 method and flow cytometry were used for cell viability and apoptosis of microglia. Target gene prediction and screening, and luciferase reporter assays were used to verify the downstream target gene of miR-345-5p. Western blot was used to analyze the protein expression of related proteins.
miR-345-5p increased the cell viability of BV-2 microglia and the expression level of pro-inflammatory cytokines. In addition, the conditioned medium of microglia treated with miR-345-5p reduced the cell viability of HT22 hippocampal cells and caused S-phase arrest. The miR-345-5p-treated microglia induced apoptosis by regulating the expression levels of Bax, Bcl-2, pro-caspase-3, and cleaved caspase-3. Furthermore, SOCS1 was a direct target of miR-345-5p, and overexpression of SOCS1 was able to reverse the proapoptotic effect of miR-345-5p on activation of microglia on hippocampal neurons.
miR-345-5p induced inflammatory damage in hippocampal neurons by activating microglia. MiR-345-5p may be an effective target for TRD therapy.
背景/目的：微小 RNA（miR）-345-5p 在各种细胞功能中发挥关键作用。然而，miR-345-5p 在难治性抑郁症（TRD）中的作用尚不清楚。本研究旨在评估 miR-345-5p 在治疗抵抗性抑郁症（TRD）中的作用和机制。
采用 RT-qPCR 检测 BV-2 小胶质细胞中 miR-345-5p 的表达。CCK-8 法和流式细胞术检测小胶质细胞的活力和凋亡。靶基因预测和筛选以及荧光素酶报告基因检测用于验证 miR-345-5p 的下游靶基因。Western blot 用于分析相关蛋白的表达水平。
miR-345-5p 增加了 BV-2 小胶质细胞的细胞活力和促炎细胞因子的表达水平。此外，用 miR-345-5p 处理的小胶质细胞的条件培养基降低了 HT22 海马细胞的细胞活力并导致 S 期停滞。miR-345-5p 通过调节 Bax、Bcl-2、pro-caspase-3 和 cleaved caspase-3 的表达水平来诱导小胶质细胞凋亡。此外，SOCS1 是 miR-345-5p 的直接靶标，SOCS1 的过表达能够逆转 miR-345-5p 对小胶质细胞激活引起的海马神经元凋亡作用。
miR-345-5p 通过激活小胶质细胞诱导海马神经元的炎症损伤。miR-345-5p 可能是 TRD 治疗的有效靶点。
