Obstetrics and Gynecology Department, the Affiliated Changzhou No. 2 People's Hospital of Nanjing Medical University, No. 188 Gehu Lake Road, Wujin District, Changzhou, Jiangsu, China.
Department of Orthopedics, The First Affiliated Hospital of Xiamen University, Xiamen, China.
Cell Commun Signal. 2020 Feb 26;18(1):32. doi: 10.1186/s12964-020-0526-0.
Mimicking ischemia-reperfusion injury, oxygen and glucose deprivation (OGD)-re-oxygenation (OGDR) applied to endometrial cells produces significant oxidative stress and programmed necrosis, which can be inhibited by nuclear-factor-E2-related factor 2 (Nrf2) signaling. MicroRNA (miRNA)-induced repression of Keap1, a Nrf2 suppressor protein that facilitates Nrf2 degradation, is novel strategy to activate Nrf2 cascade.
MicroRNA-941 (miR-941) was exogenously expressed in HESC and primary human endometrial cells, and the Nrf2 pathway examined by Western blotting and real-time quantitative PCR analysis. The endometrial cells were treated with OGDR, cell programmed necrosis and apoptosis were tested.
MiR-941 is a novel Keap1-targeting miRNA that regulates Nrf2 activity. In T-HESC cells and primary human endometrial cells, ectopic overexpression of miR-941 suppressed Keap1 3'-UTR (untranslated region) expression and downregulated its mRNA/protein expression, leading to activation of the Nrf2 cascade. Conversely, inhibition of miR-941 elevated Keap1 expression and activity in endometrial cells, resulting in suppression of Nrf2 activation. MiR-941 overexpression in endometrial cells attenuated OGDR-induced oxidative stress and programmed necrosis, whereas miR-941 inhibition enhanced oxidative stress and programmed necrosis. MiR-941 overexpression and inhibition were completely ineffective in Keap1-/Nrf2-KO T-HESC cells (using CRISPR/Cas9 strategy). Restoring Keap1 expression, using an UTR-depleted Keap1 construct, abolished miR-941-induced anti-OGDR activity in T-HESC cells. Thus Keap1-Nrf2 cascade activation is required for miR-941-induced endometrial cell protection.
Targeting Keap1 by miR-941 activates Nrf2 cascade to protect human endometrial cells from OGDR-induced oxidative stress and programmed necrosis. Video Abstract.
模拟缺血再灌注损伤，氧和葡萄糖剥夺（OGD）-复氧（OGDR）应用于子宫内膜细胞会产生显著的氧化应激和程序性细胞坏死，这可以被核因子-E2 相关因子 2（Nrf2）信号所抑制。微 RNA（miRNA）诱导 Keap1 的抑制，Keap1 是一种 Nrf2 抑制蛋白，促进 Nrf2 降解，是激活 Nrf2 级联反应的新策略。
外源性表达 miRNA-941（miR-941）于 HESC 和原代人子宫内膜细胞中，并通过 Western blot 和实时定量 PCR 分析检测 Nrf2 途径。用 OGDR 处理子宫内膜细胞，检测细胞程序性坏死和凋亡。
miR-941 是一种新型的 Keap1 靶向 miRNA，调节 Nrf2 活性。在 T-HESC 细胞和原代人子宫内膜细胞中，外源性过表达 miR-941 抑制 Keap1 3'UTR（非翻译区）表达，并下调其 mRNA/蛋白表达，导致 Nrf2 级联的激活。相反，抑制 miR-941 会增加子宫内膜细胞中 Keap1 的表达和活性，从而抑制 Nrf2 的激活。miR-941 在子宫内膜细胞中的过表达可减轻 OGDR 诱导的氧化应激和程序性坏死，而 miR-941 的抑制则增强了氧化应激和程序性坏死。在 Keap1-/Nrf2-KO T-HESC 细胞（使用 CRISPR/Cas9 策略）中，miR-941 的过表达和抑制都是完全无效的。使用 UTR 缺失的 Keap1 构建体恢复 Keap1 表达，可消除 miR-941 在 T-HESC 细胞中对 OGDR 诱导的抗活性。因此，Keap1-Nrf2 级联激活是 miR-941 诱导的子宫内膜细胞保护所必需的。
miR-941 通过靶向 Keap1 激活 Nrf2 级联反应，保护人子宫内膜细胞免受 OGDR 诱导的氧化应激和程序性细胞坏死。
