The Department of Pediatric, Shenzhen Children's Hospital, China Medical University, Shenzhen, Guangdong, China.
The Department of Pediatric, Longgang District Maternity & Child Healthcare Hospital of Shenzhen City, (Longgang Maternity and Child Institute of Shantou University Medical College), Shenzhen, Guangdong, China.
FASEB J. 2024 Aug 31;38(16):e70012. doi: 10.1096/fj.202400374R.
Mesenchymal stem cells (MSC)-derived exosomes (Exo) are a possible option for hyperoxia-induced lung injury (HLI). We wanted to see if melatonin (MT)-pretreated MSC-derived exosomes (MT-Exo) were more effective against HLI, and we also tried to figure out the underlying mechanism. HLI models were established by hyperoxia exposure. HE staining was adopted to analyze lung pathological changes. MTT and flow cytometry were used to determine cell viability and apoptosis, respectively. The mitochondrial membrane potential (MMP) was analyzed using the JC-1 probe. LDH, ROS, SOD, and GSH-Px levels were examined by the corresponding kits. The interactions between miR-18a-5p, PUM2, and DUB3 were analyzed by molecular interaction experiments. MT-Exo could effectively inhibit hyperoxia-induced oxidative stress, inflammatory injury, and apoptosis in lung epithelial cells, while these effects of MT-Exo were weakened by miR-18a-5p knockdown in MSCs. miR-18a-5p reduced PUM2 expression in MLE-12 cells by directly targeting PUM2. In addition, PUM2 inactivated the Nrf2/HO-1 signaling pathway by promoting DUB3 mRNA decay post-transcriptionally. As expected, PUM2 overexpression or DUB3 knockdown abolished the protective effect of MT-Exo on hyperoxia-induced lung epithelial cell injury. MT-Exo carrying miR-18a-5p reduced hyperoxia-mediated lung injury in mice through activating Nrf2/HO-1 pathway. MT reduced PUM2 expression and subsequently activated the DUB3/Nrf2/HO-1 signal axis by increasing miR-18a-5p expression in MSC-derived exosomes to alleviate HLI.
间充质干细胞（MSC）衍生的外泌体（Exo）是一种治疗高氧诱导肺损伤（HLI）的可能选择。我们想看看褪黑素（MT）预处理的 MSC 衍生的外泌体（MT-Exo）是否对 HLI 更有效，并试图找出其潜在的机制。通过高氧暴露建立 HLI 模型。采用 HE 染色分析肺组织病理学变化。MTT 和流式细胞术分别用于测定细胞活力和凋亡。使用 JC-1 探针分析线粒体膜电位（MMP）。通过相应的试剂盒检测 LDH、ROS、SOD 和 GSH-Px 水平。通过分子相互作用实验分析 miR-18a-5p、PUM2 和 DUB3 之间的相互作用。MT-Exo 可有效抑制高氧诱导的肺上皮细胞氧化应激、炎症损伤和凋亡，而 MSC 中 miR-18a-5p 敲低则削弱了 MT-Exo 的这些作用。miR-18a-5p 通过直接靶向 PUM2 降低 MLE-12 细胞中的 PUM2 表达。此外，PUM2 通过促进 DUB3 mRNA 转录后降解使 Nrf2/HO-1 信号通路失活。不出所料，PUM2 过表达或 DUB3 敲低消除了 MT-Exo 对高氧诱导的肺上皮细胞损伤的保护作用。携带 miR-18a-5p 的 MT-Exo 通过激活 Nrf2/HO-1 通路减轻高氧介导的肺损伤。MT 通过增加 MSC 衍生的外泌体中 miR-18a-5p 的表达来降低 PUM2 表达，从而激活 DUB3/Nrf2/HO-1 信号轴，减轻 HLI，从而降低高氧介导的肺损伤。
