The alleviating effects of endothelial progenitor cells-derived exosomes on hyperoxia-induced injury of type Ⅱ alveolar epithelial cells in neonatal rats / 中国新生儿科杂志

ABSTRACT

Objective:To study the effects of endothelial progenitor cells (EPC)-derived exosomes on hyperoxia-induced injury in type Ⅱ alveolar epithelial cell (AECⅡ) in neonatal rats.Methods:EPCs of rats were cultured and exosomes were collected using Total Exosome Isolation kit. Primary cultured AECⅡof neonatal rats were randomly assigned into three groups: the control group, the hyperoxia group and the exosome group. The control group was cultured in room air with 5%CO 2, the hyperoxia group was cultured in 95%O 2 with 5%CO 2 and the exosome group was cultured with 0.1 mg/ml EPC-derived exosomes in 95%O 2 with 5%CO 2. Cell viability was detected using cell counting kit-8 (CCK-8) and apoptosis was detected using flow cytometry on d2, d4, and d6. Results:EPC-derived exosomes isolated from EPC culture supernatant were confirmed morphologically using transmission electron microscopy. After co-incubation of Dil-labeled EPC-derived exosomes with AEC Ⅱ for 24 h, Dil fluorescence was detected in the cytoplasm of AEC Ⅱ, indicating exosomes were uptaken by AEC Ⅱ. Compared with the control group, hyperoxia decreased cell viability and increased apoptosis of AEC Ⅱ and the injury was aggravated with the prolongation of hyperoxia duration ( P<0.001). Cell injury in the exosome group was milder than the hyperoxia group ( P<0.001). Compared with the control group, cell viability on d4 and d6 of hyperoxia was lower ( P=0.029 and 0.005 respectively) and cell apoptosis at d6 of hyperoxia was higher in the exosome group ( P=0.007). Conclusions:EPC-derived exosomes may partially attenuate hyperoxia-induced cell injury in neonatal rat AEC Ⅱ.