Zhifeng Chen,1– 4 Yulin Shang,5 Yanru Ou,1– 4 Li Zhou,1– 4 Ting Liu,1– 4 Subo Gong,6 Xudong Xiang,7 Yating Peng,1– 4 Ruoyun Ouyang1– 4 

1Department of Pulmonary and Critical Care Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, People’s Republic of China; 2Research Unit of Respiratory Disease, Central South University, Changsha, Hunan, 410011, People’s Republic of China; 3Clinical Medical Research Center for Pulmonary and Critical Care Medicine in Hunan Province, Changsha, Hunan, 410011, People’s Republic of China; 4Diagnosis and Treatment Center of Respiratory Disease, Central South University, Changsha, Hunan, 410011, People’s Republic of China; 5Ophthalmology and Otorhinolaryngology, Zigui Country Hospital of Traditional Chinese Medicine, Yichang, Hubei, 443600, People’s Republic of China; 6Department of Geriatrics, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, People’s Republic of China; 7Department of Emergency, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, People’s Republic of China

Correspondence: Yating Peng; Ruoyun Ouyang, Department of Pulmonary and Critical Care Medicine, The Second Xiangya Hospital, Central South University 139 Middle Renmin Road, Changsha, Hunan, 410011, People’s Republic of China, Email pengyating2011@csu.edu.cn; ouyangruoyun@csu.edu.cn

Background: OSA can cause cognitive impairment (CI). The aim of this study was to investigate whether miR-20a-5p in exosomes derived from bEnd3 cells with IH mediates intercellular crosstalk and induces CI through hippocampal neuronal cell pyroptosis.
Materials and Methods: BEnd3-derived exosomes were isolated from the normal oxygen control group (NC-EXOS) and IH group (IH-EXOS). In vitro, exosomes were cocultured with HT22 cells. Meanwhile, in vivo, exosomes were injected into mice via the caudal vein. The spatial memory ability of mice was tested by MWM method to evaluate the effect of exosomes on the cognitive function of mice. Adults diagnosed with OSA underwent the MoCA and ESS tests to assess cognitive function and daytime sleepiness. Spearman’s rank correlation analysis was used to evaluate the correlation between miR-20a-5p and candidate proteins and clinical parameters. Transfection using small interfering RNAs, miRNA mimics, and plasmids to evaluate the role of miR-20a-5p and its target genes. Dual luciferase reporter gene assay was used to confirm the binding of miR-20a-5p to its target gene.
Results: IH could cause pyroptosis and inflammation in bEnd3 cells, and promote the expression of miR-20a-5p. Isolated IH-EXOS induced increased pyroptosis and activation of inflammatory response in vitro and in vivo, accompanied by increased expression of miR-20a-5p. In addition, IH-EXOS led to decreased learning and memory ability in mice. Interestingly, AHI was higher and MoCA scores were lower in severe OSA compared to healthy comparisons. In addition, miR-20a-5p and GSDMD were positively correlated with AHI but negatively correlated with MoCA in severe OSA. IH-induced exosomes were rich in miR-20a-5p, and these exosomes were found to deliver miR-20a-5p to HT22 cells, playing a key role in the induction of OSA-CI by directly targeting MFN2.
Conclusion: Exosome miR-20a-5p from IH-stimulated bEnd3 cells can promote OSA-CI by increasing HT22 cells pyroptosis through its target MFN2.

Keywords: exosome, OSA, cognitive impairment, miR-20a-5p, MFN2, GSDMD