Protective effects of P2X7 R antagonist in sepsis-induced acute lung injury in mice via regulation of circ_0001679 and circ_0001212 and downstream Pln, Cdh2, and Nprl3 expression.

Zou, Zijun; Wang, Qin; Zhou, Minggen; Li, Weichao; Zheng, Yikai; Li, Fanyi; Zheng, Shengcai; He, Zhijie

BACKGROUND Sepsis induces pulmonary P2X7 receptor (P2X7 R) expression, and P2X7 R-knockout reduced lung inflammation in mice. This study investigated expression of circular RNA (circRNA) and messenger RNA (mRNA) in sepsis-induced acute lung injury (ALI) treated with a P2X7 R antagonist. METHODS Sepsis was induced by tracheal administration of lipopolysaccharide (LPS), and the mice were then divided into two groups: without (sepsis + DMSO) or with P2X7 R antagonist treatment (sepsis + P2X7 A). Sham mice was administrated sterile normal saline. Serum levels of interleukin 1β (IL-1β) and tumor necrosis factor-α (TNF-α), pathological changes, cell apoptosis, and P2X7 R expression in lung were assessed, following with RNA-seq and bioinformatics analyses. RT-qPCR was used to validate circRNAs and mRNAs RESULTS: Compared with sham group, LPS-induced sepsis produced obvious pathological changes in lung tissue, increased apoptotic lung cells, serum TNF-α and IL-1β levels, and P2X7 R expression; P2X7 R antagonism significantly ameliorated these changes. RNA-seq identified many dysregulated circRNAs and mRNAs during sepsis, while changed with P2X7 R antagonism. RT-qPCR confirmed that Mus musculus (mmu)_circ_0001679, mmu_circ_0001212, Pln, Cdh2, and Nprl3 expression were significantly increased in sepsis + DMSO group compared with that in the sham group but were decreased in the sepsis + P2X7 A group compared with that in the sepsis + DMSO group. circRNA-miRNA-mRNA coexpression network indicated that mmu_circ_0001679 may regulate Nprl3 and that mmu_circ_0001212 may similarly regulate Pln, Cdh2, and Nprl3 as a ceRNA. CONCLUSIONS P2X7 R antagonism attenuates sepsis-induced ALI by inhibiting dysregulated expression of circRNA (circ_0001679, circ_0001212) and mRNA (Pln, Cdh2, and Nprl3).