LncRNA XIST knockdown alleviates LPS-induced acute lung injury by inactivation of XIST/miR-132-3p/MAPK14 pathway

Abstract

Acute lung injury (ALI) is a fatal inflammatory response syndrome. LncRNA XIST (XIST) is a lung cancer-related gene and participates in pneumonia. However, whether XIST participates in lipopolysaccharides (LPS)-induced ALI remains unclear. LPS-induced inflammation model was constructed in vitro, then cell viability, cytokines, cell apoptosis, protein, and mRNA expressions were individually detected by cell counting kit-8, enzyme-linked immunosorbent assay and flow cytometry, Western blot, and qRT-PCR. A dual-luciferase reporter assay confirmed the relationships among XIST, miR-132-3p, and MAPK14. Furthermore, inflammation and conditions after knockdown of XIST were assessed by hematoxylin and eosin staining, lung wet-to-dry weight ratio, PaO 2 /FiO 2 ratio, and malondialdehyde (MDA) contents using LPS-induced in vivo model. Our findings indicated that the LPS challenge decreased cell viability, increased cell apoptosis, and caused secretions of pro-inflammatory cytokines. Noticeably, LPS significantly upregulated XIST, MAPK14, and downregulated miR-132-3p. Mechanistically, XIST acted as a molecular sponge to suppress miR-132-3p, and MAPK14 was identified as a target of miR-132-3p. Functional analyses demonstrated that XIST silencing remarkably increased cell survival and alleviated cell death and lung injury through decreasing TNF-α, IL-1β, IL-6, accumulation of inflammatory cells, alveolar hemorrhage, MDA release, and increased PaO 2 /FiO 2 ratio, as well as upregulating Bcl-2, and downregulating Bax, MAPK14, and p-extracellular signal-regulated kinases ½. In contrast, inhibition of the miR-132-3p antagonized the effects of XIST silencing. In conclusion, inhibition of XIST exhibited a protective role in LPS-induced ALI through modulating the miR-132-3p/MAPK14 axis.

Network Pharmacology and Experimental Validation to Explore the Mechanism of Qing-Jin-Hua-Tan-Decoction Against Acute Lung Injury

“…Based on the network pharmacology results, the key targets with higher degree values of the compound-target-pathway network included MAPK14, CDK2, EGFR, F2, SRC, AKT1, and so on. The p38 MAPKs signaling pathway plays an important role in regulating neutrophil activation, especially endotoxin stimulation (Li et al, 2021). In addition, it was demonstrated that MAPK14 was highly expressed in the tissues of ALI mice, and silencing MAPK14 could alleviate ALI symptoms by downregulating inflammatory cytokines (Pan et al, 2019).…”

Nicotinamide mononucleotide alleviates endotoxin-induced acute lung injury by modulating macrophage polarization via the SIRT1/NF-κB pathway

“…Semiquantitative evaluation (lung injury score) of ALI was based on inflammatory cell infiltration, interstitium widening, oedema, and haemorrhage (Li et al. 2021 ; Shi et al. 2021 ).…”

“… 2017 ; Li et al. 2021 ). During acute lung injury, macrophages can be activated by various milieu, and the phenotypes exhibit high plasticity to differentiate into classically activated macrophages (M1) and alternatively activated macrophages (M2) (Vladimirovna et al.…”

Role of Long Noncoding RNAs in the Regulation of Cellular Immune Response and Inflammatory Diseases

“…Zhang et al [ 81 ] found that knockdown of lncRNA XIST inhibited the expression of TLR4 by targeting miR-370-3p, thereby regulating the JAK/STAT3 and NF-κB signaling pathways, inhibiting cellular apoptosis and the secretion level of inflammatory cytokines, and reducing LPS-induced cell damage; this process may be used to develop a strategy for treating acute pneumonia ( Figure 6 ). Li et al [ 82 ] showed that knockdown of lncRNA XIST alleviated cell death and LPS-induced lung injury by regulating the miR-132-3p/MAPK14 pathway ( Figure 6 ).…”