Effects of dexmedetomidine on the expression profile of tsRNAs in LPS‐induced acute lung injury

BACKGROUND: Acute lung injury (ALI) is characterized by impaired alveolar function and excessive inflammation, which is commonly seen in clinical anesthesia and intensive care units. tRNA‐derived small RNA (tsRNA) is a non‐coding RNA that can be used as a potential disease diagnostic biomarker. The connection between ALI and tsRNA remains unknown. We aimed to explore the possible regulatory functions and mechanisms of tsRNAs in ALI treated with DEX. METHODS: Firstly, we established the ALI model by LPS injection and explored the effect of dexmedetomidine (DEX) treatment on lung damage. Then, the lung tissues were obtained from the LPS and LPS + DEX group for small RNA sequencing. RESULTS: We proved that DEX could ameliorate pulmonary injury, and decreased inflammation, pulmonary edema, and ferroptosis (MDA down‐regulation and GPX4 up‐regulation) in ALI. Furthermore, in the tsRNA expression profile, the top 10 down‐regulated tsRNAs were tsRNA‐1018, tsRNA‐3045b, tsRNA‐5021a, tsRNA‐1020, tsRNA‐5002b, tsRNA‐3045b, tsRNA‐1026, tsRNA‐5004a, tsRNA‐5005b and tsRNA‐1009, and the top 10 up‐regulated tsRNAs were tsRNA‐3025b, tsRNA‐3025a, tsRNA‐5016b, tsRNA‐3042b, tsRNA‐3029b, tsRNA‐3028b, tsRNA‐5006a, tsRNA‐3027b, tsRNA‐3027a, and tsRNA‐5009b. The enrichment analysis of GO terms and KEGG pathways pointed that target genes of DE‐tsRNAs were mainly enriched in regulation of transcription‐associated GO terms, NF‐kappa B signaling pathway, MAPK signaling pathway, and PI3K‐Akt signaling pathway. The RT‐qPCR results of tsRNA‐1020 and tsRNA‐1018 were in accordance with small RNA sequencing data. CONCLUSION: DEX affected the abnormal expression of tsRNAs in ALI. These aberrantly expressed tsRNAs and enriched physiological processes provide a scientific basis for the diagnosis and treatment of ALI.