The differential expression of novel circular RNAs in an acute lung injury rat model caused by smoke inhalation
Acute lung injury caused by smoke inhalation is a common severe clinical syndrome. This study aimed to investigate the potential expression of circular RNAs during acute lung injury triggered by smoke inhalation. The acute lung injury rat model was established with smoke inhalation from a self-made smoke generator. The occurrence of acute lung injury was validated by an analysis of the bronchoalveolar lavage fluid and hematoxylin-eosin (HE) staining of lung tissues. Next-generation sequencing and quantitative PCR were performed to identify the differentially expressed circular RNAs associated with acute lung injury that was caused by smoke inhalation. The circular form of the identified RNAs was finally verified by multiple RT-PCR-based assays. The bronchoalveolar lavage fluid (BALF) and lung tissue analysis showed that smoke inhalation successfully induced acute injury in rats, as evidenced by the significantly altered cell numbers, including macrophages, neutrophils, and red blood cells, disrupted cell lining, and increased levels of interleukin-1β, tumor necrosis factor-alpha, and IL-8 in lung tissues. Ten significantly differentially expressed circular RNAs were identified with next-generation sequencing and RT-PCR. The circular form of these RNAs was verified by multiple RT-PCR-based assays. In conclusion, the identified circular RNAs were prevalently and differentially expressed in rat lungs after acute lung injury caused by smoke inhalation.
KeywordsAcute lung injury Smoke inhalation Circular RNA Rat model
This study was supported by Science and Technology Plan Projects of Guangdong Province (Nos. 2014A020212533 and 2014A020212707).
Compliance with ethical standards
All experiments were authorized by the Animal Care and Ethics Committee of Sun Yat-sen University.
Conflict of interest
The authors have no conflicts of interest to declare.
- 6.Greene J, Baird AM, Brady L, Lim M, Gray SG, Mcdermott R & Finn SP. (2017). Circular RNAs: biogenesis, function and role in human diseases. Front Mol Biosci. 4:38. https://doi.org/10.3389/fmolb.2017.00038
- 7.Guo Z, Wen Z, Qin A, Zhou Y, Liao Z, Liu Z, Liang Y, Ren T, Xu L (2013) Antisense oligonucleotide treatment enhances the recovery of acute lung injury through IL-10ق€ secreting M2-like macrophage-induced expansion of CD4+ regulatory T cells. J Immunol 190(8):4337–4348. https://doi.org/10.4049/jimmunol.1203233 CrossRefPubMedPubMedCentralGoogle Scholar
- 15.Sanger HL, Klotz G, Riesner D, Gross HJ, Kleinschmidt AK (1976) Viroids are single-stranded covalently closed circular RNA molecules existing as highly base-paired rod-like structures. Proc Natl Acad Sci U S A 73(11):3852–3856. https://doi.org/10.1073/pnas.73.11.3852 CrossRefPubMedPubMedCentralGoogle Scholar
- 19.Wan L, Zhang L, Fan K, Cheng ZX, Sun QC, Wang JJ Circular RNA-ITCH suppresses lung cancer proliferation via inhibiting the Wnt/خ -catenin pathway. Biomed Res Int 2016, 2016:1–11Google Scholar
- 23.Zhang P, Zuo Z, Shang W, Wu A, Bi R, Wu J, Li S, Sun X, Jiang L (2017) Identification of differentially expressed circular RNAs in human colorectal cancer. Tumour Biol J Int Soc Oncodev Biol Med 39:1010428317694546Google Scholar
- 25.Zhu X, Wang X, Wei S, Chen Y, Chen Y, Fan X, Han S & Wu G. (2017). hsa_circ_0013958: a circular RNA and potential novel biomarker for lung adenocarcinoma. FEBS J 284(14):2170–2182Google Scholar