Deep Illumina sequencing reveals differential expression of long non-coding RNAs in hyperoxia induced bronchopulmonary dysplasia in a rat model.

BACKGROUND

Bronchopulmonary dysplasia (BPD) in premature infants is a predominantly secondary occurrence to intrauterine inflammation/infection and postpartum mechanical ventilation; The purpose of this study is to explore the biological roles of lincRNA in the pathogenesis of BPD.

METHODS

Newborn rats were randomly assigned to hyperoxia (85% O) or the control group: the normoxia group (21% O). Lung tissues were collected on days 1-14. The BPD animal model was validated using HE staining, Masson staining, and real-time RT-PCR. Deep Illumina sequencing was used to reveal the differential expression of long non-coding RNAs in hyperoxia bronchopulmonary dysplasia rat models. KEGG and GO functions were predicted. Nine possible BPD-related target lincRNAs were verified by RTq-PCR.

RESULTS

The histopathologic changes in lung tissues manifested as hyperaemia, edema, hemorrhage, and inflammation cell infiltration after continuous exposure to hyperoxia for 3 days, and became aggravated after 7 days of hyperoxic exposure. The above lung tissue inflammatory manifestations were alleviated and taken over by pulmonary interstitia hyperplasia and fibrocyte proliferation after 14 days of hyperoxic exposure. The expressions of lincRNA differed between the hyperoxia bronchopulmonary dysplasia model group and the normoxia group. 1175 different lincRNAs were detected in the hyperoxia group and the normoxia group, of which 544 were up-regulated and 631 were down-regulated. 673 moleculars related to GO functions were enriched, including cell location and biological process. Pathway enrichment analysis showed that lincRNA was involved in 257 KEGG pathways. 9 lincRNA were validated in the sample, and the difference was statistically significant.

CONCLUSION

LincRNAs were identified differently between the BPD model and the normoxia group. Many target genes were involved in the developmental process, including cell component biogenesis, biological regulation, transcription regulator, and translation regulator. The BPD might be caused by the activation of the pathways of the EMC-receptor interaction, cytokine-cytokine receptor interaction, cell cycle, and cell adhesion molecules. The present study provides new insight into the pathogenesis mechanism of BPD.