LncRNA MALAT1 Forms a Negative Feedback Loop With lncRNA CRNDE in Sepsis to Regulate Lung Cell Apoptosis

Background: It has been reported that lncRNAs MALAT1 and CRNDE plays opposite roles in sepsis. Therefore, they may have crosstalk. We therefore explored the potential interaction between them in sepsis. Methods: : Plasma samples were collected from both sepsis patients (n=60) and healthy controls (n=60). Expression of MALAT1 and CRNDE in plasma samples before than after treatment was determined by RT-qPCR. Results: : Overexpression of MALAT1 and CRNDE in Human Bronchial Epithelial Cells (HBEpCs) was achieved to explore the relationship between them. The roles of MALAT1 and CRNDE in regulating the apoptosis of HBEpCs were analyzed by cell apoptosis assay. MALAT1 was upregulated in sepsis, while CRNDE was downregulated in sepsis. In lung cells, overexpression of MALAT1 and CRNDE mediated the downregulation of each other. With proper treatment, MALAT1 was downregulated in sepsis and CRNDE was upregulated in sepsis. In lung cells, LPS mediated the upregulation of MALAT1 and the downregulation of CRNDE. Cell apoptosis analysis showed that MALAT1 overexpression promoted the apoptosis of lung cells induced by LPS, and the overexpression of CRNDE played an opposite role. Moreover, CRNDE overexpression attenuated the effects of MALAT1 overexpression. Conclusion: MALAT1 may form a negative feedback loop with CRNDE in sepsis to regulate lung cell apoptosis.