Knockdown of LncRNA DLX6-AS1 inhibits HK-2 cell pyroptosis via regulating miR-223-3p/NLRP3 pathway in lipopolysaccharide-induced acute kidney injury

Sepsis-induced acute kidney injury (AKI) represents a severe medical complication. Recently, there is growing evidence indicating the regulatory role of long non-coding RNAs (lncRNAs) in AKI pathophysiology. The present study investigated lncRNA DLX6 antisense RNA 1 (DLX6-AS1) expression in septic AKI patients and to decipher the relevant mechanisms underlying DLX6-AS1-mediated HK-2 cell pyroptosis in lipopolysaccharide (LPS)-induced AKI. The results revealed that DLX6-AS1 was up-regulated in the serum from septic AKI patients. DLX6-AS1 expression were positively associated with the creatinine levels in the serum from the septic AKI patients. In vitro studies showed that LPS induced cytotoxicity and enhanced DLX6-AS1 expression of HK-2 cells; increased NLR family pyrin domain containing 3 (NLRP3), interleukin (IL)-1β and IL-18 expression. DLX6-AS1 overexpression promoted cytotoxicity and pyroptosis of HK-2 cells; while DLX6-AS1 knockdown counteracted the LPS-induced cytotoxicity and pyroptosis of HK-2 cells. More importantly, DLX6-AS1 sponged miR-223-3p resulting in repression of miR-223-3p expression in HK-2 cells. MiR-223-3p could bind to the 3′ untranslated region of NLRP3, which results in the suppressed NLRP3 expression of HK-2 cells. Further rescue experiments showed that enhanced miR-223-3p expression partially reversed the cytotoxicity and pyroptosis of HK-2 cells upon LPS stimulation or with DLX6-AS1 overexpression. Conclusively, this study identified enhanced DLX6-AS1 expression in the serum from AKI patients. Further mechanistic findings deciphered that DLX6-AS1 mediated LPS-mediated cytotoxicity and pyroptosis in HK-2 via miR-223-3p/NLRP3 axis.