SP1-induced ZFAS1 aggravates sepsis-induced cardiac dysfunction via miR-590-3p/NLRP3-mediated autophagy and pyroptosis

Background: Sepsis-induced cardiac dysfunction is one of the leading complications of sepsis, contributing to the high morbidity and mortality of septic patients. Several lines of evidence have demonstrated that autophagy and pyroptosis may be involved in septic cardiac dysfunction. In this study, we examined the impact of zinc finger antisense 1 (ZFAS1) on sepsis-induced myocardial dysfunction via regulating pyroptosis and autophagy.

Method: Mice with cecal ligation and puncture (CLP)-induced sepsis was constructed in vivo. Myocardial injury was assessed by H&E staining, immunohistochemistry (IHC) for NLRP3, caspase 1, and interleukin (IL)-1β, as well as ELISA assay for serum levels of creatine kinase (CK), CK-MB, tumor necrosis factor α (TNF-α), and IL-1β. Primary cardiomyocytes exposed to lipopolysaccharide (LPS) were established to simulate sepsis-induced cardiac dysfunction in vitro. Cell viability was examined by MTT assay and concentration of TNF-α and IL-1β was measured by ELISA. Flow cytometry, immunofluorescent staining and western blotting were performed to assess pyroptosis and autophagy. The transcriptional regulation of SP1 on ZFAS1 was determined using ChIP assay. Luciferase reporter assay was performed to verify the ZFAS1/miR-590-3p interaction. Besides, activation of AMPK/mTOR signaling was detected using western blotting.

Results: Highly expressed ZFAS1 was observed in sepsis-induced cardiac dysfunction in the in vivo and in vitro model. Knockdown of ZFAS1 robustly abolished LPS-induced pyroptosis and attenuated the inhibition of autophagy. SP1 was identified to be an essential transcription factor to positively regulate ZFAS1 expression. Moreover, miR-590-3p functioned as a downstream effector to reverse ZFAS1-mediated sepsis-induced cardiac dysfunction. AMPK/mTOR signaling was involved in miR-590-3p-regulated autophagy and pyroptosis of cardiomyocytes. Furthermore, the regulatory network of ZFAS1/miR-590-3p on AMPK/mTOR signaling was verified in vivo.

Conclusion: ZFAS1, activated by SP1, aggravates the progression of sepsis-induced cardiac dysfunction via targeting miR-590-3p/AMPK/mTOR signaling-mediated autophagy and pyroptosis of cardiomyocytes.