MiR-702-3p inhibits the inflammatory injury in septic H9c2 cells by regulating NOD1

Abstract

Background: Cardiac insufficiency is a common complication of sepsis and septic shock and is the most common cause of death in critically ill patients. Recent studies have found that microRNAs (miRNAs) play a potential role in sepsis as markers, but little is known about their functional effects on sepsis-induced cardiomyopathy (SIC).

Objective: This study is designed to explore the possible role and underlying mechanisms of miR-702-3p in septic cardiomyopathy.

Methods: As expected, H9c2 cells were induced with lipopolysaccharide (LPS) to construct the model of septic cardiomyopathy. The expression of miR-702-3p was detected by qRT-PCR assay and those of IL-1β, IL-6 and TNF-α by ELISA assay. The viability, proliferation and apoptosis of LPS-treated H9c2 cells were determined by CCK-8, EdU, flow cytometry and western blot assays. Moreover, Nucleotide-binding oligomerization domain-containing protein 1 (NOD1) was predicted and confirmed as a direct target of miR-702-3p by TargetScan, miRwalk and miRDB prediction and dual-luciferase reporter gene assays.

Results: While LPS can weaken the viability of H9c2 cells, miR-702-3p enhances that of LPS-treated H9c2 cells by inhibit the expressions of TNF-α, IL-6, IL-1β. We found NOD1 is a target gene of miR-702-3p, and over-expression of NOD1 restores the inhibitory effects of miR-702-3p on the LPS-treated H9c2 cells.

Conclusion: MiR-702-3p played an important role in the pathogenesis of sepsis cardiomyopathy via targeting NOD1, suggesting that miR-702-3p may be a potential new target for the treatment of SIC.

Keywords: Cardiac insufficiency; Inflammatory injury; NOD1; Sepsis; miRNA-702-3p.