Recent studies have identified that N6-methyladenosine (m6A) extensively participates in the myocardial injury pathophysiological process. However, the role of m6A on sepsis-induced myocardial injury is still unclear. Here, we investigated the functions and mechanism of m6A methyltransferase METTL3 for septic myocardial injury. Results illustrated that the m6A modification level and METTL3 up-regulated in the lipopolysaccharide (LPS)-induced cardiomyocytes (H9C2 cells). Methylated RNA immunoprecipitation sequencing (MeRIP-Seq) revealed the m6A profile of the septic myocardial injury cellular model. Functionally, METTL3 knockdown repressed the inflammatory damage of cardiomyocytes induced by LPS. Mechanistically, we found that HDAC4 had remarkable m6A modification sites on its 3’-UTR genome, acting as the downstream target of METTL3. Besides, m6A reader IGF2BP1 recognized the m6A modification sites on HDAC4 mRNA and enhanced its RNA stability. In conclusion, the findings illustrated a role of METTL3/IGF2BP1/m6A/HDAC4 axis on sepsis-induced myocardial injury, which might provide novel therapeutic strategy for septic myocardial injury.
Purpose. Present study is aimed to explore the role of miR-186-5p in sepsis-induced coagulation disorders and molecular mechanisms. Methods. Thirty-four sepsis patients and 34 respiratory infection/pneumonia patients were selected in the present study. Polymicrobial sepsis model was created by cecal ligation and puncture (CLP). The mRNA expression was detected by qRT-PCR. Western blot was utilized to measure protein expression. Thromborel S Reagent was applied to measure the prothrombin time (PT). Platelet count of blood was measured via LH 780. ELISA kits were utilized to evaluate the fibrinogen and PAI-1 concentration. Results. MiR-186-5p expression was lower and nicotinamide phosphoribosyltransferase (NAMPT) mRNA expression was higher in sepsis patients in contrast to control group. Coagulation time was markedly prolonged and platelet count was markedly decreased in CLP mice. In addition, fibrinogen concentration was obviously lower and PAI-1 concentration was obviously higher in CLP mice. MiR-186-5p mimic obviously decreased coagulation time and PAI-1 concentration, while raised platelet count and fibrinogen concentration. Targetscan predicted miR-186-5p might directly regulates NAMPT, and luciferase reporter assay verified this prediction. In addition, miR-186-5p mimic obviously inhibited the mRNA expression of NAMPT. Knockdown of NAMPT improved coagulation dysfunction in sepsis. Overexpression of NAMPT reversed the improvement effect of miR-186-5p on coagulation dysfunction. MiR-186-5p mimic markedly inhibited NF-κB pathway. Conclusion. MiR-186-5p inhibited sepsis-induced coagulation disorders via targeting NAMPT and inactivating NF-κB pathway.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.