miR-16-5p Regulates Ferroptosis by Targeting SLC7A11 in Adriamycin-Induced Ferroptosis in Cardiomyocytes.

Introduction: Adriamycin (ADR) is commonly used in tumor chemotherapy, but its nonreversible cardiotoxicity severely hampers its clinical application. Ferroptosis is an implicated cause of ADR-induced injury. However, the underlying molecular mechanisms remain poorly understood. This study explored whether ferroptosis is a pivotal pathogenic pathway underlying ADR-induced cardiotoxicity and the possible molecular mechanisms involved. Methods: In vivo and in vitro experimental models were used to study the mechanism of ADR-mediated ferroptosis. Ferroptosis levels were examined in mice and human/rat cardiomyocytes. Mechanistically, the expression levels of SLC7A11 and related miRNAs were examined. Bioinformatics prediction and luciferase reporter assays were used to verify the potential interaction between miR-16-5p and SLC7A11. The biological functions and interaction of SLC7A11 and miR-16-5p were investigated in vivo and in vitro. Results: Our study observed that ADR treatment significantly increased ferroptosis levels in vivo and in vitro. Ferroptosis-related pharmacological interventions further confirmed these results. Our data displayed that the SLC7A11 level was significantly decreased in cardiac tissues and cells, while an increased expression level of miR-16-5p was observed. Moreover, upregulation of SLC7A1 and inhibition of miR-16-5p attenuated ADR-induced cardiomyocyte ferroptosis injury. Interactive rescue experiments showed that the protective effects of miR-16-5p inhibition on ADR-induced cardiomyocyte injury were blocked by SLC7A11 knockdown. Discussion: Based on these findings, targeting miR-16-5p could partially reverse the ADR-induced cardiotoxicity by rescuing the SLC7A11 to attenuate ferroptosis. This study presents a pre-clinical basis to identify miR-16-5p/SLC7A11 as a potential treatment target for ADR-induced cardiotoxicity.