ACSL4 Regulates LPS-Induced Ferroptosis in Cardiomyocytes through FASN.

Objective: Myocardial injury is a prevalent complication of sepsis. This study aims to shed light on the role of Acyl-CoA Synthetase Long Chain Family Member 4 (ACSL4) in regulating Fatty Acid Synthase (FASN) to identify the intrinsic molecular mechanisms of sepsis-induced myocardial injury.

Method: H9c2 cells were treated with Lipopolysaccharide (LPS) to model sepsis-induced cardiomyocyte injury and were subsequently divided into seven groups: Control, LPS, LPS+sh-NC, LPS+sh-ACSL4, LPS+sh-ACSL4+Erastin, LPS+sh-ACSL4+oe-NC, and LPS+sh-ACSL4+oe-FASN. Immunofluorescence staining and Western blot analysis were used to assess the expression levels of ACSL4, FASN, GPX4, and FTH1. Co-immunoprecipitation was conducted to investigate the interaction between ACSL4 and FASN. Additionally, levels of LDH, MDA, GSH, SOD, and iron were measured. We employed the CCK-8 assay and flow cytometry to determine cell viability and apoptosis rates.

Result: Compared with the control group, the LPS group showed decreased cell viability, increased apoptosis rate, elevated levels of LDH, MDA, and iron, reduced GSH and SOD levels, upregulated ACSL4 and FASN expression, and downregulated GPX4 and FTH1 expression. Treatment with sh-ACSL4 helped to ameliorate these changes. In the LPS+sh-ACSL4+Erastin group, cell viability declined further, apoptosis rate increased, and LDH, MDA, and iron levels were elevated, while GSH and SOD levels decreased, and GPX4 and FTH1 expression were reduced compared with the LPS+sh-ACSL4 group. Co-immunoprecipitation revealed an interaction between ACSL4 and FASN. Knockdown of ACSL4 combined with FASN overexpression attenuated the protective influence of ACSL4 knockdown on H9c2 cells.

Conclusion: ACSL4 may play an important role in LPS-induced cardiomyocyte injury by influencing the process of ferroptosis via FASN.