FIN56-induced ferroptosis suppresses the development of endometriosis by augmenting mitochondrial ROS and lipid...

Endometriosis (EMs) is one of the most common gynecologic diseases, and the roles of ferroptosis in EMs have not been fully clarified. The induction of ferroptosis has been demonstrated to inhibit the growth of ectopic lesions in EMs. Although acetyl-CoA carboxylase 1 (ACC1), the rate-limiting enzyme for fatty acid biosynthesis, has been shown to regulate ferroptosis, the detailed mechanism involved has not been fully elucidated. In addition, the role of ACC1, encoded by ACACA, in EMs remains unclear. Thus, the present study aimed to explore the role of ACC1 in ferroptosis and the potential therapeutic effect of the ferroptosis inducer the ferroptosis inducer 56 (FIN56) in EMs.

The effects of ACACA, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 4 (NOX4), and p38 mitogen-activated protein kinase (MAPK) on FIN56-induced ferroptosis were analyzed in ectopic endometrial stromal cells (ecESCs) through Cell Counting Kit-8 (CCK-8) assays, lipid reactive oxygen species (ROS) assays using flow cytometry, lipid peroxidation malondialdehyde (MDA) assays, and transmission electron microscopy (TEM). RNA sequencing (RNA-seq) and Venn diagram analysis were used to explore the possible ACACA-related genes. Drug inhibitor administration, plasmid overexpression, and small interfering RNA (siRNA) knockdown were used to investigate the role of ACACA and NOX4 in ferroptosis. Immunofluorescence analysis and chromatin immunoprecipitation (ChIP) analysis were subsequently conducted to assess the interaction between AT-rich interaction domain 5A (ARID5A) and NOX4. The effects of ACACA and NOX4 on mitochondrial function were assessed via mitochondrial membrane potential (MMP) analysis, mitochondrial ROS (mtROS) production analysis, and adenosine triphosphate (ATP) assays. Ferro orange staining was used to determine the intracellular levels of iron. An EMs mouse model was generated to evaluate the therapeutic effect of FIN56 in vivo.

FIN56 increased intracellular iron levels, lipid peroxidation, and mitochondrial damage, which further triggered ferroptosis in ecESCs. ACACA expression was significantly decreased in ecESCs and ectopic endometrial tissues. Treatment with 5-(tetradecyloxy)-2-furoic acid (TOFA), an allosteric inhibitor of ACC1, alleviated ferroptosis induced by FIN56 in ecESCs. Mechanistically, FIN56 treatment resulted in upregulation of NOX4 expression in ecESCs via activation of the p38 MAPK/ARID5A signaling pathway, which was alleviated by ACACA inhibition. Additionally, ACACA and NOX4 increase ferroptosis-dependent cytotoxicity by impairing mitochondrial function and oxidative stress-induced lipid peroxidation in ecESCs. Finally, the regression of ectopic lesions after FIN56 administration was verified in an EMs mouse model.

The findings reveal that ACACA deficiency protected ecESCs from ferroptosis-dependent cytotoxicity through the p38 MAPK/ARID5A/NOX4 pathway. Moreover, ferroptosis induction by FIN56 in the EMs model mice alleviated the disease. Thus, the ferroptosis inducer FIN56 may be a new therapeutic for EMs.