Mechanism of SLC1A5 Regulation of Glutamine Metabolism to Promote Ferroptosis Sensitivity in Endometriosis.

Abstract

Background: Endometriosis (EMs) is a chronic gynecological disorder associated with ectopic endometrial tissue, inflammation, oxidative stress, and mitochondrial dysfunction. A promising strategy for treating EMs is to target ferroptosis, a programmed cell death mechanism regulated by reactive oxygen species (ROS) and glutamine metabolism. Solute carrier family 1 member 5 (SLC1A5), a glutamine transporter, and c-Myc play key roles in ferroptosis, forming a "ROS/c-Myc/SLC1A5" feedback loop. The aim of this study was to investigate the regulatory role of SLC1A5 in ferroptosis. In addition, we evaluated the ferroptosis inducer Erastin as a potential therapeutic agent for EMs.

Methods: The human endometrial stromal cells (ESCs) line hEM15A was used in this study, together with a rat model of EMs. hEM15A cells and rats were treated with Erastin, with or without SLC1A5 modulation or ROS scavenging with N-acetylcysteine (NAC). Cell viability, ROS levels, glutamine metabolism, mitochondrial function, and ferroptosis markers (glutathione peroxidase 4 (GPX4)) were subsequently analyzed by Cell Counting Kit-8 (CCK-8) assay, reverse transcription quantitative polymerase chain reaction (RT-qPCR), Western blot, and fluorescent probes. Pathological changes, lesion volumes, and pelvic adhesions in the rat EM model were assessed using hematoxylin and eosin (HE) staining, ultrasound imaging, and Haber scoring.

Results: Erastin treatment of ESCs induced ferroptosis by upregulating SLC1A5 and c-Myc expression, increasing ROS levels, and altering glutamine metabolism. Overexpression of SLC1A5 enhanced sensitivity to ferroptosis, whereas SLC1A5 knockdown and NAC treatment reversed these effects. Mechanistically, c-Myc bound to the SLC1A5 promoter, forming positive feedback with ROS. In the rat model of EMs, Erastin treatment reduced ectopic lesion volume, pelvic adhesions, and inflammatory markers (TNF-α, IL-6, IL-1β). These therapeutic effects were mitigated by NAC, highlighting the importance of the ROS/c-Myc/SLC1A5 pathway.

Conclusions: This study confirmed the involvement of the ROS/c-Myc/SLC1A5 pathway in regulating EMs sensitivity to ferroptosis and demonstrated the potential of Erastin as a therapeutic agent. Targeting this pathway offers a promising approach for the treatment of EMs.