Cellular degradation systems in ferroptosis

Abstract

In eukaryotic cells, macromolecular homeostasis requires selective degradation of damaged units by the ubiquitin-proteasome system (UPS) and autophagy. Thus, dysfunctional degradation systems contribute to multiple pathological processes. Ferroptosis is a type of iron-dependent oxidative cell death driven by lipid peroxidation. Various antioxidant systems, especially the system xc−-glutathione-GPX4 axis, play a significant role in preventing lipid peroxidation-mediated ferroptosis. The endosomal sorting complex required for transport-III (ESCRT-III)–dependent membrane fission machinery counteracts ferroptosis by repairing membrane damage. Moreover, cellular degradation systems play a dual role in regulating the ferroptotic response, depending on the cargo they degrade. The key ferroptosis repressors, such as SLC7A11 and GPX4, are degraded by the UPS. In contrast, the overactivation of selective autophagy, including ferritinophagy, lipophagy, clockophagy and chaperone-mediated autophagy, promotes ferroptotic death by degrading ferritin, lipid droplets, circadian proteins, and GPX4, respectively. Autophagy modulators (e.g., BECN1, STING1/TMEM173, CTSB, HMGB1, PEBP1, MTOR, AMPK, and DUSP1) also determine the ferroptotic response in a context-dependent manner. In this review, we provide an updated overview of the signals and mechanisms of the degradation system regulating ferroptosis, opening new horizons for disease treatment strategies.