What is ferroptosis, and what does it have to do with cartilage glutathione?
Ferroptosis is an iron-dependent form of cell death driven by damage to cell membranes. GPX4, an enzyme that needs glutathione to work, is the cell's main brake on it. GPX4 was lower in damaged cartilage from osteoarthritis patients than in undamaged cartilage, and lowering it worsened osteoarthritis in an animal model (Miao 2022).
A newer kind of cell death
Ferroptosis happens when iron-driven lipid peroxidation overwhelms a cell's membranes. GPX4 uses glutathione to neutralise the lipid peroxides that drive it. In a 2022 study, ferroptosis was closely associated with osteoarthritis, GPX4 was significantly lower in osteoarthritic cartilage from 55 patients, and lowering GPX4 made chondrocytes more sensitive to oxidative stress, aggravated cartilage matrix breakdown and worsened osteoarthritis in an animal model (Miao 2022).
Where glutathione comes in
In cartilage cells under mechanical stress, NAC delivered by targeted nanoparticles restored glutathione, raised GPX4 and suppressed ferroptosis; the protective effect disappeared in mice lacking GPX4 (Wang 2026). Dihydrolipoic acid also limited glutathione and GPX4 loss and suppressed ferroptosis in mouse cartilage cells (Chen 2026).
Other questions people ask
Is ferroptosis proven in human joints?
The human evidence so far is lower GPX4 in damaged osteoarthritic cartilage (Miao 2022). The cause-and-effect work is in cells and animals.
Sources
- Miao Y, Chen Y, Xue F et al. Contribution of ferroptosis and GPX4's dual functions to osteoarthritis progression. EBioMedicine 2022.
- Wang S, Zhang F, Zhou X et al. Chondrocyte-Targeted Nanoparticles Loaded with N-Acetylcysteine Protect Articular Cartilage and Attenuate Osteoarthritis by Inhibiting Ferroptosis via Glutathione Maintenance. Small Sci 2026.
- Chen Y, Fang J, Zhou Z et al. Dihydrolipoic acid suppresses ferroptosis in chondrocytes to ameliorate the progression of osteoarthritis by modulating the FOXO1/TXNIP signaling pathway. Free Radic Biol Med 2026.
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