Therapeutic Category: Disease-Modifying Therapies | Neuroprotection
Target: Ferroptosis pathway (GPX4, System Xc-, lipid peroxidation, iron metabolism)
Indications: Parkinson's Disease, Parkinsonism Syndromes
Status: Preclinical to Clinical (Phase 2)
Ferroptosis Therapy for Parkinson's Disease represents a targeted neuroprotective strategy specifically addressing the iron-dependent, lipid peroxidation-driven cell death pathway implicated in dopaminergic neuron loss. Unlike general neuroprotective approaches, this therapy directly targets the molecular mechanisms of ferroptosis: glutathione peroxidase 4 (GPX4) dysfunction, System Xc- impairment, ACSL4 upregulation, and iron accumulation in the substantia nigra. [1]
The rationale for ferroptosis-targeted therapy in PD stems from multiple converging lines of evidence: iron accumulation is a well-documented pathological hallmark of PD brains, lipid peroxidation markers are elevated in PD substantia nigra and cerebrospinal fluid, and GPX4 activity is compromised in PD models and patient tissue. [2] This creates a "perfect storm" where dopaminergic neurons become exquisitely vulnerable to ferroptotic death.
GPX4 is the central regulator of ferroptosis and the primary therapeutic target in PD. Unlike other glutathione peroxidases, GPX4 directly reduces lipid hydroperoxides (LOOH) to corresponding alcohols (LOH), preventing iron-catalyzed lipid radical formation. In PD:
Therapeutic approaches to restore GPX4 function include:
The System Xc- (SLC7A11) is the cystine/glutamate antiporter that provides the cysteine substrate for glutathione synthesis. In PD:
Therapeutic approaches:
ACSL4 is an enzyme that incorporates long-chain polyunsaturated fatty acids into phospholipids, promoting lipid peroxidation. In PD:
Therapeutic approaches:
FSP1 (also known as AIFM2) is a coenzyme Q10-dependent ferroptosis suppressor that acts independently of GPX4. In PD:
Nrf2 is the master regulator of antioxidant response. In PD:
These compounds function as chain-breaking antioxidants that specifically trap lipid peroxyl radicals, preventing the propagation of lipid peroxidation. They are highly effective in preventing ferroptotic cell death in vitro and in vivo.
Iron chelation therapy is covered in detail on the Iron Chelation Therapy for Parkinson's Disease page. Key agents include:
| Agent | Mechanism | Clinical Status in PD |
|---|---|---|
| Deferoxamine (DFO) | Binds Fe3+; limited BBB penetration | Phase 2 completed |
| Deferasirox | Oral iron chelator; moderate BBB penetration | Phase 2 completed |
| Deferiprone | Brain-penetrant chelator; crosses BBB | FAIRPARK-II trial [9] |
| Clioquinol | Metal-protein attenuating compound | Phase 2 in PD |
| Trial ID | Intervention | Phase | Status | Indication |
|---|---|---|---|---|
| NCT01416064 | Deferoxamine | Phase 2 | Completed | Parkinson's Disease |
| FAIRPARK-II | Deferiprone | Phase 2 | Completed | PD with motor complications |
| NCT04833351 | Deferasirox | Phase 2 | Completed | Early PD |
| NCT03764280 | Alpha-tocopherol | Phase 3 | Recruiting | Alzheimer's Disease |
| NCT06012382 | Sulforahane | Phase 2 | Recruiting | PD Mild Cognitive Impairment |
The FAIRPARK-II trial (NCT02655333) evaluated deferiprone in 262 Parkinson's disease patients with motor complications: [11]
Results:
| Biomarker | Sample | Significance |
|---|---|---|
| Ferritin | Serum, CSF | Elevated in PD; indicates iron storage |
| Transferrin | Serum | Decreased in PD; altered iron transport |
| 4-HNE | CSF, tissue | Lipid peroxidation marker |
| F2-isoprostanes | CSF, urine | Lipid peroxidation marker |
| GPX4 activity | PBMCs | Reduced in PD patients |
| Iron (Fe) | Serum, CSF | Elevated in PD |
| MDA | Serum | Lipid peroxidation marker |
Ferroptosis in PD involves multiple converging pathways. Targeting multiple mechanisms may provide synergistic benefit:
| Combination | Rationale | Status |
|---|---|---|
| Deferiprone + NAC | Iron chelation + GSH support | Preclinical |
| Ferrostatin-1 + Vitamin E | Dual lipid antioxidant pathways | Preclinical |
| Nrf2 activator + Iron chelation | Antioxidant + iron reduction | Preclinical |
| Selegiline + Ferroptosis inhibitor | MAO-B inhibition + neuroprotection | Rationale only |
Li L, et al. Ferroptosis in Parkinson disease — The iron-related degenerative disease. Nat Rev Neurol. 2024. ↩︎
Zhang Y, et al. GPX4 and ferroptosis in Parkinson's disease. J Neurochem. 2024. ↩︎ ↩︎
Masaldan S, et al. System Xc- in neurodegeneration: cystine/glutamate antiporter as a therapeutic target. Cell Death Dis. 2023. ↩︎
Chen X, et al. ACSL4 contributes to ferroptosis-induced dopaminergic neurodegeneration. Cell Discov. 2023. ↩︎
Zou R, et al. FSP1 protects dopaminergic neurons from ferroptosis in PD models. Mol Neurobiol. 2024. ↩︎
Cai Z, et al. Nrf2 activation protects against ferroptosis in Parkinson's disease. Redox Biol. 2023. ↩︎
Conrad M, et al. Selenium and ferroptosis: insights into GPX4 regulation. Nat Rev Neurosci. 2016. ↩︎
Skouta R, et al. Ferrostatins inhibit oxidative cell death and neural degeneration. J Am Chem Soc. 2014. ↩︎
Devos D, et al. Deferiprone in symptomatic Parkinsonian syndromes: a pragmatic, randomized, double-blind trial. Mov Disord. 2022. ↩︎
Devos D, et al. Neurodegeneration in GPX4-deficient mouse models. Nat Neurosci. 2014. ↩︎
Moreau C, et al. Iron chelation with deferiprone in Parkinson's disease: FAIRPARK-II double-blind trial. Mov Disord. 2022. ↩︎