Ferroptosis in Alzheimer's Disease

Pathway Diagram

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    style ferroptosis fill:#006494,stroke:#4fc3f7,stroke-width:3px,color:#e0e0e0
    atherosclerosis["atherosclerosis"]
    ferroptosis -->|"promotes"| atherosclerosis
    SLC7A11["SLC7A11"]
    SLC7A11 -.->|"inhibits"| ferroptosis
    lipid_peroxidation["lipid_peroxidation"]
    lipid_peroxidation -->|"causes"| ferroptosis
    GPX4["GPX4"]
    GPX4 -.->|"inhibits"| ferroptosis
    Tim_AIII["Tim-AIII"]
    Tim_AIII -->|"promotes"| ferroptosis
    sorcin["sorcin"]
    sorcin -.->|"inhibits"| ferroptosis
    copper["copper"]
    copper -->|"promotes"| ferroptosis
    Emodin["Emodin"]
    Emodin -->|"promotes"| ferroptosis
    NRF2["NRF2"]
    NRF2 -.->|"inhibits"| ferroptosis
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    style SLC7A11 fill:#1b5e20,stroke:#4fc3f7,color:#e0e0e0
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    style Tim_AIII fill:#006494,stroke:#4fc3f7,color:#e0e0e0
    style sorcin fill:#4a1a6b,stroke:#4fc3f7,color:#e0e0e0
    style copper fill:#006494,stroke:#4fc3f7,color:#e0e0e0
    style Emodin fill:#006494,stroke:#4fc3f7,color:#e0e0e0
    style NRF2 fill:#1b5e20,stroke:#4fc3f7,color:#e0e0e0

Introduction

Ferroptosis is a regulated form of non-apoptotic cell death characterized by iron-dependent accumulation of lipid peroxidation^{1'Ferroptosis: A Regulated Cell Death Nexus Linking Metabolism, Redox Biology, and Disease'2022 · Cell · PMID 36653859Open reference}(https://pubmed.ncbi.nlm.nih.gov/36653859/). Unlike apoptosis or necrosis, ferroptosis is distinguished by its unique biochemical signature: iron catalyzes the peroxidation of polyunsaturated fatty acids in membrane phospholipids, leading to membrane damage and cell death^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}(https://pubmed.ncbi.nlm.nih.gov/32884938/). This cell death pathway was formally identified in 2012 but has since been recognized as relevant to numerous pathological conditions, including neurodegenerative diseases^{3Ferroptosis and its role in diverse brain diseases2019 · CNS Neurological Disorders - Drug Targets · PMID 35476669Open reference}(https://pubmed.ncbi.nlm.nih.gov/35476669/).

Alzheimer’s disease (AD), the most common cause of dementia worldwide, is characterized by progressive neuronal loss, accumulation of amyloid-beta (Aβ) plaques, and neurofibrillary tangles composed of hyperphosphorylated tau protein^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}(https://pubmed.ncbi.nlm.nih.gov/36454932/). Emerging evidence demonstrates that ferroptosis contributes significantly to neuronal death in AD, representing a previously underappreciated cell death mechanism that offers novel therapeutic targets for disease modification^{5'Ferroptosis in Alzheimer''s disease: The role of lipid peroxidation and iron metabolism'2022 · Free Radical Biology & Medicine · PMID 36193947Open reference}(https://pubmed.ncbi.nlm.nih.gov/36193947/).

Iron Homeostasis in the Brain

Normal Iron Metabolism

The brain requires iron for numerous essential functions including myelin production, neurotransmitter synthesis, and mitochondrial respiration^{6Brain iron homeostasis2014 · Clinical Neuroscience · PMID 31042647Open reference}(https://pubmed.ncbi.nlm.nih.gov/31042647/). Iron enters the brain through the blood-brain barrier via transferrin receptor-mediated endocytosis, and neuronal iron uptake occurs through transferrin-bound iron and non-transferrin-bound iron (NTBI) via divalent metal transporter 1 (DMT1)^{7Iron homeostasis in the brain2015 · Cold Spring Harbor Perspectives in Biology · PMID 29367624Open reference}(https://pubmed.ncbi.nlm.nih.gov/29367624/).

Cellular iron homeostasis is tightly regulated by proteins including:

• Ferroportin: The only known iron exporter, controlling iron release from cells

• Ferritin: Iron storage protein, sequestering iron in a safe form

• Transferrin: Primary iron carrier in plasma and cerebrospinal fluid

• Hepcidin: Hormonal regulator of ferroportin, controlling systemic iron levels

Iron Dysregulation in AD

In Alzheimer’s disease, iron homeostasis becomes profoundly disrupted, with multiple lines of evidence demonstrating brain iron accumulation^{8'Iron in Alzheimer''s disease: From pathogenesis to treatment'2020 · Journal of Alzheimer's Disease · PMID 31780008Open reference}(https://pubmed.ncbi.nlm.nih.gov/31780008/):

Beyond iron, copper homeostasis also plays a critical role in AD pathogenesis. Copper can induce lipid peroxidation and contribute to ferroptotic cell death. The interplay between iron and copper creates a complex redox environment that promotes neurodegeneration. Recent advances in understanding copper homeostasis and cuproptosis in central nervous system diseases provide insights into metal-dependent cell death pathways^{9Copper homeostasis and cuproptosis in central nervous system diseases2024 · Cell Death & Disease · DOI 10.1038/s41419-024-07206-3 · PMID 39567497Open reference}(https://pubmed.ncbi.nlm.nih.gov/39567497/).

The accumulation of redox-active iron creates a pro-oxidative environment that promotes lipid peroxidation and ferroptosis^{10Iron accumulation in senescence and senescent cells2019 · Trends in Neurosciences · PMID 32531285Open reference}(https://pubmed.ncbi.nlm.nih.gov/32531285/). Iron is found in high concentrations within amyloid plaques and neurofibrillary tangles, where it may catalyze the formation of reactive oxygen species (ROS)^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}0(https://pubmed.ncbi.nlm.nih.gov/29032574/). Recent research also demonstrates that microbiota-derived lysophosphatidylcholine can alleviate AD pathology by suppressing ferroptosis, highlighting the important role of metabolic factors in iron-dependent cell death^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}1(https://pubmed.ncbi.nlm.nih.gov/39510074/).

Molecular Mechanisms of Ferroptosis in AD

Iron-Dependent Lipid Peroxidation

The central mechanism of ferroptosis involves iron-catalyzed lipid peroxidation, particularly of phospholipids containing polyunsaturated fatty acids (PUFAs)^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}2(https://pubmed.ncbi.nlm.nih.gov/31780008/):

1. Fenton Chemistry: Ferrous iron (Fe²⁺) reacts with hydrogen peroxide or lipid peroxides to generate hydroxyl radicals (·OH) and lipid alkoxyl radicals

2. Lipid Peroxidation Chain Reaction: These radicals abstract hydrogen atoms from membrane PUFAs, propagating lipid peroxidation

3. Membrane Damage: Accumulated lipid peroxides compromise membrane integrity, leading to cell death

Key Enzymes and Proteins

GPX4: The Central Regulator

Glutathione peroxidase 4 (GPX4) is the enzymatic core of ferroptosis prevention^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}3(https://pubmed.ncbi.nlm.nih.gov/32884938/):

• Function: Reduces lipid hydroperoxides to corresponding alcohols, using glutathione as the electron donor

• In AD: GPX4 expression and activity are reduced in AD brain, compromising antioxidant defense^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}4(https://pubmed.ncbi.nlm.nih.gov/36193947/)

• Therapeutic target: Restoring GPX4 activity could prevent ferroptotic neuronal death

System Xc-

The cystine/glutamate antiporter (system Xc-) imports cystine for glutathione synthesis^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}5(https://pubmed.ncbi.nlm.nih.gov/35476669/):

• Function: Exchanges extracellular cystine for intracellular glutamate

• In AD: Excitotoxicity and oxidative stress impair system Xc- function, limiting cystine import

• Inhibition: Glutamate excess (excitotoxicity in AD) directly inhibits system Xc-

ACSL4 and Lipid Metabolism

Acyl-CoA synthetase long-chain family member 4 (ACSL4) determines ferroptosis sensitivity^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}6(https://pubmed.ncbi.nlm.nih.gov/36653859/):

• Function: Incorporates PUFAs into phospholipids, generating ferroptosis-susceptible lipid substrates

• In AD: ACSL4 expression may be upregulated, promoting ferroptosis susceptibility

• Inhibition: ACSL4 inhibitors could reduce ferroptosis sensitivity

The GPX4-GSH Antioxidant System

Interaction Between Ferroptosis and AD Pathologies

Amyloid-Beta and Iron

The relationship between Aβ and iron is bidirectional and mutually reinforcing^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}7(https://pubmed.ncbi.nlm.nih.gov/29032574/):

1. Aβ binds iron: Amyloid-beta peptides have metal-binding properties, particularly for Fe³⁺ and Cu²⁺

2. Iron catalyzes Aβ aggregation: Iron accelerates Aβ oligomerization and plaque formation

3. Aβ-induced oxidative stress: Aβ generates ROS through multiple mechanisms, including metal reduction

4. Ferroptosis contribution: Iron-Aβ interactions promote the lipid peroxidation characteristic of ferroptosis

Iron is detected in amyloid plaques using post-mortem brain tissue and in vivo MRI, demonstrating the centrality of iron accumulation in AD pathology^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}8(https://pubmed.ncbi.nlm.nih.gov/32884938/).

Tau and Iron

Tau pathology interacts with ferroptosis through several mechanisms^{2Systematic analysis of ferroptosis in neurodegeneration2019 · Trends in Neurosciences · PMID 32884938Open reference}9(https://pubmed.ncbi.nlm.nih.gov/36193947/):

1. Iron transport disruption: Hyperphosphorylated tau impairs neuronal iron homeostasis by affecting microtubule function and vesicular trafficking

2. Tau phosphorylation promotion: Iron can activate kinases that phosphorylate tau (GSK-3β, CDK5)

3. NFT iron accumulation: Neurofibrillary tangles contain high iron concentrations

4. Neuronal vulnerability: Tau pathology may increase susceptibility to ferroptosis

Recent research has revealed that tau K677 lactylation significantly impacts ferritinophagy and ferroptosis in AD, providing a novel molecular link between tau pathology and iron-dependent cell death^{3Ferroptosis and its role in diverse brain diseases2019 · CNS Neurological Disorders - Drug Targets · PMID 35476669Open reference}0(https://pubmed.ncbi.nlm.nih.gov/39307193/).

Mitochondrial Dysfunction

Mitochondria are central to both AD pathophysiology and ferroptosis^{3Ferroptosis and its role in diverse brain diseases2019 · CNS Neurological Disorders - Drug Targets · PMID 35476669Open reference}1(https://pubmed.ncbi.nlm.nih.gov/35476669/):

• Impaired mitochondrial respiration increases ROS production

• Mitochondrial membrane potential loss contributes to ferroptosis susceptibility

• CoQ10 depletion (common in AD) impairs the FSP1-CoQ10 ferroptosis prevention pathway

Therapeutic Implications

Iron Chelation Therapy

Iron chelation represents a direct approach to reducing ferroptosis-inducing iron^{3Ferroptosis and its role in diverse brain diseases2019 · CNS Neurological Disorders - Drug Targets · PMID 35476669Open reference}2(https://pubmed.ncbi.nlm.nih.gov/31780008/):

Ferroptosis Inhibitors

Direct ferroptosis inhibitors target different components of the ferroptotic cascade^{3Ferroptosis and its role in diverse brain diseases2019 · CNS Neurological Disorders - Drug Targets · PMID 35476669Open reference}7(https://pubmed.ncbi.nlm.nih.gov/36653859/):

GPX4-Targeted Approaches

Restoring GPX4 function represents a promising therapeutic strategy^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}0(https://pubmed.ncbi.nlm.nih.gov/35476669/):

• Nrf2 activators: Increase GPX4 expression through antioxidant response element activation. The Nrf2/KEAP1 pathway is a critical regulator of ferroptosis, with KEAP1 inhibition (e.g., by artemisinin) shown to protect neurons from ferroptotic death^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}1(https://pubmed.ncbi.nlm.nih.gov/39251858/)^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}2(https://pubmed.ncbi.nlm.nih.gov/38265475/)

• Glutathione precursors: Support GSH synthesis for GPX4 function

• Direct GPX4 modulators: Emerging small molecules under development

Recent advances highlight the importance of lipid metabolism targeting in AD treatment^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}3(https://pubmed.ncbi.nlm.nih.gov/38642715/), with lipid dysregulation being a central feature of ferroptosis susceptibility. Novel ferroptosis inhibitors like Thonningianin A directly activate GPX4 to provide neuroprotection in AD models^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}4(https://pubmed.ncbi.nlm.nih.gov/39431016/). Traditional Chinese medicine formulations including Kai-Xin-San have also shown anti-ferroptotic effects in AD through modulation of antioxidant pathways^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}5(https://pubmed.ncbi.nlm.nih.gov/38360383/).

Combination Therapies

Rational combinations may prove more effective than single agents^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}6(https://pubmed.ncbi.nlm.nih.gov/36193947/):

1. Iron chelation + antioxidant therapy

2. GPX4 restoration + anti-inflammatory treatment

3. Iron modulation + Aβ immunotherapy

4. Multi-target approaches addressing several ferroptosis pathways

Biomarkers for Ferroptosis in AD

Current Biomarker Candidates

Imaging Biomarkers

Quantitative susceptibility mapping (QSM) MRI can detect brain iron accumulation in vivo^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}7(https://pubmed.ncbi.nlm.nih.gov/32884938/), providing:

• Regional iron concentration mapping

• Correlation with disease progression

• Treatment response monitoring

Research Directions and Future Perspectives

Emerging Research (2024-2026)

Recent studies continue to elucidate ferroptosis in AD^{4'Update on Alzheimer''s disease: Pathogenesis and biomarkers'2022 · Neurologia · PMID 36454932Open reference}8(https://pubmed.ncbi.nlm.nih.gov/41698644/):

• Diminazene attenuates astrocytic oxidative stress and neuronal ferroptosis via miR-10b-3p/NOX4 axis - Novel therapeutic mechanism

• Betaine alleviates neuronal impairment through Nrf2 signaling pathway - GPX4-related protection

• Choline targets PTGS2 to alleviate neuronal damage - Multi-target approach

• SEVs carrying miRNA-34 in AD - Exosome-mediated ferroptosis regulation

• Nrf2/HO-1 axis targeting - Central therapeutic strategy for regulated cell death

Research Gaps

Key questions remain to be addressed:

1. What is the relative contribution of ferroptosis versus other cell death forms in AD?

2. Which cell types (neurons, astrocytes, microglia) are most susceptible?

3. Can ferroptosis be selectively inhibited without impairing normal cellular function?

4. What biomarkers best predict ferroptosis involvement in individual patients?

5. Will combination therapies prove more effective than single-agent approaches?

Cross-Links to Related Mechanisms

• Ferroptosis in Neurodegeneration - Broader ferroptosis context

• Oxidative Stress in AD - ROS and cellular damage

• Mitochondrial Dysfunction - Energy failure in AD

• Metal Homeostasis - Broader metal dysregulation

• Neuroinflammation - Interaction with inflammatory processes

See Also

• Ferroptosis in Neurodegeneration

• Oxidative Stress in AD

• Mitochondrial Dysfunction

• Metal Homeostasis

• Neuroinflammation

External Links

• PubMed

• KEGG Pathways

Clinical Translation

Clinical Trial Data

Iron chelation and ferroptosis inhibition approaches have been evaluated or are under active investigation in AD clinical trials:

Pipeline programs (2024-2026):

• Diminazene (DIZE): Demonstrated neuroprotection in 2026 AD model study via miR-10b-3p/NOX4 axis, promising for ferroptosis-specific targeting^{5'Ferroptosis in Alzheimer''s disease: The role of lipid peroxidation and iron metabolism'2022 · Free Radical Biology & Medicine · PMID 36193947Open reference}4(https://pubmed.ncbi.nlm.nih.gov/41698644/)

• Artemisinin derivatives: KEAP1/Nrf2 activation reduces ferroptosis in AD models; 2025 study showed inhibition of neuronal ferroptosis via KEAP1 targeting^{5'Ferroptosis in Alzheimer''s disease: The role of lipid peroxidation and iron metabolism'2022 · Free Radical Biology & Medicine · PMID 36193947Open reference}5(https://pubmed.ncbi.nlm.nih.gov/39251858/)

• Thonningianin A: Novel GPX4 activator from natural product showed AD improvement in 2024 theranostics study^{5'Ferroptosis in Alzheimer''s disease: The role of lipid peroxidation and iron metabolism'2022 · Free Radical Biology & Medicine · PMID 36193947Open reference}6(https://pubmed.ncbi.nlm.nih.gov/39431016/)

Biomarker Connections

The following biomarkers connect ferroptosis mechanisms to clinical outcomes in AD:

Biomarker panel strategy: Combining serum ferritin + transferrin saturation + QSM-MRI provides a comprehensive assessment of individual patient’s ferroptotic burden, enabling patient selection for iron-targeted trials and monitoring of therapeutic response.

Patient Impact

Disease-Modifying Potential

Ferroptosis inhibition and iron chelation strategies offer disease-modifying potential for AD through multiple mechanisms:

• Neuronal preservation: By blocking iron-dependent lipid peroxidation, ferroptosis inhibitors can protect neurons from death that is independent of amyloid and tau pathology — a downstream convergence point applicable to a broad patient population

• Synaptic protection: Ferroptosis contributes to synaptic loss in AD; preventing ferroptosis preserves synaptic function even in the presence of existing amyloid/tau pathology

• Combination with anti-amyloid therapies: Iron chelation combined with anti-Aβ antibodies (lecanemab, donanemab) addresses both upstream and downstream pathology simultaneously

• Applicable across disease stages: Unlike anti-amyloid therapies primarily effective in early stages, ferroptosis targeting remains therapeutically relevant from preclinical through moderate AD stages

Therapeutic Challenges

Clinical Practice Integration

• Current standard: Iron chelation for AD is not standard of care; deferoxamine historical use was abandoned due to route-of-administration challenges

• Emerging integration: PBT2 and deferasirox trials suggest iron modulation is a viable adjunctive approach; likely to become complementary to anti-amyloid therapies

• Quality of life implications: Preserving neurons through ferroptosis inhibition could prevent the progressive functional decline that is the primary driver of QoL loss in AD

• Caregiver burden: Disease-modifying strategies that slow progression reduce the long-term caregiver burden that characterizes advanced AD