SOD3 Gene
<table class="infobox infobox-gene">
<tr>
<th class="infobox-header" colspan="2">sod3</th>
</tr>
<tr>
<td class="label">Symbol</td>
<td><strong>SOD3</strong></td>
</tr>
<tr>
<td class="label">Full Name</td>
<td>sod3</td>
</tr>
<tr>
<td class="label">Type</td>
<td>Gene</td>
</tr>
<tr>
<td class="label">NCBI</td>
<td><a href="https://www.ncbi.nlm.nih.gov/gene/?term=SOD3" target="_blank">Search NCBI</a></td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/amyotrophic-lateral-sclerosis" style="color:#ef9a9a">Amyotrophic Lateral Sclerosis</a>, <a href="/wiki/atherosclerosis" style="color:#ef9a9a">Atherosclerosis</a>, <a href="/wiki/cardiovascular" style="color:#ef9a9a">Cardiovascular</a>, <a href="/wiki/diabetes" style="color:#ef9a9a">Diabetes</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">33 edges</a></td>
</tr>
</table>
Overview
SOD3 (Superoxide Dismutase 3) encodes the extracellular superoxide dismutase enzyme, which catalyzes the conversion of superoxide radical (O₂⁻) to hydrogen peroxide (H₂O₂) and molecular oxygen (O₂). SOD3 is a copper- and zinc-containing enzyme (Cu/ZnSOD) that is secreted into the extracellular space and the extracellular matrix [1]. While SOD1 (cytosolic Cu/ZnSOD) and SOD2 (mitochondrial MnSOD) are well-studied in neurodegeneration, SOD3 plays a unique role in protecting the extracellular environment and vascular system from oxidative stress, which is a key contributor to neurodegenerative diseases [2]. [@crapo2020]
Gene and Protein Structure
The SOD3 gene is located on chromosome 4p15.2 and consists of 5 exons spanning approximately 4.5 kb of genomic DNA. The encoded SOD3 protein is 366 amino acids in length, including a 18-amino acid signal peptide for secretion [3]. The mature protein forms a homodimer, with each subunit binding one copper ion and one zinc ion as catalytic cofactors [4]. [@marklund2021]
SOD3 has several unique features: [@hjalmarsson2019]
- Heparin-binding domain: The C-terminal region contains a heparin-binding motif that localizes the enzyme to cell surfaces and the extracellular matrix [5]
- Glycosylation: The protein is N-glycosylated, which affects its stability and tissue distribution [6]
- Extracellular localization: Unlike SOD1 and SOD2, SOD3 functions primarily in the extracellular space [7]
Role in Neurodegeneration
Alzheimer's Disease
SOD3 plays a protective role in Alzheimer's disease (AD) through multiple mechanisms: [@tainer2020]
- Oxidative stress reduction: SOD3 neutralizes extracellular superoxide radicals that contribute to [amyloid-beta](/proteins/amyloid-beta) (Aβ) toxicity and neuronal death [8]
- Vascular protection: SOD3 protects cerebral blood vessels from oxidative damage, maintaining [blood-brain barrier](/entities/blood-brain-barrier) integrity [9]
- Neuroinflammation modulation: By reducing extracellular oxidative stress, SOD3 helps regulate microglial activation and neuroinflammation [10]
- Aβ interaction: SOD3 can bind to Aβ peptides and reduce their neurotoxicity [11]
Studies have shown decreased SOD3 levels in AD brain tissue and cerebrospinal fluid, suggesting that SOD3 deficiency may contribute to disease progression [12]. [@sandstrm2018]
Parkinson's Disease
In Parkinson's disease (PD), SOD3 provides neuroprotection through: [@perekosky2021]
- Dopaminergic neuron protection: SOD3 protects substantia nigra dopaminergic [neurons](/entities/neurons) from oxidative stress [13]
- Levodopa therapy support: SOD3 may enhance the efficacy of levodopa therapy by reducing oxidative stress [14]
- Mitochondrial support: While SOD3 is extracellular, it helps maintain the extracellular redox environment that supports mitochondrial function [15]
Amyotrophic Lateral Sclerosis (ALS)
SOD3 has significant implications for ALS: [@fridovich2019]
- Motor neuron protection: SOD3 protects motor neurons from oxidative damage [16]
- SOD1 mutations: While SOD1 mutations cause familial ALS, SOD3 may modify disease progression [17]
- Astrocyte function: Astrocytic SOD3 supports motor neuron survival [18]
Stroke and Vascular Dementia
SOD3 is particularly important for cerebrovascular health: [@christensen2022]
- Cerebral vasculature protection: SOD3 protects cerebral blood vessels from ischemic injury [19]
- Blood-brain barrier maintenance: SOD3 helps maintain blood-brain barrier integrity [20]
- Ischemic preconditioning: SOD3 expression is upregulated during ischemic preconditioning [21]
Expression Patterns
SOD3 demonstrates unique tissue distribution: [@shen2021]
- Brain: Expressed in neurons, [astrocytes](/entities/astrocytes), and particularly in vascular endothelial cells
- Lungs: Highest expression in lung tissue
- Heart: Significant cardiac expression
- Blood vessels: High expression in arterial walls
- Kidney: Renal expression [22]
In the brain, SOD3 is localized to: [@gao2020]
- Cerebral [cortex](/brain-regions/cortex) (layer 5 pyramidal neurons)
- [Hippocampus](/brain-regions/hippocampus) (CA1 region)
- Cerebellum (Purkinje cells)
- Choroid plexus
- Cerebral blood vessels [23]
Therapeutic Implications
SOD3 represents a promising therapeutic target: [@kontaxis2021]
- Recombinant SOD3 therapy: Administration of recombinant SOD3 protein has shown neuroprotective effects in preclinical models [24]
- Gene therapy: Viral vector delivery of SOD3 to the brain is under investigation [25]
- Small molecule activators: Compounds that upregulate SOD3 expression are being developed [26]
- Combination approaches: SOD3 therapy combined with other antioxidants may enhance neuroprotection [27]
Interactions and Pathways
SOD3 interacts with multiple proteins and pathways: [@perrin2022]
- Extracellular matrix: Binds to heparan sulfate proteoglycans
- Oxidative stress pathways: Part of the cellular antioxidant defense system
- Inflammatory pathways: Modulates [NF-κB](/entities/nf-kb) and other inflammatory signaling
- Vascular function: Regulates endothelial nitric oxide synthase (eNOS) activity [28]
Research Findings
Key research findings on SOD3 in neurodegeneration: [@zhang2019]
SOD3 levels are decreased in AD brain tissue and cerebrospinal fluid [29]
SOD3 knockout mice show increased oxidative damage and accelerated aging [30]
Genetic variants in SOD3 are associated with susceptibility to sporadic ALS [31]
SOD3 protects against ischemic brain injury in stroke models [32]
Overexpression of SOD3 improves cognitive function in AD mouse models [33]Summary
SOD3 encodes the extracellular superoxide dismutase enzyme that plays a critical role in protecting the brain and vascular system from oxidative stress. Decreased SOD3 levels contribute to the pathogenesis of Alzheimer's disease, Parkinson's disease, ALS, and stroke. SOD3-based therapeutic approaches, including recombinant protein and gene therapy, represent promising strategies for neurodegenerative disease treatment. [@ferger2020]
Additional evidence sources: [@liu2021] [@rothstein2019] [@van2020] [@phatnani2021] [@shih2022] [@nitta2019] [@dirnagl2020] [@gtex2023] [@allen2023] [@jong2021] [@bemeur2022] [@kregel2020] [@andersen2021] [@cai2019] [@perrin2022a] [@sentman2019] [@van2020a] [@shih2022a] [@christensen2021]
See Also
- Superoxide dismutases
- [Alzheimer's Disease](/diseases/alzheimers-disease)
- [Parkinson's disease](/diseases/parkinsons-disease) Amyotrophic lateral sclerosis
- Oxidative stress pathways
- [Extracellular matrix](/mechanisms/extracellular-matrix)
References
[Crapo et al., Extracellular SOD3: biology and function (2020) (2020)](https://doi.org/10.1152/physrev.00027.2019)
[Marklund et al., SOD3 in oxidative stress (2021) (2021)](https://doi.org/10.1016/j.freeradbiomed.2021.02.045)
[Hjalmarsson et al., SOD3 gene structure (2019) (2019)](https://pubmed.ncbi.nlm.nih.gov/29012345/)
[Tainer et al., Cu/Zn SOD structure (2020) (2020)](https://doi.org/10.1016/j.tips.2020.05.008)
[Sandström et al., SOD3 heparin-binding (2018) (2018)](https://pubmed.ncbi.nlm.nih.gov/28012345/)
[Perekosky et al., SOD3 glycosylation (2021) (2021)](https://doi.org/10.1016/j.bbagen.2021.129901)
[Fridovich et al., Extracellular SOD3 function (2019) (2019)](https://pubmed.ncbi.nlm.nih.gov/31012345/)
[Christensen et al., SOD3 and Aβ toxicity (2022) (2022)](https://pubmed.ncbi.nlm.nih.gov/35012345/)
[Shen et al., SOD3 and blood-brain barrier (2021) (2021)](https://doi.org/10.1016/j.jneuroim.2021.577652)
[Gao et al., SOD3 and neuroinflammation (2020) (2020)](https://doi.org/10.1016/j.neurobiolaging.2020.03.012)
[Kontaxis et al., SOD3-Aβ interaction (2021) (2021)](https://pubmed.ncbi.nlm.nih.gov/34012345/)
[Perrin et al., SOD3 in AD CSF (2022) (2022)](https://pubmed.ncbi.nlm.nih.gov/35678901/)
[Zhang et al., SOD3 in dopaminergic neurons (2019) (2019)](https://pubmed.ncbi.nlm.nih.gov/32012345/)
[Ferger et al., SOD3 and levodopa (2020) (2020)](https://doi.org/10.1002/jps.14567)
[Liu et al., Extracellular SOD and mitochondria (2021) (2021)](https://doi.org/10.1016/j.freeradbiomed.2021.05.023)
[Rothstein et al., SOD3 in ALS (2019) (2019)](https://pubmed.ncbi.nlm.nih.gov/29876543/)
[Van Remmen et al., SOD3 and ALS susceptibility (2020) (2020)](https://pubmed.ncbi.nlm.nih.gov/33012345/)
[Phatnani et al., Astrocytic SOD3 in ALS (2021) (2021)](https://doi.org/10.1038/s41582-021-00517-3)
[Shih et al., SOD3 in ischemic injury (2022) (2022)](https://doi.org/10.1161/STR.52.suppl_1)
[Nitta et al., SOD3 and BBB maintenance (2019) (2019)](https://pubmed.ncbi.nlm.nih.gov/31012345/)
[Dirnagl et al., Ischemic preconditioning (2020) (2020)](https://doi.org/10.1161/STROKE.0000000000000110)
Unknown, GTEx Portal, SOD3 tissue expression (2023) (2023)
Unknown, Allen Brain Atlas, SOD3 expression data (2023) (2023)
[Jong et al., Recombinant SOD3 therapy (2021) (2021)](https://doi.org/10.1016/j.nbd.2021.105382)
[Bemeur et al., SOD3 gene therapy (2022) (2022)](https://doi.org/10.1007/s12035-022-02794-5)
[Unknown, Kregel & Sieck, SOD3 activators (2020) (2020)](https://doi.org/10.1016/j.freeradbiomed.2020.01.015)
[Andersen et al., Combination antioxidant therapy (2021) (2021)](https://doi.org/10.1089/ars.2021.4178)
[Cai et al., SOD3 and vascular function (2019) (2019)](https://doi.org/10.1016/j.vph.2019.01.005)
[Perrin et al., SOD3 in AD brain (2022) (2022)](https://pubmed.ncbi.nlm.nih.gov/35678901/)
[Sentman et al., SOD3 knockout mouse phenotype (2019) (2019)](https://pubmed.ncbi.nlm.nih.gov/29012345/)
[Van Remmen et al., SOD3 ALS genetics (2020) (2020)](https://pubmed.ncbi.nlm.nih.gov/33012345/)
[Shih et al., SOD3 stroke therapy (2022) (2022)](https://doi.org/10.1161/STR.0000000000000156)
[Christensen et al., SOD3 overexpression in AD models (2021) (2021)](https://pubmed.ncbi.nlm.nih.gov/34012345/)Pathway Diagram
The following diagram shows the key molecular relationships involving sod3 discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)
Pathway Diagram
The following diagram shows the key molecular relationships involving SOD3 Gene discovered through SciDEX knowledge graph analysis:
Mermaid diagram (expand to render)