S100B Protein

S100B Protein

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">S100B Protein</th>
</tr>
<tr>
<td class="label">Approach</td>
<td>Status</td>
</tr>
<tr>
<td class="label">Anti-S100B antibodies</td>
<td>Preclinical</td>
</tr>
<tr>
<td class="label">[RAGE](/genes/rage) inhibitors</td>
<td>Research</td>
</tr>
<tr>
<td class="label">Calcium channel modulators</td>
<td>Research</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/aging" style="color:#ef9a9a">Aging</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/cardiac" style="color:#ef9a9a">Cardiac</a>, <a href="/wiki/cardiovascular" style="color:#ef9a9a">Cardiovascular</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">192 edges</a></td>
</tr>
</table>

Pathway Diagram

S100B Protein

<table class="infobox infobox-protein">
<tr>
<th class="infobox-header" colspan="2">S100B Protein</th>
</tr>
<tr>
<td class="label">Approach</td>
<td>Status</td>
</tr>
<tr>
<td class="label">Anti-S100B antibodies</td>
<td>Preclinical</td>
</tr>
<tr>
<td class="label">[RAGE](/genes/rage) inhibitors</td>
<td>Research</td>
</tr>
<tr>
<td class="label">Calcium channel modulators</td>
<td>Research</td>
</tr>
<tr>
<td class="label">Associated Diseases</td>
<td><a href="/wiki/als" style="color:#ef9a9a">ALS</a>, <a href="/wiki/aging" style="color:#ef9a9a">Aging</a>, <a href="/wiki/als" style="color:#ef9a9a">Als</a>, <a href="/wiki/cardiac" style="color:#ef9a9a">Cardiac</a>, <a href="/wiki/cardiovascular" style="color:#ef9a9a">Cardiovascular</a></td>
</tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">192 edges</a></td>
</tr>
</table>

Pathway Diagram

Introduction

S100B Protein is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

Brain Atlas Resources

The [Allen Brain Atlas](https://human.brain-map.org/microarray/search/show?search_term=S100B) provides gene expression data for S100B:

• Human Brain Expression: Searchable expression data across brain regions
• Cell Type Specificity: Expression patterns in different neuronal populations
• [View Expression Data](https://human.brain-map.org/microarray/search/show?search_term=S100B)

Overview

S100B is a 91-amino acid EF-hand calcium-binding protein belonging to the S100 family of dimeric proteins. It is primarily produced by [Astrocytes](/entities/astrocytes) in the central nervous system and Schwann cells in the peripheral nervous system. S100B exhibits a dual nature: at nanomolar concentrations, it acts as a neurotrophic factor promoting neuronal survival, while at micromolar concentrations, it functions as a danger-associated molecular pattern (DAMP) that promotes neuroinflammation. This protein has been extensively studied in the context of [Alzheimer's Disease](/diseases/alzheimers-disease) and [Parkinson's Disease](/diseases/parkinsons-disease), where elevated levels are associated with disease progression and neuroinflammatory processes. [@steiner2011]

Structure and Function

S100B is a 91-amino acid EF-hand calcium-binding protein belonging to the S100 family of dimeric proteins. Each monomer contains two calcium-binding sites: one in the N-terminal domain and one in the C-terminal EF-hand motif. [@goncalves2008]

Normal Function

• Calcium signaling: S100B acts as a calcium sensor, undergoing conformational changes upon calcium binding that enable interaction with target proteins
• Neurotrophic effects: At nanomolar concentrations, S100B promotes neuronal survival, neurite extension, and glial cell proliferation
• Cell cycle regulation: Modulates cell proliferation and differentiation in the nervous system
• Cytoprotection: Exhibits anti-apoptotic properties through inhibition of caspase-3 and activation of PI3K/Akt signaling

Role in Neurodegenerative Diseases

Alzheimer's Disease

Elevated S100B expression is observed in AD brain tissue, particularly in astrocytes surrounding amyloid plaques: [@wiehager2009]

• Astrogliosis marker: Reactive astrocytes expressing S100B are found in vicinity to [Aβ](/proteins/amyloid-beta) plaques
• Pro-inflammatory effects: At micromolar concentrations, S100B acts as a danger-associated molecular pattern (DAMP), activating [microglia](/entities/microglia) through [RAGE](/genes/rage) and [TLR4](/entities/tlr4) receptors
• [Aβ](/proteins/amyloid-beta) interaction: S100B can bind to Aβ peptides, potentially influencing plaque formation and toxicity
• Therapeutic target: Reducing S100B overexpression may mitigate neuroinflammation in AD

Parkinson's Disease

S100B is upregulated in PD brains:

• Dopaminergic neuron vulnerability: Increased S100B in substantia nigra correlates with dopaminergic neuron loss
• [α-Synuclein](/proteins/alpha-synuclein) interaction: S100B may influence α-synuclein aggregation dynamics
• Neuroinflammation: Promotes microglial activation and subsequent neuroinflammation

Other Neurodegenerative Conditions

• Amyotrophic Lateral Sclerosis (ALS): Elevated in motor [neurons](/entities/neurons) and glial cells
• Multiple Sclerosis: Marker of astrocyte activation
• Traumatic Brain Injury: Released following injury, serves as biomarker

Biomarker Potential

S100B has been investigated as a peripheral biomarker for CNS injury and neurodegeneration:

• [Blood-brain barrier](/entities/blood-brain-barrier) permeability: Elevated serum S100B indicates BBB disruption
• Diagnostic utility: Higher levels in AD vs. controls, but limited specificity
• Prognostic value: Correlates with disease progression in some studies
• Limitations: Low specificity; elevated in various neurological conditions

Therapeutic Targeting

Key Publications

Background

The study of S100B Protein has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.

Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.

See Also

• [Astrocytes](/cell-types/astrocytes)
• [Neuroinflammation](/mechanisms/neuroinflammation-pathway)
• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [TREM2](/genes/trem2)
• [Glial Fibrillary Acidic Protein](/entities/glial-fibrillary-acidic-protein)
• Parkinson's Disease Biomarkers

External Links

• [UniProt: P04271 (S100B)](https://www.uniprot.org/uniprotkb/P04271)
• [GeneCards: S100B](https://www.genecards.org/cgi-bin/carddisp.pl?gene=S100B)
• [PubMed S100B Neurodegeneration](https://pubmed.ncbi.nlm.nih.gov/?term=S100B+neurodegeneration)

References