IL-1β Protein - Interleukin-1 Beta

IL-1β Protein

Introduction

Il 1Β Protein Interleukin 1 Beta is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

Overview

This page provides comprehensive information about IL-1β Protein, including its structure, normal function in the nervous system, and its role in neurodegenerative diseases.

<div class="infobox infobox-protein">
<div class="infobox-header">IL-1β (Interleukin-1 Beta)</div>
<div class="infobox-content">
<table>
<tr><td><strong>Protein Name</strong></td><td>Interleukin-1 Beta</td></tr>
<tr><td><strong>Gene</strong></td><td>[IL1B](/genes/il1b)</td></tr>
<tr><td><strong>UniProt ID</strong></td><td><a href="https://www.uniprot.org/uniprot/P01584" target="_blank">P01584</a></td></tr>
<tr><td><strong>PDB Structure</strong></td><td><a href="https://www.rcsb.org/structure/5RVM" target="_blank">5RVM</a></td></tr>
<tr><td><strong>Molecular Weight</strong></td><td>17.5 kDa (mature)</td></tr>
<tr><td><strong>Subcellular Localization</strong></td><td>Secreted, Cytosol</td></tr>
<tr><td><strong>Protein Family</strong></td><td>IL-1 family</td></tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">3 edges</a></td>
</tr>
</table>
</div>
</div>

Structure

...

IL-1β Protein

Introduction

Il 1Β Protein Interleukin 1 Beta is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.

Overview

This page provides comprehensive information about IL-1β Protein, including its structure, normal function in the nervous system, and its role in neurodegenerative diseases.

<div class="infobox infobox-protein">
<div class="infobox-header">IL-1β (Interleukin-1 Beta)</div>
<div class="infobox-content">
<table>
<tr><td><strong>Protein Name</strong></td><td>Interleukin-1 Beta</td></tr>
<tr><td><strong>Gene</strong></td><td>[IL1B](/genes/il1b)</td></tr>
<tr><td><strong>UniProt ID</strong></td><td><a href="https://www.uniprot.org/uniprot/P01584" target="_blank">P01584</a></td></tr>
<tr><td><strong>PDB Structure</strong></td><td><a href="https://www.rcsb.org/structure/5RVM" target="_blank">5RVM</a></td></tr>
<tr><td><strong>Molecular Weight</strong></td><td>17.5 kDa (mature)</td></tr>
<tr><td><strong>Subcellular Localization</strong></td><td>Secreted, Cytosol</td></tr>
<tr><td><strong>Protein Family</strong></td><td>IL-1 family</td></tr>
<tr>
<td class="label">KG Connections</td>
<td><a href="/atlas" style="color:#4fc3f7">3 edges</a></td>
</tr>
</table>
</div>
</div>

Structure

IL-1β is synthesized as a 31 kDa precursor (pro-IL-1β) that is processed by caspase-1 into the 17.5 kDa mature form. The protein adopts a β-trefoil fold, characterized by 12 β-strands forming a barrel-like structure. This structure is common to the IL-1 family cytokines and provides the binding interface for the IL-1 receptor.

Key Structural Features:

• Propeptide: 116 aa N-terminal propeptide
• Mature Form: 153 aa after caspase-1 cleavage
• Receptor Binding Site: β-trefoil domain mediates interaction with IL-1R1
• No Signal Peptide: Secreted via non-conventional pathway (inflammasome-dependent)

Post-Translational Modifications:

• Caspase-1 Cleavage: Essential for bioactivity (Asp27-Ala28 bond)
• N-linked Glycosylation: May affect secretion efficiency
• Acetylation: Found on lysine residues, affects receptor binding

Normal Function

IL-1β is a potent pro-inflammatory cytokine that plays a central role in the innate immune response and neuroinflammation:

Immune System Functions:

• Inflammatory Cascade Initiation: Activates [NF-κB](/entities/nf-kb) and MAPK pathways
• Leukocyte Recruitment: Induces adhesion molecule expression
• Fever Generation: Acts on hypothalamic thermoregulatory centers
• Acute Phase Response: Stimulates hepatic acute-phase protein synthesis

Central Nervous System Functions:

• Microglial Activation: Potent activator of [microglia](/entities/microglia)
• Neuroimmune Communication: Mediates peripheral-immune to brain signaling
• Sleep Regulation: Promotes slow-wave sleep
• Synaptic Plasticity: Modulates learning and memory (biphasic effects)
• Neurogenesis: Regulates hippocampal neural stem cell proliferation

Signaling Mechanisms:

IL-1β signals through the type I IL-1 receptor (IL-1R1), which recruits the IL-1 receptor accessory protein (IL-1RAcP) to form a high-affinity signaling complex. This triggers activation of:

• MyD88-dependent pathway: Leads to NF-κB and MAPK activation
• TIRAP/Mal adapter: Additional signaling cascade
• IRAK kinases: Downstream phosphorylation events

Role in Disease

Alzheimer's Disease

IL-1β is a key driver of neuroinflammation in AD[^1]:

• [Amyloid-Beta](/proteins/amyloid-beta) Production: Promotes [amyloid precursor protein](/entities/app-protein) (APP) processing toward amyloidogenic [BACE1](/proteins/bace1-protein) cleavage, increasing Aβ generation[^2]
• [Tau](/proteins/tau) Pathology: Enhances [tau](/proteins/tau) phosphorylation through [GSK-3β](/entities/gsk3-beta) and [CDK5](/proteins/cdk5) activation, promoting [tau](/proteins/tau) aggregation into neurofibrillary tangles[^3]
• Synaptic Dysfunction: Impairs [long-term potentiation](/mechanisms/long-term-potentiation) (LTP) and promotes synaptic pruning by activated [microglia](/cell-types/microglia)[^4]
• [Blood-Brain Barrier](/entities/blood-brain-barrier) Permeability: Increases BBB permeability, allowing peripheral immune cell infiltration
• Genetic Risk: IL1B promoter polymorphisms (-511 C>T, -31 T>C) associated with increased AD risk[^5]
• CSF Biomarker: Elevated IL-1β in CSF correlates with disease severity and progression

Parkinson's Disease

IL-1β contributes to dopaminergic neurodegeneration[^6]:

• Nigral Inflammation: Elevated IL-1β in substantia nigra pars compacta of PD patients
• Microglial Activation: Perpetuates chronic microgliosis around dopaminergic [neurons](/entities/neurons)
• [α-Synuclein](/proteins/alpha-synuclein) Aggregation: Promotes misfolding and aggregation of α-synuclein
• Mitochondrial Dysfunction: Interferes with complex I activity, exacerbating mitochondrial defects
• Dopaminergic Toxicity: Direct toxic effects on dopaminergic neurons through caspase-3 activation

Amyotrophic Lateral Sclerosis (ALS)

• Motor Neuron Injury: Elevated in CSF and spinal cord tissue of ALS patients[^7]
• Glial Cell Activation: Activates [astrocytes](/entities/astrocytes) and [microglia](/cell-types/microglia-neuroinflammation), creating neurotoxic environment
• Excitotoxicity: Enhances glutamate-induced excitotoxicity through GLT-1 downregulation
• Therapeutic Target: IL-1β neutralizing antibodies and [NLRP3](/proteins/nlrp3) inhibitors in development

Multiple Sclerosis

• Demyelination: Promotes oligodendrocyte death and demyelination
• Lesion Formation: Contributes to blood-brain barrier breakdown
• Clinical Trials: Anti-IL-1 therapies evaluated for MS treatment

Diagnostic and Biomarker Applications

Cerebrospinal Fluid Biomarker:

• Elevated CSF IL-1β in AD, PD, and ALS compared to healthy controls
• Correlates with disease progression and severity
• Often measured alongside other inflammatory markers (IL-6, TNF-α)

Blood Biomarkers:

• Peripheral blood mononuclear cell (PBMC) IL-1β expression elevated
• Serum IL-1β levels show modest changes in neurodegeneration

Therapeutic Targeting

Approved and Experimental Therapies:

| Drug/Approach | Mechanism | Clinical Status | Application |
|---------------|-----------|-----------------|-------------|
| Anakinra | IL-1R antagonist | FDA-approved | Rheumatoid arthritis; trials for AD |
| Canakinumab | Anti-IL-1β antibody | FDA-approved | CAPS, Still's disease; cardiovascular trials |
| Gevokizumab | Anti-IL-1β antibody | Discontinued | Was in development for AD |
| MCC950 | [NLRP3 inflammasome](/entities/nlrp3-inflammasome) inhibitor | Preclinical | Blocks pro-IL-1β processing |
| P2X7 antagonists | Block IL-1β release | Clinical trials | Chronic pain, depression |
| Dapansutrile | NLRP3 inhibitor | Phase 2 | Inflammatory conditions |

Therapeutic Challenges:

• Blood-Brain Barrier: Poor CNS penetration of most IL-1 targeted therapies
• Physiological Functions: Complete IL-1 blockade may impair normal immune defense
• Biphasic Effects: Acute vs. chronic IL-1 signaling has different effects
• Alternative Targeting: Focus on NLRP3 inflammasome rather than direct IL-1β

Future Directions:

• NLRP3 Inhibitors: More specific targeting of pathological IL-1β production
• Brain-Penetrant Small Molecules: Developing CNS-deliverable IL-1R antagonists
• Gene Therapy: AAV-delivered IL-1 receptor antagonist (IL-1Ra) to CNS
• Combination Therapy: IL-1 targeting combined with amyloid/tau-directed therapies

Key Publications

Dinarello CA (2018). "IL-1β in inflammation." Int J Mol Sci. 19(8):EM 1809. PMID: 30061532(https://pubmed.ncbi.nlm.nih.gov/30061532/)

Mrak RE, Griffin WS (2005). "Glia and their cytokines in neurodegeneration." Neurobiol Aging. 26(3):349-354. PMID: 15639313(https://pubmed.ncbi.nlm.nih.gov/15639313/)

Heneka MT, et al. (2015). "Neuroinflammation in Alzheimer's disease." Lancet Neurol. 14(4):388-405. PMID: 25792098(https://pubmed.ncbi.nlm.nih.gov/25792098/)

Loddick SA, et al. (2006). "IL-1 mediates the chronic neurodegenerative effects of peripheral inflammation." Acta Neurochir Suppl. 96:289-292. PMID: 16671458(https://pubmed.ncbi.nlm.nih.gov/16671458/)

Nicoll JA, et al. (2000). "Association between interleukin-1 gene polymorphisms and Alzheimer's disease." Ann Neurol. 47(3):365-368. PMID: 10716255(https://pubmed.ncbi.nlm.nih.gov/10716255/)

Mogi M, et al. (1994). "Interleukin-1β, interleukin-6, epidermal growth factor and transforming growth factor-α are elevated in the brain from parkinsonian patients." Neurosci Lett. 180(2):147-150. PMID: 7700568(https://pubmed.ncbi.nlm.nih.gov/7700568/)

Poloni M, et al. (2000). "Circulating and CSF cytokines in amyotrophic lateral sclerosis." Acta Neurol Belg. 100(2):94-97. PMID: 10801059(https://pubmed.ncbi.nlm.nih.gov/10801059/)

Kitazawa M, et al. (2005). "LPS exacerbates [amyloid-beta](/proteins/amyloid-beta) and tau pathologies in a mouse model of Alzheimer's disease." Nat Med. 11(9):1032-1038. PMID: 16041382(https://pubmed.ncbi.nlm.nih.gov/16041382/)

Background

The study of Il 1Β Protein Interleukin 1 Beta 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.

References

^{[[1]](https://pubmed.ncbi.nlm.nih.gov/15033708/)} IL-1beta in neuroinflammation. PMID: 15033708(https://pubmed.ncbi.nlm.nih.gov/15033708/)

^{[[2]](https://pubmed.ncbi.nlm.nih.gov/10884128/)} BACE1 induction by IL-1beta. PMID: 10884128(https://pubmed.ncbi.nlm.nih.gov/10884128/)

^{[[3]](https://pubmed.ncbi.nlm.nih.gov/12510043/)} IL-1beta and tau pathology. PMID: 12510043(https://pubmed.ncbi.nlm.nih.gov/12510043/)

^{[[4]](https://pubmed.ncbi.nlm.nih.gov/15837572/)} Synaptic plasticity effects of IL-1. PMID: 15837572(https://pubmed.ncbi.nlm.nih.gov/15837572/)

^{[[5]](https://pubmed.ncbi.nlm.nih.gov/10625786/)} IL1B polymorphisms and AD risk. PMID: 10625786(https://pubmed.ncbi.nlm.nih.gov/10625786/)

^{[[6]](https://pubmed.ncbi.nlm.nih.gov/7700568/)} Cytokines in Parkinson's disease brain. PMID: 7700568(https://pubmed.ncbi.nlm.nih.gov/7700568/)

^{[[7]](https://pubmed.ncbi.nlm.nih.gov/10801059/)} Cytokines in ALS. PMID: 10801059(https://pubmed.ncbi.nlm.nih.gov/10801059/)

^{[[8]](https://pubmed.ncbi.nlm.nih.gov/22884264/)} LPS and IL-1 in AD models. PMID: 22884264(https://pubmed.ncbi.nlm.nih.gov/22884264/)

See Also

• IL1B Gene
• [Neuroinflammation Pathway](/mechanisms/neuroinflammation-pathway)
• [Microglia](/cell-types/microglia)
• [TNF Protein](/proteins/tnf-protein)
• [Alzheimer's Disease](/diseases/alzheimers-disease)
• [Parkinson's Disease](/diseases/parkinsons-disease)
• [ALS](/diseases/amyotrophic-lateral-sclerosis)
• [Multiple Sclerosis](/diseases/multiple-sclerosis)
• Inflammasome Pathway

External Links

• [UniProt: IL1B](https://www.uniprot.org/uniprot/P01584)
• [PDB: IL-1β](https://www.rcsb.org/structure/5RVM)
• [NCBI Protein: IL1B](https://www.ncbi.nlm.nih.gov/protein/NP_000567)
• [IL-1 Receptor Antagonist (Anakinra) Information](https://www.nlm.nih.gov/medlineplus/druginfo/meds/a604031.html)

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