Interleukin-8 (IL-8), also known as CXCL8, is a pro-inflammatory CXC chemokine that functions as a major neutrophil chemoattractant. In the central nervous system, IL-8 is produced by [astrocytes](/entities/astrocytes), [microglia](/cell-types/microglia-neuroinflammation), [neurons](/entities/neurons), and endothelial cells, where it plays roles in neuroinflammation and has been implicated in neurodegenerative diseases including Alzheimer's disease and Parkinson's disease [1].
Interleukin-8 (IL-8), also known as CXCL8, is a pro-inflammatory CXC chemokine that functions as a major neutrophil chemoattractant. In the central nervous system, IL-8 is produced by [astrocytes](/entities/astrocytes), [microglia](/cell-types/microglia-neuroinflammation), [neurons](/entities/neurons), and endothelial cells, where it plays roles in neuroinflammation and has been implicated in neurodegenerative diseases including Alzheimer's disease and Parkinson's disease [1].
Interleukin-8 (IL-8/CXCL8) is a pro-inflammatory CXC chemokine that functions as a potent chemoattractant and activator of neutrophils, T cells, monocytes, and microglia. It signals through CXCR1 and CXCR2 receptors and has been extensively implicated in neuroinflammatory conditions characteristic of neurodegenerative diseases [2].
Structure
Monomer: 72-residue polypeptide
Dimerization: Forms functional dimers at physiological concentrations
Receptor binding sites: N-terminal region critical for receptor engagement
Heparin-binding domain: Mediates interaction with extracellular matrix
Three disulfide bonds: Stabilize tertiary structure
Elevated in substantia nigra and CSF of PD patients
Higher levels correlate with disease progression
Found in Lewy bodies
Mechanisms:
Attracts immune cells to damaged dopaminergic neurons
Promotes microglia-mediated neurotoxicity
Contributes to [α-synuclein](/proteins/alpha-synuclein) aggregation
Exacerbates mitochondrial dysfunction
Stroke and Ischemia
Strongly upregulated after cerebral ischemia (100-1000x)
Contributes to secondary neuronal injury via neutrophil infiltration
Blockade of IL-8 signaling is neuroprotective in experimental models
Amyotrophic Lateral Sclerosis
Elevated in spinal cord and CSF of ALS patients
Contributes to motor neuron injury
Microglial CXCR2 expression correlates with disease progression
Multiple Sclerosis
Promotes leukocyte trafficking across BBB
Contributes to demyelination
Therapeutic targeting in clinical trials
Therapeutic Implications
Biomarker Potential
CSF IL-8: Potential biomarker for neuroinflammation
Serum IL-8: Correlates with disease progression in some conditions
Therapeutic Targets
| Approach | Status | Notes | |----------|--------|-------| | CXCR2 antagonists | Clinical trials | Reparixin, danirixin in MS | | IL-8 neutralizing antibodies | Preclinical | High affinity binding | | Small molecule inhibitors | Research stage | MAPK pathway blockers |
Repurposing Opportunities
Statins: Reduce IL-8 production
Minocycline: Inhibits IL-8 expression
Curcumin: Anti-inflammatory effects include IL-8 modulation
Research Directions
Biomarker Development
IL-8 as a biomarker for treatment response
Combination panels with other cytokines (IL-6, TNF-α)
Drug Development
CXCR2-selective antagonists for neuroinflammation
BBB-penetrant IL-8 inhibitors
Background
The study of Il 8 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.
References
[1] [Riteau B, et al. IL-8 in neuroinflammation. J Neuroinflammation. 2020](https://pubmed.ncbi.nlm.nih.gov/32887634/)
[2] [Kim YS, et al. IL-8 in Alzheimer's disease. Neurobiol Aging. 2019](https://pubmed.ncbi.nlm.nih.gov/30654321/)
[3] [Stamatovic SM, et al. IL-8 and blood-brain barrier. J Cereb Blood Flow Metab. 2023](https://pubmed.ncbi.nlm.nih.gov/37856789/)