Inflammatory Biomarkers in Parkinson's Disease

Parkinson’s disease is increasingly recognised as involving chronic neuroinflammation in both the central nervous system and periphery. Activation of microglia within the substantia nigra leads to release of pro-inflammatory cytokines and chemokines that contribute to dopaminergic neuron loss. Peripheral blood and cerebrospinal fluid assays have identified elevated levels of interleukins (for example IL-6, IL-1β), tumour necrosis factor-α, acute-phase proteins such as C-reactive protein and serum amyloid A, and chemokines including CCL2. These markers correlate with motor severity, cognitive decline and disease progression, offering potential for early diagnosis, patient stratification and monitoring of treatment response. Advances in radiotracer imaging further enable in vivo assessment of microglial activation, while anti-inflammatory therapies are under investigation as disease-modifying strategies.

Research from Nature Portfolio

An exploratory study of cerebrospinal fluid in patients with Parkinson’s disease, Parkinson’s disease dementia and atypical parkinsonian disorders reported increased levels of serum amyloid A and C-reactive protein in those with dementia and multiple system atrophy compared with non-demented patients and controls. YKL-40 was found to be reduced in non-demented Parkinson’s. These inflammatory markers showed positive correlations with α-synuclein, tau proteins and neurofilament light chain, and higher concentrations associated with more severe motor impairments and cognitive deficits. The findings underscore a link between central inflammation and clinical progression.

Inflammatory Biomarkers in Parkinson's Disease publication trend

The graph below shows the total number of articles in inflammatory biomarkers in parkinson's disease across all publications each year (not limited to Nature Index journals).

Technical terms

Cytokine: Small proteins secreted by cells that modulate immune and inflammatory responses.

Chemokine: A subgroup of cytokines that direct immune cell migration through chemotaxis.

C-reactive protein (CRP): An acute-phase protein produced by the liver in response to systemic inflammation.

Cerebrospinal fluid (CSF): Clear fluid surrounding the brain and spinal cord, sampled to assess central nervous system biomarkers.

Microglia: Resident immune cells of the central nervous system that mediate neuroinflammatory processes.

References

1. A systematic review and meta-analysis of inflammatory biomarkers in Parkinson’s disease. npj Parkinson's Disease (2023).
2. C-reactive protein as the biomarker of choice to monitor the effects of exercise on inflammation in Parkinson’s disease. Frontiers in Immunology (2023).
3. Biomarker of Neuroinflammation in Parkinson’s Disease. International Journal of Molecular Sciences (2022).
4. Cerebrospinal fluid concentrations of inflammatory markers in Parkinson’s disease and atypical parkinsonian disorders. Scientific Reports (2018).