Neurovascular Mechanisms in Parkinson's Disease

Parkinson’s disease is traditionally viewed through the lens of dopaminergic neuron loss in the substantia nigra, yet growing evidence places neurovascular dysfunction centre stage in its pathogenesis. The neurovascular unit—which comprises endothelial cells, pericytes, astrocytes, microglia and the basement membrane—maintains cerebral blood flow, barrier integrity and metabolic support. In Parkinson’s disease, pathological changes in this unit include disruption of tight junction proteins, pericyte activation or loss, altered transporter expression and inflammatory glial responses. These alterations facilitate leakage of blood-borne factors into the parenchyma, provoke immune cell infiltration and amplify α-synuclein aggregation. Conversely, vascular regression and reduced capillary density may exacerbate hypoperfusion and metabolic stress in vulnerable neuronal populations. Models ranging from organ-on-chip systems to genetically modified rodents demonstrate that astrocyte-derived inflammatory mediators and α-synuclein aggregates both compromise barrier properties and impair endothelial function. The resulting feed-forward cycle of neuroinflammation and vascular permeability not only contributes to neurodegeneration but also influences the delivery and efficacy of therapeutic agents. Understanding the interplay between vascular cells and neurons thus opens avenues for interventions aimed at preserving barrier integrity, modulating glial responses or restoring microvascular perfusion in Parkinson’s disease.

Research from Nature Portfolio

Recent studies using microfluidic brain-chip platforms have recapitulated the cellular complexity of the substantia nigra, enabling detailed analysis of barrier dysfunction in Parkinson’s disease. One human three-dimensional blood–brain barrier model revealed that astrocytes harbouring pathogenic mutations adopt a pro-inflammatory phenotype, fail to support capillary formation and drive endothelial leakiness; modulation of MEK1/2 signalling in these astrocytes restored barrier integrity. Another organ-on-chip system incorporating human dopaminergic neurons, astrocytes, microglia, pericytes and endothelial cells demonstrated that exposure to α-synuclein fibrils induces mitochondrial impairment, cytokine release and selective breakdown of tight junctions, mirroring early vascular compromise in patients. Complementary work in a transgenic mouse model overexpressing human α-synuclein further confirmed dynamic vascular pathology, with an initial angiogenic response followed by vessel regression and pericyte activation. Together, these models provide mechanistic insight into how mutant proteins and inflammatory glia orchestrate neurovascular unit disruption in Parkinson’s disease.

Neurovascular Mechanisms in Parkinson's Disease publication trend

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

Technical terms

Neurovascular unit: The functional ensemble of brain endothelial cells, pericytes, astrocytes, microglia and extracellular matrix that regulates blood–brain barrier integrity and cerebral perfusion.

Blood–brain barrier (BBB): A selective barrier formed by endothelial tight junctions and supporting cells that controls molecular and cellular traffic between blood and neural tissue.

Pericyte: A contractile cell associated with capillaries, critical for vascular stability, regulation of blood flow and maintenance of barrier properties.

Astrocyte: A glial cell that supports neuronal function, modulates synaptic activity and contributes to blood–brain barrier formation and repair.

Alpha-synuclein: A neuronal protein prone to misfolding and aggregation in Parkinson’s disease, implicated in both neuronal toxicity and vascular dysfunction.

Microglia: The resident immune cells of the brain that respond to injury or pathology by releasing cytokines and matrix remodelling enzymes, influencing neurovascular health.

References

1. The contribution of inflammatory astrocytes to BBB impairments in a brain-chip model of Parkinson’s disease. Nature Communications (2023).
2. Modeling alpha-synuclein pathology in a human brain-chip to assess blood-brain barrier disruption. Nature Communications (2021).
3. Human α-synuclein overexpression in a mouse model of Parkinson’s disease leads to vascular pathology, blood brain barrier leakage and pericyte activation. Scientific Reports (2021).
4. Blood–brain barrier alterations and their impact on Parkinson’s disease pathogenesis and therapy. Translational Neurodegeneration (2024).
5. The link between neuroinflammation and the neurovascular unit in synucleinopathies. Science Advances (2023).