Glymphatics in neurovascular diseases

Area of Science:

• Neuroscience
• Vascular Biology
• Waste Clearance Mechanisms

Background:

• The glymphatic system is a brain-wide pathway for waste clearance, crucial for central nervous system (CNS) homeostasis.
• It facilitates nutrient delivery, waste removal, and maintains the ionic microenvironment.
• Glymphatic system dysfunction is linked to neurodegenerative disorders, with emerging neurovascular implications.

Purpose of the Study:

• To review the role of the glymphatic system in neurovascular diseases.
• To highlight how glymphatic system impairments contribute to conditions like subarachnoid hemorrhage and idiopathic intracranial hypertension.
• To explore potential endovascular strategies for mitigating cognitive impairment caused by glymphatic dysfunction.

Main Methods:

• Review of existing literature on glymphatic system function and dysfunction.
• Analysis of mechanisms by which neurovascular diseases impact glymphatic flow, including altered pulsatility and aquaporin-4 malfunction.
• Examination of the link between impaired glymphatic clearance and waste accumulation.

Main Results:

• Glymphatic system function is driven by arterial pulsatility, promoting cerebrospinal fluid (CSF) influx and waste removal via perivascular and perivenous spaces.
• Dysfunction in conditions like subarachnoid hemorrhage, idiopathic intracranial hypertension, and arteriovenous shunting disorders disrupts glymphatic flow.
• Impaired glymphatic clearance leads to the accumulation of waste products, contributing to progressive cognitive decline.

Conclusions:

• The glymphatic system plays a critical role in maintaining CNS health and its dysfunction is implicated in various neurovascular diseases.
• Disruptions in glymphatic flow can result from altered pulsatility, impaired CSF influx, aquaporin-4 malfunction, or venous hypertension.
• Targeted interventions, including potential endovascular approaches, may reverse cognitive impairment associated with glymphatic system dysfunction.