Chronic Hypertension Impairs Lymphatic Drainage in Deep Cervical Lymph Nodes

Area of Science:

• Neuroscience
• Physiology
• Medical Imaging

Background:

• The glymphatic-meningeal pathway is crucial for brain homeostasis and relies on cervical lymphatic drainage.
• Current therapies targeting this pathway are limited by the lack of methods to quantify lymphatic drainage function.
• Understanding lymphatic drainage is key to developing therapies for brain health.

Purpose of the Study:

• To develop and apply a fluid transport model to DCE-MRI data for quantifying lymphatic drainage through deep cervical lymph nodes (dcLN).
• To investigate the impact of chronic hypertension on dcLN drainage function.
• To establish a link between systemic disease and brain health via impaired lymphatic drainage.

Main Methods:

• Developed a fluid transport model integrating solute transport principles for real-time microflow analysis.
• Applied the model to dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) data.
• Compared lymphatic drainage in normotensive Wistar-Kyoto rats with spontaneously hypertensive stroke-prone (SHRSP) rats.

Main Results:

• The model visualized complex, tortuous lymph streams in normotensive rats.
• SHRSP rats showed significantly altered fluid dynamics with simpler stream patterns and reduced dcLN flow.
• Chronic hypertension was demonstrated to adversely affect lymph node drainage function.

Conclusions:

• Untreated chronic hypertension impairs deep cervical lymph node drainage.
• Impaired lymphatic drainage may be a mechanism linking systemic diseases like hypertension to brain health.
• The developed model offers a novel method for quantifying lymphatic drainage in vivo.