The Lymph-Brain Connection
Discoveries made in the past decade enlighten us on the importance of the ability for the brain to clear itself of waste material. Both cerebrospinal fluid (CSF) and interstitial fluid (ISF) drain partly or wholly to regional lymph nodes. Lymphatic drainage of the central nervous system (CNS) has implications for neuroimmunology and homeostasis of the neuronal environment in the brain.
While CSF drains to lymph nodes mainly via lymphatics in the nasal mucosa, lymphatic drainage of ISF and solutes from the brain is along perivascular routes via the carotid and vertebral arteries. Vessels stiffen with age, reducing the arterial pulse that propels CSF and ISF (found in grey and white matter). Failure of lymphatic drainage of the brain is a significant factor in the pathogenesis of Alzheimer’s disease and other dementias.
Astrocytes are a type of glial cell supporting the management of the brain matrix and neurons in the nervous system. Astrocytes are star-shaped cells in the brain that wrap around arteries and veins and transfer molecules and fluids faster and more efficiently than diffusion. The function of the astrocyte, to control chemical composition of fluid surrounding the neurons, is named “glymphatic system”.
Clearance of amyloid betas was about 30 percent slower with Alzheimer’s patients, and there is speculation that the disruptions in the glymphatic system may lead to harmful waste buildup in the brain, damaging cells. Low cell turnover capacity may contribute to cellular susceptibility to toxic proteins.
Arterial pulsations help propel CSF and ISF. Each day, about a pint of CSF is filtered from the blood in the four ventricles in the brain. Most of the fluid is reabsorbed via the lymphatic system before returning to the bloodstream. Astrocytes help dissolve proteins by engulfing them before returning to the bloodstream via the glymphatic system. Manual lymphatic drainage pumps the lymph nodes along the neck region and sinuses, helping to clear the solutes and fluids from the brain.
Susan Couture, BSHA, CRC, LMT. LE, is a Certified MLD/CDP at OM Oracle Massage Lymphatic Therapy, located at 6818 N. Oracle Rd., Ste. 414, Tucson. Connect at 520-668-8731 or OracleMassage.com. See ad, page 32.