Skin Sodium and Hypertension: a Paradigm Shift?

Area of Science:

• Cardiovascular Physiology
• Renal Physiology
• Dermatology

Background:

• Dietary sodium intake is a key factor in hypertension development.
• Individual blood pressure responses to salt vary significantly.
• The exact mechanisms behind salt sensitivity remain incompletely understood, with a traditional focus on renal sodium handling.

Purpose of the Study:

• To explore the role of the skin in modulating the body's response to dietary sodium.
• To investigate skin sodium storage as a potential factor in blood pressure regulation.
• To examine the relationship between skin sodium, hypertension, and salt sensitivity.

Main Methods:

• Review of animal and human studies on sodium handling and blood pressure.
• Analysis of mechanisms involving skin sodium accumulation (e.g., via glycosaminoglycans).
• Investigation of lymphangiogenesis and vascular endothelial growth factor-C's role in salt response.

Main Results:

• Animal studies suggest salt loading leads to non-osmotic sodium accumulation in the skin.
• Skin sodium accumulation, mediated by factors like glycosaminoglycans and lymphangiogenesis, can attenuate blood pressure rise.
• Human studies indicate the skin acts as a sodium buffer, with skin sodium levels correlating with hypertension and salt sensitivity.

Conclusions:

• The skin represents a significant, previously underappreciated, reservoir for sodium.
• Skin sodium storage may be a critical determinant of individual blood pressure variability in response to salt intake.
• Understanding skin sodium dynamics offers new insights into hypertension and salt sensitivity mechanisms.