Mechanism for the Success of Sauna Therapy in the Treatment of MCS
A recent paper on sauna therapy by Dr. Martin L. Pall argues for a novel mechanism for its mode of action (1). Pall argues that sauna therapy acts primarily by increasing the availability of a compound called tetrahydrobiopterin (BH4) in the body. BH4 is reported or thought to be depleted in a number of medical conditions that are also reported to respond positively to sauna therapy, including multiple chemical sensitivity, fibromyalgia, chronic fatigue syndrome, hypertension, vascular endothelial dysfunction and heart failure. This pattern of action can be explained, therefore, if sauna therapy increases the availability in the body of BH4.
Pall argues for two distinct mechanisms by which sauna therapy is expected to increase availability of BH4. Both of these act by increasing the synthesis of an enzyme, known as GTP cyclohydolase I, the rate limiting enzyme in the biosynthesis of BH4.
Sauna therapy is known to produce large increases in blood flow in the outer heated parts of the body and the consequent increase in vascular shear stress has been shown to induce large increases in GTP cyclohydrolase I activity and consequent increases in BH4.
A second such mechanism is mediated through the action of the heat shock protein, Hsp90, a protein known to be induced by modest tissue heating and a protein that is recruited into a complex of proteins containing GTP cyclohydrolase I. The Hsp90 protein lowers the proteolytic degradation of GTP cyclohydrolase I protein, leading to increased BH4 synthesis and this has been shown to lower, in turn, the partial uncoupling of the eNOS nitric oxide synthase. Increases in BH4 synthesis in response to both of these two mechanisms may be expected to feed BH4 to various tissues in the body including those not directly impacted by sauna therapy.
The health benefits of vigorous exercise may also be mediated, in part, via these same mechanisms.
A number of additional diseases are reported to involved BH4 depletion including Alzheimer’s, Parkinson’s, asthma, schizophrenia, bipolar disorder, pulmonary hypertension and type 2 diabetes so that each of these may respond to sauna therapy, as well.
It has been commonly assumed that the response of MCS cases to sauna therapy is mediated by a detoxification process known as depuration. There is some published evidence that some increase in detoxification does occur in response to sauna therapy. However the main influence of sauna therapy on MCS cases and certainly in these other medical conditions may well be through increased BH4 availability.
1. Pall ML. 2009 Do sauna therapy and exercise act by raising the availability of tetrahydrobiopterin? Med Hypotheses. 2009 Jul 4. [Epub ahead of print] View Abstract
Related articles:
- New Mechanism Fundamental to the Spread of Invasive Yeast Infections Through Biofilm Formation Identified
- Multiple Chemical Sensitivity – Mechanisms Explained – Free Review
- IBS Guidelines and Online Patient Tools Helpful for Diagnosis, Treatment
- Probiotics – Novel Uses for Clinical Success
- Human T Regulatory Cell Therapy: Take a Billion or So and Call Me in the Morning
If you found this post interesting, please share it, leave a comment or subscribe to the RSS feed and get future posts delivered to your feed reader.
Leave Comment
You can ask technical questions, be as supportive, critical or controversial as you like, but please don't get personal or offensive, and do keep it brief. Your comments will be published only after verification.

The immune system is prone to the same grave misfortunes as any defense system handling weapons: collateral damage that comes with the destruction of the enemy on one’s own territory and friendly fire due to mistaken identity. Whereas the collateral damage is the price we pay for clearance of infections, autoimmunity is a pathological process. Nevertheless, the effector mechanisms involved in both processes are the same. Whether environment can be a cause, a trigger or an amplifier of an autoimmune disease are questions that are being intensively investigated.


