The Anti-Inflammatory Effects of Cortisol
Cortisol is a powerful anti-inflammatory, even when secreted at normal levels. It acts quickly to remove and prevent redness and swelling of nearly all tissues. These anti-inflammatory actions keep mosquito bites from flaring into giant lumps, bronchial tubes and eyes from swelling shut from allergens, and mild scratches from looking like you have just had a close call with a mountain lion.
Cortisol maintains the balance through the unwritten law that “for any physical body to remain in homeostatic equilibrium every inflammatory reaction must have an opposite and equal anti-inflammatory reaction.” Although there are other anti-inflammatory responses occurring at local sites, cortisol is the main anti-inflammatory agent circulating naturally in your body. You can assume that almost any time you have an inappropriate amount of redness and/or swelling, there is too little cortisol in circulation.
Cortisol has similar anti-inflammatory control over auto-immune reactions. In auto-immune reactions, white blood cells attack parts of your body as if they were the enemy. These reactions can range from mild to life threatening. In most auto-immune reactions, cortisol levels are inadequate for the degree of reaction taking place in particular tissues or locations in the body.
This is one of the reasons why strong corticosteroids (prednisone, prednisolone, etc.) are used with all diseases involving inflammatory processes, including auto-immune diseases. These hormones imitate the anti-inflammatory effects of cortisol, although often with serious undesirable side effects. Cortisol not only affects the redness and swelling but also the actions of the white blood cells, as described in the next section.
The Effects of Cortisol on White Blood Cells
Cortisol influences most cells that participate in immune reactions and/or inflammatory reactions, especially white blood cells. It specifically regulates lymphocytes, the commanders of the white blood cells. Cortisol and corticoids (cortisol like substances) also affect the actions of other white blood cells with names such as natural killer (NK) cells, monocytes, macrophages, eosinophils, neutrophils, mast cells and basophils. These white blood cells gather in defense of the body at places of injury or perceived invasion and some flood the area with very powerful chemicals to attack the invaders.
Although they are a great defense, these chemicals irritate the surrounding tissues, causing redness and swelling. Cortisol reacts like a crew of firefighters, rushing to the site to put out the fire made by the lymphocytes and other white blood cells. It keeps the local white blood cells from sticking to the site and releasing their chemicals and also controls the number of circulating lymphocytes and other white blood cells, so there are fewer white blood cells available. This prevents an overreaction by the immune system and controls the irritation and tissue destruction that takes place at the site of congregating white blood cells.
Cortisol also reduces the rate at which lymphocytes multiply and accelerates their programmed cell death to further protect the body from this overreaction. In fact, when cortisol is elevated during the alarm reaction, there is almost a complete disappearance of lymphocytes from the blood. That is why your immune system is suppressed when you are under stress or taking corticosteroids. On the other hand, when circulating cortisol is low its moderating effect on immune reactions is lost and lymphocytes circulate in excess. In this situation inflammation is greater with more redness and swelling, and it takes a longer time for the inflamed tissue to return to normal. So, directly and indirectly cortisol dramatically influences most aspects of immune function.
About the Author: With a researcher’s grasp of science and a clinician’s understanding of its human impact, Dr. Wilson has helped many physicians understand the physiology behind and treatment of various health conditions. He is acknowledged as an expert on alternative medicine, especially in the area of stress and adrenal function. Dr. Wilson is a respected and sought after lecturer and consultant in the medical and alternative healthcare communities in the United States and abroad. His popular book Adrenal Fatigue: The 21st Century Stress Syndrome has been received enthusiastically by physicians and the public alike, and has sold over 400,000 copies. Dr. Wilson resides with his family in sunny Tucson, Arizona.
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