Who has never caught a cold after being exposed to a strong storm? Or fell ill after that rush of thesis delivery, or even after months of preparing for that much-anticipated event? Nowadays, we often say that stress is to blame for everything, or at least it haunts our routine. But should we always crucify it this way? Is there such a thing as positive stress? What is the impact of this 21st-century symptom on our immune system and our network of neural connections?
Stress is known for allowing the fight or flight response, an important survival mechanism for living beings. In our body, the response to stress triggers the release of neurotransmitters, hormones, peptides, and cytokines that act on almost all cells and tissues through circulation, informing the presence of the stressor.
Stress has a significant and direct action on the immune system, potentially even suppressing a person's immune response, increasing their susceptibility to infections and even to the development of cancer. On the other hand, in addition to favoring a state of immunosuppression, stress can also contribute to a more exacerbated response of asthma, allergies, and inflammatory autoimmune diseases. Thus, a beneficial or harmful consequence triggered by stress depends on the type of immune response that will be stimulated [1].
Studies show that several factors are important in determining the protective or harmful effect of stress and its hormones on the immune system, such as the duration of the stimulus, the intensity, and the distribution of leukocytes throughout the body. Acute stress, lasting from minutes to hours, induces a redistribution of leukocytes to the skin and activates both the innate and adaptive responses that can quickly act against an infection, for example, as well as inducing a more efficient response to a vaccine. Conversely, it can exacerbate an allergic response if it occurs during a crisis. Chronic stress, which can persist for days or even months, induces a completely different response: it alters the cytokine balance from a Th1 (pro-inflammatory) pattern to a Th2 (anti-inflammatory) pattern, an immunoregulatory response that can contribute to the control of autoimmune diseases, but on the other hand, it can decrease resistance to infections and cancer [1].
I imagine that some questions may have arisen at this point in the reading, such as: since various paths can be taken by our body in a stressful situation, can I "decide" or help it take the best path? The answer is yes!
By understanding how the immune system, responsible for defense and daily maintenance of homeostasis, can be affected by psychological stress, we can now help it react in the best possible way in maintaining balance.
A practice that we all know is good for health is regular physical activity. But perhaps few know that this effect is due to its anti-inflammatory activity. Several mechanisms are of great importance in this context of high glycogen demand, such as: increased release of cortisol and adrenaline by the adrenal glands, increased IL-6 cytokine, which is considered both pro and anti-inflammatory, but is capable of inducing the synthesis of anti-inflammatory factors in addition to decreasing circulating pro-inflammatory monocytes. This shows us the important role of physical exercise that we can include in our daily routine to maintain our body's health, even preventing chronic metabolic and cardiorespiratory diseases [2].
Thus, since the reactions between the immune system and the central nervous system are directly integrated, to combat this stress, we can invest in some activities such as social interaction programs, physical activity, relaxation, and yoga, among other activities that give meaning and value to our lives. They will certainly impact the health of your immune system and consequently your health.
Therefore, de-stress your immune system. Accept, forgive, feel, appreciate, beautify yourself, exercise, feel good, interact, and live!
Consulted and Suggested Bibliographic References
[1] Dhabhar FS. Enhancing versus suppressive effects of stress on immune function: implications for immunoprotection and immunopathology. Neuroimmunomodulation. 2009;16(5):300-17. doi: 10.1159/000216188. Epub 2009 Jun 29.
[2] Gleeson M, Bishop NC, Stensel DJ, Lindley MR, Mastana SS, Nimmo MA. The anti-inflammatory effects of exercise: mechanisms and implications for the prevention and treatment of disease. Nat Rev Immunol. 2011 Aug 5;11(9):607-15. doi: 10.1038/nri3041.
McEwen BS. Brain on stress: how the social environment gets under the skin. Proc Natl Acad Sci U S A. 2012 Oct 16;109 Suppl 2:17180-5. doi: 10.1073/pnas.1121254109. Epub 2012 Oct 8.
