How stress influences disease: Research reveals inflammation as the culprit

Stress wreaks havoc on the mind and body. For example, psychological stress is associated with greater risk for depression, heart disease and infectious diseases. But, until now, it has not been clear exactly how stress influences disease and health.

A research team led by Carnegie Mellon University's Sheldon Cohen has found that chronic psychological stress is associated with the body losing its ability to regulate the . Published in the , the research shows for the first time that the effects of psychological stress on the body's ability to regulate can promote the development and progression of disease.

"Inflammation is partly regulated by the and when cortisol is not allowed to serve this function, inflammation can get out of control," said Cohen, the Robert E. Doherty Professor of Psychology within CMU's Dietrich College of Humanities and Social Sciences.

Cohen argued that prolonged stress alters the effectiveness of cortisol to regulate the inflammatory response because it decreases tissue sensitivity to the hormone. Specifically, immune cells become insensitive to cortisol's regulatory effect. In turn, runaway inflammation is thought to promote the development and progression of many diseases.

Cohen, whose groundbreaking early work showed that people suffering from are more susceptible to developing common colds, used the common cold as the model for testing his theory. With the common cold, symptoms are not caused by the virus — they are instead a "side effect" of the inflammatory response that is triggered as part of the body's effort to fight infection. The greater the body's inflammatory response to the virus, the greater is the likelihood of experiencing the symptoms of a cold.

In Cohen's first study, after completing an intensive stress interview, 276 healthy adults were exposed to a virus that causes the common cold and monitored in quarantine for five days for signs of infection and illness. Here, Cohen found that experiencing a prolonged stressful event was associated with the inability of to respond to hormonal signals that normally regulate inflammation. In turn, those with the inability to regulate the inflammatory response were more likely to develop colds when exposed to the virus.

In the second study, 79 healthy participants were assessed for their ability to regulate the inflammatory response and then exposed to a cold virus and monitored for the production of pro-inflammatory cytokines, the chemical messengers that trigger inflammation. He found that those who were less able to regulate the inflammatory response as assessed before being exposed to the virus produced more of these inflammation-inducing chemical messengers when they were infected.

"The immune system's ability to regulate inflammation predicts who will develop a cold, but more importantly it provides an explanation of how stress can promote disease," Cohen said. "When under stress, cells of the immune system are unable to respond to hormonal control, and consequently, produce levels of inflammation that promote disease. Because inflammation plays a role in many diseases such as cardiovascular, asthma and autoimmune disorders, this model suggests why stress impacts them as well."

He added, "Knowing this is important for identifying which diseases may be influenced by and for preventing disease in chronically stressed people."

More information: “Chronic stress, glucocorticoid receptor resistance, inflammation, and disease risk,” by Sheldon Cohen et al. PNAS, 2012.

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Argiod
not rated yet Apr 02, 2012
"...chronic psychological stress is associated with the body losing its ability to regulate the inflammatory response..."

Gee, I knew that back in the late 50's. My mother had arthritis pretty bad, and any time she was under stress, it flared up and put her into great pain. I'm surprised the medical community is just now discovering this.
210
not rated yet Apr 02, 2012
"
Gee, I knew that back in the late 50's. My mother had arthritis pretty bad, and any time she was under stress, it flared up and put her into great pain. I'm surprised the medical community is just now discovering this.


They are not discovering the fact of the occurance, but, the mechanisms that promote this kind of response and the factors that aggravate at the molecular level.

word-
A2G
not rated yet Apr 02, 2012
"They are not discovering the fact of the occurance, but, the mechanisms that promote this kind of response and the factors that aggravate at the molecular level."

really? The molecular level? I just don't see that in this study.

Cellular level I could buy though.
Lucia-Chupetes con nombre
not rated yet Apr 03, 2012
High psychological stress can make us sick, so is a very important factor to take into account...
No stress!
TheHungerSite_com
not rated yet Apr 03, 2012
Proverbs 16:24
Pleasant words are as an honeycomb, sweet to the soul, and health to the bones.

Proverbs 17:22
A merry heart doeth good like a medicine: but a broken spirit drieth the bones.

Proverbs 15:13
A merry heart maketh a cheerful countenance: but by sorrow of the heart the spirit is broken.

Proverbs 12:25
Heaviness in the heart of man maketh it stoop: but a good word maketh it glad.

Proverbs 18:14
The spirit of a man will sustain his infirmity; but a wounded spirit who can bear?

Proverbs 14:30
A sound heart is the life of the flesh: but envy the rottenness of the bones.

Proverbs 12:4
A virtuous woman is a crown to her husband: but she that maketh ashamed is as rottenness in his bones.

Proverbs 3:
7Be not wise in thine own eyes: fear the LORD, and depart from evil.
8It shall be health to thy navel, and marrow to thy bones.

Proverbs 4:
7Wisdom is the principal thing; therefore get wisdom: and with all thy getting get understanding.
22For they are life unto those that find