Does sensitivity to the stress hormone cortisol have a connection to diseases such as obesity and depression?
Obesity is a worldwide problem and is particularly prevalent in the United States where over 40% of the US has obesity and deaths from obesity and its complications are estimated to be over 300,000 people per year. Understanding the causes of obesity may help scientists develop new treatments. For some people the stress hormone cortisol may be a part of the problem.
Cortisol is a hormone that helps your body respond to stress. When you are stressed the hypothalamus in the brain sends a signal to the pituitary gland (corticotropin releasing hormone) which causes the pituitary to release another hormone called corticotropin or ACTH. ACTH stimulates the adrenal glands to produce cortisol as shown in figure 1 (reprinted from “Hypothalamic-Pituitary-Adrenal Axis”, by BioRender, November 2019, retrieved from https://bit.ly/2MwB70R Copyright 2021 by BioRender).
Cortisol has multiple effects on the body to help you cope with stress: it raises your blood pressure and blood sugar, decreases REM sleep, and increases your appetite. Although these are normal responses to cortisol, when too much cortisol is produced it causes these (and other) effects of cortisol to be amplified in unhealthy ways causing diseases such as obesity, type 2 diabetes, high blood pressure, and depression. Cortisol also acts as an anti-inflammatory (anyone who has had a cortisone shot has experienced this effect first-hand).
Most people with obesity do not have elevated cortisol. Our lab and others have hypothesized that it could be the case that some people are hypersensitive to normal cortisol levels. Think about how some people are more sensitive to sound or light- it’s the same idea but with elevated response to cortisol.
Why might some people have increased responsiveness to cortisol? It could be because of genetic differences. We are looking to see if there is a correlation between obesity and single nucleotide polymorphisms (natural variations in the DNA sequence) of genes related to the actions of cortisol. We are also investigating possible connections to obesity-related comorbidities such as elevated blood sugar, blood pressure, increased waist/hip circumference ratio, and altered serum lipid profiles. We are fortunate to have a collaboration with the Ellis Hospital Bariatric Medicine group and fantastic patients who have agreed to be a part of our study.
Interestingly, diseases with high cortisol and diseases with low cortisol are associated with depression. This made us wonder if similar single nucleotide polymorphisms might be associated with depression. We currently have a collaboration with the Psychiatry Clinic at Albany Medical College to ask these questions as well as a collaboration with the Wicker Wellness Center at Union College to ask these questions in a college population of patients with depression.
You must be logged in to post a comment.