Podcast

Cortisol Podcast

https://sites.google.com/site/chrishbiology/

Transcript:
Today, I will be explaining the hormone Cortisol in as little time as possible. I'm Chris, and this is Jugo's Podcast. (Intro Music: Happy Families - Sam Fonteyn)

Cortisol is widely considered the "stress hormone." It regulates glucose levels, blood pressure, blood vessel tone and contraction, and nervous system activation. Also, it prevents the release of substances that cause inflammation and acts as an anti-inflammatory. However, the main function is to stimulate gluconeogenesis, or the formation of glucose from amino acids, glycerol, lactate, and propionate. This formation of glucose keeps the body alive during times of stress, ergo, the "stress hormone."

When Cortisol is released at normal levels, the body functions just fine. However, an over or under release of Cortisol can cause negative effects. High levels of Cortisol can lead to many symptoms, including blood sugar imbalance, disruption of sleep, lowered immune system function, impaired cognitive function, decreased bone function, decreased muscle mass, elevated blood pressure, slow wound healing, and increased abdominal fat. On the other hand, low levels of Cortisol can cause blood sugar imbalance, disruption of sleep, lowered immune system function, brain foggy or light-headedness, mild depression, low thyroid function, lowered blood pressure, fatigue, and increased inflammation. So, on that note, it's pretty important to have normal levels of Cortisol.

Cortisol, or C21H30O5, is a steroid hormone that is synthesized from cholesterol. This type of hormone is made from cholesterol, as opposed to the amino acid derivates or other peptide hormones which are made of amino acids. Steroid hormones are also soluble in water and lipids.

Production and regulation of this hormone is accomplished via the Hypothalamic-Pituitary-Adrenal Axis, or HPA Axis. Production begins in the Hypothalamus, or a small gland within the brain that is part of the endocrine system. When the body experiences increased stress, physical activity, illness, high blood levels of Cortisol, or a differentiated sleep/wake cycle*, the Hypothalamus releases "Corticotropin-releasing Hormone", or CRH.

This CRH is then transferred to the Anterior Pituitary Gland, another small part of the brain that is part of the endocrine system. The CRH then stimulates the secretion of "Adrenocorticotropic Hormone", or ACTH, into the vascular system.

This ACTH is then carried via the blood to the Adrenal Cortex, where most (all) of the Cortisol production occurs. The Adrenal Cortex is responsible for the rapid biosynthesis of Cortisol and other corticosteroids from cholesterol, and produces Cortisol in response to the ATCH stimulation. It then acts back on the Hypothalamus and Pituitary Glands to suppress the production of CRH and ACTH via a negative feedback system. The Adrenal Cortex is located along the perimeter of the Adrenal Gland, which rests atop the kidneys.

Being a steroid hormone, Cortisol is soluble in many substances, including water, lipids, ethanol, methanol, and acetone. The cellular receptor for Cortisol is a Glucocorticoid Receptor, or NR3C1 or GCR. It is a receptor to which Cortisol and other Glucocorticoids bind. GCR's are found in almost every cell, and regulate genes controlling the development, metabolism, and immune response. These unbound receptors reside in the cytosol. Once bound, they either upregulate the anti-inflammatory proteins, or they suppress the pro-inflammatory proteins.

Thank you for listening, please tune in next week for more hormone discussion. (Outro Music: Blues in a Hurry- Cecil Norman)