noun, plural: glucocorticoids
Corticosteroids belong to a group of steroid hormones that are produced naturally in the adrenal cortex by steroidogenesis in response to the release of adrenocorticotrophin or adrenocorticotropic hormone from the pituitary gland. Corticosteroids may be classified into two major groups based on their predominant biological activity: (1) glucocorticoids and (2) mineralocorticoids.
A glucocorticoid is a substance (a drug or a hormone) involved in the carbohydrate metabolism. For instance, it promotes gluconeogenesis, i.e. the metabolic process in which glucose is formed from non-carbohydrate precursors. It enhances the expression of enzymes essential in gluconeogenesis.
The glucocorticoid is also involved in liver glycogen deposition and in the elevation of blood sugar. Apart from carbohydrates, it has also been found to have a role in fat and protein metabolism. It is involved as well in the maintenance of arterial blood pressure, and alteration of the connective tissue response to injury. It also possesses anti-inflammatory and immunosuppressive properties. For instance, it reduces the number of circulating lymphocytes.
Glucocorticoids are produced mainly in the zona fasciculate of the adrenal cortex, especially in response to stress. They are released into the bloodstream to reach target cells. They exert their action to the cell by binding to the glucocorticoid receptor. The complex leads to the up-regulation of the expression of anti-inflammatory proteins and the down-regulation of the expression of pro-inflammatory proteins.
Synthetic glucocorticoids are used in medicine as a treatment for glucocorticoid deficiency and for suppressing overactive immune system. Possible side effects though are delayed wound healing, muscle weakness, increased risk of infection, suppression of calcium absorption, and inhibition of bone formation.
Word origin: a portmanteau of glu(cose), cort(ex), and (ster)oid