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Cortisone
is one of several end products of a process called steroidogenesis.
This process starts with cholesterol which
then goes through a series of reactions in the adrenal gland to produce a variety of steroid hormones.
One
endproduct of this pathway is cortisol, which is then released from the adrenal gland by ACTH signaling from the anterior
pituitary, which is stimulated by corticotropin-releasing hormone from the hypothalamus in the brain.
In
the peripheral tissues cortisol is converted to cortisone by 11-beta-steroid dehydrogenase.
Cortisol has
much greater glucocorticoid activity than cortisone and thus cortisone can be considered an inactive metabolite of cortisol.
However 11-beta-steroid dehydrogenase can catalyze the reverse reaction as well and thus cortisone is also
the inactive precursor molecule of the active hormone cortisol.
Cortisone is activated through hydroxylation
of the 11-keto-group by an enzyme called 11-beta-steroid dehydrogenase. The active form, cortisol, is thus sometimes referred
to as hydrocortisone.
Effects and uses
Cortisol and adrenaline are the
main hormones released by the body as a reaction to stress.
They elevate blood pressure and prepare the
body for a fight or flight response.
Cortisone is sometimes used as a drug to treat a variety of ailments.
It can be administered intravenously or cutaneously.
One of cortisone's effects on the body, and
a potentially harmful side effect when administered clinically, is the suppression of the immune system.
This
could be the explanation for the apparent correlation between high stress and sickness.
The suppression
of the immune system may be important in the treatment of inflammatory conditions such as severe IgE-mediated
allergies.
Cortisone is less important than a similar steroid cortisol. Cortisol is responsible for 95%
of the effects of the glucocorticosteroids while cortisone is about 4 or 5%. Corticosterone is even less important.
Cortisone shots also may leave "dents" in the injection area, in some cases.
History
Cortisone was first discovered by the
American chemist Edward Calvin Kendall while a researcher at the Mayo Clinic.
He won the 1950 Nobel Prize
for Physiology or Medicine along with Philip S. Hench and Tadeus Reichstein for the discovery of adrenal cortex hormones,
their structures, and functions.
Cortisone was first produced commercially by Merck & Co. under the
leadership of George W. Merck.
