Popular tips

What does 11 beta hydroxysteroid dehydrogenase do?

What does 11 beta hydroxysteroid dehydrogenase do?

11 beta-HSD2 is a high affinity NAD-dependent dehydrogenase that protects the mineralocorticoid receptor from glucocorticoid excess; mutations in the HSD11B2 gene explain an inherited form of hypertension, the syndrome of apparent mineralocorticoid excess in which cortisol acts as a potent mineralocorticoid.

What is the HSD enzyme?

3βHSD1 is an enzyme mainly located in peripheral tissues which metabolizes DHEA to androstenedione, and thus provides a route to DHT synthesis from adrenal precursor steroids (Figure 1).

What enzyme converts cortisone to cortisol?

The enzyme 11-beta-hydroxysteroid dehydrogenase (EC 1.1. 1.146) converts active cortisol into inactive cortisone. The HSD11B2 gene (OMIM 614232) encodes the isoenzyme that is expressed in the kidney and which plays a particularly important role in blood pressure regulation.

How does congenital adrenal hyperplasia cause hypertension?

11β-OH CAH results in hypertension due to excessive mineralocorticoid effects. It also causes excessive androgen production both before and after birth and can virilize a genetically female fetus or a child of either sex.

What is AME disease?

The syndrome of apparent mineralocorticoid excess (AME) is an autosomal recessive disorder characterized by hypertension, hypokalemia, low renin, and hypoaldosteronism. It is caused by deficiency of 11β-hydroxysteroid dehydrogenase, which results in a defect of the peripheral metabolism of cortisol to cortisone.

What is the hormone that burns fat?

Leptin is a hormone released by fat cells. It helps regulate how many calories you burn and how much you eat, which in turn regulates how much fat tissue your body stores.

Do corticosteroids increase cortisol?

Corticosteroid medications used to treat asthma, arthritis, certain cancers, and other conditions can also cause high cortisol levels when taken in high doses or for a long period of time.

How is cortisol metabolised?

Hepatic — The major site of cortisol metabolism is the liver. There, cortisol is reduced, oxidized, or hydroxylated, and the products of these reactions are made water soluble by conjugation with sulfate or glucuronic acid to facilitate their excretion in urine (figure 1).

Is congenital adrenal hyperplasia life threatening?

People who have classic CAH are at risk of adrenal crisis because they have very low levels of cortisol in the blood. This can cause diarrhea, vomiting, dehydration, low blood sugar levels and shock. Adrenal crisis is a life-threatening medical emergency that requires immediate treatment.

Can congenital adrenal hyperplasia cause hypokalemia?

Congenital adrenal hyperplasia due to enzymatic defects is a genetic syndrome strongly associated with hypertension and hypokalemia, resulting from excessive mineralocorticoid effects. Drugs, such as diuretics and penicillin can be often the underlying cause of hypokalemia.

How do you treat AME?

The treatment of AME is primarily directed at the correction of hypokalemia and hypertension. Spironolactone, an MR receptor antagonist, is the medication of choice. Addition of potassium-sparing diuretics may be beneficial, but patients can become refractory to therapy.