11β-Hydroxyprogesterone (11β-OHP), also known as 21-deoxycorticosterone, as well as 11β-hydroxypregn-4-ene-3,20-dione, is a

naturally occurring A natural product is a natural compound or substance produced by a living organism—that is, found in nature. In the broadest sense, natural products include any substance produced by life. Natural products can also be prepared by chemical synt ...

endogenous Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell. In contrast, exogenous substances and processes are those that originate from outside of an organism. For example, es ...

steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...

and

derivative In mathematics, the derivative of a function of a real variable measures the sensitivity to change of the function value (output value) with respect to a change in its argument (input value). Derivatives are a fundamental tool of calculus. F ...

progesterone Progesterone (P4) is an endogenous steroid and progestogen sex hormone involved in the menstrual cycle, pregnancy, and embryogenesis of humans and other species. It belongs to a group of steroid hormones called the progestogens and is the m ...

. It is a potent

mineralocorticoid Mineralocorticoids are a class of corticosteroids, which in turn are a class of steroid hormones. Mineralocorticoids are produced in the adrenal cortex and influence salt and water balances (electrolyte balance and fluid balance). The primary mi ...

. Syntheses of 11β-OHP from progesterone is catalyzed by the

steroid 11β-hydroxylase Steroid 11β-hydroxylase, also known as steroid 11β-monooxygenase, is a steroid hydroxylase found in the zona glomerulosa and zona fasciculata of the adrenal cortex. Named officially the cytochrome P450 11B1, mitochondrial, it is a protein that ...

(CYP11B1) enzyme, and, to a lesser extent, by the

aldosterone synthase Aldosterone synthase, also called steroid 18-hydroxylase, corticosterone 18-monooxygenase or P450C18, is a steroid hydroxylase cytochrome P450 enzyme involved in the biosynthesis of the mineralocorticoid aldosterone and other steroids. The enzyme ...

enzyme (CYP11B2).

Function

Along with its

epimer In stereochemistry, an epimer is one of a pair of diastereomers. The two epimers have opposite configuration at only one stereogenic center out of at least two. All other stereogenic centers in the molecules are the same in each. Epimerization is ...

11α-hydroxyprogesterone (11α-OHP), 11β-OHP has been identified as a very potent

competitive Competition is a rivalry where two or more parties strive for a common goal which cannot be shared: where one's gain is the other's loss (an example of which is a zero-sum game). Competition can arise between entities such as organisms, indivi ...

inhibitor Inhibitor or inhibition may refer to: In biology * Enzyme inhibitor, a substance that binds to an enzyme and decreases the enzyme's activity * Reuptake inhibitor, a substance that increases neurotransmission by blocking the reuptake of a neurotra ...

of both

isoform A protein isoform, or "protein variant", is a member of a set of highly similar proteins that originate from a single gene or gene family and are the result of genetic differences. While many perform the same or similar biological roles, some isof ...

s ( 1 and 2) of 11β-hydroxysteroid dehydrogenase (11β-HSD).

Outcome of 21-hydroxylase deficiency

It has been known since 1987 that increased levels of 11β-OHP occur in

21-hydroxylase deficiency Congenital adrenal hyperplasia due to 21-hydroxylase deficiency, in all its forms, accounts for over 95% of diagnosed cases of congenital adrenal hyperplasia (CAH), and CAH in most contexts refers to 21-hydroxylase deficiency and different mutat ...

. A study in 2017 has shown that in subjects with 21-hydroxylase deficiency, serum 11β-OHP concentrations range from 0.012 to 3.37 ng/mL, while in control group it was below detection limit of 0.012 ng/mL. 21-hydroxylase is an enzyme that is also involved in progesterone metabolism, producing

11-deoxycorticosterone 11-Deoxycorticosterone (DOC), or simply deoxycorticosterone, also known as 21-hydroxyprogesterone, as well as desoxycortone (INN), deoxycortone, and cortexone, is a steroid hormone produced by the adrenal gland that possesses mineralocorticoid ac ...

. In normal conditions, 21-hydroxylase has higher activity on progesterone than

(CYP11B1) and

(CYP11B2) that convert progesterone to 11β-OHP. That's why in 21-hydroxylase deficiency, given the normal function of the CYP11B enzymes, the progesterone is directed towards 11β-OHP pathway rather than towards 11-deoxycorticosterone pathway, that is also usually accompanied by an increase in progesterone levels. In the normal route to aldosterone and cortisol, progesterone and

17α-hydroxyprogesterone 17α-Hydroxyprogesterone (17α-OHP), also known as 17-OH progesterone (17-OHP), or hydroxyprogesterone (OHP), is an endogenous progestogen steroid hormone related to progesterone. It is also a chemical intermediate in the biosynthesis of many ot ...

are first hydroxylated at position 21 and then hydroxylated at other positions. In 21-hydroxylase deficiency, progesterone and 17α-hydroxyprogesterone accumulate and are the substrates of

, leading to 1β-OHP and 21-deoxycortisol, respectively. In the 2017 study above mentioned, serum progesterone concentrations in boys (10 days to 18 years old) with 21-hydroxylase deficiency reached levels similar to female luteal values (up to 10.14 ng/mL, depending on severity and treatment), while in the control group of boys progesterone was 0.07 ng/mL (0.22 nmol/L) on average, ranged from 0.05 to 0.40 ng/mL. While studies suggest that 11β-OHP, also known as 21-deoxycorticosterone, can be used as marker for adrenal 21-hydroxylase deficiency, another 21-carbon steroid — 21-deoxycortisol (produced from

) gained acceptance for this purpose.

References

External links

Metabocard for 11β-Hydroxyprogesterone (HMDB04031) - Human Metabolome Database
11β-Hydroxysteroid dehydrogenase inhibitors Cyclohexanols Diketones Human metabolites Mineralocorticoids Pregnanes Enones {{steroid-stub

Function

Outcome of 21-hydroxylase deficiency

See also

References

External links