Ketosteroid

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Steroid skeleton. Carbons 18 and above can be absent. Trimethyl steroid-nomenclature.png
Steroid skeleton. Carbons 18 and above can be absent.
Androstenedione Androstendion.svg
Androstenedione
Androsterone Androsteron.svg
Androsterone
Estrone Estrone structure.svg
Estrone

A ketosteroid, or an oxosteroid, is a steroid in which a hydrogen atom has been replaced with a ketone (C=O) group.

A 17-ketosteroid is a ketosteroid in which the ketone is located specifically at the C17 position (in the upper right corner of most structure diagrams).

Examples of 17-ketosteroids include:

17-Ketosteroids are endogenous steroid hormones.

See also



Related Research Articles

Oppenauer oxidation, named after Rupert Viktor Oppenauer, is a gentle method for selectively oxidizing secondary alcohols to ketones.

<span class="mw-page-title-main">Trilostane</span> Chemical compound

Trilostane, sold under the brand name Vetoryl among others, is a medication which has been used in the treatment of Cushing's syndrome, Conn's syndrome, and postmenopausal breast cancer in humans. It was withdrawn for use in humans in the United States in the 1990s but was subsequently approved for use in veterinary medicine in the 2000s to treat Cushing's syndrome in dogs. It is taken by mouth.

3β-Hydroxysteroid dehydrogenase/Δ5-4 isomerase (3β-HSD) is an enzyme that catalyzes the biosynthesis of the steroid progesterone from pregnenolone, 17α-hydroxyprogesterone from 17α-hydroxypregnenolone, and androstenedione from dehydroepiandrosterone (DHEA) in the adrenal gland. It is the only enzyme in the adrenal pathway of corticosteroid synthesis that is not a member of the cytochrome P450 family. It is also present in other steroid-producing tissues, including the ovary, testis and placenta. In humans, there are two 3β-HSD isozymes encoded by the HSD3B1 and HSD3B2 genes.

<span class="mw-page-title-main">Hydroxysteroid</span> Class of chemical compounds

A hydroxysteroid is a molecule derived from a steroid with a hydrogen replaced with a hydroxy group. When the hydroxy group is specifically at the C3 position, hydroxysteroids are referred to as sterols, with an example being cholesterol.

<span class="mw-page-title-main">Hydroxysteroid dehydrogenase</span>

Hydroxysteroid dehydrogenases (HSDs) are a group of alcohol oxidoreductases that catalyze the dehydrogenation of hydroxysteroids. These enzymes also catalyze the reverse reaction, acting as ketosteroid reductases (KSRs).

<span class="mw-page-title-main">Androstadienone</span> Chemical compound

Androstadienone, or androsta-4,16-dien-3-one, is a 16-androstene class endogenous steroid that has been described as having potent pheromone-like activities in humans. The compound is synthesized from androstadienol by 3β-hydroxysteroid dehydrogenase, and can be converted into androstenone by 5α-reductase, which can subsequently be converted into 3α-androstenol or 3β-androstenol by 3-ketosteroid reductase.

17β-Hydroxysteroid dehydrogenases, also 17-ketosteroid reductases (17-KSR), are a group of alcohol oxidoreductases which catalyze the reduction of 17-ketosteroids and the dehydrogenation of 17β-hydroxysteroids in steroidogenesis and steroid metabolism. This includes interconversion of DHEA and androstenediol, androstenedione and testosterone, and estrone and estradiol.

<span class="mw-page-title-main">3alpha(or 20beta)-hydroxysteroid dehydrogenase</span> Class of enzymes

In enzymology, a 3alpha(or 20beta)-hydroxysteroid dehydrogenase (EC 1.1.1.53) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">HSD17B1</span> Protein-coding gene in the species Homo sapiens

17β-Hydroxysteroid dehydrogenase 1 (17β-HSD1) is an enzyme that in humans is encoded by the HSD17B1 gene. This enzyme oxidizes or reduces the C17 hydroxy/keto group of androgens and estrogens and hence is able to regulate the potency of these sex steroids

<span class="mw-page-title-main">Steroid Delta-isomerase</span>

In enzymology, a steroid Δ5-isomerase is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">AKR1C3</span> Protein-coding gene in the species Homo sapiens

Aldo-keto reductase family 1 member C3 (AKR1C3), also known as 17β-hydroxysteroid dehydrogenase type 5 is a key steroidogenic enzyme that in humans is encoded by the AKR1C3 gene.

<span class="mw-page-title-main">AKR1C1</span> Protein-coding gene in the species Homo sapiens

Aldo-keto reductase family 1 member C1 also known as 20α-hydroxysteroid dehydrogenase, 3α-hydroxysteroid dehydrogenase, and dihydrodiol dehydrogenase 1/2 is an enzyme that in humans is encoded by the AKR1C1 gene.

<span class="mw-page-title-main">3α-Hydroxysteroid dehydrogenase</span> Protein-coding gene in the species Homo sapiens

3α-Hydroxysteroid dehydrogenase is an enzyme that in humans is encoded by the AKR1C4 gene. It is known to be necessary for the synthesis of the endogenous neurosteroids allopregnanolone, THDOC, and 3α-androstanediol. It is also known to catalyze the reversible conversion of 3α-androstanediol (5α-androstane-3α,17β-diol) to dihydrotestosterone and vice versa.

<span class="mw-page-title-main">HSD17B7</span> Protein-coding gene in the species Homo sapiens

3-keto-steroid reductase is an enzyme that in humans is encoded by the HSD17B7 gene.

<span class="mw-page-title-main">HSD17B3</span> Protein-coding gene in the species Homo sapiens

17β-Hydroxysteroid dehydrogenase 3 (17β-HSD3) is an enzyme that in humans is encoded by the HSD17B3 gene and is involved in androgen steroidogenesis.

<span class="mw-page-title-main">Epiandrosterone</span> Chemical compound

Epiandrosterone, or isoandrosterone, also known as 3β-androsterone, 3β-hydroxy-5α-androstan-17-one, or 5α-androstan-3β-ol-17-one, is a steroid hormone with weak androgenic activity. It is a metabolite of testosterone and dihydrotestosterone (DHT). It was first isolated in 1931, by Adolf Friedrich Johann Butenandt and Kurt Tscherning. They distilled over 17,000 litres of male urine, from which they got 50 milligrams of crystalline androsterone, which was sufficient to find that the chemical formula was very similar to estrone.

Ketosteroid monooxygenase (EC 1.14.13.54, steroid-ketone monooxygenase, progesterone, NADPH2:oxygen oxidoreductase (20-hydroxylating, ester-producing), 17alpha-hydroxyprogesterone, NADPH2:oxygen oxidoreductase (20-hydroxylating, side-chain cleaving), androstenedione, NADPH2:oxygen oxidoreductase (17-hydroxylating, lactonizing)) is an enzyme with systematic name ketosteroid,NADPH:oxygen oxidoreductase (20-hydroxylating, ester-producing/20-hydroxylating, side-chain cleaving/17-hydroxylating, lactonizing). This enzyme catalyses the following chemical reaction

<span class="mw-page-title-main">20α-Dihydroprogesterone</span> Chemical compound

20α-Dihydroprogesterone (20α-DHP), also known as 20α-hydroxyprogesterone (20α-OHP), is a naturally occurring, endogenous progestogen. It is a metabolite of progesterone, formed by the 20α-hydroxysteroid dehydrogenases (20α-HSDs) AKR1C1, AKR1C2, and AKR1C3 and the 17β-hydroxysteroid dehydrogenase (17β-HSD) HSD17B1. 20α-DHP can be transformed back into progesterone by 20α-HSDs and by the 17β-HSD HSD17B2. HSD17B2 is expressed in the human endometrium and cervix among other tissues. In animal studies, 20α-DHP has been found to be selectively taken up into and retained in target tissues such as the uterus, brain, and skeletal muscle.

<span class="mw-page-title-main">AKR1</span>

Aldo-keto reductase family 1 (AKR1) is a family of aldo-keto reductase enzymes that is involved in steroid metabolism. It includes the AKR1C and AKR1D subgroups, which respectively consist of AKR1C1–AKR1C4 and AKR1D1. Together with short-chain dehydrogenase/reductases (SDRs), these enzymes catalyze oxidoreductions, act on the C3, C5, C11, C17 and C20 positions of steroids, and function as 3α-HSDTooltip 3α-Hydroxysteroid dehydrogenases, 3β-HSDsTooltip 3β-Hydroxysteroid dehydrogenases, 5β-reductases, 11β-HSDsTooltip 11β-Hydroxysteroid dehydrogenases, 17β-HSDsTooltip 17β-hydroxysteroid dehydrogenases, and 20α-HSDsTooltip 20α-Hydroxysteroid dehydrogenases, respectively. The AKR1C enzymes act as 3-, 17- and 20-ketosteroid reductases, while AKR1D1 acts as the sole 5β-reductase in humans.

<span class="mw-page-title-main">Steroidogenic enzyme</span>

Steroidogenic enzymes are enzymes that are involved in steroidogenesis and steroid biosynthesis. They are responsible for the biosynthesis of the steroid hormones, including sex steroids and corticosteroids, as well as neurosteroids, from cholesterol. Steroidogenic enzymes are most highly expressed in classical steroidogenic tissues, such as the testis, ovary, and adrenal cortex, but are also present in other tissues in the body.