Androstanedione, also known as 5α-androstanedione or as 5α-androstane-3,17-dione, is a
naturally occurring androstane (5α-androstane)
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 an
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 ...
metabolite
In biochemistry, a metabolite is an intermediate or end product of metabolism.
The term is usually used for small molecules. Metabolites have various functions, including fuel, structure, signaling, stimulatory and inhibitory effects on enzymes, c ...
of
androgens like
testosterone,
dihydrotestosterone (DHT),
dehydroepiandrosterone (DHEA), and
androstenedione
Androstenedione, or 4-androstenedione (abbreviated as A4 or Δ4-dione), also known as androst-4-ene-3,17-dione, is an endogenous weak androgen steroid hormone and intermediate in the biosynthesis of estrone and of testosterone from dehydroepia ...
.
It is the C5
epimer of
etiocholanedione (5β-androstanedione).
Androstanedione is formed from androstenedione by
5α-reductase
5α-Reductases, also known as 3-oxo-5α-steroid 4-dehydrogenases, are enzymes involved in steroid metabolism. They participate in three metabolic pathways: bile acid biosynthesis, androgen and estrogen metabolism. There are three isozymes of ...
and from DHT by
17β-hydroxysteroid dehydrogenase
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.
See ...
.
It has some
androgenic activity.
In female genital skin, the conversion of androstenedione into DHT through 5α-androstanedione appears to be more important than the direct conversion of testosterone into DHT.
References
External links
Androstanedione (HMDB0000899) - Human Metabolome Database
5α-Reduced steroid metabolites
Androgens and anabolic steroids
Androstanes
Diketones
Steroid hormones
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