An estrogen conjugate is a conjugate of 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 ...

estrogen Estrogen or oestrogen is a category of sex hormone responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens that have estrogenic hormonal acti ...

. They occur naturally in the body as

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 ...

s of estrogens and can be reconverted back into estrogens. They serve as a circulating reservoir for estrogen, particularly in the case of orally administered

pharmaceutical A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field and re ...

estradiol Estradiol (E2), also spelled oestradiol, is an estrogen steroid hormone and the major female sex hormone. It is involved in the regulation of the estrous and menstrual female reproductive cycles. Estradiol is responsible for the development of f ...

. Estrogen conjugates include

sulfate The sulfate or sulphate ion is a polyatomic anion with the empirical formula . Salts, acid derivatives, and peroxides of sulfate are widely used in industry. Sulfates occur widely in everyday life. Sulfates are salts of sulfuric acid and many ar ...

and/or

glucuronide A glucuronide, also known as glucuronoside, is any substance produced by linking glucuronic acid to another substance via a glycosidic bond. The glucuronides belong to the glycosides. Glucuronidation, the conversion of chemical compounds to glucur ...

conjugates of

estrone Estrone (E1), also spelled oestrone, is a steroid, a weak estrogen, and a minor female sex hormone. It is one of three major endogenous estrogens, the others being estradiol and estriol. Estrone, as well as the other estrogens, are synthesized ...

, and

estriol Estriol (E3), also spelled oestriol, is a steroid, a weak estrogen, and a minor female sex hormone. It is one of three major endogenous estrogens, the others being estradiol and estrone. Levels of estriol in women who are not pregnant are almost ...

: * Sulfated: ** Estrone 3-sulfate (E1S) **

Estradiol 3-sulfate Estradiol sulfate (E2S), or 17β-estradiol 3-sulfate, is a natural, endogenous steroid and an estrogen ester. E2S itself is biologically inactive, but it can be converted by steroid sulfatase (also called estrogen sulfatase) into estradiol, wh ...

(E2S, E2-3S) and

estradiol 17β-sulfate Estradiol 17β-sulfate is an estrogen conjugate which is produced from estradiol by sulfation of the C17β hydroxyl group by estrogen sulfotransferases. See also * Estradiol 3-sulfate Estradiol sulfate (E2S), or 17β-estradiol 3-sulfate, is a ...

(E2-17S) **

Estriol 3-sulfate Estriol sulfate, or estriol 3-sulfate, is a conjugation (biochemistry), conjugated metabolite of estriol that is present in high quantities during pregnancy. It is formed from estriol in the liver and is eventually excretion, excreted in the urine ...

(E3S) **

Estradiol 3,17β-disulfate Estradiol disulfate (also known as E2DS or estradiol 3,17β-disulfate) is an endogenous estrogen conjugate and metabolite of estradiol. It is related to estradiol 3-sulfate and estradiol 17β-sulfate. Estradiol disulfate has 0.0004% of the rela ...

(E2DS) * Glucuronidated: **

Estrone 3-glucuronide Estrone glucuronide, or estrone-3-D-glucuronide, is a conjugated metabolite of estrone. It is formed from estrone in the liver by UDP-glucuronyltransferase via attachment of glucuronic acid and is eventually excreted in the urine by the kidneys ...

(E1-G) **

Estradiol 3-glucuronide Estradiol 3-glucuronide (E2-3G), also known as 17β-estradiol 3-(β-D-glucuronide), is a naturally occurring and endogenous estrogen conjugate. It is specifically the C3 glucuronide conjugate of estradiol, the major estrogen in the body. It is f ...

(E2-3G) and

estradiol 17β-glucuronide Estradiol glucuronide, or estradiol 17β-D-glucuronide, is a conjugated metabolite of estradiol. It is formed from estradiol in the liver by UDP-glucuronyltransferase via attachment of glucuronic acid and is eventually excreted in the urine by ...

(E2-17G) **

Estriol 3-glucuronide Estriol 3-glucuronide, or oestriol 3-glucuronide, also known as estriol 3-β-D-glucosiduronic acid, is a natural, steroidal estrogen and a glucuronic acid (β-D-glucopyranuronic acid) conjugate of estriol. It is found in the urine of women as a ...

(E3-3G),

estriol 16α-glucuronide Estriol glucuronide (E3G), or oestriol glucuronide, also known as estriol monoglucuronide, as well as estriol 16α-β-D-glucosiduronic acid, is a natural product, natural, steroidal estrogen and the glucuronic acid (β-D-glucopyranuronic acid) co ...

(E3-16G) * Mixed: **

Estradiol 3-glucuronide 17β-sulfate Estradiol 3-glucuronide 17β-sulfate (E2-3G-17S) is an endogenous estrogen conjugate and metabolite of estradiol. It is related to estradiol 3-sulfate and estradiol 17β-glucuronide. Estradiol 3-glucuronide 17β-sulfate has 0.0001% of the relat ...

(E2-3G-17βS) **

Estradiol 3-sulfate 17β-glucuronide Estradiol (E2), also spelled oestradiol, is an estrogen steroid hormone and the major female sex hormone. It is involved in the regulation of the estrous and menstrual female reproductive cycles. Estradiol is responsible for the development of ...

(E2-3S-17βG) **

Estriol 3-sulfate 16α-glucuronide Estriol sulfate glucuronide, or estriol 3-sulfate 16α-glucuronide, is an endogenous, naturally occurring diconjugated metabolite of estriol. It is generated in the liver from estriol sulfate by UDP-glucuronyltransferase and is eventually excre ...

(E3-3S-16G) Estrogen conjugates are conjugated at the C3, C16α, and/or C17β positions, where

hydroxyl group In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy g ...

s are available. Estrogen conjugates have been used as

estrogens, as in estrone sulfate as

estropipate Estropipate, also known as piperazine estrone sulfate and sold under the brand names Harmogen, Improvera, Ogen, Ortho-Est, and Sulestrex among others, is an estrogen medication which is used mainly in menopausal hormone therapy in the treatmen ...

(piperazine estrone sulfate) and in

conjugated estrogens Conjugated estrogens (CEs), or conjugated equine estrogens (CEEs), sold under the brand name Premarin among others, is an estrogen (medication), estrogen medication which is used in menopausal hormone therapy and for various other indications. ...

(Premarin) and

conjugated estriol Conjugated estriol, sold under the brand names Progynon and Emmenin, is an estrogen (medication), estrogen medication which was previously used for estrogen-type indications such as the treatment of menopausal symptoms in women. The term specifi ...

(Progynon, Emmenin).

References

{{Estrogen receptor modulators Estranes Estrogens Human metabolites Steroid hormones