Sex hormone-binding globulin

Last updated
SHBG
1d2s SHBG.png
Available structures
PDB Ortholog search: PDBe RCSB
Identifiers
Aliases SHBG , ABP, SBP, TEBG, sex hormone binding globulin, Sex hormone-binding globulin
External IDs OMIM: 182205 MGI: 98295 HomoloGene: 813 GeneCards: SHBG
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_011367

RefSeq (protein)

NP_035497

Location (UCSC) Chr 17: 7.61 – 7.63 Mb Chr 11: 69.51 – 69.51 Mb
PubMed search [3] [4]
Wikidata
View/Edit Human View/Edit Mouse
Androgen-binding protein, Sex hormone-binding globulin
Identifiers
SymbolSHBG
Alt. symbolsABP
NCBI gene 6462
HGNC 10839
OMIM 182205
RefSeq NM_001040
UniProt P04278
Other data
Locus Chr. 17 p13-p12
Search for
Structures Swiss-model
Domains InterPro

Sex hormone-binding globulin (SHBG) or sex steroid-binding globulin (SSBG) is a glycoprotein that binds to androgens and estrogens. When produced by the Sertoli cells in the seminiferous tubules of the testis, it is called androgen-binding protein (ABP). [5] [6]

Other steroid hormones such as progesterone, cortisol, and other corticosteroids are bound by transcortin. SHBG is found in all vertebrates apart from birds. [7]

Function

Testosterone and estradiol circulate in the bloodstream, loosely bound mostly to serum albumin (~54%), and to a lesser extent bound tightly to SHBG (~44%). Only a very small fraction of about 1 to 2% is unbound, or "free," and thus biologically active and able to enter a cell and activate its receptor. SHBG inhibits the function of these hormones. Thus, the local bioavailability of sex hormones is influenced by the level of SHBG. Because SHBG binds to testosterone (T) and dihydrotestosterone (DHT), these hormones are made less lipophilic and become concentrated within the luminal fluid of the seminiferous tubules. The higher levels of these hormones enable spermatogenesis in the seminiferous tubules and sperm maturation in the epididymis. SHBG’s production is regulated under the influence of FSH [6] on Sertoli cells, enhanced by insulin, retinol, and testosterone.

The relative binding affinity of various sex steroids for SHBG is dihydrotestosterone (DHT) > testosterone > androstenediol > estradiol > estrone. [8] DHT binds to SHBG with about 5 times the affinity of testosterone and about 20 times the affinity of estradiol. [9] Dehydroepiandrosterone (DHEA) is weakly bound to SHBG, but dehydroepiandrosterone sulfate is not bound to SHBG. [8] Androstenedione is not bound to SHBG either, and is instead bound solely to albumin. [10] Estrone sulfate and estriol are also poorly bound by SHBG. [11] Less than 1% of progesterone is bound to SHBG. [12]

SHBG levels are usually about twice as high in women than in men. [9] In women, SHBG serves to limit exposure to both androgens and estrogens. [9] Low SHBG levels in women have been associated with hyperandrogenism and endometrial cancer due to heightened exposure to androgens and estrogens, respectively. [9] During pregnancy, due to activation of SHBG production in the liver by high estrogen levels, SHBG levels increase by five-fold to ten-fold. [9] The high SHBG levels during pregnancy may serve to protect the mother from exposure to fetal androgens that escape metabolism by the placenta. [9] A case report of severe hyperandrogenism in a pregnant woman due to a rare instance of genetic SHBG deficiency illustrates this. [9] [13]

Biochemistry

Biosynthesis

SHBG is produced mostly by the liver and is released into the bloodstream. Other sites that produce SHBG include the brain, uterus, testes, and placenta. [14] Testes-produced SHBG is called androgen-binding protein.

Gene

The gene for SHBG is called Shbg located on chromosome 17 [14] on the short arm between the bands 17p12→p13. [15] Overlapping on the complementary DNA strand is the gene for spermidine/spermine N1-acetyltransferase family member 2 (SAT2). Nearby are the genes for p53 and ATP1B2, and fragile X mental retardation, autosomal homolog 2 (FXR2) on the complementary strand. [16] There are eight exons, of which exon 1 has three variations called 1L, 1T and 1N which are triggered by three promoters: PL, PT and PN respectively. SHBG comes with the 1L, 2, 3, 4, 5, 6, 7, and 8 exons connected together. A variation includes SHBG-T which is missing exon 7 but with exon 1T promoted by promoter PT on the opposite strand, which shared with that for SAT2. [17]

Polymorphisms

There are variations in the genetic material for this protein that have different effects. In humans common polymorphisms include the following:

Rs6259, also called Asp327Asn location 7633209 on Chromosome 17, results in there being an extra N-glycosilation site, and so an extra sugar can be attached. This results in a longer circulation half-life for the protein, and raised levels. A health effect is a lowered risk of endometrial cancer, and another is an increased risk of systemic lupus erythematosus. [18]

Rs6258 also called Ser156Pro is at position 7631360 on the Chromosome 17.

Rs727428 position 7634474 is in several percent of humans. [19]

(TAAAA)(n) is five base pairs that repeats a variable number of times on the opposite DNA strand. [20]

Promoter activation

The mechanism of activating the promoter for SHBG in the liver involves hepatocyte nuclear factor 4 alpha (HNF4A) binding to a DR1 like cis element which then stimulate production. Competing with HNF4A at a third site on the promoter is PPARG-2 which reduces copying the gene to RNA. If HNF4A level is low then COUP-TF binds to the first site and turns off production of SHBG. [7]

Protein

Sex hormone-binding globulin is homodimeric, meaning it has two identical peptide chains making up its structure. The amino acid sequence is the same as for androgen-binding protein but that has different oligosaccharides attached and is produced in testes. [14]

SHBG has two laminin G-like domains which form pockets that bind hydrophobic molecules. The steroids are bound by the LG domain at the amino end of the protein. [7] Inside the pocket of the domain is a serine residue that attracts the two different types of steroids at different points, thus changing their orientation. Androgens bind at the C3 functional groups on the A ring, and estrogens bind via a hydroxyl attached to C17 on the D ring. The two different orientations change a loop over the entrance to the pocket and the position of trp84 (in humans). Thus the whole protein signals what hormone it carries on its own surface. [7] The steroid binding LG domain is coded by exons 2 to 5. [7] A linker region joins the two LG domains together. [7]

When first produced the SHBG precursor has a leading signal peptide attached with 29 amino acids. The remaining peptide has 373 amino acids. [21] There are two sulfur bridges.

The sugars are attached at two different N-glycosylation points on asparagine (351 and 367) and one O-glycosylation (7) point on threonine. [21]

Metals

A calcium ion is needed to link the two elements of the dimer together. Also a zinc ion is used to orient an otherwise disorganised part of the peptide chain. [7]

Regulation

SHBG has both enhancing and inhibiting hormonal influences thus can be viewed as a hepatokine. It decreases with high levels of insulin, growth hormone, insulin-like growth factor 1 (IGF-1), androgens, prolactin and transcortin. High estrogen and thyroxine levels cause it to increase.

In an effort to explain obesity-related reductions in SHBG, recent evidence suggests sugar or monosaccharide-induced hepatic lipogenesis, hepatic lipids in general, and cytokines like TNF-alpha and Interleukin reduce SHBG, whereas insulin does not. As an example anti-psoriatic drugs that inhibit TNF-alpha cause an increase in SHBG. The common downstream mechanism for all of these, including the effect of thyroid hormones [22] was downregulation of HNF4, hepatocyte nuclear factor 4. [23] [24] [25] [26]

Blood values

Reference ranges for blood tests for SHBG have been developed: [27] [28]

PopulationRange
Adult female, premenopausal40–120 nmol/L
Adult female, postmenopausal28–112 nmol/L
Adult male20–60 nmol/L
Infant (1–23 months)60–252 nmol/L
Prepubertal (2 years–8 years)72–220 nmol/L
Pubertal female36–125 nmol/L
Pubertal male16–100 nmol/L

Clinical significance

High or low levels

Levels of sex hormones and SHBG during pregnancy in women. Estrogen, progesterone, testosterone, and SHBG levels during pregnancy in women.png
Levels of sex hormones and SHBG during pregnancy in women.
Levels of SHBG and estradiol during pregnancy in women. For SHBG the lines are the mean and 95th percentile levels while the points are individual measurements. For estradiol the line is the mean level. The dashed parts of the lines are extrapolated. Sex hormone-binding globulin (SHBG) and estradiol levels during pregnancy in women.png
Levels of SHBG and estradiol during pregnancy in women. For SHBG the lines are the mean and 95th percentile levels while the points are individual measurements. For estradiol the line is the mean level. The dashed parts of the lines are extrapolated.
SHBG binding capacity during pregnancy in women. Sex hormone-binding globulin binding capacity during pregnancy in women.png
SHBG binding capacity during pregnancy in women.

SHBG levels are decreased by androgens, administration of anabolic steroids, [32] polycystic ovary syndrome, hypothyroidism, obesity, Cushing's syndrome, and acromegaly. Low SHBG levels increase the probability of Type 2 Diabetes. [33] SHBG levels increase with estrogenic states (oral contraceptives), pregnancy, hyperthyroidism, cirrhosis, anorexia nervosa, and certain drugs. Long-term calorie restriction of more than 50 percent (in rodents) increases SHBG, while lowering free and total testosterone and estradiol. DHEA-S, which lacks affinity for SHBG, is not affected by calorie restriction. [34] Polycystic Ovarian Syndrome is associated with insulin resistance and excess insulin lowers SHBG, which increases free testosterone levels. [35]

In the womb the human fetus has a low level of SHBG allowing increased activity of sex hormones. After birth, the SHBG level rises and remains at a high level throughout childhood. At puberty the SHBG level halves in girls and goes down to a quarter in boys. [7] The change at puberty is triggered by growth hormone, and its pulsatility differs in boys and girls.[ clarification needed ] In pregnant women in the third trimester of pregnancy the SHBG level escalates to five to ten times the usual level for a woman. [7] [9] A hypothesis is that this protects against the effect of hormone produced by the fetus. [7]

Obese girls are more likely to have an early menarche due to lower levels of SHBG. [7] Anorexia or a lean physique in women leads to higher SHBG levels, which in turn can lead to amenorrhea. [7]

Type 2 diabetes

Reduced levels of SHBG and also certain polymorphisms of the SHBG gene are implicated in the development of insulin resistance and type 2 diabetes. [36] Such effects apparently involve direct action at the cellular level where it became apparent that cell membranes of certain tissues contain specific high-affinity SHBG receptors. [37]

Coagulation

SHBG is a useful correlate and indirect marker of estrogen-induced procoagulation and by extension thrombosis, for instance with birth control pills. [38] [39] [40]

Medications

Oral contraceptives containing ethinylestradiol can increase SHBG levels by 2- to 4-fold and decrease free testosterone concentrations by 40 to 80% in women. [41] They can be used to treat symptoms of hyperandrogenism like acne and hirsutism. [41] [9] Some oral contraceptives, namely those containing high doses of ethinylestradiol (which have been discontinued and are no longer marketed), can increase SHBG levels by as much as 5- to 10-fold. [9]

Some medications, such as certain anabolic steroids like mesterolone and danazol and certain progestins like levonorgestrel and norethisterone, have high affinity for SHBG and can bind to it and displace endogenous steroids from it, thereby increasing free concentrations of these endogenous steroids. [42] [43] [44] It has been estimated that therapeutic levels of danazol, methyltestosterone, fluoxymesterone, levonorgestrel, and norethisterone would respectively occupy or displace from testosterone 83–97%, 48–69%, 42–64%, 16–47%, and 4–39% of SHBG binding sites, while others with low affinity for SHBG such as ethinylestradiol, cyproterone acetate, and medroxyprogesterone acetate would occupy or displace from testosterone 1% or fewer SHBG binding sites. [42] [45]

Selective androgen receptor modulators (SARMs) also reduce SHBG. [46]

Affinities of 70 medications for SHBG and CBG [42]
CompoundStructureSHBG
RBA (%)
SHBG
K (106 M−1)
CBG
RBA (%)
CBG
K (106 M−1)
Aminoglutethimide Nonsteroidal<0.01<0.2<0.1<0.1
Androstanolone Steroidal22055001.30.83
Betamethasone Steroidal<0.01<0.2<0.1<0.1
Cholecalciferol Steroidal<0.01<0.2<0.1<0.1
Cimetidine Nonsteroidal<0.01<0.2<0.1<0.1
Clomifene Nonsteroidal<0.01<0.2<0.1<0.1
Cortisol (hydrocortisone) Steroidal0.131.610076
Cortisone acetate Steroidal0.101.2<0.1<0.1
Cyproterone acetate Steroidal0.101.2<0.1<0.1
Danazol Steroidal18240106.5
Dexamethasone Steroidal<0.01<0.2<0.1<0.1
Diazoxide Nonsteroidal<0.01<0.2<0.1<0.1
Diethylstilbestrol Nonsteroidal<0.01<0.2<0.1<0.1
Digitoxin Steroidal<0.01<0.2<0.1<0.1
Digoxin Steroidal<0.01<0.2<0.1<0.1
DL-DOPA Nonsteroidal<0.01<0.2<0.1<0.1
Dopamine Nonsteroidal<0.01<0.2<0.1<0.1
Enclomiphene Nonsteroidal<0.01<0.2<0.1<0.1
Epinephrine Nonsteroidal<0.01<0.2<0.1<0.1
Estradiol Steroidal49680<0.1<0.1
Estradiol benzoate Steroidal0.708.6<0.1<0.1
Ethinylestradiol Steroidal0.809.9<0.1<0.1
Ethisterone Steroidal557800.330.21
Fludrocortisone Steroidal<0.01<0.20.740.47
Fluoxymesterone Steroidal4.860<0.1<0.1
Flutamide Nonsteroidal<0.01<0.2<0.1<0.1
Homovanillic acid Nonsteroidal<0.01<0.2<0.1<0.1
Hydrocortisone hemisuccinate Steroidal<0.01<0.28.75.6
Indometacin Nonsteroidal<0.01<0.2<0.1<0.1
Levonorgestrel Steroidal31420<0.1<0.1
Medroxyprogesterone Steroidal0.151.9138.1
Medroxyprogesterone acetate Steroidal0.081.06.54.2
Melatonin Nonsteroidal<0.01<0.2<0.1<0.1
Mesterolone Steroidal1803600<0.1<0.1
Mestranol Steroidal<0.01<0.2<0.1<0.1
Methoxytryptophol Nonsteroidal<0.01<0.2<0.1<0.1
Methyldopa Nonsteroidal<0.01<0.2<0.1<0.1
Methylserotonin Nonsteroidal<0.01<0.2<0.1<0.1
Methyltestosterone Steroidal39530<0.1<0.1
Metiamide Nonsteroidal<0.01<0.2<0.1<0.1
Metribolone Steroidal1.7210.360.23
Metyrapone Nonsteroidal<0.01<0.2<0.1<0.1
Mexrenone Steroidal<0.01<0.2<0.1<0.1
Nafoxidine Nonsteroidal<0.01<0.2<0.1<0.1
Nandrolone Steroidal5.8720.100.63
Norepinephrine Nonsteroidal<0.01<0.2<0.1<0.1
Norethisterone Steroidal111400.280.18
Noretynodrel Steroidal1.3160.160.10
Normetanephrine Nonsteroidal<0.01<0.2<0.1<0.1
Phenytoin Nonsteroidal<0.01<0.2<0.1<0.1
Potassium canrenoate Steroidal0.182.20.830.53
Prednisolone Steroidal0.040.495941
Prednisone Steroidal0.172.15.03.2
Progesterone Steroidal0.718.83624
Promegestone Steroidal0.0070.090.400.25
Prorenone Steroidal8.2100<0.1<0.1
Reserpine Nonsteroidal<0.01<0.2<0.1<0.1
Rifampin Nonsteroidal<0.01<0.2<0.1<0.1
Serotonin Nonsteroidal<0.01<0.2<0.1<0.1
Spironolactone Steroidal0.030.37<0.1<0.1
Tamoxifen Nonsteroidal<0.01<0.2<0.1<0.1
Testolactone Steroidal<0.01<0.2<0.1<0.1
Testosterone Steroidal10016008.35.3
Testosterone enanthate Steroidal0.0070.086<0.1<0.1
7α-Thioprogesterone Steroidal0.060.743624
7α-Thiospironolactone Steroidal0.597.3<0.1<0.1
Thyroxine Nonsteroidal<0.01<0.2<0.1<0.1
Triiodothyronine Nonsteroidal<0.01<0.2<0.1<0.1
Trimethyltrienolone Steroidal0.90110.110.07
Vanillylmandelic acid Nonsteroidal<0.01<0.2<0.1<0.1
Zuclomifene Nonsteroidal<0.01<0.2<0.1<0.1
The reference ligands (100%) for the RBA Tooltip relative binding affinity (%) values were testosterone for SHBG and cortisol for CBG Tooltip corticosteroid-binding globulin.
Affinities of 21 progestins for SHBG and CBG [44] [47]
ProgestogenSHBG (%)CBG (%)
17α-Allyl-19-nortestosterone <1 ?
Allylestrenol <1 ?
Chlormadinone acetate <1<1
Cyproterone acetate <1<1
Desogestrel <1<1
Dienogest <1<1
Drospirenone <1<1
Etonogestrel 15<1
Gestodene 40<1
Levonorgestrel 50<1
Medroxyprogesterone acetate <1<1
Megestrol acetate <1<1
Nomegestrol acetate <1<1
Norelgestromin <1 ?
Norethisterone 16<1
Noretynodrel <1<1
Norgestimate <1<1
Progesterone <136
Promegestone <1<1
Segesterone acetate <1 ?
Δ4-Tibolone 1<1
Values are RBAs Tooltip relative binding affinities (%). The reference ligand (100%) for SHBG was dihydrotestosterone and for CBG Tooltip corticosteroid-binding globulin was cortisol.
Affinities of 14 AAS for SHBG [43]
CompoundSHBG (%)
5α-Androstane-3β,17β-diol 17
5β-Androstane-3α,17β-diol 5
Dihydrotestosterone 100
Ethylestrenol <1
Fluoxymesterone <1
Mesterolone 440
Metandienone 2
Metenolone 3
Methyltestosterone 5
Metribolone <1
Nandrolone 1
Oxymetholone <1
Stanozolol 1
Testosterone 19
Values are RBAs Tooltip relative binding affinities (%). The reference ligand (100%) for SHBG was dihydrotestosterone.
Affinities of 41 steroids for SHBG [48]
CompoundSHBG (%)
3β-Androstanediol 100
Androstenediol 77
Bolandiol 24
Dihydroethisterone 100
Dihydroethyltestosterone 18–21
Dihydromethylandrostenediol 77
Dihydronandrolone 44
Dihydrotestosterone 100
Dihydrotrestolone 47
4,17α-Dimethyltestosterone 97
Drostanolone 39
Ethisterone 92
Fluoxymesterone 3
11-Ketodihydrotestosterone 0
Medroxyprogesterone acetate 16
Megestrol acetate 0
Mestanolone 84
Methasterone 58
Methyl-1-testosterone 69
Methylandrostenediol 40
Methyltestosterone 64
Mibolerone 6
Nandrolone 16
Nandrolone decanoate 0
Nandrolone phenylpropionate 0
Norethandrolone 3
Norethisterone 21
Normethandrone 7
Oxandrolone 0
Oxymetholone 3
Progesterone 13
Stanozolol 36
1-Testosterone 98
Testosterone 82
Testosterone benzoate 8
Testosterone cypionate 6
Testosterone enanthate 9
Δ4-Tibolone 8
Trestolone 12
Trestolone enanthate 12
Vinyltestosterone 36
Values are RBAs Tooltip relative binding affinities (%). The reference ligand (100%) for SHBG was dihydrotestosterone.
Affinities of 11 steroids for SHBG and CBG [49]
Compound SHBG Tooltip Sex hormone-binding globulin (%) CBG Tooltip Corticosteroid binding globulin (%)
Aldosterone <0.26.0
Corticosterone <0.2107
Cortisol <0.2100
Dexamethasone <0.2<0.1
Dihydrotestosterone 1000.8
Estradiol 8.7<0.1
Metribolone 0.2<0.1
Moxestrol <0.2<0.1
Progesterone <0.225
Promegestone <0.20.9
Testosterone 263
Values are RBAs Tooltip relative binding affinities (%). The reference ligand (100%) for SHBG was dihydrotestosterone and for CBG Tooltip corticosteroid-binding globulin was cortisol.
Affinities of 9 estrogens for SHBG [44] [50]
Compound RBA Tooltip Relative binding affinity to
SHBG Tooltip sex hormone-binding globulin (%)
Bound to
SHBG (%)
Bound to
albumin (%)
17β-Estradiol 503761
Estrone 121680
Estriol 0.3191
Estrone sulfate 0099
17β-Dihydroequilin 30 ? ?
Equilin 82613
17β-Dihydroequilin sulfate 0 ? ?
Equilin sulfate 0 ? ?
Δ8-Estrone  ? ? ?
The reference ligand (100%) for the SHBG RBA Tooltip relative binding affinity (%) values was testosterone.

Endogenous steroids

Measurement

When checking serum estradiol or testosterone, a total level that includes free and bound fractions can be assayed, or the free portion may be measured alone. Sex hormone-binding globulin can be measured separately from the total fraction of testosterone.

A free androgen index expresses the ratio of testosterone to SHBG and can be used to summarize the activity of free testosterone.

Affinity and binding

Affinities of endogenous steroids for SHBG and plasma protein binding [51]
SteroidSHBG affinityPlasma protein binding in menPlasma protein binding in women (follicular phase)
RBA (%)K (106 M−1)Total (nM)Unbound (%)SHBG (%)CBG (%)Albumin (%)Total (nM)Unbound (%)SHBG (%)CBG (%)Albumin (%)
Aldosterone 0.0170.210.3537.10.1021.241.60.2436.80.2321.941.2
3α-Androstanediol 8213000.410.8513.7<0.185.50.0680.7127.9<0.171.4
Androstenediol 9715004.33.2460.4<0.136.32.41.7378.8<0.119.4
Androstenedione 2.3294.17.852.821.3788.05.47.546.631.3784.5
Androsterone 1.1142.04.220.730.5294.51.54.181.770.5493.5
Corticosterone 0.182.2123.390.0977.519.07.03.280.2278.118.4
Cortisol 0.131.64003.910.0889.56.574003.770.1889.76.33
Cortisone 0.222.77216.20.5438.045.35415.81.3038.644.3
Dehydroepiandrosterone 5.366244.133.38<0.192.4173.937.88<0.188.1
11-Deoxycorticosterone 1.9240.202.690.8036.460.10.122.621.9136.958.6
11-Deoxycortisol 1.3161.43.370.6777.118.90.603.241.5777.118.1
Dihydrotestosterone 22055001.70.8859.70.2239.20.650.4778.40.1221.0
Estradiol 496800.0842.3219.6<0.178.00.291.8137.3<0.160.8
Estriol 0.354.30.0378.150.44<0.291.30.108.101.06<0.290.7
Estrone 121500.0813.967.37<0.188.60.233.5816.3<0.180.1
Etiocholanolone 0.111.41.38.150.140.4491.31.28.130.350.4691.1
Pregnenolone 1.1142.42.870.500.1696.52.22.851.210.1695.8
17α-Hydroxypregnenolone 0.192.35.44.270.12<0.195.53.54.260.30<0.195.4
Progesterone 0.718.80.572.390.2617.280.10.652.360.6317.779.3
17α-Hydroxyprogesterone 0.89.95.42.500.3141.355.91.82.440.7342.154.7
Testosterone 1001600232.2344.33.5649.91.31.3666.02.2630.4
In men, the concentrations of SHBG, CBG, and albumin were 28 nM, 0.7 μM, and 0.56 mM, respectively. In women, the concentrations of SHBG, CBG, and albumin were 37 nM, 0.7 μM, and 0.56 mM, respectively.

Synonyms

SHBG has been known under a variety of different names including: [52] [53] [54]

Related Research Articles

<span class="mw-page-title-main">Estrogen</span> Primary female sex hormones

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 activity: estrone (E1), estradiol (E2), and estriol (E3). Estradiol, an estrane, is the most potent and prevalent. Another estrogen called estetrol (E4) is produced only during pregnancy.

<span class="mw-page-title-main">Testosterone</span> Primary male sex hormone

Testosterone is the primary male sex hormone and androgen in males. In humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. It is associated with increased aggression, sex drive, the inclination to impress partners and other courting behaviors. In addition, testosterone in both sexes is involved in health and well-being, where it has a significant effect on overall mood, cognition, social and sexual behavior, metabolism and energy output, the cardiovascular system, and in the prevention of osteoporosis. Insufficient levels of testosterone in men may lead to abnormalities including frailty, accumulation of adipose fat tissue within the body, anxiety and depression, sexual performance issues, and bone loss.

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

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 female secondary sexual characteristics such as the breasts, widening of the hips and a female-associated pattern of fat distribution. It is also important in the development and maintenance of female reproductive tissues such as the mammary glands, uterus and vagina during puberty, adulthood and pregnancy. It also has important effects in many other tissues including bone, fat, skin, liver, and the brain.

<span class="mw-page-title-main">Androgen</span> Any steroid hormone that promotes male characteristics

An androgen is any natural or synthetic steroid hormone that regulates the development and maintenance of male characteristics in vertebrates by binding to androgen receptors. This includes the embryological development of the primary male sex organs, and the development of male secondary sex characteristics at puberty. Androgens are synthesized in the testes, the ovaries, and the adrenal glands.

<span class="mw-page-title-main">Steroid hormone</span> Substance with biological function

A steroid hormone is a steroid that acts as a hormone. Steroid hormones can be grouped into two classes: corticosteroids and sex steroids. Within those two classes are five types according to the receptors to which they bind: glucocorticoids and mineralocorticoids and androgens, estrogens, and progestogens. Vitamin D derivatives are a sixth closely related hormone system with homologous receptors. They have some of the characteristics of true steroids as receptor ligands.

<span class="mw-page-title-main">Transcortin</span> Protein found in humans

Transcortin, also known as corticosteroid-binding globulin (CBG) or serpin A6, is a protein produced in the liver in animals. In humans it is encoded by the SERPINA6 gene. It is an alpha-globulin.

<span class="mw-page-title-main">Dihydrotestosterone</span> Human hormone

Dihydrotestosterone is an endogenous androgen sex steroid and hormone primarily involved in the growth and repair of the prostate, the production of sebum, and body hair composition.

Steroid hormone receptors are found in the nucleus, cytosol, and also on the plasma membrane of target cells. They are generally intracellular receptors and initiate signal transduction for steroid hormones which lead to changes in gene expression over a time period of hours to days. The best studied steroid hormone receptors are members of the nuclear receptor subfamily 3 (NR3) that include receptors for estrogen and 3-ketosteroids. In addition to nuclear receptors, several G protein-coupled receptors and ion channels act as cell surface receptors for certain steroid hormones.

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

Equilin is a naturally occurring estrogen sex hormone found in horses as well as a medication. It is one of the estrogens present in the estrogen mixtures known as conjugated estrogens and esterified estrogens. CEEs is the most commonly used form of estrogen in hormone replacement therapy (HRT) for menopausal symptoms in the United States. Estrone sulfate is the major estrogen in CEEs while equilin sulfate is the second major estrogen in the formulation, present as about 25% of the total.

<span class="mw-page-title-main">2-Methoxyestradiol</span> Chemical compound

2-Methoxyestradiol is a natural metabolite of estradiol and 2-hydroxyestradiol (2-OHE2). It is specifically the 2-methyl ether of 2-hydroxyestradiol. 2-Methoxyestradiol prevents the formation of new blood vessels that tumors need in order to grow (angiogenesis), hence it is an angiogenesis inhibitor. It also acts as a vasodilator and induces apoptosis in some cancer cell lines. 2-Methoxyestradiol is derived from estradiol, although it interacts poorly with the estrogen receptors. However, it retains activity as a high-affinity agonist of the G protein-coupled estrogen receptor (GPER).

<span class="mw-page-title-main">Ethinylestradiol</span> Estrogen medication

Ethinylestradiol (EE) is an estrogen medication which is used widely in birth control pills in combination with progestins. In the past, EE was widely used for various indications such as the treatment of menopausal symptoms, gynecological disorders, and certain hormone-sensitive cancers. It is usually taken by mouth but is also used as a patch and vaginal ring.

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

Norgestimate, sold under the brand names Ortho Tri-Cyclen and Previfem among others, is a progestin medication which is used in birth control pills for women and in menopausal hormone therapy. The medication is available in combination with an estrogen and is not available alone. It is taken by mouth.

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

Danazol, sold as Danocrine and other brand names, is a medication used in the treatment of endometriosis, fibrocystic breast disease, hereditary angioedema and other conditions. It is taken by mouth.

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

Mesterolone, sold under the brand name Proviron among others, is an androgen and anabolic steroid (AAS) medication which is used mainly in the treatment of low testosterone levels. It has also been used to treat male infertility, although this use is controversial. It is taken by mouth.

<span class="mw-page-title-main">Estrogen insensitivity syndrome</span> Medical condition

Estrogen insensitivity syndrome (EIS), or estrogen resistance, is a form of congenital estrogen deficiency or hypoestrogenism which is caused by a defective estrogen receptor (ER) – specifically, the estrogen receptor alpha (ERα) – that results in an inability of estrogen to mediate its biological effects in the body. Congenital estrogen deficiency can alternatively be caused by a defect in aromatase, the enzyme responsible for the biosynthesis of estrogens, a condition which is referred to as aromatase deficiency and is similar in symptomatology to EIS.

<span class="mw-page-title-main">3α-Androstanediol</span> Chemical compound

3α-Androstanediol also known as 5α-androstane-3α,17β-diol and sometimes shortened in the literature to 3α-diol, is an endogenous steroid hormone and neurosteroid and a metabolite of androgens like dihydrotestosterone (DHT).

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

Estetrol (E4), or oestetrol, is one of the four natural estrogenic steroid hormones found in humans, along with estrone (E1), estradiol (E2), and estriol (E3). Estetrol is a major estrogen in the body. In contrast to estrone and estradiol, estetrol is a native estrogen of fetal life. Estetrol is produced exclusively by the fetal liver and is found in detectable levels only during pregnancy, with relatively high levels in the fetus and lower levels in the maternal circulation.

<span class="mw-page-title-main">3β-Androstanediol</span> Chemical compound

3β-Androstanediol, also known as 5α-androstane-3β,17β-diol, and sometimes shortened in the literature to 3β-diol, is an endogenous steroid hormone and a metabolite of androgens like dehydroepiandrosterone (DHEA) and dihydrotestosterone (DHT).

<span class="mw-page-title-main">5α-Dihydroethisterone</span> Chemical compound

5α-Dihydroethisterone is an active metabolite of the formerly clinically used but now-discontinued progestin ethisterone and the experimental and never-marketed hormonal antineoplastic agent ethynylandrostanediol (HE-3235). Its formation from its parent drugs is catalyzed by 5α-reductase in tissues that express the enzyme in high amounts like the liver, skin, hair follicles, and prostate gland. 5α-DHET has significant affinity for steroid hormone receptors and may contribute importantly to the activities of its parent drugs.

The pharmacology of estradiol, an estrogen medication and naturally occurring steroid hormone, concerns its pharmacodynamics, pharmacokinetics, and various routes of administration.

References

  1. 1 2 3 GRCh38: Ensembl release 89: ENSG00000129214 - Ensembl, May 2017
  2. 1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000005202 - Ensembl, May 2017
  3. "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. Bardin CW, Musto N, Gunsalus G, Kotite N, Cheng SL, Larrea F, Becker R (1981). "Extracellular androgen binding proteins". Annual Review of Physiology. 43: 189–98. doi:10.1146/annurev.ph.43.030181.001201. PMID   7011179.
  6. 1 2 Hansson V, Weddington SC, French FS, McLean W, Smith A, Nayfeh SN, Ritzén EM, Hagenäs L (September 1976). "Secretion and role of androgen-binding proteins in the testis and epididymis". Journal of Reproduction and Fertility. Supplement (24 suppl): 17–33. PMID   1069850.
  7. 1 2 3 4 5 6 7 8 9 10 11 12 Hammond GL (September 2011). "Diverse roles for sex hormone-binding globulin in reproduction". Biology of Reproduction. 85 (3): 431–41. doi:10.1095/biolreprod.111.092593. PMC   4480437 . PMID   21613632.
  8. 1 2 Somboonporn W, Davis SR (June 2004). "Testosterone effects on the breast: implications for testosterone therapy for women". Endocrine Reviews. 25 (3): 374–88. doi: 10.1210/er.2003-0016 . PMID   15180949.
  9. 1 2 3 4 5 6 7 8 9 10 Hammond GL (25 April 2017). "Sex Hormone-Binding Globulin and the Metabolic Syndrome". In Winters SJ, Huhtaniemi IT (eds.). Male Hypogonadism: Basic, Clinical and Therapeutic Principles. Humana Press. pp. 305–324. doi:10.1007/978-3-319-53298-1_15. ISBN   978-3-319-53298-1.
  10. Becker K, Bilezikian JP, Bremner WJ, Hung W, Kahn CR (24 April 2001). Principles and Practice of Endocrinology and Metabolism. Lippincott Williams & Wilkins. ISBN   978-0-7817-1750-2 . Retrieved 4 August 2012.
  11. Quirk Jr G, Wendel Jr GD (6 December 2012). "Biologic Effects of Natural and Synthetic Estrogens". In Buchsbaum HJ (ed.). The Menopause. Springer Science & Business Media. pp. 62–. ISBN   978-1-4612-5525-3.
  12. Fritz MA, Speroff L (28 March 2012). Clinical Gynecologic Endocrinology and Infertility. Lippincott Williams & Wilkins. pp. 44–. ISBN   978-1-4511-4847-3.
  13. Hogeveen KN, Cousin P, Pugeat M, Dewailly D, Soudan B, Hammond GL (April 2002). "Human sex hormone-binding globulin variants associated with hyperandrogenism and ovarian dysfunction". J. Clin. Invest. 109 (7): 973–81. doi:10.1172/JCI14060. PMC   150924 . PMID   11927624.
  14. 1 2 3 Hammond GL, Bocchinfuso WP (1996). "Sex hormone-binding globulin: gene organization and structure/function analyses". Hormone Research. 45 (3–5): 197–201. doi:10.1159/000184787. PMID   8964583.
    • Bérubé D, Séralini GE, Gagné R, Hammond GL (1991). "Localization of the human sex hormone-binding globulin gene (SHBG) to the short arm of chromosome 17 (17p12----p13)". Cytogenetics and Cell Genetics. 54 (1–2): 65–7. doi:10.1159/000132958. PMID   2249477.
  15. Joseph DR (January 1998). "The rat androgen-binding protein (ABP/SHBG) gene contains triplet repeats similar to unstable triplets: evidence that the ABP/SHBG and the fragile X-related 2 genes overlap". Steroids. 63 (1): 2–4. doi:10.1016/S0039-128X(97)00087-1. PMID   9437788. S2CID   12825993.
  16. Nakhla AM, Hryb DJ, Rosner W, Romas NA, Xiang Z, Kahn SM (May 2009). "Human sex hormone-binding globulin gene expression- multiple promoters and complex alternative splicing". BMC Molecular Biology. 10 (1): 37. doi: 10.1186/1471-2199-10-37 . PMC   2694190 . PMID   19416531.
  17. Piotrowski P, Gasik R, Lianeri M, Cieślak D, Wudarski M, Hrycaj P, Łacki JK, Jagodziński PP (January 2010). "Asp327Asn polymorphism of sex hormone-binding globulin gene is associated with systemic lupus erythematosus incidence". Molecular Biology Reports. 37 (1): 235–9. doi:10.1007/s11033-009-9639-7. PMID   19649728. S2CID   38541900.
  18. Svartberg J, Schirmer H, Wilsgaard T, Mathiesen EB, Njølstad I, Løchen ML, Jorde R (March 2014). "Single-nucleotide polymorphism, rs1799941 in the Sex Hormone-Binding Globulin (SHBG) gene, related to both serum testosterone and SHBG levels and the risk of myocardial infarction, type 2 diabetes, cancer and mortality in men: the Tromsø Study". Andrology. 2 (2): 212–8. doi: 10.1111/j.2047-2927.2013.00174.x . PMID   24327369. S2CID   206007163.
  19. Thompson DJ, Healey CS, Baynes C, Kalmyrzaev B, Ahmed S, Dowsett M, Folkerd E, Luben RN, Cox D, Ballinger D, Pharoah PD, Ponder BA, Dunning AM, Easton DF (December 2008). "Identification of common variants in the SHBG gene affecting sex hormone-binding globulin levels and breast cancer risk in postmenopausal women". Cancer Epidemiology, Biomarkers & Prevention. 17 (12): 3490–8. doi:10.1158/1055-9965.EPI-08-0734. PMC   2660245 . PMID   19064566.
  20. 1 2 Hammond GL, Underhill DA, Smith CL, Goping IS, Harley MJ, Musto NA, Cheng CY, Bardin CW (May 1987). "The cDNA-deduced primary structure of human sex hormone-binding globulin and location of its steroid-binding domain". FEBS Letters. 215 (1): 100–4. doi:10.1016/0014-5793(87)80121-7. PMID   3569533. S2CID   23058156.
  21. Selva DM, Hammond GL (July 2009). "Thyroid hormones act indirectly to increase sex hormone-binding globulin production by liver via hepatocyte nuclear factor-4alpha". Journal of Molecular Endocrinology. 43 (1): 19–27. doi: 10.1677/JME-09-0025 . PMID   19336534.
  22. Selva DM, Hogeveen KN, Innis SM, Hammond GL (December 2007). "Monosaccharide-induced lipogenesis regulates the human hepatic sex hormone-binding globulin gene". The Journal of Clinical Investigation. 117 (12): 3979–87. doi:10.1172/JCI32249. PMC   2066187 . PMID   17992261.
  23. Simó R, Barbosa-Desongles A, Hernandez C, Selva DM (November 2012). "IL1β down-regulation of sex hormone-binding globulin production by decreasing HNF-4α via MEK-1/2 and JNK MAPK pathways". Molecular Endocrinology. 26 (11): 1917–27. doi:10.1210/me.2012-1152. PMC   5416961 . PMID   22902540.
  24. Simó R, Barbosa-Desongles A, Lecube A, Hernandez C, Selva DM (February 2012). "Potential role of tumor necrosis factor-α in downregulating sex hormone-binding globulin". Diabetes. 61 (2): 372–82. doi:10.2337/db11-0727. PMC   3266423 . PMID   22210320.
  25. Goto A, Morita A, Goto M, Sasaki S, Miyachi M, Aiba N, Terauchi Y, Noda M, Watanabe S (October 2012). "Associations of sex hormone-binding globulin and testosterone with diabetes among men and women (the Saku Diabetes study): a case control study". Cardiovascular Diabetology. 11: 130. doi: 10.1186/1475-2840-11-130 . PMC   3537568 . PMID   23066943.
  26. Unit Code 91215 Archived 2011-07-20 at the Wayback Machine at Mayo Clinic Medical Laboratories. Retrieved April 2011
  27. Becker DM (2019-07-27). "10 Simple Ways To Lower SHBG (#9 Is Fake News!)".
  28. Kerlan V, Nahoul K, Le Martelot MT, Bercovici JP (February 1994). "Longitudinal study of maternal plasma bioavailable testosterone and androstanediol glucuronide levels during pregnancy". Clin. Endocrinol. (Oxf). 40 (2): 263–7. doi:10.1111/j.1365-2265.1994.tb02478.x. PMID   8137527. S2CID   40738152.
  29. 1 2 3 4 O'Leary P, Boyne P, Flett P, Beilby J, James I (1991). "Longitudinal assessment of changes in reproductive hormones during normal pregnancy". Clin Chem. 37 (5): 667–72. doi: 10.1093/clinchem/37.5.667 . PMID   1827758.
  30. Mean F, Pellaton M, Magrini G (October 1977). "Study on the binding of dihydrotestosterone, testosterone and oestradiol with sex hormone binding globulin". Clin. Chim. Acta. 80 (1): 171–80. doi:10.1016/0009-8981(77)90276-5. PMID   561671.
  31. Ruokonen A, Alén M, Bolton N, Vihko R (July 1985). "Response of serum testosterone and its precursor steroids, SHBG and CBG to anabolic steroid and testosterone self-administration in man". Journal of Steroid Biochemistry. 23 (1): 33–8. doi:10.1016/0022-4731(85)90257-2. PMID   3160892.
  32. Ding EL, Song Y, Manson JE, Hunter DJ, Lee CC, Rifai N, Buring JE, Gaziano JM, Liu S (September 2009). "Sex hormone-binding globulin and risk of type 2 diabetes in women and men". The New England Journal of Medicine. 361 (12): 1152–63. doi:10.1056/NEJMoa0804381. PMC   2774225 . PMID   19657112.
  33. Cangemi R, Friedmann AJ, Holloszy JO, Fontana L (April 2010). "Long-term effects of calorie restriction on serum sex-hormone concentrations in men". Aging Cell. 9 (2): 236–42. doi:10.1111/j.1474-9726.2010.00553.x. PMC   3569090 . PMID   20096034.
  34. Manni A, Pardridge WM, Cefalu W, Nisula BC, Bardin CW, Santner SJ, Santen RJ (October 1985). "Bioavailability of albumin-bound testosterone". The Journal of Clinical Endocrinology and Metabolism. 61 (4): 705–10. doi:10.1210/jcem-61-4-705. PMID   4040924.
  35. Le TN, Nestler JE, Strauss JF, Wickham EP (January 2012). "Sex hormone-binding globulin and type 2 diabetes mellitus". Trends in Endocrinology and Metabolism. 23 (1): 32–40. doi:10.1016/j.tem.2011.09.005. PMC   3351377 . PMID   22047952.
  36. Rosner W, Hryb DJ, Kahn SM, Nakhla AM, Romas NA (March 2010). "Interactions of sex hormone-binding globulin with target cells". Molecular and Cellular Endocrinology. 316 (1): 79–85. doi:10.1016/j.mce.2009.08.009. PMID   19698759. S2CID   27912941.
  37. Tchaikovski SN, Rosing J (July 2010). "Mechanisms of estrogen-induced venous thromboembolism". Thromb Res. 126 (1): 5–11. doi:10.1016/j.thromres.2010.01.045. PMID   20163835.
  38. Odlind V, Milsom I, Persson I, Victor A (June 2002). "Can changes in sex hormone binding globulin predict the risk of venous thromboembolism with combined oral contraceptive pills?". Acta Obstet Gynecol Scand. 81 (6): 482–90. PMID   12047300.
  39. Morimont L, Haguet H, Dogné JM, Gaspard U, Douxfils J (2021). "Combined Oral Contraceptives and Venous Thromboembolism: Review and Perspective to Mitigate the Risk". Front Endocrinol (Lausanne). 12: 769187. doi: 10.3389/fendo.2021.769187 . PMC   8697849 . PMID   34956081.
  40. 1 2 IARC Working Group on the Evaluation of Carcinogenic Risks to Humans; World Health Organization; International Agency for Research on Cancer (2007). Combined Estrogen-progestogen Contraceptives and Combined Estrogen-progestogen Menopausal Therapy. World Health Organization. p. 157. ISBN   978-92-832-1291-1.
  41. 1 2 3 Pugeat MM, Dunn JF, Nisula BC (July 1981). "Transport of steroid hormones: interaction of 70 drugs with testosterone-binding globulin and corticosteroid-binding globulin in human plasma". J. Clin. Endocrinol. Metab. 53 (1): 69–75. doi:10.1210/jcem-53-1-69. PMID   7195405.
  42. 1 2 Saartok T, Dahlberg E, Gustafsson JA (1984). "Relative binding affinity of anabolic-androgenic steroids: comparison of the binding to the androgen receptors in skeletal muscle and in prostate, as well as to sex hormone-binding globulin". Endocrinology. 114 (6): 2100–6. doi:10.1210/endo-114-6-2100. PMID   6539197.
  43. 1 2 3 Kuhl H (2005). "Pharmacology of estrogens and progestogens: influence of different routes of administration" (PDF). Climacteric. 8 (Suppl 1): 3–63. doi:10.1080/13697130500148875. PMID   16112947. S2CID   24616324.
  44. Pugeat MM, Dunn JF, Rodbard D, Nisula BC (December 1981). "The significance of drug interactions with human TeBG and CBG under physiological conditions: a new approach". J. Steroid Biochem. 15: 487–90. doi:10.1016/0022-4731(81)90319-8. PMID   7200170.
  45. Machek SB, Cardaci TD, Wilburn DT, Willoughby DS (December 2020). "Considerations, possible contraindications, and potential mechanisms for deleterious effect in recreational and athletic use of selective androgen receptor modulators (SARMs) in lieu of anabolic androgenic steroids: A narrative review". Steroids. 164: 108753. doi:10.1016/j.steroids.2020.108753. PMID   33148520.
  46. Bergink EW, Loonen PB, Kloosterboer HJ (August 1985). "Receptor binding of allylestrenol, a progestagen of the 19-nortestosterone series without androgenic properties". Journal of Steroid Biochemistry. 23 (2): 165–8. doi:10.1016/0022-4731(85)90232-8. PMID   3928974.
  47. Cunningham GR, Tindall DJ, Lobl TJ, Campbell JA, Means AR (September 1981). "Steroid structural requirements for high affinity binding to human sex steroid binding protein (SBP)". Steroids. 38 (3): 243–62. doi:10.1016/0039-128X(81)90061-1. PMID   7197818. S2CID   2702353.
  48. Ojasoo T, Raynaud JP (November 1978). "Unique steroid congeners for receptor studies". Cancer Res. 38 (11 Pt 2): 4186–98. PMID   359134.
  49. Lemke TL, Williams DA (2008). Foye's Principles of Medicinal Chemistry. Lippincott Williams & Wilkins. pp. 1306–. ISBN   978-0-7817-6879-5.
  50. Dunn JF, Nisula BC, Rodbard D (July 1981). "Transport of steroid hormones: binding of 21 endogenous steroids to both testosterone-binding globulin and corticosteroid-binding globulin in human plasma". J. Clin. Endocrinol. Metab. 53 (1): 58–68. doi:10.1210/jcem-53-1-58. PMID   7195404.
  51. "SHBG". GeneCards.
  52. "Sex Steroid-Binding Protein". Steroid-Protein Interactions II. Springer Science & Business Media. 6 December 2012. p. 198. ISBN   978-3-642-82486-9.
  53. Litwack G, Westphal U, eds. (12 December 1994). "Structure, Function, and Regulation of Androgen-Binding Protein?Sex Hormone-Binding Globulin". Vitamins and Hormones: Steroids. Academic Press. p. 200. ISBN   978-0-08-086646-8.

Further reading