Disease relevance of SHBG

• Estradiol induction of cAMP in breast cancer cells is mediated by foetal calf serum (FCS) and sex hormone-binding globulin (SHBG) [1].

High impact information on SHBG

• Moreover, the LWF diet significantly increased plasma SHBG, suggesting that the divergent effects of substituting LWF for other animal-protein sources on plasma cholesterol and lipoproteins may be partly mediated by variations in plasma sex-hormone status [2].
• They are mosaic proteins possessing a carboxyl-terminal region presenting sequence similarity with plasma sex hormone binding globulin (plasma SHBG), although apparently not involved in steroid binding [3].
• This module is followed by the thrombin-sensitive region (TSR), sensitive to thrombin cleavage, four epidermal growth factor (EGF)-like modules and a last region referred to as the sex hormone binding globulin (SHBG) domain [4].
• Affinity purified antibodies to human sex hormone binding globulin (SHBG) were used in screening a human liver cDNA library, constructed in the expression vector lambda gt11 [5].
• Confirmation that the cDNA clone represented human SHBG was obtained by the finding of a complete agreement in amino acid sequence with several peptide fragments generated from purified SHBG by proteolytic cleavage [5].

Biological context of SHBG

• Serum SHBG concentrations were unchanged during postpartum anoestrus and over the oestrous cycle, as well as in pregnant animals [6].
• The serum SHBG concentrations were about double those found in women with normal menstrual cycles, whereas oestradiol concentrations were much lower [6].
• Structural modifications at C-17 of a steroid molecule involving esterification, epimerization or reduction of the 17 beta-hydroxyl group, or introduction of a bulky 17 alpha group have the effect of decreasing the SHBG binding affinity of the steroid molecule [7].
• These studies show that SHBG is depressed in girls with premature adrenarche; with the increased testosterone levels, this results in a markedly elevated free androgen index, a measure of testosterone which is bioavailable to target tissue [8].
• Serum sex hormone-binding globulin (SHBG) concentrations were of the same magnitude as in control cows during their estrous cycles [9].

Anatomical context of SHBG

• SHBG and "basic" receptors for estradiol and dihydrotestosterone in human uterus cytosol could also be assayed simultaneously [10].
• Pigs lack a sex-hormone binding globulin in blood plasma and, hence, in follicular fluid [11].

Associations of SHBG with chemical compounds

• Bovine steroid hormone and SHBG concentrations postpartum and during the oestrous cycle [6].
• Differentiation between steroid hormone receptors CBG and SHBG in human target organ extracts by a single-step assay [10].
• SHBG binding affinities, relative to the reference hormone 5 alpha-dihydrotestosterone, were estimated for the compounds [7].
• The results demonstrate that binding of steroid hormones to SHBG is facilitated by the 17 beta-hydroxyl group, possibly involving hydrogen binding, and by the methyl group at C-19 of the steroid moiety [7].
• Mean levels of steroids measured were elevated, and SHBG significantly depressed, in the girls with PA, with values (mean +/- SE) for DHEA-S (1.73 +/- 0.17 vs 0.25 +/- 0.06 mumol/l), 5-ADIOL-S (104 +/- 8 vs 31 +/- 4 nmol/l), AD (0.89 +/- 0.06 vs 0.62 +/- 0.04 nmol/l), and T (0.49 +/- 0.03 vs 0.23 +/- 0.06 nmol/l) [8].

Analytical, diagnostic and therapeutic context of SHBG

• Serum sex hormone binding globulin (SHBG), testosterone (T), DHEA sulphate (DHEA-S), androstenedione (AD) and delta 5-androstene-3 beta,17 beta-diol sulphate (5-ADIOL-S) levels were measured by specific radioimmunoassay in 16 girls presenting with premature adrenarche (PA) and in 14 normal girls [8].
• MCF-7 cells were maintained in DCC-FCS (treated with DCC to remove steroids), in SHBG-FREE/DCC-FCS (treated with DCC and with a specific affinity chromatography to remove bovine sex hormone-binding globulin), or in serum-free medium (SFM) [1].

References