Estriol 3-sulfate

On the occurrence and transport of estriol-3-sulfate in human breast cyst fluid: the metabolic disposition of blood estriol-3-sulfate in normal women.[Pubmed:7287868]

J Clin Endocrinol Metab. 1981 Oct;53(4):847-51.

The high concentration of estriol-3-sulfate (E3-3S) in human breast cyst fluid has been confirmed in 14 women with multiple cysts. The concentrations of E3-3S found in individual cysts drained within a short time span from the same patient were variable, the ratios ranging from unity to 40. After the iv administration of [14C]estriol or [3H]E3-3S, only minor accumulation of either isotope was detected in the cyst fluids aspirated 6.5-30 h later. Since surprisingly small amounts of isotopes were found in blood, the metabolism of [3H]E3-3S was studied in 2 normal women. The test compound was injected iv, and blood samples were taken at intervals up to 7.5 h. In addition, total urine was collected for 3 days. The blood clearance of [3H]E3-3S was rapid, with the half-life ranging from 15-30 min. However, E3-3S was only a minor component of the urine, indicating rapid tissue extraction and metabolism rather than renal excretion for the compound. The studies indicate that E3-3S of human breast cyst fluid does not equilibrate rapidly with other body pools and that its uptake, if any, from the blood would be against a gradient.

Bridge-heterologous chemiluminescence enzyme-linked immunosorbent assay of estriol 3-sulfate in pregnancy plasma.[Pubmed:9800282]

Steroids. 1998 Oct;63(10):516-22.

A facile and sensitive chemiluminescence enzyme-linked immunosorbent assay (ELISA) of Estriol 3-sulfate using a bridge-heterologous system was established. 6 alpha-HydroxyEstriol 3-sulfate 6-hemisuccinate was synthesized as a novel hapten. Antisera were raised in male guinea-pigs against 6 alpha-hydroxyEstriol 3-sulfate 6-hemisuccinate-bovine serum albumin (BSA) and 6-oxoEstriol 3-sulfate O-carboxymethyloxime-BSA conjugates. Both haptens were coupled to horseradish peroxidase as an enzyme-label reagent. For separation of free and Estriol 3-sulfate bound to the antibody, the crude globulin fractions of these antisera were immobilized to CNBr-activated Sepharose-4B. The enzyme activity was measured by chemiluminescent reaction using amino-butylethylisoluminol and hydrogen peroxide as a substrate. The immobilized antibody raised against 6 alpha-hydroxyEstriol 3-sulfate 6-hemisuccinate-BSA exhibited a high affinity and an excellent specificity for Estriol 3-sulfate. The two bridge-heterologous ELISAs were more sensitive than the homologous systems. The specificity and sensitivity (10 pg) of the bridge-heterologous chemiluminescence ELISAs was comparable to those of the radioimmunoassays (RIAs). Results obtained by the ELISA and the RIA in pregnancy plasmas, showed excellent correlation between ELISA and RIA (r = 0.96).

Specific antisera for the radioimmunoassay of estriol 3-sulfate.[Pubmed:6523541]

Steroids. 1984 Mar;43(3):235-42.

Antisera were raised in male guinea pigs against 6-oxoEstriol 3-sulfate O-carboxymethyloxime-bovine serum albumin (BSA) conjugate. The antisera to this antigen exhibited high affinity (Ka=4.7 X 10(9)M-1) and excellent specificity for Estriol 3-sulfate, showing slight cross-reactions (less than 0.43%) with other estrogen sulfates, and no cross-reactivities with free estrogens and other steroids (less than 0.01%) except cholesterol sulfate (0.22%). A standard curve using [6, 7-3H]-Estriol 3-sulfate as the radioactive ligand showed high sensitivity in the range of 10-1000 pg Estriol 3-sulfate.

Effect of estriol, estriol-3-sulfate and estriol-17-sulfate on progesterone and estrogen receptors of MCF-7 human breast cancer cells.[Pubmed:3702418]

J Steroid Biochem. 1986 Jan;24(1):357-9.

The levels of progesterone receptors (PR [cytosol (Cy) and nuclear (N)] and estrogen receptors (ER) [cytosol and nuclear; occupied and unoccupied specific binding sites] were evaluated in the MCF-7 cancer cell line incubated with estriol (E3), estriol-3-sulfate (E3-3-S) or estriol-17-sulfate (E3-17-S) for 7 days in culture. Cells were grown in MEM medium containing 2 mM glutamine, 10% v/v dialysed calf serum and penicillin-streptomycin (100 U/ml) in the absence (control) or in the presence of 5 X 10(-8) M E3, E3-3-S or E3-17-S. The total PR (Cy + N) concentration which was 0.47 +/- 0.10 (SE) pmol/mg DNA in the non-treated cells, increased to 1.95 +/- 0.48 in the E3 and to 1.55 +/- 0.26 in the E3-3-S treated cells. No effect (PR: 0.47 +/- 0.15 pmol/mg DNA) was observed with the E3-17-S treatment. Total ER (Cy + N, occupied + unoccupied binding sites) in pmol/mg DNA +/- SE, were as follows: control 0.79 +/- 0.17; + E3: 0.33 +/- 0.09; +E3-3-S: 0.90 +/- 0.18 and +E3-17-S: 1.82 +/- 0.58. The measurement by radioimmunoassay of unconjugated estriol in the culture medium indicated that after incubation with E3-3-S, a fraction (0.5-1%) of the sulfate was hydrolyzed but no hydrolysis was observed in the incubations with E3-17-S. It is concluded that in the MCF-7 human mammary cancer cell line E3 and E3-3-S stimulate PR very significantly, but it is suggested that E3-3-S acts through the hydrolyzed E3. On the other hand, E3-17-S is inactive because it is not hydrolyzed. Consequently, E3-3-S can play an important role in the biological responses of this mammary cancer cell line.