Estrone 3-sulfate

Sulfatase Cleavage of O-sulfates and sulfamates Cydamate, amygdalin, estrone sulfate... 

Current information indicates that OATP-E [30] is ubiquitously expressed in tissues [30, 37]. Some substrates transported by OATP-E include estrone-sulfate [30], prostaglandin E2 [30] and taurocholate [37]. The capacity for T3 and T4 transport and the wide tissue distribution suggests that OATP-E is largely responsible for the peripheral uptake of thyroid hormone [37]. Further studies are required to assess whether OATP-E is an important determinant of drag distribution. 

Conjugated equine estrogens are composed of estrone sulfate (50% to 60%) and other estrogens such as equilin and 17 a-dihydroequilin. 

Pasqualini JR, Chetrite G, Nguyen BL, Maoloche C, Delalonde M, Talbi M, Feinstein MC, Blacker C, Botella J and Paris J (1995) Estrone sulfate-sulfatase and 17/3-hidroxis teroid dehydrogenase activities a hypothesis for their role in the evolution of human breast cancer from hormone-dependence to hormone-independence. J Steroid Biochem Mol Biol 53 407... 

Phenoxymethyl penicillin potassium, 7,249 Phenylephrine hydrochloride, 3,483 Piperazine estrone sulfate, 5, 375 Primidone, 2,409... 

There have been several studies that underscore the importance of unbound concentration in cell-based studies of receptor function. In a model study of the effect of plasma protein binding on the renal transport of organic anions using the expression of various organic anion transporters (OATPs) in Xenopus oocytes, the transport of ochratoxin A, methotrexate, and estrone sulfate was found to be strongly inhibited by the addition of human serum albumin to the culture medium [16]. Similarly, the addition of oq-acid glycoprotein was found to reverse the blockade of sodium-ion current by cocaine in a preparation of cardiac myocytes [17]. 

In STP effluents, total extractable estrogens and conjugates have been detected at levels up to 1 /jg/L [9,11,26]. Despite the wide variability in terms of removal efficiency reported for different WWTPs, a general trend has been observed with respect to the identity of the compounds most frequently detected in WWTP effluents. Thus, of the various compounds most commonly monitored - namely, estradiol, its metabolites estriol and estrone, and the synthetic estrogen ethynylestradiol - estrone is the most ubiquitous both in WWTP effluents and in environmental waters in general, while the most potent estrogens estradiol and ethynylestradiol have only occasionally been detected [26,40-42]. As for the conjugates, the very few studies that have attempted their determination pointed out estrone sulfates as the most abundant, while glu-curonides are most often found below the limit of detection [26,36,38,39]. 

The biologically inactive estrone sulfate (EIS) and dehydro-epiandrosterone-sulfate (DHEAS) are the most abundant circulating estrogenic precursors in the plasma of post-menopausal women [103]. Desulfation of inactive steroid-3-0-sulfates by estrone-sulfatase (STS) plays a key role in the regulation of levels of receptor-active estrogenic steroids (estradiol and androstenediol) in breast cancer cells (Fig. 9). There is strong evidence suggesting that estrone sulfatase (STS) and DHEA-sulfatase are the same enzyme [103]. 

Pharmacokinetics Readily absorbed from the gastrointestinal (Gl) tract. Widely distributed. Protein binding 50%-80%. Rapidly metabolized in liver and Gl tract to estrone sulfate and conjugated and unconjugated metabolites. Excreted in urine and bile. Half-life Unknown. 

Esters Aspirin, procaine, alkaloids, estrone sulfate, dexmethasone sodium phosphate... 

However, in 12 patients who took letrozole 2.5 mg/day for 6 weeks with and without tamoxifen 20 mg/day plasma concentrations of letrozole were reduced by 38% during combination therapy (39). Tamoxifen did not significantly alter the effect of letrozole in suppressing estradiol, estrone, and estrone sulfate. The authors suggested that sequential therapy might be preferable with these two drugs. 

Piperazine estrone sulfate. Study duration 14 weeks. Decrease of wakefulness and awakenings. Increase of REM sleep. Estrogen effect on hot flashes, mood or anxiety similar to placebo. 

Taylor and coworkers have prepared o-fluoromethyl and o-difluoromethyl estrone sulfates82 and shown that these compounds are good substrates for steroid sulfatases.83 The phenol product of hydrolysis of o-fluoromethyl estrone sulfate undergoes heterolytic cleavage to form a quinone methide that inactivates the steroid sulfatase (Scheme 20C).83 The phenol product of hydrolysis of o-difluoromethyl estrone sulfate breaks down first to a quinone methide and then to the o-formyl estrone, which also inactivates the steroid sulfatase.83... 

The activity of estrogens in a conjugated form is generally less than that of the free form, however, Grant and Glen216 have reported that sodium equilin sulfate and sodium equilenin sulfate, in contrast to sodium estrone sulfate, are more active orally in adult, ovariectomized mice than are the unconjugated forms. The administration of estrone sulfate labeled with S36 is followed immediately by hydrolysis.217... 

Common Name Estropipate Piperazine estrone sulfate Pipestrone Chemical Abstracts Registry No. 7280-37-7... 

Bulk/tablets Ethambutol HPLC ISTD-ethyl paraben, powder, glass beads, mobile phase Cg, Zorbax P04 (6.8 g/730 m y-CH3CN (730 270), 1 ml/min 210 nm Method review, resolve equilin sulfate, estrone sulfate along with other conjugates history [478] fluorodensi-tometry [480] USP 23 [5] HPLC [880-882] [479]... 

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