Serum estradiol

NAGATA c, KABUTO M, KURISU Y, SHIMIZU H (1997) Decreased serum estradiol concentration associated with high dietary intake of soy products in premenopausal women. Nutr Cancer. 29 228-33. 

The effects of raloxifene in premenopausal women have been analyzed in subjects with normal ovarian function treated with high doses (100 to 400 mg daily) at either different time points of their menstrual cycle or continuously for 4 weeks (Baker et al. 1998). Raloxifene did not prevent ovulation, nor did it alter the length of the menstrual cycle or the day of the LH surge. However, it did stimulate FSH secretion, increase serum estradiol levels, and decrease serum PRL. These results are also similar to those reported for premenopausal women taking tamoxifen (Jordan et al. 1991) and are indicative of some antiestrogenic action at either the hypothalamic and/or pituitary level. 

Reindollar R, Koltun W, Parsons A, Rosen A, Siddhanti S, Plouffe Jr L (2002) Effects of oral raloxifene on serum estradiol levels and other markers of estrogenicity. Fertil Steril 78 469-472... 

Uebelhart B, Herrmann F, Pavo I, Draper MW, Rizzoli R (2004) Raloxifene treatment is associated with increased serum estradiol and decreased bone remodeling in healthy middle-aged men with low sexhormone levels. J Bone Miner Res 19 1518-1524... 

In those with serum estradiol concentrations of 5-10 pmol/L, invasive breast cancer incidence was reduced by 67% (HR = 0.33, 95% Cl = 0.13-0.84 ARR = 40 cases per 10,000 woman-years) in the raloxifene group compared to those receiving placebo. In women with serum estradiol levels < 5 pmol/L, the 48% reduction in invasive breast cancer incidence for the raloxifene group compared to placebo was not significant (HR = 0.52, 95% Cl = 0.26-1.06 ARR =11 cases per 10,000 woman-years). However, the interaction test showed that the magnitude of reduction in breast cancer incidence with raloxifene was independent of estradiol level (interaction p = 0.317). 

Fig. 10.12. Effect of raloxifene on the risk of invasive breast cancer at different serum estradiol levels evaluated in two different studies. Elaborated from Lippman et al. (2001) and Cummings et al. (2002a)...

Cummings SR, Duong T, Kenyon E et al. (2002a) Serum estradiol level and risk of breast cancer during treatment with raloxifene. J Am Med Assoc 287 216-220... 

Cummings SR (2002b) Measurement of serum estradiol levels in postmenopausal women. J Am Med Assoc 288 451... 

Martino S, Powles T, Cauley JA et al. (2004b) Effect of raloxifene on incidence of invasive breast cancer in postmenopausal women stratified by baseline serum estradiol results of the Continuing Outcomes Relevant to Evista (CORE) trial. San Antonio Breast Cancer Symposium... 

A possible explanation for these results may be twofold. First, the raloxifene doses were too low to reduce or reverse the proliferative effect of serum estradiol in normal ovulatory women. In fact, in postmenopausal women serum estradiol levels are about tenfold lower in comparison with normally cycled premenopausal women. Second, it is possible that in postmenopausal women ERs have a different intratumoral pattern in terms of concentration, expression, and affinity in comparison with premenopausal women. 

Recently, a Japanese research group published preclinical safety and efficacy data of an oral antiestrogen (TZE-5323) (Saito et al. 2003). This drug has been shown to have a strong affinity for human ERa and ER/i and a dose-dependent capacity to inhibit estradiol-stimulated transcriptional activation (Saito et al. 2003). In the experimental endometriosis model in rats, TZE-5323 dose-dependently reduced the volume of the endometrial implant with an effectiveness similar to that of danazol and leuprorelin acetate without causing significant changes in bone mineral density and in serum estradiol levels (Saito et al. 2003). 

Cauley J, Lucas FL, Kuller LH et al. (1999) Elevated serum estradiol and testosterone concentrations are associated with a high risk of breast cancer. Ann Intern Med 130(4 Pt l) 270-277... 

Nozaki O, Ohba Y, Imai K. 1988. Determination of serum estradiol by normal-phase high-performance liquid chromatography with peroxyojalate chemiluminescence detection. Anal Chim Acta 205 255-260. 

Rats fed diets containing 30 or 300ppm ammonium perfluorooctanoate for 2 years had increased liver weights with occasional necrosis and an apparent dose-dependent increase in Leydig cell adenomas, but there was no evidence of an increased incidence of hepatocellular carcinoma. In a follow-up study in male mice, 300ppm in the diet for 2 years caused increases in liver, Leydig cell, and pancreatic acinar cell tumors that may have been associated with the peroxisome-proliferating capabilities of the compound. Ammonium perfluorooctanoate also produced sustained increases in serum estradiol concentrations. ... 

E. Therapeutic response In anovulatory women, the goal of therapy is adequate follicular development as determined by ultrasound in combination with measurement of serum estradiol levels. In men, the aim of treatment is maintenance of serum testosterone levels within the normal range. 

Attempts to identify hyper-responders continue. There is a significant predictive association between serum estradiol (E2) concentrations measured on stimulation days 3 and 5 and both ovarian hyper-responses and extreme responses in in vitro fertilization. However, the practical clinical value of stimulated serum estradiol (E2) concentrations for the prediction of hyper-responses is low, because of modest sensitivity and a high false-positive rate. For prediction of extreme responses the clinical value of stimulated E2 concentrations is moderate (30). 

Hendriks DJ, Klinkert ER, Bancsi LFJMM, Looman CWN, Habbema JDF, Te Velde ER, Broekmans FJ. Use of stimulated serum estradiol measurements for the prediction of hyperresponse to ovarian stimulation in in vitro fertilization (IVF). J Assist Reprod Genet 2004 21 65-72. 

Dutch workers concluded that patients who were still having a menstrual cycle had a high chance (81%) of developing ovarian cysts during tamoxifen treatment, but that postmenopausal women taking tamoxifen only developed ovarian cysts if their ovaries were able to respond to FSH stimulation, as shown by serum estradiol production (69). Differences in patient populations might explain why some workers (70) still find no association in their patients between tamoxifen and ovarian pathology. 

The relation between antipsychotic drug-induced hyperprolactinemia and hypoestrogenism has been studied in 75 women with schizophrenia (762). Serum estradiol concentrations were generally reduced during the entire menstrual cycle compared with reference values. There was hypoestrogenism, defined as serum estradiol concentrations below 30 pg/ml in the follicular phase and below 100 pg/ml in the periovulatory phase, in about 60%. 

Serum TSH concentrations are moderately but significantly reduced by troleandomycin compared with josamy-cin or placebo given over 10 days. At the same time serum estradiol concentration was significantly increased (1152). 

Gonadorelin is administered intravenously, 5 pg every 90 minutes from a portable pump. The woman is followed carefully with serum estradiol levels, and an ovarian ultrasound examination is done weekly before refilling the GnRH pump. When an ovarian follicle reaches 14 mm in diameter, ovulation is induced with hCG, 5000 units subcutaneously, and the luteal phase is maintained with hCG, 1500 units every 3 days for 12 days. 

In hypothalamic hypogonadism and for in vitro fertilization, one or two ampules are administered daily for 5-12 days until evidence of adequate follicular maturation is present. Serum estradiol levels should be measured and a cervical examination performed every 1 or 2 days. When appropriate follicular maturation has occurred, hMG or FSH is discontinued the following day, hCG (5000-10,000 IU) is administered intramuscularly to induce ovulation. 

Shiverick KT, Muther TF. 1983. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) effects on hepatic microsomal steroid metabolism and serum estradiol of pregnant rats. Biochem Pharmacol 32 991-995. 

Few studies have investigated the reproductive toxicity of DEHP in female animals. When female mice were exposed to a dietary dose of 420 mg/kg/day DEHP for 105 days and mated with unexposed males, combined weights of the ovaries, oviducts, and uterus were reduced, and no litters were produced. When female mice exposed to 14 or 140 mg DEHP/kg/day were mated with males given these same doses, there was a dose-related decline in the number of litters, live pups per litter, and live pup weight. Short-term gavage exposure to a very high level of DEHP (2,000 mg/kg/day), particularly with respect to possible human exposure, had clear effects on estradiol synthesis, manifested as decreased serum estradiol levels and anovulatory cycles and polycystic ovaries, in female rats. These data indicate that oral exposure to DEHP can affect reproductive processes in female rodents. 

Rat (Sprague- Dawley) 1-10 d 1x/d (GO) 2000 F (suppressed ovulation with 25% decrease in preovulatory follicle 1 granulosa cells and decresed serum estradiol) Davis et al. 1994a... 

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