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Changes in serum apo-lipoprotein AI and sex-hormone-binding globulin levels after treatment with two different progestins administered alone and in combination with ethinyl estradiol.

Twenty women, oophorectomized as part of the surgical treatment for cervical carcinoma in either clinical stage IB or IIA but otherwise healthy, participated in the study. After a period of six weeks without hormonal treatment, ten of them were given 150 micrograms desogestrel (DG) daily for three weeks followed by 150 micrograms DG + 30 micrograms ethinyl estradiol (EE) for six weeks and, finally, 30 micrograms EE alone for three weeks. The remaining ten women were given 150 micrograms levonorgestrel (NORG) and EE in a similar regimen. Before treatment and after each period of treatment, apo-lipoprotein AI and sex-hormone-binding globulin (SHBG) were assayed in serum. Both progestins decreased apo-AI and SHBG when given alone, thereby indicating an "androgenic" influence. In combination with EE, however, DG seems to be less "anti-oestrogenic" than NORG, as judged from the higher apo-AI and SHBG values after the combination DG + EE compared to those after NORG + EE.

Adult↗

Treatment of acne with cyproterone acetate and ethinyl estradiol.

Tablets containing 2 mg cyproterone acetate and 0.05 mg ethinyl estradiol in a calendar package of 21 days were used as an oral contraceptive to treat acne. The series comprised 20 patients. The women were 18--43 years of age, and all had acne which had previously been resistant to therapy. The treatment was continued for 6 months. Serum testosterone, 17-OHCS, 17-KS, serum ALAT and gamma-GT were recorded prior to the treatment at 3 and 6 months. Ten patients responded well to the treatment, 5 responded moderately well, 3 experienced no change, and 2 became worse. The serum testosterone level fell during the therapy and the ALAT level rose, though only one pathological ALAT value was recorded.

17-Hydroxycorticosteroids↗

Estrogens in the nervous system: mechanisms and nonreproductive functions.

The past decade has witnessed a growing interest in estrogens and their activity in the central nervous system, which was originally believed to be restricted to the control of reproduction. It is now well accepted that estrogens modulate the activity of all types of neural cells through a multiplicity of mechanisms. Estrogens, by binding to two cognate receptors ERalpha and ERbeta, may interact with selected promoters to initiate the synthesis of target proteins. Alternatively, the hormone receptor complex may interfere with intracellular signaling at both cytoplasmic and nuclear levels. The generation of cellular and animal models, combined with clinical and epidemiological studies, has allowed us to appreciate the neurotrophic and neuroprotective effects of estrogens. These findings are of major interest because estradiol might become an important therapeutic agent to maintain neural functions during aging and in selected neural diseases.

Animals↗

A placebo-controlled trial of ethinyl oestradiol and norethisterone in climacteric women.

A placebo-controlled trial has shown that 15 microgram of ethinyl oestradiol is as effective as 25 microgram daily in reducing both menopausal symptoms and the urinary excretion of calcium and hydroxyproline. Norethisterone 5 mg daily also showed a significant reduction in the climacteric symptoms but was less effective than either of the ethinyl oestradiol doses.

Calcium↗

Effect of estrogen and progesterone on L-dopa induced dyskinesia in MPTP-treated monkeys.

A group of 4 cynomolgus monkeys was rendered parkinsonian by the toxin MPTP and then treated daily with L-DOPA until all animals developed dyskinesia. At this point, 17 beta-estradiol, 17 alpha-estradiol and progesterone were injected s.c. singly or in combination for 7 days and the treatment with L-DOPA reinstituted. Our results show that the pretreatment with 17 beta-estradiol reduced the dyskinetic effect without altering the therapeutic response to L-DOPA, while 17 alpha-estradiol did not alter the dyskinetic and the antiparkinsonian effect.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗

Evaluation of new estrogen-linked 2-chloroethylnitrosoureas. I. Short term anticancer efficacy in methylnitrosourea-induced rat mammary carcinoma and hormonal activity in mice.

Short-term treatment of N-methyl-N-nitrosourea-induced mammary carcinomas in Sprague-Dawley rats with estradiol-linked nitrosoureas shows that the compounds in which the cytotoxic group is linked to position 17 of estradiol are superior to the 3-ester analogue. Moreover, N-(2-chloroethyl)-N-nitroso-carbamoyl (CNC)-L-alanyl-L-alanine-estradiol-3-ester is more effective and less toxic than CNC-L-alanine-estradiol-3-ester, being equivalent to ovariectomy in its therapeutic efficacy. Unlinked CNC-amino acid or-dipeptide in admixture with estradiol is less effective. Linked compounds at therapeutic dosages display estrogenic activity.

Animals↗

In vitro steroid metabolic studies in human testes I: Effects of estrogen on progesterone metabolism.

A technique of incubation of testicular tissue in vitro with radiolabeled precursors was applied in the investigation of the steroid biosynthesis by testes of four young men after long-term, high-dose estrogen treatment. A positive correlation between plasma and testicular steroid levels, and in vitro capacity of the testes to metabolize progesterone was demonstrated. Estrogen administration produced a very significant inhibition of plasma and testicular levels of testosterone. The in vitro synthesis of testosterone from progesterone was very severely impaired; especially 17alpha-hydroxylation of progesterone. 20alpha-hydroxysteroid-dehydrogenase activity was found to be increased after estrogen treatment, both in vivo and in vitro. These findings suggest that testicular 17alpha-hydroxylase activity (and possibly also 17-20 lyase activity) is either under gonadotropin regulation, or is directly suppressed by estrogen. This could result by decreased enzyme synthesis, direct enzyme inhibition or affectation of the cofactors or cytochromes necessary for the enzymatic activity. 20alpha-reduction of C21-steroids would represent an alternative pathway for their catabolism, not regulated by gonadotropin or not affected by estrogen, that would be significant in situations with reduced 17alpha-hydroxylase activity.

Adult↗

Estrogens: trophic and protective factors in the adult brain.

Our appreciation that estrogens are important neurotrophic and neuroprotective factors has grown rapidly. Although a thorough understanding of the molecular and cellular mechanisms that underlie this effect requires further investigation, significant progress has been made due to the availability of animal models in which we can test potential candidates. It appears that estradiol can act via mechanisms that require classical intracellular receptors (estrogen receptor alpha or beta) that affect transcription, via mechanisms that include cross-talk between estrogen receptors and second messenger pathways, and/or via mechanisms that may involve membrane receptors or channels. This area of research demands attention since estradiol may be an important therapeutic agent in the maintenance of normal neural function during aging and after injury.

Animals↗

Distinct modulation of alkaline phosphatase isoenzymes by 17beta-estradiol and xanthohumol in breast cancer MCF-7 cells.

OBJECTIVES: To examine the effect of 17beta-estradiol and xanthohumol in alkaline phosphatase (ALP) expression and activity in breast cancer MCF-7 cells. DESIGN AND METHODS: ALP isoenzymes expression was evaluated by RT-PCR and Western blotting. ALP activity was measured by spectrophotometry. Cell proliferation and apoptosis were examined by MTT and immunostaining for KI67 and TUNEL, respectively. RESULTS: ALP isoenzymes expression and activity were decreased by 1 nM 17beta-estradiol. Pure estrogenic antagonist (ICI 182,780) reversed 17beta-estradiol-inhibiting effect in TNS-ALP expression. RNA and protein expression of IALP, but not TNS-ALP, was also decreased by incubation with 10 microM xanthohumol (IC(50)) and was accompanied by a significant reduction in ALP activity. Treatment with 17beta-estradiol enhanced cell proliferation and decreased apoptosis. Conversely, xanthohumol incubation inhibited cell viability and apoptosis. CONCLUSION: Estrogens and xanthohumol differently modulate ALP isoenzymes. ALP loss associated with increased cell proliferation. Modulation of this enzyme by 17beta-estradiol and xanthohumol might provide therapeutic strategies against hormone-dependent breast cancer.

Alkaline Phosphatase↗

Estrogen therapy for experimental intracerebral hemorrhage in rats.

OBJECT: The aims of this study were to determine the following: whether there are sex differences in intracerebral hemorrhage (ICH) induced brain injury in rats, whether delayed administration of 17beta-estradiol can reduce ICH-induced brain damage, and whether these effects are estrogen receptor (ER)-dependent. METHODS: Male and female Sprague-Dawley rats received an infusion of 100 microl autologous whole blood into the right basal ganglia. Twenty-four hours later the rats were killed. The effects of 17beta-estradiol on ICH-induced brain injury were examined by measuring brain edema and neurological deficits. Both ER-alpha and hemeoxygenase (HO)-1 were investigated through Western blot and immunohistochemical analysis. Brain edema was significantly less severe in female compared with that in male rats. The ER antagonist ICI 182,780 exacerbated ICH-induced brain edema in female but not in male rats, indicating that ER-alpha activation during ICH is protective in female rats. Administration of exogenous 17beta-estradiol in male, but not in female, rats significantly attenuated brain edema, neurological deficits, and ICH-induced changes in HO-1 when given 2 hours after hemorrhage. The effects of exogenous 17beta-estradiol occurred through an ER-independent mechanism. CONCLUSIONS: Results in this study indicate that 17beta-estradiol could be a potential therapeutic agent for ICH.

Animals↗

Estradiol protects mesencephalic dopaminergic neurons from oxidative stress-induced neuronal death.

Oxidative stress is important in the process of dopaminergic neuronal degeneration in Parkinson's disease. Recent studies suggest that estrogens have neuroprotective effects in neurodegenerative disorders, including Alzheimer's disease. In the present study, we investigated neuroprotection against oxidative stress afforded by estradiol using primary neuronal culture of the rat ventral mesencephalon. Oxidative stress induced by glutamate, superoxide anions, and hydrogen peroxide caused significant neuronal death. Although simultaneous administration of 17beta-estradiol and glutamate did not show any significant effects, preincubation with 17beta-estradiol provided significant neuroprotection against glutamate-induced neurotoxicity (ED50 was 50 microM for dopaminergic and 15 microM for nondopaminergic neurons). Neuroprotection occurred even after a brief preincubation with 17beta-estradiol and was not significantly blocked by either an estrogen receptor antagonist or a protein synthesis inhibitor. These findings indicate that the neuroprotection against glutamate neurotoxicity is mediated by neither estrogen receptors nor activation of genome transcription. Other steroids (corticosterone, testosterone, and cholesterol) did not provide significant neuroprotection against glutamate-induced neurotoxicity. Furthermore, preincubation with 17beta-estradiol provided neuroprotection against neuronal death induced by both superoxide anions and hydrogen peroxide. Dichlorofluorescin diacetate, a marker of oxygen radicals, revealed that preincubation with 17beta-estradiol suppressed intracellular oxygen radicals induced by hydrogen peroxide. The biologically inactive stereoisomer of estradiol, 17alpha-estradiol, provided neuroprotection against glutamate-induced toxicity in dopaminergic neurons, as well as the 17beta isoform. 17Alpha-estradiol may be a potential therapeutic agent used to prevent dopaminergic neuronal death induced by oxidative stress in Parkinson's disease.

Animals↗

Effect of Medrogestone on 17beta-hydroxysteroid dehydrogenase activity in the hormone-dependent MCF-7 and T-47D human breast cancer cell lines.

Estradiol (E2) is one of the most important hormones supporting the growth and evolution of breast cancer. Consequently, to block this hormone before it enters the cancer cell, or in the cell itself, has been one of the main targets in recent years. In the present study we explored the effect of Medrogestone (Prothil) on 17beta-hydroxysteroid dehydrogenase (17beta-HSD) activities of the hormone-dependent MCF-7 and T-47D human breast cancer cell lines. Using physiological doses of estrone ([3H]-E1: 5 x 10(-9) mol/l) this estrogen is converted in a great proportion to E2 in both cell lines. After 24 h of the cell culture, Medrogestone significantly inhibits this transformation in a dose-dependent manner by 39% and 80% at 5 x 10(-8) M and 5 x 10(-5) M, respectively in T-47D cells; the effect is less intense in MCF-7 cells: 25% and 55% respectively. The IC50 values are 0.45 micromol/l in T-47D and 17.36 micromol/l in MCF-7 cells. It is concluded that the inhibition provoked by Medrogestone on the reductive 17beta-HSD activity involved in the local biosynthesis of the biologically active estrogen estradiol, may constitute a new therapeutic approach for the treatment of breast cancer.

17-Hydroxysteroid Dehydrogenases↗

Transdermal estradiol/norethisterone. A review of its pharmacological properties and clinical use in postmenopausal women.

The combined transdermal estradiol/norethisterone therapeutic system is designed to deliver both estradiol and norethisterone into the systemic circulation at a constant rate for up to 4 days when affixed to the skin. Transdermal administration avoids hepatic first-pass metabolism, allowing therapeutic concentrations of the progestogen and estrogen to be maintained in postmenopausal women following low dose administration. Transdermal norethisterone does not appear to alter the potentially beneficial effects of transdermal estradiol on total cholesterol, low-density lipoprotein (LDL) or triglyceride levels, or metabolic parameters of bone resorption or vaginal cytology. Protection of the endometrium from the effects of unopposed estradiol is achieved by sequential treatment with transdermal estradiol/norethisterone for 2 weeks of each 28-day cycle, and the majority of patients experience a regular vaginal bleeding pattern with this treatment regimen. Menopausal symptoms are improved to a similar extent during the transdermal estradiol-only and combined estradiol/norethisterone treatment phases. The transdermal therapeutic system has been well accepted by patients in clinical trials. It is generally well tolerated, the most common adverse effect being local irritation at the site of application. Estrogen- and progestogen-related systemic adverse events are reported in a small proportion of patients. Thus, the combined estradiol/norethisterone transdermal delivery system offers a more convenient and consistent method of progestogen administration. Together with its therapeutic efficacy when administered at lower dosages than oral therapy, it is likely to further improve patient compliance during hormone replacement therapy.

Administration, Cutaneous↗

Effectiveness of norgestimate and ethinyl estradiol in treating moderate acne vulgaris.

BACKGROUND: An excess of androgen is believed to contribute to development of acne in some patients. Because oral contraceptives (OCs) may reduce the active androgen level, hormonal therapy with OCs has been used successfully to treat patients with acne, although this treatment has previously not been studied in placebo-controlled trials. OBJECTIVE: Our purpose was to evaluate the efficacy of a triphasic, combination OC (ORTHO TRI-CYCLEN [Ortho-McNeil Pharmaceutical, Raritan, N.J.], norgestimate/ethinyl estradiol) compared with placebo in the treatment of moderate acne vulgaris. METHODS: Two hundred fifty-seven healthy female subjects, 15 to 49 years of age with moderate acne vulgaris, were enrolled in a multicenter, randomized, double-blind, placebo-controlled clinical trial. Each month for 6 months, subjects received either 3 consecutive weeks of the OC (i.e., tablets containing a fixed dose of ethinyl estradiol [0.035 mg] and increasing doses of norgestimate [0.180 mg, 0.215 mg, 0.250 mg]) followed by 7 days of inactive drug or placebo (color-matched tablets). Efficacy was assessed by facial acne lesion counts, an investigator's global assessment, a subject's self-assessment, and an analysis of within-cycle variation (cycle 6) in lesion counts. RESULTS: Of the 160 subjects in whom efficacy could be evaluated, the OC group showed a statistically significantly greater improvement than the placebo group for all primary efficacy measures. The mean decrease in inflammatory lesion count from baseline to cycle 6 was 11.8 (62.0%) versus 7.6 (38.6%) (p = 0.0001), and the mean decrease in total lesion count was 29.1 (53.1%) versus 14.1 (26.8%) (p = 0.0001) in the OC and placebo groups, respectively. In the investigator's global assessment, 93.7% of the active treatment group versus 65.4% of the placebo group were rated as improved at the end of the study (p < 0.001). Six of the seven secondary efficacy measures (total comedones, open comedones, closed comedones, papules, pustules, and the subject's self-assessment of study treatment) were also significantly more favorable in the OC group compared with the placebo group. CONCLUSION: An OC containing 0.035 mg of ethinyl estradiol combined with the triphasic regimen of norgestimate is a safe and effective treatment of moderate acne vulgaris in women with no known contraindication to OC therapy.

Acne Vulgaris↗