Danazol Inhibits Steroidogenesis**Supported by United States Public Health Service Grant HD 07923-04 and Rockefeller Foundation Grant RF 65040

Structural Insights into Endobiotic Reactivation by Human Gut Microbiome-Encoded Sulfatases

Phase II drug metabolism inactivates xenobiotics and endobiotics through the addition of either a glucuronic acid or sulfate moiety prior to excretion, often via the gastrointestinal tract. While the human gut microbial β-glucuronidase enzymes that reactivate glucuronide conjugates in the intestines are becoming well characterized and even controlled by targeted inhibitors, the sulfatases encoded by the human gut microbiome have not been comprehensively examined. Gut microbial sulfatases are poised to reactivate xenobiotics and endobiotics, which are then capable of undergoing enterohepatic recirculation or exerting local effects on the gut epithelium. Here, using protein structure-guided methods, we identify 728 distinct microbiome-encoded sulfatase proteins from the 4.8 million unique proteins present in the Human Microbiome Project Stool Sample database and 1766 gut microbial sulfatases from the 9.9 million sequences in the Integrated Gene Catalogue. We purify a representative set of these sulfatases, elucidate crystal structures, and pinpoint unique structural motifs essential to endobiotic sulfate processing. Gut microbial sulfatases differentially process sulfated forms of the neurotransmitters serotonin and dopamine, and the hormones melatonin, estrone, dehydroepiandrosterone, and thyroxine in a manner dependent both on variabilities in active site architecture and on markedly distinct oligomeric states. Taken together, these data provide initial insights into the structural and functional diversity of gut microbial sulfatases, providing a path toward defining the roles these enzymes play in health and disease.

Drug-induced endocrine blood pressure elevation

Patients with uncontrolled hypertension are at risk for cardiovascular complications. The majority of them suffers from unidentified forms of hypertension and a fraction has so-called secondary hypertension with an identifiable cause. The patient's medications, its use of certain herbal supplements and over-the-counter agents represent potential causal factors for secondary hypertension that are often overlooked. The current review focuses on drugs that are likely to elevate blood pressure by affecting the human endocrine system at the level of steroid synthesis or metabolism, mineralocorticoid receptor activity, or by affecting the catecholaminergic system. Drugs with known adverse effects but where benefits outweigh their risks, drug candidates and market withdrawals are reviewed. Finally, potential therapeutic strategies are discussed.

Steroid synthesis by Taenia crassiceps WFU cysticerci is regulated by enzyme inhibitors

Cysticerci and tapeworms from Taenia crassiceps WFU, ORF and Taenia solium synthesize sex-steroid hormones in vitro. Corticosteroids increase the 17β-estradiol synthesis by T. crassiceps cysticerci. T. crassiceps WFU cysticerci synthesize corticosteroids, mainly 11-deoxycorticosterone (DOC). The aim of this work was to investigate whether classical steroidogenic inhibitors modify the capacity of T. crassiceps WFU cysticerci to synthesize corticosteroids and sex steroid hormones. For this purpose, T. crassiceps WFU cysticerci were obtained from the abdominal cavity of mice, pre-cultured for 24h in DMEM+antibiotics/antimycotics and cultured in the presence of tritiated progesterone ((3)H-P4), androstendione ((3)H-A4), or dehydroepiandrosterone ((3)H-DHEA) plus different doses of the corresponding inhibitors, for different periods. Blanks with the culture media adding the tritiated precursors were simultaneously incubated. At the end of the incubation period, parasites were separated and media extracted with ether. The resulting steroids were separated by thin layer chromatography (TLC). Data were expressed as percent transformation of the tritiated precursors. Results showed that after 2h of exposure of the cysticerci to 100 μM formestane, the (3)H-17β-estradiol synthesis from tritiated androstenedione was significantly inhibited. The incubation of cysticerci in the presence of (3)H-DHEA and danazol (100 nM) resulted in (3)H-androstenediol accumulation and a significant reduction of the 17β-estradiol synthesis. The cysticerci (3)H-DOC synthesis was significantly inhibited when the parasites were cultured in the presence of different ketoconazole dosis. The drug treatments did not affect parasite's viability. The results of this study showed that corticosteroid and sex steroid synthesis in T. crassiceps WFU cysticerci can be modified by steroidogenic enzyme inhibitors. As was shown previously by our laboratory and others, parasite survival and development depends on sex steroids, therefore the inhibition of their synthesis is a good starting point exploited in situations where the inhibition of steroidogenesis could help to control the infection for the development of new treatments, or replacement of the usual therapy in resistant parasite infections. We raise the possibility that these drug actions may be beneficially.

Danazol inhibits aromatase activity of endometriosis-derived stromal cells by a competitive mechanism

OBJECTIVE

To evaluate the inhibitory effect of danazol on estrogen (E) production in endometriosis.

DESIGN

Prospective randomized study.

SETTING

Academic research unit of the department of obstetrics and gynecology in a university hospital.

PATIENT(S)

Thirteen patients with endometriosis.

INTERVENTION(S)

Danazol was added to the culture of endometriosis-derived stromal cells or suspensions of microsomes prepared from chocolate cysts.

MAIN OUTCOME MEASURE(S)

The aromatase activities as well as mRNA and protein levels of aromatase in endometriosis-derived stromal cells or microsomes of endometriosis were examined.

RESULT(S)

Danazol treatment with a concentration greater than 10(-6) M significantly suppressed aromatase activity of endometriosis-derived stromal cells under basal and prostaglandin E(2) (PGE(2))-stimulated conditions. Danazol (10(-5) M) did not affect mRNA and protein levels of aromatase. Danazol competitively inhibited aromatase activity (by 1.7 x 10(-6) M of calculated Ki and 2.9 x 10(-5) M of Ki') of endometriosis microsomes.

CONCLUSION(S)

Danazol competitively inhibited aromatase activity in endometriosis-derived stromal cells without affecting either the mRNA or protein levels of aromatase. These results indicate the efficacy of local application of danazol to endometriotic lesions.

A benefit-risk assessment of medical treatment for uterine leiomyomas

The growth of a uterine leiomyoma growth stops and regresses after the menopause suggesting that leiomyoma growth is dependent on ovarian steroids. Therefore, estrogen has received much attention as the major factor responsible for the development of uterine leiomyomas, but progesterone also plays an important role in development of this disease. Cytogenetic analyses of resected samples has revealed that about 40 to 50% of leiomyomas show karyotypically detectable chromosomal abnormalities. Gonadotrophin releasing hormone (GnRH) agonists exert their action through the suppression of endogenous gonadotrophins and gonadal steroid secretion. Significant reductions of uterine/leiomyoma volume under GnRH agonist therapy has been reported in several studies. However, the leiomyoma generally returns to its pretreatment volume within a few months after discontinuation of the GnRH agonist. To minimise the adverse effects of hypoestrogenism during GnRH agonist treatment, add back therapy can be used (estrogen-progestin, progestin alone and recently tibolone). Antiprogestins have a potential clinical utility in uterine leiomyomas. Mifepristone is a synthetic steroid with both antiprogesterone and antiglucocorticoid activities, that may have an inhibitory effect on growth of leiomyoma. Danazol is an isoxazole of 17beta-ethinyl testosterone, a synthetic steroid, which has a suppressive effect on sex hormone binding globulin concentrations, resulting in efficacy in the short-term treatment of uterine leiomyomas. Gestrinone is a tri-enic steroid with antiestrogen and antiprogesterone properties and has been shown to reduce uterine volume and stop bleeding. Growth factors play a relevant role on the pathophysiology of uterine leiomyoma and probably the inhibition of the action of growth factors on the myometrium will be the basis for future therapy. A number of agents are under investigation for treating uterine leiomyoma. Agents developed from increasing genetic knowledge of this condition could represent, in the next few years, new trends in the medical treatment of uterine leiomyomas.

Endometriosis of the urinary tract

Genitourinary endometriosis is a rare manifestation of a common disease. Ectopic endometrial tissue may extrinsically involve or intrinsically invade the bladder or ureter, and, less commonly, the urethra or kidney. Bladder involvement usually presents with irritative symptoms, whereas ureteral disease may present with asymptomatic renal failure. Therefore, a high index of suspicion is necessary, and genitourinary endometriosis should be considered in all symptomatic women with a history of cesarean delivery of other gynecologic surgery. In women beyond reproductive age, definitive surgical treatment is preferred, with removal of the ectopic tissue, relief of obstruction, and castration with or without hysterectomy. In those who desire future fertility, conservative surgery and/or hormonal therapy is often recommended.

Inhibition of progesterone secretion with trilostane for mid-trimester termination of pregnancy: randomized controlled trials

BACKGROUND

Progesterone is central to the maintenance of pregnancy, and is thus the ideal target for fertility regulation. Two mechanisms by which progesterone can be targeted are: receptor blockade and reduction of progesterone production through enzyme inhibition. Mifepristone, a receptor blocker, is usually given as 'pretreatment' prior to prostaglandin administration in mid-trimester termination of pregnancy (TOP). Unfortunately, there are difficulties accessing mifepristone in developing countries, and TOP is therefore performed using prostaglandins alone, which results in unacceptably long induction-to-abortion intervals. Trilostane is a 3beta-hydroxysteroid dehydrogenase inhibitor which reduces progesterone production. In these mid-trimester studies it is evaluated as a method of pretreatment prior to misoprostol administration.

METHODS

Three consecutive randomized controlled trials comparing different trilostane regimens for pretreatment were performed. In study 1, trilostane was compared with placebo; in study 2, two doses of trilostane were compared (1080 mg and 720 mg); in study 3, the effect of adding danazol to trilostane as combination therapy was evaluated. The primary outcome in all the studies was the induction-to-abortion interval. Serum progesterone, estradiol and cortisol were measured serially during treatment.

RESULTS

In study 1, 48 women were randomized. The median induction-to-abortion interval was 9 h in the trilostane group and 18.5 h in the placebo group (P < 0.0001). Progesterone and estradiol production was significantly reduced in the women receiving trilostane, with maintenance of diurnal cortisol variation. Twenty-eight women were randomized in study 2, which demonstrated that there was no significant difference in the induction-to-abortion interval using 1080 mg and 720 mg trilostane when compared with the higher doses used in study 1. Study 3, in which 40 women were included, failed to show any additional benefit using combination therapy with danazol and trilostane.

CONCLUSIONS

Trilostane is an effective pretreatment agent in mid-trimester TOP.

Danazol for pelvic pain associated with endometriosis

BACKGROUND

Endometriosis is defined as the presence of endometrial tissue (stromal and glandular) outside the normal uterine cavity. Conventional medical and surgical treatments for endometriosis aim to remove or decrease deposits of ectopic endometrium. The observation that hyperandrogenic states (an excess of male hormone) induce atrophy of the endometrium has led to the use of androgens in the treatment of endometriosis. Danazol is one of these treatments used. The efficacy of danazol is based on its ability to produce a high androgen/low estrogen environment (a pseudo menopause) which results in the atrophy of endometriotic implants and thus an improvement in painful symptoms.

OBJECTIVES

To determine the effectiveness of danazol compared to placebo or no treatment in the treatment of the symptoms and signs, other than infertility, of endometriosis in women of reproductive age.

SEARCH STRATEGY

The Menstrual Disorders Group search strategy was used to identify randomised controlled trials of the use of danazol in endometriosis. In addition, all reference lists of included trials were searched, and relevant drug companies were contacted for details of unpublished trials

SELECTION CRITERIA

Randomised controlled trials in which danazol (alone or as adjunctive therapy) was compared to placebo or no therapy. Trials which only reported infertility outcomes were excluded.

DATA COLLECTION AND ANALYSIS

Only four trials met the inclusion criteria and two authors extracted data independently from these trials. All four trials compared danazol to placebo. Two trials used danazol as sole therapy and two trials used danazol as an adjunct to surgery. Although the main outcome was pain improvement other data relating to laparoscopic scores and hormonal parameters were also collected.

MAIN RESULTS

Treatment with danazol (including adjunctive surgical therapy) was effective in relieving painful symptoms related to endometriosis when compared to placebo. Laparoscopic scores were improved with danazol treatment (including adjunctive therapy) when compared with either placebo or no treatment. Side effects were more commonly reported in those patients receiving danazol than placebo.

REVIEWER'S CONCLUSIONS

Danazol is effective in treating the symptoms and signs of endometriosis. However, its use is limited by the occurrence of androgenic side effects.

Evaluation and management of chronic pelvic pain

Evaluating patients with chronic pelvic pain is complex. A detailed medical history should be ideally supplemented by psychologic evaluation and assessment of the woman's social background. At the time of physical examination, the location and intensity of the pain should be mapped. Assessment of pain relief with the administration of a local anesthetic to trigger points or selected nerves may be useful in predicting the potential efficacy of surgical interventions such as uterosacral nerve ablation. Appropriate tests include pelvic ultrasound and magnetic resonance imaging. Ultimately, laparoscopy may provide the final diagnosis. Management should address the underlying cause(s) of pain; when this cannot be done, it should focus on treating the pain itself. When appropriate, empiric administration of antidepressants may be considered. In selected women, therapeutic goals may be achieved by electrical stimulation of nerves.

Danazol concentrations in ovary, uterus, and serum and their effect on the hypothalamic-pituitary-ovarian axis during vaginal administration of a danazol suppository

OBJECTIVE

To determine danazol concentrations in the ovary, uterus, and serum during daily vaginal administration of a danazol suppository and to examine its effect on the hypothalamic-pituitary-ovarian axis.

DESIGN

Sampling of tissues after vaginal or oral administration of danazol and sampling of blood during control and danazol-administration menstrual cycles.

SETTING

Outpatient volunteers and inpatients at a public hospital.

PARTICIPANTS

Thirty patients who were to undergo hysterectomy and oophorectomy because of uterine leiomyoma and eight regularly menstruating volunteers.

INTERVENTIONS

Danazol was administered as a vaginal suppository (100 mg) or orally (400 mg).

MAIN OUTCOME MEASURE

Danazol concentrations in the ovary, uterus, and serum, and serum E2 and P levels.

RESULTS

Danazol concentrations in the ovary and uterus after daily vaginal administration of a suppository containing 100 mg danazol were comparable to those after daily oral administration of 400 mg danazol, but the serum danazol concentration was much lower. Menstrual cycle patterns of serum E2 and P levels were normal during daily vaginal administration of a danazol suppository.

CONCLUSION

Daily administration of a suppository containing 100 mg danazol produces high ovarian and uterine concentrations but low serum concentrations, and no effect was detected on the hypothalamic-pituitary-ovarian axis.

Leukocyte subpopulation changes in rats with autotransplanted endometrium and the effect of danazol

PROBLEM

This study examines immune cell populations in rats with autotransplanted endometrium and determines the effect of danazol on leukocyte subsets.

METHODS

As an experimental model of endometriosis, an autologous endometrial segment was implanted in the rat peritoneum. We used flow cytometry to analyze lymphocyte subsets in the peripheral blood (PB) and peritoneal fluid (PF) of the following groups of rats: no treatment, sham operation, endometrial implantation, endometrial implantation treated with danazol, and normal rats treated with danazol.

RESULTS

The natural killer (NK) cell population was decreased in both the PB and PF of rats with autotransplanted endometrium. Moreover, NK cells increased in a dose-dependent manner following danazol administration. Surgery itself increased the number of peritoneal macrophages as compared with the untreated group. This elevation was suppressed partially by endometrium-implantation and was attenuated by subsequent administration of danazol in a dose-dependent fashion.

CONCLUSIONS

These data suggest that ectopic endometrial cells may release immunosuppressive factors. This is the first documentation that rats with autotransplanted endometrium show the same immunologic changes as humans with endometriosis, and establishes the utility of this model for the study of endometriosis.

Evidence for estrogen synthesis in adenomyotic tissues

OBJECTIVE

To investigate steroidogenesis in eutopic and ectopic endometrial tissues in adenomyosis.

STUDY DESIGN

Aromatase and estrone sulfatase activities were determined by anion-exchange resin column chromatography, thin-layer chromatography, and cocrystallization. The effects of danazol on the activity of these enzymes were also examined. Moreover, localization of aromatase in eutopic and ectopic endometrial tissues was immunohistochemically examined with antihuman placental aromatase cytochrome P-450 antibody.

RESULTS

Aromatase and estrone sulfatase activities were detected in ectopic endometrium. The activity of these enzymes was significantly suppressed by danazol. In addition, aromatase was immunohistochemically detected in glandular cells of eutopic and ectopic endometrial tissues.

CONCLUSIONS

The results suggest that estrogen is synthesized in the eutopic and ectopic endometrial tissues of women with uterine adenomyosis and that it may affect the growth of adenomyosis. Danazol suppressed synthesis of estrogen in vitro.

Mitogen induced production of polyclonal IgG is decreased in women with severe endometriosis

PROBLEM

The etiology and/or pathogenesis of endometriosis may involve aspects of both humoral and cellular immunity.

METHOD

In this investigation, we analyzed the ability of B lymphocytes from distinct patient groups for production of IgG1, IgG2, and IgG3 following in vitro stimulation with polyclonal B-cell mitogens (pokeweed mitogen and Staphylococcus aureus Cowan strain I) after in vitro stimulation with polyclonal B-cell activators.

RESULTS

We observed that the in vitro production of IgG1, IgG2, and IgG3 was identical among fertile controls (no endometriosis; N = 22), infertile women without endometriosis (N = 22), infertile women without endometriosis (N = 20) and patients with stage 1 or 2 endometriosis (N = 31). In contrast, in vitro IgG2 production was significantly reduced among women with stage 3 or 4 endometriosis (N = 11) compared to controls (P < 0.001).

CONCLUSION

Since the number of circulating B cells was similar in each patient group studied, the reduced production of IgG2 in patients with stage 3 or 4 disease was not merely due to fewer antibody producing cells in those subjects, and we speculate that the observed decrease in polyclonal IgG2 production among these patients is due to a primary defect. In additional studies, we observed that polyclonal IgG2 production was normal among stage 3 or 4 patients treated with danazol (N = 11), but significantly reduced in patients treated with gonadotropin releasing hormone agonists (N = 8). Although not conclusive, these data suggest that danazol may have the capacity to correct the defective production of polyclonal IgG2 in patients with severe endometriosis.

The effects of fetal exposure to danazol

OBJECTIVE

To assess the consequences of exposure to danazol in utero. Additionally, by assessing the risk, to facilitate the counselling of pregnant women inadvertently exposed to danazol in early pregnancy.

DESIGN

Retrospective review of reported case histories.

SUBJECTS

129 women exposed to danazol during pregnancy were identified from individual case reports, data from the Australian Drug Reactions Advisory Committee and the United States Food and Drug Administration and from the reports of danazol exposure made directly to the manufacturers.

MAIN OUTCOME MEASURES

Teratogenic effects of fetal exposure to danazol in relation to dosage and duration of exposure.

RESULTS

Of the 129 reported pregnancies, 12 miscarried and 23 were aborted. Of the 94 completed pregnancies, 37 resulted in the birth of normal males, 34 in non-virilized females and 23 in virilized females. Virilization occurred in a proportion of female fetuses with a pattern of cliteromegaly, fused labia and urogenital sinus formation. Surgery to the genital tract was usually, but not always, required in childhood. The abnormality has not been reported where danazol therapy had been discontinued before the 8th week of pregnancy. Although more common in the higher dosages, virilization was reported in one case with a 200 mg daily dosage.

CONCLUSIONS

Danazol should remain contraindicated in pregnancy and clinicians should give careful contraceptive advice to patients commencing or continuing danazol therapy. Nonetheless it is possible to be cautiously optimistic about the outcome of danazol-exposed pregnancies, particularly if treatment is discontinued before 8 completed weeks gestation.

Effects of an androgenic derivative on pre-established mammary tumours chemically induced in the rat

The effects were studied of an androgenic derivative--danazol--administered at doses of 10-12 mg kg-1 day-1 during 97 days to rats with dimethylbenz[a] anthracene-induced mammary tumours. Our main observations were as follows. (a) Danazol did not influence ovarian function at the end of the assay. (b) The treatment with danazol reduced the incidence (P less than 0.05), number of tumours (P less than 0.05) and volume of malignant mammary tumours; on the other hand, the values of these parameters for benign tumours and those of doubtful expression were similar in both experimental groups. (c) Such differential action of Danazol seems to be due to the different incidence and/or content of receptors of both types of tumours. (d) The latter results lead to a hypothesis for the mechanism of action of danazol based on its behaviour at different levels.

The effect of danazol on pulsatile gonadotropin secretion in women with endometriosis

OBJECTIVE

To determine whether the effect of danazol on gonadotropin pulsatility was due to a direct effect of the drug or the suppression in the estradiol (E2) levels.

DESIGN

Prospective analysis of serial blood samples at 10-minute intervals for 5 hours on days 3, 4, or 5 of the control cycle and 2 months after the start of danazol treatment.

SETTING

Tertiary institutional outpatient care.

PATIENTS, PARTICIPANTS

Six eugonadal women with minimal endometriosis.

INTERVENTIONS

Oral administration of danazol, 200 mg three times daily.

MAIN OUTCOME MEASURES

Gonadotropin mean levels, pulse frequency, and amplitude.

RESULTS

The mean level of E2 was the same in the control cycle as that during danazol treatment (170 pmol/L). Danazol administration resulted in a 16% increase in the mean luteinizing hormone (LH) pulse amplitude (95% confidence interval [CI] 6% to 26%, P less than 0.01), associated with a 20% decrease in LH pulse frequency (95% CI -71% to +31%, P = 0.37). There was a nonsignificant increase in follicle-stimulating hormone (FSH) pulse amplitude (2%, 95% CI -9% to +14%, P = 0.68) and in FSH pulse frequency (27%, 95% CI -4% to +58%, P = 0.08). The 22% decrease in the mean LH level (95% CI -85% to +12%, P = 0.13) and the 20% decrease in the mean FSH level (95% CI -53% to +37%, P = 0.33) were also not significant.

CONCLUSIONS

The increase in LH pulse amplitude represents a direct effect of danazol on the hypothalamic-pituitary axis.

The effect of danazol and the LHRH agonist analogue goserelin (Zoladex) on the biological activity of luteinizing hormone in women with endometriosis

In an attempt to determine whether the suppression in oestradiol levels caused by danazol is due to an effect on the hypothalamic-pituitary axis, we compared the endocrine effects of danazol with those of the LHRH (GnRH) agonist analogue goserelin. Serum levels of immunoreactive LH (I-LH), FSH, 17 beta-oestradiol (E2) and bioactive LH (B-LH) (using a mouse Leydig cell bioassay), were measured in ten and 20 women with endometriosis treated with danazol and goserelin, respectively. I-LH was measured both by radioimmunoassay (RIA) and immunoradiometric assay (IRMA). During 6 months of treatment with 600 mg of danazol daily, mean serum E2 decreased (P less than 0.05) to levels near the upper limit of the post-menopausal range (to a mean (and 95% confidence interval of the mean) of 117 (65-169) pmol/l) whereas FSH, I-LH (both by RIA and IRMA) and B-LH levels were not significantly altered. During 6 months of treatment with monthly depot injections of 3.6 mg goserelin, mean serum E2 decreased (P less than 0.001) to well within the post-menopausal range (to 23 (18-28) pmol/l). The mean FSH, I-LH and B-LH levels also decreased (P less than 0.05) during therapy with goserelin (from 3.9 (3.1-4.7) to 2.0 (1.6-2.4) IU/l for FSH, from 5.3 (4.5-6.1) to 1.9 (1.7-2.1) IU/l for RIA-LH, from 2.9 (2.5-3.3) to less than 0.5 (less than 0.5) IU/l for IRMA-LH and from 9.1 (7.1-11.1) to 2.9 (2.6-3.2) IU/l for B-LH).(ABSTRACT TRUNCATED AT 250 WORDS)

Placebo-controlled comparison of hormonal and biochemical effects of danazol and high-dose medroxyprogesterone acetate

The hormonal and biochemical effects of danazol (600 mg a day) and high-dose medroxyprogesterone acetate (MPA; 100 mg a day) were studied in a placebo-controlled, 6-month trial. Serum gonadotrophins and prolactin levels did not change during danazol and MPA treatments, whereas oestradiol and progesterone levels decreased significantly in relation to placebo without any difference between danazol and MPA. Both drugs significantly suppressed the sex hormone-binding globulin level (SHBG), and consequently, the free-androgen index (serum total testosterone nmol/l per SHBG nmol/l x 100) as compared with placebo, the effect of danazol being significantly stronger than that of MPA. Danazol, but not MPA, significantly increased serum aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT) and haemoglobin levels, and also thrombocyte counts, whereas MPA, but not danazol, increased the serum concentration of albumin in relation to placebo. Serum total bilirubin, conjugated bilirubin, gamma-glutamyl transferase, creatinine, alkaline phosphatase, sodium and potassium levels and leucocyte counts remained unchanged during both treatments. Danazol and high-dose MPA did not differ from each other in their ovarian and anterior pituitary effects, while the increase in androgenic activity induced by danazol was greater than that achieved with MPA. Danazol also had more biochemical effects than MPA. It interfered with the functions of the liver and the production of thrombocytes and haemoglobin, whereas MPA affected only albumin synthesis/release.

Comparison of the pharmacology of nafarelin and danazol

The pharmacologic profiles of danazol and nafarelin differ considerably from each other. Danazol interacts with multiple classes of proteins, whereas the gonadotropin-releasing hormone agonist nafarelin interacts only with the pituitary gonadotropin-releasing hormone receptor. Differences in the molecular, endocrine, and clinical pharmacologic properties of these agents may provide clues to their varying effects in the management of women with endometriosis.

Sustained azoospermia in squirrel monkey, Saimiri sciureus, resulting from a single intratesticular glycerol injection

Previous studies in rats had shown that a single intratesticular injection of glycerol resulted in long-term suppression of spermatogenesis without marked alterations in hormone levels. Studies were undertaken to determine the effect of similar treatment in squirrel monkeys (Saimiri sciureus). Ten monkeys received an intratesticular injection of saline (controls) and ten of glycerol solution (treated). Semen and blood samples were obtained on a weekly or bi-weekly basis one month prior to, during the 8 months following and at 22 months after the injection. Sperm numbers in the semen samples of controls remained at 160-435 x 10(6) per ml throughout the experiment. Sperm numbers in treated animals declined to near zero within two months and remained at zero. Serum testosterone and progesterone levels were not significantly different between control and treated animals. Serum LH and FSH levels were not significantly different between control and treated animals except during months 6-8 after the injection, when levels in the treated were higher. At termination (22 months), the weights and sperm contents of epididymides of the glycerol-treated animals were highly significantly reduced. Steroidogenesis (based on amounts and kinds of steroids formed from 14C-progesterone) by testicular tissue was not altered by the glycerol treatment when measured on a per testis basis. This is the first evidence that a single intratesticular injection of glycerol results in long-term suppression of spermatogenesis in primates, without altering testicular steroidogenesis and serum hormone levels.

A randomized, prospective comparison of endocrine changes induced with intranasal leuprolide or danazol for treatment of endometriosis

A prospective, randomized trial compared hormonal changes induced with intranasal leuprolide 1.6 mg/day to danazol 800 mg/day for treatment of endometriosis. Both regimens induced anovulation and ovarian suppression in all subjects. Mean estradiol (E2) and progesterone (P) levels were suppressed with both regimens, but were lower with leuprolide. There was no difference in cumulative follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels, although at times during treatment mean levels of these hormones were lower with leuprolide. Higher P levels in the danazol group, most likely of adrenal origin, indicated a suppressive effect on adrenal steroidogenesis. Symptomatic improvement was significant in both groups. Laparoscopy after treatment also demonstrated a decrease in endometriosis scores in both groups. At 12 months after treatment, cumulative pregnancy and live birth rates were similar in both groups. Leuprolide offers an attractive alternative to danazol for the medical treatment of endometriosis.

Plasma and peritoneal fluid levels of CA 125 in women with endometriosis

Determined by a sandwich, solid-phase radioimmunoassay with mouse monoclonal antibody, OC 125, plasma CA 125 levels were significantly elevated in stage III (mean +/- SEM = 32.7 +/- 5.2 U/ml, n = 17, p = less than 0.01) and stage IV endometriosis (37.2 +/- 10.5 U/ml, n = 6, p = less than 0.005) compared with levels during the follicular (15.9 +/- 1.5 U/ml, n = 12) and secretory phases (15.8 +/- 1.3 U/ml, n = 15) of control women and users of oral contraceptives (15.5 +/- 1.2 U/ml n = 10). However, CA 125 levels were not significantly elevated in women with stage I (16.6 +/- 2.0 U/ml, n = 28) or stage II endometriosis (17.9 +/- 2.1 U/ml, n = 13). Peritoneal fluid levels of CA 125 (n = 14) were significantly higher (2 to 9.3 times) than the corresponding paired plasma levels in participants with stage I, II, or III endometriosis. In patients treated with danazol (n = 10) or buserelin (n = 17), plasma CA 125 levels decreased significantly by midtherapy, remained suppressed at the end of therapy, but rebounded to near pretreatment levels 6 months after treatment was completed. With gestrinone therapy a similar decline was observed but became significant only at the end of therapy. Our findings indicate that elevated plasma CA 125 levels may prove useful in the management of endometriosis.

The treatment of symptomatic benign breast disease with danazol

A prospective randomized double blind trial, using danazol in a dose of 200 mg twice a day, was carried out on 80 women presenting with severe cyclical symptomatic benign mammary dysplasia. Standardized scores for 4 parameters of disease severity (breast pain, breast tenderness, breast nodularity and breast cysts) were defined and measured monthly on all patients admitted to the trial. Using nonparametric statistical analysis, significant improvement in breast pain, tenderness and nodularity, was found in both the double blind and crossover arms of the trial. An insufficient number of patients presented with breast cysts to draw any conclusions regarding the efficacy of danazol on cysts. Six months of treatment may produce a more sustained response, than 3 months of treatment. Danazol appears to be efficacious in managing patients with severe breast symptoms due to benign disease.

Effects of danazol, gonadotropin-releasing hormone agonist, and estrogen/progestogen combination on experimental endometriosis in the ovariectomized rat

Direct effects of a gonadotropin-releasing hormone agonist (GnRHa), danazol, or estrogen/progestogen (E/P) on experimental endometriosis were evaluated in castrated female rats. Endometrial explants decreased in size following castration, but there was no further change in the treatment groups. Histologic examination indicated atrophy and regression of experimental endometriosis in all groups of castrated animals. As expected, following castration, serum estradiol (E2) became undetectable, serum progesterone (P4) decreased, and cytosolic E2 and P4 binding capacity in the endometrial explants was lower. However, in danazol-treated animals, serum P4 and E2 receptor concentrations were significantly higher than in all other castrated groups, and in both danazol and E/P treated animals, concentrations of P4 receptor were significantly higher than in castrated controls. In contrast, GnRHa treatment had no effect on serum E2 and P4 levels nor on E2 or P4 receptors. The authors conclude that danazol and E/P preparations may have a direct effect on the ectopic endometrium through interaction with steroid receptors.

The inhibitory effects of danazol, danazol metabolites, gestrinone, and testosterone on the growth of human endometrial cells in vitro

Danazol and gestrinone are effective drugs in the treatment of endometriosis. Their mechanism of action remains uncertain, but may be related to their androgenic activity. The authors examined the effect of danazol on human endometrial cells cultured in vitro, its two major metabolites, ethisterone and 2 hydroxymethyl ethisterone, gestrinone, and testosterone (T) at 1X and 10X expected plasma concentrations. Danazol and T suppressed growth by 20.8 and 25.0% (P less than 0.01), respectively, at the lower dose, and by 26.9 and 35.5% (P less than 0.01), respectively, at the 10-fold higher dose. No significant suppression of growth occurred with gestrinone, ethisterone, or 2 hydroxymethyl ethisterone. The results provide further evidence that danazol and T (but not gestrinone) may act by a direct effect on endometrial tissue.

Testis functions and sexual potentia in langur monkey treated with a combination steroidal contraceptive formulation

Administration of a combination formulation of danazol (100 mg/day; oral) plus testosterone enanthate (TE) (50 mg/15 days; i.m.) for 30 to 60 days in adult male langur monkeys resulted in the reversible suppression of testicular function without affecting the sexual potentia. Testicular weight and volume decreased significantly along with the mass atrophy of germinal epithelium and impaired morphology of Leydig and Sertoli cells. A conspicuous shrinkage of seminiferous tubules, Leydig cell nuclei and Sertoli cell nuclei was noted. Elevation of testicular cholesterol, total lipids, glycogen and phosphatases activity with the depletion of total proteins, nucleic acid, sialic acid and fructose was noteworthy. All changes were maintained during maintenance dose studies (danazol: 50 mg/day; oral plus TE: 50 mg/15 days; i.m.) for 60 days. Resumption of all measures to normal was evident following 120 days of recovery. It can be concluded that the exogenous TE substitutes the serum testosterone levels to maintain extratesticular androgen actions even after interference by danazol of Leydig cell function along with spermatogenesis inhibition.

Direct biphasic effects of danazol on gonadotropin-dependent differentiation of cultured rat granulosa cells

The direct effects of danazol on granulosa cell differentiation were studied in vitro over a broad concentration range with a primary culture of rat granulosa cells. Whereas treatment with low-dose (defined herein as less than 10(-6) M) danazol by itself was without significant effect on basal steroid secretion, combined treatment with low-dose danazol (10(-7) M) and a minimally effective dose of follicle-stimulating hormone (FSH, 20 ng/ml) resulted in a substantial augmentation of the FSH effect. Although independent of the FSH dose employed, the effect of danazol proved dose- and time-dependent, with an apparent median effective dose of 3.6 +/- 0.3 X 10(-8) M. In contrast, high-dose danazol (defined herein as greater than 10(-6) M) produced dose-dependent inhibition of FSH (250 ng/ml)-supported steroid secretion. Taken together, our findings indicate that the effects of danazol on granulosa cell differentiation may be biphasic in nature, displaying a stimulatory low-dose component, followed by inhibition at higher dose levels.

Relationship of gonadotropin-releasing hormone, danazol, and prostaglandin blockade to ovarian enlargement and ascites formation of the ovarian hyperstimulation syndrome in the rabbit

The effects of pharmacologic doses of gonadotropin-releasing hormone, danazol, and indomethacin on the clinical and endocrinologic features of the ovarian hyperstimulation syndrome were studied in the rabbit. The ovarian hyperstimulation syndrome was induced with Pergonal (75 IU of follicle-stimulating hormone and 75 IU of luteinizing hormone) and a follicle-stimulating hormone-dominant gonadotropin preparation (85 IU of follicle-stimulating hormone and 53 IU of luteinizing hormone). None of the three agents tested were effective in suppressing the ovarian enlargement and ascites formation in these animals. Ascites developed despite quite significant variations in plasma and intraovarian sex steroid hormone and intraovarian prostaglandin F levels induced by danazol and indomethacin. Ascites develops in hyperstimulated women in association with both follicular and luteal hyperstimulation. In contrast, the ascites response in the hyperstimulated rabbit develops in the presence of follicular hyperstimulation alone without a significant degree of luteal hyperstimulation.

Cytoplasmic and nuclear estrogen binding capacity in the rat uterus during treatment with danazol and testosterone

Danazol, testosterone and dihydrotestosterone (DHT) were tested as competitors for estrogen receptors on immature rat uterus cytosol. No competitive binding could be demonstrated for any of these steroids. After that, prepubertal Wistar rats were exposed to danazol, testosterone or propylene glycol (control) for 3 days or 17 days. After the appropriate exposure to medication, the animals were killed. Both danazol and testosterone appeared to be uterotropic after 3 days of treatment, although the increase in the uterine weight was significant only in the danazol-treated group (p less than 0.05). This effect was lost after 17 days of treatment. Estradiol receptor binding assays were done on the cytosolic and nuclear fractions of the homogenized uterine tissue of each group. The estrogen binding capacity of cytosols was increased in both the danazol (p less than 0.05) and the testosterone (p less than 0.01) groups after 3 days of treatment. A parallel increase was found in the nuclear fraction of both groups. After 17 days of treatment, the comparison between the 3 groups showed no differences in the cytosolic or nuclear estrogen binding capacity. The information provided by this study suggests that some effects of danazol may be due to an androgenic action and that may be associated to increases in the free fraction of testosterone.

Effects of danazol on steroidogenesis and gonadotropic responsiveness in isolated human preovulatory follicular cells

In order to investigate the influence of danazol on steroidogenesis and gonadotropic responsiveness of human follicular cells, granulosa and thecal cells of preovulatory follicles were isolated and separately incubated for short term periods. Human chorionic gonadotropin (hCG) (100 IU/ml), FSH (0.5 IU/ml) and danazol (10 micrograms/ml) alone or in combination were added to the incubation medium. Following incubation the cellular cyclic adenosine 3'5' monophosphate (cAMP) levels and the medium content of progesterone (P), androstenedione (A) and 17 beta-estradiol (E2) were determined. All follicles included in the study were classified as nonatretic and well developed, i.e. less than 3 days before ovulation. Human chorionic gonadotropin caused an increase in cAMP formation in both cell-types and this effect was significantly counteracted by danazol in vitro. In granulosa cells danazol tended to counteract a stimulatory effect of FSH on cAMP formation. No significant influence of danazol was found on the basal steroid formation of both cell types during short term incubation. On the other hand, danazol significantly counteracted the FSH stimulated P formation of the granulosa cells and the hCG stimulated A and E2 formation of the thecal cells. It is concluded that danazol inhibits gonadotropin-stimulated steroidogenesis locally in the human follicular cells and that this effect of danazol is mediated via the cyclic AMP system.

Inhibition of gonadotropin-releasing hormone receptors in rat anterior pituitary monolayer cell cultures by danazol

To study possible cellular antigonadotropic effects of danazol, monolayer cultures of anterior pituitary cells from immature female rats were treated with danazol. Measurements of luteinizing hormone release in response to 10(-8) mol/L gonadotropin-releasing hormone challenge and iodine 125-labeled gonadotropin-releasing hormone binding activity were done after exposure to increasing concentrations of danazol and for increasing lengths of time. It was found that luteinizing hormone secreted by pituitary cells in response to gonadotropin-releasing hormone was inhibited after danazol treatment in a dose- and time-dependent manner when compared to controls. Also, a 45% decrease in gonadotropin-releasing hormone receptor binding capacity was observed in pituitary cells cultured in the presence of increasing concentrations of danazol in the range of 10(-8) to 10(-4) mol/L when compared to controls. Furthermore, exposure to danazol for 25 to 96 hours caused a marked decrease in gonadotropin-releasing hormone binding activity (p less than 0.005). Under these experimental conditions danazol treatment decreased the pituitary receptors for gonadotropin-releasing hormone in a dose- and time-dependent manner. Scatchard analysis of saturation curves for the binding of gonadotropin-releasing hormone to cellular gonadotropin-releasing hormone receptors indicated that the observed decrease in gonadotropin-releasing hormone binding in the danazol-treated group was due to a change in the number of gonadotropin-releasing hormone binding sites rather than a change in the affinity. It is therefore concluded that the antigonadotropic activity of danazol appears to be related to a decrease in gonadotropin-releasing hormone receptors in the pituitary.

Danazol treatment of advanced prostate cancer: clinical and hormonal effects

Danazol was administered to 19 patients with advanced prostate cancer. These patients were treated for periods ranging from 3 days to 18 weeks. There were no objective remissions, but three patients (15.8%) had objectively stable disease (N.P.C.P. criteria) with complete pain control for periods ranging 15-18 weeks. Seven patients experienced tumor flare reactions, one requiring withdrawal of treatment and one resulting in rapid clinical deterioration and death. Four other patients died within 3 weeks and, although they were already in the terminal phase of disease when treatment commenced, it is possible that the deaths were treatment related. This study indicates that danazol has only limited activity in the treatment of advanced prostate cancer and is associated with a high incidence of tumor flare reactions with the risk of rapid clinical deterioration.

Danazol and fetal masculinization: a warning

Masculinization of a female fetus occurred during a pregnancy in which the mother received danazol for infertility due to endometriosis. The biochemical theories and the necessary treatment are outlined. Conception may occur before or during a course of danazol, and patients should be made aware of the need for concomitant contraception.

Changes in the biochemical composition of semen following danazol plus testosterone enanthate administration to the langur monkey

Changes in the biochemical composition of semen, which reflect the accessory sex organ functions, following danazol (100 mg/day; orally) plus testosterone enanthate (50 mg/month; i.m.) administration have been investigated in langur monkey. The levels of acid phosphatase, lactic dehydrogenase and glycerylphosphorylcholine in the semen decreased significantly; whereas fructose, citric acid, magnesium and semen volume did not show any significant changes. A gradual decrease in the motility and count of spermatozoa was observed. At 60 days of treatment all animals became azoospermic. No drug related hematological changes were observed. The combination therapy impaired the epididymal and prostatic functions along with suppression of spermatogenesis.

Serum estradiol and danazol. I. Endometriosis response, side effects, administration interval, concurrent spironolactone and dexamethasone

Serum estradiol (E2) levels and resolution of endometriosis were evaluated in 42 women after 75 days of danazol treatment. Complete or almost complete remission occurred when radioimmunoassay E2 levels were less than 15 pg/ml in extensive, less than 22 pg/ml in severe, and less than 41 pg/ml in moderate endometriosis. E2 less than or equal to 20 pg/ml occurred in 23% of 104 patients given 400 mg every 12 hours but in none weighing over 150 pounds (68 kg). E2 greater than 100 pg/ml occurred in 7%. The mean E2 levels were identical with 400 mg every 12 hours and 200 mg every 8 hours. The E2 level was 40% lower with 200 mg every 6 hours than with 400 mg every 12 hours (P less than 0.001). Dexamethasone further decreased E2 levels by 61% (P less than 0.001). Spironolactone decreased androgen symptoms but increased E2 levels by 49% (P less than 0.01).

Reversible inhibition of spermatogenesis by danazol with combination of testosterone enanthate in rabbit

Danazol (15 mg/kg b.w./day; oral) with combination of testosterone enanthate (5 mg/kg b.w./15 days; S.C.) was tested in male rabbits for reversible suppression of spermatogenesis. Semen analyses for efficacy and reversibility were performed biweekly. The regimen resulted in complete azoospermia or severe oligozoospermia in all the animals within 75 days of treatment accompanied with decreased motility, vitality and increased sperm abnormalities. Semen volume and pH did not alter significantly. Libido was unaffected. All seminal characteristics were within normal range after 115 days of recovery. In conclusion, the drug combination in given dose regimen resulted in reversible inhibition of spermatogenesis in rabbits.

Inhibition of human placental progesterone synthesis by danazol in vitro

In vitro, danazol showed a slight dose-dependent inhibition of the mitochondrial cholesterol side chain cleavage enzyme isolated from early gestational (8th to 12th week of gestation) placenta. In the presence of 100 microM danazol, the enzyme activity was 65% of controls. Danazol inhibits dose-dependently the mitochondrial 3 beta-hydroxysteroid dehydrogenase (I50 = 3.1 microM; Ki = 1 microM) (noncompetitive inhibition) and the cytoplasmic 20 alpha-hydroxysteroid dehydrogenase (I50 = 1.4 microM; Ki = 2.6 microM) (competitive inhibition). The inhibition of human placental progesterone synthesis by danazol in vitro is a further example for the direct interference of danazol with steroidogenesis.

The interaction of human endometrial and myometrial steroid receptors with danazol

The affinity of danazol for oestrogen, androgen and progesterone receptors in human endometrium and myometrium was determined, to study the mechanism of action of this drug in the treatment of endometriosis. The ability of danazol to combine with each of the three types of receptor was similar in both endometrium and myometrium. The capacity of danazol to compete with oestradiol-17 beta for the oestrogen receptor was very low (1.72 +/- 0.48 X 10(-3%) cross reaction, mean +/- SEM) and danazol, at the maximum concentration used, was unable to saturate the receptor; but danazol's ability to compete with progesterone for its receptor was considerably higher (8.41 +/- 1.65% using progesterone, 1.95 +/- 0.41% using R5020) and was saturable. Danazol was also able to displace dihydrotestosterone from the cytosol androgen receptor (6.29 +/- 1.82% cross reaction). The association constant of oestradiol for the endometrial and myometrial oestrogen receptors was 2.19 X 10(9)M-1 and 7.45 X 10(9)M-1 respectively, while that of progesterone and dihydrotestosterone for their receptors was similar in endometrium and myometrium (mean 0.25 +/- 0.06 X 10(9) M-1 and 3.62 +/- 1.67 X 10(9) M-1 respectively). Using R5020, the association constant for the myometrial progesterone receptor was 2.50 +/- 0.73 X 10(9) M-1. We conclude that, in view of the high circulating levels of danazol present in patients being treated for endometriosis, it is possible that danazol may bind to, and partly saturate, endometrial and myometrial oestrogen, progesterone and androgen receptors during treatment. An explanation may thus be provided for some of the diverse actions of this drug.