English, Robert S
2018-02-01
Androgenic alopecia, also known as pattern hair loss, is a chronic progressive condition that affects 80% of men and 50% of women throughout a lifetime. But despite its prevalence and extensive study, a coherent pathology model describing androgenic alopecia's precursors, biological step-processes, and physiological responses does not yet exist. While consensus is that androgenic alopecia is genetic and androgen-mediated by dihydrotestosterone, questions remain regarding dihydrotestosterone's exact role in androgenic alopecia onset. What causes dihydrotestosterone to increase in androgenic alopecia-prone tissues? By which mechanisms does dihydrotestosterone miniaturize androgenic alopecia-prone hair follicles? Why is dihydrotestosterone also associated with hair growth in secondary body and facial hair? Why does castration (which decreases androgen production by 95%) stop pattern hair loss, but not fully reverse it? Is there a relationship between dihydrotestosterone and tissue remodeling observed alongside androgenic alopecia onset? We review evidence supporting and challenging dihydrotestosterone's causal relationship with androgenic alopecia, then propose an evidence-based pathogenesis model that attempts to answer the above questions, account for additionally-suspected androgenic alopecia mediators, identify rate-limiting recovery factors, and elucidate better treatment targets. The hypothesis argues that: (1) chronic scalp tension transmitted from the galea aponeurotica induces an inflammatory response in androgenic alopecia-prone tissues; (2) dihydrotestosterone increases in androgenic alopecia-prone tissues as part of this inflammatory response; and (3) dihydrotestosterone does not directly miniaturize hair follicles. Rather, dihydrotestosterone is a co-mediator of tissue dermal sheath thickening, perifollicular fibrosis, and calcification - three chronic, progressive conditions concomitant with androgenic alopecia progression. These conditions remodel
Dadras, Soheil S.; Cai, Xiaoyan; Abasolo, Ibane; Wang, Zhou
2001-01-01
The growth and development of some of the male sex accessory organs such as the prostate requires the conversion of testosterone to dihydrotestosterone (DHT) by 5α-reductase. To provide insights into the role of testosterone versus DHT in the prostate, we studied the impact of finasteride, a potent and specific inhibitor of 5α-reductase, on the expression of prostatic androgen-response genes in testis-intact rats and in 7-day castrated rats. Finasteride inhibition of the conversion of testosterone to DHT was confirmed by measuring serum and intraprostatic androgens. As expected, finasteride treatment caused a reduction in the wet weight of the prostate in the testis-intact rats and inhibited the testosterone-stimulated prostatic regrowth in the 7-day castrated rats. Although finasteride treatment had little or no effect on the expression of the surveyed androgen-response genes in testis-intact rats, its administration enhanced the expression of many androgen-response genes during the testosterone-stimulated regrowth of the regressed prostate in castrated rats. These observations suggest that testosterone is more potent than DHT in stimulating the expression of many androgen-response genes in the regressed prostate. The expression of androgen-response genes is mainly prostate specific and thus is likely to be associated with androgen-dependent prostatic differentiation. Therefore, testosterone is more potent than DHT in inducing differentiation and weaker in stimulating proliferation during prostate regrowth. The fact that testosterone is a strong inducer of prostatic differentiation has potential clinical implications. PMID:11444528
Okamoto, Masahiro; Hojo, Yasushi; Inoue, Koshiro; Matsui, Takashi; Kawato, Suguru; McEwen, Bruce S; Soya, Hideaki
2012-08-07
Mild exercise activates hippocampal neurons through the glutamatergic pathway and also promotes adult hippocampal neurogenesis (AHN). We hypothesized that such exercise could enhance local androgen synthesis and cause AHN because hippocampal steroid synthesis is facilitated by activated neurons via N-methyl-D-aspartate receptors. Here we addressed this question using a mild-intense treadmill running model that has been shown to be a potent AHN stimulator. A mass-spectrometric analysis demonstrated that hippocampal dihydrotestosterone increased significantly, whereas testosterone levels did not increase significantly after 2 wk of treadmill running in both orchidectomized (ORX) and sham castrated (Sham) male rats. Furthermore, analysis of mRNA expression for the two isoforms of 5α-reductases (srd5a1, srd5a2) and for androgen receptor (AR) revealed that both increased in the hippocampus after exercise, even in ORX rats. All rats were injected twice with 5'-bromo-2'deoxyuridine (50 mg/kg body weight, i.p.) on the day before training. Mild exercise significantly increased AHN in both ORX and Sham rats. Moreover, the increase of doublecortin or 5'-bromo-2'deoxyuridine/NeuN-positive cells in ORX rats was blocked by s.c. flutamide, an AR antagonist. It was also found that application of an estrogen receptor antagonist, tamoxifen, did not suppress exercise-induced AHN. These results support the hypothesis that, in male animals, mild exercise enhances hippocampal synthesis of dihydrotestosterone and increases AHN via androgenenic mediation.
Okamoto, Masahiro; Hojo, Yasushi; Inoue, Koshiro; Matsui, Takashi; Kawato, Suguru; McEwen, Bruce S.; Soya, Hideaki
2012-01-01
Mild exercise activates hippocampal neurons through the glutamatergic pathway and also promotes adult hippocampal neurogenesis (AHN). We hypothesized that such exercise could enhance local androgen synthesis and cause AHN because hippocampal steroid synthesis is facilitated by activated neurons via N-methyl-D-aspartate receptors. Here we addressed this question using a mild-intense treadmill running model that has been shown to be a potent AHN stimulator. A mass-spectrometric analysis demonstrated that hippocampal dihydrotestosterone increased significantly, whereas testosterone levels did not increase significantly after 2 wk of treadmill running in both orchidectomized (ORX) and sham castrated (Sham) male rats. Furthermore, analysis of mRNA expression for the two isoforms of 5α-reductases (srd5a1, srd5a2) and for androgen receptor (AR) revealed that both increased in the hippocampus after exercise, even in ORX rats. All rats were injected twice with 5′-bromo-2′deoxyuridine (50 mg/kg body weight, i.p.) on the day before training. Mild exercise significantly increased AHN in both ORX and Sham rats. Moreover, the increase of doublecortin or 5′-bromo-2′deoxyuridine/NeuN-positive cells in ORX rats was blocked by s.c. flutamide, an AR antagonist. It was also found that application of an estrogen receptor antagonist, tamoxifen, did not suppress exercise-induced AHN. These results support the hypothesis that, in male animals, mild exercise enhances hippocampal synthesis of dihydrotestosterone and increases AHN via androgenenic mediation. PMID:22807478
Characterization of the Binding of a Potent Synthetic Androgen, Methyltrienolone, to Human Tissues
Menon, Mani; Tananis, Catherine E.; Hicks, L. Louise; Hawkins, Edward F.; McLoughlin, Martin G.; Walsh, Patrick C.
1978-01-01
The potent synthetic androgen methytrienolone (R 1881), which does not bind to serum proteins, was utilized to characterize binding to receptors in human androgen responsive tissues. Cytosol extracts prepared from hypertrophic prostates (BPH) were utilized as the source of receptor for the initial studies. High affinity binding was detected in the cytosol of 29 of 30 samples of BPH (average number of binding sites, 45.8±4.7 fmol/mg of protein; dissociation constant, 0.9±0.2 nM). This binding had the characteristics of a receptor: heat lability, precipitability by 0-33% ammonium sulfate and by protamine sulfate, and 8S sedimentation coefficient. High affinity binding was also detected in cytosol prepared from seminal vesicle, epididymis, and genital skin but not in non-genital skin or muscle. However, similar binding was demonstrated in the cytosol of human uterus. The steroid specificities of binding to the cytosol of male tissues of accessory reproduction and of uterus were similar in that progestational agents were more effective competitors than natural androgens. Binding specificities in cytosol prepared from genital skin were distinctly different and were similar to those of ventral prostate from the castrated rat in that dihydrotestosterone was much more potent than progestins in competition. Thus binding of R 1881 to the cytosol of prostate, epididymis, and seminal vesicle has some characteristics of binding to a progesterone receptor. When the nuclear extract from BPH was analyzed, high affinity binding was demonstrated that conformed to the specificities of binding to an androgen receptor. Here dihydrotestosterone was a more potent competitor than progestational agents. Similar patterns of binding were detected in the crude nuclear extracts from seminal vesicle, epididymis, and genital skin but not in uterus, muscle, or non-genital skin. We conclude that the androgen receptor is not demonstrable in the cytosol of prostate, epididymis, or seminal vesicle
Dihydrotestosterone in prostatic hypertrophy
Siiteri, Pentti K.; Wilson, Jean D.
1970-01-01
To explore the relation between androgens and prostatic hypertrophy in man, the concentrations of testosterone, dihydrotestosterone, and androstenedione and the rate of conversion of testosterone to dihydrotestosterone have been measured in normal and hypertrophic prostate tissue. First, a double isotope derivative technique was adapted for the measurement of tissue androgen content in 15 normal and 10 hypertrophic prostates. Although there was no significant difference in the content of androstenedione and testosterone between the two types of tissue, the content of dihydrotestosterone was significantly greater in the hypertrophic tissue (0.60 ±0.10 μg/100 g) than in the normal glands (0.13 ±0.05 μg/100 g). Second, a regional study was performed in three normal prostates and four glands with early hypertrophy, and it was demonstrated that the dihydrotestosterone content was two and three fold greater in the periurethral area where prostatic hypertrophy usually commences than in the outer regions of the gland. Finally, the rate of conversion of testosterone to dihydrotestosterone has been measured under standardized conditions in tissue slices from 4 normal and 20 hypertrophic prostates. There was no significant difference in the rate of dihydrotestosterone formation between the two types of gland (6.0 ±0.8 and 7.8 ±0.5 μμmoles/15 mg of tissue per hr). While the mechanism by which dihydrotestosterone accumulation occurs remains unexplained, it is possible that the local accumulation of dihydrotestosterone may be involved in the pathogenesis of prostatic hypertrophy in man. Images PMID:4194768
Ghatge, Radhika P; Jacobsen, Britta M; Schittone, Stephanie A; Horwitz, Kathryn B
2005-01-01
Introduction Medroxyprogesterone acetate (MPA), the major progestin used for oral contraception and hormone replacement therapy, has been implicated in increased breast cancer risk. Is this risk due to its progestational or androgenic properties? To address this, we assessed the transcriptional effects of MPA as compared with those of progesterone and dihydrotestosterone (DHT) in human breast cancer cells. Method A new progesterone receptor-negative, androgen receptor-positive human breast cancer cell line, designated Y-AR, was engineered and characterized. Transcription assays using a synthetic promoter/reporter construct, as well as endogenous gene expression profiling comparing progesterone, MPA and DHT, were performed in cells either lacking or containing progesterone receptor and/or androgen receptor. Results In progesterone receptor-positive cells, MPA was found to be an effective progestin through both progesterone receptor isoforms in transient transcription assays. Interestingly, DHT signaled through progesterone receptor type B. Expression profiling of endogenous progesterone receptor-regulated genes comparing progesterone and MPA suggested that although MPA may be a somewhat more potent progestin than progesterone, it is qualitatively similar to progesterone. To address effects of MPA through androgen receptor, expression profiling was performed comparing progesterone, MPA and DHT using Y-AR cells. These studies showed extensive gene regulatory overlap between DHT and MPA through androgen receptor and none with progesterone. Interestingly, there was no difference between pharmacological MPA and physiological MPA, suggesting that high-dose therapeutic MPA may be superfluous. Conclusion Our comparison of the gene regulatory profiles of MPA and progesterone suggests that, for physiologic hormone replacement therapy, the actions of MPA do not mimic those of endogenous progesterone alone. Clinically, the complex pharmacology of MPA not only influences its
Androgenic correlates of genetic variation in the gene encoding 5alpha-reductase type 1.
Ellis, Justine A; Panagiotopoulos, Sianna; Akdeniz, Aysel; Jerums, George; Harrap, Stephen B
2005-01-01
Androgens determine male secondary sexual characteristics and influence a variety of metabolic pathways. Circulating levels of androgens are highly heritable; however, the genes involved are largely unknown. The 5alpha-reductase enzymes types 1 and 2 responsible for converting testosterone to the more potent androgen dihydrotestosterone are encoded by the SRD5A1 and SRD5A2 genes, respectively. We performed indirect genetic association studies of SRD5A1 and SRD5A2 and the dihydrotestosterone/testosterone ratio that reflects the activity of 5alpha-reductase in 57 males with type 2 diabetes. We found evidence of significant association between a single nucleotide polymorphism in SRD5A1 and the dihydrotestosterone/testosterone ratio (median 0.10, interquartile range 0.08 vs. median 0.06, interquartile range 0.04, P = 0.009). The polymorphism was not associated with any diabetic phenotypes. These results suggest that functional genetic variants might exist in or around SRD5A1 that affect the activity of the 5alpha-reductase enzyme type 1 and influence androgen levels.
Giorgi, Eleonora P.; Shirley, I. M.; Grant, J. K.; Stewart, Joan C.
1973-01-01
Hyperplastic and adenocarcinomatous human prostatic tissue was superfused in vitro with radioactively labelled androst-4-ene-3,17-dione, testosterone and 5α-dihydrotestosterone (17β-hydroxy-5α-androstan-3-one), with and without addition of the anti-androgens cyproterone and cyproterone acetate. Cyproterone competitively inhibited the entry of the androgens into the majority of the tissues, whereas cyproterone acetate increased this entry. These findings indicated that transport of androstenedione, testosterone and 5α-dihydrotestosterone into prostatic tissue is performed by a specific mechanism, possibly involving a carrier situated in the cell membrane. The extent of metabolism of the three androgens was also modified: formation of 5α-dihydrotestosterone from testosterone, and of the latter from androstenedione, was decreased by cyproterone and increased by the acetate. Acetate was more effective than cyproterone in decreasing the `uptake' of the perfused androgens by the tissue; at the same time, it increased the androgen clearance from the tissue. As cyproterone acetate is the more potent of the two anti-androgens, the possibility that these findings in vitro are related to the different anti-androgenic potency exhibited by the two compounds in vivo is discussed. `Uptake' of the two anti-androgens and the response to their action on androgen dynamics were similar in adenocarcinomatous and hyperplastic glands. PMID:4125095
Becker, David; Wain, Lisa M; Chong, Yih Harng; Gosai, Sonal J; Henderson, Nina K; Milburn, Jacqui; Stott, Victoria; Wheeler, Benjamin J
2016-02-01
X-linked partial androgen insensitivity syndrome (PAIS) causes under-virilization at all stages of development. In two thirds of males, this results in micropenis. Dihydrotestosterone (DHT) is a potent androgen that is critical for male genital development, which when applied topically, has been shown to increase penile length with micropenis of varying etiologies. We present the first case series using topical DHT gel to treat micropenis in 46,XY males with PAIS, before, during, and after puberty. Three related 46,XY males with confirmed p.L712F androgen receptor mutations exhibited varying degrees of micropenis post-surgical correction. They were of pre-pubertal, peri-pubertal and adult ages, respectively. Following baseline clinical and laboratory assessments all completed a 4-month course of daily DHT gel 2.5% (androstanolone) topically to penis (0.3 mg/kg body weight), with monitoring for adverse effects. Primary outcome was change in stretched penile length (SPL) following treatment. Mixed results were obtained following topical DHT therapy. In the pre- and peri- pubertal patients, SPL changed from 2.5 cm to 3.5 cm (+40%), and 3.5 cm to 5.7 cm (+63%), respectively. In the adult patient with 1 year of prior high-dose weekly testosterone therapy, no additional change in SPL was seen. No adverse effects of topical DHT were reported or observed throughout the 4 months of treatment. Topical DHT treatment appears to be a safe and well-tolerated method of virilising micropenis both prior to and during puberty in children with PAIS. Questions remain about long-term outcomes into adulthood, and efficacy in adults with prior lengthy exposure to high-dose testosterone.
Androgen resistance in squirrel monkeys (Saimiri spp.).
Gross, Katherine L; Westberry, Jenne M; Hubler, Tina R; Sadosky, Patti W; Singh, Ravinder J; Taylor, Robert L; Scammell, Jonathan G
2008-08-01
The goal of this study was to understand the basis for high androgen levels in squirrel monkeys (Saimiri spp.). Mass spectrometry was used to analyze serum testosterone, androstenedione, and dihydrotestosterone of male squirrel monkeys during the nonbreeding (n = 7) and breeding (n = 10) seasons. All hormone levels were elevated compared with those of humans, even during the nonbreeding season; the highest levels occurred during the breeding season. The ratio of testosterone to dihydrotestosterone in squirrel monkeys is high during the breeding season compared to man. Squirrel monkeys may have high testosterone to compensate for inefficient metabolism to dihydrotestosterone. We also investigated whether squirrel monkeys have high androgens to compensate for low-activity androgen receptors (AR). The response to dihydrotestosterone in squirrel monkey cells transfected with AR and AR-responsive reporter plasmids was 4-fold, compared with 28-fold in human cells. This result was not due to overexpression of cellular FKBP51, which causes glucocorticoid and progestin resistance in squirrel monkeys, because overexpression of FKBP51 had no effect on dihydrotestosterone-stimulated reporter activity in a human fibroblast cell line. To test whether the inherently low levels of FKBP52 in squirrel monkeys contribute to androgen insensitivity, squirrel monkey cells were transfected with an AR expression plasmid, an AR-responsive reporter plasmid, and a plasmid expressing FKBP52. Expression of FKBP52 decreased the EC50 or increased the maximal response to dihydrotestosterone. Therefore, the high androgen levels in squirrel monkeys likely compensate for their relatively low 5 alpha-reductase activity during the breeding season and AR insensitivity resulting from low cellular levels of FKBP52.
Montaño, Luis M; Espinoza, Julia; Flores-Soto, Edgar; Chávez, Jaime; Perusquía, Mercedes
2014-07-01
Changes in the androgen levels in asthmatic men may be associated with the severity of asthma. Androgens induce a nongenomic relaxation in airway smooth muscle, but the underlying mechanisms remain unclear. The aim of this study was to investigate the potential bronchorelaxing action of testosterone (TES) and its metabolites (5α- and 5β-dihydrotestosterone (DHT). A preventive effect on ovalbumin (OVA)-induced bronchospasm was observed in sensitized guinea pigs for each androgen. Androgens were studied in response to bronchoconstrictors: carbachol (CCh) and KCl in isolated trachea rings with and without epithelium from non-sensitized and sensitized animals as well as on OVA-induced contraction. Androgens concentration-dependently abolished the contraction in response to CCh, KCl, and OVA. There were significant differences in the sensitivity to the relaxation induced by each androgen. 5β-DHT was more potent for relaxing KCl-induced contraction, while TES and 5α-DHT were more potent for CCh- and OVA-induced contraction. No differences were found in preparations with and without epithelium or in the presence of a nitric oxide (NO) synthase inhibitor or an inhibitor of K(+) channels. These data indicate the absence of involvement of the epithelium-, NO- and K(+) channels-dependent pathway in androgen-induced relaxation. However, in dissociated tracheal myocytes loaded with the calcium-binding fluorescent dye Fura -2, physiological concentrations of androgens decreased the KCl-induced [Ca(2+)]i increment. 5β-DHT was the most potent at decreasing KCl-induced [Ca(2+)]i increment and preventing bronchospasm. We suggest that androgen-induced brochorelaxation was mediated via decreased Ca(2+) influx through L-type Ca(2+)channels but additional Ca(2+) entry blockade may be involved. Molecular changes in androgen structure may determine its preferential site of action. © 2014 Society for Endocrinology.
Perusquía, Mercedes
2010-01-01
The marked sexual dimorphism that exists in human cardiovascular diseases has led to the dogmatic concept that testosterone (Tes) has deleterious effects and exacerbates the development of cardiovascular disease in males. While some animal studies suggest that Tes does exert deleterious effects by enhancing vascular tone through acute or chronic mechanisms, accumulating evidence suggests that Tes and other androgens exert beneficial effects by inducing rapid vasorelaxation of vascular smooth muscle through nongenomic mechanisms. While this effect frequently has been observed in large arteries at micromolar concentrations, more recent studies have reported vasorelaxation of smaller resistance arteries at nanomolar (physiological) concentrations. The key mechanism underlying Tes-induced vasorelaxation appears to be the modulation of vascular smooth muscle ion channel function, particularly the inactivation of L-type voltage-operated Ca2+ channels and/or the activation of voltage-operated and Ca2+-activated K+ channels. Studies employing Tes analogs and metabolites reveal that androgen-induced vasodilation is a structurally specific nongenomic effect that is fundamentally different than the genomic effects on reproductive targets. For example, 5α-dihydrotestosterone exhibits potent genomic-androgenic effects but only moderate vasorelaxing activity, whereas its isomer 5β-dihydrotestosterone is devoid of androgenic effects but is a highly efficacious vasodilator. These findings suggest that the dihydro-metabolites of Tes or other androgen analogs devoid of androgenic or estrogenic effects could have useful therapeutic roles in hypertension, erectile dysfunction, prostatic ischemia, or other vascular dysfunctions. PMID:20228257
Selective androgen receptor modulators: in pursuit of tissue-selective androgens.
Omwancha, Josephat; Brown, Terry R
2006-10-01
The androgen receptor mediates the androgenic and anabolic activity of the endogenous steroids testosterone and 5alpha-dihydrotestosterone. Current knowledge of the androgen receptor protein structure, and the molecular mechanisms surrounding the binding properties and activities of agonists and antagonists has led to the design and development of novel nonsteroidal ligands with selected tissue-specific androgen receptor agonist and antagonist activities. The activity of these compounds, termed selective androgen receptor modulators (SARMs), is directed toward the maintenance or enhancement of anabolic effects on bone and muscle with minimal androgenic effects on prostate growth. SARMs are of potential therapeutic value in the treatment of male hypogonadism, osteoporosis, frailty and muscle wasting, burn injury and would healing, anemia, mood and depression, benign prostatic hyperplasia and prostate cancer.
Perez-Pouchoulen, Miguel; Roby, Clinton R.; Ryan, Timothy E.; McCarthy, Margaret M.
2014-01-01
Sex differences in vocal communication are prevalent in both the animals and humans. The mechanism(s) mediating gender differences in human language are unknown, although, sex hormones, principally androgens, play a central role in the development of vocalizations in a wide variety of animal species. The discovery of FOXP2 has added an additional avenue for exploring the origins of language and animal communication. The FOXP2 gene is a member of the forkhead box P (FOXP) family of transcription factors. Prior to the prenatal androgen surge in male fetuses, we observed no sex difference for Foxp2 protein levels in cultured cells. In contrast, 24 hours after the onset of the androgen surge, we found a sex difference for Foxp2 protein levels in cultured cortical cells with males having higher levels than females. Furthermore, we observed the potent nonaromatizable androgen dihydrotestosterone altered not only Foxp2 mRNA and protein levels but also Foxp1. Androgen effects on both Foxp2 and Foxp1 were found to occur in the striatum, cerebellar vermis, and cortex. Immunofluorescence microscopy and coimmunoprecipitation demonstrate Foxp2 and the androgen receptor protein interact. Databases for transcription factor binding sites predict a consensus binding motif for androgen receptor on the Foxp2 promoter regions. We also observed a sex difference in rat pup vocalization with males vocalizing more than females and treatment of females with dihydrotestosterone eliminated the sex difference. We propose that androgens might be an upstream regulator of both Foxp2 and Foxp1 expression and signaling. This has important implications for language and communication as well as neuropsychiatric developmental disorders involving impairments in communication. PMID:25247470
Bowers, J Michael; Perez-Pouchoulen, Miguel; Roby, Clinton R; Ryan, Timothy E; McCarthy, Margaret M
2014-12-01
Sex differences in vocal communication are prevalent in both the animals and humans. The mechanism(s) mediating gender differences in human language are unknown, although, sex hormones, principally androgens, play a central role in the development of vocalizations in a wide variety of animal species. The discovery of FOXP2 has added an additional avenue for exploring the origins of language and animal communication. The FOXP2 gene is a member of the forkhead box P (FOXP) family of transcription factors. Prior to the prenatal androgen surge in male fetuses, we observed no sex difference for Foxp2 protein levels in cultured cells. In contrast, 24 hours after the onset of the androgen surge, we found a sex difference for Foxp2 protein levels in cultured cortical cells with males having higher levels than females. Furthermore, we observed the potent nonaromatizable androgen dihydrotestosterone altered not only Foxp2 mRNA and protein levels but also Foxp1. Androgen effects on both Foxp2 and Foxp1 were found to occur in the striatum, cerebellar vermis, and cortex. Immunofluorescence microscopy and coimmunoprecipitation demonstrate Foxp2 and the androgen receptor protein interact. Databases for transcription factor binding sites predict a consensus binding motif for androgen receptor on the Foxp2 promoter regions. We also observed a sex difference in rat pup vocalization with males vocalizing more than females and treatment of females with dihydrotestosterone eliminated the sex difference. We propose that androgens might be an upstream regulator of both Foxp2 and Foxp1 expression and signaling. This has important implications for language and communication as well as neuropsychiatric developmental disorders involving impairments in communication.
An Update on Plant Derived Anti-Androgens
Grant, Paul; Ramasamy, Shamin
2012-01-01
Anti-androgens are an assorted group of drugs and compounds that reduce the levels or activity of androgen hormones within the human body. Disease states in which this is relevant include polycystic ovarian syndrome, hirsutism, acne, benign prostatic hyperplasia, and endocrine related cancers such as carcinoma of the prostate. We provide an overview and discussion of the use of anti-androgen medications in clinical practice and explore the increasing recognition of the benefits of plant-derived anti-androgens, for example, spearmint tea in the management of PCOS, for which some evidence about efficacy is beginning to emerge. Other agents covered include red reishi, which has been shown to reduce levels 5-alpha reductase, the enzyme that facilitates conversion of testosterone to dihydrotestosterone (DHT); licorice, which has phytoestrogen effects and reduces testosterone levels; Chinese peony, which promotes the aromatization of testosterone into estrogen; green tea, which contains epigallocatechins and also inhibits 5-alpha reductase, thereby reducing the conversion of normal testosterone into the more potent DHT; black cohosh, which has been shown to kill both androgenresponsive and non-responsive human prostate cancer cells; chaste tree, which has a reduces prolactin from the anterior pituitary; and saw palmetto extract, which is used as an anti-androgen although it shown no difference in comparison to placebo in clinical trials. PMID:23843810
Dihydrotestosterone synthesis bypasses testosterone to drive castration-resistant prostate cancer
Chang, Kai-Hsiung; Li, Rui; Papari-Zareei, Mahboubeh; Watumull, Lori; Zhao, Yan Daniel; Auchus, Richard J.; Sharifi, Nima
2011-01-01
In the majority of cases, advanced prostate cancer responds initially to androgen deprivation therapy by depletion of gonadal testosterone. The response is usually transient, and metastatic tumors almost invariably eventually progress as castration-resistant prostate cancer (CRPC). The development of CRPC is dependent upon the intratumoral generation of the potent androgen, dihydrotestosterone (DHT), from adrenal precursor steroids. Progression to CRPC is accompanied by increased expression of steroid-5α-reductase isoenzyme-1 (SRD5A1) over SRD5A2, which is otherwise the dominant isoenzyme expressed in the prostate. DHT synthesis in CRPC is widely assumed to require 5α-reduction of testosterone as the obligate precursor, and the increased expression of SRD5A1 is thought to reflect its role in converting testosterone to DHT. Here, we show that the dominant route of DHT synthesis in CRPC bypasses testosterone, and instead requires 5α-reduction of androstenedione by SRD5A1 to 5α-androstanedione, which is then converted to DHT. This alternative pathway is operational and dominant in both human CRPC cell lines and fresh tissue obtained from human tumor metastases. Moreover, CRPC growth in mouse xenograft models is dependent upon this pathway, as well as expression of SRD5A1. These findings reframe the fundamental metabolic pathway that drives CRPC progression, and shed light on the development of new therapeutic strategies. PMID:21795608
Dihydrotestosterone synthesis bypasses testosterone to drive castration-resistant prostate cancer.
Chang, Kai-Hsiung; Li, Rui; Papari-Zareei, Mahboubeh; Watumull, Lori; Zhao, Yan Daniel; Auchus, Richard J; Sharifi, Nima
2011-08-16
In the majority of cases, advanced prostate cancer responds initially to androgen deprivation therapy by depletion of gonadal testosterone. The response is usually transient, and metastatic tumors almost invariably eventually progress as castration-resistant prostate cancer (CRPC). The development of CRPC is dependent upon the intratumoral generation of the potent androgen, dihydrotestosterone (DHT), from adrenal precursor steroids. Progression to CRPC is accompanied by increased expression of steroid-5α-reductase isoenzyme-1 (SRD5A1) over SRD5A2, which is otherwise the dominant isoenzyme expressed in the prostate. DHT synthesis in CRPC is widely assumed to require 5α-reduction of testosterone as the obligate precursor, and the increased expression of SRD5A1 is thought to reflect its role in converting testosterone to DHT. Here, we show that the dominant route of DHT synthesis in CRPC bypasses testosterone, and instead requires 5α-reduction of androstenedione by SRD5A1 to 5α-androstanedione, which is then converted to DHT. This alternative pathway is operational and dominant in both human CRPC cell lines and fresh tissue obtained from human tumor metastases. Moreover, CRPC growth in mouse xenograft models is dependent upon this pathway, as well as expression of SRD5A1. These findings reframe the fundamental metabolic pathway that drives CRPC progression, and shed light on the development of new therapeutic strategies.
Qin, Li; Pei, Cheng; Kang, Qian-Yan; Liu, Zhao; Li, Li
2016-01-01
To explore the effects of the androgen dihydrotestosterone on the expression of mucin 1 (MUC1) and the activity of Wnt signaling in mouse corneal epithelial cells. Primary mouse corneal epithelial cells were isolated from the corneas of BALB/c mice. Quantitative real-time polymerase chain reaction, immunofluorescence and Western blot analysis were used to quantify the differential expression of selected genes. The androgen receptor was silenced by transfecting cells with androgen receptor shRNAs. TOP-Flash and FOP-flash reporter plasmids were used to measure β-catenin-driven transcription. Dihydrotestosterone treatment increased MUC1 expression and activated the Wnt signaling pathway and led to the translocation of β-catenin and upregulation of the Wnt downstream target gene TATA box binding protein and urokinase plasminogen activator. These effects were prevented by downregulating the androgen receptor. Androgens may protect against dry eye by regulating the expression of MUC1 which is stimulated by the activation of Wnt signaling via the androgen receptor. An understanding of the mechanisms associated with androgen-mediated protection against dry eye is an important step in developing new therapies for this disease.
Chinta, Gopichand; Ramya Chandar Charles, Mariasoosai; Klopčič, Ivana; Sollner Dolenc, Marija; Periyasamy, Latha; Selvaraj Coumar, Mohane
2015-07-01
Understanding the molecular mechanism of action of traditional medicines is an important step towards developing marketable drugs from them. Piperine, an active constituent present in the Piper species, is used extensively in Ayurvedic medicines (practiced on the Indian subcontinent). Among others, piperine is known to possess a male contraceptive effect; however, the molecular mechanism of action for this effect is not very clear. In this regard, detailed docking and molecular dynamics simulation studies of piperine with the androgen-binding protein and androgen receptors were carried out. Androgen receptors control male sexual behavior and fertility, while the androgen-binding protein binds testosterone and maintains its concentration at optimal levels to stimulate spermatogenesis in the testis. It was found that piperine docks to the androgen-binding protein, similar to dihydrotestosterone, and to androgen receptors, similar to cyproterone acetate (antagonist). Also, the piperine-androgen-binding protein and piperine-androgen receptors interactions were found to be stable throughout 30 ns of molecular dynamics simulation. Further, two independent simulations for 10 ns each also confirmed the stability of these interactions. Detailed analysis of the piperine-androgen-binding protein interactions shows that piperine interacts with Ser42 of the androgen-binding protein and could block the binding with its natural ligands dihydrotestosterone/testosterone. Moreover, piperine interacts with Thr577 of the androgen receptors in a manner similar to the antagonist cyproterone acetate. Based on the in silico results, piperine was tested in the MDA-kb2 cell line using the luciferase reporter gene assay and was found to antagonize the effect of dihydrotestosterone at nanomolar concentrations. Further detailed biochemical experiments could help to develop piperine as an effective male contraceptive agent in the future. Georg Thieme Verlag KG Stuttgart · New York.
Karolczak, Kamil; Konieczna, Lucyna; Kostka, Tomasz; Witas, Piotr J; Soltysik, Bartlomiej; Baczek, Tomasz; Watala, Cezary
2018-05-02
The cardiovascular effects of testosterone and dihydrotestosterone are generally attributed to their modulatory action on lipid and glucose metabolism. However, no ex vivo studies suggest that circulating androgen levels influence the activation and reactivity of blood platelets - one of the main components of the haemostasis system directly involved in atherosclerosis. The levels of testosterone, dihydrotestosterone and oestradiol in plasma from men and women aged from 60 to 65 years were measured by LC-MS; the aim was to identify any potential relationships between sex steroid levels and the markers of platelet activation (surface membrane expression of GPII/IIIa complex and P-selectin) and platelet reactivity in response to arachidonate, collagen or ADP, monitored with whole blood aggregometry and flow cytometry. The results of the ex vivo part of the study indicate that the concentrations of testosterone and its reduced form, dihydrotestosterone are significantly negatively associated with platelet activation and reactivity. These observations were confirmed in an in vitro model: testosterone and dihydrotestosterone significantly inhibited platelet aggregation triggered by arachidonate or collagen. Our findings indicate that testosterone and dihydrotestosterone are significant haemostatic steroids with inhibitory action on blood platelets in older people.
Handa, Robert J.; Pak, Toni R.; Kudwa, Andrea E.; Lund, Trent D.; Hinds, Laura
2008-01-01
The complexity of gonadal steroid hormone actions is reflected in their broad and diverse effects on a host of integrated systems including reproductive physiology, sexual behavior, stress responses, immune function, cognition, and neural protection. Understanding the specific contributions of androgens and estrogens in neurons that mediate these important biological processes is central to the study of neuroendocrinology. Of particular interest in recent years has been the biological role of androgen metabolites. The goal of this review is to highlight recent data delineating the specific brain targets for the dihydrotestosterone metabolite, 5α-androstane, 3β, 17β-diol (3β-Diol). Studies using both in vitro and in vivo approaches provide compelling evidence that 3β-Diol is an important modulator of the stress response mediated by the hypothalmo-pituitary-adrenal axis. Further, the actions of 3β-Diol are mediated by estrogen receptors, and not androgen receptors, often through a canonical estrogen response element in the promoter of a given target gene. These novel findings compel us to re-evaluate the interpretation of past studies and the design of future experiments aimed at elucidating the specific effects of androgen receptor signaling pathways. PMID:18067894
Lundqvist, Johan; Tringali, Corrado; Oskarsson, Agneta
2017-11-01
Prostate cancer growth and progression are mainly dependent on androgens and many current prostate cancer treatment options target the synthesis or function of androgens. We have previously reported that resveratrol and synthetic analogs of resveratrol with a higher bioavailability inhibit the synthesis of androgens in human adrenocortical H295R cells. Now we have studied the antiandrogenic properties of resveratrol, piceatannol and analogs in two different prostate cell lines; LNCaP and RWPE. LNCaP carry a T877A mutation in the androgen receptor while RWPE has a wild-type androgen receptor. We found that resveratrol, piceatannol and all studied analogs were able to inhibit a dihydrotestosterone-induced activation of the androgen receptor, showing that they act as antiandrogens. In LNCaP cells, all studied compounds were able to statistically significantly decrease the androgenic signaling in concentrations ≥1μM and the synthetic analogs trimethylresveratrol (RSVTM) and tetramethylpiceatannol (PICTM) were the most potent compounds. RWPE cells were not as responsive to the studied compounds as the LNCaP cells. A statistically significant decrease in the androgenic signaling was observed at concentrations ≤5μM for most compounds and RSVTM was found to be the most potent compound. Further, we studied the effects of resveratrol, piceatannol and analogs on the levels of prostate-specific antigen (PSA) in LNCaP cells and found that all studied compounds decreased the level of PSA and that the synthetic analogs diacetylresveratrol (RSVDA), triacetylresveratrol (RSVTA) and RSVTM were the most potent compounds, decreasing the PSA level by approx. 50% at concentrations ≥10μM. In a cell-free receptor binding assay we were unable to show binding of resveratrol or analogs to the ligand binding domain of the androgen receptor, indicating that the observed effects are mediated via other mechanisms than direct ligand competition. We conclude that the resveratrol
Kaur, Satwant; Baynes, Alice; Lockyer, Anne E; Routledge, Edwin J; Jones, Catherine S; Noble, Leslie R; Jobling, Susan
2016-01-01
Gastropod mollusks have been proposed as alternative models for male reproductive toxicity testing, due to similarities in their reproductive anatomy compared to mammals, together with evidence that endocrine disrupting chemicals can cause effects in some mollusks analogous to those seen in mammals. To test this hypothesis, we used the freshwater pulmonate snail, Biomphalaria glabrata, for which various genetic tools and a draft genome have recently become available, to investigate the effects of two steroid androgens on the development of mollusk secondary sexual organs. Here we present the results of exposures to two potent androgens, the vertebrate steroid; 5α-dihydrotestosterone (DHT) and the pharmaceutical anabolic steroid; 17α-methyltestosterone (MT), under continuous flow-through conditions throughout embryonic development and up to sexual maturity. Secondary sexual gland morphology, histopathology and differential gene expression analysis were used to determine whether steroid androgens stimulated or inhibited organ development. No significant differences between tissues from control and exposed snails were identified, suggesting that these androgens elicited no biologically detectable response normally associated with exposure to androgens in vertebrate model systems. Identifying no effect of androgens in this mollusk is significant, not only in the context of the suitability of mollusks as alternative model organisms for testing vertebrate androgen receptor agonists but also, if applicable to other similar mollusks, in terms of the likely impacts of androgens and anti-androgenic pollutants present in the aquatic environment.
Komori, S; Sakata, K; Kasumi, H; Tsuji, Y; Hamada, K; Koyama, K
1999-10-01
DNA analysis of the androgen receptor gene in a patient with complete androgen insensitivity syndrome identified a substitutional mutation (tyrosine converted to cysteine at position 571) in the DNA binding domain. In vitro transfection experiments with the patients' androgen receptor gene, indicated normal expression of the androgen receptor in transfected COS-7 cells compared to the wild type gene. There was also no evidence of impaired thermal stability of the 5 alpha-dihydrotestosterone-androgen receptor complex. However, the capacity of the androgen receptor to activate target gene transcription was found to be completely disrupted in a luciferase assay. These results confirmed that only one substitutional mutation in the DNA binding domain was related to the pathogenesis of the complete androgen insensitivity syndrome.
Miljkovic, Iva; Cauley, Jane A; Dressen, Amy S; Gordon, Christopher L; Goodpaster, Bret H; Kuller, Lewis H; Bunker, Clareann H; Patrick, Alan L; Wheeler, Victor W; Orwoll, Eric S; Zmuda, Joseph M
2011-01-01
Aging is associated with declining serum levels of androgenic hormones and with increased skeletal muscle fat infiltration, an emerging risk factor for type 2 diabetes mellitus (T2DM). Androgens regulate fat mass and glucose homeostasis, but the effect of androgenic hormones on skeletal muscle fat infiltration is largely unknown. Thus, the aim of the current study was to examine the association of serum androgens and their precursors and metabolites with skeletal muscle fat infiltration and T2DM in a black male population group at high risk of T2DM. Serum androgens, estrogens, and androgen precursors and metabolites were measured using mass spectrometry, and calf skeletal muscle fat distribution [subcutaneous and intermuscular fat; skeletal muscle density] were measured using quantitative computed tomography in 472 Afro-Caribbean men aged 65 and older. Bioactive androgens, testosterone, free testosterone and dihydrotestosterone, were associated with less skeletal muscle fat infiltration (r=−0.14 to −0.18, P<0.05) and increased skeletal muscle density (r=0.10 to 0.14, P<0.05), independent of total adiposity. Additionally, glucuronidated androgen metabolites were associated with less subcutaneous fat (r=−0.11 to −0.15, P<0.05). Multivariate logistic regression analysis identified an increased level of 3α-diol-3 glucuronide (OR=1.38, P<0.01) and a decreased level of dihydrotestosterone (OR=0.66, P<0.01) to be significantly associated with T2DM. Our findings suggest that in elderly black men, independent of total adiposity, bioactive androgens and glucuronidated androgen metabolites may play previously unrecognized role in skeletal muscle fat distribution. Longitudinal studies are needed to further evaluate the relationship between androgens and androgen metabolites with changes in skeletal muscle fat distribution with aging and the incidence of T2DM. PMID:21353258
Mohler, James L; Titus, Mark A; Wilson, Elizabeth M
2011-09-15
High-affinity binding of dihydrotestosterone (DHT) to the androgen receptor (AR) initiates androgen-dependent gene activation, required for normal male sex development in utero, and contributes to prostate cancer development and progression in men. Under normal physiologic conditions, DHT is synthesized predominantly by 5α-reduction of testosterone, the major circulating androgen produced by the testis. During androgen deprivation therapy, intratumoral androgen production is sufficient for AR activation and prostate cancer growth, even though circulating testicular androgen levels are low. Recent studies indicate that the metabolism of 5α-androstane-3α, 17β-diol by 17β-hydroxysteroid dehydrogenase 6 in benign prostate and prostate cancer cells is a major biosynthetic pathway for intratumoral synthesis of DHT, which binds AR and initiates transactivation to promote prostate cancer growth during androgen deprivation therapy. Drugs that target the so-called backdoor pathway of DHT synthesis provide an opportunity to enhance clinical response to luteinizing-hormone-releasing hormone (LHRH) agonists or antagonists, AR antagonists, and inhibitors of 5α-reductase enzymes (finasteride or dutasteride), and other steroid metabolism enzyme inhibitors (ketoconazole or the recently available abiraterone acetate). ©2011 AACR.
Kwack, Mi Hee; Ahn, Ji Sup; Kim, Moon Kyu; Kim, Jung Chul; Sung, Young Kwan
2010-10-01
In a previous study, we recently claimed that dihydrotestosterone (DHT)-inducible dickkopf-1 (DKK-1) expression is one of the key factors involved in androgen-potentiated balding. We also demonstrated that L-ascorbic acid 2-phosphate (Asc 2-P) represses DHT-induced DKK-1 expression in cultured dermal papilla cells (DPCs). Here, we investigated whether or not L-threonate could attenuate DHT-induced DKK-1 expression. We observed via RT-PCR analysis and enzyme-linked immunosorbent assay that DHT-induced DKK-1 expression was attenuated in the presence of L-threonate. We also found that DHT-induced activation of DKK-1 promoter activity was significantly repressed by L-threonate. Moreover, a co-culture system featuring outer root sheath (ORS) keratinocytes and DPCs showed that DHT inhibited the growth of ORS cells, which was then significantly reversed by L-threonate. Collectively, these results indicate that L-threonate inhibited DKK-1 expression in DPCs and therefore is a good treatment for the prevention of androgen-driven balding.
Lockyer, Anne E.; Routledge, Edwin J.; Jones, Catherine S.; Noble, Leslie R.; Jobling, Susan
2016-01-01
Gastropod mollusks have been proposed as alternative models for male reproductive toxicity testing, due to similarities in their reproductive anatomy compared to mammals, together with evidence that endocrine disrupting chemicals can cause effects in some mollusks analogous to those seen in mammals. To test this hypothesis, we used the freshwater pulmonate snail, Biomphalaria glabrata, for which various genetic tools and a draft genome have recently become available, to investigate the effects of two steroid androgens on the development of mollusk secondary sexual organs. Here we present the results of exposures to two potent androgens, the vertebrate steroid; 5α-dihydrotestosterone (DHT) and the pharmaceutical anabolic steroid; 17α-methyltestosterone (MT), under continuous flow-through conditions throughout embryonic development and up to sexual maturity. Secondary sexual gland morphology, histopathology and differential gene expression analysis were used to determine whether steroid androgens stimulated or inhibited organ development. No significant differences between tissues from control and exposed snails were identified, suggesting that these androgens elicited no biologically detectable response normally associated with exposure to androgens in vertebrate model systems. Identifying no effect of androgens in this mollusk is significant, not only in the context of the suitability of mollusks as alternative model organisms for testing vertebrate androgen receptor agonists but also, if applicable to other similar mollusks, in terms of the likely impacts of androgens and anti-androgenic pollutants present in the aquatic environment. PMID:27448327
Rutherford, Robert; Lister, Andrea; Hewitt, L Mark; MacLatchy, Deborah
2015-04-01
Androgens originating from pulp mill processing, sewage treatment facilities and agricultural activities have the potential for discharge into aquatic receiving environments. To assess androgen effects on reproductive endocrine status in fish in estuarine environments, male and female adult northern mummichog (Fundulus heteroclitus macrolepidotus) were exposed to an aromatizable androgen (17α-methyltestosterone; MT) and a non-aromatizable androgen (5α-dihydrotestosterone; DHT) in a short-term reproductive endocrine bioassay. Fish were nominally exposed to 10 μg/L or 100 μg/L DHT, or 0.1 μg/L or 1 μg/L MT for 14 days during gonadal recrudescence. Actual concentrations of androgens, as measured by enzyme immunoassay (EIA), were 10-49% of nominal MT 0.1, 3-6% of nominal MT 1, 5-10% of nominal DHT 10 and 3-25% of nominal DHT 100. Female mummichog were impacted to a greater degree by androgen exposure, with increased plasma testosterone (T) at 100 μg/L DHT, depressed plasma 17β-estradiol (E2) at both DHT concentrations and at 1 μg/L MT, as well as depressed in vitro E2 at both MT concentrations and 100 μg/L DHT. Males had depressed plasma T in the 10 μg/L DHT treatment and depressed in vitro 11-ketotestosterone production for both MT concentrations and 10 μg/L DHT. Ovarian aromatase gene expression was induced in females exposed to 1 μg/L MT. DHT at 100 μg/L increased hepatic vitellogenin-1 (VTG1) expression in males and depressed VTG1 expression in females. The range of responses between sexes and among species provides evidence for modes of actions and potential impacts of androgens in aquatic receiving environments. Copyright © 2015 Elsevier Inc. All rights reserved.
Urysiak-Czubatka, Izabela; Broniarczyk-Dyła, Grażyna
2014-01-01
Introduction Androgenetic alopecia (AGA) is the most common form of hair loss. Clinically observed hair loss is due to the continuous miniaturization of affected hair follicles. Genetic factors and androgenic factors especially dihydrotestosterone (DHT), which is a testosterone tissue metabolite, play major roles in the pathogenesis of AGA. However, expert opinions about the usefulness of DHT in the diagnosis of this type of alopecia are divided. Aim To evaluate the usefulness of DHT level in patients with androgenetic alopecia compared with the control group. Material and methods The study comprised 49 subjects: 19 women and 9 men with androgenetic alopecia. The control group consisted of 17 healthy women and 4 men without hair loss. Results Increased serum concentrations of DHT were observed in patients with androgenetic alopecia (17 women, 5 men), but also in the control group. The differences in mean values of DHT were not significant according to the types of alopecia and the control group. Increased serum concentrations of DHT were not correlated with the advance of alopecia. Conclusions Dihydrotestosterone is the most influential androgen and seems to play a very important role in the pathogenesis of androgenetic alopecia. Based on the results of our study and others, the most important factors would appear to be the genetically-determined sensitivity of the follicles to DHT and their different reactions to androgen concentration. PMID:25254005
Wu, Yue; Godoy, Alejandro; Azzouni, Faris; Wilton, John H; Ip, Clement; Mohler, James L
2013-09-01
Blocking 5α-reductase-mediated testosterone conversion to dihydrotestosterone (DHT) with finasteride or dutasteride is the driving hypothesis behind two prostate cancer prevention trials. Factors affecting intracellular androgen levels and the androgen receptor (AR) signaling axis need to be examined systematically in order to fully understand the outcome of interventions using these drugs. The expression of three 5α-reductase isozymes, as determined by immunohistochemistry and qRT-PCR, was studied in five human prostate cancer cell lines. Intracellular testosterone and DHT were analyzed using mass spectrometry. A luciferase reporter assay and AR-regulated genes were used to evaluate the modulation of AR activity. Prostate cancer cells were capable of accumulating testosterone to a level 15-50 times higher than that in the medium. The profile and expression of 5α-reductase isozymes did not predict the capacity to convert testosterone to DHT. Finasteride and dutasteride were able to depress testosterone uptake in addition to lowering intracellular DHT. The inhibition of AR activity following drug treatment often exceeded the expected response due to reduced availability of DHT. The ability to maintain high intracellular testosterone might compensate for the shortage of DHT. The biological effect of finasteride or dutasteride appears to be complex and may depend on the interplay of several factors, which include testosterone turnover, enzymology of DHT production, ability to use testosterone and DHT interchangeably, and propensity of cells for off-target AR inhibitory effect. © 2013 Wiley Periodicals, Inc.
Enzalutamide inhibits androgen receptor-positive bladder cancer cell growth.
Kawahara, Takashi; Ide, Hiroki; Kashiwagi, Eiji; El-Shishtawy, Kareem A; Li, Yi; Reis, Leonardo O; Zheng, Yichun; Miyamoto, Hiroshi
2016-10-01
Emerging preclinical evidence suggests that androgen-mediated androgen receptor (AR) signals promote bladder cancer progression. However, little is known about the efficacy of an AR signaling inhibitor, enzalutamide, in the growth of bladder cancer cells. In this study, we compared the effects of enzalutamide and 2 other classic antiandrogens, flutamide and bicalutamide, on androgen-induced bladder cancer cell proliferation, migration, and invasion as well as tumor growth in vivo. Thiazolyl blue cell viability assay, flow cytometry, scratch wound-healing assay, transwell invasion assay, real-time polymerase chain reaction, and reporter gene assay were performed in AR-positive (e.g., UMUC3, TCCSUP, and 647V-AR) and AR-negative (e.g., UMUC3-AR-short hairpin RNA [shRNA], TCCSUP-AR-shRNA, 647V) bladder cancer lines treated with dihydrotestosterone and each AR antagonist. We also used a mouse xenograft model for bladder cancer. Dihydrotestosterone increased bladder cancer cell proliferation, migration, and invasion indicating that endogenous or exogenous AR was functional. Enzalutamide, hydroxyflutamide, and bicalutamide showed similar inhibitory effects, without significant agonist activity, on androgen-mediated cell viability/apoptosis, cell migration, and cell invasion in AR-positive lines. No significant effects of dihydrotestosterone as well as AR antagonists on the growth of AR-negative cells were seen. Correspondingly, in UMUC3 cells, these AR antagonists down-regulated androgen-induced expression of AR, matrix metalloproteinase-2, and interleukin-6. Androgen-enhanced AR-mediated transcriptional activity was also blocked by each AR antagonist exhibiting insignificant agonist activity. In UMUC3 xenograft-bearing mice, oral gavage treatment with each antiandrogen retarded tumor growth, and only enzalutamide demonstrated a statistically significant suppression compared with mock treatment. Our current data support recent observations indicating the involvement of
Kjaer, Thomas Nordstrøm; Ornstrup, Marie Juul; Poulsen, Morten Møller; Jørgensen, Jens Otto Lunde; Hougaard, David Michael; Cohen, Arieh Sierra; Neghabat, Shadman; Richelsen, Bjørn; Pedersen, Steen Bønløkke
2015-09-01
Resveratrol is a naturally occurring polyphenol with purported inhibitory effects on prostate growth and cancer development. A number of studies have demonstrated that resveratrol reduces prostate growth in animal models and reduces prostate cell growth in vitro. Based on these pre-clinical findings, interest in resveratrol is increasing in relation to the management of benign prostate hyperplasia (BPH) and prostate cancer. So far, no human trials have evaluated the effects of resveratrol on circulating androgens, prostate size, or biochemical markers of prostate size. In a randomized placebo controlled clinical study using two doses of resveratrol (150 mg or 1,000 mg resveratrol daily) for 4 months, we evaluated the effects on prostate size, prostate specific antigen (PSA) and sex steroid hormones in 66 middle-aged men suffering from the metabolic syndrome(MetS). At baseline, prostate size and PSA were positively correlated (R = 0.34, P < 0.007) as was prostate size and age (R = 0.37, P < 0.003). Prostate size did not correlate with testosterone, free testosterone, dihydrotestosterone (DHT), or any other androgen precursor at baseline. The highest dose of resveratrol lowered the serum level of androstenedione 24% (P = 0.052), dehydroepiandrosterone (DHEA) 41% (P < 0.01), and dehydroepiandrosterone-sulphate (DHEAS) 50% (p<0.001), compared to the control group. However, prostate size and levels of PSA, testosterone, free testosterone and DHT remained unchanged. In this population of middle-aged men suffering from MetS, high dose resveratrol (1,000 mg daily) administration for 4 months significantly lowered serum levels of the androgen precursors androstenedione, DHEA and DHEAS, whereas prostate size and circulating levels of PSA, testosterone, free testosterone, and dihydrotestosterone were unaffected. The present study suggests that resveratrol does not affect prostate volume in healthy middle-aged men as measured by PSA levels and CT acquired prostate volumes
Higuchi, Robert I; Thompson, Anthony W; Chen, Jyun-Hung; Caferro, Thomas R; Cummings, Marquis L; Deckhut, Charlotte P; Adams, Mark E; Tegley, Christopher M; Edwards, James P; López, Francisco J; Kallel, E Adam; Karanewsky, Donald S; Schrader, William T; Marschke, Keith B; Zhi, Lin
2007-10-01
A series of androgen receptor modulators based on 8H-[1,4]oxazino[2,3-f]quinolin-8-ones was synthesized and evaluated in an androgen receptor transcriptional activation assay. The most potent analogues from the series exhibited single-digit nanomolar potency in vitro. Compound 18h demonstrated full efficacy in the maintenance of muscle weight, at 10 mg/kg, with reduced activity in prostate weight in an in vivo model of androgen action.
Transcriptional up-regulation of the human androgen receptor by androgen in bone cells.
Wiren, K M; Zhang, X; Chang, C; Keenan, E; Orwoll, E S
1997-06-01
Androgen regulation of androgen receptor (AR) expression has been observed in a variety of tissues, generally as inhibition, and is thought to attenuate cellular responses to androgen. AR is expressed in osteoblasts, the bone-forming cell, suggesting direct actions of androgens on bone. Here we characterized the effect of androgen exposure on AR gene expression in human osteoblastic SaOS-2 and U-2 OS cells. Treatment of osteoblastic cells with the nonaromatizable androgen 5alpha-dihydrotestosterone increased AR steady state messenger RNA levels in a time- and dose-dependent fashion. Reporter assays with 2.3 kilobases of the proximal 5'-flanking region of the human AR promoter linked to the chloramphenicol acetyltransferase gene in transfected cultures showed that up-regulation of AR promoter activity by androgen was time and dose dependent. Treatment with other steroid hormones, including progesterone, 17beta-estradiol, and dexamethasone, was without effect. The antiandrogen hydroxyflutamide completely antagonized androgen up-regulation. Thus, in contrast to many other androgen target tissues, androgen exposure increases steady state AR messenger RNA levels in osteoblasts. This regulation occurs at least partially at the level of transcription, is mediated by the 5'-promoter region of the AR gene, and is dependent on functional AR. These results suggest that physiological concentrations of androgens have significant effects on AR expression in skeletal tissue.
During mammalian sexual differentiation, the androgens, testosterone and dihydrotestosterone are critical for the organization of the male phenotype. In rats, play behavior is sexually dimorphic. Administration of exogenous androgens during the perinatal period results in masculi...
Androgens stimulate early stages of follicular growth in the primate ovary.
Vendola, K A; Zhou, J; Adesanya, O O; Weil, S J; Bondy, C A
1998-01-01
The concept that androgens are atretogenic, derived from murine ovary studies, is difficult to reconcile with the fact that hyperandrogenic women have more developing follicles than normal-cycling women. To evaluate androgen's effects on primate follicular growth and survival, normal-cycling rhesus monkeys were treated with placebo-, testosterone-(T), or dihydrotestosterone-sustained release implants, and ovaries were taken for histological analysis after 3-10 d of treatment. Growing preantral and small antral follicles up to 1 mm in diameter were significantly and progressively increased in number and thecal layer thickness in T-treated monkeys from 3-10 d. Granulosa and thecal cell proliferation, as determined by immunodetection of the Ki67 antigen, were significantly increased in these follicles. Preovulatory follicles (> 1 mm), however, were not increased in number in androgen-treated animals. Follicular atresia was not increased and there were actually significantly fewer apoptotic granulosa cells in the T-treated groups. Dihydrotestosterone treatment had identical effects, indicating that these growth-promoting actions are mediated by the androgen receptor. These findings show that, over the short term at least, androgens are not atretogenic and actually enhance follicular growth and survival in the primate. These new data provide a plausible explanation for the pathogenesis of "polycystic" ovaries in hyperandrogenism. PMID:9637695
Martyniuk, Christopher J; Bissegger, Sonja; Langlois, Valérie S
2013-12-01
The androgen 5 alpha-dihydrotestosterone (DHT) is a steroidogenic metabolite that has received little attention in non-mammalian species. DHT is produced by the reduction of the double-bond of testosterone by a group of enzymes called 5 alpha-reductases of which there can be multiple isoforms (i.e., srd5a1, srd5a2, and srd5a3). Data from amphibians suggest that the expression of the srd5a genes occurs in early development, and continues until adulthood; however insufficient data exist in fish species, where DHT is thought to be relatively biologically inactive. Here, we demonstrate that fathead minnow (FHM; Pimephales promelas) developing embryos and adults express srd5a enzyme isoforms. During FHM embryogenesis, both srd5a1 and srd5a3 mRNA levels were significantly correlated in expression levels while srd5a2 showed a more unique pattern of expression. In adult FHMs, males had significantly higher levels of srd5a2 in the liver and gonad compared to females. In the male and female liver, transcript levels for srd5a2 were more abundant compared to srd5a1 and srd5a3, suggesting a prominent role for srd5a2 in this tissue. Interestingly, the ovary expressed higher mRNA levels of srd5a3 than the testis. Thus, data suggest that srd5a isoforms can show sexually dimorphic expression patterns in fish. We also conducted a literature review of the biological effects observed in embryonic and adult fish and amphibians after treatments with DHT and DHT-related compounds. Treatments with DHT in teleost fishes and amphibians have resulted in unexpected biological responses that are characteristic of both androgens and anti-androgens. For example, in fish DHT can induce vitellogenin in vitro from male and female hepatocytes and can increase 17β-estradiol production from the teleost ovary. We propose, that to generate further understanding of the roles of DHT in non-mammals, studies are needed that (1) address how DHT is synthesized within tissues of fish and amphibians; (2
Androgens and estrogens in benign prostatic hyperplasia: past, present and future
Nicholson, Tristan M.; Ricke, William A.
2011-01-01
Benign prostatic hyperplasia (BPH) and associated lower urinary tract symptoms (LUTS) are common clinical problems in urology. While the precise molecular etiology remains unclear, sex steroids have been implicated in the development and maintenance of BPH. Sufficient data exists linking androgens and androgen receptor pathways to BPH and use of androgen reducing compounds, such as 5α-reductase inhibitors which block the conversion of testosterone into dihydrotestosterone, are a component of the standard of care for men with LUTS attributed to an enlarged prostate. However, BPH is a multifactorial disease and not all men respond well to currently available treatments, suggesting factors other than androgens are involved. Testosterone, the primary circulating androgen in men, can also be metabolized via CYP19/aromatase into the potent estrogen, estradiol-17β. The prostate is an estrogen target tissue and estrogens directly and indirectly affect growth and differentiation of prostate. The precise role of endogenous and exogenous estrogens in directly affecting prostate growth and differentiation in the context of BPH is an understudied area. Estrogens and selective estrogen receptor modulators (SERMs) have been shown to promote or inhibit prostate proliferation signifying potential roles in BPH. Recent research has demonstrated that estrogen receptor signaling pathways may be important in the development and maintenance of BPH and LUTS; however, new models are needed to genetically dissect estrogen regulated molecular mechanisms involved in BPH. More work is needed to identify estrogens and associated signaling pathways in BPH in order to target BPH with dietary and therapeutic SERMs. PMID:21620560
Atmospheric Pressure Photoionization Tandem Mass Spectrometry of Androgens in Prostate Cancer
Lih, Fred Bjørn; Titus, Mark A.; Mohler, James L.; Tomer, Kenneth B.
2010-01-01
Androgen deprivation therapy is the most common treatment option for advanced prostate cancer. Almost all prostate cancers recur during androgen deprivation therapy, and new evidence suggests that androgen receptor activation persists despite castrate levels of circulating androgens. Quantitation of tissue levels of androgens is critical to understanding the mechanism of recurrence of prostate cancer during androgen deprivation therapy. A liquid chromatography atmospheric pressure photoionization tandem mass spectrometric method was developed for quantitation of tissue levels of androgens. Quantitation of the saturated keto-steroids dihydrotestosterone and 5-α-androstanedione required detection of a novel parent ion, [M + 15]+. The nature of this parent ion was explored and the method applied to prostate tissue and cell culture with comparison to results achieved using electrospray ionization. PMID:20560527
Role of Hsp90 in Androgen-Refractory Prostate Cancer
2010-03-01
designed siRNA sequence using Intergrated DNA Technologies RNAi online software tool (IDT, Coralville, IA). The sequence of siRNA specific for...proliferation and production of prostate-specific antigen in androgen-sensitive pros- tatic cancer cells, LNCaP, by dihydrotestosterone. Endocrinology 136
Bhatia, Harpreet; Kumar, Anupama
2016-01-01
The aim of the present study was to investigate if the effects of the androgen, dihydrotestosterone (DHT) on the sexual development in juvenile Murray rainbowfish (Melanotaenia fluviatilis) are canceled out by the anti-androgen, flutamide. Fish (60 days post hatch) were exposed to 250ng/L of DHT, 25μg/L of flutamide (Flu-low), 250μg/L of flutamide (Flu-high), DHT+Flu low and DHT+Flu high. After 35 days of exposure, lengths and weights of the fish were measured and the condition factor (CF) calculated; vitellogenin (VTG) concentrations were measured in tail tissue; sex steroid hormones (17β-estradiol [E2] and 11-keto testosterone [11-KT]) were measured in the head tissue and abdominal regions were used in histological investigation of the gonads. Treatment with DHT reduced the body-length of both male and female fish, an effect which was canceled out by low and high concentrations of flutamide. However, flutamide (low or high) could not nullify the DHT-induced reduction in the CF in either sex. The E2 levels were reduced only in female fish after exposure to DHT but returned to normal after treatment with Flu-high. DHT increased the levels of 11-KT and decreased the E2/11-KT ratio in both sexes. Flu-high, but not Flu-low, could nullify these effects. Both DHT and flutamide (low or high) induced VTG production and this effect persisted when both chemicals were co-administered. Treatment with DHT did not affect gonadal cell development in the testes. However, the female fish treated with DHT contained ovaries in early-vitellogenic stage in comparison to the pre-vitellogenic ovaries in control fish. Co-treatment with flutamide (low or high) resulted in oocyte atresia. The results from the present study suggest that treatment with Flu-high could cancel out DHT-induced effects only on the hormonal profile and body-length in both male and female fish. Juvenile fish co-treated with DHT and flutamide (low or high) had high VTG levels and low CF. In addition, the ovaries
Ko, Hyun-Kyung; Berk, Michael; Chung, Yoon-Mi; Willard, Belinda; Bareja, Rohan; Rubin, Mark; Sboner, Andrea; Sharifi, Nima
2018-01-16
Castration-resistant prostate cancer (CRPC) requires tumors to engage metabolic mechanisms that allow sustained testosterone and/or dihydrotestosterone to stimulate progression. 17β-Hydroxysteroid dehydrogenase type 4 (17βHSD4), encoded by HSD17B4, is thought to inactivate testosterone and dihydrotestosterone by converting them to their respective inert 17-keto steroids. Counterintuitively, HSD17B4 expression increases in CRPC and predicts poor prognosis. Here, we show that, of five alternative splice forms, only isoform 2 encodes an enzyme capable of testosterone and dihydrotestosterone inactivation. In contrast with other transcripts, functional expression of isoform 2 is specifically suppressed in development of CRPC in patients. Genetically silencing isoform 2 shifts the metabolic balance toward 17β-OH androgens (testosterone and dihydrotestosterone), stimulating androgen receptor (AR) and CRPC development. Our studies specifically implicate HSD17B4 isoform 2 loss in lethal prostate cancer. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.
Valdehita, Ana; Fernández-Cruz, María-Luisa; González-Gullón, María Isabel; Becerra-Neira, Eduardo; Delgado, María Mar; García-González, Mari Cruz; Navas, José María
2017-07-01
The use of manure as an agricultural amendment is increasing the release of steroid hormones into the environment. Most research in this field has focused on estrogenic phenomena, with less attention paid to androgenic substances. The present study assessed androgenic activity in broiler manure using in vitro approaches based on cells stably transfected with androgen receptor. Leaching experiments were also performed to observe whether endocrine disruptors present in manure pass through a soil column and potentially reach groundwater. In parallel, an analytical chemistry method was used to determine the contribution of the most important natural androgens to androgenicity. Samplings were performed at 4 farms in 2 seasons. All but 2 samples showed androgen activity. In leakage experiments, however, no androgenic activity was detectable in leachates or in soils after leaching. According to the analytical results, androgenicity can be attributed mainly (but not completely) to androstenedione, and dihydrotestosterone. Similarly to the bioassays, chemical analysis did not reveal the presence of any androgen in leachates or soils. These results point to a rapid degradation of the substances responsible for androgenic activity in soils under the experimental conditions of the present study. However, the long-term effects associated with the constant and intensive application of manure to agricultural land require further attention. Environ Toxicol Chem 2017;36:1746-1754. © 2016 SETAC. © 2016 SETAC.
Martyniuk, Christopher J; Bissegger, Sonja; Langlois, Valérie S
2014-07-01
The androgen 5 alpha-dihydrotestosterone (DHT) is a steroidogenic metabolite that has received little attention in non-mammalian species. DHT is produced by the reduction of the double-bond of testosterone by a group of enzymes called 5 alpha-reductases of which there can be multiple isoforms (i.e., srd5a1, srd5a2, and srd5a3). Data from amphibians suggest that the expression of the srd5a genes occurs in early development, and continues until adulthood; however insufficient data exist in fish species, where DHT is thought to be relatively biologically inactive. Here, we demonstrate that fathead minnow (FHM; Pimephales promelas) developing embryos and adults express srd5a enzyme isoforms. During FHM embryogenesis, both srd5a1 and srd5a3 mRNA levels were significantly correlated in expression levels while srd5a2 showed a more unique pattern of expression. In adult FHMs, males had significantly higher levels of srd5a2 in the liver and gonad compared to females. In the male and female liver, transcript levels for srd5a2 were more abundant compared to srd5a1 and srd5a3, suggesting a prominent role for srd5a2 in this tissue. Interestingly, the ovary expressed higher mRNA levels of srd5a3 than the testis. Thus, data suggest that srd5a isoforms can show sexually dimorphic expression patterns in fish. We also conducted a literature review of the biological effects observed in embryonic and adult fish and amphibians after treatments with DHT and DHT-related compounds. Treatments with DHT in teleost fishes and amphibians have resulted in unexpected biological responses that are characteristic of both androgens and anti-androgens. For example, in fish DHT can induce vitellogenin in vitro from male and female hepatocytes and can increase 17β-estradiol production from the teleost ovary. We propose, that to generate further understanding of the roles of DHT in non-mammals, studies are needed that (1) address how DHT is synthesized within tissues of fish and amphibians; (2
Kaufman, Keith D
2002-12-30
Androgens have profound effects on scalp and body hair in humans. Scalp hair grows constitutively in the absence of androgens, while body hair growth is dependent on the action of androgens. Androgenetic alopecia, referred to as male pattern hair loss (MPHL) in men and female pattern hair loss (FPHL) in women, is due to the progressive miniaturization of scalp hair. Observations in both eunuchs, who have low levels of testicular androgens, and males with genetic 5alpha-reductase (5alphaR) deficiency, who have low levels of dihydrotestosterone (DHT), implicate DHT as a key androgen in the pathogenesis of MPHL in men. The development of finasteride, a type 2-selective 5alphaR inhibitor, further advanced our understanding of the role of DHT in the pathophysiology of scalp alopecia. Controlled clinical trials with finasteride demonstrated improvements in scalp hair growth in treated men associated with reductions in scalp DHT content, and a trend towards reversal of scalp hair miniaturization was evident by histopathologic evaluation of scalp biopsies. In contrast to its beneficial effects in men, finasteride did not improve hair growth in postmenopausal women with FPHL. Histopathological evaluation of scalp biopsies confirmed that finasteride treatment produced no benefit on scalp hair in these women. These findings suggest that MPHL and FPHL are distinct clinical entities, with disparate pathophysiologies. Studies that elucidate the molecular mechanisms by which androgens regulate hair growth would provide greater understanding of these differences. Copyright 2002 Elsevier Science Ireland Ltd.
Of mice and men (and mosquitofish): Antiandrogens and androgens in the environment
Androgens are hormones produced by the gonads and other endocrine organs of all vertebrates. Testosterone, along with its metabolite dihydrotestosterone, is critical for differentiation of the fetal male reproductive tract from an indifferent state, for the development of male tr...
Antihypertensive effects of androgens in conscious, spontaneously hypertensive rats.
Perusquía, Mercedes; Herrera, Nieves; Ferrer, Mercedes; Stallone, John N
2017-03-01
Androgens are vasoactive steroids that induce acute vasodilation in a number of isolated vascular beds from different species, but the effects of these hormones on systemic blood pressure (BP) have been studied little. Although it has been reported that androgens exert systemic hypotensive effects through peripheral vasodilation in normotensive rats, there have not been any reports of systemic hypotensive effects of androgens in animals with hypertension. This study was designed to evaluate the acute effects of testosterone (TES) and its 5-reduced metabolites on systemic BP in hypertensive rats and to test the hypothesis that hypotestosteronemia may be involved in the pathogenesis of hypertension. Chronic, indwelling catheters were implanted in carotid artery and jugular vein of 18-21-week-old male spontaneously hypertensive rats (SHR) and normotensive-control Wistar-Kyoto (WKY) rats, for BP recording and drug administration, respectively. Bolus injections of TES, 5α- or 5β-dihydrotestosterone (5α- and 5β-DHT), were administrated cumulatively to conscious rats at doses of 0.1-100μmolkg -1 min -1 . 5β-DHT was also administrated during the pressor effect of Bay K 8644, an L-type voltage-operated Ca 2+ channel (L-VOCC) agonist. In separate experiments, BP of orchidectomized normotensive male WKY and Wistar rats, with or without androgen-replacement therapy, was evaluated weekly for 10 weeks by tail-cuff plethysmography. TES and its metabolites reduced BP in a dose-dependent manner, while heart rate was reduced with some androgens at the highest doses. The hypotensive effects of androgens were markedly greater in SHR, with a rank order potency of: 5β-DHT>TES>5α-DHT. 5β-DHT, the most potent antihypertensive androgen, abolished the pressor response to Bay K 8644 in SHR. TES deprivation by orchidectomy increased BP in normotensive WKY and Wistar rats, but this hypertension was prevented by TES replacement therapy. BP responses to androgens are androgen structure
Abi Ghanem, Charly; Degerny, Cindy; Hussain, Rashad; Liere, Philippe; Pianos, Antoine; Tourpin, Sophie; Habert, René; Schumacher, Michael
2017-01-01
The oligodendrocyte density is greater and myelin sheaths are thicker in the adult male mouse brain when compared with females. Here, we show that these sex differences emerge during the first 10 postnatal days, precisely at a stage when a late wave of oligodendrocyte progenitor cells arises and starts differentiating. Androgen levels, analyzed by gas chromatography/tandem-mass spectrometry, were higher in males than in females during this period. Treating male pups with flutamide, an androgen receptor (AR) antagonist, or female pups with 5α-dihydrotestosterone (5α-DHT), revealed the importance of postnatal androgens in masculinizing myelin and their persistent effect into adulthood. A key role of the brain AR in establishing the sexual phenotype of myelin was demonstrated by its conditional deletion. Our results uncover a new persistent effect of postnatal AR signaling, with implications for neurodevelopmental disorders and sex differences in multiple sclerosis. PMID:29107990
Androgen biosynthesis in castration-resistant prostate cancer
Penning, Trevor M
2014-01-01
Prostate cancer is the second leading cause of death in adult males in the USA. Recent advances have revealed that the fatal form of this cancer, known as castration-resistant prostate cancer (CRPC), remains hormonally driven despite castrate levels of circulating androgens. CRPC arises as the tumor undergoes adaptation to low levels of androgens by either synthesizing its own androgens (intratumoral androgens) or altering the androgen receptor (AR). This article reviews the major routes to testosterone and dihydrotestosterone synthesis in CRPC cells and examines the enzyme targets and progress in the development of isoform-specific inhibitors that could block intratumoral androgen biosynthesis. Because redundancy exists in these pathways, it is likely that inhibition of a single pathway will lead to upregulation of another so that drug resistance would be anticipated. Drugs that target multiple pathways or bifunctional agents that block intratumoral androgen biosynthesis and antagonize the AR offer the most promise. Optimal use of enzyme inhibitors or AR antagonists to ensure maximal benefits to CRPC patients will also require application of precision molecular medicine to determine whether a tumor in a particular patient will be responsive to these treatments either alone or in combination. PMID:24829267
Jasuja, Ravi; Ulloor, Jagadish; Yengo, Christopher M.; Choong, Karen; Istomin, Andrei Y.; Livesay, Dennis R.; Jacobs, Donald J.; Swerdloff, Ronald S.; Mikšovská, Jaroslava; Larsen, Randy W.; Bhasin, Shalender
2009-01-01
Ligand-induced conformational perturbations in androgen receptor (AR) are important in coactivator recruitment and transactivation. However, molecular rearrangements in AR ligand-binding domain (AR-LBD) associated with agonist binding and their kinetic and thermodynamic parameters are poorly understood. We used steady-state second-derivative absorption and emission spectroscopy, pressure and temperature perturbations, and 4,4′-bis-anilinonaphthalene 8-sulfonate (bis-ANS) partitioning to determine the kinetics and thermodynamics of the conformational changes in AR-LBD after dihydrotestosterone (DHT) binding. In presence of DHT, the second-derivative absorption spectrum showed a red shift and a change in peak-to-peak distance. Emission intensity increased upon DHT binding, and center of spectral mass was blue shifted, denoting conformational changes resulting in more hydrophobic environment for tyrosines and tryptophans within a more compact DHT-bound receptor. In pressure perturbation calorimetry, DHT-induced energetic stabilization increased the Gibbs free energy of unfolding to 8.4 ± 1.3 kcal/mol from 3.5 ± 1.6 kcal/mol. Bis-ANS partitioning studies revealed that upon DHT binding, AR-LBD underwent biphasic rearrangement with a high activation energy (13.4 kcal/mol). An initial, molten globule-like burst phase (k ∼30 sec−1) with greater solvent accessibility was followed by rearrangement (k ∼0.01 sec−1), leading to a more compact conformation than apo-AR-LBD. Molecular simulations demonstrated unique sensitivity of tyrosine and tryptophan residues during pressure unfolding with rearrangement of residues in the coactivator recruitment surfaces distant from the ligand-binding pocket. In conclusion, DHT binding leads to energetic stabilization of AR-LBD domain and substantial rearrangement of residues distant from the ligand-binding pocket. DHT binding to AR-LBD involves biphasic receptor rearrangement including population of a molten globule
The neural androgen receptor: a therapeutic target for myelin repair in chronic demyelination
Hussain, Rashad; Ghoumari, Abdel M.; Bielecki, Bartosz; Steibel, Jérôme; Boehm, Nelly; Liere, Philippe; Macklin, Wendy B.; Kumar, Narender; Habert, René; Mhaouty-Kodja, Sakina; Tronche, François; Sitruk-Ware, Regine
2013-01-01
Myelin regeneration is a major therapeutic goal in demyelinating diseases, and the failure to remyelinate rapidly has profound consequences for the health of axons and for brain function. However, there is no efficient treatment for stimulating myelin repair, and current therapies are limited to anti-inflammatory agents. Males are less likely to develop multiple sclerosis than females, but often have a more severe disease course and reach disability milestones at an earlier age than females, and these observations have spurred interest in the potential protective effects of androgens. Here, we demonstrate that testosterone treatment efficiently stimulates the formation of new myelin and reverses myelin damage in chronic demyelinated brain lesions, resulting from the long-term administration of cuprizone, which is toxic for oligodendrocytes. In addition to the strong effect of testosterone on myelin repair, the number of activated astrocytes and microglial cells returned to low control levels, indicating a reduction of neuroinflammatory responses. We also identify the neural androgen receptor as a novel therapeutic target for myelin recovery. After the acute demyelination of cerebellar slices in organotypic culture, the remyelinating actions of testosterone could be mimicked by 5α-dihydrotestosterone, a metabolite that is not converted to oestrogens, and blocked by the androgen receptor antagonist flutamide. Testosterone treatment also failed to promote remyelination after chronic cuprizone-induced demyelination in mice with a non-functional androgen receptor. Importantly, testosterone did not stimulate the formation of new myelin sheaths after specific knockout of the androgen receptor in neurons and macroglial cells. Thus, the neural brain androgen receptor is required for the remyelination effect of testosterone, whereas the presence of the receptor in microglia and in peripheral tissues is not sufficient to enhance remyelination. The potent synthetic
Miyoshi, Y; Uemura, H; Suzuki, K; Shibata, Y; Honma, S; Harada, M; Kubota, Y
2017-03-01
There has been no consensus on the role of serum androgen concentrations in prostate cancer detection in men with prostate-specific antigen levels of 3-10 ng/mL. In this study, testosterone and dihydrotestosterone concentrations in blood were examined by a newly developed method using ultrasensitive liquid chromatography with two serially linked mass spectrometers (LC-MS/MS). We investigated the correlation between serum androgen levels and Gleason scores at biopsy. We analyzed data of 157 men with a total prostate-specific antigen range of 3-10 ng/mL who underwent initial systematic prostate needle biopsy for suspected prostate cancer between April 2000 and July 2003. Peripheral blood testosterone and dihydrotestosterone concentrations were determined by LC-MS/MS. Blood levels of testosterone and dihydrotestosterone were compared with pathological findings by multivariate analyses. Median values of prostate-specific antigen and prostate volume measured by ultrasound were 5.7 ng/mL and 31.4 cm 3 , respectively. Benign prostatic hyperplasia was diagnosed in 97 patients (61.8%), and prostate cancer was diagnosed in 60 (38.2%) patients, including 31 (19.7%) patients with a Gleason score of 6 and 29 (18.5%) patients with a Gleason score of 7-10. Median values of testosterone and dihydrotestosterone in blood were 3798.7 and 371.7 pg/mL, respectively. There was a strong correlation between serum testosterone and dihydrotestosterone. In multivariate analysis, age, prostate volume, and serum dihydrotestosterone were significant predictors of benign prostatic hyperplasia or prostate cancer with a Gleason score of 6. The area under the receiver operating characteristics curve for age, prostate volume, and serum dihydrotestosterone were 0.67, 0.67, and 0.67, respectively . We confirmed that high dihydrotestosterone blood levels can predict benign prostatic hyperplasia or prostate cancer with a Gleason score of 6 in men with prostate-specific antigen levels of 3-10
Zhang, Xuqing; Li, Xiaojie; Allan, George F; Sbriscia, Tifanie; Linton, Olivia; Lundeen, Scott G; Sui, Zhihua
2007-08-09
A novel series of pyrazolines 2 have been designed, synthesized, and evaluated by in vivo screening as tissue-selective androgen receptor modulators (SARMs). Structure-activity relationships (SAR) were investigated at the R1 to R6 positions as well as the core pyrazoline ring and the anilide linker. Overall, strong electron-withdrawing groups at the R1 and R2 positions and a small group at the R5 and R6 position are optimal for AR agonist activity. The (S)-isomer of 7c exhibits more potent AR agonist activity than the corresponding (R)-isomer. (S)-7c exhibited an overall partial androgenic effect but full anabolic effect via oral administration in castrated rats. It demonstrated a noticeable antiandrogenic effect on prostate in intact rats with endogenous testosterone. Thus, (S)-7c is a tissue-selective nonsteroidal androgen receptor modulator with agonist activity on muscle and mixed agonist and antagonist activity on prostate.
Paliouras, Miltiadis; Diamandis, Eleftherios P
2008-06-01
The androgen receptor (AR) plays an important role in early prostate cancer by activating transcription of a number of genes participating in cell proliferation and growth and cancer progression. However, as the cancer progresses, prostate cancer cells transform from an androgen-dependent to an androgen-independent state. Androgen-independent prostate cancer can manifest itself in several forms, including a percentage of cancers that show reduced levels of prostate-specific antigen (PSA) and can progress without the need for the ligand or active receptor. Therefore, our goal was to examine the role of intracellular signaling pathways in an androgen-independent prostate cancer in vitro model. Using the cell line PC3(AR)(2), we stimulated cells with 5-alpha-dihydrotestosterone (DHT) and epidermal growth factor (EGF) and then analyzed PSA expression. We observed lower PSA expression when cells were jointly stimulated with DHT and EGF, and this was associated with an increase in AKT activity. We examined the role of AKT in AR activity and PSA expression by creating stable PC3(AR)(2) cell lines transfected with a PI3K-Ras-effector loop mutant. These cell lines showed lower DHT-stimulated PSA expression that correlated to changes in the phosphorylated state of AR. Therefore, we propose an in vitro androgen-independent model in which a PI3K/AKT activity threshold and subsequent AR transactivation regulate PSA expression.
Attardi, Barbara J.; Page, Stephanie T.; Hild, Sheri A.; Coss, Christopher C.; Matsumoto, Alvin M.
2009-01-01
Bolandiol is a synthetic anabolic steroid that increases lean body mass and bone mineral density without significant stimulation of sex accessory glands in castrate adult male rats. Since bolandiol suppresses gonadotropins and endogenous testosterone (T) production, we investigated its mechanism of action. We compared the potency of bolandiol in vitro and in vivo with T, 5α-dihydrotestosterone (DHT), 19-nortestosterone (19-NT) and estradiol (E2). Bolandiol bound with lower affinity to the recombinant rat androgen receptor (AR) than the other androgens and had low, but measurable, affinity for recombinant human progestin receptors (PR-A, PR-B), and estrogen receptors (ERα and β-1). Functional agonist activity was assessed in transcription assays mediated by AR, PR, or ER. Bolandiol was stimulatory in all these assays, but only 4–9% as potent as T, DHT, and 19-NT via AR, 1% as potent as progesterone via PR, and 3% and 1% as potent as E2 acting through ERα or ERβ, respectively. In immature castrate rats, bolandiol was equipotent to T in stimulating growth of the levator ani muscle but less potent than T in stimulating growth of the sex accessory glands. Bolandiol also stimulated uterine weight increases in immature female rats, which were partly blocked by ICI 182,780, but it was not aromatized in vitro by recombinant human aromatase. In contrast to T, stimulation of sex accessory gland weights by bolandiol was not inhibited by concomitant treatment with the dual 5α-reductase inhibitor dutasteride. As bolandiol exhibits tissue selectivity in vivo, it may act via AR, PR, and/or ER, utilize alternative signaling pathway(s) or transcriptional coregulators, and/or be metabolized to a more potent selective steroid. PMID:19941958
Androgen-estrogen synergy in rat levator ani muscle Glucose-6-phosphate dehydrogenase
NASA Technical Reports Server (NTRS)
Max, S. R.
1984-01-01
The effects of castration and hormone administration on the activity of glucose-6-phosphate dehydrogenase in the rat levator ani muscle were studied. Castration caused a decrease in enzyme activity and in wet weight of the levator ani muscle. Chronic administration of testosterone propionate increased glucose-6-phosphate dehydrogenase activity in the levator ani muscle of castrated rats; the magnitude of the recovery of enzyme activity was related to the length of time of exposure to testosterone propionate after castration as well as to the length of time the animals were castrated. The longer the period of castration before exposure to testosterone propionate, the greater the effect. This result may be related to previously reported castration-mediated increases in androgen receptor binding in muscle. Dihydrotestosterone was less effective than testosterone propionate in enhancing glucose-6-phosphate dehydrogenase activity in the levator ani muscle from castrated rats; estradiol-17-beta alone was ineffective. Combined treatment with estradiol-17-beta and dihydrotestosterone, however, was as effective as testosterone alone. Thus, androgens and estrogens may exert synergistic effects on levator ani muscle.
Genomic and non-genomic effects of androgens in the cardiovascular system: clinical implications
Lucas-Herald, Angela K.; Alves-Lopes, Rheure; Montezano, Augusto C.; Ahmed, S. Faisal
2017-01-01
The principle steroidal androgens are testosterone and its metabolite 5α-dihydrotestosterone (DHT), which is converted from testosterone by the enzyme 5α-reductase. Through the classic pathway with androgens crossing the plasma membrane and binding to the androgen receptor (AR) or via mechanisms independent of the ligand-dependent transactivation function of nuclear receptors, testosterone induces genomic and non-genomic effects respectively. AR is widely distributed in several tissues, including vascular endothelial and smooth muscle cells. Androgens are essential for many developmental and physiological processes, especially in male reproductive tissues. It is now clear that androgens have multiple actions besides sex differentiation and sexual maturation and that many physiological systems are influenced by androgens, including regulation of cardiovascular function [nitric oxide (NO) release, Ca2+ mobilization, vascular apoptosis, hypertrophy, calcification, senescence and reactive oxygen species (ROS) generation]. This review focuses on evidence indicating that interplay between genomic and non-genomic actions of testosterone may influence cardiovascular function. PMID:28645930
Reversal of androgen inhibition of estrogen-activated sexual behavior by cholinergic agents.
Dohanich, G P; Cada, D A
1989-12-01
Androgens have been found to inhibit lordosis activated by estrogen treatment of ovariectomized female rats. In the present experiments, dihydrotestosterone propionate (200 micrograms for 3 days) inhibited the incidence of lordosis in ovariectomized females treated with estradiol benzoate (1 microgram for 3 days). This inhibition of lordosis was reversed 15 min after bilateral intraventricular infusion of physostigmine (10 micrograms/cannula), an acetylcholinesterase inhibitor, or carbachol (0.5 microgram/cannula), a cholinergic receptor agonist. This reversal of inhibition appears to be mediated by cholinergic muscarinic receptors since pretreatment with scopolamine (4 mg/kg, ip), a muscarinic receptor blocker, prevented the reversal of androgen inhibition by physostigmine. These results indicate that androgens may inhibit estrogen-activated lordosis through interference with central cholinergic muscarinic mechanisms.
Development of Selective Androgen Receptor Modulators (SARMs)
Narayanan, Ramesh; Coss, Christopher C.; Dalton, James T.
2018-01-01
The Androgen Receptor (AR), a member of the steroid hormone receptor family, plays important roles in the physiology and pathology of diverse tissues. AR ligands, which include circulating testosterone and locally synthesized dihydrotestosterone, bind to and activate the AR to elicit their effects. Ubiquitous expression of the AR, metabolism and cross reactivity with other receptors limit broad therapeutic utilization of steroidal androgens. However, the discovery of selective androgen receptor modulators (SARMs) and other tissue-selective nuclear hormone receptor modulators that activate their cognate receptors in a tissue-selective manner provides an opportunity to promote the beneficial effects of androgens and other hormones in target tissues with greatly reduced unwanted side-effects. In the last two decades, significant resources have been dedicated to the discovery and biological characterization of SARMs in an effort to harness the untapped potential of the AR. SARMs have been proposed as treatments of choice for various diseases, including muscle-wasting, breast cancer, and osteoporosis. This review provides insight into the evolution of SARMs from proof-of-concept agents to the cusp of therapeutic use in less than two decades, while covering contemporary views of their mechanisms of action and therapeutic benefits. PMID:28624515
Abstract
The discovery of xenobiotics which interfere with androgen activity has highlighted the need to assess chemicals for their ability to modulate dihydrotestosterone (DHT)-receptor binding. Previous test systems have used cells transfected with plasmid containing a rep...
Poniah, Prevathe; Mohamed, Zahurin; Apalasamy, Yamunah Devi; Mohd Zain, Shamsul; Kuppusamy, Shanggar; Razack, Azad HA
2015-01-01
Androgens are involved in prostate cancer (PCa) cell growth. Genes involved in androgen metabolism mediate key steps in sex steroid metabolism. This study attempted to investigate whether single nucleotide polymorphisms (SNPs) in the androgen metabolism pathway are associated with PCa risk in low incidence Asian ethnic groups. We genotyped 172 Malaysian subjects for cytochrome P450 family 17 (CYP17A1), steroid-5-alpha-reductase, polypeptide 1 and 2 (SRD5A1 and SRD5A2), and insulin-like growth factor 1 (IGF-1) genes of the androgen metabolism pathway and assessed the testosterone, dihydrotestosterone and IGF-1 levels. SNPs in the CYP17A1, SRD5A1, SRD5A2, and IGF-1 genes were genotyped using real-time polymerase chain reaction. Although we did not find significant association between SNPs analysed in this study with PCa risk, we observed however, significant association between androgen levels and the IGF-1 and several SNPs. Men carrying the GG genotype for SNP rs1004467 (CYP17A1) had significantly elevated testosterone (P = 0.012) and dihydrotestosterone (DHT) levels (P = 0.024) as compared to carriers of the A allele. The rs518673 of the SRD5A1 was associated with prostate specific antigen (PSA) levels. Our findings suggest CYP17A1 rs1004467 SNP is associated with testosterone and DHT levels indicating the importance of this gene in influencing androgen levels in the circulatory system of PCa patients, hence could be used as a potential marker in PCa assessment. PMID:26770559
Poniah, Prevathe; Mohamed, Zahurin; Apalasamy, Yamunah Devi; Mohd Zain, Shamsul; Kuppusamy, Shanggar; Razack, Azad Ha
2015-01-01
Androgens are involved in prostate cancer (PCa) cell growth. Genes involved in androgen metabolism mediate key steps in sex steroid metabolism. This study attempted to investigate whether single nucleotide polymorphisms (SNPs) in the androgen metabolism pathway are associated with PCa risk in low incidence Asian ethnic groups. We genotyped 172 Malaysian subjects for cytochrome P450 family 17 (CYP17A1), steroid-5-alpha-reductase, polypeptide 1 and 2 (SRD5A1 and SRD5A2), and insulin-like growth factor 1 (IGF-1) genes of the androgen metabolism pathway and assessed the testosterone, dihydrotestosterone and IGF-1 levels. SNPs in the CYP17A1, SRD5A1, SRD5A2, and IGF-1 genes were genotyped using real-time polymerase chain reaction. Although we did not find significant association between SNPs analysed in this study with PCa risk, we observed however, significant association between androgen levels and the IGF-1 and several SNPs. Men carrying the GG genotype for SNP rs1004467 (CYP17A1) had significantly elevated testosterone (P = 0.012) and dihydrotestosterone (DHT) levels (P = 0.024) as compared to carriers of the A allele. The rs518673 of the SRD5A1 was associated with prostate specific antigen (PSA) levels. Our findings suggest CYP17A1 rs1004467 SNP is associated with testosterone and DHT levels indicating the importance of this gene in influencing androgen levels in the circulatory system of PCa patients, hence could be used as a potential marker in PCa assessment.
Effect of Cuscuta reflexa Roxb on androgen-induced alopecia.
Pandit, Shweta; Chauhan, Nagendra Singh; Dixit, V K
2008-09-01
Alopecia is a psychologically distressing condition. Androgenetic alopecia, which affects millions of men and women, is an androgen-driven disorder. Here, Cuscuta reflexa Roxb is evaluated for hair growth activity in androgen-induced alopecia. Petroleum ether extract of C. reflexa was studied for its hair growth-promoting activity. Alopecia was induced in albino mice by testosterone administration for 20 days. Its inhibition by simultaneous administration of extract was evaluated using follicular density, anagen/telogen ratio, and microscopic observation of skin sections. To investigate the mechanism of observed activity, in vitro experiments were performed to study the effect of extract and its major component on activity of 5alpha-reductase enzyme. Petroleum ether extract of C. reflexa exhibited promising hair growth-promoting activity as reflected from follicular density, anagen/telogen ratio, and skin sections. Inhibition of 5alpha-reductase activity by extract and isolate suggest that the extract reversed androgen-induced alopecia by inhibiting conversion of testosterone to dihydrotestosterone. The petroleum ether extract of C. reflexa and its isolate is useful in treatment of androgen-induced alopecia by inhibiting the enzyme 5alpha-reductase.
Barthold, Julia S.; Wang, Yanping; Robbins, Alan; Pike, Jack; McDowell, Erin; Johnson, Kamin J.; McCahan, Suzanne M.
2013-01-01
ABSTRACT Androgens and insulin-like 3 (INSL3) are required for development of the fetal gubernaculum and testicular descent. Previous studies suggested that the INSL3-exposed fetal gubernacular transcriptome is enriched for genes involved in neural pathways. In the present study, we profiled the transcriptome of fetal gubernaculum explants exposed to dihydrotestosterone (DHT) and compared this response to that with INSL3. We exposed fetal (Embryonic Day 17) rat gubernacula to DHT for 24 h (10 and 30 nM) or 6 h (1 and 10 nM) in organ culture and analyzed gene expression relative to that of vehicle-treated controls using Affymetrix arrays. Results were annotated using functional, pathway, and promoter analyses and independently validated for selected transcripts using quantitative RT-PCR (qRT-PCR). Transcripts were differentially expressed after 24 h but not 6 h. Most highly overrepresented functional categories included those related to gene expression, skeletal and muscular development and function, and Wnt signaling. Promoter response elements enriched in the DHT-specific transcriptome included consensus sequences for c-ETS1, ELK1, CREB, CRE-BP1/c-June, NRF2, and USF. We observed that 55% of DHT probe sets were also differentially expressed after INSL3 exposure and that the direction of change was the same in 96%. The qRT-PCR results confirmed that DHT increased expression of the INSL3-responsive genes Crlf1 and Chrdl2 but reduced expression of Wnt4. We also validated reduced Tgfb2 and Cxcl12 and increased Slit3 expression following DHT exposure. These data suggest a robust overlap in the DHT- and INSL3-regulated transcriptome that may be mediated in part by CREB signaling and a common Wnt pathway response for both hormones in the fetal gubernaculum. PMID:24174575
Androgen responsiveness of the new human endometrial cancer cell line MFE-296.
Hackenberg, R; Beck, S; Filmer, A; Hushmand Nia, A; Kunzmann, R; Koch, M; Slater, E P; Schulz, K D
1994-04-01
MFE-296 endometrial cancer cells express androgen receptors in vitro. These cells, which are tumorigenic in nude mice, are derived from a moderately differentiated human endometrial adenocarcinoma. They express vimentin and the cytokeratins 7, 8, 18, and 19. Karyotyping revealed near-tetraploidy for most of the cells. No marker chromosomes were observed. DNA analyses confirmed the genetic identity of the cell line and the patient from whom the cell line was derived. Proliferation of MFE-296 cells was inhibited by the progestin R5020 and the androgen dihydrotestosterone (DHT). The inhibition of proliferation by DHT was antagonized by the antiandrogen Casodex, demonstrating the involvement of the androgen receptor. Androgen binding was determined at 22,000 binding sites per cell using a whole-cell assay (KD = 0.05 nM) and 30 fmol/mg protein with the dextran charcoal method; 7 fmol/mg protein of progesterone receptors were found, whereas estrogen receptors were below 5 fmol/mg protein. The androgen receptor was functionally intact, as demonstrated by transfection experiments with a reporter-gene construct, containing an androgen-responsive element. In MFE-296 cells the content of the androgen receptor was up-regulated by its own ligand.
Sphingosine kinase-1 mediates androgen-induced osteoblast cell growth
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martin, Claire; Universite de Toulouse, UPS, IPBS, Toulouse F-31000; Lafosse, Jean-Michel
Herein we report that the lipid kinase sphingosine kinase-1 (SphK1) is instrumental in mediating androgen-induced cell proliferation in osteoblasts. Dihydrotestosterone (DHT) triggered cell growth in steroid-deprived MC3T3 cells, which was associated with a rapid stimulation of SphK1 and activation of both Akt and ERK signaling pathways. This mechanism relied on functional androgen receptor/PI3K/Akt nongenotropic signaling as pharmacological antagonists could block SphK1 stimulation by DHT and its consequences. Finally, SphK1 inhibition not only abrogated DHT-induced ERK activation but also blocked cell proliferation, while ERK inhibition had no impact, suggesting that SphK1 was critical for DHT signaling yet independently of the ERK.
Genomic and non-genomic effects of androgens in the cardiovascular system: clinical implications.
Lucas-Herald, Angela K; Alves-Lopes, Rheure; Montezano, Augusto C; Ahmed, S Faisal; Touyz, Rhian M
2017-07-01
The principle steroidal androgens are testosterone and its metabolite 5α-dihydrotestosterone (DHT), which is converted from testosterone by the enzyme 5α-reductase. Through the classic pathway with androgens crossing the plasma membrane and binding to the androgen receptor (AR) or via mechanisms independent of the ligand-dependent transactivation function of nuclear receptors, testosterone induces genomic and non-genomic effects respectively. AR is widely distributed in several tissues, including vascular endothelial and smooth muscle cells. Androgens are essential for many developmental and physiological processes, especially in male reproductive tissues. It is now clear that androgens have multiple actions besides sex differentiation and sexual maturation and that many physiological systems are influenced by androgens, including regulation of cardiovascular function [nitric oxide (NO) release, Ca 2+ mobilization, vascular apoptosis, hypertrophy, calcification, senescence and reactive oxygen species (ROS) generation]. This review focuses on evidence indicating that interplay between genomic and non-genomic actions of testosterone may influence cardiovascular function. © 2017 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.
Welty, J.L.; Belthoff, J.R.; Egbert, J.; Schwabl, H.
2012-01-01
Increases in yolk androgens within and among avian clutches have been correlated with decreased incubation time, increased aggression within a nest, increased begging behaviour, decreased immune response, and decreased life span. Although the mechanisms that lead to variability in yolk androgens within and between clutches are not completely known, yolk androgens can be a function of both social and environmental conditions. We were interested in if and how nesting density, laying date, and laying order influenced yolk androgens in Western Burrowing Owls (Athene cunicularia hypugaea (Bonaparte, 1825)) in which nest density varies considerably. In 2006 and 2007, we used radioimmunoassay to quantify the concentrations of testosterone, 5a-dihydrotestosterone, and androstenedione in the egg yolks from one early and one latelaid egg in 47 nests of Burrowing Owls located in the Morley Nelson Snake River Birds of Prey National Conservation Area in southern Idaho. Nesting density had no detectable effect on yolk androgens. Yolk androgens varied temporally and peaked in the middle of the laying season while being low before and after this time period. Within nests, late-laid eggs had higher testosterone and dihydrotestosterone than early-laid eggs; adrostendione exhibited a similar pattern in one but not both years of our study. It is possible that the seasonal pattern in yolk androgens that we observed is related to aspects of mate quality for females or declining chances of fledging success for later nesting females, whereas rises in egg androgens between early and late eggs within clutches could reflect a mechanism to assist nestlings from late-laid eggs that hatch one to several days after their siblings to better compete for resources within the nest or promote survival in the presence of larger siblings.
Jeong, Soo-Jin; Choi, Ji-Yoon; Dong, Mi-Sook; Seo, Chang-Seob; Shin, Hyeun-Kyoo
2017-01-01
The androgen comprises a group of hormones that play roles in male reproductive activity as well as personal characteristics. We investigated the androgenic activity of various herbal medicines in human prostate cancer 22Rv1 cells. Herbal extracts of Trichosanthes kirilowii (TK), Asarum sieboldii (AS), Sanguisorba officinalis (SO), and Xanthium strumarium (XS) were selected to have androgenic effects based on a preliminary in vitro screening system. TK, AS, SO, and XS enhanced the proliferation of 22Rv1 cells without having cytotoxic effects. All tested herbal extracts increased androgen receptor (AR)-induced transcriptional activity in the absence or presence of dihydrotestosterone (DHT). In an AR-binding assay, TK, but not AS, SO, or XS, produced a significant inhibition of AR binding activity, indicating it has androgenic activity. Additionally, TK treatment positively regulated mRNA expression of the AR-related molecular targets prostate-specific antigen (PSA) and kallikrein 2 (KLK2) compared with untreated control. Taken together, TK-enhanced AR-mediated transcriptional activity might be an attractive candidate drug for treating androgen-related diseases. Trichosantheskirilowii (TK), Asarumsieboldii (AS), Sanguisorbaofficinalis (SO), and Xanthium strumarium (XS) enhanced the proliferation of 22Rv1 cells without having cytotoxic effects.TK, AS, SO, and XS increased androgen receptor (AR)-induced transcriptional activity.TK, but not AS, SO, or XS, produced a significant inhibition against AR-binding activity.TK treatment positively regulated mRNA expression of the AR-related molecular targets prostate-specific antigen and kallikrein 2. Abbreviations used: BPH: benign prostatic hyperplasia; AR: androgen receptor; DHT: dihydrotestosterone; PSA: prostate-specific antigen; TK: Trichosanthes kirilowii; AS: Asarum sieboldii; SO: Sanguisorba officinalis; XS: Xanthium strumarium; ATCC: American Type Culture Collection; FBS: fetal bovine serum; PBS: phosphate
Jeong, Soo-Jin; Choi, Ji-Yoon; Dong, Mi-Sook; Seo, Chang-Seob; Shin, Hyeun-Kyoo
2017-01-01
Background: The androgen comprises a group of hormones that play roles in male reproductive activity as well as personal characteristics. Objective: We investigated the androgenic activity of various herbal medicines in human prostate cancer 22Rv1 cells. Materials and Methods: Herbal extracts of Trichosanthes kirilowii (TK), Asarum sieboldii (AS), Sanguisorba officinalis (SO), and Xanthium strumarium (XS) were selected to have androgenic effects based on a preliminary in vitro screening system. Results: TK, AS, SO, and XS enhanced the proliferation of 22Rv1 cells without having cytotoxic effects. All tested herbal extracts increased androgen receptor (AR)-induced transcriptional activity in the absence or presence of dihydrotestosterone (DHT). In an AR-binding assay, TK, but not AS, SO, or XS, produced a significant inhibition of AR binding activity, indicating it has androgenic activity. Additionally, TK treatment positively regulated mRNA expression of the AR-related molecular targets prostate-specific antigen (PSA) and kallikrein 2 (KLK2) compared with untreated control. Conclusion: Taken together, TK-enhanced AR-mediated transcriptional activity might be an attractive candidate drug for treating androgen-related diseases. SUMMARY Trichosantheskirilowii (TK), Asarumsieboldii (AS), Sanguisorbaofficinalis (SO), and Xanthium strumarium (XS) enhanced the proliferation of 22Rv1 cells without having cytotoxic effects.TK, AS, SO, and XS increased androgen receptor (AR)-induced transcriptional activity.TK, but not AS, SO, or XS, produced a significant inhibition against AR-binding activity.TK treatment positively regulated mRNA expression of the AR-related molecular targets prostate-specific antigen and kallikrein 2. Abbreviations used: BPH: benign prostatic hyperplasia; AR: androgen receptor; DHT: dihydrotestosterone; PSA: prostate-specific antigen; TK: Trichosanthes kirilowii; AS: Asarum sieboldii; SO: Sanguisorba officinalis; XS: Xanthium strumarium; ATCC: American
Androgen Receptor Content of the Normal and Hyperplastic Canine Prostate
Shain, Sydney A.; Boesel, Robert W.
1978-01-01
A procedure was developed for measurement of androgen receptors in cytoplasmic extracts of prostates from intact dogs. The protocol utilized exchange saturation analysis at 15°C employing the synthetic androgen R1881 (17β-hydroxy-17α-methylestra-4,9,11-trien-3-one) as the ligand probe and quantitatively detected total cytoplasmic androgen receptor (Rc, androgen-free receptor, and RcA, androgen-occupied receptor) present at the initiation of the assay. This protocol was employed in conjunction with a tissue mince saturation analysis procedure (for quantitation of nuclear androgen receptor) to quantitate total androgen receptor content of normal and hyperplastic prostates obtained from young (2.5- or 4.6-yr old) and aged (12.5-yr old) purebred dogs of known birth date. The total cytoplasmic androgen receptor content (picomoles per prostate) of hyperplastic prostates was 4.6-fold greater than that of normal prostates. The total nuclear androgen receptor content of hyperplastic prostates (picomoles per prostate measured in crude nuclear preparations) was either 5.0- (4.6-yr-old dogs) or 7.8-fold (2.5-yr-old dogs) greater than that of normal prostates. However, androgen receptor content per cell was identical for hyperplastic and normal canine prostates, with the exception that nuclear androgen receptor was diminished in prostates from 2.5-yr-old dogs. The cell content per gram dry weight was identical for hyperplastic and normal canine prostates. We conclude that canine prostate hyperplasia is characterized by coordinate proliferation of androgen receptor-positive and androgen receptor-negative cells and is not a consequence of increased accumulation of 5α-dihydrotestosterone due to proliferation of androgen receptors per prostate cell. PMID:76635
Price, P; Wass, J A; Griffin, J E; Leshin, M; Savage, M O; Large, D M; Bu'Lock, D E; Anderson, D C; Wilson, J D; Besser, G M
1984-10-01
We describe the clinical and biochemical features of six men with male pseudohermaphroditism due to androgen resistance. Each of the subjects had male-gender behavior but incomplete virilization. The underlying defects in androgen metabolism were defined by studies of the 5 alpha-reductase enzyme and the androgen receptor in fibroblasts cultured from biopsies of genital skin. Four of the six have 5 alpha-reductase deficiency, and two have defects of the androgen receptor (the Reifenstein syndrome). The responses of these men to androgen treatment were assessed by monitoring nitrogen balance, plasma luteinizing hormone (LH) values, and clinical parameters of virilization including penile growth, potency and ejaculatory volume, muscle bulk, and growth of body and facial hair. In all of the subjects with 5 alpha-reductase deficiency and one man with the Reifenstein syndrome significant response occurred, as evidence by nitrogen retention, lowered plasma LH levels, and improved virilization, with doses of parenteral testosterone esters that raised plasma testosterone levels above the normal male range and brought plasma dihydrotestosterone levels into the normal male range. The subject who did not respond with clinical virilization nevertheless showed nitrogen retention in response to acute testosterone administration. This patient had a profound deficiency of the androgen receptor, whereas the man with a receptor defect who did respond clinically to therapy had normal amounts of a qualitatively abnormal receptor. We conclude that high dose androgen therapy may be of benefit in improving virilization, self-image, and sexual performance in subjects with 5 alpha-reductase deficiency who have male-gender behavior and in some subjects with defects of the androgen receptor.
Opoku-Acheampong, Alexander B.; Penugonda, Kavitha; Lindshield, Brian L.
2016-01-01
Saw palmetto supplements (SPS) are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP) SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP) SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP) SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n = 3; p < 0.05). Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n = 4), HLLP, HLHP, and HMLP SPS (n = 6) groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p < 0.05). Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth. PMID:27272436
Opoku-Acheampong, Alexander B; Penugonda, Kavitha; Lindshield, Brian L
2016-01-01
Saw palmetto supplements (SPS) are commonly consumed by men with prostate cancer. We investigated whether SPS fatty acids and phytosterols concentrations determine their growth-inhibitory action in androgen-sensitive LNCaP cells and hamster flank organs. High long-chain fatty acids-low phytosterols (HLLP) SPS ≥ 750 nM with testosterone significantly increased and ≥500 nM with dihydrotestosterone significantly decreased LNCaP cell number. High long-chain fatty acids-high phytosterols (HLHP) SPS ≥ 500 nM with dihydrotestosterone and high medium-chain fatty acids-low phytosterols (HMLP) SPS ≥ 750 nM or with androgens significantly decreased LNCaP cell number (n = 3; p < 0.05). Five- to six-week-old, castrated male Syrian hamsters were randomized to control (n = 4), HLLP, HLHP, and HMLP SPS (n = 6) groups. Testosterone or dihydrotestosterone was applied topically daily for 21 days to the right flank organ; the left flank organ was treated with ethanol and served as the control. Thirty minutes later, SPS or ethanol was applied to each flank organ in treatment and control groups, respectively. SPS treatments caused a notable but nonsignificant reduction in the difference between left and right flank organ growth in testosterone-treated SPS groups compared to the control. The same level of inhibition was not seen in dihydrotestosterone-treated SPS groups (p < 0.05). Results may suggest that SPS inhibit 5α-reductase thereby preventing hamster flank organ growth.
Effect of propofol on androgen receptor activity in prostate cancer cells.
Tatsumi, Kenichiro; Hirotsu, Akiko; Daijo, Hiroki; Matsuyama, Tomonori; Terada, Naoki; Tanaka, Tomoharu
2017-08-15
Androgen receptor is a nuclear receptor and transcription factor activated by androgenic hormones. Androgen receptor activity plays a pivotal role in the development and progression of prostate cancer. Although accumulating evidence suggests that general anesthetics, including opioids, affect cancer cell growth and impact patient prognosis, the effect of those drugs on androgen receptor in prostate cancer is not clear. The purpose of this study was to investigate the effect of the general anesthetic propofol on androgen receptor activity in prostate cancer cells. An androgen-dependent human prostate cancer cell line (LNCaP) was stimulated with dihydrotestosterone (DHT) and exposed to propofol. The induction of androgen receptor target genes was investigated using real-time reverse transcription polymerase chain reaction, and androgen receptor protein levels and localization patterns were analyzed using immunoblotting and immunofluorescence assays. The effect of propofol on the proliferation of LNCaP cells was analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Propofol significantly inhibited DHT-induced expression of androgen receptor target genes in a dose- and time-dependent manner, and immunoblotting and immunofluorescence assays indicated that propofol suppressed nuclear levels of androgen receptor proteins. Exposure to propofol for 24h suppressed the proliferation of LNCaP cells, whereas 4h of exposure did not exert significant effects. Together, our results indicate that propofol suppresses nuclear androgen receptor protein levels, and inhibits androgen receptor transcriptional activity and proliferation in LNCaP cells. Copyright © 2017 Elsevier B.V. All rights reserved.
Numazawa, M; Yoshimura, A; Oshibe, M
1998-01-01
To gain insight into the relationships between the aromatase inhibitory activity of 6-alkyl-substituted androgens, potent competitive inhibitors, and their ability to serve as a substrate of aromatase, we studied the aromatization of a series of 6alpha- and 6beta-alkyl (methyl, ethyl, n-propyl, n-pentyl and n-heptyl)-substituted androst-4-ene-3,17-diones (ADs) and their androsta-1,4-diene-3,17-dione (ADD) derivatives with human placental aromatase, by gas chromatography-mass spectrometry. Among the inhibitors examined, ADD and its 6alpha-alkyl derivatives with alkyl functions less than three carbons long, together with 6beta-methyl ADD, are suicide substrates of aromatase. All of the steroids, except for 6beta-n-pentyl ADD and its n-heptyl analogue as well as 6beta-n-heptyl AD, were found to be converted into the corresponding 6-alkyl oestrogens. The 6-methyl steroids were aromatized most efficiently in each series, and the aromatization rate essentially decreased in proportion to the length of the 6-alkyl chains in each series, where the 6alpha-alkyl androgens were more efficient substrates than the corresponding 6beta isomers. The Vmax of 6alpha-methyl ADD was approx. 2.5-fold that of the natural substrate AD and approx. 3-fold that of the parent ADD. On the basis of this, along with the facts that the rates of a mechanism-based inactivation of aromatase by ADD and its 6alpha-methyl derivative are similar, it is implied that alignment of 6alpha-methyl ADD in the active site could favour the pathway leading to oestrogen over the inactivation pathway, compared with that of ADD. The relative apparent Km values for the androgens obtained in this study are different from the relative Ki values obtained previously, indicating that there is a difference between the ability to serve as an inhibitor and the ability to serve as a substrate in the 6-alkyl androgen series. PMID:9405288
The relation of plasma androgen levels to sexual behaviors and attitudes of women.
Persky, H; Dreisbach, L; Miller, W R; O'Brien, C P; Khan, M A; Lief, H I; Charney, N; Strauss, D
1982-09-01
Four androgens: dehydroepiandrosterone (DHEA), androstenedione (A), testosterone (T), and dihydrotestosterone (DHT), a variety of sexual behaviors and attitudes, and several moods were determined regularly in two groups of healthy, married women who differed by three decades in age. The younger women exhibited significantly higher levels of each androgen, the differences being almost entirely attributable to ovarian failure in the older group. Although the older women reported the same levels of sexual desire and sexual arousal as the younger women, their intercourse frequencies and self-rated sexual gratification scores were significantly lower than the values obtained for the younger wives. One or more of the androgen levels related significantly and in the expected direction to each stage of the four-stage sexual response process. Global measures of so-called "sexual adjustment" and estimates of anxiety, depression, and hostility feelings experienced by these women did not relate significantly to any of the four androgen levels.
MicroRNAs Are Mediators of Androgen Action in Prostate and Muscle
Narayanan, Ramesh; Jiang, Jinmai; Gusev, Yuriy; Jones, Amanda; Kearbey, Jeffrey D.; Miller, Duane D.; Schmittgen, Thomas D.; Dalton, James T.
2010-01-01
Androgen receptor (AR) function is critical for the development of male reproductive organs, muscle, bone and other tissues. Functionally impaired AR results in androgen insensitivity syndrome (AIS). The interaction between AR and microRNA (miR) signaling pathways was examined to understand the role of miRs in AR function. Reduction of androgen levels in Sprague-Dawley rats by castration inhibited the expression of a large set of miRs in prostate and muscle, which was reversed by treatment of castrated rats with 3 mg/day dihydrotestosterone (DHT) or selective androgen receptor modulators. Knockout of the miR processing enzyme, DICER, in LNCaP prostate cancer cells or tissue specifically in mice inhibited AR function leading to AIS. Since the only function of miRs is to bind to 3′ UTR and inhibit translation of target genes, androgens might induce miRs to inhibit repressors of AR function. In concordance, knock-down of DICER in LNCaP cells and in tissues in mice induced the expression of corepressors, NCoR and SMRT. These studies demonstrate a feedback loop between miRs, corepressors and AR and the imperative role of miRs in AR function in non-cancerous androgen-responsive tissues. PMID:21048966
Simultaneous ultramicroanalysis of both 17-keto-and 17beta-hydroxy androgens in biological fluids.
Ganjam, V K
1976-11-01
Sensitive methods for quantifying androgens were lacking. Therefore, a relatively simple procedure for separating steroids was combined with highly specific assay methods so that eight androgens could be measured with high accuracy, precision and sensitivity. Semi-automated separations on Sephadex LH-20 columns used heptane:methylene chloride:ethanol:water (50:50:1:0.12) and a flow rate of 17.0 min/ml. The six peaks eluted contained androstenedine; androsterone, epiandrosterone and dihydrotestosterone; testosterone and dehydroepiandrosterone; 3alpha-androstanediol; 3beta-androstanediol; and androstenediol. Androstenedione, dehydroepiandrosterone and androstenediol were quantified using specific antisera (sensitivity less than or equal to 75 pg). Testosterone and dihydrotestosterone were measured by competitive protein-binding assays using rabbit TeBG (sensitivity less than or equal to 150 pg). 3alpha- and 3beta-androstanediol were similarly assayed using human TeBG (sensitivity approximately 150 pg). Androsterone was reduced with NaBH4 and the resulting 3alpha-androstanediol was assayed using human TeBG (sensitivity approximately 200 pg). Inter- and intra-assay variations were less than 10% for radioimmunoassays and less than 16% for competitive protein-binding assays over the entire dose response curve.
Recent Advances in Drug Design and Drug Discovery for Androgen-Dependent Diseases
Cabeza, Marisa; Sánchez-Márquez, Araceli; Garrido, Mariana; Silva, Aylín; Bratoeff, Eugene
2016-01-01
This article summarizes the importance of different targets such as 5α-reductase, 17β-HSD, CYP17A, androgen receptor and protein kinase A for the treatment of prostate cancer and benign prostatic hyperplasia. It is a well known fact that dihydrotestosterone (DHT) is associated with the development of androgen-dependent afflictions. At the present time, several research groups are attempting to develop new steroidal and non-steroidal molecules with the purpose of inhibiting the synthesis and biological response of DHT. This review also discusses the most recent studies reported in the literature that describe the therapeutic potential of novel compounds, as well as the new drugs, principally inhibitors of 5α-reductase. PMID:26861003
Recent Advances in Drug Design and Drug Discovery for Androgen- Dependent Diseases.
Cabeza, Marisa; Sánchez-Márquez, Araceli; Garrido, Mariana; Silva, Aylín; Bratoeff, Eugene
2016-01-01
This article summarizes the importance of different targets such as 5α-reductase, 17β-HSD, CYP17A, androgen receptor and protein kinase A for the treatment of prostate cancer and benign prostatic hyperplasia. It is a well known fact that dihydrotestosterone (DHT) is associated with the development of androgen-dependent afflictions. At the present time, several research groups are attempting to develop new steroidal and non-steroidal molecules with the purpose of inhibiting the synthesis and biological response of DHT. This review also discusses the most recent studies reported in the literature that describe the therapeutic potential of novel compounds, as well as the new drugs, principally inhibitors of 5α-reductase.
Orr, Christopher R.; Montie, Heather L.; Liu, Yuhong; Bolzoni, Elena; Jenkins, Shannon C.; Wilson, Elizabeth M.; Joseph, James D.; McDonnell, Donald P.; Merry, Diane E.
2010-01-01
Polyglutamine expansion within the androgen receptor (AR) causes spinal and bulbar muscular atrophy (SBMA) and is associated with misfolded and aggregated species of the mutant AR. We showed previously that nuclear localization of the mutant AR was necessary but not sufficient for SBMA. Here we show that an interdomain interaction of the AR that is central to its function within the nucleus is required for AR aggregation and toxicity. Ligands that prevent the interaction between the amino-terminal FXXLF motif and carboxyl-terminal AF-2 domain (N/C interaction) prevented toxicity and AR aggregation in an SBMA cell model and rescued primary SBMA motor neurons from 5α-dihydrotestosterone-induced toxicity. Moreover, genetic mutation of the FXXLF motif prevented AR aggregation and 5α-dihydrotestosterone toxicity. Finally, selective androgen receptor modulators, which prevent the N/C interaction, ameliorated AR aggregation and toxicity while maintaining AR function, highlighting a novel therapeutic strategy to prevent the SBMA phenotype while retaining AR transcriptional function. PMID:20826791
Unwalla, Ray; Mousseau, James J; Fadeyi, Olugbeminiyi O; Choi, Chulho; Parris, Kevin; Hu, Baihua; Kenney, Thomas; Chippari, Susan; McNally, Christopher; Vishwanathan, Karthick; Kilbourne, Edward; Thompson, Catherine; Nagpal, Sunil; Wrobel, Jay; Yudt, Matthew; Morris, Carl A; Powell, Dennis; Gilbert, Adam M; Chekler, Eugene L Piatnitski
2017-07-27
In an effort to find new and safer treatments for osteoporosis and frailty, we describe a novel series of selective androgen receptor modulators (SARMs). Using a structure-based approach, we identified compound 7, a potent AR (ARE EC 50 = 0.34 nM) and selective (N/C interaction EC 50 = 1206 nM) modulator. In vivo data, an AR LBD X-ray structure of 7, and further insights from modeling studies of ligand receptor interactions are also presented.
Androgen and AR contribute to breast cancer development and metastasis: an insight of mechanisms.
Feng, J; Li, L; Zhang, N; Liu, J; Zhang, L; Gao, H; Wang, G; Li, Y; Zhang, Y; Li, X; Liu, D; Lu, J; Huang, B
2017-05-18
The role of androgen and androgen receptor (AR) in breast carcinogenesis has long been a disputed issue. This report provides a mechanistic insight into how androgen and AR contributes to invasion and metastasis of breast cancer. We find that dihydrotestosterone (DHT) is able to induce the epithelial-to-mesenchymal transition in breast cancer cells in an AR-dependent/estrogen receptor-independent manner. This process is dependent on the demethylation activity of lysine-specific demethylase 1A (LSD1) by epigenetically regulating the target genes E-cadherin and vimentin. In vivo, DHT promotes metastasis in a nude mouse model, and AR and LSD1 are indispensable in this process. We establish that higher expression of nucleus AR to cytoplasm AR associated with worse prognostic outcomes in breast cancer patient samples. This study maps an 'androgen-AR/LSD1-target genes' pathway in breast carcinogenesis, implicating the importance of hormonal balance in women, and the potential clinical significance of serum androgen and AR in prediction of breast cancer and selection of breast cancer therapy.
Early embryonic androgen exposure induces transgenerational epigenetic and metabolic changes.
Xu, Ning; Chua, Angela K; Jiang, Hong; Liu, Ning-Ai; Goodarzi, Mark O
2014-08-01
Androgen excess is a central feature of polycystic ovary syndrome (PCOS), which affects 6% to 10% of young women. Mammals exposed to elevated androgens in utero develop PCOS-like phenotypes in adulthood, suggesting fetal origins of PCOS. We hypothesize that excess androgen exposure during early embryonic development may disturb the epigenome and disrupt metabolism in exposed and unexposed subsequent generations. Zebrafish were used to study the underlying mechanism of fetal origins. Embryos were exposed to androgens (testosterone and dihydrotestosterone) early at 26 to 56 hours post fertilization or late at 21 to 28 days post fertilization. Exposed zebrafish (F0) were grown to adults and crossed to generate unexposed offspring (F1). For both generations, global DNA methylation levels were examined in ovaries using a luminometric methylation assay, and fasting and postprandial blood glucose levels were measured. We found that early but not late androgen exposure induced changes in global methylation and glucose homeostasis in both generations. In general, F0 adult zebrafish exhibited altered global methylation levels in the ovary; F1 zebrafish had global hypomethylation. Fasting blood glucose levels were decreased in F0 but increased in F1; postprandial glucose levels were elevated in both F0 and F1. This androgenized zebrafish study suggests that transient excess androgen exposure during early development can result in transgenerational alterations in the ovarian epigenome and glucose homeostasis. Current data cannot establish a causal relationship between epigenetic changes and altered glucose homeostasis. Whether transgenerational epigenetic alteration induced by prenatal androgen exposure plays a role in the development of PCOS in humans deserves study.
Artificial masculinization in tilapia involves androgen receptor activation.
Golan, Matan; Levavi-Sivan, Berta
2014-10-01
Estrogens have a pivotal role in natural female sexual differentiation of tilapia while lack of steroids results in testicular development. Despite the fact that androgens do not participate in natural sex differentiation, synthetic androgens, mainly 17-α-methyltestosterone (MT) are effective in the production of all-male fish in aquaculture. The sex inversion potency of synthetic androgens may arise from their androgenic activity or else as inhibitors of aromatase activity. The current study is an attempt to differentiate between the two alleged activities in order to evaluate their contribution to the sex inversion process and aid the search for novel sex inversion agents. In the present study, MT inhibited aromatase activity, when applied in vitro as did the non-aromatizable androgen dihydrotestosterone (DHT). In comparison, exposure to fadrozole, a specific aromatase inhibitor, was considerably more effective. Androgenic activity of MT was evaluated by exposure of Sciaenochromis fryeri fry to the substance and testing for the appearance of blue color. Flutamide, an androgen antagonist, administered concomitantly with MT, reduced the appearance of the blue color and the sex inversion potency of MT in a dose-dependent manner. In tilapia, administration of MT, fadrozole or DHT resulted in efficient sex inversion while flutamide reduced the sex inversion potency of all three compounds. In the case of MT and DHT the decrease in sex inversion efficiency caused by flutamide is most likely due to the direct blocking of the androgen binding to its cognate receptor. The negative effect of flutamide on the efficiency of the fadrozole treatment may indicate that the masculinizing activity of fadrozole may be attributed to excess, un-aromatized, androgens accumulated in the differentiating gonad. The present study shows that when androgen receptors are blocked, there is a reduction in the efficiency of sex inversion treatments. Our results suggest that in contrast to
Finasteride Treatment Alters Tissue Specific Androgen Receptor Expression in Prostate Tissues
Bauman, Tyler M.; Sehgal, Priyanka D.; Johnson, Karen A.; Pier, Thomas; Bruskewitz, Reginald C.; Ricke, William A.; Huang, Wei
2014-01-01
BACKGROUND Normal and pathologic growth of the prostate is dependent on the synthesis of dihydrotestosterone (DHT) from testosterone by 5α-reductase. Finasteride is a selective inhibitor of 5α-reductase 2, one isozyme of 5α-reductase found in abundance in the human prostate. The objective of this study was to investigate the effects of finasteride on androgen receptor expression and tissue morphology in human benign prostatic hyperplasia specimens. METHODS Patients undergoing transurethral resection of the prostate and either treated or not treated with finasteride between 2004 and 2010 at the University of Wisconsin-Hospital were retrospectively identified using an institutional database. Prostate specimens from each patient were triple-stained for androgen receptor, prostate-specific antigen, and basal marker cytokeratin 5. Morphometric analysis was performed using the multispectral imaging, and results were compared between groups of finasteride treated and non-treated patients. RESULTS Epithelial androgen receptor but not stromal androgen receptor expression was significantly lower in patients treated with finasteride than in non-treated patients. Androgen receptor-regulated prostate-specific antigen was not significantly decreased in finasteride-treated patients. Significant luminal epithelial atrophy and basal cell hyperplasia were prevalent in finasteride treated patients. Epithelial androgen receptor expression was highly correlated to the level of luminal epithelial atrophy. CONCLUSIONS In this study, finasteride decreased the expression of epithelial androgen receptor in a tissue specific manner. The correlation between epithelial androgen receptor and the extent of luminal epithelial atrophy suggests that epithelial androgen receptor may be directly regulating the atrophic effects observed with finasteride treatment. PMID:24789081
Synergistic activation of the androgen receptor by bombesin and low-dose androgen.
Dai, Jie; Shen, Ruoqian; Sumitomo, Makoto; Stahl, Rosalyn; Navarro, Daniel; Gershengorn, Marvin C; Nanus, David M
2002-07-01
Neuropeptide growth factors such as bombesinare implicated in progression to androgen-independent prostate cancer (PC). We examined the impact of bombesin on androgen receptor (AR)-mediated gene expression. The AR together with the AR-responsive probasin ARR(3)tk-luc or PSA-pPUE-ELB-luc promoter was cotransfected into Swiss 3T3 and PC-3 cells, both of which express high-affinity bombesin receptors; the cells were incubated with bombesin (0-50 nM) and dihydrotestosterone (DHT; 0-10 nM), and luciferase activities were measured. DHT increased transcription approximately 40-fold at doses of 1 and 10 nM but had no effect at 10 pM. Bombesin alone, or with 1 or 10 nM DHT, did not further increase transcription. However, 5 nM bombesin and 10 pM DHT, doses that by themselves had no effect, resulted in a approximately 20 fold increase in transcription (P < 0.005). This synergistic effect was blocked by bombesin receptor antagonists and recombinant neutral endopeptidase, which hydrolyzes bombesin. Bombesin and DHT together also increased binding of nuclear extracts from PC-3 cells transfected with AR to a consensus androgen response element in mobility shift assays and increased the level of secreted prostate-specific antigen in LNCaP cell supernatant compared with DHT or bombesin alone. Immunoprecipitation of AR from (32)P-labeled LNCaP cells revealed that 5 nM bombesin + 10 pM DHT induced AR phosphorylation comparable with 1 nM DHT, whereas bombesin or 10 pM DHT alone did not. These data indicate that bombesin can synergize with low (castrate) levels of DHT to induce AR-mediated transcription and suggest that neuropeptides promote AR-mediated signaling in androgen-independent prostate cancer.
Zhao, Juan; Harada, Naoaki; Okajima, Kenji
2011-10-01
We demonstrated that insulin-like growth factor-I (IGF-I) production in dermal papillae was increased and hair growth was promoted after sensory neuron stimulation in mice. Although the androgen metabolite dihydrotestosterone (DHT) inhibits hair growth by negatively modulating growth-regulatory effects of dermal papillae, relationship between androgen metabolism and IGF-I production in dermal papillae is not fully understood. We examined whether DHT inhibits IGF-I production by inhibiting sensory neuron stimulation, thereby preventing hair growth in mice. Effect of DHT on sensory neuron stimulation was examined using cultured dorsal root ganglion (DRG) neurons isolated from mice. DHT inhibits calcitonin gene-related peptide (CGRP) release from cultured DRG neurons. The non-steroidal androgen-receptor antagonist flutamide reversed DHT-induced inhibition of CGRP release. Dermal levels of IGF-I and IGF-I mRNA, and the number of IGF-I-positive fibroblasts around hair follicles were increased at 6h after CGRP administration. DHT administration for 3weeks decreased dermal levels of CGRP, IGF-I, and IGF-I mRNA in mice. Immunohistochemical expression of IGF-I and the number of proliferating cells in hair follicles were decreased and hair re-growth was inhibited in animals administered DHT. Co-administration of flutamide and CGRP reversed these changes induced by DHT administration. These observations suggest that DHT may decrease IGF-I production in dermal papillae by inhibiting sensory neuron stimulation through interaction with the androgen receptor, thereby inhibiting hair growth in mice. Copyright © 2011 Elsevier Ltd. All rights reserved.
Early Embryonic Androgen Exposure Induces Transgenerational Epigenetic and Metabolic Changes
Xu, Ning; Chua, Angela K.; Jiang, Hong; Liu, Ning-Ai
2014-01-01
Androgen excess is a central feature of polycystic ovary syndrome (PCOS), which affects 6% to 10% of young women. Mammals exposed to elevated androgens in utero develop PCOS-like phenotypes in adulthood, suggesting fetal origins of PCOS. We hypothesize that excess androgen exposure during early embryonic development may disturb the epigenome and disrupt metabolism in exposed and unexposed subsequent generations. Zebrafish were used to study the underlying mechanism of fetal origins. Embryos were exposed to androgens (testosterone and dihydrotestosterone) early at 26 to 56 hours post fertilization or late at 21 to 28 days post fertilization. Exposed zebrafish (F0) were grown to adults and crossed to generate unexposed offspring (F1). For both generations, global DNA methylation levels were examined in ovaries using a luminometric methylation assay, and fasting and postprandial blood glucose levels were measured. We found that early but not late androgen exposure induced changes in global methylation and glucose homeostasis in both generations. In general, F0 adult zebrafish exhibited altered global methylation levels in the ovary; F1 zebrafish had global hypomethylation. Fasting blood glucose levels were decreased in F0 but increased in F1; postprandial glucose levels were elevated in both F0 and F1. This androgenized zebrafish study suggests that transient excess androgen exposure during early development can result in transgenerational alterations in the ovarian epigenome and glucose homeostasis. Current data cannot establish a causal relationship between epigenetic changes and altered glucose homeostasis. Whether transgenerational epigenetic alteration induced by prenatal androgen exposure plays a role in the development of PCOS in humans deserves study. PMID:24992182
Audet-Walsh, Étienne; Yee, Tracey; Tam, Ingrid S; Giguère, Vincent
2017-04-01
5α-Reductase types 1 and 2, encoded by SRD5A1 and SRD5A2, are the two enzymes that can catalyze the conversion of testosterone to dihydrotestosterone, the most potent androgen receptor (AR) agonist in prostate cells. 5α-Reductase type 2 is the predominant isoform expressed in the normal prostate. However, its expression decreases during prostate cancer (PCa) progression, whereas SRD5A1 increases, and the mechanism underlying this transcriptional regulatory switch is still unknown. Interrogation of SRD5A messenger RNA expression in three publicly available data sets confirmed that SRD5A1 is increased in primary and metastatic PCa compared with nontumoral prostate tissues, whereas SRD5A2 is decreased. Activation of AR, a major oncogenic driver of PCa, induced the expression of SRD5A1 from twofold to fourfold in three androgen-responsive PCa cell lines. In contrast, AR repressed SRD5A2 expression in this context. Chromatin-immunoprecipitation studies established that AR is recruited to both SRD5A1 and SRD5A2 genes following androgen stimulation but initiates transcriptional activation only at SRD5A1 as monitored by recruitment of RNA polymerase II and the presence of the H3K27Ac histone mark. Furthermore, we showed that the antiandrogens bicalutamide and enzalutamide block the AR-mediated regulation of both SRD5A1 and SRD5A2, highlighting an additional mechanism explaining their beneficial effects in patients. In summary, we identified an AR-dependent transcriptional regulation that explains the differential expression of 5α-reductase types 1 and 2 during PCa progression. Our work thus defines a mechanism by which androgens control their own synthesis via differential regulatory control of the expression of SRD5A1 and SRD5A2. Copyright © 2017 Endocrine Society.
Mulholland, David J; Cox, Michael; Read, Jason; Rennie, Paul; Nelson, Colleen
2004-05-01
Renilla based reporters are frequently used as transfection controls for luciferase transcriptional reporter assays. However, recent evidence suggests that a commonly used reporter (HSV-thymidine kinase driven Renilla) is responsive to androgen receptor (AR) and glucocorticoid receptors in the presence of the cognate ligands, dihydrotestosterone (DHT) and dexamethasone (DEX), respectively [1]. We further validate this important technical difficulty by illustrating that in LNCaP prostate cancer cells, spurious Renilla luciferase activity is a function of (a) the promoter driving Renilla expression, (b) the presence of co-transfected transgenes, and (c) the androgen responsiveness of the cell line used. Using inhibitors of transcription and translation we showed that transcript interference or translational modulation is not a major means by which androgens affect Renilla luciferase activity. As luciferase reporter assays are a frequent means of studying transcriptional co-regulation in the highly androgen dependent LNCaP cell line, our data serves as a cautionary note that alternative normalization techniques should be employed to avoid misinterpretation of data. Copyright 2004 Wiley-Liss, Inc.
Application of protein expression profiling to screen chemicals for androgenic activity.
Hemmer, Michael J; Salinas, Kimberly A; Harris, Peggy S
2011-05-01
Protein expression changes can be used for detection of biomarkers that can be applied diagnostically to screen chemicals for endocrine modifying activity. In this study, surface enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS) coupled with a short term fish assay was used to investigate changes in plasma protein expression as a means to screen chemicals for androgenic activity. Adult gravid female sheepshead minnows (Cyprinodon variegatus) were placed into separate aquaria for seawater control, ethanol solvent control, and the following androgen agonist treatments at 5.0μg/L: dihydrotestosterone (DHT), methyldihydrotestosterone (MDHT), testosterone (T), methyltestosterone (MT) and trenbolone (TB). Treatments of 0.6μg/L endosulfan and 40μg/L chlorpyrifos (CP) served as non-androgenic negative stressor controls. Test concentrations were maintained using an intermittent flow-through dosing apparatus supplying exposure water at 20L/h. Fish were sampled at 7 days, the plasma diluted, processed on weak cation exchange CM10 ProteinChip arrays and analyzed. Spectral processing resulted in 249 individual m/z peak clusters for the androgen exposed fish. Partial least squares-discriminant analysis was used to develop an androgen-responsive model using sample spectra from exposures with DHT and unexposed solvent control fish as the training set. The androgen classification model performed with ≥79% specificity (% true negative) and ≥70% sensitivity (% true positive) for non-aromatizable androgens. The aromatizable androgens T and MT were classified as androgenic with specificities of 42 and 79%, respectively. The reduction in sensitivity observed with T is thought to be caused by its metabolic conversion to an estrogen by aromatase. The results of these studies show diagnostic plasma protein expression models can correctly classify chemicals by their androgenic activity using a combination of high throughput mass spectrometry and
DOE Office of Scientific and Technical Information (OSTI.GOV)
Morooka, Nobukatsu, E-mail: amorooka@gunma-u.ac.jp; Ueguri, Kei; Yee, Karen Kar Lye
Age-related decreases in sex hormones are closely related to chronic inflammation in obesity and metabolic diseases. Particularly, the molecular basis of androgen activity in regulating inflammation and controlling metabolism remains largely unknown. Obese adipocytes secrete monocyte chemoattractant protein-1 (MCP-1), a key chemokine that promotes the infiltration of monocytes/macrophages into adipose tissue, thereby leading to metabolic disorders. Here, we studied the role of androgen-androgen receptor (AR) action in regulating MCP-1 expression in adipose tissue. We observed the induction of Mcp-1 expression in 3T3-L1 adipocytes co-cultured with RAW264.7 macrophages. Additionally, Mcp-1 expression was upregulated by culturing in conditioned medium derived from inflammatorymore » macrophages (M1-Mφ) containing tumor necrosis factor-alpha (TNF-α). We found that sex hormones downregulated TNF-α-induced Mcp-1 and interleukin (Il)-6 expression in 3T3-L1 adipocytes. Furthermore, luciferase-reporter analysis indicated that MCP-1 promoter activity was predominantly suppressed by dihydrotestosterone (DHT)-AR interactions through functional canonical nuclear factor-kappa B (NF-κB) sites, whereas non-canonical NF-κB site containing important flanking sequences exhibited minor contributions to DHT-AR transcriptional repression. These findings suggested that androgen-AR suppressed obesity-induced chronic inflammation in adipose tissue. - Highlights: • DHT, non-aromatizable androgen suppresses Mcp-1 expression in adipocytes. • Mcp-1 transcription was negatively regulated by DHT-AR action. • DHT-AR selectively regulates Mcp-1 transcription through distinct NF-κB sites.« less
Kumagai, Jinpei; Hofland, Johannes; Erkens-Schulze, Sigrun; Dits, Natasja F J; Steenbergen, Jacobie; Jenster, Guido; Homma, Yukio; de Jong, Frank H; van Weerden, Wytske M
2013-11-01
Despite an initial response to hormonal therapy, patients with advanced prostate cancer (PC) almost always progress to castration-resistant disease (CRPC). Although serum testosterone (T) is reduced by androgen deprivation therapy, intratumoral T levels in CRPC are comparable to those in prostate tissue of eugonadal men. These levels could originate from intratumoral conversion of adrenal androgens and/or from de novo steroid synthesis. However, the relative contribution of de novo steroidogenesis to AR-driven cell growth is unknown. The relative contribution of androgen biosynthetic pathways to activate androgen receptor (AR)-regulated cell growth and expression of PSA, FKBP5, and TMPRSS2 was studied at physiologically relevant levels of adrenal androgen precursors and intermediates of de novo androgen biosynthesis in human prostate cancer cell lines, PC346C, VCaP, and LNCaP. In PC346C and VCaP, responses to pregnenolone and progesterone were absent or minimal, while large effects of adrenal androgen precursors were found. VCaP CRPC clones overexpressing CYP17A1 did not acquire an increased ability to use pregnenolone or progesterone to activate AR. In contrast, all precursors stimulated growth and gene expression in LNCaP cells, presumably resulting from the mutated AR in these cells. Our data indicate that at physiological levels of T precursors PC cells can generally convert adrenal androgens, while de novo steroidogenesis is not generally possible in PC cells and is not able to support AR transactivation and PC growth. © 2013 Wiley Periodicals, Inc.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kakoki, Katsura; Department of AIDS Research, Institute of Tropical Medicine, G-COE, Nagasaki University, Nagasaki 852-8523; Department of Urology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8523
Highlights: • XMRV infection induces androgen-independent growth in LNCaP cells. • XMRV infection reduces expression of androgen receptor. • XMRV promotes appearance of androgen blocker-resistant prostate cancer cells. - Abstract: Xenotropic murine leukemia virus-related virus (XMRV) is a novel gammaretrovirus that was originally isolated from human prostate cancer. It is now believed that XMRV is not the etiologic agent of prostate cancer. An analysis of murine leukemia virus (MLV) infection in various human cell lines revealed that prostate cancer cell lines are preferentially infected by XMRV, and this suggested that XMRV infection may confer some sort of growth advantage tomore » prostate cancer cell lines. To examine this hypothesis, androgen-dependent LNCaP cells were infected with XMRV and tested for changes in certain cell growth properties. We found that XMRV-infected LNCaP cells can proliferate in the absence of the androgen dihydrotestosterone. Moreover, androgen receptor expression is significantly reduced in XMRV-infected LNCaP cells. Such alterations were not observed in uninfected and amphotropic MLV-infected LNCaP cells. This finding explains why prostate cancer cell lines are preferentially infected with XMRV.« less
Concept and viability of androgen annihilation for advanced prostate cancer.
Mohler, James L
2014-09-01
There remains no standard of care for patients with a rising prostate-specific antigen level after radical prostatectomy or radiotherapy but who have no radiographic metastases, even though this is the second largest group of patients with prostate cancer (CaP) in the United States. Androgen deprivation therapy (ADT) may cure some men with advanced CaP based on single-institution series and a randomized clinical trial of immediate versus delayed ADT for men found to have pelvic lymph node metastasis at the time of radical prostatectomy. ADT may be more effective when initiated for minimal disease burden, which can be detected using PSA after radical prostatectomy or radiotherapy, and if more complete disruption of the androgen axis using newer agents decreases the chance that androgen-sensitive cells survive to adapt to a low-androgen environment. Androgens may be "annihilated" simultaneously using a luteinizing hormone-releasing hormone antagonist or agonist to inhibit testicular production of testosterone, a P45017A1 (CYP17A1) inhibitor to diminish metabolism of testosterone via the adrenal pathway and dihydrotestosterone (DHT) via the backdoor pathway, a 5α-reductase (SRD5A) inhibitor to diminish testosterone reduction to DHT and backdoor metabolism of progesterone substrates to DHT, and a newer antiandrogen to compete better with DHT for the androgen receptor ligand-binding domain. Early initiation of androgen annihilation for induction as part of planned intermittent ADT should be safe, may reduce tumor burden below a threshold that allows eradication by the immune system, and may cure many men who have failed definitive local therapy. © 2014 American Cancer Society.
Bobach, Claudia; Tennstedt, Stephanie; Palberg, Kristin; Denkert, Annika; Brandt, Wolfgang; de Meijere, Armin; Seliger, Barbara; Wessjohann, Ludger A
2015-01-27
The androgen receptor is an important pharmaceutical target for a variety of diseases. This paper presents an in silico/in vitro screening procedure to identify new androgen receptor ligands. The two-step virtual screening procedure uses a three-dimensional pharmacophore model and a docking/scoring routine. About 39,000 filtered compounds were docked with PLANTS and scored by Chemplp. Subsequent to virtual screening, 94 compounds, including 28 steroidal and 66 nonsteroidal compounds, were tested by an androgen receptor fluorescence polarization ligand displacement assay. As a result, 30 compounds were identified that show a relative binding affinity of more than 50% in comparison to 100 nM dihydrotestosterone and were classified as androgen receptor binders. For 11 androgen receptor binders of interest IC50 and Ki values were determined. The compound with the highest affinity exhibits a Ki value of 10.8 nM. Subsequent testing of the 11 compounds in a PC-3 and LNCaP multi readout proliferation assay provides insights into the potential mode of action. Further steroid receptor ligand displacement assays and docking studies on estrogen receptors α and β, glucocorticoid receptor, and progesterone receptor gave information about the specificity of the 11 most active compounds. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Schwabl, H.; Palacios, M.G.; Martin, T.E.
2007-01-01
Greater offspring predation favors evolution of faster development among species. We hypothesized that greater offspring predation exerts selection on mothers to increase levels of anabolic androgens in egg yolks to achieve faster development. Here, we tested whether (1) concentrations of yolk androgens in passerine species were associated with offspring predation and (2) embryo and nestling development rates were associated with yolk androgen concentrations. We examined three androgens that increase in potency along the synthesis pathway: androstenedione (A4) to testosterone (T) to 5??- dihydrotestosterone (5??-DHT). Concentrations of none of these steroids were related to clutch size; only A4 was allometrically related to egg volume. Species that experience greater predation showed higher yolk concentrations of T and 5??-DHT. Higher concentrations of T and particularly 5??-DHT were strongly correlated with faster development during the embryo period and less so during the nestling period. Development rates were most strongly correlated with 5??-DHT, suggesting that potency increases along the androgen synthesis pathway and that effects are mediated by the androgen receptor pathway. These results are consistent with the hypothesis that selection for faster development by time-dependent offspring mortality may be achieved epigenetically by varying embryo exposure to maternal anabolic steroids. ?? 2007 by The University of Chicago. All rights reserved.
Li, Jin; Ding, Zhiyong; Wang, Zhengxin; Lu, Jing-Fang; Maity, Sankar N.; Navone, Nora M.; Logothetis, Christopher J.; Mills, Gordon B.; Kim, Jeri
2011-01-01
The enzyme 5α-reductase, which converts testosterone to dihydrotestosterone (DHT), performs key functions in the androgen receptor (AR) signaling pathway. The three isoenzymes of 5α-reductase identified to date are encoded by different genes: SRD5A1, SRD5A2, and SRD5A3. In this study, we investigated mechanisms underlying androgen regulation of 5α-reductase isoenzyme expression in human prostate cells. We found that androgen regulates the mRNA level of 5α-reductase isoenzymes in a cell type–specific manner, that such regulation occurs at the transcriptional level, and that AR is necessary for this regulation. In addition, our results suggest that AR is recruited to a negative androgen response element (nARE) on the promoter of SRD5A3 in vivo and directly binds to the nARE in vitro. The different expression levels of 5α-reductase isoenzymes may confer response or resistance to 5α-reductase inhibitors and thus may have importance in prostate cancer prevention. PMID:22194926
Pharmacodynamics of selective androgen receptor modulators.
Yin, Donghua; Gao, Wenqing; Kearbey, Jeffrey D; Xu, Huiping; Chung, Kiwon; He, Yali; Marhefka, Craig A; Veverka, Karen A; Miller, Duane D; Dalton, James T
2003-03-01
The present study aimed to identify selective androgen receptor modulators (SARMs) with in vivo pharmacological activity. We examined the in vitro and in vivo pharmacological activity of four chiral, nonsteroidal SARMs synthesized in our laboratories. In the in vitro assays, these compounds demonstrated moderate to high androgen receptor (AR) binding affinity, with K(i) values ranging from 4 to 37 nM, and three of the compounds efficaciously stimulated AR-mediated reporter gene expression. The compounds were then administered subcutaneously to castrated rats to appraise their in vivo pharmacological activity. Androgenic activity was evaluated by the ability of these compounds to maintain the weights of prostate and seminal vesicle, whereas levator ani muscle weight was used as a measure of anabolic activity. The maximal response (E(max)) and dose for half-maximal effect (ED(50)) were determined for each compound and compared with that observed for testosterone propionate (TP). Compounds S-1 and S-4 demonstrated in vivo androgenic and anabolic activity, whereas compounds S-2 and S-3 did not. The activities of S-1 and S-4 were tissue-selective in that both compounds stimulated the anabolic organs more than the androgenic organs. These two compounds were less potent and efficacious than TP in androgenic activity, but their anabolic activity was similar to or greater than that of TP. Neither S-1 nor S-4 caused significant luteinizing hormone or follicle stimulating hormone suppression at doses near the ED(50) value. Thus, compounds S-1 and S-4 were identified as SARMs with potent and tissue-selective in vivo pharmacological activity, and represent the first members of a new class of SARMs with selective anabolic effects.
Tributyltin distribution and producing androgenic activity in water, sediment, and fish muscle.
Shue, Meei-Fang; Chen, Ting-Chien; Bellotindos, Luzvisminda M; Lu, Ming-Chun
2014-01-01
This study investigated the concentrations of Tributyltin (TBT) in water, sediment, and fish muscle samples taken from Kaohsiung Harbor and Kaoping River estuary, Taiwan. TBT concentrations in water and sediment samples ranged from less than 18.5 to 34.1 ng Sn L(-1) and from 2.44 to 29.7 ng Sn g(-1) weight per weight (w/w), respectively. Concentrations in the TBT-contaminated fish muscle samples ranged from 10.8 to 79.6 ng Sn g(-1) w/w. The TBT concentrations in fish muscle were higher than those in water and sediment samples. The fish muscle/water TBT bioconcentration factor (BCF) ranged from 590 to 3363 L kg(-1). Additionally, the water samples were assessed for androgenic activity with an MCF7-AR1 human breast cancer cell line. The androgenic activity ranged from 0.94 to 3.1 ng-dihydrotestosterone per litre water (ng-DHT L(-1)). Higher concentrations of TBT in water and sediment samples occurred in the dry season, but the androgenic activity had higher values in the rainy season.
Marhefka, Craig A; Gao, Wenqing; Chung, Kiwon; Kim, Juhyun; He, Yali; Yin, Donghua; Bohl, Casey; Dalton, James T; Miller, Duane D
2004-02-12
A series of nonsteroidal ligands were synthesized as second-generation agonists for the androgen receptor (AR). These ligands were designed to eliminate metabolic sites identified in one of our first-generation AR agonists, which was inactive in vivo due to its rapid metabolism to inactive constituents. The binding affinity of these compounds was evaluated using AR isolated from rat ventral prostate. These second-generation compounds bound the AR in a high affinity and stereoselective manner, with K(i) values ranging from about 4 to 130 nM. The ability of these ligands to stimulate AR-mediated transcriptional activation was examined in cells transfected with the human AR and a hormone-dependent luciferase reporter gene. Although some compounds were unable to stimulate AR-mediated transcription, several demonstrated activity similar to that of dihydrotestosterone (DHT, an endogenous steroidal ligand for the AR). We also evaluated the in vivo pharmacologic activity of selected compounds in castrated male rats. Three compounds were identified as selective androgen receptor modulators (SARMs), exhibiting significant anabolic activity while having only moderate to minimal androgenic activity in vivo.
Marhefka, Craig A.; Gao, Wenqing; Chung, Kiwon; Kim, Juhyun; He, Yali; Yin, Donghua; Bohl, Casey; Dalton, James T.; Miller, Duane D.
2007-01-01
A series of nonsteroidal ligands were synthesized as second-generation agonists for the androgen receptor (AR). These ligands were designed to eliminate metabolic sites identified in one of our first-generation AR agonists, which was inactive in vivo due to its rapid metabolism to inactive constituents. The binding affinity of these compounds was evaluated using AR isolated from rat ventral prostate. These second-generation compounds bound the AR in a high affinity and stereoselective manner, with Ki values ranging from about 4 to 130 nM. The ability of these ligands to stimulate AR-mediated transcriptional activation was examined in cells transfected with the human AR and a hormone-dependent luciferase reporter gene. Although some compounds were unable to stimulate AR-mediated transcription, several demonstrated activity similar to that of dihydrotestosterone (DHT, an endogenous steroidal ligand for the AR). We also evaluated the in vivo pharmacologic activity of selected compounds in castrated male rats. Three compounds were identified as selective androgen receptor modulators (SARMs), exhibiting significant anabolic activity while having only moderate to minimal androgenic activity in vivo. PMID:14761201
Impact of androgen and dietary advanced glycation end products on female rat liver.
Palioura, Eleni; Palimeri, Sotiria; Piperi, Christina; Sakellariou, Stratigoula; Kandaraki, Eleni; Sergentanis, Theodoros; Levidou, Georgia; Agrogiannis, George; Papalois, Apostolos; Korkolopoulou, Penelope; Diamanti-Kandarakis, Evanthia; Papavassiliou, Athanasios G
2015-01-01
Advanced glycation end products (AGEs) have been related to a wide range of liver disorders including hyperandrogenic states such as the Polycystic Ovary Syndrome (PCOS). The aim of the present study is to evaluate the potential impact of dietary glycotoxins exposure and androgen excess on hepatic histology and biochemistry in an androgenized female rat model. The study population consisted of 80 female Wistar rats, divided in 3 groups, a group of prepubertal (Group A, n=30) and adult rats (Group B, n=20) that were androgenized via subcutaneous implantation of dihydrotestosterone-containing pellets as well as a group of adult non-androgenized rodents (Group C, n=30). All groups were randomly assigned either to a high-AGE or low-AGE diet for 3 months. Rats fed with a high-AGE diet exhibited significantly elevated levels of gamma-glutamyl transferase (x03B3;GT) (p≤0.0002) and indices of AGE immunostaining in liver tissue (p<0.01) when compared to the respective low-AGE group, while aspartate aminotransferase (AST) levels were affected only in non-androgenized animals (p=0.0002). Androgenization per se constitutes an aggravating factor as demonstrated by the elevated x03B3;GT levels in adult androgenized animals compared to non-androgenized, independent of diet content (p=0.0002) and by the elevated AST and alanine aminotransferase (ALT) levels in low-AGE subgroups (adult androgenized vs. non-androgenized, p=0.0002) followed by increased immunohistochemical AGE deposition in hepatocytes of the latter categories (p=0.0007). The present study suggests that androgens and glycotoxins may contribute synergistically to distort hepatic physiology and function as observed in hyperandrogenic conditions. © 2015 The Author(s) Published by S. Karger AG, Basel.
Dijkstra, Cor; Tagliavini, James; Goerlich, Vivian C.; Groothuis, Ton G. G.
2010-01-01
Recent studies have demonstrated that carotenoid-based traits are under the control of testosterone (T) by up-regulation of carotenoid carriers (lipoproteins) and/or tissue-specific uptake of carotenoids. T can be converted to dihydrotestosterone (DHT) and estradiol (E2), and variation in conversion rate may partly explain some contradictory findings in the literature. Moreover, most studies on the effect of T on sexual signals have focused on the male sex only, while in many species females show the same signal, albeit to a lesser extent. We studied the effects of T, DHT, and E2 treatment in male and female diamond doves Geopelia cuneata in which both sexes have an enlarged red eye ring, which is more pronounced in males. We first showed that this periorbital ring contains very high concentration of carotenoids, of which most are lutein esters. Both T and DHT were effective in enhancing hue, UV-chroma and size in both sexes, while E2 was ineffective. However, E2 dramatically increased the concentration of circulating lipoproteins. We conclude that in both sexes both color and size of the secondary sexual trait are androgen dependent. The action of androgens is independent of lipoproteins regulation. Potential mechanisms and their consequences for trade-off are discussed. PMID:20824278
Targeted Androgen Pathway Suppression in Localized Prostate Cancer: A Pilot Study
Mostaghel, Elahe A.; Nelson, Peter S.; Lange, Paul; Lin, Daniel W.; Taplin, Mary Ellen; Balk, Steven; Ellis, William; Kantoff, Philip; Marck, Brett; Tamae, Daniel; Matsumoto, Alvin M.; True, Lawrence D.; Vessella, Robert; Penning, Trevor; Hunter Merrill, Rachel; Gulati, Roman; Montgomery, Bruce
2014-01-01
Purpose Ligand-mediated activation of the androgen receptor (AR) is critical for prostate cancer (PCa) survival and proliferation. The failure to completely ablate tissue androgens may limit suppression of PCa growth. We evaluated combinations of CYP17A and 5-α-reductase inhibitors for reducing prostate androgen levels, AR signaling, and PCa volumes. Patients and Methods Thirty-five men with intermediate/high-risk clinically localized PCa were randomly assigned to goserelin combined with dutasteride (ZD), bicalutamide and dutasteride (ZBD), or bicalutamide, dutasteride, and ketoconazole (ZBDK) for 3 months before prostatectomy. Controls included patients receiving combined androgen blockade with luteinizing hormone-releasing hormone agonist and bicalutamide. The primary outcome measure was tissue dihydrotestosterone (DHT) concentration. Results Prostate DHT levels were substantially lower in all experimental arms (0.02 to 0.04 ng/g v 0.92 ng/g in controls; P < .001). The ZBDK group demonstrated the greatest percentage decline in serum testosterone, androsterone, and dehydroepiandrosterone sulfate (P < .05 for all). Staining for AR and the androgen-regulated genes prostate-specific antigen and TMPRSS2 was strongly suppressed in benign glands and moderately in malignant glands (P < .05 for all). Two patients had pathologic complete response, and nine had ≤ 0.2 cm3 of residual tumor (defined as a near-complete response), with the largest numbers of complete and near-complete responses in the ZBDK group. Conclusion Addition of androgen synthesis inhibitors lowers prostate androgens below that achieved with standard therapy, but significant AR signaling remains. Tissue-based analysis of steroids and AR signaling is critical to informing the search for optimal local and systemic control of high-risk prostate cancer. PMID:24323034
Androgen Supplementation During Aging: Development of a Physiologically Appropriate Protocol
Sorwell, Krystina G.; Garyfallou, Vasilios T.; Garten, Jamie; Weiss, Alison; Renner, Laurie; Neuringer, Martha; Kohama, Steven G.
2014-01-01
Abstract Men show an age-related decline in the circulating levels of testosterone (T) and dehydroepiandrosterone sulfate (DHEAS). Consequently, there is interest in developing androgen supplementation paradigms for old men that replicate the hormone profiles of young adults. In the present study, we used old (21–26 years old) male rhesus monkeys as a model to examine the efficacy of an androgen supplementation paradigm that comprised oral T administration (12 mg/kg body weight, dissolved in sesame oil/chocolate) in the evening, and two oral DHEA administrations, 3 hr apart (0.04 mg/kg body weight, dissolved in sesame oil/chocolate) in the morning. After 5 days of repeated hormone supplementation, serial blood samples were remotely collected from each animal hourly across the 24-hr day, and assayed for cortisol, DHEAS, T, 5α-dihydrotestosterone (DHT), estrone (E1), and 17β-estradiol (E2). Following androgen supplementation, T levels were significantly elevated and this was associated with a more sustained nocturnal elevation of T's primary bioactive metabolites, DHT and E1 and E2. Plasma DHEAS levels were also significantly elevated after androgen supplementation; DHEAS levels rose in the early morning and gradually declined during the course of the day, closely mimicking the profiles observed in young adults (7–12 years old); in contrast, cortisol levels were unaltered by the supplementation. Together the data demonstrate a non-invasive androgen supplementation paradigm that restores youthful circulating androgen levels in old male primates. Because this paradigm preserves the natural circulating circadian hormone patterns, we predict that it will produce fewer adverse side effects, such as perturbed sleep or cognitive impairment. PMID:24134213
Marcelli, M; Zoppi, S; Wilson, C M; Griffin, J E; McPhaul, M J
1994-01-01
We have investigated the basis of androgen resistance in seven unrelated individuals with complete testicular feminization or Reifenstein syndrome caused by single amino acid substitutions in the hormone-binding domain of the androgen receptor. Monolayer-binding assays of cultured genital skin fibroblasts demonstrated absent ligand binding, qualitative abnormalities of androgen binding, or a decreased amount of qualitatively normal receptor. The consequences of these mutations were examined by introducing the mutations by site-directed mutagenesis into the androgen receptor cDNA sequence and expressing the mutant cDNAs in mammalian cells. The effects of the amino acid substitutions on the binding of different androgens and on the capacity of the ligand-bound receptors to activate a reporter gene were investigated. Substantial differences were found in the responses of the mutant androgen receptors to incubation with testosterone, 5 alpha-dihydrotestosterone, and mibolerone. In several instances, increased doses of hormone or increased frequency of hormone addition to the incubation medium resulted in normal or near normal activation of a reporter gene by cells expressing the mutant androgen receptors. These studies suggest that the stability of the hormone receptor complex is a major determinant of receptor function in vivo. Images PMID:7929841
Preis, Anna; Mugisha, Lawrence; Hauser, Barbara; Weltring, Anja; Deschner, Tobias
2011-12-01
The primary male androgen testosterone (T) is often used as an endocrinological marker to investigate androgen-behaviour interactions in males. In chimpanzees and bonobos, studies investigating the relationship between T levels and dominance rank or aggressive behaviour have revealed contradictory results. The immunoassays used in these studies were originally developed for the measurement of steroids in serum. Their application to non-invasively collected samples, however, can lead to methodological problems due to cross-reacting metabolites, which might occur in urine or faeces but not in blood. The overall aim of this study, therefore, is to clarify whether a T enzyme immunoassay (EIA) is an applicable method to monitor testicular function in adult male chimpanzees. To estimate the impact of cross-reacting androgens on the used T EIA, we compared the results of an EIA measurement with a set of androgen metabolite levels measured by LC-MS. In urine from male chimpanzees, cross-reactivities appear to exist mainly with T and its exclusive metabolites, 5α-dihydrotestosterone (5α-DHT) and 5α-androstanediol (androstanediol). Both urinary and serum T levels of male chimpanzees were significantly higher than female T levels when measured with the T EIA, indicating a reliable measurement of testicular androgens and their exclusive metabolites with the used EIA. In urine from female chimpanzees, the comparison between LC-MS and T EIA results indicated a higher impact of cross-reactions with adrenal androgen metabolites. Therefore, the investigation of urinary T levels in female chimpanzees with a T EIA seems to be problematic. Overall our results show that a T EIA can be a reliable method to monitor testicular function in male chimpanzee urine and that LC-MS is a valuable tool for the validation of immunoassays. Copyright © 2011 Elsevier Inc. All rights reserved.
Goulis, Dimitrios G; Iliadou, Paschalia K; Papanicolaou, Athanasios; Georgiou, Ioannis; Chatzikyriakidou, Anthi; Gerou, Spiridon; Bondis, Ioannis N; Papadimas, Ioannis
2006-01-01
An 18-year old, phenotypically female individual was examined for primary amenorrhea. Three months before her referral, the patient underwent surgery and a pelvic mass was removed. The physical examination revealed normal female external genitalia, normal breast development, sparse pubic hair and absence of axillary hair. The gynecological examination revealed a short blind vagina pouch and absence of cervix and uterus. Serum testosterone and dihydrotestosterone levels were very high. Karyotype was that of a normal male (46,XY). The transabdominal ultrasound, computed tomography (CT) and Magnetic resonance imaging (MRI) showed absence of uterus and fallopian tubes and revealed testis-like gonads located at the internal opening of the inguinal canal bilaterally. Bilateral gonadectomy was subsequently performed. The pathology report was that of "hamartomatous testes" and associated paratesticular leiomyoma. The clinical, laboratory, imaging, genetic and histological findings confirmed the diagnosis of complete androgen insensitivity syndrome. DNA analysis revealed a R831X mutation in exon 7 of the androgen receptor gene. A Sertoli-cell dynamic test showed elevated basal serum inhibin-B and anti-Müllerian hormone levels without further rise following FSH stimulation. The patient was started on hormone replacement therapy with conjugated estrogens. Complete androgen insensitivity syndrome must be considered in any case of primary amenorrhea. Gonadectomy must be planned to eliminate the risk of gonadal malignancy.
Direct Regulation of Androgen Receptor Activity by Potent CYP17 Inhibitors in Prostate Cancer Cells*
Soifer, Harris S.; Souleimanian, Naira; Wu, Sijian; Voskresenskiy, Anatoliy M.; Kisaayak Collak, Filiz; Cinar, Bekir; Stein, Cy A.
2012-01-01
TOK-001 and abiraterone are potent 17-heteroarylsteroid (17-HAS) inhibitors of Cyp17, one of the rate-limiting enzymes in the biosynthesis of testosterone from cholesterol in prostate cancer cells. Nevertheless, the molecular mechanism underlying the prevention of prostate cell growth by 17-HASs still remains elusive. Here, we assess the effects of 17-HASs on androgen receptor (AR) activity in LNCaP and LAPC-4 cells. We demonstrate that both TOK-001 and abiraterone reduced AR protein and mRNA expression, and antagonized AR-dependent promoter activation induced by androgen. TOK-001, but not abiraterone, is an effective apparent competitor of the radioligand [3H]R1881 for binding to the wild type and various mutant AR (W741C, W741L) proteins. In agreement with these data, TOK-001 is a consistently superior inhibitor than abiraterone of R1881-induced transcriptional activity of both wild type and mutant AR. However, neither agent was able to trans-activate the AR in the absence of R1881. Our data demonstrate that phospho-4EBP1 levels are significantly reduced by TOK-001 and to a lesser extent by abiraterone alcohol, and suggest a mechanism by which cap-dependent translation is suppressed by blocking assembly of the eIF4F and eIF4G complex to the mRNA 5′ cap. Thus, the effects of these 17-HASs on AR signaling are complex, ranging from a decrease in testosterone production through the inhibition of Cyp17 as previously described, to directly reducing both AR protein expression and R1881-induced AR trans-activation. PMID:22174412
Developmental programming by androgen affects the circadian timing system in female mice.
Mereness, Amanda L; Murphy, Zachary C; Sellix, Michael T
2015-04-01
Circadian clocks play essential roles in the timing of events in the mammalian hypothalamo-pituitary-ovarian (HPO) axis. The molecular oscillator driving these rhythms has been localized to tissues of the HPO axis. It has been suggested that synchrony among these oscillators is a feature of normal reproductive function. The impact of fertility disorders on clock function and the role of the clock in the etiology of endocrine pathology remain unknown. Polycystic ovarian syndrome (PCOS) is a particularly devastating fertility disorder, affecting 5%-10% of women at childbearing age with features including a polycystic ovary, anovulation, and elevated serum androgen. Approximately 40% of these women have metabolic syndrome, marked by hyperinsulinemia, dyslipidemia, and insulin resistance. It has been suggested that developmental exposure to excess androgen contributes to the etiology of fertility disorders, including PCOS. To better define the role of the timing system in these disorders, we determined the effects of androgen-dependent developmental programming on clock gene expression in tissues of the metabolic and HPO axes. Female PERIOD2::luciferase (PER2::LUC) mice were exposed to androgen (dihydrotestosterone [DHT]) in utero (Days 16-18 of gestation) or for 9-10 wk (DHT pellet) beginning at weaning (pubertal androgen excess [PAE]). As expected, both groups of androgen-treated mice had disrupted estrous cycles. Analysis of PER2::LUC expression in tissue explants revealed that excess androgen produced circadian misalignment via tissue-dependent effects on phase distribution. In vitro treatment with DHT differentially affected the period of PER2::LUC expression in tissue explants and granulosa cells, indicating that androgen has direct and tissue-specific effects on clock gene expression that may account for the effects of developmental programming on the timing system. © 2015 by the Society for the Study of Reproduction, Inc.
Marti, Nesa; Galván, José A; Pandey, Amit V; Trippel, Mafalda; Tapia, Coya; Müller, Michel; Perren, Aurel; Flück, Christa E
2017-02-05
Recently, dihydrotestosterone biosynthesis through the backdoor pathway has been implicated for the human testis in addition to the classic pathway for testosterone (T) synthesis. In the human ovary, androgen precursors are crucial for estrogen synthesis and hyperandrogenism in pathologies such as the polycystic ovary syndrome is partially due to ovarian overproduction. However, a role for the backdoor pathway is only established for the testis and the adrenal, but not for the human ovary. To investigate whether the backdoor pathway exists in normal and PCOS ovaries, we performed specific gene and protein expression studies on ovarian tissues. We found aldo-keto reductases (AKR1C1-1C4), 5α-reductases (SRD5A1/2) and retinol dehydrogenase (RoDH) expressed in the human ovary, indicating that the ovary might produce dihydrotestosterone via the backdoor pathway. Immunohistochemical studies showed specific localization of these proteins to the theca cells. PCOS ovaries show enhanced expression, what may account for the hyperandrogenism. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Nagata, Naoya; Miyakawa, Motonori; Amano, Seiji; Furuya, Kazuyuki; Yamamoto, Noriko; Inoguchi, Kiyoshi
2011-03-15
Some tricyclic tetrahydroquinolines (THQs) were found to have the potential of a new series of nonsteroidal selective androgen receptor modulators (SARMs). Compound 5b was first designed and synthesized under our hypothesis based on a four-point pharmacophoric requirement of the 3-carbonyl, 18-methyl, 17-hydroxyl, and 13-quaternary carbon groups of dihydrotestosterone (DHT). It was revealed that this compound exhibits not only a strong androgen receptor (AR) agonistic activity (EC(50)=9.2 nM) but also the highest selectivity in binding affinity to AR among the steroid hormone receptors. Furthermore, this compound showed a weak virilizing effect with retention of the desired anabolic effect as compared with DHT in vivo. Copyright © 2011 Elsevier Ltd. All rights reserved.
Lao, Kejing; Sun, Jie; Wang, Chong; Wang, Ying; You, Qidong; Xiao, Hong; Xiang, Hua
2017-09-01
Prostate cancer (PCa) is the second leading cause of death in men. Recently, some researches have showed that 5α-reductase inhibitors were beneficial in PCa treatment as well. In this study, a series of novel 3-oxo-4-oxa-5α-androst-17β-amide derivatives have been designed and synthesized in a more simple and convenient method. Most of the synthesized compounds displayed good 5α-reductase inhibitory activities and androgen receptor binding affinities. Their anti-proliferation activities in PC-3 and LNCaP cell lines were also evaluated and the results indicated that most of the synthesized compounds exhibited potent anti-proliferative activities. It is obvious that the androgen-dependent cell line LNCaP was much more sensitive than the androgen-independent cell line PC-3. Among all the synthesized compounds, 11d and 11k displayed the best inhibition activity with 4-fold more sensitive toward LNCaP than PC-3, which was consistent with their high affinities observed in AR binding assay. Molecular modeling studies suggested that 11k could bind to AR in a manner similar to the binding of dihydrotestosterone to AR. Compared to the finasteride, 11k showed a longer plasma half-life (4h) and a better bioavailability. Overall, based on biological activities data, compound 11d and 11k can be identified as potential dual 5α-reductase inhibitors and AR antagonists which might be of therapeutic importance for prostate cancer treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.
Marshall, Elaine; Lowrey, Jacqueline; MacPherson, Sheila; Maybin, Jacqueline A.; Collins, Frances; Critchley, Hilary O. D.
2011-01-01
Context: The endometrium is a multicellular, steroid-responsive tissue that undergoes dynamic remodeling every menstrual cycle in preparation for implantation and, in absence of pregnancy, menstruation. Androgen receptors are present in the endometrium. Objective: The objective of the study was to investigate the impact of androgens on human endometrial stromal cells (hESC). Design: Bioinformatics was used to identify an androgen-regulated gene set and processes associated with their function. Regulation of target genes and impact of androgens on cell function were validated using primary hESC. Setting: The study was conducted at the University Research Institute. Patients: Endometrium was collected from women with regular menses; tissues were used for recovery of cells, total mRNA, or protein and for immunohistochemistry. Results: A new endometrial androgen target gene set (n = 15) was identified. Bioinformatics revealed 12 of these genes interacted in one pathway and identified an association with control of cell survival. Dynamic androgen-dependent changes in expression of the gene set were detected in hESC with nine significantly down-regulated at 2 and/or 8 h. Treatment of hESC with dihydrotestosterone reduced staurosporine-induced apoptosis and cell migration/proliferation. Conclusions: Rigorous in silico analysis resulted in identification of a group of androgen-regulated genes expressed in human endometrium. Pathway analysis and functional assays suggest androgen-dependent changes in gene expression may have a significant impact on stromal cell proliferation, migration, and survival. These data provide the platform for further studies on the role of circulatory or local androgens in the regulation of endometrial function and identify androgens as candidates in the pathogenesis of common endometrial disorders including polycystic ovarian syndrome, cancer, and endometriosis. PMID:21865353
Excess androgen during puberty disrupts circadian organization in female rats.
Sellix, Michael T; Murphy, Zachary C; Menaker, Michael
2013-04-01
Circadian clocks have been described in each tissue of the hypothalamo-pituitary-ovarian axis. Although a role for the clock in the timing of ovulation is indicated, the impact of diseases that disrupt fertility on clock function or the clocks' role in the etiology of these pathologies has yet to be fully appreciated. Polycystic ovary syndrome (PCOS) is a particularly devastating endocrinopathy, affecting approximately 10% of women at childbearing age. Common features of PCOS are a polycystic ovary, amenorrhea, and excess serum androgen. Approximately 40% of these women have metabolic syndrome, including hyperinsulinemia, dyslipidemia, and hyperleptinemia. It has been suggested that excess androgen is a critical factor in the etiology of PCOS. We have examined the effects of androgen excess during puberty on the phase of circadian clocks in tissues of the metabolic and hypothalamo-pituitary-ovarian axes. Female period1-luciferase (per1-luc) rats were exposed to androgen (5α-dihydrotestosterone [DHT]) or placebo for 4-6 weeks (short term) or 9-15 weeks (long term). As expected, DHT-treated animals gained more weight than controls and had disrupted estrous cycles. At the end of treatment, tissues, including the liver, lung, kidney, white adipose, cornea, pituitary, oviduct, and ovarian follicles, were cultured, and per1-luc expression in each was recorded. Analysis of per1-luc expression revealed that DHT exposure increased phase distribution of multiple oscillators, including ovarian follicles, liver, and adipose, and altered phase synchrony between animals. These data suggest that excess androgen during puberty, a common feature of PCOS, negatively affects internal circadian organization in both the reproductive and metabolic axes.
Excess Androgen During Puberty Disrupts Circadian Organization in Female Rats
Murphy, Zachary C.; Menaker, Michael
2013-01-01
Circadian clocks have been described in each tissue of the hypothalamo-pituitary-ovarian axis. Although a role for the clock in the timing of ovulation is indicated, the impact of diseases that disrupt fertility on clock function or the clocks' role in the etiology of these pathologies has yet to be fully appreciated. Polycystic ovary syndrome (PCOS) is a particularly devastating endocrinopathy, affecting approximately 10% of women at childbearing age. Common features of PCOS are a polycystic ovary, amenorrhea, and excess serum androgen. Approximately 40% of these women have metabolic syndrome, including hyperinsulinemia, dyslipidemia, and hyperleptinemia. It has been suggested that excess androgen is a critical factor in the etiology of PCOS. We have examined the effects of androgen excess during puberty on the phase of circadian clocks in tissues of the metabolic and hypothalamo-pituitary-ovarian axes. Female period1-luciferase (per1-luc) rats were exposed to androgen (5α-dihydrotestosterone [DHT]) or placebo for 4-6 weeks (short term) or 9-15 weeks (long term). As expected, DHT-treated animals gained more weight than controls and had disrupted estrous cycles. At the end of treatment, tissues, including the liver, lung, kidney, white adipose, cornea, pituitary, oviduct, and ovarian follicles, were cultured, and per1-luc expression in each was recorded. Analysis of per1-luc expression revealed that DHT exposure increased phase distribution of multiple oscillators, including ovarian follicles, liver, and adipose, and altered phase synchrony between animals. These data suggest that excess androgen during puberty, a common feature of PCOS, negatively affects internal circadian organization in both the reproductive and metabolic axes. PMID:23417420
Caldwell, Aimee S L; Edwards, Melissa C; Desai, Reena; Jimenez, Mark; Gilchrist, Robert B; Handelsman, David J; Walters, Kirsty A
2017-04-18
Polycystic ovary syndrome (PCOS) is a complex hormonal disorder characterized by reproductive, endocrine, and metabolic abnormalities. As the origins of PCOS remain unknown, mechanism-based treatments are not feasible and current management relies on treatment of symptoms. Hyperandrogenism is the most consistent PCOS characteristic; however, it is unclear whether androgen excess, which is treatable, is a cause or a consequence of PCOS. As androgens mediate their actions via the androgen receptor (AR), we combined a mouse model of dihydrotestosterone (DHT)-induced PCOS with global and cell-specific AR-resistant (ARKO) mice to investigate the locus of androgen actions that mediate the development of the PCOS phenotype. Global loss of the AR reveals that AR signaling is required for all DHT-induced features of PCOS. Neuron-specific AR signaling was required for the development of dysfunctional ovulation, classic polycystic ovaries, reduced large antral follicle health, and several metabolic traits including obesity and dyslipidemia. In addition, ovariectomized ARKO hosts with wild-type ovary transplants displayed normal estrous cycles and corpora lutea, despite DHT treatment, implying extraovarian and not intraovarian AR actions are key loci of androgen action in generating the PCOS phenotype. These findings provide strong evidence that neuroendocrine genomic AR signaling is an important extraovarian mediator in the development of PCOS traits. Thus, targeting AR-driven mechanisms that initiate PCOS is a promising strategy for the development of novel treatments for PCOS.
Nonsteroidal selective androgen receptor modulators enhance female sexual motivation.
Jones, Amanda; Hwang, Dong Jin; Duke, Charles B; He, Yali; Siddam, Anjaiah; Miller, Duane D; Dalton, James T
2010-08-01
Women experience a decline in estrogen and androgen levels after natural or surgically induced menopause, effects that are associated with a loss of sexual desire and bone mineral density. Studies in our laboratories have shown the beneficial effects of selective androgen receptor modulators (SARMs) in the treatment of osteoporosis and muscle wasting in animal models. A series of S-3-(phenoxy)-2-hydroxy-2-methyl-N-(4-cyano-3-trifluoromethyl-phenyl)-propionamide analogs was synthesized to evaluate the effects of B-ring substitutions on in vitro and in vivo pharmacologic activity, especially female sexual motivation. The androgen receptor (AR) relative binding affinities ranged from 0.1 to 26.5% (relative to dihydrotestosterone) and demonstrated a range of agonist activity at 100 nM. In vivo pharmacologic activity was first assessed by using male rats. Structural modifications to the B-ring significantly affected the selectivity of the SARMs, demonstrating that single-atom substitutions can dramatically and unexpectedly influence activity in androgenic (i.e., prostate) and anabolic (i.e., muscle) tissues. (S)-N-(4-cyano-3-trifluoromethyl-phenyl)-3-(3-fluoro,4-chlorophenoxy)-2-hydroxy-2-methyl-propanamide (S-23) displayed full agonist activity in androgenic and anabolic tissues; however, the remaining SARMs were more prostate-sparing, selectively maintaining the size of the levator ani muscle in castrated rats. The partner-preference paradigm was used to evaluate the effects of SARMs on female sexual motivation. With the exception of two four-halo substituted analogs, the SARMs increased sexual motivation in ovariectomized rats, with potency and efficacy comparable with testosterone propionate. These results indicate that the AR is important in regulating female libido given the nonaromatizable nature of SARMs and it could be a superior alternative to steroidal testosterone preparations in the treatment of hypoactive sexual desire disorder.
Nonsteroidal Selective Androgen Receptor Modulators Enhance Female Sexual Motivation
Jones, Amanda; Hwang, Dong Jin; Duke, Charles B.; He, Yali; Siddam, Anjaiah; Miller, Duane D.
2010-01-01
Women experience a decline in estrogen and androgen levels after natural or surgically induced menopause, effects that are associated with a loss of sexual desire and bone mineral density. Studies in our laboratories have shown the beneficial effects of selective androgen receptor modulators (SARMs) in the treatment of osteoporosis and muscle wasting in animal models. A series of S-3-(phenoxy)-2-hydroxy-2-methyl-N-(4-cyano-3-trifluoromethyl-phenyl)-propionamide analogs was synthesized to evaluate the effects of B-ring substitutions on in vitro and in vivo pharmacologic activity, especially female sexual motivation. The androgen receptor (AR) relative binding affinities ranged from 0.1 to 26.5% (relative to dihydrotestosterone) and demonstrated a range of agonist activity at 100 nM. In vivo pharmacologic activity was first assessed by using male rats. Structural modifications to the B-ring significantly affected the selectivity of the SARMs, demonstrating that single-atom substitutions can dramatically and unexpectedly influence activity in androgenic (i.e., prostate) and anabolic (i.e., muscle) tissues. (S)-N-(4-cyano-3-trifluoromethyl-phenyl)-3-(3-fluoro,4-chlorophenoxy)-2-hydroxy-2-methyl-propanamide (S-23) displayed full agonist activity in androgenic and anabolic tissues; however, the remaining SARMs were more prostate-sparing, selectively maintaining the size of the levator ani muscle in castrated rats. The partner-preference paradigm was used to evaluate the effects of SARMs on female sexual motivation. With the exception of two four-halo substituted analogs, the SARMs increased sexual motivation in ovariectomized rats, with potency and efficacy comparable with testosterone propionate. These results indicate that the AR is important in regulating female libido given the nonaromatizable nature of SARMs and it could be a superior alternative to steroidal testosterone preparations in the treatment of hypoactive sexual desire disorder. PMID:20444881
Izumi, Koji; Zheng, Yichun; Hsu, Jong-Wei; Chang, Chawnshang; Miyamoto, Hiroshi
2013-02-01
UDP-glucuronosyltransferases (UGTs), major phase II drug metabolism enzymes, play an important role in urinary bladder cancer initiation by detoxifying carcinogens. We aimed to determine if androgens regulate UGT expression via the androgen receptor (AR) pathway in the bladder. Real-time reverse transcription-polymerase chain reaction and Western blot analyses were used to assess UGT1A levels in the normal urothelium SVHUC cell line stably expressed with AR and in bladder tissues from AR knockout (ARKO) and castrated male mice. Immunohistochemistry was also performed in radical cystectomy specimens. Dihydrotestosterone (DHT) treatment in SVHUC-AR reduced mRNA expression of all the UGT1A subtypes (19-75% decrease), and hydroxyflutamide antagonized the DHT effects. In contrast, DHT showed only marginal effects on UGT1A expression in SVHUC-Vector. Of note were higher expression levels of UGT1As in SVHUC-Vector than in SVHUC-AR. In ARKO mice, all the Ugt1a subtypes were up-regulated, compared to wild-type littermates. In wild-type male mice, castration increased the expression of Ugt1a8, Ugt1a9, and Ugt1a10. Additionally, wild-type female mice had higher levels of Ugt1a than wild-type males. Immunohistochemical studies showed strong (3+) UGT1A staining in 11/24 (46%) cancer tissues, which was significantly lower than in corresponding benign tissues [17/18 (94%) cases (P = 0.0009)]. These results suggest that androgen-mediated AR signals promote bladder carcinogenesis by down-regulating the expression of UGTs in the bladder. Copyright © 2011 Wiley Periodicals, Inc.
O’Reilly, Michael W.; Kempegowda, Punith; Walsh, Mark; Taylor, Angela E.; Manolopoulos, Konstantinos N.; Allwood, J. William; Semple, Robert K.; Hebenstreit, Daniel; Dunn, Warwick B.; Tomlinson, Jeremy W.
2017-01-01
Context: Polycystic ovary syndrome (PCOS) is a prevalent metabolic disorder occurring in up to 10% of women of reproductive age. PCOS is associated with insulin resistance and cardiovascular risk. Androgen excess is a defining feature of PCOS and has been suggested as causally associated with insulin resistance; however, mechanistic evidence linking both is lacking. We hypothesized that adipose tissue is an important site linking androgen activation and metabolic dysfunction in PCOS. Methods: We performed a human deep metabolic in vivo phenotyping study examining the systemic and intra-adipose effects of acute and chronic androgen exposure in 10 PCOS women, in comparison with 10 body mass index–matched healthy controls, complemented by in vitro experiments. Results: PCOS women had increased intra-adipose concentrations of testosterone (P = 0.0006) and dihydrotestosterone (P = 0.01), with increased expression of the androgen-activating enzyme aldo-ketoreductase type 1 C3 (AKR1C3) (P = 0.04) in subcutaneous adipose tissue. Adipose glycerol levels in subcutaneous adipose tissue microdialysate supported in vivo suppression of lipolysis after acute androgen exposure in PCOS (P = 0.04). Mirroring this, nontargeted serum metabolomics revealed prolipogenic effects of androgens in PCOS women only. In vitro studies showed that insulin increased adipose AKR1C3 expression and activity, whereas androgen exposure increased adipocyte de novo lipid synthesis. Pharmacologic AKR1C3 inhibition in vitro decreased de novo lipogenesis. Conclusions: These findings define an intra-adipose mechanism of androgen activation that contributes to adipose remodeling and a systemic lipotoxic metabolome, with intra-adipose androgens driving lipid accumulation and insulin resistance in PCOS. AKR1C3 represents a promising therapeutic target in PCOS. PMID:28645211
O'Reilly, Michael W; Kempegowda, Punith; Walsh, Mark; Taylor, Angela E; Manolopoulos, Konstantinos N; Allwood, J William; Semple, Robert K; Hebenstreit, Daniel; Dunn, Warwick B; Tomlinson, Jeremy W; Arlt, Wiebke
2017-09-01
Polycystic ovary syndrome (PCOS) is a prevalent metabolic disorder occurring in up to 10% of women of reproductive age. PCOS is associated with insulin resistance and cardiovascular risk. Androgen excess is a defining feature of PCOS and has been suggested as causally associated with insulin resistance; however, mechanistic evidence linking both is lacking. We hypothesized that adipose tissue is an important site linking androgen activation and metabolic dysfunction in PCOS. We performed a human deep metabolic in vivo phenotyping study examining the systemic and intra-adipose effects of acute and chronic androgen exposure in 10 PCOS women, in comparison with 10 body mass index-matched healthy controls, complemented by in vitro experiments. PCOS women had increased intra-adipose concentrations of testosterone (P = 0.0006) and dihydrotestosterone (P = 0.01), with increased expression of the androgen-activating enzyme aldo-ketoreductase type 1 C3 (AKR1C3) (P = 0.04) in subcutaneous adipose tissue. Adipose glycerol levels in subcutaneous adipose tissue microdialysate supported in vivo suppression of lipolysis after acute androgen exposure in PCOS (P = 0.04). Mirroring this, nontargeted serum metabolomics revealed prolipogenic effects of androgens in PCOS women only. In vitro studies showed that insulin increased adipose AKR1C3 expression and activity, whereas androgen exposure increased adipocyte de novo lipid synthesis. Pharmacologic AKR1C3 inhibition in vitro decreased de novo lipogenesis. These findings define an intra-adipose mechanism of androgen activation that contributes to adipose remodeling and a systemic lipotoxic metabolome, with intra-adipose androgens driving lipid accumulation and insulin resistance in PCOS. AKR1C3 represents a promising therapeutic target in PCOS. Copyright © 2017 Endocrine Society
Local estrogenic/androgenic balance in the cerebral vasculature
Krause, Diana N.; Duckles, Sue P.; Gonzales, Rayna J.
2011-01-01
Reproductive effects of sex steroids are well-known, however it is increasingly apparent that these hormones have important actions on non-reproductive tissues such as the vasculature. The latter effects can be relevant throughout the lifespan, not just limited to reproductive years, and are not necessarily restricted to one sex or the other. Our work has established that cerebral blood vessels are a non-reproductive target tissue for sex steroids. We have found that estrogen and androgens alter vascular tone, endothelial function, oxidative stress and inflammatory responses in cerebral vessels. Often the actions of estrogen and androgens oppose each other. Moreover, it is clear that cerebral vessels are directly targeted by sex steroids as they express specific receptors for these hormones. Interestingly, cerebral blood vessels also express enzymes that metabolize sex steroids. These findings suggest that local synthesis of 17β-estradiol and dihydrotestosterone can occur within the vessel wall. One of the enzymes present, aromatase, converts testosterone to 17β-estradiol, which would alter the local balance of androgenic and estrogenic influences. Thus cerebral vessels are affected by circulating sex hormones as well as locally synthesized sex steroids. The presence of vascular endocrine effector mechanisms has important implications for male-female differences in cerebrovascular function and disease. Moreover, the cerebral circulation is a target for gonadal hormones as well as anabolic steroids and therapeutic drugs used to manipulate sex steroid actions. The long-term consequences of these influences have yet to be determined. PMID:21535417
Sphingosine Kinase-1 Is Central to Androgen-Regulated Prostate Cancer Growth and Survival
Dayon, Audrey; Brizuela, Leyre; Martin, Claire; Mazerolles, Catherine; Pirot, Nelly; Doumerc, Nicolas; Nogueira, Leonor; Golzio, Muriel; Teissié, Justin; Serre, Guy; Rischmann, Pascal; Malavaud, Bernard; Cuvillier, Olivier
2009-01-01
Background Sphingosine kinase-1 (SphK1) is an oncogenic lipid kinase notably involved in response to anticancer therapies in prostate cancer. Androgens regulate prostate cancer cell proliferation, and androgen deprivation therapy is the standard of care in the management of patients with advanced disease. Here, we explored the role of SphK1 in the regulation of androgen-dependent prostate cancer cell growth and survival. Methodology/Principal Findings Short-term androgen removal induced a rapid and transient SphK1 inhibition associated with a reduced cell growth in vitro and in vivo, an event that was not observed in the hormono-insensitive PC-3 cells. Supporting the critical role of SphK1 inhibition in the rapid effect of androgen depletion, its overexpression could impair the cell growth decrease. Similarly, the addition of dihydrotestosterone (DHT) to androgen-deprived LNCaP cells re-established cell proliferation, through an androgen receptor/PI3K/Akt dependent stimulation of SphK1, and inhibition of SphK1 could markedly impede the effects of DHT. Conversely, long-term removal of androgen support in LNCaP and C4-2B cells resulted in a progressive increase in SphK1 expression and activity throughout the progression to androgen-independence state, which was characterized by the acquisition of a neuroendocrine (NE)-like cell phenotype. Importantly, inhibition of the PI3K/Akt pathway—by negatively impacting SphK1 activity—could prevent NE differentiation in both cell models, an event that could be mimicked by SphK1 inhibitors. Fascinatingly, the reversability of the NE phenotype by exposure to normal medium was linked with a pronounced inhibition of SphK1 activity. Conclusions/Significance We report the first evidence that androgen deprivation induces a differential effect on SphK1 activity in hormone-sensitive prostate cancer cell models. These results also suggest that SphK1 activation upon chronic androgen deprivation may serve as a compensatory mechanism
Grassi, Silvarosa; Scarduzio, Mariangela; Panichi, Roberto; Dall'Aglio, Cecilia; Boiti, Cristiano; Pettorossi, Vito E
2013-08-01
In brainstem slices of male rats, we examined in single neurons of the medial vestibular nucleus (MVN) the effect of exogenous administration of estrogenic (17β-estradiol, E2) and androgenic (5α-dihydrotestosterone, DHT) steroids on the synaptic response to vestibular afferent stimulation. By whole cell patch clamp recordings we showed that E2 induced synaptic long-term potentiation (LTP) that was cancelled by the subsequent administration of DHT. Conversely, DHT induced synaptic long-term depression (LTD) that was partially reversed by E2. The electrophysiological findings were supported by immunohistochemical analysis showing the presence of estrogen (ER: α and β) and androgen receptors (AR) in the MVN neurons. We found that a large number of neurons were immunoreactive for ERα, ERβ, and AR and most of them co-localized ERβ and AR. We also showed the presence of P450-aromatase (ARO) in the MVN neurons, clearly proving that E2 can be locally synthesized in the MVN. On the whole, these results demonstrate a role of estrogenic and androgenic signals in modulating vestibular synaptic plasticity and suggest that the enhancement or depression of vestibular synaptic response may depend on the local conversion of T into E2 or DHT. Copyright © 2013 Elsevier Inc. All rights reserved.
Androgens regulate scarless repair of the endometrial "wound" in a mouse model of menstruation.
Cousins, Fiona L; Kirkwood, Phoebe M; Murray, Alison A; Collins, Frances; Gibson, Douglas A; Saunders, Philippa T K
2016-08-01
The human endometrium undergoes regular cycles of synchronous tissue shedding (wounding) and repair that occur during menstruation before estrogen-dependent regeneration. Endometrial repair is normally both rapid and scarless. Androgens regulate cutaneous wound healing, but their role in endometrial repair is unknown. We used a murine model of simulated menses; mice were treated with a single dose of the nonaromatizable androgen dihydrotestosterone (DHT; 200 µg/mouse) to coincide with initiation of tissue breakdown. DHT altered the duration of vaginal bleeding and delayed restoration of the luminal epithelium. Analysis of uterine mRNAs 24 h after administration of DHT identified significant changes in metalloproteinases (Mmp3 and -9; P < 0.01), a snail family member (Snai3; P < 0.001), and osteopontin (Spp1; P < 0.001). Chromatin immunoprecipitation analysis identified putative androgen receptor (AR) binding sites in the proximal promoters of Mmp9, Snai3, and Spp1. Striking spatial and temporal changes in immunoexpression of matrix metalloproteinase (MMP) 3/9 and caspase 3 were detected after DHT treatment. These data represent a paradigm shift in our understanding of the role of androgens in endometrial repair and suggest that androgens may have direct impacts on endometrial tissue integrity. These studies provide evidence that the AR is a potential target for drug therapy to treat conditions associated with aberrant endometrial repair processes.-Cousins, F. L., Kirkwood, P. M., Murray, A. A., Collins, F., Gibson, D. A., Saunders, P. T. K. Androgens regulate scarless repair of the endometrial "wound" in a mouse model of menstruation. © The Author(s).
Androgens and estrogens in skeletal sexual dimorphism
Laurent, Michaël; Antonio, Leen; Sinnesael, Mieke; Dubois, Vanessa; Gielen, Evelien; Classens, Frank; Vanderschueren, Dirk
2014-01-01
Bone is an endocrine tissue expressing androgen and estrogen receptors as well as steroid metabolizing enzymes. The bioactivity of circulating sex steroids is modulated by sex hormone-binding globulin and local conversion in bone tissue, for example, from testosterone (T) to estradiol (E2) by aromatase, or to dihydrotestosterone by 5α-reductase enzymes. Our understanding of the structural basis for gender differences in bone strength has advanced considerably over recent years due to increasing use of (high resolution) peripheral computed tomography. These microarchitectural insights form the basis to understand sex steroid influences on male peak bone mass and turnover in cortical vs trabecular bone. Recent studies using Cre/LoxP technology have further refined our mechanistic insights from global knockout mice into the direct contributions of sex steroids and their respective nuclear receptors in osteoblasts, osteoclasts, osteocytes, and other cells to male osteoporosis. At the same time, these studies have reinforced the notion that androgen and estrogen deficiency have both direct and pleiotropic effects via interaction with, for example, insulin-like growth factor 1, inflammation, oxidative stress, central nervous system control of bone metabolism, adaptation to mechanical loading, etc., This review will summarize recent advances on these issues in the field of sex steroid actions in male bone homeostasis. PMID:24385015
A novel class of pyranocoumarin anti-androgen receptor signaling compounds.
Guo, Junming; Jiang, Cheng; Wang, Zhe; Lee, Hyo-Jeong; Hu, Hongbo; Malewicz, Barbara; Lee, Hyo-Jung; Lee, Jae-Ho; Baek, Nam-In; Jeong, Jin-Hyun; Kim, Dae-Keun; Kang, Kyung-Sun; Kim, Sung-Hoon; Lu, Junxuan
2007-03-01
Androgen and the androgen receptor (AR)-mediated signaling are crucial for prostate cancer development. Novel agents that can inhibit AR signaling in ligand-dependent and ligand-independent manners are desirable for the chemoprevention of prostate carcinogenesis and for the treatment of advanced prostate cancer. We have shown recently that the pyranocoumarin compound decursin from the herb Angelica gigas possesses potent anti-AR activities distinct from the anti-androgen bicalutamide. Here, we compared the anti-AR activities and the cell cycle arrest and apoptotic effects of decursin and two natural analogues in the androgen-dependent LNCaP human prostate cancer cell culture model to identify structure-activity relationships and mechanisms. Decursin and its isomer decursinol angelate decreased prostate-specific antigen expression with IC(50) of approximately 1 mumol/L. Both inhibited the androgen-stimulated AR nuclear translocation and transactivation, decreased AR protein abundance through proteasomal degradation, and induced G(0/1) arrest and morphologic differentiation. They also induced caspase-mediated apoptosis and reactive oxygen species at higher concentrations. Furthermore, they lacked the agonist activity of bicalutamide in the absence of androgen and were more potent than bicalutamide for suppressing androgen-stimulated cell growth. Decursinol, which does not contain a side chain, lacked the reactive oxygen species induction and apoptotic activities and exerted paradoxically an inhibitory and a stimulatory effect on AR signaling and cell growth. In conclusion, decursin and decursinol angelate are members of a novel class of nonsteroidal compounds that exert a long-lasting inhibition of both ligand-dependent and ligand-independent AR signaling. The side chain is critical for sustaining the anti-AR activities and the growth arrest and apoptotic effects.
Hazra, Rasmani; Jimenez, Mark; Desai, Reena; Handelsman, David J; Allan, Charles M
2013-09-01
We recently created a mouse model displaying precocious Sertoli cell (SC) and spermatogenic development induced by SC-specific transgenic androgen receptor expression (TgSCAR). Here we reveal that TgSCAR regulates the development, function, and absolute number of Leydig cells (LCs). Total fetal and adult type LC numbers were reduced in postnatal and adult TgSCAR vs control testes, despite normal circulating LH levels. Normal LC to SC ratios found in TgSCAR testes indicate that SC androgen receptor (SCAR)-mediated activity confers a quorum-dependent relationship between total SC and LC numbers. TgSCAR enhanced LC differentiation, shown by elevated ratios of advanced to immature LC types, and reduced LC proliferation in postnatal TgSCAR vs control testes. Postnatal TgSCAR testes displayed up-regulated expression of coupled ligand-receptor transcripts (Amh-Amhr2, Dhh-Ptch1, Pdgfa-Pdgfra) for potential SCAR-stimulated paracrine pathways, which may coordinate LC differentiation. Neonatal TgSCAR testes displayed normal T and dihydrotestosterone levels despite differential changes to steroidogenic gene expression, with down-regulated Star, Cyp11a1, and Cyp17a1 expression contrasting with up-regulated Hsd3b1, Hsd17b3, and Srd5a1 expression. TgSCAR males also displayed elevated postnatal and normal adult serum testosterone levels, despite reduced LC numbers. Enhanced adult-type LC steroidogenic output was revealed by increased pubertal testicular T, dihydrotestosterone, 3α-diol and 3β-diol levels per LC and up-regulated steroidogenic gene (Nr5a1, Lhr, Cyp11a1, Cyp17a1, Hsd3b6, Srd5a1) expression in pubertal or adult TgSCAR vs control males, suggesting regulatory mechanisms maintain androgen levels independently of absolute LC numbers. Our unique gain-of-function TgSCAR model has revealed that SCAR activity controls temporal LC differentiation, steroidogenic function, and population size.
High abundance androgen receptor in goldfish brain: characteristics and seasonal changes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pasmanik, M.; Callard, G.V.
1988-08-01
Testosterone (T) exerts its actions in brain directly via androgen receptors or, after aromatization to estradiol, via estrogen receptors. Brain aromatase activity in teleost fish is 100-1000 times greater than in mammals and would be expected to significantly reduce the quantity of androgen available for receptor binding. Experiments were carried out on the goldfish Carassius auratus to determine if androgen receptors are present in teleost brain and whether their physicochemical properties reflect elevated aromatase. Cytosolic and nuclear extracts were assayed with the use of (/sup 3/H)T and charcoal, Sephadex LH-20, or DNA-cellulose chromatography to separate bound and free steroids. Bindingmore » activity was saturable and had an equally high affinity for T and 5 alpha-dihydrotestosterone. Although mibolerone was a relatively weak competitor, the putative teleost androgen 11-ketotestosterone, methyltrienolone (R1881), estradiol, progesterone, and cortisol were poor ligands. Characteristics that distinguish this receptor from a steroid-binding protein in goldfish serum are the presence of binding activity in both nuclear and cytosolic extracts, a low rate of ligand-receptor dissociation, electrophoretic mobility, sedimentation properties in low vs. high salt, and tissue distribution. DNA cellulose-adhering and nonadhering forms were detected, but these did not differ in other variables measured. Although goldfish androgen receptors resembled those of mammals in all important physicochemical characteristics, they were unusually abundant compared to levels in rat brain, but comparable to levels in prostate and other male sex hormone target organs. Moreover, there were seasonal variations in total receptors, with a peak at spawning (April) 4- to 5-fold higher than values in reproductively inactive fish.« less
Testosterone and dihydrotestosterone levels in the transition zone correlate with prostate volume.
Pejčić, Tomislav; Tosti, Tomislav; Tešić, Živoslav; Milković, Borivoj; Dragičević, Dejan; Kozomara, Milutin; Čekerevac, Milica; Džamić, Zoran
2017-07-01
There is still no consensus regarding intraprostatic androgen levels and the accumulation of androgens in the hyperplastic prostatic tissue. The current opinion is that intraprostatic dihydrotestosterone (DHT) concentrations are maintained but not elevated in benign prostatic hyperplasia (BPH), while there is no similar data concerning intraprostatic testosterone (T). Tissue T (tT) and tissue DHT (tDHT) concentration were determined in 93 patients scheduled for initial prostate biopsy. The criteria for biopsy were abnormal DRE and/or PSA > 4 ng/mL. Total prostate volume (TPV) was determined by transrectal ultrasound (TRUS). During TRUS- guided prostate biopsy, 10-12 samples were collected from the peripheral zone (PZ) and two additional samples were collected from the transition zone (TZ). The samples from the TZ were immediately frozen in liquid nitrogen at -70°C, and transported for tissue androgen determination, using liquid chromatography mass spectrometry (LC-MS). Pathological analysis revealed that prostate cancer (PCa) was present in 45 and absent in 48 patients. In the whole group, there were 42 men with small prostate (TPV < 30 mL) and 51 with enlarged prostate (TPV ≥ 31 mL). The overall average tT level was 0.79 ± 0.66 ng/g, while the average tDHT level was 10.27 ± 7.15 ng/g. There were no differences in tT and tDHT level in prostates with and without PCa. However, tT and tDHT levels were significantly higher in larger, than in smaller prostates (tT: 1.05 ± 0.75 and 0.46 ± 0.29 ng/g, and tDHT: 15.0 ± 6.09 and 4.51 ± 2.75 ng/g, respectively). There were strong correlations between tT and TPV (r = 0.71), and tDHT and TPV (r = 0.74). The present study confirmed that both T and DHT accumulated in the stroma of enlarged prostates; the degree of accumulation correlated with prostate volume. © 2017 Wiley Periodicals, Inc.
CYP17 inhibitors for prostate cancer therapy
Vasaitis, Tadas S.; Bruno, Robert D.; Njar, Vincent C. O.
2010-01-01
Prostate cancer (PC) is now the second most prevalent cause of death in men in the USA and Europe. At present, the major treatment options include surgical or medical castration. These strategies cause ablation of the production of testosterone (T), dihydrotestosterone (DHT) and related androgens by the testes. However, because these procedures do not affect adrenal, prostate and other tissues androgen production, they are often combined with androgen receptor antagonists to block their action. Indeed, recent studies have unequivocally established that in castration-resistant prostate cancer (CRPC) many androgen-regulated genes become re-expressed and tissue androgen levels increase despite low serum levels. Clearly, inhibition of the key enzyme which catalyzes the biosynthesis of androgens from pregnane precursors, 17α-hydroxy/17,20-lyase (hereafter referred to as CYP17) could prevent androgen production from all sources. Thus, total ablation of androgen production by potent CYP17 inhibitors may provide effective treatment of prostate cancer patients. This review highlights the role of androgen biosynthesis in the progression of prostate cancer and the impact of CYP17 inhibitors, such as ketoconazole, abiraterone acetate, VN/124-1 (TOK-001) and TAK-700 in the clinic and in clinical development. PMID:21092758
Androgens inhibit adipogenesis during human adipose stem cell commitment to predipocyte formation
Chazenbalk, Gregorio; Singh, Prapti; Irge, Dana; Shah, Amy; Abbott, David H; Dumesic, Daniel A
2013-01-01
Androgens play a pivotal role in the regulation of body fat distribution. Adipogenesis is a process whereby multipotent adipose stem cells (ASCs) initially become preadipocytes (ASC commitment to preadipocytes) before differentiating into adipocytes. Androgens inhibit human (h) subcutaneous (SC) abdominal preadipocyte differentiation in both sexes, but their effects on hASC commitment to preadipocyte formation is unknown. We therefore examined whether androgen exposure to human (h) ASCs, isolated from SC abdominal adipose of nonobese women, impairs their commitment to preadipocyte formation and/or subsequent differentiation into adipocytes. For this, isolated hASCs from SC abdominal lipoaspirate were cultured in adipogenesis-inducing medium for 0.5–14 days in the presence of testosterone (T, 0–100 nM) or dihydrotestosterone (DHT, 0–50 nM). Adipogenesis was determined by immunofluorescence microscopy and by quantification of adipogenically relevant transcriptional factors, PPARγ, C/EBPα and C/EBPβ. We found that a 3-day exposure of hASCs to T (50 nM) or DHT (5 nM) in adipogenesis-inducing medium impaired lipid acquisition and decreased PPARγ, C/EBPα and C/EBPβ gene expression. The inhibitory effects of T and DHT at this early-stage of adipocyte differentiation, were partially and completely reversed by flutamide (F, 100 nM), respectively. The effect of androgens on hASC commitment to a preadipocyte phenotype was examined via activation of BMP4 signaling. T (50 nM) and DHT (5nM) significantly inhibited the stimulatory effect of BMP4-induced ASC commitment to the preadipocyte phenotype, as regards PPARγ and C/EBPα gene expression. Our findings indicate that androgens, in part through androgen receptor action, impair BMP4-induced commitment of SC hASCs to preadipocytes and also reduce early-stage adipocyte differentiation, perhaps limiting adipocyte numbers and fat storage in SC abdominal adipose. PMID:23707571
Caldwell, Aimee S. L.; Edwards, Melissa C.; Desai, Reena; Jimenez, Mark; Gilchrist, Robert B.; Walters, Kirsty A.
2017-01-01
Polycystic ovary syndrome (PCOS) is a complex hormonal disorder characterized by reproductive, endocrine, and metabolic abnormalities. As the origins of PCOS remain unknown, mechanism-based treatments are not feasible and current management relies on treatment of symptoms. Hyperandrogenism is the most consistent PCOS characteristic; however, it is unclear whether androgen excess, which is treatable, is a cause or a consequence of PCOS. As androgens mediate their actions via the androgen receptor (AR), we combined a mouse model of dihydrotestosterone (DHT)-induced PCOS with global and cell-specific AR-resistant (ARKO) mice to investigate the locus of androgen actions that mediate the development of the PCOS phenotype. Global loss of the AR reveals that AR signaling is required for all DHT-induced features of PCOS. Neuron-specific AR signaling was required for the development of dysfunctional ovulation, classic polycystic ovaries, reduced large antral follicle health, and several metabolic traits including obesity and dyslipidemia. In addition, ovariectomized ARKO hosts with wild-type ovary transplants displayed normal estrous cycles and corpora lutea, despite DHT treatment, implying extraovarian and not intraovarian AR actions are key loci of androgen action in generating the PCOS phenotype. These findings provide strong evidence that neuroendocrine genomic AR signaling is an important extraovarian mediator in the development of PCOS traits. Thus, targeting AR-driven mechanisms that initiate PCOS is a promising strategy for the development of novel treatments for PCOS. PMID:28320971
Postnatal expression and androgen regulation of HOXBES2 homeoprotein in rat epididymis.
Prabagaran, Esakki; Hegde, Uma C; Moodbidri, Sudhir B; Bandivdekar, Atmaram H; Raghavan, Vijaya P
2007-01-01
The multifunctional and androgen-regulated epididymis is known to provide a conducive microenvironment for the maturation and storage of mature spermatozoa. HOXB2 homeodomain-containing epididymis-specific sperm protein (HOXBES2), a molecule first reported by our group, exhibits cell- and region-specific expression. It was found in the cytoplasm of the principal epithelial cells with maximum in the distal segments of the rat epididymis. The present study was undertaken to determine whether HOXBES2 expression is regulated by androgens and postnatal epididymal development. Toward this, the epididymis was disallowed access to circulating androgens either by chemical or biologic castration. In bilaterally orchidectomized animals, the levels of immunoreactive HOXBES2 declined to <5 % of those seen in sham-operated animals. Exogenous dihydrotestosterone (DHT) supplementation (250 microg/kg body weight) for 7 days restored the expression levels to >or= 90 % of that observed in intact animals. Ethylene dimethane sulfonate (EDS) administration completely abolished HOXBES2 expression in the epididymis, and supplementation with DHT or DHT + estradiol for 10 days re-established HOXBES2 expression to near normalcy. However, in the estradiol alone-supplemented EDS-treated group, HOXBES2 remained undetected. The unaltered HOXBES2 expression following efferent duct ligation suggested that HOXBES2 is not critically dependent on testicular factors. During postnatal development, protein expression in the epididymis begins to appear from day 40 and 50 and increased from day 60 onward, coinciding with the mature levels of circulating androgens and the well-differentiated epididymis. Thus, the data obtained from this study suggests that HOXBES2 expression could be regulated by androgens, and its expression level is closely associated with the postnatal development of the epididymis.
A new dawn for androgens: Novel lessons from 11-oxygenated C19 steroids.
Pretorius, Elzette; Arlt, Wiebke; Storbeck, Karl-Heinz
2017-02-05
The abundant adrenal C19 steroid 11β-hydroxyandrostenedione (11OHA4) has been written off as a dead-end product of adrenal steroidogenesis. However, recent evidence has demonstrated that 11OHA4 is the precursor to the potent androgenic 11-oxygenated steroids, 11-ketotestosterone and 11-ketodihydrotestosterone, that bind and activate the human androgen receptor similarly to testosterone and DHT. The significance of this discovery becomes apparent when considering androgen dependent diseases such as castration resistant prostate cancer and diseases associated with androgen excess, e.g. congenital adrenal hyperplasia and polycystic ovary syndrome. In this review we describe the production and metabolism of 11-oxygenated steroids. We subsequently discuss their androgenic activity and highlight the putative role of these androgens in disease states. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Laurent, Michaël R; Jardí, Ferran; Dubois, Vanessa; Schollaert, Dieter; Khalil, Rougin; Gielen, Evelien; Carmeliet, Geert; Claessens, Frank; Vanderschueren, Dirk
2016-12-01
Aging hypogonadal men are at increased risk of osteoporosis and sarcopenia. Testosterone is a potentially appealing strategy to prevent simultaneous bone and muscle loss. The androgen receptor (AR) mediates antiresorptive effects on trabecular bone via osteoblast-lineage cells, as well as muscle-anabolic actions. Sex steroids also modify the skeletal response to mechanical loading. However, it is unclear whether the effects of androgens on bone remain effective independent of mechanical stimulation or rather require indirect androgen effects via muscle. This study aims to characterize the effects and underlying mechanisms of androgens on disuse osteosarcopenia. Adult male mice received a unilateral botulinum toxin (BTx) injection, and underwent sham surgery or orchidectomy (ORX) without or with testosterone (ORX+T) or dihydrotestosterone (ORX+DHT) replacement. Compared to the contralateral internal control hindlimb, acute trabecular number and bone volume loss was increased by ORX and partially prevented DHT. T was more efficient and increased BV/TV in both hindlimbs over sham values, although it did not reduce the detrimental effect of BTx. Both androgens and BTx regulated trabecular osteoclast surface as well as tartrate-resistant acid phosphatase expression. Androgens also prevented BTx-induced body weight loss but did not significantly influence paralysis or muscle atrophy. BTx and ORX both reduced cortical thickness via endosteal expansion, which was prevented by T but not DHT. In long-term follow-up, the residual trabecular bone volume deficit in sham-BTx hindlimbs was prevented by DHT but T restored it more efficiently to pre-treatment levels. Conditional AR deletion in late osteoblasts and osteocytes or in the satellite cell lineage increased age-related trabecular bone loss in both hindlimbs without influencing the effect of BTx on trabecular osteopenia. We conclude that androgens have antiresorptive effects on trabecular disuse osteopenia which do not
Helsdingen, Richard J. R.; Hamers, Astrid R. M.; van Duursen, Majorie B. M.; Nielen, Michel W. F.; Hoogenboom, Ron L. A. P.
2007-01-01
Public concern about the presence of natural and anthropogenic compounds which affect human health by modulating normal endocrine functions is continuously growing. Fast and simple high-throughput screening methods for the detection of hormone activities are thus indispensable. During the last two decades, a panel of different in vitro assays has been developed, mainly for compounds with an estrogenic mode of action. Here we describe the development of an androgen transcription activation assay that is easy to use in routine screening. Recombinant yeast cells were constructed that express the human androgen receptor and yeast enhanced green fluorescent protein (yEGFP), the latter in response to androgens. Compared with other reporters, the yEGFP reporter protein is very convenient because it is directly measurable in intact living cells, i.e., cell wall disruption and the addition of a substrate are not needed. When yeast was exposed to 17β-testosterone, the concentration where half-maximal activation is reached (EC50) was 50 nM. The relative androgenic potencies, defined as the ratio between the EC50 of 17β-testosterone and the EC50 of the compound, of 5α-dihydrotestosterone, methyltrienolone, and 17β-boldenone are 2.3, 1.4, and 0.15 respectively. The results presented in this paper demonstrate that this new yeast androgen bioassay is fast, sensitive, and very specific and also suited to detect compounds that have an antiandrogenic mode of action. PMID:17849102
Grassi, S; Frondaroli, A; Di Mauro, M; Pettorossi, V E
2010-12-15
In brainstem slices of young male rat, we investigated the influence of the neuroactive steroid testosterone (T) on the synaptic responses by analyzing the field potential evoked in the medial vestibular nucleus (MVN) by vestibular afferent stimulation. T induced three distinct and independent long-term synaptic changes: fast long-lasting potentiation (fLP), slow long-lasting potentiation (sLP) and long-lasting depression (LD). The fLP was mediated by 17β-estradiol (E(2)) since it was abolished by blocking the estrogen receptors (ERs) or the enzyme converting T to E(2). Conversely, sLP and LD were mediated by 5α-dihydrotestosterone (DHT) since they were prevented by blocking the androgen receptors (ARs) or the enzyme converting T to DHT. Therefore, the synaptic effects of T were mediated by its androgenic or estrogenic metabolites. The pathways leading to estrogenic and androgenic conversion of T might be co-localized since, the occurrence of fLP under block of androgenic pathway, and that of sLP and LD under estrogenic block, were higher than those observed without blocks. In case of co-localization, the effect on synaptic transmission should depend on the prevailing enzymatic activity. We conclude that circulating and neuronal T can remarkably influence synaptic responses of the vestibular neurons in different and opposite ways, depending on its conversion to estrogenic or androgenic metabolites. Copyright © 2010 IBRO. Published by Elsevier Ltd. All rights reserved.
Pop, Anca; Drugan, Tudor; Gutleb, Arno C; Lupu, Diana; Cherfan, Julien; Loghin, Felicia; Kiss, Béla
2016-04-01
The individual and combined (binary mixtures) (anti)androgenic effect of butylparaben (BuPB), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and propyl gallate (PG) was evaluated using the MDA-kb2 cell line. Exposing these cells to AR agonists results in the expression of the reporter gene (encoding for luciferase) and luminescence can be measured in order to monitor the activity of the reporter protein. In case of the evaluation of the anti-androgenic effect, the individual test compounds or binary mixtures were tested in the presence of a fixed concentration of a strong AR agonist (1000 pM 5-alpha-dihydrotestosterone; DHT). Cell viability was assessed using a resazurin based assay. For PG, this is the first report in the literature concerning its (anti)androgenic activity. In case of both individual and mixture testing none of the compounds or binary combinations showed androgenic activity. When tested in the presence of DHT, BuPB, BHA and BHT proved to be weak anti-androgens and this was confirmed during the evaluation of binary mixtures (BuPB+BHA, BuPB+BHT and BHA+BHT). Besides performing the in vitro testing of the binary combinations, two mathematical models (dose addition and response addition) were evaluated in terms of accuracy of prediction of the anti-androgenic effect of the selected binary mixtures. The dose addition model guaranteed a good correlation between the experimental and predicted data. However, no estimation was possible in case of mixtures containing PG, due to the lack of effect of the compound in case of the individual testing. Copyright © 2016 Elsevier Ltd. All rights reserved.
Sulforaphane promotes murine hair growth by accelerating the degradation of dihydrotestosterone.
Sasaki, Mari; Shinozaki, Shohei; Shimokado, Kentaro
2016-03-25
Dihydrotestosterone (DHT) causes the regression of human hair follicles in the parietal scalp, leading to androgenic alopecia (AGA). Sulforaphane (SFN) increases the expression of DHT degrading enzymes, such as 3α-hydroxysteroid dehydrogenases (3α-HSDs), and, therefore, SFN treatment may improve AGA. To determine the effects of SFN on hair growth, we administered SFN (10 mg/kg BW, IP) or vehicle (DMSO) to ob/ob mice for six weeks and examined hair regeneration and the plasma levels of testosterone and DHT. We also tested the effects of SFN on the expression of two forms of 3α-HSD, aldo-keto reductase 1c21 and dehydrogenase/reductase (SDR family) member 9, both in vitro and in vivo. SNF significantly enhanced hair regeneration in ob/ob mice. The mice treated with SFN showed lower plasma levels of testosterone and DHT than those treated with vehicle. SFN increased the mRNA and protein levels of the two forms of 3α-HSD in the liver of the mice and in cultured murine hepatocyte Hepa1c1c7 cells. These results suggest that SFN treatment increases the amount of 3α-HSDs in the liver, accelerates the degradation of blood DHT, and subsequently blocks the suppression of hair growth by DHT. Copyright © 2016 Elsevier Inc. All rights reserved.
Mizutani, Naoki; Inoue, Minami; Omori, Yukari; Ito, Hiromi; Tamiya-Koizumi, Keiko; Takagi, Akira; Kojima, Tetsuhito; Nakamura, Mitsuhiro; Iwaki, Soichiro; Nakatochi, Masahiro; Suzuki, Motoshi; Nozawa, Yoshinori; Murate, Takashi
2015-10-01
Acid ceramidase (ACDase) metabolizes ceramide to sphingosine, leading to sphingosine 1-phosphate production. Reportedly, ACDase has been upregulated in prostate cancer. However, its regulatory mechanism remains unclear. LNCaP (androgen-sensitive prostate cancer cell line) but not PC3 and DU-145, (androgen-unresponsive cell lines) exhibited the highest ACDase protein. Among three cell lines, ASAH1 mRNA level was not correlated with ACDase protein expression, and the 5'-promoter activity did not show androgen dependency, suggesting the post-transcriptional regulation of ACDase in LNCaP cells. Based on these results, LNCaP was analysed further. Casodex, androgen receptor antagonist, and charcoal-stripped FCS (CS-FCS) decreased ACDase protein and activity, whereas dihydrotestosterone in CS-FCS culture increased ACDase protein and enzyme activity. MG132, a proteasome inhibitor, prevented the decrease of ACDase protein when cultured in CS-FCS, suggesting the involvement of ubiquitin/proteasome system. Reportedly, USP2, a deubiquitinase, plays an important role in LNCaP cells. USP2 siRNA decreased ACDase protein, whereas USP2 overexpression increased ACDase protein of LNCaP cells. However, SKP2, an ubiquitin E3 ligase known to be active in prostate cancer, did not affect androgen-dependent ACDase expression in LNCaP cells. Thus, ACDase regulation by androgen in androgen-sensitive LNCaP cells is mainly due to its prolonged protein half-life by androgen-stimulated USP2 expression. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.
Fukami, Maki; Homma, Keiko; Hasegawa, Tomonobu; Ogata, Tsutomu
2013-04-01
We review the current knowledge about the "backdoor" pathway for the biosynthesis of dihydrotestosterone (DHT). While DHT is produced from cholesterol through the conventional "frontdoor" pathway via testosterone, recent studies have provided compelling evidence for the presence of an alternative "backdoor" pathway to DHT without testosterone intermediacy. This backdoor pathway is known to exist in the tammar wallaby pouch young testis and the immature mouse testis, and has been suggested to be present in the human as well. Indeed, molecular analysis has identified pathologic mutations of genes involved in the backdoor pathway in genetic male patients with undermasculinized external genitalia, and urine steroid profile analysis has argued for the relevance of the activated backdoor pathway to abnormal virilization in genetic females with cytochrome P450 oxidoreductase deficiency and 21-hydroxylase deficiency. It is likely that the backdoor pathway is primarily operating in the fetal testis in a physiological condition to produce a sufficient amount of DHT for male sex development, and that the backdoor pathway is driven with a possible interaction between fetal and permanent adrenals in pathologic conditions with increased 17-hydroxyprogesterone levels. These findings provide novel insights into androgen biosynthesis in both physiological and pathological conditions. Copyright © 2012 Wiley Periodicals, Inc., a Wiley company.
The preclinical biology of a new potent and selective progestin: trimegestone.
Winneker, Richard C; Bitran, Daniel; Zhang, Zhiming
2003-11-01
Trimegestone (TMG) is a 19-norpregnane progestin being developed, in combination with an estrogen, for the treatment of postmenopausal symptoms. TMG binds to the human progesterone receptor with an affinity greater than medroxyprogesterone acetate (MPA), norethindrone (NET), and levonorgestrel (LNG). In contrast, TMG binds with low affinity to the androgen, glucocorticoid and mineralocorticoid receptor and has no measurable affinity for the estrogen receptor. Compared to other progestins, TMG demonstrates an improved separation of its PR affinity from its affinity to other classical steroid hormone receptors. In vivo, TMG has potent progestin activity. For example, TMG produces glandular differentiation of the uterine endometrium in rabbits and is about 30 and 60 times more potent than MPA and NET, respectively. In the rat, TMG maintains pregnancy, induces deciduoma formation, inhibits ovulation and has uterine anti-estrogenic activity. With respect to these endpoints, TMG appears to be more potent and selective on uterine epithelial responses than other classical progestin responses. In vivo, TMG does not have significant androgenic, glucocorticoid, anti-glucocorticoid or mineralocorticoid activity but does have anti-mineralocorticoid activity and modest anti-androgenic effects. This overall profile is qualitatively similar to progesterone. When TMG is administered chronically, it antagonizes the effect of estradiol on the uterus but does not antagonize the beneficial bone sparing activity of estradiol. In rat studies evaluating CNS GABAA receptor modulatory activity, TMG is less active on this likely undesirable endpoint than progesterone and norethindrone acetate, which may translate into fewer mood-related side effects. The results indicate that TMG is a potent and selective progestin with a preclinical profile well suited for hormone replacement therapy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kloosterboer, H.J.; Vonk-Noordegraaf, C.A.; Turpijn, E.W.
1988-09-01
The relative binding affinities (RBAs) of four progestational compounds (norethisterone, levonorgestrel, 3-keto-desogestrel and gestodene) for the human progesterone and androgen receptors were measured in MCF-7 cytosol and intact MCF-7 cells. For the binding to the progesterone receptor, both Org 2058 and Org 3236 (or 3-keto-desogestrel) were used as labelled ligands. The following ranking (low to high) for the RBA of the nuclear (intact cells) progesterone receptor irrespective of the ligand used is found: norethisterone much less than levonorgestrel less than 3-keto-destogestrel less than gestodene. The difference between the various progestagens is significant with the exception of that between 3-keto-desogestrel andmore » gestodene, when Org 2058 is used as ligand. For the cytosolic progesterone receptor, the same order is found with the exception that similar RBAs are found for gestodene and 3-keto-desogestrel. The four progestagens clearly differ with respect to binding to the androgen receptor using dihydrotestosterone as labelled ligand in intact cells; the ranking (low to high) is: norethisterone less than 3 keto-desogestrel less than levonorgestrel and gestodene. The difference between 3-keto-desogestrel and levonorgestrel or gestodene is significant. The selectivity indices (ratio of the mean RBA for the progesterone receptor to that of androgen receptor) in intact cells are significantly higher for 3-keto-desogestrel and gestodene than for levonorgestrel and norethisterone. From these results we conclude that the introduction of the 18-methyl in norethisterone (levonorgestel) increases both the binding to the progesterone and androgen receptors.« less
Baculescu, N
2013-03-15
Polycystic ovary syndrome (PCOS), one of the most common and complex endocrine disorders affecting up to 15 % of reproductive age women, is considered a predominantly hyperandrogenic syndrome according to the Androgen Excess Society. It is generally accepted that androgens determine the characteristic features of PCOS; in this context, a hyperactive androgen receptor (AR) at the levels of the GnRH pulse generator in the hypothalamus and at the granulosa cells in the ovary, skeletal muscle or adipocytes senses initially normal testosterone and dihydrotestosterone as biochemical hyperandrogenism and might be a crucial connection between the vicious circles of the PCOS pathogenesis. Polymorphism of the AR gene has been associated with different androgen pattern diseases. Several studies have demonstrated an association between AR with increased activity encoded by shorter CAG repeat polymorphism in the exon 1 of the AR gene and PCOS, although there are conflicting results in this field. The phenomenon is more complex because the AR activity is determined by the epigenetic effect of X chromosome inactivation (XCI). Moreover, we must evaluate the AR as a dynamic heterocomplex, with a large number of coactivators and corepressors that are essential to its function, thus mediating tissue-specific effects. In theory, any of these factors could modify the activity of AR, which likely explains the inconsistent results obtained when this activity was quantified by only the CAG polymorphism in PCOS.
Narayanan, Ramesh; Coss, Christopher C; Yepuru, Muralimohan; Kearbey, Jeffrey D; Miller, Duane D; Dalton, James T
2008-11-01
Androgen receptor (AR) ligands are important for the development and function of several tissues and organs. However, the poor oral bioavailability, pharmacokinetic properties, and receptor cross-reactivity of testosterone, coupled with side effects, place limits on its clinical use. Selective AR modulators (SARMs) elicit anabolic effects in muscle and bone, sparing reproductive organs like the prostate. However, molecular mechanisms underlying the tissue selectivity remain ambiguous. We performed a variety of in vitro studies to compare and define the molecular mechanisms of an aryl propionamide SARM, S-22, as compared with dihydrotestosterone (DHT). Studies indicated that S-22 increased levator ani muscle weight but decreased the size of prostate in rats. Analysis of the upstream intracellular signaling events indicated that S-22 and DHT mediated their actions through distinct pathways. Modulation of these pathways altered the recruitment of AR and its cofactors to the PSA enhancer in a ligand-dependent fashion. In addition, S-22 induced Xenopus laevis oocyte maturation and rapid phosphorylation of several kinases, through pathways distinct from steroids. These studies reveal novel differences in the molecular mechanisms by which S-22, a nonsteroidal SARM, and DHT mediate their pharmacological effects.
Regulation of uterine progesterone receptors by the nonsteroidal anti-androgen hydroxyflutamide
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chandrasekhar, Y.; Armstrong, D.T.
1991-07-01
The authors have recently reported that the anti-androgen hydroxyflutamide causes delayed implantation and exhibits antideciduogenic activity in the rat. The present experiments were conducted to examine whether hydroxyflutamide binds to the uterine progesterone receptors and/or alters the progesterone binding sites in the uterus. Cytosol and nuclear fractions from decidualized rat uterus were incubated with (3H)-R5020 without or with increasing concentrations of radioinert R5020, RU486, dihydrotestosterone, or hydroxyflutamide. From the log-dose inhibition curves, the relative binding affinity of both hydroxyflutamide and dihydrotestosterone was less than 0.1% and 2%, compared with R5020 (100%) for displacing (3H)-R5020 bound to uterine cytosol and nuclearmore » fractions, respectively. Injection of estradiol-17 beta (1 microgram/rat) to ovariectomized prepubertal rats induced a 1.85-fold increase in uterine weight by 24 h. Hydroxyflutamide at 2.5 or 5.0 mg did not significantly alter the estrogen-induced increase in uterine weight. Compared to vehicle alone, estrogen induced an approximately 5-fold increase in uterine cytosolic progesterone binding sites. Hydroxyflutamide at both 2.5- and 5.0-mg doses significantly attenuated the estrogen-induced elevation in uterine progesterone binding sites. These studies demonstrate that hydroxyflutamide does not bind with high affinity to progesterone receptors, but suppresses the estrogen-induced elevation in progesterone receptor levels in the uterus.« less
Gonzales, Rayna J; Ansar, Saema; Duckles, Sue P; Krause, Diana N
2008-01-01
Tissues from males can be regulated by a balance of androgenic and estrogenic effects because of local metabolism of testosterone and expression of relevant steroid hormone receptors. As a critical first step to understanding sex hormone influences in the cerebral circulation of males, we investigated the presence of enzymes that metabolize testosterone to active products and their respective receptors. We found that cerebral blood vessels from male rats express 5α-reductase type 2 and aromatase, enzymes responsible for conversion of testosterone into dihydrotestosterone (DHT) and 17β-estradiol, respectively. Protein levels of these enzymes, however, were not modulated by long-term in vivo hormone treatment. We also showed the presence of receptors for both androgens (AR) and estrogens (ER) from male cerebral vessels. Western blot analysis showed bands corresponding to the full-length AR (110 kDa) and ERα (66 kDa). Long-term in vivo treatment of orchiectomized rats with testosterone or DHT, but not estrogen, increased AR levels in cerebral vessels. In contrast, ERα protein levels were increased after in vivo treatment with estrogen but not testosterone. Fluorescent immunostaining revealed ERα, AR, and 5α-reductase type 2 in both the endothelial and smooth muscle layers of cerebral arteries, whereas aromatase staining was solely localized to the endothelium. Thus, cerebral vessels from males are target tissues for both androgens and estrogen. Furthermore, local metabolism of testosterone might balance opposing androgenic and estrogenic influences on cerebrovascular as well as brain function in males. PMID:17406656
Smith, Peter; Steckler, Teresa L; Veiga-Lopez, Almudena; Padmanabhan, Vasantha
2009-04-01
Prenatal testosterone excess programs an array of adult reproductive disorders including luteinizing hormone excess, functional hyperandrogenism, neuroendocrine defects, polycystic ovarian morphology, and corpus luteum dysfunction, culminating in early reproductive failure. Polycystic ovarian morphology originates from enhanced follicular recruitment and follicular persistence. We tested to determine whether prenatal testosterone treatment, by its androgenic actions, enhances follicular recruitment, causes early depletion of follicular reserve, and disrupts the ovarian architecture. Pregnant sheep were given twice-weekly injections of testosterone or dihydrotestosterone (DHT), a nonaromatizable androgen, from Days 30 to 90 of gestation. Ovaries were obtained from Day-90 and Day-140 fetuses, and from 10-mo-old females during a synchronized follicular phase (n = 5-9 per treatment). Stereological techniques were used to quantify changes in ovarian follicle/germ cell populations. Results revealed no differences in numbers of oocytes and follicles between the three groups on Fetal Day 90. Greater numbers of early growing follicles were found in prenatal testosterone- and DHT-treated fetuses on Day 140. Increased numbers of growing follicles and reduced numbers of primordial follicles were found in 10-mo-old, prenatal testosterone-treated females, but not in those treated with DHT. Antral follicles of prenatal testosterone-treated females, but not those treated with DHT, manifested several abnormalities, which included the appearance of hemorrhagic and luteinized follicles and abnormal early antrum formation. Both treatment groups showed morphological differences in the rete ovarii. These findings suggest that increased follicular recruitment and morphologic changes in the rete ovarii of prenatal testosterone-treated females are facilitated by androgenic programming, but that postpubertal follicular growth, antral follicular disruptions, and follicular depletion largely
Laird, Mhairi; Thomson, Kacie; Fenwick, Mark; Mora, Jocelyn; Hardy, Kate
2017-01-01
Androgens are essential for the normal function of mature antral follicles but also have a role in the early stages of follicle development. Polycystic ovary syndrome (PCOS), the most common cause of anovulatory infertility, is characterized by androgen excess and aberrant follicle development that includes accelerated early follicle growth. We have examined the effects of testosterone and dihydrotestosterone (DHT) on development of isolated mouse preantral follicles in culture with the specific aim of investigating interaction with follicle-stimulating hormone (FSH), the steroidogenic pathway, and growth factors of the TGFβ superfamily that are known to have a role in early follicle development. Both testosterone and DHT stimulated follicle growth and augmented FSH-induced growth and increased the incidence of antrum formation among the granulosa cell layers of these preantral follicles after 72 hours in culture. Effects of both androgens were reversed by the androgen receptor antagonist flutamide. FSH receptor expression was increased in response to both testosterone and DHT, as was that of Star, whereas Cyp11a1 was down-regulated. The key androgen-induced changes in the TGFβ signaling pathway were down-regulation of Amh, Bmp15, and their receptors. Inhibition of Alk6 (Bmpr1b), a putative partner for Amhr2 and Bmpr2, by dorsomorphin resulted in augmentation of androgen-stimulated growth and modification of androgen-induced gene expression. Our findings point to varied effects of androgen on preantral follicle growth and function, including interaction with FSH-activated growth and steroidogenesis, and, importantly, implicate the intrafollicular TGFβ system as a key mediator of androgen action. These findings provide insight into abnormal early follicle development in PCOS. PMID:28324051
Laird, Mhairi; Thomson, Kacie; Fenwick, Mark; Mora, Jocelyn; Franks, Stephen; Hardy, Kate
2017-04-01
Androgens are essential for the normal function of mature antral follicles but also have a role in the early stages of follicle development. Polycystic ovary syndrome (PCOS), the most common cause of anovulatory infertility, is characterized by androgen excess and aberrant follicle development that includes accelerated early follicle growth. We have examined the effects of testosterone and dihydrotestosterone (DHT) on development of isolated mouse preantral follicles in culture with the specific aim of investigating interaction with follicle-stimulating hormone (FSH), the steroidogenic pathway, and growth factors of the TGFβ superfamily that are known to have a role in early follicle development. Both testosterone and DHT stimulated follicle growth and augmented FSH-induced growth and increased the incidence of antrum formation among the granulosa cell layers of these preantral follicles after 72 hours in culture. Effects of both androgens were reversed by the androgen receptor antagonist flutamide. FSH receptor expression was increased in response to both testosterone and DHT, as was that of Star, whereas Cyp11a1 was down-regulated. The key androgen-induced changes in the TGFβ signaling pathway were down-regulation of Amh, Bmp15, and their receptors. Inhibition of Alk6 (Bmpr1b), a putative partner for Amhr2 and Bmpr2, by dorsomorphin resulted in augmentation of androgen-stimulated growth and modification of androgen-induced gene expression. Our findings point to varied effects of androgen on preantral follicle growth and function, including interaction with FSH-activated growth and steroidogenesis, and, importantly, implicate the intrafollicular TGFβ system as a key mediator of androgen action. These findings provide insight into abnormal early follicle development in PCOS.
Jain, Ruchy; Monthakantirat, Orawan; Tengamnuay, Parkpoom; De-Eknamkul, Wanchai
2016-01-21
Androgenic alopecia (AGA) is a major type of human scalp hair loss, which is caused by two androgens: testosterone (T) and 5α-dihydrotestosterone (5α-DHT). Both androgens bind to the androgen receptor (AR) and induce androgen-sensitive genes within the human hair dermal papilla cells (HHDPCs), but 5α-DHT exhibits much higher binding affinity and potency than T does in inducing the involved androgen-sensitive genes. Changes in the induction of androgen-sensitive genes during AGA are caused by the over-production of 5α-DHT by the 5α-reductase (5α-R) enzyme; therefore, one possible method to treat AGA is to inhibit this enzymatic reaction. RT-PCR was used to identify the presence of the 5α-R and AR within HHDPCs. A newly developed AGA-relevant HHDPC-based assay combined with non-radioactive thin layer chromatography (TLC) detection was used for screening crude plant extracts for the identification of new 5α-R inhibitors. HHDPCs expressed both 5α-R type 1 isoform of the enzyme (5α-R1) and AR in all of the passages used in this study. Among the thirty tested extracts, Avicennia marina (AM) displayed the highest inhibitory activity at the final concentration of 10 μg/ml, as the production of 5α-DHT decreased by 52% (IC50 = 9.21 ± 0.38 μg/ml). Avicennia marina (AM) was identified as a potential candidate for the treatment of AGA based on its 5α-R1-inhibitory activity.
Prenatal androgen excess programs metabolic derangements in pubertal female rats.
Yan, Xiaonan; Dai, Xiaonan; Wang, Jing; Zhao, Nannan; Cui, Yugui; Liu, Jiayin
2013-04-01
Owing to the heterogeneity in the clinical symptoms of polycystic ovary syndrome (PCOS), the early pathophysiological mechanisms of PCOS remain unclear. Clinical, experimental, and genetic evidence supports an interaction between genetic susceptibility and the influence of maternal environment in the pathogenesis of PCOS. To determine whether prenatal androgen exposure induced PCOS-related metabolic derangements during pubertal development, we administrated 5α-dihydrotestosterone (DHT) in pregnant rats and observed their female offspring from postnatal 4 to 8 weeks. The prenatally androgenized (PNA) rats exhibited more numerous total follicles, cystic follicles, and atretic follicles than the controls. Fasting glucose, insulin, leptin levels, and homeostatic model assessment for insulin resistance were elevated in the PNA rats at the age of 5-8 weeks. Following intraperitoneal glucose tolerance tests, glucose and insulin levels did not differ between two groups; however, the PNA rats showed significantly higher 30- and 60-min glucose levels than the controls after insulin stimulation during 5-8 weeks. In addition, prenatal DHT treatment significantly decreased insulin-stimulated phosphorylation of AKT in the skeletal muscles of 6-week-old PNA rats. The abundance of IR substrate 1 (IRS1) and IRS2 was decreased in the skeletal muscles and liver after stimulation with insulin in the PNA group, whereas phosphorylation of insulin-signaling proteins was unaltered in the adipose tissue. These findings validate the contribution of prenatal androgen excess to metabolic derangements in pubertal female rats, and the impaired insulin signaling through IRS and AKT may result in the peripheral insulin resistance during pubertal development.
Zou, Qingsong; Cui, Di; Liang, Shengjie; Xia, Shujie; Jing, Yifeng; Han, Bangmin
2016-06-01
Stromal cells in the peripheral zone (PZ) of the prostate from older males (PZ-old) could significantly promote Prostate cancer (PCa) growth compared with stromal cells from young males (PZ-young). But the mechanism is still unknown. In the co-culture system with PZ-old cells, Pc3/Du145 cells showed advanced proliferation and migration after Dihydrotestosterone (DHT) incubation, but DHT didn't show the similar effect in PZ-young co-culture system. Also, higher androgen/AR signal pathway activity and AR-related cytokines secretion (FGF-2, KGF, IGF-1) were found in PZ-old cells. As AR exprssison was equivalent in PZ-old and PZ-young cells, we focused on Androgen receptor associated protein-55(ARA55), a stromal-specific androgen receptor (AR) coactivator. ARA55 expression was higher in PZ-old cells compared with PZ-young cells in vitro. After knocking down ARA55 expression in PZ-old cells, the PCa growth- promoting effect from the PZ-old cells was diminished, which may be explained by the decreased the progressive cytokines secretion (FGF-2, KGF, IGF-1) from PZ-old stromal cells. In vivo, the consistent results were also found: PZ-old cells promoted prostate cancer cells growth, but this effect receded when knocking down ARA55 expression in PZ-old cells. From our study, we found PZ stromal cells presented age-related effects in proliferation and migration of prostate cancer cells in the androgen/AR dependent manner. As aging increased, more ARA55 were expressed in PZ stromal cells, leading to more sensitive androgen/androgen receptor (AR) signal pathway, then constituting a more feasible environment to cancer cells.
Liu, Shan; Ying, Guang-Guo; Zhao, Jian-Liang; Zhou, Li-Jun; Yang, Bin; Chen, Zhi-Feng; Lai, Hua-Jie
2012-02-01
The occurrence and fate of fourteen androgens, four estrogens, five glucocorticoids and five progestagens were investigated in two different types of wastewater treatment plants (Plant A: activated sludge with chlorination, and Plant B: oxidation ditch with UV) of Guangdong province, China. 14, 14, and 10 of 28 target compounds were detected in the influent, effluent and dewatered sludge samples with the concentrations ranging from below 1.2 ± 0.0 ng L(-1) (stanozolol) to 1368 ± 283 ng L(-1) (epi-androsterone), below 1.0 ± 0.0 ng L(-1) (progesterone) to 23.1 ± 1.0 ng L(-1) (5α-dihydrotestosterone), 1.0 ± 0.1 ng g(-1) (estrone) to 460 ± 4.4 ng g(-1) (5α-dihydrotestosterone), respectively. The concentrations of total androgens (1554-1778 ng L(-1) in influent, 13.3-47.8 ng L(-1) in effluent, 377-923 ng g(-1) in dewatered sludge) were much higher than those of total estrogens (41.5-60.2 ng L(-1) in influent, 5.6-13.5 ng L(-1) in effluent, 13.9-57.8 ng g(-1) in dewatered sludge), glucocorticoids (171-192 ng L(-1) in influent, 2.2-6.3 ng L(-1) in effluent, N.D.-4.4 ng g(-1) in dewatered sludge), and progestagens (39.6-40.5 ng L(-1) in influent, 6.9-12.1 ng L(-1) in effluent, N.D. in dewatered sludge) in these two WWTPs. According to mass balance analysis, the removal rates of most target steroids in Plant A had exceeded 90%, while those in Plant B for nearly half of detected target steroids were lower than 80%. It is obvious that the treatment capacity of the activated sludge system (Plant A) is superior to the oxidation ditch (Plant B) in the degradation of steroids in sewage treatment systems. Androgens, estrogens and progestagens were mainly removed by sorption and degradation, while the reduction of glucocorticoids was primarily due to degradation.
Manti, Maria; Fornes, Romina; Qi, Xiaojuan; Folmerz, Elin; Lindén Hirschberg, Angelica; de Castro Barbosa, Thais; Maliqueo, Manuel; Benrick, Anna; Stener-Victorin, Elisabet
2018-03-22
Maternal polycystic ovary syndrome (PCOS), a condition associated with hyperandrogenism, is suggested to increase anxiety-like behavior in the offspring. Because PCOS is closely linked to obesity, we investigated the impact of an adverse hormonal or metabolic maternal environment and offspring obesity on anxiety in the offspring. The obese PCOS phenotype was induced by chronic high-fat-high-sucrose (HFHS) consumption together with prenatal dihydrotestosterone exposure in mouse dams. Anxiety-like behavior was assessed in adult offspring with the elevated-plus maze and open-field tests. The influence of maternal androgens and maternal and offspring diet on genes implicated in anxiety were analyzed in the amygdala and hypothalamus with real-time PCR ( n = 47). Independent of diet, female offspring exposed to maternal androgens were more anxious and displayed up-regulation of adrenoceptor α 1B in the amygdala and up-regulation of hypothalamic corticotropin-releasing hormone ( Crh). By contrast, male offspring exposed to a HFHS maternal diet had increased anxiety-like behavior and showed up-regulation of epigenetic markers in the amygdala and up-regulation of hypothalamic Crh. Overall, there were substantial sex differences in gene expression in the brain. These findings provide novel insight into how maternal androgens and obesity exert sex-specific effects on behavior and gene expression in the offspring of a PCOS mouse model.-Manti, M., Fornes, R., Qi, X., Folmerz, E., Lindén Hirschberg, A., de Castro Barbosa, T., Maliqueo, M., Benrick, A., Stener-Victorin, E. Maternal androgen excess and obesity induce sexually dimorphic anxiety-like behavior in the offspring.
Nejishima, Hiroaki; Yamamoto, Noriko; Suzuki, Mika; Furuya, Kazuyuki; Nagata, Naoya; Yamada, Shizuo
2012-10-01
Selective androgen receptor modulators (SARMs) would provide alternative therapeutic agent for androgen-related diseases. We identified a tetrahydroquinoline (THQ) derivative, 1-(8-nitro-3a, 4, 5, 9b-tetrahydro-3H-cyclopenta[c]quinolin-4-yl) ethane-1, 2-diol (S-40542) as a novel SARM antagonist. Affinity for nuclear receptors of S-40542 was evaluated in receptor-binding studies. Androgen receptor (AR) transcriptional activity of S-40542 was investigated by luciferase reporter assay in DU145AR cells. Normal and benign prostatic hyperplasia (BPH) model rats were repeatedly treated with S-40542 and flutamide. The tissue weights of prostate and levator ani muscle as well as blood levels of testosterone and luteinizing hormone were measured. S-40542 bound to the AR with high affinity. S-40542 at relatively high concentrations increased the transcriptional activity. This agent also showed a concentration-dependent AR antagonistic action in the presence of 1 nM 5α-dihydrotestosterone. Repeated treatment with S-40542 and flutamide decreased dose-dependently the weights of the prostate to a similar extent. In contrast, the tissue weight-reducing effect by S-40542 treatment on the levator ani muscle was much weaker than that of flutamide. S-40542 had little effect on the blood level of testosterone and luteinizing hormone, whereas flutamide increased the level of both hormones. Furthermore, S-40542 decreased dose-dependently prostate weight of BPH rats. The current results indicate that S-40542 possesses the prostate-selective SARM activity, suggestive of clinical benefit against benign prostate hyperplasia. THQ compounds may be useful for the research of mode of action of SARMs and for the development of safe SARM antagonists. Copyright © 2012 Wiley Periodicals, Inc.
Veiga-Lopez, A; Wurst, A K; Steckler, T L; Ye, W; Padmanabhan, V
2014-04-01
Excess of prenatal testosterone (T) induces reproductive defects including follicular persistence. Comparative studies with T and dihydrotestosterone (DHT) have suggested that follicular persistence is programmed via estrogenic actions of T. This study addresses the androgenic and estrogenic contributions in programming follicular persistence. Because humans are exposed to estrogenic environmental steroids from various sources throughout their life span and postnatal insults may also induce organizational and/or activational changes, we tested whether continuous postnatal exposure to estradiol (E) will amplify effects of prenatal steroids on ovarian function. Pregnant sheep were treated with T, DHT, E, or ED (E and DHT) from days 30 to 90 of gestation. Postnatally, a subset of the vehicle (C), T, and DHT females received an E implant. Transrectal ultrasonography was performed in the first breeding season during a synchronized cycle to monitor ovarian follicular dynamics. As expected, number of ≥8 mm follicles was higher in the T versus C group. Postnatal E reduced the number of 4 to 8 mm follicles in the DHT group. Percentage of females bearing luteinized follicles and the number of luteinized follicles differed among prenatal groups. Postnatal E increased the incidence of subluteal cycles in the prenatal T-treated females. Findings from this study confirm previous findings of divergences in programming effects of prenatal androgens and estrogens. They also indicate that some aspects of follicular dynamics are subject to postnatal modulation as well as support the existence of an extended organizational period or the need for a second insult to uncover the previously programmed event.
Veiga-Lopez, Almudena; Astapova, Olga I; Aizenberg, Esther F; Lee, James S; Padmanabhan, Vasantha
2009-04-01
Prenatal testosterone excess leads to neuroendocrine and periovulatory disruptions in the offspring culminating in progressive loss of cyclicity. It is unknown whether the mediary of these disruptions is androgen or estrogen, because testosterone can be aromatized to estrogen. Taking a reproductive life span approach of studying control, prenatal testosterone, and dihydrotestosterone-treated offspring, this study tested the hypothesis that disruptions in estradiol-negative but not -positive feedback effects are programmed by androgenic actions of testosterone and that these disruptions in turn will have an impact on the periovulatory hormonal dynamics. The approach was to test estradiol-negative and -positive feedback responses of all three groups of ovary-intact females during prepubertal age and then compare the periovulatory dynamics of luteinizing hormone, follicle-stimulating hormone, estradiol, and progesterone during the first breeding season. The findings show that estradiol-negative but not estradiol-positive feedback disruptions in prenatal testosterone-treated females are programmed by androgenic actions of prenatal testosterone excess and that follicular phase estradiol and gonadotropins surge disruptions during reproductive life are consistent with estrogenic programming. Additional studies carried out testing estradiol-positive feedback response over time found progressive deterioration of estradiol-positive feedback in prenatal testosterone-treated sheep until the time of puberty. Together, these findings provide insight into the mechanisms by which prenatal testosterone disrupts the reproductive axis. The findings may be of translational relevance since daughters of mothers with hyperandrogenism are at risk of increased exposure to androgens.
Fornes, Romina; Maliqueo, Manuel; Hu, Min; Hadi, Laila; Jimenez-Andrade, Juan M; Ebefors, Kerstin; Nyström, Jenny; Labrie, Fernand; Jansson, Thomas; Benrick, Anna; Stener-Victorin, Elisabet
2017-08-14
Pregnant women with polycystic ovary syndrome (PCOS) are often overweight or obese. To study the effects of maternal androgen excess in obese dams on metabolism, placental function and fetal growth, female C57Bl6J mice were fed a control (CD) or a high fat/high sucrose (HF/HS) diet for 4-10 weeks, and then mated. On gestational day (GD) 15.5-17.5, dams were injected with dihydrotestosterone (CD-DHT, HF/HS-DHT) or a vehicle (CD-Veh, HF/HS-Veh). HF/HS dams had higher fat content, both before mating and on GD18.5, with no difference in glucose homeostasis, whereas the insulin sensitivity was higher in DHT-exposed dams. Compared to the CD groups, the livers from HF/HS dams weighed more on GD18.5, the triglyceride content was higher, and there was a dysregulation of liver enzymes related to lipogenesis and higher mRNA expression of Fitm1. Fetuses from HF/HS-Veh dams had lower liver triglyceride content and mRNA expression of Srebf1c. Maternal DHT exposure, regardless of diet, decreased fetal liver Pparg mRNA expression and increased placental androgen receptor protein expression. Maternal diet-induced obesity, together with androgen excess, affects maternal and fetal liver function as demonstrated by increased triglyceride content and dysfunctional expression of enzymes and transcription factors involved in de novo lipogenesis and fat storage.
Mezzetti, G; Loor, R; Liao, S
1979-01-01
The rat ventral prostate contains a cytosol protein that can non-covalently bind spermine much more tightly than spermidine or other natural diamines. The protein has been purified to homogeneity, as judged by electrophoresis in urea- and sodium dodecyl sulphate-containing polyacrylamide gels. The protein, with or without spermine bound to it, sediments at 3 S in a sucrose gradient with or without 0.4 M-KCl. The molecular weight of the protein is about 30 000. Each molecule of the binding protein can bind one molecule of spermine. In the prostate of rats injected with cycloheximide, the protein appears to have a half-life of about 3.5 h. The spermine-binding activity of an acidic fraction obtained by DEAE-cellulose chromatography of the prostate cytosol proteins is reduced by about 40--60% within 20--40 h after castration. This effect is reversed very rapidly within 15--30 min by intraperitoneal injection of 5 alpha-dihydrotestosterone. The hormonal effect is androgen-specific and is not mimicked by dexamethasone or oestradiol-17 beta. The androgen effect was reduced significantly when rats were injected with cycloheximide or actinomycin D, suggesting that the acidic protein may be one of the earliest proteins induced by androgen in the rat ventral prostate. Images Fig. 1. PMID:534539
Bhattacharyya, Rumi S; Krishnan, Aruna V; Swami, Srilatha; Feldman, David
2006-06-01
The androgen receptor (AR) plays a key role in the development and progression of prostate cancer. Targeting the AR for down-regulation would be a useful strategy for treating prostate cancer, especially hormone-refractory or androgen-independent prostate cancer. In the present study, we showed that the antiestrogen fulvestrant [ICI 182,780 (ICI)] effectively suppressed AR expression in several human prostate cancer cells, including androgen-independent cells. In LNCaP cells, ICI (10 micromol/L) treatment decreased AR mRNA expression by 43% after 24 hours and AR protein expression by approximately 50% after 48 hours. We further examined the mechanism of AR down-regulation by ICI in LNCaP cells. ICI did not bind to the T877A-mutant AR present in the LNCaP cells nor did it promote proteasomal degradation of the AR. ICI did not affect AR mRNA or protein half-life. However, ICI decreased the activity of an AR promoter-luciferase reporter plasmid transfected into LNCaP cells, suggesting a direct repression of AR gene transcription. As a result of AR down-regulation by ICI, androgen induction of prostate-specific antigen mRNA and protein expression were substantially attenuated. Importantly, LNCaP cell proliferation was significantly inhibited by ICI treatment. Following 6 days of ICI treatment, a 70% growth inhibition was seen in androgen-stimulated LNCaP cells. These data show that the antiestrogen ICI is a potent AR down-regulator that causes significant inhibition of prostate cancer cell growth. Our study suggests that AR down-regulation by ICI would be an effective strategy for the treatment of all prostate cancer, especially AR-dependent androgen-independent prostate cancer.
Hamada, K; Thornton, M J; Laing, I; Messenger, A G; Randall, V A
1996-05-01
Androgens regulate the growth of many human hair follicles, but only pubic, axillary, and scalp hair growth occur in men with 5 alpha-reductase deficiency. This suggests that 5 alpha-dihydrotestosterone is the active intracellular androgen in androgen-dependent follicles, except in the axilla and pubis. Since the dermal papilla plays a major regulatory role in hair follicles and may be the site of androgen action, we have investigated androgen metabolism in six primary lines of cultured dermal papilla cells from pubic and axillary hair follicles; previous studies have shown that beard cells take up and metabolize testosterone, retaining and secreting 5 alpha-dihydrotestosterone. After 24 h preincubation in serum-free Eagle's medium 199, 100-mm dishes of confluent cells were incubated for 2 h with 5 nM [1,2,6,7-3H]testosterone. Media were collected and the cells washed with phosphate-buffered saline and extracted with chloroform: methanol (2:1). After the addition of unlabeled and 14C-labeled marker steroids, the extracts were analyzed by a two-step thin-layer chromatography system; steroid identity was confirmed by recrystallization to a constant 3H/14C ratio. Beard and pubic dermal papilla cells were also incubated for 24 h, and the medium was analyzed at various times. The results from pubic and axillary primary cell lines were similar. In both cells and media the major steroid identified was testosterone, but significant amounts of androstenedione were present, indicating 17 beta-hydroxysteroid dehydrogenase activity; androstenedione was also identified within the cells, but a small amount of 5 alpha-dihydrotestosterone was only identified in one pubic cell line. Beard dermal papilla cells secreted large amounts of 5 alpha-dihydrotestosterone into the medium over 24 h in contrast to pubic cells, which produced only very small amounts. The pubic and axillary cell results contrasts with the observations of pronounced 5 alpha-dihydrotestosterone in beard cells and
Veiga-Lopez, Almudena; Astapova, Olga I.; Aizenberg, Esther F.; Lee, James S.; Padmanabhan, Vasantha
2009-01-01
Prenatal testosterone excess leads to neuroendocrine and periovulatory disruptions in the offspring culminating in progressive loss of cyclicity. It is unknown whether the mediary of these disruptions is androgen or estrogen, because testosterone can be aromatized to estrogen. Taking a reproductive life span approach of studying control, prenatal testosterone, and dihydrotestosterone-treated offspring, this study tested the hypothesis that disruptions in estradiol-negative but not -positive feedback effects are programmed by androgenic actions of testosterone and that these disruptions in turn will have an impact on the periovulatory hormonal dynamics. The approach was to test estradiol-negative and -positive feedback responses of all three groups of ovary-intact females during prepubertal age and then compare the periovulatory dynamics of luteinizing hormone, follicle-stimulating hormone, estradiol, and progesterone during the first breeding season. The findings show that estradiol-negative but not estradiol-positive feedback disruptions in prenatal testosterone-treated females are programmed by androgenic actions of prenatal testosterone excess and that follicular phase estradiol and gonadotropins surge disruptions during reproductive life are consistent with estrogenic programming. Additional studies carried out testing estradiol-positive feedback response over time found progressive deterioration of estradiol-positive feedback in prenatal testosterone-treated sheep until the time of puberty. Together, these findings provide insight into the mechanisms by which prenatal testosterone disrupts the reproductive axis. The findings may be of translational relevance since daughters of mothers with hyperandrogenism are at risk of increased exposure to androgens. PMID:19122183
Veeramani, S; Yuan, T-C; Lin, F-F; Lin, M-F
2009-01-01
p66Shc is shown to negatively regulate the life span in mice through reactive oxygen species (ROS) production. Recent reports, however, revealed that p66Shc protein level is significantly elevated in several human cancer tissues and growth-stimulated carcinoma cells, suggesting a mitogenic and carcinogenic role for p66Shc. In this communication, we demonstrate for the first time that p66Shc mediates androgenic growth signals in androgen-sensitive human prostate cancer cells through mitochondrial ROS production. Growth stimulation of prostate cancer cells with 5α-dihydrotestosterone (DHT) is accompanied by increased p66Shc level and ROS production, which is abolished by antioxidant treatments. However, antioxidant treatments do not affect the transcriptional activity of androgen receptor (AR) as observed by its inability to block DHT-induced prostate-specific antigen expression, an AR-dependent correlate of prostate cancer progression. Elevated expression of p66Shc by cDNA transfection increases the basal cell proliferation and, thus, reduces additional DHT-induced cell proliferation. Furthermore, DHT increases the translocation of p66Shc into mitochondria and its interaction with cytochrome c. Conversely, both redox-negative p66Shc mutant (W134F), which is deficient in cytochrome c interaction, and p66Shc small interfering RNA decrease DHT-induced cell proliferation. These results collectively reveal a novel role for p66Shc–ROS pathway in androgen-induced prostate cancer cell proliferation and, thus, may play a role in early prostate carcinogenesis. PMID:18504439
Hsu, Cheng-Lung; Liu, Jai-Shin; Wu, Po-Long; Guan, Hong-Hsiang; Chen, Yuh-Ling; Lin, An-Chi; Ting, Huei-Ju; Pang, See-Tong; Yeh, Shauh-Der; Ma, Wen-Lung; Chen, Chung-Jung; Wu, Wen-Guey; Chang, Chawnshang
2014-12-01
Treatment with individual anti-androgens is associated with the development of hot-spot mutations in the androgen receptor (AR). Here, we found that anti-androgens-mt-ARs have similar binary structure to the 5α-dihydrotestosterone-wt-AR. Phage display revealed that these ARs bound to similar peptides, including BUD31, containing an Fxx(F/H/L/W/Y)Y motif cluster with Tyr in the +5 position. Structural analyses of the AR-LBD-BUD31 complex revealed formation of an extra hydrogen bond between the Tyr+5 residue of the peptide and the AR. Functional studies showed that BUD31-related peptides suppressed AR transactivation, interrupted AR N-C interaction, and suppressed AR-mediated cell growth. Combination of peptide screening and X-ray structure analysis may serve as a new strategy for developing anti-ARs that simultaneously suppress both wt and mutated AR function. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.
Higuchi, Robert I; Arienti, Kristen L; López, Francisco J; Mani, Neelakhanda S; Mais, Dale E; Caferro, Thomas R; Long, Yun Oliver; Jones, Todd K; Edwards, James P; Zhi, Lin; Schrader, William T; Negro-Vilar, Andrés; Marschke, Keith B
2007-05-17
Recent interest in orally available androgens has fueled the search for new androgens for use in hormone replacement therapy and as anabolic agents. In pursuit of this, we have discovered a series of novel androgen receptor modulators derived from 7H-[1,4]oxazino[3,2-g]quinolin-7-ones. These compounds were synthesized and evaluated in competitive binding assays and an androgen receptor transcriptional activation assay. A number of compounds from the series demonstrated single-digit nanomolar agonist activity in vitro. In addition, lead compound (R)-16e was orally active in established rodent models that measure androgenic and anabolic properties of these agents. In this assay, (R)-16e demonstrated full efficacy in muscle and only partially stimulated the prostate at 100 mg/kg. These data suggest that these compounds may be utilized as selective androgen receptor modulators or SARMs. This series represents a novel class of compounds for use in androgen replacement therapy.
Modulation of AKR1C2 by curcumin decreases testosterone production in prostate cancer.
Ide, Hisamitsu; Lu, Yan; Noguchi, Takahiro; Muto, Satoru; Okada, Hiroshi; Kawato, Suguru; Horie, Shigeo
2018-04-01
Intratumoral androgen biosynthesis has been recognized as an essential factor of castration-resistant prostate cancer. The present study investigated the effects of curcumin on the inhibition of intracrine androgen synthesis in prostate cancer. Human prostate cancer cell lines, LNCaP and 22Rv1 cells were incubated with or without curcumin after which cell proliferation was measured at 0, 24, 48 and 72 hours, respectively. Prostate tissues from the transgenic adenocarcinoma of the mouse prostate (TRAMP) model were obtained after 1-month oral administration of 200 mg/kg/d curcumin. Testosterone and dihydrotestosterone concentrations in LNCaP prostate cancer cells were determined through LC-MS/MS assay. Curcumin inhibited cell proliferation and induced apoptosis of prostate cancer cells in a dose-dependent manner. Curcumin decreased the expression of steroidogenic acute regulatory proteins, CYP11A1 and HSD3B2 in prostate cancer cell lines, supporting the decrease of testosterone production. After 1-month oral administration of curcumin, Aldo-Keto reductase 1C2 (AKR1C2) expression was elevated. Simultaneously, decreased testosterone levels in the prostate tissues were observed in the TRAMP mice. Meanwhile, curcumin treatments considerably increased the expression of AKR1C2 in prostate cancer cell lines, supporting the decrease of dihydrotestosterone. Taken together, these results suggest that curcumin's natural bioactive compounds could have potent anticancer properties due to suppression of androgen production, and this could have therapeutic effects on prostate cancer. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.
García-Becerra, Rocío; Ordaz-Rosado, David; Noé, Gabriela; Chávez, Bertha; Cooney, Austin J; Larrea, Fernando
2012-02-01
7α-methyl-19-nortestosterone (MENT) is an androgen with potent gonadotropin inhibitory activity and prostate-sparing effects. These attributes give MENT advantages over testosterone as a male contraceptive, but, as in the case of testosterone, a partial dose-dependent suppression of spermatogenesis has been observed. Combination of testosterone or MENT with synthetic progestins improves the rate of azoospermia; however, it is unknown whether these combinations affect hormone androgenicity or exert synergistic effects via progestational or androgenic interaction. Herein, using transactivation assays, we examined the ability of MENT alone or combined with several 19-nor-derived synthetic progestins to activate androgen receptor (AR)-dependent gene transcription. In addition, the capability of 7α-methyl-estradiol (7α-methyl-E(2)), an aromatized metabolite of MENT, to transactivate gene transcription via estrogen receptor α (ERα; ESR1) or ERβ (ESR2) was also investigated. As expected, MENT induced gene transactivation through either the progesterone receptor (PGR) or the AR. MENT was as efficient as progesterone in activating PGR-mediated reporter gene expression, but it was ten times more potent than testosterone and dihydrotestoterone in activating of AR-driven gene expression. The addition of increasing concentrations of other 19-nortestosterone derivatives (norethisterone or levonorgestrel) did not affect, in a significant manner, the ability of MENT to activate AR-dependent reporter gene transcription. The same results were obtained with different cell lines. 7α-Methyl-E(2) resulted in potent estrogen activity via both ER subtypes with efficiency similar to natural E(2). These results suggest that the addition of 19-nortestosterone-derived progestins, as a hormonal adjuvant in male fertility strategies for effective spermatogenic suppression, does not display any detrimental effect that would interfere with MENT androgenic transcriptional activity.
Signorelli, S S; Barresi, V; Musso, N; Anzaldi, M; Croce, E; Fiore, V; Condorelli, D F
2008-12-01
Although animal studies support the hypothesis that androgenic biological actions may affect experimental atherosclerosis progression, evidence for a relationship between androgen effects and peripheral arterial disease (PAD), a common clinical form of atherosclerosis, is weak or contradictory. Testosterone, the main androgen hormone, is converted in a 5alpha-reduced form by enzymatic activities in the target cells and some specific actions are mediated by such metabolites. Steroid 5-alpha reductase isoenzymes (SRD5A1 and SRD5A2) catalyze the conversion to the bioactive potent androgen dihydrotestosterone and other reduced metabolites and represent relevant regulators of local hormonal actions. In the present study we tested for the association of selected single nucleotide polymorphisms (SNP) of SRD5A1 and SRD5A2 with symptomatic PAD patients. Two different SNP in the SRD5A1 were significantly associated which the PAD phenotype (p<0.03, odds ratio 1.73), while no association was found between PAD phenotypes and SRD5A2. Since the examined SRDA1 gene variant was previously associated with a low enzymatic activity, we suggest that a decreased local enzymatic conversion of testosterone may contribute to PAD genetic susceptibility.
Tepavčević, S; Milutinović, D V; Macut, D; Stanišić, J; Nikolić, M; Božić-Antić, I; Rodaljević, S; Bjekić-Macut, J; Matić, G; Korićanac, G
2015-05-01
Nitric oxide synthases (NOSs) and Na(+)/K(+)-ATPase are enzymes essential for regular functioning of the heart. Since both enzymes are under insulin and androgen regulation and since insulin action and androgen level were disturbed in polycystic ovary syndrome (PCOS), we hypothesized that cardiac nitric oxide (NO) production and sodium/potassium transport would be deteriorated in PCOS. To test our hypothesis we introduced animal model of PCOS based on dihydrotestosterone (DHT) treatment of female Wistar rats and analyzed protein expression, phosphorylation or subcellular localization of endothelial NOS (eNOS), inducible NOS (iNOS) and alpha subunits of Na(+)/K(+)-ATPase in the heart. Obtained results indicate that DHT treatment significantly decreased cardiac eNOS protein level and activating phosphorylation at serine 1,177, while inhibitory phosphorylation at threonine 495 was increased. In contrast to expression of eNOS, iNOS protein level in the heart of DHT-treated rats was significantly elevated. Furthermore, cardiac protein level of alpha 1 subunit of the ATPase, as well as its plasma membrane content, were decreased in rats with PCOS. In line with this, alpha 2 subunit protein level in fraction of plasma membranes was also significantly below control level. In conclusion, DHT treatment impaired effectiveness of NOSs and Na(+)/K(+)-ATPase in the female rat heart. Regarding the importance of NO production and sodium/potassium transport in the cardiac contraction and blood flow regulation, it implicates strong consequences of PCOS for heart functioning. © Georg Thieme Verlag KG Stuttgart · New York.
Bohl, Casey E; Wu, Zengru; Chen, Jiyun; Mohler, Michael L; Yang, Jun; Hwang, Dong Jin; Mustafa, Suni; Miller, Duane D; Bell, Charles E; Dalton, James T
2008-10-15
Selective androgen receptor modulators (SARMs) are essentially prostate sparing androgens, which provide therapeutic potential in osteoporosis, male hormone replacement, and muscle wasting. Herein we report crystal structures of the androgen receptor (AR) ligand-binding domain (LBD) complexed to a series of potent synthetic nonsteroidal SARMs with a substituted pendant arene referred to as the B-ring. We found that hydrophilic B-ring para-substituted analogs exhibit an additional region of hydrogen bonding not seen with steroidal compounds and that multiple halogen substitutions affect the B-ring conformation and aromatic interactions with Trp741. This information elucidates interactions important for high AR binding affinity and provides new insight for structure-based drug design.
Liu, Teresa T.; Grubisha, Melanie J.; Frahm, Krystle A.; Wendell, Stacy G.; Liu, Jiayan; Ricke, William A.; Auchus, Richard J.; DeFranco, Donald B.
2016-01-01
Current pharmacotherapies for symptomatic benign prostatic hyperplasia (BPH), an androgen receptor-driven, inflammatory disorder affecting elderly men, include 5α-reductase (5AR) inhibitors (i.e. dutasteride and finasteride) to block the conversion of testosterone to the more potent androgen receptor ligand dihydrotestosterone. Because dihydrotestosterone is the precursor for estrogen receptor β (ERβ) ligands, 5AR inhibitors could potentially limit ERβ activation, which maintains prostate tissue homeostasis. We have uncovered signaling pathways in BPH-derived prostate epithelial cells (BPH-1) that are impacted by 5AR inhibition. The induction of apoptosis and repression of the cell adhesion protein E-cadherin by the 5AR inhibitor dutasteride requires both ERβ and TGFβ. Dutasteride also induces cyclooxygenase type 2 (COX-2), which functions in a negative feedback loop in TGFβ and ERβ signaling pathways as evidenced by the potentiation of apoptosis induced by dutasteride or finasteride upon pharmacological inhibition or shRNA-mediated ablation of COX-2. Concurrently, COX-2 positively impacts ERβ action through its effect on the expression of a number of steroidogenic enzymes in the ERβ ligand metabolic pathway. Therefore, effective combination pharmacotherapies, which have included non-steroidal anti-inflammatory drugs, must take into account biochemical pathways affected by 5AR inhibition and opposing effects of COX-2 on the tissue-protective action of ERβ. PMID:27226548
Hagger, C; Bachevalier, J
1991-10-25
The ability to perform on a concurrent visual discrimination task with 24-h intertrial intervals (24-h ITI task) develops a few weeks earlier in female than in male infant monkeys. To test whether this sex difference was related to the presence of perinatal androgens, plasma testosterone levels were reduced in male infant monkeys by neonatal orchiectomy and increased in neonatally ovariectomized female infant monkeys by treatment with either testosterone propionate (TP) or its reduced metabolite, dihydrotestosterone (DHT). At 3 months of age, the animals were tested on the 24-h ITI task and their performance compared with that of age-matched intact male and female monkeys. Orchiectomy which was followed by a slight but visible atrophy of the external genitalia, hastened performance of male infant monkeys to the level of intact infant females. Conversely, androgenization of ovariectomized female infant monkeys given DHT, which had only a slight virilizing effect on the external genitalia, showed the learning of these female infants to the rate of intact male infant monkeys. Curiously, although TP treatment in ovariectomized female infant monkeys was more effective than DHT in virilizing the external genitalia, it failed to slow the rate of learning. This dissociation between the effects of TP and DHT on external genital organs and learning abilities is discussed in terms of possible differences in dose-dependent, time-dependent, and receptor-binding mechanisms of the two androgens. The present study provides further evidence that early androgen secretions affect the organization not only of brain structures related to primary sexual characteristics but also of those related to learning abilities.
AN ENVIRONMENTAL ANTIANDROGEN, VINCLOZOLIN, ALTERS THE ORGANIZATION OF PLAY BEHAVIOR
ABSTRACT
During mammalian sexual differentiation, the androgens, testosterone and dihydrotestosterone are critical for the organization of the male phenotype. In rats, play behavior is sexually dimorphic. Administration of exogenous androgens during the perinatal period r...
EFFECTS OF ENVIRONMENTAL ANTIANDROGENS ON REPRODUCTIVE DEVELOPMENT IN EXPERIMENTAL ANIMALS
In mammals, the androgens testosterone (T) and dihydrotestosterone (DHT) are critical for normal male reproductive development and function. In humans, drugs that act as androgen receptor (AR) agonists and antagonists or inhibit fetal steroidogenesis can cause pseudohermaphrodi...
EFFECTS OF ENVIRONMENTAL ANTIANDROGENS IN EXPERIMENTAL ANIMALS
In mammals, the androgens testosterone (T) and dihydrotestosterone (DHT) are critical for normal male reproductive development and function. In humans, drugs that act as androgen receptor (AR) agonists and antagonists or inhibit fetal steroidogenesis can cause pseudohermaphrodi...
Abstract:
During mammalian sexual differentiation, androgens, and specifically, testosterone and dihydrotestosterone, are critical for the organization of the male phenotype. In rats, social play behavior is organized by androgens during the neonatal period. Males play more ...
Ambrosio, Javier R.; Valverde-Islas, Laura; Nava-Castro, Karen E.; Palacios- Arreola, M. Isabel; Ostoa-Saloma, Pedro; Reynoso-Ducoing, Olivia; Escobedo, Galileo; Ruíz-Rosado, Azucena; Dominguez-Ramírez, Lenin; Morales-Montor, Jorge
2015-01-01
The effects of testosterone (T4) and dihydrotestosterone (DHT) on the survival of the helminth cestode parasite Taenia crassiceps, as well as their effects on actin, tubulin and myosin expression and their assembly into the excretory system of flame cells are described in this paper. In vitro evaluations on parasite viability, flow cytometry, confocal microscopy, video-microscopy of live flame cells, and docking experiments of androgens interacting with actin, tubulin, and myosin were conducted. Our results show that T4 and DHT reduce T. crassiceps viability in a dose- and time-dependent fashion, reaching 90% of mortality at the highest dose used (40 ng/ml) and time exposed (10 days) in culture. Androgen treatment does not induce differences in the specific expression pattern of actin, tubulin, and myosin isoforms as compared with control parasites. Confocal microscopy demonstrated a strong disruption of the parasite tegument, with reduced assembly, shape, and motion of flame cells. Docking experiments show that androgens are capable of affecting parasite survival and flame cell morphology by directly interacting with actin, tubulin and myosin without altering their protein expression pattern. We show that both T4 and DHT are able to bind actin, tubulin, and myosin affecting their assembly and causing parasite intoxication due to impairment of flame cell function. Live flame cell video microscopy showing a reduced motion as well changes in the shape of flame cells are also shown. In summary, T4 and DHT directly act on T. crassiceps cysticerci through altering parasite survival as well as the assembly and function of flame cells. PMID:26076446
Li, Xin; Pishdari, Bano; Cui, Peng; Hu, Min; Yang, Hong-Ping; Guo, Yan-Rong; Jiang, Hong-Yuan; Feng, Yi; Billig, Håkan; Shao, Ruijin
2015-01-01
The failure of reproductive success in polycystic ovary syndrome (PCOS) patients could be in part due to endometrial dysfunction. However, no studies have investigated any causality between androgen, androgen receptor (AR) expression, and adenosine monophosphate activated protein kinase (AMPK) activation in the endometrium under physiological and pathological conditions. In the present study, we show that 1) endometrial AR expression levels fluctuate in non-PCOS and PCOS patients during the menstrual cycle; 2) the menstrual phase-dependent alteration of p-AMPKα expression occurs in non-PCOS patients but not in PCOS patients; 3) AR expression is higher in PCOS patients than non-PCOS patients during hyperplasia while AMPKα activation (indicated by the ratio of p-AMPKα to AMPKα); and 4) co-localization of AR and Ki-67 in epithelial cell nuclei is observed in endometrial hyperplasia. Importantly, using in vitro human tissue culture and an in vivo 5α-dihydrotestosterone-treated rat model, we show that the action of androgen on AMPKα activation is likely mediated through nuclear AR, especially in epithelial cells. Collectively, we present evidence that AR expression and AMPKα activation depend on menstrual cycle phase and the presence of PCOS, and the data suggest that AR-mediated regulation of AMPKα activation might play a role in the development of endometrial hyperplasia. PMID:26681917
De Mol, Eva; Fenwick, R. Bryn; Phang, Christopher T. W.; Buzón, Victor; Szulc, Elzbieta; de la Fuente, Alex; Escobedo, Albert; García, Jesús; Bertoncini, Carlos W.; Estébanez-Perpiñá, Eva; McEwan, Iain J.; Riera, Antoni; Salvatella, Xavier
2016-01-01
Castration-resistant prostate cancer is the lethal condition suffered by prostate cancer patients that become refractory to androgen deprivation therapy. EPI-001 is a recently identified compound active against this condition that modulates the activity of the androgen receptor, a nuclear receptor that is essential for disease progression. The mechanism by which this compound exerts its inhibitory activity is however not yet fully understood. Here we show, by using high resolution solution nuclear magnetic resonance spectroscopy, that EPI-001 selectively interacts with a partially folded region of the transactivation domain of the androgen receptor, known as transactivation unit 5, that is key for the ability of prostate cells to proliferate in the absence of androgens, a distinctive feature of castration-resistant prostate cancer. Our results can contribute to the development of more potent and less toxic novel androgen receptor antagonists for treating this disease. PMID:27356095
Narayanan, Ramesh; Ahn, Sunjoo; Cheney, Misty D; Yepuru, Muralimohan; Miller, Duane D; Steiner, Mitchell S; Dalton, James T
2014-01-01
The androgen receptor (AR) is the most highly expressed steroid receptor in breast cancer with 75-95% of estrogen receptor (ER)-positive and 40-70% of ER-negative breast cancers expressing AR. Though historically breast cancers were treated with steroidal androgens, their use fell from favor because of their virilizing side effects and the emergence of tamoxifen. Nonsteroidal, tissue selective androgen receptor modulators (SARMs) may provide a novel targeted approach to exploit the therapeutic benefits of androgen therapy in breast cancer. Since MDA-MB-453 triple-negative breast cancer cells express mutated AR, PTEN, and p53, MDA-MB-231 triple-negative breast cancer cells stably expressing wildtype AR (MDA-MB-231-AR) were used to evaluate the in vitro and in vivo anti-proliferative effects of SARMs. Microarray analysis and epithelial:mesenchymal stem cell (MSC) co-culture signaling studies were performed to understand the mechanisms of action. Dihydrotestosterone and SARMs, but not bicalutamide, inhibited the proliferation of MDA-MB-231-AR. The SARMs reduced the MDA-MB-231-AR tumor growth and tumor weight by greater than 90%, compared to vehicle-treated tumors. SARM treatment inhibited the intratumoral expression of genes and pathways that promote breast cancer development through its actions on the AR. SARM treatment also inhibited the metastasis-promoting paracrine factors, IL6 and MMP13, and subsequent migration and invasion of epithelial:MSC co-cultures. 1. AR stimulation inhibits paracrine factors that are important for MSC interactions and breast cancer invasion and metastasis. 2. SARMs may provide promise as novel targeted therapies to treat AR-positive triple-negative breast cancer.
Narayanan, Ramesh; Ahn, Sunjoo; Cheney, Misty D.; Yepuru, Muralimohan; Miller, Duane D.; Steiner, Mitchell S.; Dalton, James T.
2014-01-01
Abstract Introduction The androgen receptor (AR) is the most highly expressed steroid receptor in breast cancer with 75–95% of estrogen receptor (ER)-positive and 40–70% of ER-negative breast cancers expressing AR. Though historically breast cancers were treated with steroidal androgens, their use fell from favor because of their virilizing side effects and the emergence of tamoxifen. Nonsteroidal, tissue selective androgen receptor modulators (SARMs) may provide a novel targeted approach to exploit the therapeutic benefits of androgen therapy in breast cancer. Materials and Methods Since MDA-MB-453 triple-negative breast cancer cells express mutated AR, PTEN, and p53, MDA-MB-231 triple-negative breast cancer cells stably expressing wildtype AR (MDA-MB-231-AR) were used to evaluate the in vitro and in vivo anti-proliferative effects of SARMs. Microarray analysis and epithelial:mesenchymal stem cell (MSC) co-culture signaling studies were performed to understand the mechanisms of action. Results Dihydrotestosterone and SARMs, but not bicalutamide, inhibited the proliferation of MDA-MB-231-AR. The SARMs reduced the MDA-MB-231-AR tumor growth and tumor weight by greater than 90%, compared to vehicle-treated tumors. SARM treatment inhibited the intratumoral expression of genes and pathways that promote breast cancer development through its actions on the AR. SARM treatment also inhibited the metastasis-promoting paracrine factors, IL6 and MMP13, and subsequent migration and invasion of epithelial:MSC co-cultures. Conclusion 1. AR stimulation inhibits paracrine factors that are important for MSC interactions and breast cancer invasion and metastasis. 2. SARMs may provide promise as novel targeted therapies to treat AR-positive triple-negative breast cancer. PMID:25072326
Androgen effects on skeletal muscle: implications for the development and management of frailty
O’Connell, Matthew DL; Wu, Frederick CW
2014-01-01
Androgens have potent anabolic effects on skeletal muscle and decline with age in parallel to losses in muscle mass and strength. This loss of muscle mass and function, known as sarcopenia, is the central event in development of frailty, the vulnerable health status that presages adverse outcomes and rapid functional decline in older adults. The potential role of falling androgen levels in the development of frailty and their utility as function promoting therapies in older men has therefore attracted considerable attention. This review summarizes current concepts and definitions in muscle ageing, sarcopenia and frailty, and evaluates recent developments in the study of androgens and frailty. Current evidence from observational and interventional studies strongly supports an effect of androgens on muscle mass in ageing men, but effects on muscle strength and particularly physical function have been less clear. Androgen treatment has been generally well–tolerated in studies of older men, but concerns remain over higher dose treatments and use in populations with high cardiovascular risk. The first trials of selective androgen receptor modulators (SARMs) suggest similar effects on muscle mass and function to traditional androgen therapies in older adults. Important future directions include the use of these agents in combination with exercise training to promote functional ability across different populations of older adults, as well as more focus on the relationships between concurrent changes in hormone levels, body composition and physical function in observational studies. PMID:24457838
Koh, Yi T.; Gray, Andrew; Higgins, Sean A.; Hubby, Bolyn; Kast, W. Martin
2009-01-01
Background Androgen ablation (AA) causes apoptosis of normal and neoplastic prostate cells. It is a standard treatment for advanced prostate cancer. Androgen ablation-mediated immunological effects include bone marrow hyperplasia, thymic regeneration, T and B cell lymphopoeisis and restoration of age-related peripheral T cell dysfunction. Androgens also regulate the transcription of several cytokines. Dendritic cells (DC) are the most potent antigen presenting cells that can activate antigen-specific naïve T cells. Despite myriad clinical trials involving DC-based prostate cancer immunotherapies, the effects of AA on DC function remain largely uncharacterized. Therefore, we investigated the effects of AA on DC and whether it could improve the efficacy of prostate cancer immunotherapy. Methods Cytokine expression changes due to AA were quantified by multiplex ELISA. Flow cytometry was used to assess AA-mediated effects on DC maturation and expression of costimulatory markers. Mixed leukocyte reactions and cell-mediated lysis assays elucidated the role of androgens in DC function. The effect of AA on the efficacy of vaccination against a prostate tumor-associated antigen was tested using Elispot assays. Results Androgen ablation increased dendritic cell maturation and costimulatory marker expression, but had no effect on DC costimulatory function. However, DC isolated from castrated mice increased the expression of key cytokines by antigen-experienced T cells while decreasing their expression in naïve cells. Finally, androgen ablation improved immune responses to vaccination only when applied after immunization. Conclusion Androgen ablation causes differential effects of DC on primary and secondary T cell responses, thus augmenting vaccine immunogenicity only when applied after immunization. PMID:19143030
Aiken, W D
2011-12-01
It is hypothesised that seemingly disparate and unrelated phenomena clustering in persons of African descent living in the Americas such as outstanding sprinting ability and high prostate cancer incidence and mortality are in fact related and emerge from enhanced testosterone responsiveness in descendants of African slaves surviving the transatlantic trade in Africans. It is postulated that the ability to have survived the middle passage was positively correlated with greater responsiveness of the androgen receptor to its primary ligands dihydrotestosterone and testosterone, and that slaves possessing more responsive androgen receptors experienced a survival advantage engendered by the enhanced anabolic effects which accrued such as increased red cell mass and therefore greater oxygen carrying capacity and tissue oxygen delivery enabling these slaves to tolerate stifling conditions in the hull of the slave ship, increased lean muscle mass and therefore greater surface area to volume ratio resulting in easier ability to dissipate heat and remain cool, and increased skin thickness and sebum production resisting the macerating effect of lying in admixed bodily fluids below deck. These androgen effects as well as others would have produced a survival advantage under the severe selection pressure created by the inhumane and physiologically challenging circumstances under which the slaves were transported from the interior of the African continent and West Africa to the 'New World'. This would result in a population shift favouring increased androgen receptor responsiveness in descendants of African slaves populating the Americas and a corresponding geographic and racial distribution of androgen related phenomena such as sprinting prowess and prostate cancer. African-Americans having the highest prostate cancer incidence rate and the Caribbean having the highest prostate cancer mortality rates in the world are consistent with this hypothesis as is the observation that
Chhipa, Rishi Raj; Halim, Danny; Cheng, Jinrong; Zhang, Huan Yi; Mohler, James L.; Ip, Clement; Wu, Yue
2014-01-01
BACKGROUND Finasteride and dutasteride were developed originally as 5α-reductase inhibitors to block the conversion of testosterone to dihydrotestosterone (DHT). These drugs may possess off-target effects on the androgen receptor (AR) due to their structural similarity to DHT. METHODS A total of 4 human prostate cancer cell models were examined: LNCaP (T877A mutant AR), 22Rv1 (H874Y mutant AR), LAPC4 (wild type AR) and VCaP (wild type AR). Cells were cultured in 10% charcoal-stripped fetal bovine serum, either with or without DHT added to the medium. AR activity was evaluated using the ARE-luciferase assay or the expression of AR regulated genes. RESULTS Dutasteride was more potent than finasteride in interfering with DHT-stimulated AR signaling. Disruption of AR function was accompanied by decreased cell growth. Cells that rely on DHT for protection against death were particularly vulnerable to dutasteride. Different prostate cancer cell models exhibited different sensitivities to dutasteride and finasteride. LNCaP was most sensitive, LAPC4 and VCaP were intermediate, while 22Rv1 was least sensitive. Regardless of the AR genotype, if AR was transfected into drug-sensitive cells, AR was inhibited by drug treatment; and if AR was transfected into drug-resistant cells, AR was not inhibited. CONCLUSIONS The direct inhibitory effect of dutasteride or finasteride on AR signaling is cell line specific. Mutations in the ligand binding domain of AR do not appear to play a significant role in influencing the AR antagonistic effect of these drugs. Subcellular constituent is an important factor in determining the drug effect on AR function. PMID:23813737
Androgen Receptor-Mediated Growth Suppression of HPr-1AR and PC3-Lenti-AR Prostate Epithelial Cells
Bolton, Eric C.
2015-01-01
The androgen receptor (AR) mediates the developmental, physiologic, and pathologic effects of androgens including 5α-dihydrotestosterone (DHT). However, the mechanisms whereby AR regulates growth suppression and differentiation of luminal epithelial cells in the prostate gland and proliferation of malignant versions of these cells are not well understood, though they are central to prostate development, homeostasis, and neoplasia. Here, we identify androgen-responsive genes that restrain cell cycle progression and proliferation of human prostate epithelial cell lines (HPr-1AR and PC3-Lenti-AR), and we investigate the mechanisms through which AR regulates their expression. DHT inhibited proliferation of HPr-1AR and PC3-Lenti-AR, and cell cycle analysis revealed a prolonged G1 interval. In the cell cycle, the G1/S-phase transition is initiated by the activity of cyclin D and cyclin-dependent kinase (CDK) complexes, which relieve growth suppression. In HPr-1AR, cyclin D1/2 and CDK4/6 mRNAs were androgen-repressed, whereas CDK inhibitor, CDKN1A, mRNA was androgen-induced. The regulation of these transcripts was AR-dependent, and involved multiple mechanisms. Similar AR-mediated down-regulation of CDK4/6 mRNAs and up-regulation of CDKN1A mRNA occurred in PC3-Lenti-AR. Further, CDK4/6 overexpression suppressed DHT-inhibited cell cycle progression and proliferation of HPr-1AR and PC3-Lenti-AR, whereas CDKN1A overexpression induced cell cycle arrest. We therefore propose that AR-mediated growth suppression of HPr-1AR involves cyclin D1 mRNA decay, transcriptional repression of cyclin D2 and CDK4/6, and transcriptional activation of CDKN1A, which serve to decrease CDK4/6 activity. AR-mediated inhibition of PC3-Lenti-AR proliferation occurs through a similar mechanism, albeit without down-regulation of cyclin D. Our findings provide insight into AR-mediated regulation of prostate epithelial cell proliferation. PMID:26372468
Androgen-responsive gene database: integrated knowledge on androgen-responsive genes.
Jiang, Mei; Ma, Yunsheng; Chen, Congcong; Fu, Xuping; Yang, Shu; Li, Xia; Yu, Guohua; Mao, Yumin; Xie, Yi; Li, Yao
2009-11-01
Androgen signaling plays an important role in many biological processes. Androgen Responsive Gene Database (ARGDB) is devoted to providing integrated knowledge on androgen-controlled genes. Gene records were collected on the basis of PubMed literature collections. More than 6000 abstracts and 950 original publications were manually screened, leading to 1785 human genes, 993 mouse genes, and 583 rat genes finally included in the database. All the collected genes were experimentally proved to be regulated by androgen at the expression level or to contain androgen-responsive regions. For each gene important details of the androgen regulation experiments were collected from references, such as expression change, androgen-responsive sequence, response time, tissue/cell type, experimental method, ligand identity, and androgen amount, which will facilitate further evaluation by researchers. Furthermore, the database was integrated with multiple annotation resources, including National Center for Biotechnology Information, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes pathway, to reveal the biological characteristics and significance of androgen-regulated genes. The ARGDB web site is mainly composed of the Browse, Search, Element Scan, and Submission modules. It is user friendly and freely accessible at http://argdb.fudan.edu.cn. Preliminary analysis of the collected data was performed. Many disease pathways, such as prostate carcinogenesis, were found to be enriched in androgen-regulated genes. The discovered androgen-response motifs were similar to those in previous reports. The analysis results are displayed in the web site. In conclusion, ARGDB provides a unified gateway to storage, retrieval, and update of information on androgen-regulated genes.
Oriental herbs as a source of novel anti-androgen and prostate cancer chemopreventive agents.
Lu, Junxuan; Kim, Sung-Hoon; Jiang, Cheng; Lee, HyoJeong; Guo, Junming
2007-09-01
Androgen and androgen receptor (AR) signaling are crucial for the genesis of prostate cancer (PCa), which can often develop into androgen-ligand-independent diseases that are lethal to the patients. Recent studies show that even these hormone-refractory PCa require ligand-independent AR signaling for survival. As current chemotherapy is largely ineffective for PCa and has serious toxic sideeffects, we have initiated a collaborative effort to identify and develop novel, safe and naturally occurring agents that target AR signaling from Oriental medicinal herbs for the chemoprevention and treatment of PCa. We highlight our discovery of decursin from an Oriental formula containing Korean Angelica gigas Nakai (Dang Gui) root as a novel anti-androgen/AR agent. We have identified the following mechanisms to account for the specific anti-AR actions: rapid block of AR nuclear translocation, inhibition of binding of 5alpha-dihydrotestesterone to AR and increased proteasomal degradation of AR protein. Furthermore, decursin lacks the agonist activity of the "pure" anti-androgen bicalutamide and is more potent than bicalutamide in inducing PCa apoptosis. Structure-activity analyses reveal a critical requirement of the side-chain on decursin or its structural isomer decursinol angelate for anti-AR, cell cycle arrest and proapoptotic activities. This work demonstrates the feasibility of using activity-guided fractionation in cell culture assays combined with mechanistic studies to identify novel anti-androgen/ AR agents from complex herbal mixtures.
Svensson, Johan; Fick, Jerker; Brandt, Ingvar; Brunström, Björn
2014-02-01
Synthetic steroid hormones from contraceptive pharmaceuticals have become global aquatic contaminants. Progestins, the synthetic analogs to progesterone, are receiving increasing attention as contaminants and have been shown to impair reproduction in fish and amphibians at low ng L(-1) concentrations. Certain progestins, such as levonorgestrel have androgenic properties and seem to be several orders of magnitude more potent in terms of reproductive impairment in fish than non-androgenic progestins and progestagens. We recently reported that levonorgestrel has strong androgenic effects in female three-spined sticklebacks (Gasterosteus aculeatus), including induction of the normally male-specific glue protein spiggin and suppression of vitellogenesis. In light of this we investigated if exposure to levonorgestrel could disrupt the highly androgen-dependent seasonal reproductive cycle in male sticklebacks. Male sticklebacks that were in the final stage of a breeding period were exposed to various concentrations of levonorgestrel for six weeks in winter conditions in terms of light and temperature, after which reproductive status was evaluated from gross morphology, histology and key gene transcript levels. During the experimental period the controls had transitioned from full breeding condition into the non-breeding state, including regression of secondary sex characteristics, cessation of spiggin production in the kidney, and resumption of spermatogenesis in the testes. This is ascribed to the natural drop in plasma androgen levels after breeding. However, in the groups concurrently exposed to levonorgestrel, transition to the non-breeding condition was dose-dependently inhibited. Our results show that levonorgestrel can disrupt the seasonal breeding cycle in male sticklebacks. The fitness costs of such an effect could be detrimental to natural stickleback populations. Some effects occurred at a levonorgestrel concentration of 6.5 ng L(-1), well within the range of
In Vitro Androgen Bioassays as a Detection Method for Designer Androgens
Cooper, Elliot R.; McGrath, Kristine C. Y.; Heather, Alison K.
2013-01-01
Androgens are the class of sex steroids responsible for male sexual characteristics, including increased muscle mass and decreased fat mass. Illicit use of androgen doping can be an attractive option for those looking to enhance sporting performance and/or physical appearance. The use of in vitro bioassays to detect androgens, especially designer or proandrogens, is becoming increasingly important in combating androgen doping associated with nutritional supplements. The nutritional sports supplement market has grown rapidly throughout the past decade. Many of these supplements contain androgens, designer androgens or proandrogens. Many designer or proandrogens cannot be detected by the standard highly-sensitive screening methods such as gas chromatography-mass spectrometry because their chemical structure is unknown. However, in vitro androgen bioassays can detect designer and proandrogens as these assays are not reliant on knowing the chemical structure but instead are based on androgen receptor activation. For these reasons, it may be advantageous to use routine androgen bioassay screening of nutraceutical samples to help curb the increasing problem of androgen doping. PMID:23389345
Hata, Shuko; Ise, Kazue; Azmahani, Abdullah; Konosu-Fukaya, Sachiko; McNamara, Keely May; Fujishima, Fumiyoshi; Shimada, Keiji; Mitsuzuka, Koji; Arai, Yoichi; Sasano, Hironobu; Nakamura, Yasuhiro
2017-12-01
Bladder urothelial carcinoma is increasing in incidence with age and its prognosis could become worse when accompanied with metastasis. Effective treatment of these advanced patients is required and it becomes important to understand its underlying biology of this neoplasm, especially with regard to its biological pathways. A potential proposed pathway is androgen receptor (AR)-mediated intracellular signaling but the details have remained relatively unexplored. The expression of AR, 5α-reductase type1 (5αR1) and 5α-reductase type2 (5αR2) were examined in the bladder cancer cell line T24 and surgical pathology specimens. We also evaluated the status of androgen related cell proliferation and migration using the potent, non-aromatizable androgen agonist 5α-dihydrotestosterone (DHT). DHT treatment significantly increased AR mRNA expression level, but not those of 5αR1 and 5αR2 in T24 cells. DHT also suppressed cellular migration with weaker and opposite effects on cell proliferation. A significant inverse correlation was detected between pT stage and AR, 5αR1 and 5αR2 immunoreactivity. Inverse correlations detected between tumor grade and AR/androgen metabolizing enzyme also suggested that the loss of AR and androgen-producing enzymes could be associated with tumor progression. Effects of DHT on cells also suggest that androgens may regulate cellular behavior. Copyright © 2017 Elsevier Inc. All rights reserved.
Chisamore, Michael J; Gentile, Michael A; Dillon, Gregory Michael; Baran, Matthew; Gambone, Carlo; Riley, Sean; Schmidt, Azriel; Flores, Osvaldo; Wilkinson, Hilary; Alves, Stephen E
2016-10-01
which may provide potent anti-androgenic activity at the prostate yet protective activity on skeletal muscle and behavior in patients. Copyright © 2016 Elsevier Ltd. All rights reserved.
Limón-Morales, Ofelia; Soria-Fregozo, Cesar; Arteaga-Silva, Marcela; González, Marisela Hernández; Vázquez-Palacios, Gonzalo; Bonilla-Jaime, Herlinda
2014-11-01
Male sexual behavior (MSB) in rodents, in both its consummatory and motivational components, is regulated by hormones such as testosterone, 17β-estradiol and 5-α-dihydrotestosterone. In experiments, neonatal treatment with clomipramine (CMI; a serotonin reuptake inhibitor) reproduces some of the signs of depression in adult age, including reduced sexual behavior manifested in a lower percentage of subjects that mount, intromit and ejaculate, although their testosterone levels were not altered. However, the effect of this treatment on estrogen levels and the consequences of hormone substitution using 17β-estradiol and 5-α-dihydrotestosterone on the expression of male sexual behavior are still unknown. Therefore, the objective of the present study was to analyze the effect of neonatal treatment with CMI on plasma testosterone and 17β-estradiol levels, and the role of testosterone, 17β-estradiol and 5-α-dihydrotestosterone in altering the consummatory and motivational components of sexual behavior in male rats. To this end, it analyzed the copulatory parameters and sexual incentive motivation (SIM) of rats treated with CMI under two conditions: basal and post-hormone replacements. Neonatal treatment with CMI did not affect plasma testosterone or 17β-estradiol concentrations, but did decrease both the consummatory component and sexual motivation according to the results of the SIM test. These aspects were recovered after administering 17β-estradiol +5-α-dihydrotestosterone, but not testosterone. Copyright © 2014 Elsevier Inc. All rights reserved.
McMahon, Chris G; Shusterman, Neil; Cohen, Brian
2017-07-01
Implantation of testosterone doses of at least 150 to 450 mg (ie, two to six pellets) is common clinical practice despite a lack of prospective data. To evaluate pharmacokinetics, clinical efficacy, safety, and patient-reported outcomes in men with androgen deficiency who received implantation of testosterone pellets (900 mg) in an open-label study. Men with androgen deficiency (serum testosterone < 300 ng/dL [10.4 nmol/L]) were screened and received 12 testosterone pellets (900 mg). Serum hormone measurements (total and free testosterone, dihydrotestosterone, and estradiol) were obtained on days 1, 5, 8, 15, 29, 57, 85, and 113. All hormones were assayed using validated liquid chromatography and tandem mass spectrometry. Pharmacokinetics of selected hormones was determined. The patient-reported International Index of Erectile Function (IIEF), Center for Epidemiologic Studies Depression (CES-D), and Androgen Deficiency in the Aging Male (qADAM) questionnaires also were performed. Patients rated their satisfaction on a scale from 1 (very satisfied) to 5 (very dissatisfied). Adverse events were monitored throughout. Fifteen patients were included (mean age = 54.5 years, SD = 8.6 years). Mean baseline total testosterone concentration was 241.6 ng/dL (SD = 88.8 ng/dL; mean = 8.4 nmol/L, SD = 3.1 nmol/L). Mean testosterone serum concentrations fluctuated during the first 2 weeks (range = 300-1,000 ng/dL, 10.4-34.7 nmol/L) but remained higher than or equal to 300 ng/dL (10.4 nmol/L) through day 113. Concentrations of free testosterone, dihydrotestosterone, and estradiol mirrored that of total testosterone. Male functioning (IIEF score), depression (CES-D total score), and androgen-deficiency symptoms (qADAM total score) improved from baseline. Most patients were "very satisfied" (40.0%) or "quite satisfied" (26.7%) with treatment. Testosterone pellets were well tolerated. Pellet extrusion and polycythemia occurred in one patient each. Implantation of high doses
Shiota, Masaki; Fujimoto, Naohiro; Yokomizo, Akira; Takeuchi, Ario; Itsumi, Momoe; Inokuchi, Junichi; Tatsugami, Katsunori; Uchiumi, Takeshi; Naito, Seiji
2015-09-01
De novo androgen synthesis is thought to be involved in the progression to castration-resistant prostate cancer (CRPC) during androgen-deprivation therapy (ADT). During androgen synthesis, 5α-reductase encoded by SRD5A catalyses testosterone into more active dihydrotestosterone and may be involved in the progression to CRPC. Then, this study aimed to reveal the association between genetic variations in SRD5A and the prognosis in metastatic prostate cancer. We studied the polymorphisms rs518673 and rs166050 in SRD5A1, and rs12470143, rs523349, rs676033 and rs2208532 in SRD5A2 as well as the time to CRPC progression and overall survival in 104 patients with metastatic prostate cancer that had undergone primary ADT. The association between the polymorphisms and the progression to CRPC as well as overall survival was examined. Patients carrying the more active GG genotype in SRD5A2 rs523349 exhibited a higher risk of the progression (hazard ration [95% confidence interval], 1.93 [1.14-3.14], p=0.016) and death (hazard ration [95% confidence interval], 2.14 [1.16-3.76], p=0.016), compared with less active GC/CC genotypes in SRD5A2 rs523349. High 5α-reductase activity due to the polymorphism in SRD5A2 may contribute to resistance to ADT. Furthermore, SRD5A2 rs523349 polymorphism may be a promising biomarker for metastatic prostate cancer patients treated with primary ADT and a molecular target for advanced prostate cancer. Copyright © 2015 Elsevier Ltd. All rights reserved.
The antiandrogenic effect of finasteride against a mutant androgen receptor
Chhipa, Rishi Raj; Zhang, Haitao; Ip, Clement
2011-01-01
Finasteride is known to inhibit Type 2 5α-reductase and thus block the conversion of testosterone to dihydrotestosterone (DHT). The structural similarity of finasteride to DHT raises the possibility that finasteride may also interfere with the function of the androgen receptor (AR). Experiments were carried out to evaluate the antiandrogenic effect of finasteride in LNCaP, C4-2 and VCaP human prostate cancer cells. Finasteride decreased DHT binding to AR, and DHT-stimulated AR activity and cell growth in LNCaP and C4-2 cells, but not in VCaP cells. LNCaP and C4-2 (derived from castration-resistant LNCaP) cells express the T877A mutant AR, while VCaP cells express the wild-type AR. When PC-3 cells, which are AR-null, were transfected with either the wild-type or the T877A mutant AR, only the mutant AR-expressing cells were sensitive to finasteride inhibition of DHT binding. Peroxiredoxin-1 (Prx1) is a novel endogenous facilitator of AR binding to DHT. In Prx1-rich LNCaP cells, the combination of Prx1 knockdown and finasteride was found to produce a greater inhibitory effect on AR activity and cell growth than either treatment alone. The observation suggests that cells with a low expression of Prx1 are likely to be more responsive to the antiandrogenic effect of finasteride. Additional studies showed that the efficacy of finasteride was comparable to that of bicalutamide (a widely used non-steroidal antiandrogen). The implication of the above findings is discussed in the context of developing strategies to improve the outcome of androgen deprivation therapy. PMID:21386657
Biochemistry and physiology of anabolic androgenic steroids doping.
Lippi, G; Franchini, M; Banfi, G
2011-05-01
Anabolic Androgenic Steroids (AASs) are chemical and pharmacological derivatives of the male hormone testosterone which are widely used for increasing burst and sprinting activities in sports. Although AASs are thought to be transversal to the plurality of sports disciplines, they are principally misused by bodybuilders, weightlifters, shot, hammer, discus or javelin throwers, rugby and American football players as well as by swimmers and runners. AAS exert a kaleidoscope of effects on human biology, principally through the 5-α-reductase-mediated conversion into dihydrotestosterone, the aromatase-mediated conversion into female sex hormones, a competitive antagonism to the glucocorticoid receptors, the potential stimulation of erythropoietin secretion as well as psychoactive effects on the brain. The influence of AASs on physical performance is still undefined, since the large number of studies published so far have described discordant and often contradictory outcomes. Nevertheless, animal and human investigations support the hypothesis that the administration of AASs might increase lean body mass, muscle mass, and maximal voluntary strength especially in men, so that they would represent an appealing form of doping for increasing power capacity, sustaining intensive training periods and, last but not least, as a cosmetic muscle makeover. The aim of this article is to review the biochemistry, physiology and the ergogenic effects of AASs.
Androgen Control of Cell Proliferation and Cytoskeletal Reorganization in Human Fibrosarcoma Cells
Chauhan, Sanjay; Kunz, Susan; Davis, Kelli; Roberts, Jordan; Martin, Greg; Demetriou, Manolis C.; Sroka, Thomas C.; Cress, Anne E.; Miesfeld, Roger L.
2009-01-01
We recently generated an HT-1080-derived cell line called HT-AR1 that responds to dihydrotestosterone (DHT) treatment by undergoing cell growth arrest in association with cytoskeletal reorganization and induction of neuroendocrine-like cell differentiation. In this report, we show that DHT induces a dose-dependent increase in G0/G1 growth-arrested cells using physiological levels of hormone. The arrested cells increase in cell size and contain a dramatic redistribution of desmoplakin, keratin 5, and chromogranin A proteins. DHT-induced cytoskeletal changes were also apparent from time lapse video microscopy that showed that androgen treatment resulted in the rapid appearance of neuronal-like membrane extensions. Expression profiling analysis using RNA isolated from DHT-treated HT-AR1 cells revealed that androgen receptor activation leads to the coordinate expression of numerous cell signaling genes including RhoB, PTGF-β, caveolin-2, Egr-1, myosin 1B, and EHM2. Because RhoB has been shown to have a role in tumor suppression and neuronal differentiation in other cell types, we investigated RhoB signaling functions in the HT-AR1 steroid response. We found that steroid induction of RhoB was DHT-specific and that newly synthesized RhoB protein was post-translationally modified and localized to endocytic vesicles. Moreover, treatment with a farnesyl transferase inhibitor reduced DHT-dependent growth arrest, suggesting that prenylated RhoB might function to inhibit HT-AR1 cell proliferation. This was directly shown by transfecting HT-AR1 cells with RhoB coding sequences containing activating or dominant negative mutations. PMID:14576147
Hews, D K; Abell Baniki, A J
2013-10-01
Acute glucocorticoid elevations can be adaptations to short-term stressors. The breeding season hypothesis predicts reduced glucocorticoid responsiveness to acute stressors in populations or species with short breeding seasons. The striped plateau lizard (Sceloporus virgatus) has a short breeding season in Arizona. We measured plasma corticosterone and total androgen levels (dihydrotestosterone and testosterone) following one of the four stress-handling treatments (0, 10, 60, or 180 min). In both sexes, longer handling stress yielded higher corticosterone; females had higher corticosterone than males at all time points. Androgens did not vary with handling duration, in either sex. Combining treatments, plasma androgens correlated positively with corticosterone (CORT) in females but not in males; plasma CORT and body mass residuals were negatively correlated in both sexes, suggesting lizards in poor body condition and/or not investing heavily in reproduction (follicle mass) have higher acute corticosterone. Total plasma androgens and body mass residuals were positively associated in males, but showed no association in females. The maximal CORT elevation after handling stress in this single-clutching species was of comparable magnitude to responses in related multi-clutching lizard species with longer breeding seasons. Using data from studies of multiple populations of three Sceloporus species, we found no relationship between the relative magnitude of the CORT increase and either latitude or elevation, two variables in the literature correlated with duration of the breeding season, and only weak relationships with geographic elevation and actual (not relative) stress-elevated CORT values in this multi-population comparison.
Wang, Heng; Pu, Yong; Luo, Lei; Li, Yunsheng; Zhang, Yunhai; Cao, Zubing
2018-06-01
Excessive secretion of androgens including androstenedione and testosterone in theca cells frequently causes female infertility in mammals. Melatonin is a potent inhibitor of androgen production in gonadal cells of several species in a membrane receptor-dependent manner. However, the function of melatonin in steroidogenesis of porcine theca cells remains unclear. Here we report that melatonin inhibits androgen biosynthesis independently of its membrane receptors in pigs. Using flow cytometry, immunofluorescence and RT-PCR we showed that the vast majority of cells isolated from the theca layer of antral follicles are indeed theca cells. Furthermore, we demonstrated that of the two of melatonin membrane receptors encoded in the porcine genome, theca cells exclusively express melatonin receptor 1B. Cell counting analysis indicated that different concentrations of melatonin did not alter the normal viability and proliferation of theca cells. Additionally, hormone radioimmunoassay and qPCR respectively showed that a high concentration of melatonin significantly repressed both androgen production and expression of steroidogenic genes involving StAR, CYP11A1, HSD3β and SET (P < 0.05), but did not impair progesterone production. Interestingly, these effects were not reversed by N-acetyl-2-benzyltryptamin, a melatonin membrane receptor antagonist. Overall, these results demonstrate that melatonin inhibits androgen production in porcine theca cells independently of its membrane receptor. Copyright © 2018 Elsevier Inc. All rights reserved.
2014-01-08
Prostate Cancer, Castration Resistant Disease, Hedgehog Signaling, Smoothened, Gli, Cyclopamine, Androgen Signaling, Androgen Biosynthesis, Androgen...role of Hedgehog /Gli Signaling in generating the androgen-independent growth phenotype of castration resistant prostate cancer and will test the ability...of drugs that target Hedgehog /Gli as a means to suppress the androgen independent growth behavior associated with castration resistant prostate
Murga, Jose D; Moorji, Sameer M; Han, Amy Q; Magargal, Wells W; DiPippo, Vincent A; Olson, William C
2015-02-15
Antibody-drug conjugates (ADCs) are an emerging class of cancer therapies that have demonstrated favorable activity both as single agents and as components of combination regimens. Phase 2 testing of an ADC targeting prostate-specific membrane antigen (PSMA) in advanced prostate cancer has shown antitumor activity. The present study examined PSMA ADC used in combination with potent antiandrogens (enzalutamide and abiraterone) and other compounds. Antiproliferative activity and expression of PSMA, prostate-specific antigen and androgen receptor were evaluated in the prostate cancer cell lines LNCaP and C4-2. Cells were tested for susceptibility to antiandrogens or other inhibitors, used alone and in combination with PSMA ADC. Potential drug synergy or antagonism was evaluated using the Bliss independence method. Enzalutamide and abiraterone demonstrated robust, statistically significant synergy when combined with PSMA ADC. Largely additive activity was observed between the antiandrogens and the individual components of the ADC (free drug and unmodified antibody). Rapamycin also synergized with PSMA ADC in certain settings. Synergy was linked in part to upregulation of PSMA expression. In androgen-dependent LNCaP cells, enzalutamide and abiraterone each inhibited proliferation, upregulated PSMA expression, and synergized with PSMA ADC. In androgen-independent C4-2 cells, enzalutamide and abiraterone showed no measurable antiproliferative activity on their own but increased PSMA expression and synergized with PSMA ADC nonetheless. PSMA expression increased progressively over 3 weeks with enzalutamide and returned to baseline levels 1 week after enzalutamide removal. The findings support exploration of clinical treatment regimens that combine potent antiandrogens and PSMA-targeted therapies for prostate cancer. © 2014 Wiley Periodicals, Inc.
Testosterone and Dihydrotestosterone Differentially Improve Cognition in Aged Female Mice
ERIC Educational Resources Information Center
Benice, Ted S.; Raber, Jacob
2009-01-01
Compared with age-matched male mice, female mice experience a more severe age-related cognitive decline (ACD). Since androgens are less abundant in aged female mice compared with aged male mice, androgen supplementation may enhance cognition in aged female mice. To test this, we assessed behavioral performance on a variety of tasks in 22- to…
Scarduzio, Mariangela; Panichi, Roberto; Pettorossi, Vito Enrico; Grassi, Silvarosa
2013-01-01
Estrogenic and androgenic steroids can be synthesised in the brain and rapidly modulate synaptic transmission and plasticity through direct interaction with membrane receptors for estrogens (ERs) and androgens (ARs). We used whole cell patch clamp recordings in brainstem slices of male rats to explore the influence of ER and AR activation and local synthesis of 17β-estradiol (E2) and 5α-dihydrotestosterone (DHT) on the long-term synaptic changes induced in the neurons of the medial vestibular nucleus (MVN). Long-term depression (LTD) and long-term potentiation (LTP) caused by different patterns of high frequency stimulation (HFS) of the primary vestibular afferents were assayed under the blockade of ARs and ERs or in the presence of inhibitors for enzymes synthesizing DHT (5α-reductase) and E2 (P450-aromatase) from testosterone (T). We found that LTD is mediated by interaction of locally produced androgens with ARs and LTP by interaction of locally synthesized E2 with ERs. In fact, the AR block with flutamide prevented LTD while did not affect LTP, and the blockade of ERs with ICI 182,780 abolished LTP without influencing LTD. Moreover, the block of P450-aromatase with letrozole not only prevented the LTP induction, but inverted LTP into LTD. This LTD is likely due to the local activation of androgens, since it was abolished under blockade of ARs. Conversely, LTD was still induced in the presence of finasteride the inhibitor of 5α-reductase demonstrating that T is able to activate ARs and induce LTD even when DHT is not synthesized. This study demonstrates a key and opposite role of sex neurosteroids in the long-term synaptic changes of the MVN with a specific role of T-DHT for LTD and of E2 for LTP. Moreover, it suggests that different stimulation patterns can lead to LTD or LTP by specifically activating the enzymes involved in the synthesis of androgenic or estrogenic neurosteroids. PMID:24265837
Scarduzio, Mariangela; Panichi, Roberto; Pettorossi, Vito Enrico; Grassi, Silvarosa
2013-01-01
Estrogenic and androgenic steroids can be synthesised in the brain and rapidly modulate synaptic transmission and plasticity through direct interaction with membrane receptors for estrogens (ERs) and androgens (ARs). We used whole cell patch clamp recordings in brainstem slices of male rats to explore the influence of ER and AR activation and local synthesis of 17β-estradiol (E2) and 5α-dihydrotestosterone (DHT) on the long-term synaptic changes induced in the neurons of the medial vestibular nucleus (MVN). Long-term depression (LTD) and long-term potentiation (LTP) caused by different patterns of high frequency stimulation (HFS) of the primary vestibular afferents were assayed under the blockade of ARs and ERs or in the presence of inhibitors for enzymes synthesizing DHT (5α-reductase) and E2 (P450-aromatase) from testosterone (T). We found that LTD is mediated by interaction of locally produced androgens with ARs and LTP by interaction of locally synthesized E2 with ERs. In fact, the AR block with flutamide prevented LTD while did not affect LTP, and the blockade of ERs with ICI 182,780 abolished LTP without influencing LTD. Moreover, the block of P450-aromatase with letrozole not only prevented the LTP induction, but inverted LTP into LTD. This LTD is likely due to the local activation of androgens, since it was abolished under blockade of ARs. Conversely, LTD was still induced in the presence of finasteride the inhibitor of 5α-reductase demonstrating that T is able to activate ARs and induce LTD even when DHT is not synthesized. This study demonstrates a key and opposite role of sex neurosteroids in the long-term synaptic changes of the MVN with a specific role of T-DHT for LTD and of E2 for LTP. Moreover, it suggests that different stimulation patterns can lead to LTD or LTP by specifically activating the enzymes involved in the synthesis of androgenic or estrogenic neurosteroids.
Tepavčević, Snežana; Vojnović Milutinović, Danijela; Macut, Djuro; Žakula, Zorica; Nikolić, Marina; Božić-Antić, Ivana; Romić, Snježana; Bjekić-Macut, Jelica; Matić, Gordana; Korićanac, Goran
2014-05-01
It is supposed that women with polycystic ovary syndrome (PCOS) are prone to develop cardiovascular disease as a consequence of multiple risk factors that are mostly related to the state of insulin resistance and consequent hyperinsulinemia. In the present study, we evaluated insulin signaling and glucose transporters (GLUT) in cardiac cells of dihydrotestosterone (DHT) treated female rats as an animal model of PCOS. Expression of proteins involved in cardiac insulin signaling pathways and glucose transporters, as well as their phosphorylation or intracellular localization were studied by Western blot analysis in DHT-treated and control rats. Treatment with DHT resulted in increased body mass, absolute mass of the heart, elevated plasma insulin concentration, dyslipidemia and insulin resistance. At the molecular level, DHT treatment did not change protein expression of cardiac insulin receptor and insulin receptor substrate 1, while phosphorylation of the substrate at serine 307 was increased. Unexpectedly, although expression of downstream Akt kinase and its phosphorylation at threonine 308 were not altered, phosphorylation of Akt at serine 473 was increased in the heart of DHT-treated rats. In contrast, expression and phosphorylation of extracellular signal regulated kinases 1/2 were decreased. Plasma membrane contents of GLUT1 and GLUT4 were decreased, as well as the expression of GLUT4 in cardiac cells at the end of androgen treatment. The obtained results provide evidence for alterations in expression and especially in functional characteristics of insulin signaling molecules and glucose transporters in the heart of DHT-treated rats with PCOS, indicating impaired cardiac insulin action. Copyright © 2014 Elsevier Ltd. All rights reserved.
Perusquía, Mercedes; Greenway, Clayton D.; Perkins, Lisa M.
2015-01-01
Testosterone (TES) and other androgens exert a direct vasorelaxing action on the vasculature in vitro that is structurally specific and independent of cytosolic androgen receptor (AR). The effects of intravenous androgen infusions on mean arterial blood pressure (BP) and heart rate (HR) were determined in conscious, unrestrained, chronically catheterized, ganglionically blocked (hexamethonium, HEX; 30 mg/kg ip) male Sprague-Dawley (SD) and testicular-feminized male (Tfm; AR-deficient) rats, 16–20 wk of age. BP and HR were recorded at baseline and with increasing doses of androgens (0.375–6.00 μmol·kg−1·min−1 iv; 10 min/dose). Data are expressed as means ± SE (n = 5–8 rats/group). In SD rats, baseline BP and HR averaged 103 ± 4 mmHg and 353 ± 12 beats/min (bpm). TES produced a dose-dependent reduction in BP to a low of 87 ± 4 mmHg (Δ16%), while HR was unchanged (354 ± 14 bpm). Neither BP (109 ± 3 mmHg) nor HR (395 ± 13 bpm) were altered by vehicle (10% EtOH in 0.9% saline; 0.15 ml·kg−1·min−1, iv). In Tfm, TES produced a similar reduction in BP (99 ± 3 to 86 ± 3 mmHg, Δ13%); HR was unchanged (369 ± 18 bpm). In SD, 5β-dihydrotestosterone (genomically inactive metabolite) produced a greater reduction in BP than TES (102 ± 2 to 79 ± 2 mmHg, Δ23%); HR was unchanged (361 ± 9). A 20-μg iv bolus of sodium nitroprusside in both SD and Tfm rats reduced BP 30–40 mmHg, while HR was unchanged, confirming blockade by HEX. Pretreatment of SD rats with neuronal nitric oxide synthase (nNOS) inhibitor (S-methyl-thiocitrulline, SMTC; 20 μg·kg−1·min−1 × 30 min) abolished the hypotensive effects of TES infusion on BP (104 ± 2 vs. 101 ± 2 mmHg) and HR (326 ± 11 vs. 324 ± 8 bpm). These data suggest the systemic hypotensive effect of TES and other androgens involves a direct vasodilatory action on the peripheral vasculature which, like the effect observed in isolated arteries, is structurally specific and AR-independent, and involves
In vivo modulation of androgen receptor by androgens.
Kumar, V L; Majumder, P K; Kumar, V
2002-09-01
To study the effect of androgen and antiandrogen on the level of androgen receptor (AR) mRNA. The total RNA was extracted from the prostate and analyzed by slot blot analysis. The blots were hybridized with AR cDNA probe and 1A probe (internal control) and autoradiography was performed. The intensity of signal was measured with a densitometer and the ratio of AR RNA and 1A RNA was calculated. Androgenic deprivation produced by castration decreased the weight of the prostate and increased the levels of AR mRNA. Treatment of the castrated rats with testostrone increased the weight of prostate and decreased the levels of AR mRNA. Treatment of normal rats with flutamide decreased the weight of the gland and increased the levels of AR mRNA. Androgens produce proliferative effect on the prostate and negatively regulate the AR transcription.
Public health impact of androgens.
Kanayama, Gen; Kaufman, Marc J; Pope, Harrison G
2018-06-01
To summarize recent findings regarding the public health impact of androgen abuse. Abuse of androgens (also called 'anabolic-androgenic steroids') has grown into a major worldwide substance abuse problem involving tens of millions of individuals, of whom about 98% are men. Most androgen abusers are still under age 50 today, and thus, the long-term effects of these drugs are only beginning to be understood. Recent studies confirm that long-term supraphysiologic androgen exposure produces cardiovascular toxicity, characterized especially by cardiomyopathy and atherosclerotic disease. Withdrawal from androgens after long-term use may produce prolonged and sometimes irreversible hypogonadism in men. Supraphysiologic androgen levels may sometimes cause irritability, aggressiveness, and violence, whereas androgen withdrawal may cause depression. However, these psychiatric effects are idiosyncratic, affecting only a minority of users. Emerging evidence now also suggests that long-term androgen exposure may cause neurotoxicity, raising the possibility that aging androgen abusers may be at increased risk for dementia. Several recent studies have also described androgen-induced hepatotoxicity, nephrotoxicity, and adverse musculoskeletal effects. Recent studies have demonstrated marked adverse effects of long-term androgen abuse. As increasing numbers of androgen abusers reach middle age, these effects will likely represent an emerging public health problem.
Pham, Steven; Deb, Subrata; Ming, Dong Sheng; Adomat, Hans; Hosseini-Beheshti, Elham; Zoubeidi, Amina; Gleave, Martin; Guns, Emma S Tomlinson
2014-10-01
Castration resistant prostate cancer (CRPC) is often lethal and inevitably develops after androgen ablation therapy. However, in the majority of cases it remains androgen dependent. CRPC tumors have the ability to synthesize their own androgens from cholesterol by engaging in de novo steroidogenesis. We investigated the potential of 22RV1 prostate cancer cells to convert the supplemented steroid precursors within this pathway under the effects of current clinical steroidogenesis inhibitors such as abiraterone and dutasteride, either alone or in combination. Under steroid starved conditions, enzymes responsible for de novo steroidogenesis were upregulated. Testosterone and dihydrotestosterone (DHT) were formed by using both dehydroepiandrosterone (DHEA) and progesterone as substrates. Formation of testosterone and DHT was higher following incubation with DHEA compared to progesterone. Progesterone decreased the mRNA expression of enzymes responsible for steroidogenesis. Abiraterone treatment decreased testosterone production but increased several precursor steroids in both classical and backdoor pathways in the presence of progesterone. In contrast, the DHT levels were elevated following treatment with abiraterone when progesterone was absent. Dutasteride decreased the formation of testosterone, DHT and precursor steroids in the backdoor pathway but increased steroid precursors in the classical steroidogenesis pathway. The combination of abiraterone and dutasteride decreased testosterone and DHT in the presence of progesterone but increased DHT in the absence of progesterone. Abiraterone inhibited androgen receptor (AR) activation but not to the same extent as MDV3100. However, abiraterone and dutasteride treatment, either alone or in combination, were more effective in decreasing prostate specific antigen secretion into the media than MDV3100. Thus, while interventions with these drugs alone or in combination fail to completely inhibit steroidogenesis in the 22RV1
Dissociable Effects on Birdsong of Androgen Signaling in Cortex-Like Brain Regions of Canaries
2017-01-01
The neural basis of how learned vocalizations change during development and in adulthood represents a major challenge facing cognitive neuroscience. This plasticity in the degree to which learned vocalizations can change in both humans and songbirds is linked to the actions of sex steroid hormones during ontogeny but also in adulthood in the context of seasonal changes in birdsong. We investigated the role of steroid hormone signaling in the brain on distinct features of birdsong using adult male canaries (Serinus canaria), which show extensive seasonal vocal plasticity as adults. Specifically, we bilaterally implanted the potent androgen receptor antagonist flutamide in two key brain regions that control birdsong. We show that androgen signaling in the motor cortical-like brain region, the robust nucleus of the arcopallium (RA), controls syllable and trill bandwidth stereotypy, while not significantly affecting higher order features of song such syllable-type usage (i.e., how many times each syllable type is used) or syllable sequences. In contrast, androgen signaling in the premotor cortical-like brain region, HVC (proper name), controls song variability by increasing the variability of syllable-type usage and syllable sequences, while having no effect on syllable or trill bandwidth stereotypy. Other aspects of song, such as the duration of trills and the number of syllables per song, were also differentially affected by androgen signaling in HVC versus RA. These results implicate androgens in regulating distinct features of complex motor output in a precise and nonredundant manner. SIGNIFICANCE STATEMENT Vocal plasticity is linked to the actions of sex steroid hormones, but the precise mechanisms are unclear. We investigated this question in adult male canaries (Serinus canaria), which show extensive vocal plasticity throughout their life. We show that androgens in two cortex-like vocal control brain regions regulate distinct aspects of vocal plasticity. For
Bayen, Stéphane; Gong, Yinhan; Chin, Hong Soon; Lee, Hian Kee; Leong, Yong Eu; Obbard, Jeffrey Philip
2004-01-01
In the last decade, evidence of endocrine disruption in biota exposed to environmental pollutants has raised serious concern. Human cell-based bioassays have been developed to evaluate induced androgenic and estrogenic activities of chemical compounds. However, bioassays have been sparsely applied to environmental samples. In this study we present data on sex hormone activities in the green mussel, Perna viridis, in Singapore’s coastal waters. P. viridis is a common bioindicator of marine contamination, and this study is a follow-up to an earlier investigation that reported the presence of sex hormone activities in seawater samples from Singapore’s coastal environment. Specimens were collected from eight locations around the Singapore coastline and analyzed for persistent organic pollutants (POPs) and heavy metals. Tissue extracts were then screened for activities on androgen receptors (ARs) and estrogen receptors (ER-α and ER-β) using a reporter gene bio-assay based on a HeLa human cell line. Mussel extracts alone did not exhibit AR activity, but in the presence of the reference androgenic hormone dihydrotestosterone (DHT), activities were up to 340% higher than those observed for DHT alone. Peak activities were observed in locations adjacent to industrial and shipping activities. Estrogenic activities of the mussel extract both alone and in the presence of reference hormone were positive. Correlations were statistically investigated between sex hormone activities, levels of pollutants in the mussel tissues, and various biological parameters (specimen size, sex ratio, lipid and moisture content). Significant correlations exist between AR activities, in the presence of DHT, and total concentration of POPs (r = 0.725, p < 0.05). PMID:15531429
Hansen, K A; Tho, S P
1998-01-01
Osteoporosis is one of the most common metabolic bone diseases in the adult population and its prevalence will continue to rise as our population grows older. In both sexes, hypogonadism is associated with accelerated loss of bone and development of osteoporosis. Adrenal and gonadal androgen levels decline with advancing age in both sexes. Androgens act by either directly binding to androgen receptors, or by aromatization of androgens to estrogens and subsequently interacting with estrogen receptors. Both pathways are important for skeletal health. Direct androgen binding to an androgen receptor may play a more important role in early skeletal development and determination of sexual dimorphic traits. While bone remodeling, which is important in maintaining healthy bone through life, is primarily stimulated by estrogen, studies in the rat and human support the complex action of androgens and estrogens in bone modeling and remodeling, and hence the development and maintenance of healthy bone. In postmenopausal females, the addition of androgens to hormone replacement therapy results in significant additional improvement in bone mineral density compared to estrogen replacement alone. Accumulating evidence indicate that androgens play an important role in the health of bone and the potential benefit of adding these agents to hormone replacement regimens.
Dulka, Eden A; Moenter, Suzanne M
2017-11-01
Gonadotropin-releasing hormone (GnRH) neurons regulate reproduction though pulsatile hormone release. Disruption of GnRH release as measured via luteinizing hormone (LH) pulses occurs in polycystic ovary syndrome (PCOS), and in young hyperandrogenemic girls. In adult prenatally androgenized (PNA) mice, which exhibit many aspects of PCOS, increased LH is associated with increased GnRH neuron action potential firing. How GnRH neuron activity develops over the prepubertal period and whether this is altered by sex or prenatal androgen treatment are unknown. We hypothesized GnRH neurons are active before puberty and that this activity is sexually differentiated and altered by PNA. Dams were injected with dihydrotestosterone (DHT) on days 16 to 18 post copulation to generate PNA mice. Action potential firing of GFP-identified GnRH neurons in brain slices from 1-, 2-, 3-, and 4-week-old and adult mice was monitored. GnRH neurons were active at all ages tested. In control females, activity increased with age through 3 weeks, then decreased to adult levels. In contrast, activity did not change in PNA females and was reduced at 3 weeks. Activity was higher in control females than males from 2 to 3 weeks. PNA did not affect GnRH neuron firing rate in males at any age. Short-term action potential patterns were also affected by age and PNA treatment. GnRH neurons are thus typically more active during the prepubertal period than adulthood, and PNA reduces prepubertal activity in females. Prepubertal activity may play a role in establishing sexually differentiated neuronal networks upstream of GnRH neurons; androgen-induced changes during this time may contribute to the adult PNA, and possibly PCOS, phenotype. Copyright © 2017 Endocrine Society.
Zhang, Xuqing; Allan, George F; Tannenbaum, Pamela; Sbriscia, Tifanie; Linton, Olivia; Lai, Muh-Tsann; Haynes-Johnson, Donna; Bhattacharjee, Sheela; Lundeen, Scott G; Sui, Zhihua
2013-03-01
Selective androgen receptor modulators (SARMs) are androgens with tissue-selective activity. SARMs that have anabolic activity on muscle while having minimal stimulatory activity on prostate are classified as SARM agonists. They can be used to prevent the loss of lean body mass that is associated with cancer, immunodeficiency, renal disease and aging. They may also have anabolic activity on bone; thus, unlike estrogens, they may reverse the loss of bone strength associated with aging or hypogonadism. Our in-house effort on SARM program discovers a nonsteroidal androgen receptor ligand with a unique imidazolopyrazole moiety in its structure. In vitro, this compound is a weak androgen receptor binder and a weak androgen agonist. Despite this, in orchidectomized mature rats it is an effective SARM agonist, with an ED(50) on levator ani muscle of 3.3mg/kg and an ED(50) on ventral prostate of >30mg/kg. It has its maximal effect on muscle at the dose of 10mg/kg. In addition, this compound has mixed agonistic and antagonistic activities on prostate, reducing the weight of that tissue in intact rats by 22% at 10mg/kg. The compound does not have significant effect on gonadotropin levels or testosterone levels in both orchidectomized and intact male rats. It does not have notable progestin, estrogen or glucocorticoid agonistic or antagonistic activity in rats. In a female sexual behavior model, it improves the sexual desire of ovariectomized female rats for sexually mature intact males over nonsexually ovariectomized females. Overall, the imidazolopyrazole is a potent prostate-sparing candidate for development as a SARM agonist with an appropriate pharmacological profile for clinical benefit in muscle-wasting conditions and female sexual function disorders. Copyright © 2012 Elsevier Ltd. All rights reserved.
The transcriptional programme of the androgen receptor (AR) in prostate cancer.
Lamb, Alastair D; Massie, Charlie E; Neal, David E
2014-03-01
The androgen receptor (AR) is essential for normal prostate and prostate cancer cell growth. AR transcriptional activity is almost always maintained even in hormone relapsed prostate cancer (HRPC) in the absence of normal levels of circulating testosterone. Current molecular techniques, such as chromatin-immunoprecipitation sequencing (ChIP-seq), have permitted identification of direct AR-binding sites in cell lines and human tissue with a distinct coordinate network evident in HRPC. The effectiveness of novel agents, such as abiraterone acetate (suppresses adrenal androgens) or enzalutamide (MDV3100, potent AR antagonist), in treating advanced prostate cancer underlines the on-going critical role of the AR throughout all stages of the disease. Persistent AR activity in advanced disease regulates cell cycle activity, steroid biosynthesis and anabolic metabolism in conjunction with regulatory co-factors, such as the E2F family, c-Myc and signal transducer and activator of transcription (STAT) transcription factors. Further treatment approaches must target these other factors. © 2013 The Authors. BJU International © 2013 BJU International.
Sartorius, Gideon; Spasevska, Sasa; Idan, Amanda; Turner, Leo; Forbes, Elise; Zamojska, Anna; Allan, Carolyn A; Ly, Lam P; Conway, Ann J; McLachlan, Robert I; Handelsman, David J
2012-11-01
To determine serum concentrations, intra-individual variability and impact of age-related co-morbidities on serum testosterone (T), dihydrotestosterone (DHT), estradiol (E(2)) and estrone (E(1)) in older men. Observational, repeated measures study. Men (n = 325) with 40 years and older self-reporting very good or excellent health. Standardized history, physical examination and collection of nine blood samples at fixed time intervals were measured over 3 months (three at 20 min intervals on days 1 (fasting) and 2 (non-fasting), one at days 7, 30 and 90). Serum T, DHT, E(2) and E(1) (n = 2900, > 99% of scheduled samples) measured by liquid chromatography-tandem mass spectrometry (LC-MS) were analysed by linear mixed model analysis with fasting, age and obesity as covariables. Mean serum T did not vary with age (P = 0·76) but obesity (-0·35 nM per body mass index (BMI) unit, P < 0·0001) and ex-smoker status (-1·6 nM, P < 0·001) had significant effects. Serum DHT was increased with age (+0·011 nM per year, P = 0·001) but decreased with obesity (-0·05 nM per BMI unit, P < 0·0001). Serum E(2) did not vary with age (P = 0·31) or obesity (P = 0·12). Overnight fasting increased (by 9-16%, all P < 0·001) and reduced variability in morning serum T, DHT, E(2) and E(1). Non-fasting serum T and DHT were stable over time (day, week, month or 3 months; P > 0·28). Serum T, DHT and E(2) displayed no decrease associated with age among men over 40 years of age who self-report very good or excellent health although obesity and ex-smoking status were associated with decreased serum androgens (T and DHT) but not E(2). These findings support the interpretation that the age-related decline in blood T accompanying non-specific symptoms in older men may be due to accumulating age-related co-morbidities rather than a symptomatic androgen deficiency state. © 2012 Blackwell Publishing Ltd.
Androgen-Induced Cell Migration: Role of Androgen Receptor/Filamin A Association
Castoria, Gabriella; D'Amato, Loredana; Ciociola, Alessandra; Giovannelli, Pia; Giraldi, Tiziana; Sepe, Leandra; Paolella, Giovanni; Barone, Maria Vittoria; Migliaccio, Antimo; Auricchio, Ferdinando
2011-01-01
Background Androgen receptor (AR) controls male morphogenesis, gametogenesis and prostate growth as well as development of prostate cancer. These findings support a role for AR in cell migration and invasiveness. However, the molecular mechanism involved in AR-mediated cell migration still remains elusive. Methodology/Principal Findings Mouse embryo NIH3T3 fibroblasts and highly metastatic human fibrosarcoma HT1080 cells harbor low levels of transcriptionally incompetent AR. We now report that, through extra nuclear action, AR triggers migration of both cell types upon stimulation with physiological concentrations of the androgen R1881. We analyzed the initial events leading to androgen-induced cell migration and observed that challenging NIH3T3 cells with 10 nM R1881 rapidly induces interaction of AR with filamin A (FlnA) at cytoskeleton. AR/FlnA complex recruits integrin beta 1, thus activating its dependent cascade. Silencing of AR, FlnA and integrin beta 1 shows that this ternary complex controls focal adhesion kinase (FAK), paxillin and Rac, thereby driving cell migration. FAK-null fibroblasts migrate poorly and Rac inhibition by EHT impairs motility of androgen-treated NIH3T3 cells. Interestingly, FAK and Rac activation by androgens are independent of each other. Findings in human fibrosarcoma HT1080 cells strengthen the role of Rac in androgen signaling. The Rac inhibitor significantly impairs androgen-induced migration in these cells. A mutant AR, deleted of the sequence interacting with FlnA, fails to mediate FAK activation and paxillin tyrosine phosphorylation in androgen-stimulated cells, further reinforcing the role of AR/FlnA interaction in androgen-mediated motility. Conclusions/Significance The present report, for the first time, indicates that the extra nuclear AR/FlnA/integrin beta 1 complex is the key by which androgen activates signaling leading to cell migration. Assembly of this ternary complex may control organ development and prostate cancer
Karlsson, Teresa; Vahlquist, Anders; Kedishvili, Natalia; Törmä, Hans
2003-03-28
Retinol dehydrogenase-4 (RoDH-4) converts retinol and 13-cis-retinol to corresponding aldehydes in human liver and skin in the presence of NAD(+). RoDH-4 also converts 3 alpha-androstanediol and androsterone into dihydrotestosterone and androstanedione, which may stimulate sebum secretion. This oxidative 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) activity of RoDH-4 is competitively inhibited by retinol and 13-cis-retinol. Here, we further examine the substrate specificity of RoDH-4 and the inhibition of its 3 alpha-HSD activity by retinoids. Recombinant RoDH-4 oxidized 3,4-didehydroretinol-a major form of vitamin A in the skin-to its corresponding aldehyde. 13-cis-retinoic acid (isotretinoin), 3,4-didehydroretinoic acid, and 3,4-didehydroretinol, but not all-trans-retinoic acid or the synthetic retinoids acitretin and adapalene, were potent competitive inhibitors of the oxidative 3 alpha-HSD activity of RoDH-4, i.e., reduced the formation of dihydrotestosterone and androstandione in vitro. Extrapolated to the in vivo situation, this effect might explain the unique sebosuppressive effect of isotretinoin when treating acne.
Caraci, Filippo; Pistarà, V; Corsaro, A; Tomasello, Flora; Giuffrida, Maria Laura; Sortino, Maria Angela; Nicoletti, Ferdinando; Copani, Agata
2011-04-01
Anabolic-androgenic steroid (AAS) abuse is associated with multiple neurobehavioral disturbances. The sites of action and the neurobiological sequels of AAS abuse are unclear at present. We investigated whether two different AASs, nandrolone and methandrostenolone, could affect neuronal survival in culture. The endogenous androgenic steroid testosterone was used for comparison. Both testosterone and nandrolone were neurotoxic at micromolar concentrations, and their effects were prevented by blockade of androgen receptors (ARs) with flutamide. Neuronal toxicity developed only over a 48-hr exposure to the steroids. The cell-impermeable analogues testosterone-BSA and nandrolone-BSA, which preferentially target membrane-associated ARs, were also neurotoxic in a time-dependent and flutamide-sensitive manner. Testosterone-BSA and nandrolone-BSA were more potent than their parent compounds, suggesting that membrane-associated ARs were the relevant sites for the neurotoxic actions of the steroids. Unlike testosterone and nandrolone, toxicity by methandrostenolone and methandrostenolone-BSA was insensitive to flutamide, but it was prevented by the glucocorticoid receptor (GR) antagonist RU-486. Methandrostenolone-BSA was more potent than the parent compound, suggesting that its toxicity relied on the preferential activation of putative membrane-associated GRs. Consistently with the evidence that membrane-associated GRs can mediate rapid effects, a brief challenge with methandrostenolone-BSA was able to promote neuronal toxicity. Activation of putative membrane steroid receptors by nontoxic (nanomolar) concentrations of either nandrolone-BSA or methandrostenolone-BSA became sufficient to increase neuronal susceptibility to the apoptotic stimulus provided by β-amyloid (the main culprit of AD). We speculate that AAS abuse might facilitate the onset or progression of neurodegenerative diseases not usually linked to drug abuse. Copyright © 2011 Wiley-Liss, Inc.
Soekmadji, Carolina; Riches, James D.; Russell, Pamela J.; Ruelcke, Jayde E.; McPherson, Stephen; Wang, Chenwei; Hovens, Chris M.; Corcoran, Niall M.; Hill, Michelle M.; Nelson, Colleen C.
2017-01-01
Proliferation and maintenance of both normal and prostate cancer (PCa) cells is highly regulated by steroid hormones, particularly androgens, and the extracellular environment. Herein, we identify the secretion of CD9 positive extracellular vesicles (EV) by LNCaP and DUCaP PCa cells in response to dihydrotestosterone (DHT) and use nano-LC–MS/MS to identify the proteins present in these EV. Subsequent bioinformatic and pathway analyses of the mass spectrometry data identified pathologically relevant pathways that may be altered by EV contents. Western blot and CD9 EV TR-FIA assay confirmed a specific increase in the amount of CD9 positive EV in DHT-treated LNCaP and DUCaP cells and treatment of cells with EV enriched with CD9 after DHT exposure can induce proliferation in androgen-deprived conditions. siRNA knockdown of endogenous CD9 in LNCaPs reduced cellular proliferation and expression of AR and prostate specific antigen (PSA) however knockdown of AR did not alter CD9 expression, also implicating CD9 as an upstream regulator of AR. Moreover CD9 positive EV were also found to be significantly higher in plasma from prostate cancer patients in comparison with benign prostatic hyperplasia patients. We conclude that CD9 positive EV are involved in mediating paracrine signalling and contributing toward prostate cancer progression. PMID:28881726
Ricci, Lesley A.; Morrison, Thomas R.; Melloni, Richard H.
2014-01-01
In the U.S. and worldwide anabolic/androgenic steroid use remains high in the adolescent population. This is concerning given that anabolic/androgenic steroid use is associated with a higher incidence of aggressive behavior during exposure and anxiety during withdrawal. This study uses pubertal Syrian hamsters (Mesocricetus auratus) to investigate the hypothesis that an inverse behavioral relationship exists between anabolic/androgenic steroid-induced aggression and anxiety across adolescent exposure and withdrawal. In the first experiment, we examined aggression and anxiety during adolescent anabolic/androgenic steroid exposure and withdrawal. Adolescent anabolic/androgenic steroid administration produced significant increases in aggression and decreases in anxiety during the exposure period followed by significant decreases in aggression and increases in anxiety during anabolic/androgenic steroid withdrawal. In a second experiment, anabolic/androgenic steroid exposed animals were separated into groups based on their aggressive response during the exposure period and then tested for anxiety during exposure and then for both aggression and anxiety during withdrawal. Data were analyzed using a within subjects repeated measures predictive analysis. Linear regression analysis revealed that the difference in aggressive responding between the anabolic/androgenic steroid exposure and withdrawal periods was a significant predictor of differences in anxiety for both days of testing. Moreover, the combined data suggest that the decrease in aggressive behavior from exposure to withdrawal predicts an increase in anxiety-like responding within these same animals during this time span. Together these findings indicate that early anabolic/androgenic steroid exposure has potent aggression- and anxiety- eliciting effects and that these behavioral changes occur alongside a predictive relationship that exists between these two behaviors over time. PMID:24126136
MOMOZONO, HIROYUKI; MIYAKE, HIDEAKI; TEI, HIROMOTO; HARADA, KEN-ICHI; FUJISAWA, MASATO
2016-01-01
The present study aimed to investigate the significance of anti-androgen withdrawal and/or subsequent alternative anti-androgen therapy in patients with advanced prostate cancer (PC) who relapsed after initial maximum androgen blockade (MAB). The present study evaluated the clinical outcomes of 272 consecutive advanced PC patients undergoing anti-androgen withdrawal and/or subsequent alternative anti-androgen therapy with flutamide following the failure of initial MAB using bicalutamide. With the exception of 41 patients (15.1%) who did not undergo anti-androgen withdrawal due to the characteristics of PC suggesting aggressive diseases, prostate-specific antigen (PSA) declined from the baseline value in 83 patients (35.9%), including 18 (7.8%) with PSA decline >50%, but not in the remaining 148 (64.1%). No significant difference in the overall survival (OS) or cancer-specific survival (CSS) among the three groups was observed based on the response to anti-androgen withdrawal. Following the introduction of alternative anti-androgen therapy with flutamide, PSA decline was observed in 185 patients (68.0%), including 103 (37.9%) who achieved a PSA reduction of >50%; however, the PSA level continued to elevate in the remaining 87 (32.0%). Furthermore, of the numerous factors examined, only the duration of the initial MAB therapy was shown to be significantly correlated with the PSA decline following alternative anti-androgen therapy. Multivariate analysis of several factors identified revealed that only PSA decline following alternative anti-androgen therapy was an independent predictor of CSS and OS. If initial MAB is effective, the introduction of alternative anti-androgen therapy may be considered; however, anti-androgen withdrawal should be omitted, irrespective of the characteristics of advanced PC. PMID:27123292
Roelofs, Maarke J E; Temming, A Roberto; Piersma, Aldert H; van den Berg, Martin; van Duursen, Majorie B M
2014-01-01
Conazole fungicides are widely used in agriculture despite their suspected endocrine disrupting properties. In this study, the potential (anti-)androgenic effects of ten conazoles were assessed and mutually compared with existing data. Effects of cyproconazole (CYPRO), fluconazole (FLUC), flusilazole (FLUS), hexaconazole (HEXA), myconazole (MYC), penconazole (PEN), prochloraz (PRO), tebuconazole (TEBU), triadimefon (TRIA), and triticonazole (TRIT) were examined using murine Leydig (MA-10) cells and human T47D-ARE cells stably transfected with an androgen responsive element and a firefly luciferase reporter gene. Six conazoles caused a decrease in basal testosterone (T) secretion by MA-10 cells varying from 61% up to 12% compared to vehicle-treated control. T secretion was concentration-dependently inhibited after exposure of MA-10 cells to several concentrations of FLUS (IC 50 = 12.4 μM) or TEBU (IC 50 = 2.4 μM) in combination with LH. The expression of steroidogenic and cholesterol biosynthesis genes was not changed by conazole exposure. Also, there were no changes in reactive oxygen species (ROS) formation that could explain the altered T secretion after exposure to conazoles. Nine conazoles decreased T-induced AR activation (IC 50 s ranging from 10.7 to 71.5 μM) and effect potencies (REPs) were calculated relative to the known AR antagonist flutamide (FLUT). FLUC had no effect on AR activation by T. FLUS was the most potent (REP = 3.61) and MYC the least potent (REP = 0.03) AR antagonist. All other conazoles had a comparable REP from 0.12 to 0.38. Our results show distinct in vitro anti-androgenic effects of several conazole fungicides arising from two mechanisms: inhibition of T secretion and AR antagonism, suggesting potential testicular toxic effects. These effects warrant further mechanistic investigation and clearly show the need for accurate exposure data in order to perform proper (human) risk assessment of this class of compounds.
Progesterone potentially degrades to potent androgens in surface waters.
Ojoghoro, Jasper O; Chaudhary, Abdul J; Campo, Pablo; Sumpter, John P; Scrimshaw, Mark D
2017-02-01
Progesterone is a natural hormone, excreted in higher concentrations than estrogens, and has been detected in the aqueous environment. As with other compounds, it is transformed during wastewater treatment processes and in the environment. However, minor modifications to the structure may result in transformation products which still exhibit biological activity, so understanding what transformation products are formed is of importance. The current study was undertaken to identify putative transformation products resulting from spiking river water with progesterone in a laboratory-based degradation study and hence to follow the metabolic breakdown pathways. On the basis of literature reports and predictions from the EAWAG Biocatalysis/biodegradation database, target putative transformation products were initially monitored under unit resolution mass spectrometry. The identity of these transformation products was confirmed by using accurate-mass quadrupole time-of-flight. The study results highlight that transformation of progesterone can potentially create other classes of steroids, some of which may still be potent, and possess other types of biological activity. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.
Magri, María Laura; Gottardo, María Florencia; Zárate, Sandra; Eijo, Guadalupe; Ferraris, Jimena; Jaita, Gabriela; Ayala, Mariela Moreno; Candolfi, Marianela; Pisera, Daniel; Seilicovich, Adriana
2016-03-01
Hormones locally synthesized in the anterior pituitary gland are involved in regulation of pituitary cell renewal. In the pituitary, testosterone (T) may exert its actions per se or by conversion to dihydrotestosterone (DHT) or 17β-estradiol (E2) by 5α-reductase and aromatase activity, which are expressed in this gland. Previous reports from our laboratory showed that estrogens modulate apoptosis of lactotropes and somatotropes from female rats. Now, we examined the in vitro and in vivo effects of gonadal steroids on apoptosis of anterior pituitary cells from adult male rats. T in vitro did not modify apoptosis in anterior pituitary cells from gonadectomized (GNX) male rats. DHT, a non-aromatizable androgen, exerted direct antiapoptotic action on total anterior pituitary cells and folliculo-stellate cells, but not on lactotropes, somatotropes, or gonadotropes. On the contrary, E2 exerted a rapid apoptotic effect on total cells as well as on lactotropes and somatotropes. Incubation of anterior pituitary cells with T in presence of Finasteride, an inhibitor of 5α-reductase, increased the percentage of TUNEL-positive cells. In vivo administration of DHT to GNX rats reduced apoptosis in the anterior pituitary whereas E2 exerted proapoptotic action and reduced cells in G2/M-phase of the cell cycle. In summary, our results indicate that DHT and E2 have opposite effects on apoptosis in the anterior pituitary gland suggesting that local metabolization of T to these steroids could be involved in pituitary cell turnover in males. Changes in expression and/or activity of 5α-reductase and aromatase may play a role in the development of anterior pituitary tumors.
Prenatal androgen excess enhances stimulation of the GNRH pulse in pubertal female rats.
Yan, Xiaonan; Yuan, Chun; Zhao, Nannan; Cui, Yugui; Liu, Jiayin
2014-07-01
In adolescent girls with polycystic ovary syndrome (PCOS), neuroendocrine derangements manifest after the onset of puberty, characterized by rapid LH pulse frequency. The early mechanism underlying the pubertal regulation of the GNRH/LH pulsatile release in adolescents with PCOS remains uncertain. To determine the effects of prenatal androgen exposure on the activation of GNRH neurons and generation of LH pulse at puberty, we administrated 5α-dihydrotestosterone to pregnant rats and observed serum LH levels and expression of hypothalamic genes in female offspring from postnatal 4 to 8 weeks. The 6-week-old prenatally androgenized (PNA) female rats exhibited an increase in LH pulse frequency. The hypothalamic expression of neurokinin B (Nkb (Tac2)) and Lepr mRNA levels in PNA rats increased remarkably before puberty and remained high during puberty, whereas elevated Kiss1 mRNA levels were detected only after the onset of puberty. Exogenous kisspeptin, NK3R agonist, and leptin triggered tonic stimulation of GNRH neurons and increased LH secretion in 6-week-old PNA rats. Leptin upregulated Kiss1 mRNA levels in the hypothalamus of pubertal PNA rats; however, pretreatment with a kisspeptin antagonist failed to suppress the elevated serum LH stimulated by leptin, indicating that the stimulatory effects of leptin may be conveyed indirectly to GNRH neurons via other neural components within the GNRH neuronal network, rather than through the kisspeptin-GPR54 pathway. These findings validate the hypotheses that NKB and leptin play an essential role in the activation of GNRH neurons and initiation of increased LH pulse frequency in PNA female rats at puberty and that kisspeptin may coordinate their stimulatory effects on LH release. © 2014 Society for Endocrinology.
Androgen abuse in the community.
Melnik, Bodo C
2009-06-01
To provide information of the current prevalence of illicit use of androgens by individuals of the community. Prevalence of abuse of androgens in individuals of the general population has reached alarming dimensions. Use of androgens is no longer limited to competitive sports, but has spread to leisure and fitness sports, bodybuilding, and nonathletes motivated to increase muscular mass and physical attractiveness. Alarming studies from Germany demonstrated that members of the healthcare systems provide illegal androgens to 48.1% of abusers visiting fitness centers. The new trend to combine androgens with growth hormone, insulin, and insulinotropic milk protein-fortified drinks may potentiate health risks of androgen abuse. The use of androgens has changed from being a problem restricted to sports to one of public health concern. The potential health hazards of androgen abuse are underestimated in the medical community, which unfortunately contributes to illegal distribution of androgens. Both the adverse effects of current androgen abuse especially in young men as well as the chronic toxicity from past long-term abuse of now middle-aged men has to be considered as a growing public health problem. In the future, an increasing prevalence of androgen misuse in combination with other growth-promoting hormones and insulinotropic milk protein products has to be expected, which may have further promoting effects on the prevalence of chronic western diseases.
Human androgen deficiency: insights gained from androgen receptor knockout mouse models
Rana, Kesha; Davey, Rachel A; Zajac, Jeffrey D
2014-01-01
The mechanism of androgen action is complex. Recently, significant advances have been made into our understanding of how androgens act via the androgen receptor (AR) through the use of genetically modified mouse models. A number of global and tissue-specific AR knockout (ARKO) models have been generated using the Cre-loxP system which allows tissue- and/or cell-specific deletion. These ARKO models have examined a number of sites of androgen action including the cardiovascular system, the immune and hemopoetic system, bone, muscle, adipose tissue, the prostate and the brain. This review focuses on the insights that have been gained into human androgen deficiency through the use of ARKO mouse models at each of these sites of action, and highlights the strengths and limitations of these Cre-loxP mouse models that should be considered to ensure accurate interpretation of the phenotype. PMID:24480924
Androgen Receptor (AR) in Cardiovascular Diseases
Huang, Chiung-Kuei; Lee, Soo Ok; Chang, Eugene; Pang, Haiyan; Chang, Chawnshang
2016-01-01
Cardiovascular diseases (CVDs) are still the highest leading cause of death worldwide. Several risk factors have been linked to CVDs, including smoking, diabetes, hyperlipidemia, and gender among others. Sex hormones, especially the androgen and its receptor, androgen receptor (AR), have been linked to many diseases with a clear gender difference. Here, we summarize androgen/AR effects on CVDs, including hypertension, stroke, atherosclerosis, abdominal aortic aneurysm (AAA), myocardial hypertrophy, and heart failure, as well as metabolic syndrome/diabetes and their impacts on CVDs. Androgen/AR signaling exacerbates hypertension and anti-androgens may suppress hypertension. Androgen/AR signaling plays dual roles in strokes, depending on different kinds of factors, but generally males have a higher incidence of strokes than females. Androgen and AR differentially modulate atherosclerosis. Androgen deficiency causes elevated lipid accumulation to enhance atherosclerosis, but targeting AR in selective cells without altering serum androgen levels would suppress atherosclerosis progression. Androgen/AR signaling is crucial in AAA development and progression, and targeting androgen/AR profoundly restricts AAA progression. Men have increased cardiac hypertrophy as compared to age-matched women that may be due to androgens. Finally, androgen/AR plays important roles in contributing to obesity and insulin/leptin resistance to increase the metabolic syndrome. PMID:26769913
Ebeling, Peter R
2010-06-01
The review is timely given recent advances regarding mechanisms of androgen action on bone cells and in humans. Osteoporosis in men is an important public health problem. An improved understanding of the role of androgens in the pathophysiology of bone loss will lead to new treatments. Androgen receptors are present in most bone cells. Testosterone acts on bone both directly via the androgen receptor and indirectly, following aromatization, via the oestrogen receptor. During skeletal modelling, ERalpha is critical for longitudinal bone growth. For periosteal growth and bone expansion, androgen receptor activation has a positive effect, whereas ERalpha activation is inhibitory. During skeletal remodelling, both receptor pathways generate similar and additive effects on bone.Androgen deficiency is a common secondary cause of osteoporosis in men and should be treated with testosterone, particularly in symptomatic men. However, lack of efficacy data for testosterone in osteoporosis means it is less useful as a first-line treatment in men with age-related declines in testosterone and osteoporosis, when other agents such as bisphosphonates and parathyroid hormone are effective. Randomized, placebo-controlled trials of testosterone therapy in men with age-related declines in testosterone and osteoporosis are needed, and should carefully evaluate potential risks, as well as its efficacy in reducing fractures and other health benefits.
Bahashwan, Saleh A.; Fayed, Ahmed A.; Ramadan, Mohamed A.; Amr, Abd El-Galil E.; Al-Harbi, Naif O.
2014-01-01
A series of substituted pyrazole, triazole and thiazole derivatives (2–13) were synthesized from 1-(naphtho[1,2-d]thiazol-2-yl)hydrazine as starting material and evaluated as androgen receptor antagonists and anti-prostate cancer agents. The newly synthesized compounds showed potent androgen receptor antagonists and anti-prostate cancer activities with low toxicity (lethal dose 50 (LD50)) comparable to Bicalutamide as reference drug. The structures of newly synthesized compounds were confirmed by IR, 1H-NMR, 13C-NMR, and MS spectral data and elemental analysis. The detailed synthesis, spectroscopic data, LD50 values and pharmacological activities of the synthesized compounds are reported. PMID:25421248
Estrogen induces androgen-repressed SOX4 expression to promote progression of prostate cancer cells.
Yang, Muyi; Wang, Jing; Wang, Lin; Shen, Chengwu; Su, Bo; Qi, Mei; Hu, Jing; Gao, Wei; Tan, Weiwei; Han, Bo
2015-09-01
The sex determing region Y-box 4 (SOX4) gene is a critical developmental transcriptional factor that is overexpressed in prostate cancer (PCa). While we and others have investigated the role of SOX4 overexpression in PCa, the molecular mechanism underlying its aberrant expression remains unclear. Immunohistochemistry were utilized to detect SOX4 expression and the correlation between estrogen receptor β (ERβ), androgen receptor (AR) and SOX4 in a cohort of 94 clinical specimens. Real-time quantitative PCR and Western blotting were used to study the transcript and protein expression levels. Immunofluorescence staining and co-immunoprecipitation were performed to assess the interaction and subcellular location of ERβ and AR. Chromatin immunoprecipitation (ChIP) assays and Luciferase reporter assays were performed to explore the binding and transcriptional activities of ERβ and AR to the SOX4 promoter. Cellular function was evaluated by MTS, invasion and wound healing assays. SOX4 expression is up-regulated in Castration-Resistant Prostate Cancer (CRPC) tumors compared to hormone-dependent PCa (HDPC) cases. Increased expression was also observed in PCa cells after long-term androgen-deprivation treatment (ADT). In vitro data indicated that SOX4 is an AR transcriptional target and down-regulated by dihydrotestosterone (DHT) via AR. 17β-estradiol (E2) up-regulates SOX4 expression in the absence of androgen through the formation of a protein complex between ERβ and AR. Knockdown of AR or ERβ blocks the E2-induced SOX4 expression. ChIP assays confirmed that both ERβ and AR bind to the SOX4 promoter in response to E2. Functionally, silencing SOX4 significantly attenuates the proliferative effect, as well as the capacity of migration and invasion of E2 on PCa cells. Clinically, overexpression of SOX4 is significantly associated with ERβ expression in PCa. In addition, this association is still retained in CRPC patients with poor prognosis. These findings suggest
Komura, Kazumasa; Jeong, Seong Ho; Hinohara, Kunihiko; Qu, Fangfang; Wang, Xiaodong; Hiraki, Masayuki; Azuma, Haruhito; Lee, Gwo-Shu Mary; Kantoff, Philip W.; Sweeney, Christopher J.
2016-01-01
The androgen receptor (AR) plays an essential role in prostate cancer, and suppression of its signaling with androgen deprivation therapy (ADT) has been the mainstay of treatment for metastatic hormone-sensitive prostate cancer for more than 70 y. Chemotherapy has been reserved for metastatic castration-resistant prostate cancer (mCRPC). The Eastern Cooperative Oncology Group-led trial E3805: ChemoHormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease in Prostate Cancer (CHAARTED) showed that the addition of docetaxel to ADT prolonged overall survival compared with ADT alone in patients with metastatic hormone-sensitive prostate cancer. This finding suggests that there is an interaction between AR signaling activity and docetaxel sensitivity. Here we demonstrate that the prostate cancer cell lines LNCaP and LAPC4 display markedly different sensitivity to docetaxel with AR activation, and RNA-seq analysis of these cell lines identified KDM5D (lysine-specific demethylase 5D) encoded on the Y chromosome as a potential mediator of this sensitivity. Knocking down KDM5D expression in LNCaP leads to docetaxel resistance in the presence of dihydrotestosterone. KDM5D physically interacts with AR in the nucleus, and regulates its transcriptional activity by demethylating H3K4me3 active transcriptional marks. Attenuating KDM5D expression dysregulates AR signaling, resulting in docetaxel insensitivity. KDM5D deletion was also observed in the LNCaP-derived CRPC cell line 104R2, which displayed docetaxel insensitivity with AR activation, unlike parental LNCaP. Dataset analysis from the Oncomine database revealed significantly decreased KDM5D expression in CRPC and poorer prognosis with low KDM5D expression. Taking these data together, this work indicates that KDM5D modulates the AR axis and that this is associated with altered docetaxel sensitivity. PMID:27185910
McCormick, David L; Johnson, William D; Kozub, Nicole M; Rao, K V N; Lubet, Ronald A; Steele, Vernon E; Bosland, Maarten C
2007-02-01
Dehydroepiandrosterone (DHEA) is a potent inhibitor of prostate carcinogenesis in rats. However, concerns related to the possible androgenicity of DHEA may preclude its use for chemoprevention of human prostate cancer. Studies were performed to compare the androgenicity of DHEA and a fluorinated DHEA analog, 16alpha-fluoro-5-androsten-17-one (fluasterone), and to determine the chemopreventive activity of fluasterone in the rat prostate. Comparisons of accessory sex gland weight and histology in gonadectomized male rats demonstrated that fluasterone is less androgenic than is DHEA. Fluasterone conferred significant protection against prostate carcinogenesis induced in Wistar-Unilever rats by a sequential regimen of N-methyl-N-nitrosourea+testosterone. Chronic administration of fluasterone at levels of 2000 and 1000 mg/kg diet reduced the incidence of adenocarcinoma in the dorsolateral/anterior prostate from 64% in dietary controls to 28 and 31%, respectively. Other than a dose-related suppression of body weight gain, chronic exposure to fluasterone induced no clinical evidence of toxicity; suppression of body weight gain may be either a pharmacological effect or a minimally toxic effect of the compound. These data demonstrate that a minimally androgenic analog of DHEA protects against prostate carcinogenesis induced in rats by a chemical carcinogen + androgen. The reduced androgenicity of fluasterone may obviate toxicities associated with the androgenicity of the parent compound. On this basis, fluasterone merits consideration for evaluation in clinical trials for prostate cancer prevention. The chemopreventive activity of a non-androgenic DHEA analog suggests that at least a portion of the chemopreventive activity of DHEA in the rat prostate is unrelated to hormonal effects.
Hsieh, Chen-Lin; Cai, Changmeng; Giwa, Ahmed; Bivins, Aaronica; Chen, Shao-Yong; Sabry, Dina; Govardhan, Kumara; Shemshedini, Lirim
2008-07-01
Cellular changes that affect the androgen receptor (AR) can cause prostate cancer to transition from androgen dependent to androgen independent, which is usually lethal. One common change in prostate tumors is overexpression of the AR, which has been shown to lead to androgen-independent growth of prostate cancer cells. This led us to hypothesize that expression of a hyperactive AR would be sufficient for androgen-independent growth of prostate cancer cells. To test this hypothesis, stable lune cancer prostate (LNCaP) cell lines were generated, which express a virion phosphoprotein (VP)16-AR hybrid protein that contains full-length AR fused to the strong viral transcriptional activation domain VP16. This fusion protein elicited as much as a 20-fold stronger transcriptional activity than the natural AR. Stable expression of VP16-AR in LNCaP cells yielded androgen-independent cell proliferation, while under the same growth conditions the parental LNCaP cells exhibited only androgen-dependent growth. These results show that expression of a hyperactive AR is sufficient for androgen-independent growth of prostate cancer cells. To study the molecular basis of this enhanced growth, we measured the expression of soluble guanylyl cyclase-alpha1 (sGCalpha1), a subunit of the sGC, an androgen-regulated gene that has been shown to be involved in prostate cancer cell growth. Interestingly, the expression of sGCalpha1 is androgen independent in VP16-AR-expressing cells, in contrast to its androgen-induced expression in control LNCaP cells. RNA(I)-dependent inhibition of sGCalpha1 expression resulted in significantly reduced proliferation of VP16-AR cells, implicating an important role for sGCalpha1 in the androgen-independent growth of these cells.
Expanding the therapeutic use of androgens via selective androgen receptor modulators (SARMs)
Gao, Wenqing; Dalton, James T.
2007-01-01
Selective androgen receptor modulators (SARMs) are a novel class of androgen receptor (AR) ligands that might change the future of androgen therapy dramatically. With improved pharmacokinetic characteristics and tissue-selective pharmacological activities, SARMs are expected to greatly extend the clinical applications of androgens to osteoporosis, muscle wasting, male contraception and diseases of the prostate. Mechanistic studies with currently available SARMs will help to define the contributions of differential tissue distribution, tissue-specific expression of 5α-reductase, ligand-specific regulation of gene expression and AR interactions with tissue-specific coactivators to their observed tissue selectivity, and lead to even greater expansion of selective anabolic therapies. PMID:17331889
Shulman, L P
2009-12-01
The cessation of ovarian sex steroidigenesis, either as result as surgical extirpation, certain medical therapies or the gradual cessation of ovarian function, leads to menopause with all its associated physiological, physical and lifestyle changes. The changing hormonal milieu of menopause is most commonly associated with declining levels of estrogens. However, ovarian senescence also results in declining levels of androgens. Indeed, it is the loss of physiological levels of estrogens and androgens that result in the varied signs and symptoms of menopause including vasomotor symptoms, bone mineral density loss, reduced interest in sex, alterations in mood and energy and hair loss, among others. This paper will provide a review of the role of androgens in the menopause and assess the potential of androgen therapies in the management of the menopause.
Androgens: basic biology and clinical implication.
Orwoll, E S
2001-10-01
Although androgens have been considered essential modulators of bone biology in men, recent studies have indicated that estrogen may have an important, if not dominant, role. Nevertheless, there is strong evidence that androgens have independent skeletal actions. Nonaromatizable androgens influence a variety of aspects of bone cell biology and are capable of modulating bone remodeling and bone mass. It appears that androgens are particularly important in the control of periosteal bone formation, an effect that might underlie the gender difference in bone size. Alterations in androgen receptor function affect bone metabolism, and new information suggests that androgens modulate receptor homeostasis. The clinical implications of androgen effects, and how they interact with those of estrogens, are somewhat unclear. It is likely that overall bone homeostasis and gender differences depend on a combination of androgenic and estrogenic actions. Androgens may well provide advantages in the prevention and therapy of metabolic bone disorders in both men and women.
[Nipple dysplasia and androgen syndrome].
Radowicki, S; Koczorowski, R
1997-11-01
Among 1500 patients in the reproductive age of Clinical Department of Endocrinological Gynecology in State Hospital in Warszawa, Poland estimated the correlations between the onset of benign breast disease (BBD) and the incidence of androgenic syndrome. Symptoms of the androgenic syndrome stated in cases of 191 women; 51 of them had also benign lesions of the breasts. It makes 26.9 percent women with the symptoms of androgenicity. Clinical studies have correlated mean age patients with acne, hirsutism, menstrual cycle disturbances, gain of weight (androgenic syndrome) and mean age women who have suffered both androgenicity and BBD.
Schayek, Hagit; Seti, Hila; Greenberg, Norman M; Sun, Shihua; Werner, Haim; Plymate, Stephen R
2010-07-29
The progression of prostate cancer from an organ-confined, androgen-sensitive disease to a metastatic one is associated with dysregulation of androgen receptor (AR)-regulated target genes and with a decrease in insulin-like growth factor-I receptor (IGF-IR) expression. To investigate the differential effects of wild type (wt) and mutant AR on IGF-IR levels we employed a series of isogenic prostate-derived cell lines and human xenografts. We show that basal and phosphorylated IGF-IR levels progressively decreased as prostate cancer cells became more tumorigenic and metastatic. In addition, we show that wt, but not mutant, AR along with dihydrotestosterone treatment increased IGF-IR promoter activity and endogenous IGF-IR levels. ChIP analysis show enhanced AR binding to the IGF-IR promoter in AR-overexpressing cells. Finally, wt AR-overexpressing cells display an enhanced proliferation rate. In summary, we provide evidence that activated wt AR enhances IGF-IR transcription in prostate cancer cells via a mechanism that involves AR binding to the IGF-IR promoter. AR mutations alter the ability of the mutated protein to regulate IGF-IR expression. Our results suggest that prostate cancer progression is associated with a decrease in IGF-IR expression that could be the result of impaired ability of AR to stimulate IGF-IR gene expression. 2010 Elsevier Ireland Ltd. All rights reserved.
Schayek, Hagit; Seti, Hila; Greenberg, Norman M.; Sun, Shihua; Werner, Haim; Plymate, Stephen R.
2010-01-01
The progression of prostate cancer from an organ-confined, androgen-sensitive disease to a metastatic one is associated with dysregulation of androgen receptor (AR)-regulated target genes and with a decrease in insulin-like growth factor-I receptor (IGF-IR) expression. To investigate the differential effects of wild type (wt) and mutant AR on IGF-IR levels we employed a series of isogenic prostate-derived cell lines and human xenografts. We show that basal and phosphorylated IGF-IR levels progressively decreased as prostate cancer cells became more tumorigenic and metastatic. In addition, we show that wt, but not mutant, AR along with dihydrotestosterone treatment increased IGF-IR promoter activity and endogenous IGF-IR levels. ChIP analysis show enhanced AR binding to the IGF-IR promoter in AR-overexpressing cells. Finally, wt AR-overexpressing cells display an enhanced proliferation rate. In summary, we provide evidence that activated wt AR enhances IGF-IR transcription in prostate cancer cells via a mechanism that involves AR binding to the IGF-IR promoter. AR mutations alter the ability of the mutated protein to regulate IGF-IR expression. Our results suggest that prostate cancer progression is associated with a decrease in IGF-IR expression that could be the result of impaired ability of AR to stimulate IGF-IR gene expression. PMID:20417685
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Zheng; Jin, Bo; Jin, Yaqiong
Androgens (AR) play an important role in initiation and progression of prostate cancer. It has been shown that AR exert their effects mainly through the androgen-activated AR which binds to androgen response elements (AREs) in the regulatory regions of target genes to regulate the transcription of androgen-responsive genes, thus, identification of AR downstream target gene is critical to understand androgen function in prostate cancer. In this study, our results showed that androgen treatment of LNCaP cells induced PTTG1 expression, which was blocked by the androgen receptor antagonist, Casodex. Bioinformatics analysis and experiments using PTTG1 promoter deletion mutants showed that themore » PTTG1 promoter contains a putative androgen response element (ARE), which localizes in the −851 to −836 region of the promoter. Androgen activated androgen receptor (AR) binding to this ARE was confirmed by Chromatin immunoprecipitation (ChIP) assay. Furthermore, Knockdown of PTTG1 expression using short hairpin RNA significantly reduced androgen-induced LNCaP cell growth and invasion. In addition, we showed PTTG1 is highly expressed in metastasis prostate cancer tissue. These results suggest that PTTG1 is a novel downstream target gene of androgen receptor and take part in prostate cancer proliferation and metastasis. - Highlights: • Androgen treatment of LNCaP cells induced PTTG1 expression. • Knockdown of PTTG1 expression significantly reduced androgen-induced LNCaP cell growth and invasion. • PTTG1 is highly expressed in metastasis prostate cancer tissue. • PTTG1 is a novel downstream target gene of androgen receptor.« less
De Oliveira, D H A; Fighera, T M; Bianchet, L C; Kulak, C A M; Kulak, J
2012-12-01
Testosterone is the major gonadal sex steroid produced by the testes in men. Androgens induce male sexual differentiation before birth and sexual maturation during puberty; in adult men, they maintain the function of the male genital system, including spermatogenesis. Testosterone is also produced in smaller amounts by the ovaries in women. The adrenal glands produce the weaker androgens dehydroepiandrosterone, dehydroepiandrosterone sulfate, and androstenedione. Because testosterone can be metabolized to estradiol by the aromatase enzyme, there has been controversy as to which gonadal sex steroid has the greater skeletal effect. In this respect, there is increasing evidence that at least part of the effects of androgens in men can be explained by their aromatization into estrogens. The current evidence suggests that estradiol plays a greater role in maintenance of skeletal health than testosterone, but that androgens also have direct beneficial effects on bone.
Androgen dynamics in vitro in the human prostate gland. Effect of oestradiol-17β
Giorgi, Eleonora P.; Stewart, Joan C.; Grant, J. K.; Shirley, I. M.
1972-01-01
Normal, hyperplastic and adenocarcinomatous human prostatic tissue was perfused in vitro with radioactively labelled androstenedione, testosterone and 5α-dihydrotestosterone with and without added oestradiol-17β. Various parameters of tissue–steroid relationship were measured at the steady state. When oestradiol (0.11 or 0.22μmol/l) was added to the perfusing medium, the entry of the steroids into the tissue and their metabolism was increased in the majority of the glands studied. The `uptake' of all the steroids varied, in response to the addition of oestradiol, in both normal and adenocarcinomatous glands in a way differing from the response of hyperplastic glands. As a consequence, the tissue clearance of the steroids, particularly of androstenedione and testosterone, increased in normal and adenocarcinomatous glands in the presence of oestradiol, and decreased in the hyperplastic tissues. At a concentration 0.33μmol/l, oestradiol decreased the entry of the steroids in all the tissues studied, while the clearance of steroids tended to decrease. The significance of these findings in terms of the regulation of androgen dynamics in vivo in the normal and diseased human prostate, with particular regard to the response to oestrogen treatment, is discussed. PMID:5075225
Estradiol causes the rapid accumulation of cAMP in human prostate.
Nakhla, A M; Khan, M S; Romas, N P; Rosner, W
1994-01-01
Androgens are widely acknowledged to be central to the pathogenesis of benign prostatic hypertrophy (BPH). However, BPH increases in prevalence as men age, at precisely the stage of life when plasma androgens are decreasing. The decrease in total plasma androgens is amplified by an age-related increase in plasma sex hormone-binding globulin (SHBG) that results in a relatively greater decrease in free androgens than in total androgens. In addition, estrogens have long been suspected to be important in BPH, but a direct effect on the human prostate has never been demonstrated. We present data that are consistent with a role for estradiol, and for a decrease in androgens and an increase in SHBG, in the pathogenesis of BPH. We show that estradiol, but not dihydrotestosterone, acts in concert with SHBG to produce an 8-fold increase in intracellular cAMP in human BPH tissue. This increase is not blocked by an antiestrogen and is not provoked by an estrogen (diethylstilbestrol) that does not bind to SHBG, thus excluding the classic estrogen receptor as being operative in these events. Conversely, dihydrotestosterone, which blocks the binding of estradiol to SHBG, completely negates the effect of estradiol. Finally, we demonstrate that the SHBG-steroid-responsive second-messenger system is primarily localized to the prostatic stromal cells and not to the prostatic epithelial cells. Thus, we have shown a cell-specific, powerful, nontranscriptional effect of estradiol on the human prostate. PMID:7515502
A mouse model of androgenetic alopecia.
Crabtree, Judy S; Kilbourne, Edward J; Peano, Bryan J; Chippari, Susan; Kenney, Thomas; McNally, Christopher; Wang, Wei; Harris, Heather A; Winneker, Richard C; Nagpal, Sunil; Thompson, Catherine C
2010-05-01
Androgenetic alopecia (AGA), commonly known as male pattern baldness, is a form of hair loss that occurs in both males and females. Although the exact cause of AGA is not known, it is associated with genetic predisposition through traits related to androgen synthesis/metabolism and androgen signaling mediated by the androgen receptor (AR). Current therapies for AGA show limited efficacy and are often associated with undesirable side effects. A major hurdle to developing new therapies for AGA is the lack of small animal models to support drug discovery research. Here, we report the first rodent model of AGA. Previous work demonstrating that the interaction between androgen-bound AR and beta-catenin can inhibit Wnt signaling led us to test the hypothesis that expression of AR in hair follicle cells could interfere with hair growth in an androgen-dependent manner. Transgenic mice overexpressing human AR in the skin under control of the keratin 5 promoter were generated. Keratin 5-human AR transgenic mice exposed to high levels of 5alpha-dihydrotestosterone showed delayed hair regeneration, mimicking the AGA scalp. This effect is AR mediated, because treatment with the AR antagonist hydroxyflutamide inhibited the effect of dihydrotestosterone on hair growth. These results support the hypothesis that androgen-mediated hair loss is AR dependent and suggest that AR and beta-catenin mediate this effect. These mice can now be used to test new therapeutic agents for the treatment of AGA, accelerating the drug discovery process.
Metabolic Syndrome, Androgens, and Hypertension
Moulana, Mohadetheh; Lima, Roberta; Reckelhoff, Jane F.
2013-01-01
Obesity is one of the constellation of factors that make up the definition of the metabolic syndrome. Metabolic syndrome is also associated with insulin resistance, dyslipidemia, hypertriglyceridemia, and type 2 diabetes mellitus. The presence of obesity and metabolic syndrome in men and women is also associated with increased risk of cardiovascular disease and hypertension. In men, obesity and metabolic syndrome are associated with reductions in testosterone levels. In women, obesity and metabolic syndrome is associated with increases in androgen levels. In men reductions in androgen levels is associated with inflammation. Androgen supplements reduce inflammation in men. In women, increases in androgens are associated with increases in inflammatory cytokines, and reducing androgens reduces inflammation. In this review the possibility that androgens may have different effects on metabolic syndrome and its sequelae in males and females will be discussed. PMID:21274756
Androgen-mediated sex bias impairs efficiency of leukotriene biosynthesis inhibitors in males
Pace, Simona; Pergola, Carlo; Dehm, Friederike; Rossi, Antonietta; Gerstmeier, Jana; Troisi, Fabiana; Pein, Helmut; Schaible, Anja M.; Weinigel, Christina; Rummler, Silke; Northoff, Hinnak; Laufer, Stefan; Maier, Thorsten J.; Rådmark, Olof; Samuelsson, Bengt; Sautebin, Lidia
2017-01-01
Proinflammatory leukotrienes (LTs) are produced by 5-lipoxygenase (5-LO) aided by 5-LO–activating protein (FLAP). LT biosynthesis inhibitors are currently under clinical investigation as treatments for respiratory and cardiovascular diseases. Here, we have revealed a sex bias in the efficiency of clinically relevant LT biosynthesis inhibitors, showing that their effects are superior in females. We found that androgens cause these sex differences by impeding the LT-biosynthetic 5-LO/FLAP complex assembly. Lower doses of the FLAP inhibitor MK886 were required to reduce LTB4 levels in exudates of female versus male mice and rats. Following platelet-activating factor–induced shock, MK886 increased survival exclusively in female mice, and this effect was abolished by testosterone administration. FLAP inhibitors and the novel-type 5-LO inhibitors licofelone and sulindac sulfide exhibited higher potencies in human blood from females, and bioactive 5-LO/FLAP complexes were formed in female, but not male, human and murine leukocytes. Supplementation of female blood or leukocytes with 5α-dihydrotestosterone abolished the observed sex differences. Our data suggest that females may benefit from anti-LT therapy to a greater extent than males, prompting consideration of sex issues in LT modifier development. PMID:28737505
Lillie, Elizabeth O; Bernstein, Leslie; Ursin, Giske
2003-01-01
Testosterone binds to the androgen receptor in target tissue to mediate its effects. Variations in testosterone levels and androgen receptor activity may play a role in the etiology of breast cancer. Here, we review the epidemiologic evidence linking endogenous testosterone to breast cancer risk. Paradoxically, results from observational studies that have examined polymorphisms in the androgen receptor suggest that the low-activity androgen receptor increases breast cancer risk. We review the quality of this evidence and conclude with a discussion of how the androgen receptor and testosterone results coincide. PMID:12793900
Androgens and polycystic ovary syndrome.
Nisenblat, Vicki; Norman, Robert J
2009-06-01
Polycystic ovary syndrome (PCOS) is a common complex endocrine genetic disorder, which involves overproduction of androgens, leading to heterogeneous range of symptoms and associated with increased metabolic and cardiovascular morbidity. This review focuses on androgen biosynthesis, use, metabolism in PCOS and clinical consequences of hyperandrogenism. Controversial definition of the disorder and different phenotypic subgroups present a challenge for clinical and basic research. Further investigation of different phenotypes highlights the fact that PCOS probably represents a group of disorders with different etiologies. Prenatal androgen exposure and adolescent studies suggest early in life androgen excess as initiating factor of PCOS, but insufficient evidence available to confirm this hypothesis. Various intracellular signaling pathways implicated in PCOS steroidogenesis and in androgen action have been studied, however, PCOS pathogenesis remains obscure. Growing evidence links androgens with pathophysiology of PCOS and metabolic derangements. Despite intensive investigation, etiology and underlying mechanisms of PCOS remain unclear, warranting further investigation. Better understanding of molecular and genetic basis might lead to invention of novel therapeutic approaches. Long-term interventional studies that lower androgen levels in women with hyperandrogenism might protect against metabolic and cardiovascular comorbidities are needed.
Corbould, A
2008-10-01
Hyperinsulinemia as a consequence of insulin resistance causes hyperandrogenemia in women. The objective was to review evidence for the converse situation, i.e. whether androgens adversely influence insulin action. Androgen excess could potentially contribute to the pathogenesis of insulin resistance in women with polycystic ovary syndrome (PCOS), metabolic syndrome/type 2 diabetes, and in obese peripubertal girls. An Entrez-PubMed search was conducted to identify studies addressing the relationship of androgens with metabolic syndrome/type 2 diabetes in women. Studies reporting outcomes of androgen administration, interventions to reduce androgen effects in hyperandrogenemic women, and basic studies investigating androgen effects on insulin target tissues were reviewed. Multiple studies showed associations between serum testosterone and insulin resistance or metabolic syndrome/type 2 diabetes risk in women, but their cross-sectional nature did not allow conclusions about causality. Androgen administration to healthy women was associated with development of insulin resistance. Intervention studies in women with hyperandrogenism were limited by small subject numbers and use of indirect methods for assessing insulin sensitivity. However, in three of the seven studies using euglycemic hyperinsulinemic clamps, reduction of androgen levels or blockade of androgen action improved insulin sensitivity. Testosterone administration to female rats caused skeletal muscle insulin resistance. Testosterone induced insulin resistance in adipocytes of women in vitro. In conclusion, the metabolic consequences of androgen excess in women have been under-researched. Studies of long-term interventions that lower androgen levels or block androgen effects in young women with hyperandrogenism are needed to determine whether these might protect against metabolic syndrome/type 2 diabetes in later life. Copyright (c) 2008 John Wiley & Sons, Ltd.
Tamae, Daniel; Mostaghel, Elahe; Montgomery, Bruce; Nelson, Peter S; Balk, Steven P; Kantoff, Philip W; Taplin, Mary-Ellen; Penning, Trevor M
2015-06-05
Prostate cancer is the second leading cause of cancer death in the United States. Treatment of localized high-risk disease and de novo metastatic disease frequently leads to relapse. These metastatic castration resistant prostate cancers (mCRPC) claim a high mortality rate, despite the extended survival afforded by the growing armamentarium of androgen deprivation, radiation and immunotherapies. Here, we review two studies of neoadjuvant treatment of high-risk localized prostate cancer prior to prostatectomy, the total androgen pathway suppression (TAPS) trial and the neoadjuvant abiraterone acetate (AA) trial. These two trials assessed the efficacy of the non-specific P450c17 inhibitor, ketoconazole and the specific P450c17 inhibitor, AA, to inhibit tissue and serum androgen levels. Furthermore, a novel and validated stable isotope dilution liquid chromatography electrospray ionization selected reaction monitoring mass spectrometry assay was used to accurately quantify adrenal and gonadal androgens in circulation during the course of these trials. The adrenal androgens, Δ(4)-androstene-3,17-dione, dehydroepiandrosterone and dehydroepiandrosterone sulfate were significantly reduced in the patients receiving ketoconazole or AA compared to those who did not. However, in both trials, a significant amount of DHEA-S (∼20 μg/dL) persists and thus may serve as a depot for intratumoral conversion to the potent androgen receptor ligands, testosterone (T) and 5α-dihydrotestosterone (DHT). The final step in conversion of Δ(4)-androstene-3,17-dione and 5α-androstanedione to T and DHT, respectively, is catalyzed by AKR1C3. We therefore present the case that in the context of the DHEA-S depot, P450c17 and AKR1C3 inhibition may be an effective combinatorial treatment strategy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Androgen Receptor Signaling in Bladder Cancer
Li, Peng; Chen, Jinbo; Miyamoto, Hiroshi
2017-01-01
Emerging preclinical findings have indicated that steroid hormone receptor signaling plays an important role in bladder cancer outgrowth. In particular, androgen-mediated androgen receptor signals have been shown to correlate with the promotion of tumor development and progression, which may clearly explain some sex-specific differences in bladder cancer. This review summarizes and discusses the available data, suggesting the involvement of androgens and/or the androgen receptor pathways in urothelial carcinogenesis as well as tumor growth. While the precise mechanisms of the functions of the androgen receptor in urothelial cells remain far from being fully understood, current evidence may offer chemopreventive or therapeutic options, using androgen deprivation therapy, in patients with bladder cancer. PMID:28241422
Mitsiades, Nicholas; Sung, Clifford C.; Schultz, Nikolaus; Danila, Daniel C.; He, Bin; Eedunuri, Vijay Kumar; Fleisher, Martin; Sander, Chris; Sawyers, Charles L.; Scher, Howard I.
2012-01-01
Androgen receptor (AR) signaling persists in castration-resistant prostate carcinomas (CRPCs), due to several mechanisms that include increased AR expression and intratumoral androgen metabolism. We investigated the mechanisms underlying aberrant expression of transcripts involved in androgen metabolism in CRPC. We compared gene expression profiles and DNA copy number alteration (CNA) data from 29 normal prostate tissue samples, 127 primary prostate carcinomas (PCas) and 19 metastatic PCas. Steroidogenic enzyme transcripts were evaluated by qRT-PCR in PCa cell lines and circulating tumor cells (CTCs) from CRPC patients. Metastatic PCas expressed higher transcript levels for AR and several steroidogenic enzymes, including SRD5A1, SRD5A3, and AKR1C3, while expression of SRD5A2, CYP3A4, CYP3A5 and CYP3A7 was decreased. This aberrant expression was rarely associated with CNAs. Instead, our data suggest distinct patterns of coordinated aberrant enzyme expression. Inhibition of AR activity by itself stimulated AKR1C3 expression. The aberrant expression of the steroidogenic enzyme transcripts were detected in CTCs from CRPC patients. In conclusion, our findings identify substantial interpatient heterogeneity and distinct patterns of dysregulated expression of enzymes involved in intratumoral androgen metabolism in PCa. These steroidogenic enzymes represent targets for complete suppression of systemic and intratumoral androgen levels, an objective that is supported by the clinical efficacy of the CYP17 inhibitor abiraterone. A comprehensive AR axis targeting approach via simultaneous, frontline enzymatic blockade and/or transcriptional repression of several steroidogenic enzymes, in combination with GnRH analogs and potent anti-androgens, would represent a powerful future strategy for PCa management. PMID:22971343
Allan, George; Sbriscia, Tifanie; Linton, Olivia; Lai, Muh-Tsann; Haynes-Johnson, Donna; Bhattacharjee, Sheela; Ng, Raymond; Sui, Zhihua; Lundeen, Scott
2008-06-01
Androgens are required for the maintenance of normal sexual activity in adulthood and for enhancing muscle growth and lean body mass in adolescents and adults. Androgen receptor (AR) ligands with tissue selectivity (selective androgen receptor modulators, or SARMs) have potential for treating muscle wasting, hypogonadism of aging, osteoporosis, female sexual dysfunction, and other indications. JNJ-37654032 is a nonsteroidal AR ligand with mixed agonist and antagonist activity in androgen-responsive cell-based assays. It is an orally active SARM with muscle selectivity in orchidectomized rat models. It stimulated growth of the levator ani muscle with ED(50) 0.8 mg/kg, stimulating maximal growth at a dose of 3mg/kg. In contrast, it stimulated ventral prostate growth to 21% of its full size at 3mg/kg. At the same time, JNJ-37654032 reduced prostate weight in intact rats by 47% at 3mg/kg, while having no inhibitory effect on muscle. Using magnetic resonance imaging to monitor body composition, JNJ-37654032 restored about 20% of the lean body mass lost following orchidectomy in aged rats. JNJ-37654032 reduced follicle-stimulating hormone levels in orchidectomized rats and reduced testis size in intact rats. JNJ-37654032 is a potent prostate-sparing SARM with the potential for clinical benefit in muscle-wasting diseases.
Vaz, Cátia V; Maia, Cláudio J; Marques, Ricardo; Gomes, Inês M; Correia, Sara; Alves, Marco G; Cavaco, José E; Oliveira, Pedro F; Socorro, Sílvia
2014-09-01
Regucalcin (RGN) is a calcium (Ca(2+) )-binding protein underexpressed in prostate adenocarcinoma comparatively to non-neoplastic prostate or benign prostate hyperplasia cases. Moreover, RGN expression is negatively associated with the cellular differentiation of prostate adenocarcinoma, suggesting that loss of RGN may be associated with tumor onset and progression. However, the RGN actions over the control of prostate cell growth have not been investigated. Androgens are implicated in the promotion of prostate cell proliferation, thus we studied the in vivo effect of androgens on RGN expression in rat prostate. The role of RGN modulating cell proliferation and apoptotic pathways in rat prostate was investigated using transgenic animals (Tg-RGN) overexpressing the protein. In vivo stimulation with 5α-dihydrotestosterone (DHT) down-regulated RGN expression in rat prostate. Cell proliferation index and prostate weight were reduced in Tg-RGN, which was concomitant with altered expression of cell-cycle regulators. Tg-RGN presented diminished expression of the oncogene H-ras and increased expression of cell-cycle inhibitor p21. Levels of anti-apoptotic Bcl-2, as well as the Bcl-2/Bax protein ratio were increased in prostates overexpressing RGN. Both caspase-3 expression and enzyme activity were decreased in the prostates of Tg-RGN. Overexpression of RGN resulted in inhibition of cell proliferation and apoptotic pathways, which demonstrated its role maintaining prostate growth balance. Thus, deregulation of RGN expression may be an important event favoring the development of prostate cancer. Moreover, the DHT effect down-regulating RGN expression in rat prostate highlighted for the importance of this protein in prostatic physiology. © 2014 Wiley Periodicals, Inc.
Hong, Mee Young; Seeram, Navindra P.; Heber, David
2008-01-01
Prostate cancer is dependent on circulating testosterone in its early stages and is treatable with radiation and surgery. However, recurrent prostate tumors advance to an androgen-independent state where they progress in the absence of circulating testosterone leading to metastasis and death. During the development of androgen independence, prostate cancer cells are known to increase intracellular testosterone synthesis which maintains cancer cell growth in the absence of significant amounts of circulating testosterone. Overexpression of the androgen receptor (AR) occurs in androgen-independent prostate cancer and has been proposed as another mechanism promoting the development of androgen independence. The LNCaP-AR cell line is engineered to overexpress AR but is otherwise similar to the widely studied LNCaP cell line. We have previously shown that pomegranate extracts inhibit both androgen-dependent and androgen-independent prostate cancer cell growth. In the present study, we examined the effects of pomegranate polyphenols, ellagitannin-rich extract and whole juice extract on the expression of genes for key androgen synthesizing enzymes and the AR. We measured expression of the HSD3B2, AKR1C3 and SRD5A1 genes for the respective androgen synthesizing enzymes in LNCaP, LNCaP-AR, and DU-145 human prostate cancer cells. A two-fold suppression of gene expression was considered statistically significant. Pomegranate polyphenols inhibited gene expression and AR most consistently in the LNCaP-AR cell line (P =.05). Therefore, inhibition by pomegranate polyphenols of gene expression involved in androgen synthesis enzymes and the AR may be of particular importance in androgen-independent prostate cancer cells and the subset of human prostate cancers where AR is upregulated. PMID:18479901
Mitchell, Lorna H; Johnson, Theodore R; Lu, Guang Wei; Du, Daniel; Datta, Kaushik; Grzemski, Felicity; Shanmugasundaram, Veerabahu; Spence, Julie; Wade, Kim; Wang, Zhi; Sun, Kevin; Lin, Kristin; Hu, Lain-Yen; Sexton, Karen; Raheja, Neil; Kostlan, Catherine; Pocalyko, David
2010-06-10
A novel nonsteroidal androgen receptor antagonist, (R)-4-(1-benzyl-4,4-dimethyl-2-oxopyrrolidin-3-yloxy)-2-(trifluoromethyl)benzonitrile (1), for the topical control of sebum production is reported. This compound, which is potent, selective, and efficacious in the clinically validated golden Syrian hamster ear animal model, was designed to be delivered to the pilosebaceous unit, the site of action, preferentially by the follicular route.
Fernández-Cancio, Mónica; Rodó, Joan; Andaluz, Pilar; Martínez de Osaba, María Jesús; Rodríguez-Hierro, Francisco; Esteban, Cristina; Carrascosa, Antonio; Audí, Laura
2004-01-01
A patient with male pseudohermaphroditism and clinical diagnosis of partial androgen insensitivity in the neonatal period was studied at pubertal age for a molecular diagnosis. Hormone studies were conducted at baseline and under hCG stimulation for testosterone and dihydrotestosterone determinations at 2 months of age. Gonadectomy was performed at 4 months. At the age of 13 years genital skin fibroblasts were studied for androgen binding and 5alpha-reductase activity and peripheral blood DNA was available for androgen receptor (AR) and 5alpha-reductase (SRD5A2) gene analysis. Exons 1-8 of AR gene and exons 1-5 of SRD5A2 gene were sequenced. AR gene coding sequences were normal. SRD5A2 gene analysis revealed two heterozygote mutations (G115D and R246W), with the mother carrying the G115D and the father the R246W mutations. The compound heterozygote mutations in SRD5A2 gene explained an extremely low 5alpha-reductase enzyme activity in genital skin fibroblasts. Revision of hormonal data from the neonatal period revealed an increased testosterone-to-dihydrotestosterone ratio at the end of an hCG stimulation test, which concurred with the molecular diagnosis. Testis morphology at 4 months of age was normal. Clinical and biochemical differential diagnosis between partial androgen insensitivity syndrome and 5alpha-reductase enzyme deficiency is difficult in the neonatal period and before puberty. Our results show that in our patient the testosterone-to-dihydrotestosterone ratio would have adequately orientated the diagnosis. The two mutations in SRD5A2 gene have been described in patients of different lineages, though not in combination to date. Testis morphology showed that, during early infancy, the 5alpha-reductase deficiency may not have affected interstitial or tubular development. Copyright (c) 2004 S. Karger AG, Basel.
Polycystic ovarian disease: the adrenal connection.
Marouliss, George B; Triantafillidis, Ioannis K
2006-01-01
Polycystic ovarian disease (PCOD) is characterized by hyperandrogenemia, ovulatory dysfunction and polycystic ovaries (PCO). The increased androgen production in PCOD comes primarily from the ovaries. However, in about 40% of patients there is excessive adrenal androgen production (DHEA, DHEA-Sulfate, Androstenedione, Testosterone and Dihydrotestosterone). The contribution of the adrenal in the PCOD is suggested by the presence of adrenal androgen excess in PCO, the presence of PCO in women with enzymatic adrenal hyperplasia as well as in women with adrenal tumors. However, the cause of adrenal androgen hypersecretion is not yet fully understood but it may include endogenous hypersecretion of the zona reticularis of unclear cause, hypersecretion of cortical-androgen-stimulating hormone (CASH), stress, hyperprolactinemia, adrenal enzymatic defects etc. This short review covers the aspects of adrenal androgen hypersecretion in PCOD.
Lévesque, Éric; Laverdière, Isabelle; Lacombe, Louis; Caron, Patrick; Rouleau, Mélanie; Turcotte, Véronique; Têtu, Bernard; Fradet, Yves; Guillemette, Chantal
2014-02-01
Polymorphisms in the genes SRD5A1 and SRD5A2 encoding androgen biosynthetic 5α-reductase enzymes have been associated with an altered risk of biochemical recurrence after radical prostatectomy in localized prostate cancer. To gain potential insights into SRD5A biologic effects, we examined the relationship between SRD5A prognostic markers and endogenous sex-steroid levels measured by mass spectrometry in plasma samples and corresponding prostatic tissues of patients with prostate cancer. We report that five of the seven SRD5A markers differentially affect sex-steroid profiles of dihydrotestosterone and its metabolites in both the circulation and prostatic tissues of patients with prostate cancer. Remarkably, a 32% increase in intraprostatic testosterone levels was observed in the presence of the high-risk SRD5A rs2208532 polymorphism. Moreover, SRD5A2 markers were associated predominantly with circulating levels of inactive glucuronides. Indeed, the rs12470143 SRD5A2 protective allele was associated with high circulating androstane-3α, 17β-diol-17-glucuronide (3α-diol-17G) levels as opposed to lower levels of both 3α-diol-17G and androsterone-glucuronide observed with the rs2208532 SRD5A2 risk allele. Moreover, SRD5A2 rs676033 and rs523349 (V89L) risk variants, in strong linkage disequilibrium, were associated with higher circulating levels of 3α-diol-3G. The SRD5A2 rs676033 variant further correlated with enhanced intraprostatic exposure to 5α-reduced steroids (dihydrotestosterone and its metabolite 3β-diol). Similarly, the SRD5A1 rs166050C risk variant was associated with greater prostatic exposure to androsterone, whereas no association was noted with circulating steroids. Our data support the association of 5α-reductase germline polymorphisms with the hormonal milieu in patients with prostate cancer. Further studies are needed to evaluate if these variants influence 5α-reductase inhibitor efficacy. ©2013 AACR.
Givens, Melissa L; Deuster, Patricia
2015-01-01
Androgen use outside of legitimate medical therapy is a perceived concern that is drawing attention across military and specifically Special Operations Forces (SOF) communities. For leadership and the medical community to properly address the issue and relate to those individuals who are using or considering use, it will be crucial to understand the scope of the problem. Limited data suggest that the prevalence of androgen use may be increasing, and inferences made from the scientific literature suggest that SOF may be a population of concern. While risks of androgen use are well known, there are little data specific to military performance that can be applied to a rigorous risk:benefit analysis, allowing myths and poorly supported theories to perpetuate within the community. Further efforts to define the potential benefits balanced against the short- and long-term risks should be undertaken. Providers within the SOF community should arm themselves with information to engage androgen users and leadership in meaningful discussion regarding androgen use. 2015.
Blok, L J; Chang, G T G; Steenbeek-Slotboom, M; Weerden, W M van; Swarts, H G P; Pont, J J H H M De; Steenbrugge, G J van; Brinkmann, A O
1999-01-01
The β1-subunit of Na+,K+-ATPase was isolated and identified as an androgen down-regulated gene. Expression was observed at high levels in androgen-independent as compared to androgen-dependent (responsive) human prostate cancer cell lines and xenografts when grown in the presence of androgens. Down-regulation of the β1-subunit was initiated at concentrations between 0.01 nM and 0.03 nM of the synthetic androgen R1881 after relatively long incubation times (> 24 h). Using polyclonal antibodies, the concentration of β1-subunit protein, but not of the α1-subunit protein, was markedly reduced in androgen-dependent human prostate cancer cells (LNCaP-FGC) cultured in the presence of androgens. In line with these observations it was found that the protein expression of total Na+,K+-ATPase in the membrane (measured by 3H-ouabain binding) was also markedly decreased. The main function of Na+,K+-ATPase is to maintain sodium and potassium homeostasis in animal cells. The resulting electrochemical gradient is facilitative for transport of several compounds over the cell membrane (for example cisplatin, a chemotherapeutic agent experimentally used in the treatment of hormone-refractory prostate cancer). Here we observed that a ouabain-induced decrease of Na+,K+-ATPase activity in LNCaP-FGC cells results in reduced sensitivity of these cells to cisplatin-treatment. Surprisingly, androgen-induced decrease of Na+,K+-ATPase expression, did not result in significant protection against the chemotherapeutic agent. © 1999 Cancer Research Campaign PMID:10487609
A MATHEMATICAL MODEL FOR THE KINETICS OF THE MALE REPRODUCTIVE ENDOCRINE SYSTEM
In this presentation a model for the hormonal regulation of the reproductive endocrine system in the adult male rat will be discussed. The model includes a description of the kinetics of the androgenic hormones testosterone and dihydrotestosterone, as well as the receptor-mediate...
Hamdi, M M; Mutungi, G
2010-02-01
It is generally believed that steroid hormones have both genomic and non-genomic (rapid) actions. Although the latter form an important component of the physiological response of these hormones, little is known about the cellular signalling pathway(s) mediating these effects and their physiological functions in adult mammalian skeletal muscle fibres. Therefore, the primary aim of this study was to investigate the non-genomic actions of dihydrotestosterone (DHT) and their physiological role in isolated intact mammalian skeletal muscle fibre bundles. Our results show that treating the fibre bundles with physiological concentrations of DHT increases both twitch and tetanic contractions in fast twitch fibres. However, it decreases them in slow twitch fibres. These changes in force are accompanied by an increase in the phosphorylation of MAPK/ERK1/2 in both fibre types and that of regulatory myosin light chains in fast twitch fibres. Both effects were insensitive to inhibitors of Src kinase, androgen receptor, insulin-like growth factor 1 receptor and platelet-derived growth factor receptor. However, they were abolished by the MAPK/ERK1/2 kinase inhibitor PD98059 and the epidermal growth factor (EGF) receptor inhibitor tyrphostin AG 1478. In contrast, testosterone had no effect on force and increased the phosphorylation of ERK1/2 in slow twitch fibres only. From these results we conclude that sex steroids have non-genomic actions in isolated intact mammalian skeletal muscle fibres. These are mediated through the EGF receptor and one of their main physiological functions is the enhancement of force production in fast twitch skeletal muscle fibres.
Abedinpour, Parisa; Baron, Véronique T; Chrastina, Adrian; Rondeau, Gaelle; Pelayo, Jennifer; Welsh, John; Borgström, Per
2017-12-01
Plumbagin is a candidate drug for the treatment of prostate cancer. Previous observations indicated that it may improve the efficacy of androgen deprivation therapy (ADT). This study evaluates the effectiveness of treatment with combinations of plumbagin and alternative strategies for ADT in mouse models of prostate cancer to support its clinical use. Plumbagin was administered per oral in a new sesame oil formulation. Standard toxicology studies were performed in rats. For tumor growth studies, mouse prostate cancer cell spheroids were placed on top of grafted prostate tissue in a dorsal chamber and allowed to form tumors. Mice were separated in various treatment groups and tumor size was measured over time by intra-vital microscopy. Survival studies were done in mice after injection of prostate cancer cells in the prostate of male animals. Androgen receptor (AR) levels were analyzed by Western blot from prostate cancer cells treated with plumbagin. Plumbagin caused a decrease in AR levels in vitro. In mice, plumbagin at 1 mg/kg in sesame oil displayed low toxicity and caused a 50% tumor regression when combined with castration. The combination of plumbagin with various forms of chemical ADT including treatment with a GnRH receptor agonist, a GnRH receptor antagonist, or CYP17A1 inhibitors, outperformed ADT alone, increasing mouse survival compared to the standard regimen of castration alone. In contrast, the combination of plumbagin with AR antagonists, such as bicalutamide and enzalutamide, showed no improvement over AR antagonists alone. Thus, plumbagin is effective in combination with drugs that prevent the synthesis of testosterone or its conversion to dihydrotestosterone, but not with drugs that bind to AR. Plumbagin significantly improves the effect of ADT drugs currently used in the clinic, with few side effects in mice. © 2017 Wiley Periodicals, Inc.
Arai, Kiyoshi; Homma, Tsuyoshi; Morikawa, Yuka; Ubukata, Naoko; Tsuruoka, Hiyoyuki; Aoki, Kazumasa; Ishikawa, Hirokazu; Mizuno, Makoto; Sada, Toshio
2015-08-15
The present study was designed to characterize the pharmacological profile of CS-3150, a novel non-steroidal mineralocorticoid receptor antagonist. In the radioligand-binding assay, CS-3150 inhibited (3)H-aldosterone binding to mineralocorticoid receptor with an IC50 value of 9.4nM, and its potency was superior to that of spironolactone and eplerenone, whose IC50s were 36 and 713nM, respectively. CS-3150 also showed at least 1000-fold higher selectivity for mineralocorticoid receptor over other steroid hormone receptors, glucocorticoid receptor, androgen receptor and progesterone receptor. In the reporter gene assay, CS-3150 inhibited aldosterone-induced transcriptional activation of human mineralocorticoid receptor with an IC50 value of 3.7nM, and its potency was superior to that of spironolactone and eplerenone, whose IC50s were 66 and 970nM, respectively. CS-3150 had no agonistic effect on mineralocorticoid receptor and did not show any antagonistic or agonistic effect on glucocorticoid receptor, androgen receptor and progesterone receptor even at the high concentration of 5μM. In adrenalectomized rats, single oral administration of CS-3150 suppressed aldosterone-induced decrease in urinary Na(+)/K(+) ratio, an index of in vivo mineralocorticoid receptor activation, and this suppressive effect was more potent and longer-lasting than that of spironolactone and eplerenone. Chronic treatment with CS-3150 inhibited blood pressure elevation induced by deoxycorticosterone acetate (DOCA)/salt-loading to rats, and this antihypertensive effect was more potent than that of spironolactone and eplerenone. These findings indicate that CS-3150 is a selective and highly potent mineralocorticoid receptor antagonist with long-lasting oral activity. This agent could be useful for the treatment of hypertension, cardiovascular and renal disorders. Copyright © 2015 Elsevier B.V. All rights reserved.
Sathianathen, Niranjan J; Fan, Yunhua; Jarosek, Stephanie L; Lawrentschuk, Nathan L; Konety, Badrinath R
2018-05-03
Preclinical models have demonstrated that androgen receptor modulation can influence bladder carcinogenesis with an inverse association observed between serum androgen levels and bladder cancer (BC) incidence. It is still unclear whether 5α-reductase inhibitors, by preventing the conversion of testosterone to dihydrotestosterone, have a similar effect. This study aims to evaluate whether dihydrotestosterone-mediated androgen activity has an impact on BC incidence in a cohort of men included in a clinical trial of finasteride vs. placebo with rigorous compliance monitoring. A secondary analysis was performed on all patients enrolled in the Medical Therapy for Prostatic Symptoms (MTOPS) Study and included in the biopsy substudy. Men were stratified into groups based on receiving finasteride and the incidence of BC compared between the groups. After exclusions for poor finasteride compliance (n = 338) and missing serum hormone results (n = 9), 2,700 men were eligible for analysis. In total, 0.8% (n = 18) of the cohort was diagnosed with BC during the trial period. There was no difference in the incidence of BC between men who received finasteride and those who did not (0.74% [n = 9] vs. 0.61% [n = 9], P = 0.67). Neither serum testosterone levels, prostate cancer diagnosis nor urinary bother (measured by International Prostate Symptom Score) demonstrated an association with BC diagnosis. These relationships were consistent in the subgroup of men in the biopsy substudy. There was no observable relationship between decreased dihydrotestosterone levels and BC diagnosis. Copyright © 2018 Elsevier Inc. All rights reserved.
2013-01-01
Decreases of the sex steroids, testosterone and estrogen, are associated with increased risk of Alzheimer’s disease. Testosterone and estrogen supplementation improves cognitive deficits in animal models of Alzheimer’s disease. Sex hormones play a role in the regulation of amyloid-β via induction of the amyloid-β degrading enzymes neprilysin and insulin-degrading enzyme. To mimic the effect of dihydrotestosterone (DHT), we administered a selective androgen receptor agonist, ACP-105, alone and in combination with the selective estrogen receptor β (ERβ) agonist AC-186 to male gonadectomized triple transgenic mice. We assessed long-term spatial memory in the Morris water maze, spontaneous locomotion, and anxiety-like behavior in the open field and in the elevated plus maze. We found that ACP-105 given alone decreases anxiety-like behavior. Furthermore, when ACP-105 is administered in combination with AC-186, they increase the amyloid-β degrading enzymes neprilysin and insulin-degrading enzyme and decrease amyloid-β levels in the brain as well as improve cognition. Interestingly, the androgen receptor level in the brain was increased by chronic treatment with the same combination treatment, ACP-105 and AC-186, not seen with DHT or ACP-105 alone. Based on these results, the beneficial effect of the selective ERβ agonist as a potential therapeutic for Alzheimer’s disease warrants further investigation. PMID:24020966
Martínez, Ana; Ramos, Guillermo; Martínez-Torres, Martín; Nicolás, Leticia; Carmona, Agustín; Cárdenas, Mario; Luis, Juana
2015-05-01
Here, we analyzed the effects of testosterone (T) and its metabolites, estradiol (E2) and dihydrotestosterone (DHT), on the onset of paternal behavior in virgin male Mongolian gerbils (Meriones unguiculatus). We hypothesized that T and E2, but not DHT, would facilitate the onset of paternal behavior. Seventy males displaying aggression toward pups were selected through a paternal behavior screening test. Forty males were bilaterally castrated. Of them, 10 were implanted with T, 10 with E2, and 10 with DHT, and 10 received no treatment. Another 30 males underwent a sham procedure. In these gerbils, T, E2 and DHT were measured to obtain the basal levels of these hormones. After treatment, the paternal behavior test was conducted again. Blood samples were obtained immediately after the administration of the test for the quantification of T, E2 and DHT by radioimmunoassay. Surprisingly, 100% of the males that received T, E2 and DHT implants stopped being aggressive and became paternal. Castrated and sham-operated males displayed no changes in their aggressive behaviors. This is the first report that T and its metabolites are involved in neuroendocrine mechanisms that inhibit aggression toward pups and facilitate paternal behavior in virgin male Mongolian gerbils. In addition, this is the first report of regulation of paternal behavior in a rodent by estrogenic and androgenic pathways. Copyright © 2015 Elsevier Inc. All rights reserved.
Jiang, Cheng; Lee, Hyo-Jeong; Li, Guang-xun; Guo, Junming; Malewicz, Barbara; Zhao, Yan; Lee, Eun-Ok; Lee, Hyo-Jung; Lee, Jae-Ho; Kim, Min-Seok; Kim, Sung-Hoon; Lu, Junxuan
2006-01-01
Androgen and androgen receptor (AR)-mediated signaling are crucial for the development of prostate cancer. Identification of novel and naturally occurring phytochemicals that target androgen and AR signaling from Oriental medicinal herbs holds exciting promises for the chemoprevention of this disease. In this article, we report the discovery of strong and long-lasting antiandrogen and AR activities of the ethanol extract of a herbal formula (termed KMKKT) containing Korean Angelica gigas Nakai (AGN) root and nine other Oriental herbs in the androgen-dependent LNCaP human prostate cancer cell model. The functional biomarkers evaluated included a suppression of the expression of prostate-specific antigen (PSA) mRNA and protein (IC50, approximately 7 microg/mL, 48-hour exposure) and an inhibition of androgen-induced cell proliferation through G1 arrest and of the ability of androgen to suppress neuroendocrine differentiation at exposure concentrations that did not cause apoptosis. Through activity-guided fractionation, we identified decursin from AGN as a novel antiandrogen and AR compound with an IC50 of approximately 0.4 microg/mL (1.3 micromol/L, 48-hour exposure) for suppressing PSA expression. Decursin also recapitulated the neuroendocrine differentiation induction and G1 arrest actions of the AGN and KMKKT extracts. Mechanistically, decursin in its neat form or as a component of AGN or KMKKT extracts inhibited androgen-stimulated AR translocation to the nucleus and down-regulated AR protein abundance without affecting the AR mRNA level. The novel antiandrogen and AR activities of decursin and decursin-containing herbal extracts have significant implications for the chemoprevention and treatment of prostate cancer and other androgen-dependent diseases.
Androgens in pregnancy: roles in parturition
Makieva, Sofia; Saunders, Philippa T.K.; Norman, Jane E.
2014-01-01
BACKGROUND Understanding the physiology of pregnancy enables effective management of pregnancy complications that could otherwise be life threatening for both mother and fetus. A functional uterus (i) retains the fetus in utero during pregnancy without initiating stretch-induced contractions and (ii) is able to dilate the cervix and contract the myometrium at term to deliver the fetus. The onset of labour is associated with successful cervical remodelling and contraction of myometrium, arising from concomitant activation of uterine immune and endocrine systems. A large body of evidence suggests that actions of local steroid hormones may drive changes occurring in the uterine microenvironment at term. Although there have been a number of studies considering the potential role(s) played by progesterone and estrogen at the time of parturition, the bio-availability and effects of androgens during pregnancy have received less scrutiny. The aim of this review is to highlight potential roles of androgens in the biology of pregnancy and parturition. METHODS A review of published literature was performed to address (i) androgen concentrations, including biosynthesis and clearance, in maternal and fetal compartments throughout gestation, (ii) associations of androgen concentrations with adverse pregnancy outcomes, (iii) the role of androgens in the physiology of cervical remodelling and finally (iv) the role of androgens in the physiology of myometrial function including any impact on contractility. RESULTS Some, but not all, androgens increase throughout gestation in maternal circulation. The effects of this increase are not fully understood; however, evidence suggests that increased androgens might regulate key processes during pregnancy and parturition. For example, androgens are believed to be critical for cervical remodelling at term, in particular cervical ripening, via regulation of cervical collagen fibril organization. Additionally, a number of studies highlight
Androgens in pregnancy: roles in parturition.
Makieva, Sofia; Saunders, Philippa T K; Norman, Jane E
2014-01-01
Understanding the physiology of pregnancy enables effective management of pregnancy complications that could otherwise be life threatening for both mother and fetus. A functional uterus (i) retains the fetus in utero during pregnancy without initiating stretch-induced contractions and (ii) is able to dilate the cervix and contract the myometrium at term to deliver the fetus. The onset of labour is associated with successful cervical remodelling and contraction of myometrium, arising from concomitant activation of uterine immune and endocrine systems. A large body of evidence suggests that actions of local steroid hormones may drive changes occurring in the uterine microenvironment at term. Although there have been a number of studies considering the potential role(s) played by progesterone and estrogen at the time of parturition, the bio-availability and effects of androgens during pregnancy have received less scrutiny. The aim of this review is to highlight potential roles of androgens in the biology of pregnancy and parturition. A review of published literature was performed to address (i) androgen concentrations, including biosynthesis and clearance, in maternal and fetal compartments throughout gestation, (ii) associations of androgen concentrations with adverse pregnancy outcomes, (iii) the role of androgens in the physiology of cervical remodelling and finally (iv) the role of androgens in the physiology of myometrial function including any impact on contractility. Some, but not all, androgens increase throughout gestation in maternal circulation. The effects of this increase are not fully understood; however, evidence suggests that increased androgens might regulate key processes during pregnancy and parturition. For example, androgens are believed to be critical for cervical remodelling at term, in particular cervical ripening, via regulation of cervical collagen fibril organization. Additionally, a number of studies highlight potential roles for androgens
Mostaghel, Elahe A; Morgan, Andrew; Zhang, Xiaotun; Marck, Brett T; Xia, Jing; Hunter-Merrill, Rachel; Gulati, Roman; Plymate, Stephen; Vessella, Robert L; Corey, Eva; Higano, Celestia S; Matsumoto, Alvin M; Montgomery, R Bruce; Nelson, Peter S
2014-01-01
Factors influencing differential responses of prostate tumors to androgen receptor (AR) axis-directed therapeutics are poorly understood, and predictors of treatment efficacy are needed. We hypothesized that the efficacy of inhibiting DHT ligand synthesis would associate with intra-tumoral androgen ratios indicative of relative dependence on DHT-mediated growth. We characterized two androgen-sensitive prostate cancer xenograft models after androgen suppression by castration in combination with the SRD5A inhibitor, dutasteride, as well as a panel of castration resistant metastases obtained via rapid autopsy. In LuCaP35 tumors (intra-tumoral T:DHT ratio 2:1) dutasteride suppressed DHT to 0.02 ng/gm and prolonged survival vs. castration alone (337 vs.152 days, HR 2.8, p = 0.0015). In LuCaP96 tumors (T:DHT 10:1), survival was not improved despite similar DHT reduction (0.02 ng/gm). LuCaP35 demonstrated higher expression of steroid biosynthetic enzymes maintaining DHT levels (5-fold higher SRD5A1, 41 fold higher, 99-fold higher RL-HSD, p<0.0001 for both), reconstitution of intra-tumoral DHT (to ∼30% of untreated tumors), and ∼2 fold increased expression of full length AR. In contrast, LuCaP96 demonstrated higher levels of steroid catabolizing enzymes (6.9-fold higher AKR1C2, 3000-fold higher UGT2B15, p = 0.002 and p<0.0001 respectively), persistent suppression of intra-tumoral DHT, and 6-8 fold induction of full length AR and the ligand independent V7 AR splice variant. Human metastases demonstrated bio-active androgen levels and AR full length and AR splice-variant expression consistent with the range observed in xenografts. Intrinsic differences in basal steroidogenesis, as well as variable expression of full length and splice-variant AR, associate with response and resistance to pre-receptor AR ligand suppression. Expression of steroidogenic enzymes and AR isoforms may serve as potential biomarkers of sensitivity to potent AR-axis inhibition and should be
Neuroendocrine Consequences of Androgen Excess in Female Rodents
Foecking, Eileen M.; McDevitt, Melissa A.; Acosta-Martínez, Maricedes; Horton, Teresa H.; Levine, Jon E.
2008-01-01
Androgens exert significant organizational and activational effects on the nervous system and behavior. Despite the fact that female mammals generally produce low levels of androgens, relative to the male of the same species, increasing evidence suggests that androgens can exert profound effects on the normal physiology and behavior of females during fetal, neonatal, and adult stages of life. This review examines the effects of exposure to androgens at three stages of development – as an adult, during early postnatal life and as a fetus, on reproductive hormone secretions in female rats. We examine the effects of androgen exposure both as a model of neuroendocrine sexual differentiation and with respect to the role androgens play in the normal female. We then discuss the hypothesis that androgens may cause epigenetic modification of estrogen target genes in the brain. Finally we consider the clinical consequences of excess androgen exposure in women. PMID:18374922
Cellular androgen content influences enzalutamide agonism of F877L mutant androgen receptor
Coleman, Daniel J.; Van Hook, Kathryn; King, Carly J.; Schwartzman, Jacob; Lisac, Robert; Urrutia, Joshua; Sehrawat, Archana; Woodward, Josha; Wang, Nicholas J.; Gulati, Roman; Thomas, George V.; Beer, Tomasz M.; Gleave, Martin; Korkola, James E.; Gao, Lina; Heiser, Laura M.; Alumkal, Joshi J.
2016-01-01
Prostate cancer is the most commonly diagnosed and second-most lethal cancer among men in the United States. The vast majority of prostate cancer deaths are due to castration-resistant prostate cancer (CRPC) – the lethal form of the disease that has progressed despite therapies that interfere with activation of androgen receptor (AR) signaling. One emergent resistance mechanism to medical castration is synthesis of intratumoral androgens that activate the AR. This insight led to the development of the AR antagonist enzalutamide. However, resistance to enzalutamide invariably develops, and disease progression is nearly universal. One mechanism of resistance to enzalutamide is an F877L mutation in the AR ligand-binding domain that can convert enzalutamide to an agonist of AR activity. However, mechanisms that contribute to the agonist switch had not been fully clarified, and there were no therapies to block AR F877L. Using cell line models of castration-resistant prostate cancer (CRPC), we determined that cellular androgen content influences enzalutamide agonism of mutant F877L AR. Further, enzalutamide treatment of AR F877L-expressing cell lines recapitulated the effects of androgen activation of F877L AR or wild-type AR. Because the BET bromodomain inhibitor JQ-1 was previously shown to block androgen activation of wild-type AR, we tested JQ-1 in AR F877L-expressing CRPC models. We determined that JQ-1 suppressed androgen or enzalutamide activation of mutant F877L AR and suppressed growth of mutant F877L AR CRPC tumors in vivo, demonstrating a new strategy to treat tumors harboring this mutation. PMID:27276681
Studies of the hormonal control of postnatal testicular descent in the rat.
Spencer, J R; Vaughan, E D; Imperato-McGinley, J
1993-03-01
Dihydrotestosterone is believed to control the transinguinal phase of testicular descent based on hormonal manipulation studies performed in postnatal rats. In the present study, these hormonal manipulation experiments were repeated, and the results were compared with those obtained using the antiandrogens flutamide and cyproterone acetate. 17 beta-estradiol completely blocked testicular descent, but testosterone and dihydrotestosterone were equally effective in reversing this inhibition. Neither flutamide nor cyproterone acetate prevented testicular descent in postnatal rats despite marked peripheral antiandrogenic action. Further analysis of the data revealed a correlation between testicular size and descent. Androgen receptor blockade did not produce a marked reduction in testicular size and consequently did not prevent testicular descent, whereas estradiol alone caused marked testicular atrophy and testicular maldescent. Reduction of the estradiol dosage or concomitant administration of androgens or human chorionic gonadotropin resulted in both increased testicular size and degree of descent. These data suggest that growth of the neonatal rat testis may contribute to its passage into the scrotum.
Synergistic effects of androgen and estrogen on the mouse uterus and mammary gland.
Zhang, Jian; Sun, Yibin; Liu, Yunhai; Sun, Yi; Liao, Dezhong Joshua
2004-10-01
Many studies have suggested that elevated estrogens and androgens may be etiologically related to the development of breast cancer, endometrial cancer and uterine leiomyomas. We and other investigators have previously shown that estrogen and androgen are synergistic in the induction of mammary carcinogenesis in the Noble rat. However, the mechanisms behind the synergy is unknown, and it is unclear whether such synergy is unique for the Noble rat and for the mammary gland. In this study we treated female FVB mice with 17beta-estradiol (E2) and 5alpha-dihydrotestosterone-bezonate (DHT-B), alone and in combination, using silastic tubing for 2-7 months. The results showed that DHT-B alone induced proliferation of uterine endometrial epithelium and myometrial smooth muscle cells, whereas E2 alone induced much more pronounced growth of endometrial epithelium without affecting smooth muscle cells. Combined treatment with E2+DHT-B caused an even more severe hyperplasia of endometrial epithelium and myometrial muscle cells, compared with the treatment with each hormone alone. Uterine leiomyomas were observed in 2 of 6 mice at 7 months of combined treatment but not in any of 6 or 7 mice receiving each single hormone. DHT-B alone induced growth and secretion of mammary ductal cells, as well as growth of mammary stroma. E2 alone stimulated much more pronounced growth of both ductal cells and alveolar cells and secretion of alveolar cells, but had no effect on mammary stroma. Treatment with both E2 and DHT-B caused more severe hyperplasia of mammary ducts and alveoli, compared to the treatment with each hormone alone. Intraductal hyperplasia occurred early and frequently in the E2+DHT-B- treated mice, but no mammary tumors were observed. These results suggest that E2 and DHT-B have synergistic effects on the growth of uterine endometrial epithelium and myometrial muscle cells, as well as mammary epithelial ducts and alveoli.
Gong, J; Zhu, J; Goodman, O B; Pestell, R G; Schlegel, P N; Nanus, D M; Shen, R
2006-03-30
Androgen receptor signaling in prostate cancer cells is augmented by the androgen receptor (AR) coactivator p300, which transactivates and acetylates the AR in the presence of dihydrotestosterone (DHT). As prostate cancer (PC) cells progress to androgen independence, AR signaling remains intact, indicating that other factors stimulate AR activities in the absence of androgen. We previously reported that neuropeptide growth factors could transactivate the AR in the presence of very low concentrations of DHT. Here, we examine the involvement of p300 in neuropeptide activation of AR signaling. Transfection of increasing concentrations of p300 in the presence of bombesin into PC-3 cells resulted in a linear increase in AR transactivation, suggesting that p300 acts as a coactivator in neuropeptide-mediated AR transactivation. P300 is endowed with histone acetyltransferase (HAT) activity. Therefore, we examine the effect of bombesin on p300 HAT activity. At 4 h after the addition of bombesin, p300 HAT activity increased 2.0-fold (P<0.01). Incubation with neutral endopeptidase, which degrades bombesin, or bombesin receptor antagonists blocked bombesin-induced p300 HAT activity. To explore the potential signaling pathways involved in bombesin-induced p300 HAT activity, we examined Src and PKCdelta pathways that mediate bombesin signaling. Inhibitors of Src kinase activity or Src kinase siRNA blocked bombesin-induced p300 HAT activity, whereas PKCdelta inhibitors or PKCdelta siRNA significantly increased bombesin-induced p300 HAT activity suggesting that Src kinase and PKCdelta kinase are involved in the regulation of p300 HAT activity. As AR is acetylated in the presence of 100 nM DHT, we next examined whether bombesin-induced p300 HAT activity would result in enhanced AR acetylation. Bombesin-induced AR acetylation at the same motif KLKK observed in DHT-induced acetylation. Elimination of p300 using p300 siRNA reduced AR acetylation, demonstrating that AR acetylation was
Characteristics of Men Who Report Persistent Sexual Symptoms After Finasteride Use for Hair Loss.
Basaria, Shehzad; Jasuja, Ravi; Huang, Grace; Wharton, Whitney; Pan, Hong; Pencina, Karol; Li, Zhuoying; Travison, Thomas G; Bhawan, Jag; Gonthier, Renaud; Labrie, Fernand; Dury, Alain Y; Serra, Carlo; Papazian, Allen; O'Leary, Michael; Amr, Sami; Storer, Thomas W; Stern, Emily; Bhasin, Shalender
2016-12-01
Some men who use finasteride for hair loss report persistent sexual and other symptoms after discontinuing finasteride therapy. To determine whether these persistent symptoms after discontinuation of finasteride use are due to androgen deficiency, decreased peripheral androgen action, or persistent inhibition of steroid 5α-reductase (SRD5A) enzymes. Finasteride users, who reported persistent sexual symptoms after discontinuing finasteride (group 1); age-matched finasteride users who did not report sexual symptoms (group 2); and healthy men who had never used finasteride (group 3). Sexual function, mood, affect, cognition, hormone levels, body composition, functional magnetic resonance imaging (fMRI) response to sexually and affectively valenced stimuli, nucleotide sequences of androgen receptor (AR), SRD5A1, and SRD5A2; expression levels of androgen-dependent genes in skin. Academic medical center. Symptomatic finasteride users were similar in body composition, strength, and nucleotide sequences of AR, SRD5A1, and SRD5A2 genes to asymptomatic finasteride users and nonusers. Symptomatic finasteride users had impaired sexual function, higher depression scores, a more negative affectivity balance, and more cognitive complaints than men in groups 2 and 3 but had normal objectively assessed cognitive function. Testosterone, dihydrotestosterone, 5α-androstane-3α,17β-diol-glucuronide, testosterone to dihydrotestosterone and androsterone glucuronide to etiocholanolone glucuronide ratios, and markers of peripheral androgen action and expression levels of AR-dependent genes in skin did not differ among groups. fMRI blood oxygen level-dependent responses to erotic and nonerotic stimuli revealed abnormal function in brain circuitry linked to sexual arousal and major depression. We found no evidence of androgen deficiency, decreased peripheral androgen action, or persistent peripheral inhibition of SRD5A in men with persistent sexual symptoms after finasteride use
Yang, Mei; Li, Jianhua; An, Yulin; Zhang, Shuiwen
2015-10-01
Androgens have essential roles in the regulation of follicular development and female fertility. Androgen excess is the leading defect in polycystic ovary syndrome (PCOS) patients and involved in the ovarian dysfunction. The aim of this study was to elucidate the regarding regulatory role of androgen in the follicular development of female mouse. Immunohistochemical staining and Western blot analyses were performed to detect androgen receptor (AR) and Connexin 43 (Cx43) expression in ovaries from both control and testosterone-treated group mice. In this study, localizations of AR and Cx43 were dramatically altered in testosterone-treated mouse ovaries. In addition, AR expression was significantly increased, whereas Cx43 expression was markedly decreased after testosterone treatment. Alterations of AR and Cx43 expression by testosterone with concomitant reduction of MII oocytes. Overall, these results suggest the involvement of androgen in the regulation of AR and Cx43 localizations in mouse ovary. Alterations of AR and Cx43 expression by testosterone may affect normal folliculogenesis. Together these findings will enable us to begin understanding the important roles of AR and Cx43 actions in the regulation of follicular development, as well as providing insights into the role of AR and Cx43 actions in the androgen-associated reproductive diseases such as PCOS. Copyright © 2015 Elsevier Ltd. All rights reserved.
Goodman, Neil F; Cobin, Rhoda H; Futterweit, Walter; Glueck, Jennifer S; Legro, Richard S; Carmina, Enrico
2015-11-01
, alopecia, and acne. Cycle length >35 days suggests chronic anovulation, but cycle length slightly longer than normal (32 to 35 days) or slightly irregular (32 to 35-36 days) needs assessment for ovulatory dysfunction. Ovulatory dysfunction is associated with increased prevalence of endometrial hyperplasia and endometrial cancer, in addition to infertility. In PCOS, hirsutism develops gradually and intensifies with weight gain. In the neoplastic virilizing states, hirsutism is of rapid onset, usually associated with clitoromegaly and oligomenorrhea. Girls with severe acne or acne resistant to oral and topical agents, including isotretinoin (Accutane), may have a 40% likelihood of developing PCOS. Hair loss patterns are variable in women with hyperandrogenemia, typically the vertex, crown or diffuse pattern, whereas women with more severe hyperandrogenemia may see bitemporal hair loss and loss of the frontal hairline. Oral contraceptives (OCPs) can effectively lower androgens and block the effect of androgens via suppression of ovarian androgen production and by increasing sex hormone-binding globulin. Physiologic doses of dexamethasone or prednisone can directly lower adrenal androgen output. Anti-androgens can be used to block the effects of androgen in the pilosebaceous unit or in the hair follicle. Anti-androgen therapy works through competitive antagonism of the androgen receptor (spironolactone, cyproterone acetate, flutamide) or inhibition of 5α-reductase (finasteride) to prevent the conversion of T to its more potent form, 5α-dihydrotestosterone. The choice of antiandrogen therapy is guided by symptoms. The diagnosis of PCOS in adolescents is particularly challenging given significant age and developmental issues in this group. Management of infertility in women with PCOS requires an understanding of the pathophysiology of anovulation as well as currently available treatments. Many features of PCOS, including acne, menstrual irregularities, and hyperinsulinemia
Hara, Noboru; Ishizaki, Fumio; Saito, Toshihiro; Nishiyama, Tsutomu; Kawasaki, Takashi; Takahashi, Kota
2013-02-01
To elucidate the mechanism of the androgen deprivation therapy (ADT)-related decrease in lean body mass (LBM). The LBM and blood samples were studied before and after 6 months of ADT in 72 patients with localized prostate cancer. The LBM was assessed using a foot-to-foot bioelectrical impedance analyzer. Before ADT, the LBM correlated with none of the serum sex steroid levels; however, it correlated closely with serum 5α-androstane-3α,17β-diol glucuronide (Spearman's rank correlation coefficient = 0.409, P = .001) and insulin-like growth factor-1 (IGF-I, Spearman's rank correlation coefficient = 0.329, P = .005). After ADT, the LBM decreased by 0.9% (P = .036), and the serum testosterone and dihydrotestosterone had decreased by 96.8% and 94.3%, respectively (P <.001 for both), and the IGF-I had increased by 11.6% (from 19.9 to 22.2 nmol/L, P = .001). The serum 1,25-dihydroxyvitamin D3 [1,25(OH)2D] levels decreased after ADT by 9.8% (from 66.2 to 59.7 pg/mL, P = .008), and the post-treatment LBM correlated inversely with 1,25(OH)2D (Spearman's rank correlation coefficient = -0.343, P = .003). The post-treatment LBM was dissociated with 5α-androstane-3α,17β-diol glucuronide and IGF-I. The pretreatment and post-treatment LBMs both correlated inversely with serum sex hormone-binding globulin (P = .024 and P = .016, respectively). The deficiency in androgen levels was suggested to be a link to the ADT-related decrease in LBM; the androgen metabolite 5α-androstane-3α,17β-diol glucuronide has a potential value for assessing the LBM in untreated men. IGF-I also promotes muscle building and is positively regulated during ADT. Sex hormone-binding globulin possibly accelerates the ADT-related decrease in LBM. Although the mechanism for the decrease in 1,25(OH)2D and its inverse correlation with LBM during ADT is unclear, 1,25(OH)2D might be a biomarker reflecting the ADT-related decrease in LBM. Copyright © 2013 Elsevier Inc. All rights reserved.
Osteopenia as a feature of the androgen insensitivity syndrome.
Soule, S G; Conway, G; Prelevic, G M; Prentice, M; Ginsburg, J; Jacobs, H S
1995-12-01
The syndrome of androgen insensitivity, a paradigm of a hormone resistance syndrome, manifests as failure of masculinization despite normal or high concentrations of serum testosterone. The defect in these 46 XY patients resides in the androgen receptor gene, with consequent defective androgen action and abnormal sexual differentiation. We sought to evaluate whether the adverse sequelae of androgen resistance may extend to skeletal tissue by measuring bone mineral density in six patients with androgen insensitivity. A cross-sectional retrospective study. Bone mineral density was measured by means of a Dexa (Hologic QDR 1000 scanner). The diagnosis of androgen insensitivity was confirmed in each patient by karyotype and assay of sex hormones. The five adult patients with androgen insensitivity had been exposed to both defective androgen action and variable periods of oestrogen deficiency. The latter resulted from the low circulating oestrogen concentrations (for premenopausal females) before gonadectomy and inadequate oestrogen replacement after gonadectomy. All five adults with androgen insensitivity had osteopenia in both the lumbar spine (T-score -1.52 to -3.85) and femoral neck (T-score -1.34 to -4.91). Osteopenia in patients with androgen insensitivity may relate to defective androgen action, oestrogen deficiency or a combination of the two. These observations have implications for the management of patients with androgen insensitivity and may provide insight into the effects of androgens on the female as well as the male skeleton.
Hanada, Keigo; Furuya, Kazuyuki; Yamamoto, Noriko; Nejishima, Hiroaki; Ichikawa, Kiyonoshin; Nakamura, Tsutomu; Miyakawa, Motonori; Amano, Seiji; Sumita, Yuji; Oguro, Nao
2003-11-01
A novel nonsteroidal androgen receptor (AR) binder, S-40503, was successfully generated in order to develop selective androgen receptor modulators (SARMs). We evaluated the binding specificity for nuclear receptors (NRs) and osteoanabolic activities of S-40503 in comparison with a natural nonaromatizable steroid, 5alpha-dihydrotestosterone (DHT). The compound preferentially bound to AR with nanomolar affinity among NRs. When S-40503 was administrated into orchiectomized (ORX) rats for 4 weeks, bone mineral density (BMD) of femur and muscle weight of levator ani were increased as markedly as DHT, but prostate weight was not elevated over the normal at any doses tested. In contrast, DHT administration caused about 1.5-fold increase in prostate weight. The reduced virilizing activity was clearly evident from the result that 4-week treatment of normal rats with S-40503 showed no enlargement of prostate. To confirm the bone anabolic effect, S-40503 was given to ovariectomized (OVX) rats for 2 months. The compound significantly increased the BMD and biomechanical strength of femoral cortical bone, whereas estrogen, anti-bone resorptive hormone, did not. The increase in periosteal mineral apposition rate (MAR) of the femur revealed direct bone formation activity of S-40503. It was unlikely that the osteoanabolic effect of the compound was attribute to the enhancement of muscle mass, because immobilized ORX rats treated with S-40503 showed a marked increase in BMD of tibial cortical bone without any actions on the surrounding muscle tissue. Collectively, our novel compound served as a prototype for SARMs, which had unique tissue selectivity with high potency for bone formation and lower impact upon sex accessory tissues.
Opoku-Acheampong, Alexander B.; Nelsen, Michelle K.; Unis, Dave; Lindshield, Brian L.
2012-01-01
Background 5α-reductase 1 (5αR1) and 5α-reductase 2 (5αR2) convert testosterone into the more potent androgen dihydrotestosterone. 5αR2 is the main isoenzyme in normal prostate tissue; however, most prostate tumors have increased 5αR1 and decreased 5αR2 expression. Previously, finasteride (5αR2 inhibitor) treatment begun 3 weeks post-tumor implantation had no effect on Dunning R3327-H rat prostate tumor growth. We believe the tumor compensated for finasteride treatment by increasing tumor 5αR1 expression or activity. We hypothesize that finasteride treatment would not significantly alter tumor growth even if begun before tumor implantation, whereas dutasteride (5αR1 and 5αR2 inhibitor) treatment would decrease tumor growth regardless of whether treatment was initiated before or after tumor implantation. Methodology/Principal Findings Sixty 8-week-old male nude mice were randomized to Control, Pre- and Post-Finasteride, and Pre- and Post-Dutasteride (83.3 mg drug/kg diet) diet groups. Pre- and post-groups began their treatment diets 1–2 weeks prior to or 3 weeks after subcutaneous injection of 1×105 WPE1-NA22 human prostate cancer cells, respectively. Tumors were allowed to grow for 22 weeks; tumor areas, body weights, and food intakes were measured weekly. At study's conclusion, prostate and seminal vesicle weights were significantly decreased in all treatment groups versus the control; dutasteride intake significantly decreased seminal vesicle weights compared to finasteride intake. No differences were measured in final tumor areas or tumor weights between groups, likely due to poor tumor growth. In follow-up studies, proliferation of WPE1-NA22 prostate cancer cells and parent line RWPE-1 prostate epithelial cells were unaltered by treatment with testosterone, dihydrotestosterone, or mibolerone, suggesting that these cell lines are not androgen-sensitive. Conclusion The lack of response of WPE1-NA22 prostate cancer cells to androgen treatment may
Bailey, Kathy; Yazdi, Tahmineh; Masharani, Umesh; Tyrrell, Blake; Butch, Anthony; Schaufele, Fred
2016-01-01
Testosterone (T) and related androgens are performance enhancing drugs (PEDs) abused by some athletes to gain competitive advantage. To monitor unauthorized androgen abuse, doping control programs use mass spectrometry (MS) to detect androgens, synthetic anabolic-androgenic steroids (AASs) and their metabolites in an athlete's urine. AASs of unknown composition will not be detected by these procedures. Since AASs achieve their anabolic effects by activating the Androgen Receptor (AR), cell-based bioassays that measure the effect of a urine sample on AR activity are under investigation as complementary, pan-androgen detection methods. We evaluated an AR BioAssay as a monitor for androgen activity in urine pre-treated with glucuronidase, which releases T from the inactive T-glucuronide that predominates in urine. AR BioAssay activity levels were expressed as 'T-equivalent' concentrations by comparison to a T dose response curve. The T-equivalent concentrations of androgens in the urine of hypogonadal participants supplemented with T (in whom all androgenic activity should arise from T) were quantitatively identical to the T measurements conducted by MS at the UCLA Olympic Analytical Laboratory (0.96 ± 0.22). All 17 AASs studied were active in the AR BioAssay; other steroids were inactive. 12 metabolites of 10 commonly abused AASs, which are used for MS monitoring of AAS doping because of their prolonged presence in urine, had reduced or no AR BioAssay activity. Thus, the AR BioAssay can accurately and inexpensively monitor T, but its ability to monitor urinary AASs will be limited to a period immediately following doping in which the active AASs remain intact.
Kang, Kyungsu; Peng, Lei; Jung, Yu-Jin; Kim, Joo Yeon; Lee, Eun Ha; Lee, Hee Ju; Kim, Sang Min; Sung, Sang Hyun; Pan, Cheol-Ho; Choi, Yongsoo
2018-02-01
To develop a high-throughput screening system to measure the conversion of testosterone to dihydrotestosterone (DHT) in cultured human prostate cancer cells using turbulent flow chromatography liquid chromatography-triple quadrupole mass spectrometry (TFC-LC-TQMS). After optimizing the cell reaction system, this method demonstrated a screening capability of 103 samples, including 78 single compounds and 25 extracts, in less than 12 h without manual sample preparation. Consequently, fucoxanthin, phenethyl caffeate, and Curcuma longa L. extract were validated as bioactive chemicals that inhibited DHT production in cultured DU145 cells. In addition, naringenin boosted DHT production in DU145 cells. The method can facilitate the discovery of bioactive chemicals that modulate the DHT production, and four phytochemicals are potential candidates of nutraceuticals to adjust DHT levels in male hormonal dysfunction.
Involvement of androgens in ovarian health and disease
Lebbe, M.; Woodruff, T.K.
2013-01-01
In women, ovary and adrenal gland produce androgens. Androgens are essential drivers of the primordial to antral follicle development, prior to serving as substrate for estrogen production in the later stages of folliculogenesis. Androgens play a crucial role in the follicular–stromal intertalk by fine tuning the extracellular matrix and vessel content of the ovarian stroma. Local auto-and paracrine factors regulate androgen synthesis in the pre-antral follicle. Androgen excess is a hallmark of polycystic ovary syndrome and is a key contributor in the exaggerated antral follicle formation, stromal hyperplasia and hypervascularity. Hyperandrogenaemia overrides the follicular–stromal dialog, resulting in follicular arrest and disturbed ovulation. On the other hand, androgen deficiency is likely to have a negative impact on fertility as well, and further research is needed to examine the benefits of androgen-replacement therapy in subfertility. PMID:24026057
Correa, Ricardo G; Krajewska, Maryla; Ware, Carl F; Gerlic, Motti; Reed, John C
2014-03-30
Prostate cancer (PCa) is among the leading causes of cancer-related death in men. Androgen receptor (AR) signaling plays a seminal role in prostate development and homeostasis, and dysregulation of this pathway is intimately linked to prostate cancer pathogenesis and progression. Here, we identify the cytosolic NLR-related protein NWD1 as a novel modulator of AR signaling. We determined that expression of NWD1 becomes elevated during prostate cancer progression, based on analysis of primary tumor specimens. Experiments with cultured cells showed that NWD1 expression is up-regulated by the sex-determining region Y (SRY) family proteins. Gene silencing procedures, in conjunction with transcriptional profiling, showed that NWD1 is required for expression of PDEF (prostate-derived Ets factor), which is known to bind and co-regulate AR. Of note, NWD1 modulates AR protein levels. Depleting NWD1 in PCa cell lines reduces AR levels and suppresses activity of androgen-driven reporter genes. NWD1 knockdown potently suppressed growth of androgen-dependent LNCaP prostate cancer cells, thus showing its functional importance in an AR-dependent tumor cell model. Proteomic analysis suggested that NWD1 associates with various molecular chaperones commonly related to AR complexes. Altogether, these data suggest a role for tumor-associated over-expression of NWD1 in dysregulation of AR signaling in PCa.
Jia, Lin; Wu, Dinglan; Wang, Yuliang; You, Wenxing; Wang, Zhu; Xiao, Lijia; Cai, Ganhui; Xu, Zhenyu; Zou, Chang; Wang, Fei; Teoh, Jeremy Yuen-Chun; Ng, Chi-Fai; Yu, Shan; Chan, Franky L
2018-03-20
The metastatic castration-resistant prostate cancer (CRPC) is a lethal form of prostate cancer, in which the expression of androgen receptor (AR) is highly heterogeneous. Indeed, lower AR expression and attenuated AR signature activity is shown in CRPC tissues, especially in the subset of neuroendocrine prostate cancer (NEPC) and prostate cancer stem-like cells (PCSCs). However, the significance of AR downregulation in androgen insensitivity and de-differentiation of tumor cells in CRPC is poorly understood and much neglected. Our previous study shows that the orphan nuclear receptor TLX (NR2E1), which is upregulated in prostate cancer, plays an oncogenic role in prostate carcinogenesis by suppressing oncogene-induced senescence. In the present study, we further established that TLX exhibited an increased expression in metastatic CRPC. Further analyses showed that overexpression of TLX could confer resistance to androgen deprivation and anti-androgen in androgen-dependent prostate cancer cells in vitro and in vivo, whereas knockdown of endogenous TLX could potentiate the sensitivity to androgen deprivation and anti-androgen in prostate cancer cells. Our study revealed that the TLX-induced resistance to androgen deprivation and anti-androgen was mediated through its direct suppression of AR gene transcription and signaling in both androgen-stimulated and -unstimulated prostate cancer cells. We also characterized that TLX could bind directly to AR promoter and repress AR transcription by recruitment of histone modifiers, including HDAC1, HDAC3, and LSD1. Together, our present study shows, for the first time, that TLX can contribute to androgen insensitivity in CRPC via repression of AR gene transcription and signaling, and also implicates that targeting the druggable TLX may have a potential therapeutic significance in CRPC management, particularly in NEPC and PCSCs.
Androgen circle of polycystic ovary syndrome.
Homburg, Roy
2009-07-01
Although the aetiology of polycystic ovary syndrome (PCOS) is still not known and the search for causative genes is proving elusive, it is generally agreed that hyperandrogenism is at the heart of the syndrome. Here, it is proposed that excess androgens are the root cause of PCOS starting from their influence on the female fetus in programming gene expression, producing the characteristic signs and symptoms which are then exacerbated by a propagation of excess ovarian androgen production from multiple small follicles, anovulation and insulin resistance in the reproductive life-span, thus setting up a vicious perpetual circle of androgen excess. This opinion paper, rather than being a full-scale review, is intentionally biased in support of this hypothesis that androgen excess is the 'root of all evil' in PCOS; in the hope that its acceptance could lead to more direct treatment of the syndrome in all its facets rather than the symptomatic treatment of side effects of androgen excess that we are addressing today.
Morimoto, Megumi; Amano, Yuichiro; Oka, Masahiro; Harada, Ayako; Fujita, Hisashi; Hikichi, Yukiko; Tozawa, Ryuichi; Yamaoka, Masuo
2017-01-01
Sarcopenia and cachexia present characteristic features of a decrease in skeletal muscle mass and strength, anorexia, and lack of motivation. Treatments for these diseases have not yet been established, although selective androgen receptor modulators (SARMs) are considered as therapeutic targets. We previously reported that a novel SARM compound, SARM-2f, exhibits anabolic effect on muscles, with less stimulatory effect on prostate weight compared with testosterone, in rat Hershberger assays and cancer cachexia models. In this study, we studied the mechanism of action for SARM-2f selectivity and also assessed whether the muscle increase by this compound might lead to improvement of muscle function and physical activity. First, we examined the tissue distribution of SARM-2f. Tissue concentration was 1.2-, 1.6-, and 1.9-fold as high as the plasma concentration in the levator ani muscle, brain, and prostate, respectively. This result showed that the tissue-selective pharmacological effect did not depend on SARM-2f concentration in the tissues. The ability of SARM-2f to influence androgen receptor (AR)-mediated transcriptional activation was examined by reporter assays using human normal prostate epithelial cells (PrEC) and skeletal muscle cells (SKMC). SARM-2f exerted higher activity against AR in SKMC than in PrEC. Mammalian two hybrid assays showed different co-factor recruitment patterns between SARM-2f and dihydrotestosterone. Next, we studied the effect of SARM-2f on motivation and physical functions such as sexual behavior and motor activities in castrated rat or mouse models. SARM-2f restored the sexual behavior that was lost by castration in male rats. SARM-2f also increased voluntary running distance and locomotor activities. These results suggest that tissue-specific AR regulation by SARM-2f, but not tissue distribution, might account for its tissue specific androgenic effect, and that the muscle mass increase by SARM-2f leads to improvement of physical
Therapeutic androgen receptor ligands
Allan, George F.; Sui, Zhihua
2003-01-01
In the past several years, the concept of tissue-selective nuclear receptor ligands has emerged. This concept has come to fruition with estrogens, with the successful marketing of drugs such as raloxifene. The discovery of raloxifene and other selective estrogen receptor modulators (SERMs) has raised the possibility of generating selective compounds for other pathways, including androgens (that is, selective androgen receptor modulators, or SARMs). PMID:16604181
Androgens in health and disease: An overview
Jordan, Cynthia L.; DonCarlos, Lydia
2009-01-01
This special issue of Hormones and Behavior, “Androgens in health and disease: new insights into roles and mechanisms of action,” is prompted by a number of relatively recent findings that androgens affect brain morphology and function in ways not previously or widely appreciated. Moreover, recent results also make it clear that androgens utilize a variety of signaling molecules to exert their effects on the brain, which may or may not depend on the classic nuclear androgen receptor (AR). The papers in this issue underscore these two points. This overview is not intended as a comprehensive review of androgen action on the nervous system, since the papers in this issue serve that purpose, but rather to frame the basic issues and themes that tie these papers together. The sum effect of the stories told in this issue encourages us to broaden and refocus our view of androgen action on brain and behavior—to recognize that androgens affect many aspects of brain structure and function throughout the lifespan, from shaping its sexual phenotype to influencing its propensity for disease and repair, and that at least some of these actions are exerted via non-classical modes of action that in many cases were first identified in non-neural tissue or cells. PMID:18407273
The androgen receptor gene mutations database.
Gottlieb, B; Trifiro, M; Lumbroso, R; Vasiliou, D M; Pinsky, L
1996-01-01
The current version of the androgen receptor (AR) gene mutations database is described. We have added (if available) data on the androgen binding phenotype of the mutant AR, the clinical phenotype of the affected persons, the family history and whether the pathogenicity of a mutation has been proven. Exonic mutations are now listed in 5'-->3' sequence regardless of type and single base pair changes are presented in codon context. Splice site and intronic mutations are listed separately. The database has allowed us to substantiate and amplify the observation of mutational hot spots within exons encoding the AR androgen binding domain. The database is available from EML (ftp://www.ebi.ac.uk/pub/databases/androgen) or as a Macintosh Filemaker file (MC33@musica.mcgill.ca).
Kato, Yuiko; Ochiai, Kazuhiko; Kawakami, Shota; Nakao, Nobuhiro; Azakami, Daigo; Bonkobara, Makoto; Michishita, Masaki; Morimatsu, Masami; Watanabe, Masami; Omi, Toshinori
2017-06-09
The pathological condition of canine prostate cancer resembles that of human androgen-independent prostate cancer. Both canine and human androgen receptor (AR) signalling are inhibited by overexpression of the dimerized co-chaperone small glutamine-rich tetratricopeptide repeat-containing protein α (SGTA), which is considered to cause the development of androgen-independency. Reduced expression in immortalised cells (REIC/Dkk-3) interferes with SGTA dimerization and rescues AR signalling. This study aimed to assess the effects of REIC/Dkk-3 and SGTA interactions on AR signalling in the canine androgen-independent prostate cancer cell line CHP-1. Mammalian two-hybrid and Halo-tagged pull-down assays showed that canine REIC/Dkk-3 interacted with SGTA and interfered with SGTA dimerization. Additionally, reporter assays revealed that canine REIC/Dkk-3 restored AR signalling in both human and canine androgen-independent prostate cancer cells. Therefore, we confirmed the interaction between canine SGTA and REIC/Dkk-3, as well as their role in AR signalling. Our results suggest that this interaction might contribute to the development of a novel strategy for androgen-independent prostate cancer treatment. Moreover, we established the canine androgen-independent prostate cancer model as a suitable animal model for the study of this type of treatment-refractory human cancer.
Mostaghel, Elahe A.; Morgan, Andrew; Zhang, Xiaotun; Marck, Brett T.; Xia, Jing; Hunter-Merrill, Rachel; Gulati, Roman; Plymate, Stephen; Vessella, Robert L.; Corey, Eva; Higano, Celestia S.; Matsumoto, Alvin M.; Montgomery, R. Bruce; Nelson, Peter S.
2014-01-01
Background Factors influencing differential responses of prostate tumors to androgen receptor (AR) axis-directed therapeutics are poorly understood, and predictors of treatment efficacy are needed. We hypothesized that the efficacy of inhibiting DHT ligand synthesis would associate with intra-tumoral androgen ratios indicative of relative dependence on DHT-mediated growth. Methods We characterized two androgen-sensitive prostate cancer xenograft models after androgen suppression by castration in combination with the SRD5A inhibitor, dutasteride, as well as a panel of castration resistant metastases obtained via rapid autopsy. Results In LuCaP35 tumors (intra-tumoral T:DHT ratio 2∶1) dutasteride suppressed DHT to 0.02 ng/gm and prolonged survival vs. castration alone (337 vs.152 days, HR 2.8, p = 0.0015). In LuCaP96 tumors (T:DHT 10∶1), survival was not improved despite similar DHT reduction (0.02 ng/gm). LuCaP35 demonstrated higher expression of steroid biosynthetic enzymes maintaining DHT levels (5-fold higher SRD5A1, 41 fold higher, 99-fold higher RL-HSD, p<0.0001 for both), reconstitution of intra-tumoral DHT (to ∼30% of untreated tumors), and ∼2 fold increased expression of full length AR. In contrast, LuCaP96 demonstrated higher levels of steroid catabolizing enzymes (6.9-fold higher AKR1C2, 3000-fold higher UGT2B15, p = 0.002 and p<0.0001 respectively), persistent suppression of intra-tumoral DHT, and 6–8 fold induction of full length AR and the ligand independent V7 AR splice variant. Human metastases demonstrated bio-active androgen levels and AR full length and AR splice-variant expression consistent with the range observed in xenografts. Conclusions Intrinsic differences in basal steroidogenesis, as well as variable expression of full length and splice-variant AR, associate with response and resistance to pre-receptor AR ligand suppression. Expression of steroidogenic enzymes and AR isoforms may serve as potential biomarkers of
Prenatal and adult androgen activities in alcohol dependence.
Lenz, B; Mühle, C; Braun, B; Weinland, C; Bouna-Pyrrou, P; Behrens, J; Kubis, S; Mikolaiczik, K; Muschler, M-R; Saigali, S; Sibach, M; Tanovska, P; Huber, S E; Hoppe, U; Eichler, A; Heinrich, H; Moll, G H; Engel, A; Goecke, T W; Beckmann, M W; Fasching, P A; Müller, C P; Kornhuber, J
2017-07-01
Alcohol dependence is more prevalent in men than in women. The evidence for how prenatal and adult androgens influence alcohol dependence is limited. We investigated the effects of prenatal and adult androgen activity on alcohol dependence. Moreover, we studied how the behaviours of pregnant women affect their children's prenatal androgen load. We quantified prenatal androgen markers (e.g., second-to-fourth finger length ratio [2D : 4D]) and blood androgens in 200 early-abstinent alcohol-dependent in-patients and 240 controls (2013-2015, including a 12-month follow-up). We also surveyed 134 women during pregnancy (2005-2007) and measured the 2D : 4D of their children (2013-2016). The prenatal androgen loads were higher in the male alcohol-dependent patients compared to the controls (lower 2D : 4D, P = 0.004) and correlated positively with the patients' liver transaminase activities (P < 0.001) and alcohol withdrawal severity (P = 0.019). Higher prenatal androgen loads and increasing androgen levels during withdrawal predicted earlier and more frequent 12-month hospital readmission in alcohol-dependent patients (P < 0.005). Moreover, stress levels (P = 0.002), alcohol (P = 0.010) and tobacco consumption (P = 0.017), and lifetime stressors (P = 0.019) of women during pregnancy related positively to their children's prenatal androgen loads (lower 2D : 4D). Androgen activities in alcohol-dependent patients and behaviours of pregnant women represent novel preventive and therapeutic targets of alcohol dependence. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Potential anabolic effects of androgens on bone.
Kearns, Ann E; Khosla, Sundeep
2004-04-01
Sex steroid hormones are essential to normal skeletal growth and maintenance throughout life in both men and women. The importance of estrogens to bone health in women becomes obvious at menopause when estrogen deficiency occurs and results in accelerated bone loss. After menopause, estrogen deficiency results in drastic changes in the androgen-estrogen ratio. Thus, the relative importance of androgens after menopause may increase. Androgens also appear to be important for bone health in pre-menopausal women. Evidence from human, animal, and laboratory studies is leading to a better understanding of the effects of androgens on bone in women.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kharlyngdoh, Joubert Banjop; Asnake, Solomon; Prad
Point mutations in the AR ligand-binding domain (LBD) can result in altered AR structures leading to changes of ligand specificity and functions. AR mutations associated to prostate cancer (PCa) have been shown to result in receptor activation by non-androgenic substances and anti-androgenic drugs. Two AR mutations known to alter the function of anti-androgens are the AR{sub T877A} mutation, which is frequently detected mutation in PCa tumors and the AR{sub W741C} that is rare and has been derived in vitro following exposure of cells to the anti-androgen bicalutamide. AR activation by non-androgenic environmental substances has been suggested to affect PCa progression.more » In the present study we investigated the effect of AR mutations (AR{sub W741C} and AR{sub T877A}) on the transcriptional activation following exposure of cells to an androgenic brominated flame retardant, 1,2-dibromo-4-(1,2 dibromoethyl) cyclohexane (TBECH, also named DBE-DBCH). The AR mutations resulted in higher interaction energies and increased transcriptional activation in response to TBECH diastereomer exposures. The AR{sub T877A} mutation rendered AR highly responsive to low levels of DHT and TBECH and led to increased AR nuclear translocation. Gene expression analysis showed a stronger induction of AR target genes in LNCaP cells (AR{sub T877A}) compared to T-47D cells (AR{sub WT}) following TBECH exposure. Furthermore, AR knockdown experiments confirmed the AR dependency of these responses. The higher sensitivity of AR{sub T877A} and AR{sub W741C} to low levels of TBECH suggests that cells with these AR mutations are more susceptible to androgenic endocrine disrupters. - Highlights: • TBECH, is an endocrine disrupting compound that differ in activity depending on AR structure and sequence. • TBECH interaction with the human AR-LBD containing the mutations W741C and T877A is increased compared to the wild type receptor • The mutations, W741C and T877A, are more potent than the
A Mathematical Model of Intermittent Androgen Suppression for Prostate Cancer
NASA Astrophysics Data System (ADS)
Ideta, Aiko Miyamura; Tanaka, Gouhei; Takeuchi, Takumi; Aihara, Kazuyuki
2008-12-01
For several decades, androgen suppression has been the principal modality for treatment of advanced prostate cancer. Although the androgen deprivation is initially effective, most patients experience a relapse within several years due to the proliferation of so-called androgen-independent tumor cells. Bruchovsky et al. suggested in animal models that intermittent androgen suppression (IAS) can prolong the time to relapse when compared with continuous androgen suppression (CAS). Therefore, IAS has been expected to enhance clinical efficacy in conjunction with reduction in adverse effects and improvement in quality of life of patients during off-treatment periods. This paper presents a mathematical model that describes the growth of a prostate tumor under IAS therapy based on monitoring of the serum prostate-specific antigen (PSA). By treating the cancer tumor as a mixed assembly of androgen-dependent and androgen-independent cells, we investigate the difference between CAS and IAS with respect to factors affecting an androgen-independent relapse. Numerical and bifurcation analyses show how the tumor growth and the relapse time are influenced by the net growth rate of the androgen-independent cells, a protocol of the IAS therapy, and the mutation rate from androgen-dependent cells to androgen-independent ones.
Familial male pseudohermaphroditism and testicular descent in the racoon dog (Nyctereutes).
Fentener van Vlissingen, J M; Blankenstein, M A; Thijssen, J H; Colenbrander, B; Verbruggen, A J; Wensing, C J
1988-12-01
Sexual differentiation was investigated in familial male pseudohermaphroditism in Nyctereutes procyonoides (Canidae). In intersex males, development of external genital organs and prostate glandular tissue was severely disturbed; Wolffian (mesonephric) duct derivatives developed prepubertally but were absent in some adults. Müllerian (paramesonephric) duct regression was complete. Testicular descent was undisturbed. Male/female sex differences in plasma testosterone, 5 alpha-dihydrotestosterone, and luteinizing hormone concentrations were present. Intersex plasma hormone concentrations were within the normal male range. The concentration of androgen receptors in pubic skin was similar in male, female, and intersex animals and no significant differences in affinity for the ligand were detected. It was concluded that in intersex animals androgen-dependent virilisation was deficient despite the presence of androgens and androgen receptors and that this condition had not affected gubernaculum development and testicular descent.
Genetics Home Reference: androgen insensitivity syndrome
... particular ethnic groups? Genetic Changes Mutations in the AR gene cause androgen insensitivity syndrome . This gene provides ... hair growth and sex drive. Mutations in the AR gene prevent androgen receptors from working properly, which ...
DePriest, Adam D; Fiandalo, Michael V; Schlanger, Simon; Heemers, Frederike; Mohler, James L; Liu, Song; Heemers, Hannelore V
2016-01-01
Androgen receptor (AR) is a ligand-activated transcription factor that is the main target for treatment of non-organ-confined prostate cancer (CaP). Failure of life-prolonging AR-targeting androgen deprivation therapy is due to flexibility in steroidogenic pathways that control intracrine androgen levels and variability in the AR transcriptional output. Androgen biosynthesis enzymes, androgen transporters and AR-associated coregulators are attractive novel CaP treatment targets. These proteins, however, are characterized by multiple transcript variants and isoforms, are subject to genomic alterations, and are differentially expressed among CaPs. Determining their therapeutic potential requires evaluation of extensive, diverse datasets that are dispersed over multiple databases, websites and literature reports. Mining and integrating these datasets are cumbersome, time-consuming tasks and provide only snapshots of relevant information. To overcome this impediment to effective, efficient study of AR and potential drug targets, we developed the Regulators of Androgen Action Resource (RAAR), a non-redundant, curated and user-friendly searchable web interface. RAAR centralizes information on gene function, clinical relevance, and resources for 55 genes that encode proteins involved in biosynthesis, metabolism and transport of androgens and for 274 AR-associated coregulator genes. Data in RAAR are organized in two levels: (i) Information pertaining to production of androgens is contained in a 'pre-receptor level' database, and coregulator gene information is provided in a 'post-receptor level' database, and (ii) an 'other resources' database contains links to additional databases that are complementary to and useful to pursue further the information provided in RAAR. For each of its 329 entries, RAAR provides access to more than 20 well-curated publicly available databases, and thus, access to thousands of data points. Hyperlinks provide direct access to gene
The OECD has completed Phase-1 of the Hershberger validation intended to identify in vivo activity of
suspected androgens and antiandrogens. 17 laboratories from 7 countries participated in Phase-1, and results
were collated and evaluated by the OECD with the suppor...
Hamishehkar, Hamed; Ghanbarzadeh, Saeed; Sepehran, Sasan; Javadzadeh, Yousef; Adib, Zahra Mardhiah; Kouhsoltani, Maryam
2016-01-01
Flutamide is a potent anti-androgen with the several unwanted side effects in systemic administration, therefore, it has attracted special interest in the development of topically applied formulations for the treatment of androgenic alopecia. The purpose of this study was to prepare and characterize the solid lipid nanoparticles (SLNs) of Flutamide for follicular targeting in the treatment of the androgenic alopecia. Flutamide-loaded SLNs, promising drug carriers for topical application were prepared by hot melt homogenization method. Drug permeation and accumulation in the exercised rat skin and histological study on the male hamsters were performed to assess drug delivery efficiency in vitro and in vivo, respectively. The optimized Flutamide-loaded SLNs (size 198 nm, encapsulation efficiency percentage 65% and loading efficiency percentage 3.27%) exhibited a good stability during the period of at least 2 months. The results of X-ray diffraction showed Flutamide amorphous state confirming uniform drug dispersion in the SLNs structure. Higher skin drug deposition (1.75 times) of SLN formulation compared to Flutamide hydroalcoholic solution represented better localization of the drug in the skin. The in vivo studies showed more new hair follicle growth by utilizing Flutamide-loaded SLNs than Flutamide hydroalcoholic solution which could be due to the higher accumulation of SLNs in the hair follicles as well as slowly and continues release of the Flutamide through the SLNs maximizing hair follicle exposure by antiandrogenic drug. It was concluded Flutamide-loaded SLN formulation can be used as a promising colloidal drug carriers for topical administration of Flutamide in the treatment of androgenic alopecia.
Hypochlorite Oxidation of Select Androgenic Steroids
Steroid hormones are vital for regulation of various biological functions including sexual development. Elevated concentrations of natural and synthetic androgenic steroids have been shown to adversely affect normal development in indigenous aqueous species. Androgens and their s...
Kharlyngdoh, Joubert Banjop; Pradhan, Ajay; Asnake, Solomon; Walstad, Anders; Ivarsson, Per; Olsson, Per-Erik
2015-01-01
Brominated flame-retardants (BFRs) are used in industrial products to reduce the risk of fire. However, their continuous release into the environment is a concern as they are often persistent, bioaccumulating and toxic. Information on the impact these compounds have on human health and wildlife is limited and only a few of them have been identified to disrupt hormone receptor functions. In the present study we used in silico modeling to determine the interactions of selected BFRs with the human androgen receptor (AR). Three compounds were found to dock into the ligand-binding domain of the human AR and these were further tested using in vitro analysis. Allyl 2,4,6-tribromophenyl ether (ATE), 2-bromoallyl 2,4,6-tribromophenyl ether (BATE) and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE) were observed to act as AR antagonists. These BFRs have recently been detected in the environment, in house dust and in aquatic animals. The compounds have been detected at high concentrations in both blubber and brain of seals and we therefore also assessed their impact on the expression of L-type amino acid transporter system (LAT) genes, that are needed for amino acid uptake across the blood-brain barrier, as disruption of LAT gene function has been implicated in several brain disorders. The three BFRs down-regulated the expression of AR target genes that encode for prostate specific antigen (PSA), 5α-reductases and β-microseminoprotein. The potency of PSA inhibition was of the same magnitude as the common prostate cancer drugs, demonstrating that these compounds are strong AR antagonists. Western blot analysis of AR protein showed that ATE, BATE and DPTE decreased the 5α-dihydrotestosterone-induced AR protein levels, further confirming that these BFRs act as AR antagonists. The transcription of the LAT genes was altered by the three BFRs, indicating an effect on amino-acid uptake across cellular membranes and blood-brain barrier. This study demonstrated that ATE, BATE
Androgen actions on endothelium functions and cardiovascular diseases
Cai, Jing-Jing; Wen, Juan; Jiang, Wei-Hong; Lin, Jian; Hong, Yuan; Zhu, Yuan-Shan
2016-01-01
The roles of androgens on cardiovascular physiology and pathophysiology are controversial as both beneficial and detrimental effects have been reported. Although the reasons for this discrepancy are unclear, multiple factors such as genetic and epigenetic variation, sex-specificity, hormone interactions, drug preparation and route of administration may contribute. Recently, growing evidence suggests that androgens exhibit beneficial effects on cardiovascular function though the mechanism remains to be elucidated. Endothelial cells (ECs) which line the interior surface of blood vessels are distributed throughout the circulatory system, and play a crucial role in cardiovascular function. Endothelial progenitor cells (EPCs) are considered an indispensable element for the reconstitution and maintenance of an intact endothelial layer. Endothelial dysfunction is regarded as an initiating step in development of atherosclerosis and cardiovascular diseases. The modulation of endothelial functions by androgens through either genomic or nongenomic signal pathways is one possible mechanism by which androgens act on the cardiovascular system. Obtaining insight into the mechanisms by which androgens affect EC and EPC functions will allow us to determine whether androgens possess beneficial effects on the cardiovascular system. This in turn may be critical in the prevention and therapy of cardiovascular diseases. This article seeks to review recent progress in androgen regulation of endothelial function, the sex-specificity of androgen actions, and its clinical applications in the cardiovascular system. PMID:27168746
Effects of androgens on cardiovascular remodeling.
Ikeda, Yasumasa; Aihara, Ken-ichi; Yoshida, Sumiko; Akaike, Masashi; Matsumoto, Toshio
2012-07-01
Androgens, the male sex hormones, exert various biological effects on many target organs through the transcriptional effects of the nuclear androgen receptor (AR). ARs are expressed not only in classical target organs, such as the brain, genital organs, bone, and skeletal muscles, but also in the cardiovascular system. Because the female sex hormones estrogens are well-known to protect against cardiovascular disease, sex has been considered to have a significant clinical impact on cardiovascular mortality. However, the influence of androgens on the cardiovascular system has not been fully elucidated. To clarify this issue, we analyzed the effects of administration of angiotensin II and doxorubicin, an anticancer agent, in a loading model in male wild-type and AR-deficient mice. In this review, we focus on the actions of androgens as potential targets for the prevention of cardiovascular diseases in males.
Postmenopausal virilization after spousal use of topical androgens.
Merhi, Zaher O; Santoro, Nanette
2007-04-01
To increase awareness of the potential to cause virilization in postmenopausal woman secondary to a spouse's use of topical androgen. Case report. University-affiliated teaching hospital. A 63-year-old postmenopausal woman with virilization. Removal of the source of androgen exposure. Regression of the biochemical and physical signs of androgen excess in a woman after cessation of T gel use by her partner, and reinitiation of use with precautions against potential methods of transfer. This case highlights the unintentional transdermal absorption of testosterone sufficient to induce virilization in a couple who were aware of this potential problem. The apparent source of androgen absorption was a washcloth that the couple shared. The diagnosis can be established with a detailed history and a few blood tests (total and free T, and DHEAS) to exclude other sources of androgens. This report reinforces the need to consider exogenous androgen exposure in the differential diagnosis of virilization in adults when the more common causes have been excluded.
Davis, Susan R; Robinson, Penelope J; Moufarege, Alain; Bell, Robin J
2012-10-01
Sex hormone-binding globulin (SHBG) is a robust predictor of insulin resistance. Whether this is independent of circulating sex steroid levels remains uncertain. The aim of this study was to investigate the determinants of SHBG in postmenopausal women and whether the relationship between SHBG and insulin resistance is independent of oestrogen and androgen levels. A cross-sectional study of naturally and surgically menopausal women. Seven hundred and sixty three postmenopausal women not using any systemic hormone therapy, mean age 54·4 ± 5·8 years, recruited in the US, Canada, Australia, UK and Sweden between July 2004 and February 2005. Relationships between log-transformed (ln) SHBG and ln homoeostasis model assessment for insulin resistance (HOMA-IR) were explored, taking into account age, body mass index (BMI), blood pressure (BP) and circulating oestradiol, oestrone, testosterone and dihydrotestosterone. Taking into account age, race, years since menopause, menopause type, BMI, BP, prior postmenopausal hormone use and the sex steroids measured, 34·4% of the variation in SHBG could be explained by the model that included negative contributions by HOMA-IR, BMI and diastolic BP, and a positive contribution by total testosterone (P < 0·001). None of the sex steroids made independent contributions to HOMA-IR, which was best explained by the model that included BMI, SHBG, systolic BP and surgical menopause, with each variable being positively related to HOMA-IR (r(2) = 0·3152, P = 0·03). The relationship between SHBG and HOMA-IR, as an estimate of insulin resistance, is not explained by endogenous oestrogen and androgen levels and is, at least in part, independent of BMI in postmenopausal women. © 2011 Blackwell Publishing Ltd.
NASA Technical Reports Server (NTRS)
Schatten, H.; Ripple, M.; Balczon, R.; Weindruch, R.; Chakrabarti, A.; Taylor, M.; Hueser, C. N.
2000-01-01
We investigated the effects of androgen and taxol on the androgen-responsive LNCaP and androgen-independent DU145 prostate cancer cell lines. Cells were treated for 48 and 72 h with 0.05-1 nM of the synthetic androgen R1881 and with 100 nM taxol. Treatment of LNCaP cells with 0.05 nM R1881 led to increased cell proliferation, whereas treatment with 1 nM R1881 resulted in inhibited cell division, DNA cycle arrest, and altered centrosome organization. After treatment with 1 nM R1881, chromatin became clustered, nuclear envelopes convoluted, and mitochondria accumulated around the nucleus. Immunofluorescence microscopy with antibodies to centrosomes showed altered centrosome structure. Although centrosomes were closely associated with the nucleus in untreated cells, they dispersed into the cytoplasm after treatment with 1 nM R1881. Microtubules were only faintly detected in 1 nM R1881-treated LNCaP cells. The effects of taxol included microtubule bundling and altered mitochondria morphology, but not DNA organization. As expected, the androgen-independent prostate cancer cell line DU145 was not affected by R1881. Treatment with taxol resulted in bundling of microtubules in both cell lines. Additional taxol effects were seen in DU145 cells with micronucleation of DNA, an indication of apoptosis. Simultaneous treatment with R1881 and taxol had no additional effects on LNCaP or DU145 cells. These results suggest that LNCaP and DU145 prostate cancer cells show differences not only in androgen responsiveness but in sensitivity to taxol as well. Copyright 2000 Wiley-Liss, Inc.
Molecular profiles of finasteride effects on prostate carcinogenesis.
Li, Jin; Kim, Jeri
2009-06-01
Our inability to distinguish between low-grade prostate cancers that pose no threat and those that can kill compels newly diagnosed early prostate cancer patients to make decisions that may negatively affect their lives needlessly for years afterward. To reliably stratify patients into different risk categories and apply appropriate treatment, we need a better molecular understanding of prostate cancer progression. Androgen ablation therapy and 5-alpha reductase inhibitors reduce dihydrotestosterone levels and increase apoptosis. Because of the differing biological potentials of tumor cells, however, these treatments may, in some cases, worsen outcome by selecting for or inducing adaptation of stronger androgen receptor signaling pathways. Reduced dihydrotestosterone also may be associated with altered survival pathways. Complicating treatment effects further, molecular adaptation may be accelerated by interactions between epithelial and stromal cells. The hypothesis that early prostate cancer cells with differing biological potential may respond differently to finasteride treatment is worth testing. Ongoing studies using a systems biology approach in a preoperative prostate cancer setting are testing this hypothesis toward developing more-rational clinical interventions.
AB69. Phyto-androgenic androgens in men’s health, sex and aging FX
Adimoelja, Arif; Siauw, Ali Fuchih
2014-01-01
Protodioscin is a Herbal Steroid Saponin extract derived mainly from Tribulus terristris L. grown mainly in Bulgaria. This herbal plant begun well known in main stream medicine since the periods around 1972 in Indonesia when this phyto-steroid compound has been proven of having the ability to be converted to DHEA and further to another androgenic androgen (T) in hypogonadal men in the presence of 5-alpha-dehydrogenase (A. Adimoelja, 1976, 1978). Biogenic androgens and androgenic androgens Testosterone as a product of the male gonads from blood serum cholesterol. Cholesterol is further converted to DHEA. This product is identified as one of the biogenic or endogenic androgens (testosterone, pregnenolone, progesterone, aldosterone, androstendione). Health disorders are often hampered by the tendencies of men or women to conceal their health (sexual health) conditions due to fear and/or embarrassments. If these conditions are not being soonest medically diagnosed and left to be untreated, another un-healthy condition may appear. (hypertension, high blood serum cholesterol, decrease HDL, CVD). Decrease libido, sex arousal and ED are the first expression of the down-degraded health conditions which may appear (A. Adimoelja 1985). Prescription of phytopharmaceuticals in mainstream medicine Surprisingly more phyto-pharmaceuticals in mainstream medicine were unconsciously prescribed by physicians (25% of prescriptions, WHO, 1908). Prescriptions were made to support health conditions and promote sexual health problems, most common as aphrodisiacs. Prtodioscin and health enhancers Protodioscin indeed promote health condition in hypogonadic men (A.Adimoelja and Tjahjo Djojo Tanojo, 2009). Regretfully most herbal products whih has been promoted as health foods in the market, or sex-tonics are combined with other chemical product(s), some of which combined with erectogenics (W. Pangkahila, 2010). Sharlip ID (USA) too reported in the “Newark Star Ledger in 2002” that 9 out
Androgens as double-edged swords: Induction and suppression of follicular development.
Pan, Jie-Xue; Zhang, Jun-Yu; Ke, Zhang-Hong; Wang, Fang-Fang; Barry, John A; Hardiman, Paul J; Qu, Fan
2015-01-01
Androgens, which are mediated via the androgen receptor (AR), play important roles in normal follicular development and female fertility. However, just like a double-edged sword, besides the positive effects of androgen on follicular development, abnormal androgen levels, especially as in hyperandrogenism, seriously suppress normal follicular development. A crucial balance exists between the importance of androgens in follicular development and their negative effects when in excess. As the first meiotic division and epigenetic reprogramming are two critical events in oogenesis, abnormal androgen levels or deficiency in androgen/AR signaling in the ovary may affect these vital events. Oocytes have a tendency to develop genomic instability, thus resulting in an increasing incidence of unpredictable adult diseases. Although many studies have explored the effects of androgens and AR on follicular development, the conclusions are controversial and there has been no thorough review of this topic. This review focuses on the roles of androgens in the physiological process of follicular development, summarizes new insights into the roles of androgens in the arrested development of follicles, and discusses the potential risk of adult diseases originating from abnormal follicular androgen levels or androgen receptor signals, which may determine areas for future studies.
Zheng, Xi; Cui, Xiao-Xing; Huang, Mou-Tuan; Liu, Yue; Wagner, George C; Lin, Yong; Shih, Weichung Joe; Lee, Mao-Jung; Yang, Chung S; Conney, Allan H
2012-01-01
The effect of oral caffeine or voluntary running wheel exercise (RW) alone or in combination on the progression of human androgen-dependent LNCaP prostate tumors to androgen independence in male severe combined immunodeficiency mice was determined. The mice were injected subcutaneously with LNCaP cells, and when the tumors reached a moderate size, the mice were surgically castrated and treated with caffeine (0.40 mg/ml drinking water) or RW alone or in combination for 42 days. We found that caffeine administration or RW inhibited the progression and growth of androgen-dependent LNCaP tumors to androgen independence, and a combination of the 2 regimens was more effective than the individual regimens alone. The ratios of the percent mitotic cells/caspase-3 positive cells in tumors from the caffeine-treated, RW-treated, or combination-treated mice were decreased by 34%, 38%, and 52%, respectively. Caffeine treatment increased the percentage of mitotic tumor cells undergoing apoptosis (lethal mitosis) whereas RW inhibited the increase in interleukin-6 that occurred during the progression of LNCaP tumors from androgen dependence to androgen independence. Our results indicate that oral administration of caffeine in combination with voluntary exercise may be an effective strategy for the prevention of prostate cancer progression from androgen dependence to androgen independence.
Lin28 induces resistance to anti-androgens via promotion of AR splice variant generation.
Tummala, Ramakumar; Nadiminty, Nagalakshmi; Lou, Wei; Evans, Christopher P; Gao, Allen C
2016-04-01
Prostate cancer (PCa) is androgen-dependent initially and progresses to a castration-resistant state after androgen deprivation therapy. Treatment options for castration-resistant PCa include the potent second-generation anti-androgen enzalutamide or CYP17A1 inhibitor abiraterone. Recent clinical observations point to the development of resistance to these therapies which may be mediated by constitutively active alternative splice variants of the androgen receptor (AR). Sensitivity of LNCaP cells overexpressing Lin28 (LN-Lin28) to enzalutamide, abiraterone, or bicalutamide was compared to that of control LN-neo cells using cell growth assays, proliferation assays using MTT, anchorage-dependent clonogenic ability assays and soft agar assays. Ability of LN-Lin28 cells to maintain AR activation after treatment with enzalutamide, abiraterone, or bicalutamide was tested using immunofluorescence, Western blotting, ChIP assays, and qRT-PCR. Importance of Lin28 in enzalutamide resistance was assessed by the downregulation of Lin28 expression in C4-2B and 22Rv1 cells chronically treated with enzalutamide. Requirement for sustained AR signaling in LN-Lin28 cells was examined by the downregulation of either full length AR or AR-V7 using siRNA. We show that Lin28 promotes the development of resistance to currently used targeted therapeutics by enhancing the expression of AR splice variants such as AR-V7. PCa cells overexpressing Lin28 exhibit resistance to treatment with enzalutamide, abiraterone, or bicalutamide. Downregulation of Lin28 resensitizes enzalutamide-resistant PCa cells to enzalutamide treatment. We also show that the upregulation of splicing factors such as hnRNPA1 by Lin28 may mediate the enhanced generation of AR splice variants in Lin28-expressing cells. Our findings suggest that Lin28 plays a key role in the acquisition of resistance to AR-targeted therapies by PCa cells and establish the importance of Lin28 in PCa progression. © 2015 Wiley Periodicals, Inc.
Visualising Androgen Receptor Activity in Male and Female Mice
Dart, D. Alwyn; Waxman, Jonathan; Aboagye, Eric O.; Bevan, Charlotte L.
2013-01-01
Androgens, required for normal development and fertility of males and females, have vital roles in the reproductive tract, brain, cardiovascular system, smooth muscle and bone. Androgens function via the androgen receptor (AR), a ligand-dependent transcription factor. To assay and localise AR activity in vivo we generated the transgenic “ARE-Luc” mouse, expressing a luciferase reporter gene under the control of activated endogenous AR. In vivo imaging of androgen-mediated luciferase activity revealed several strongly expressing tissues in the male mouse as expected and also in certain female tissues. In males the testes, prostate, seminal vesicles and bone marrow all showed high AR activity. In females, strong activity was seen in the ovaries, uterus, omentum tissue and mammary glands. In both sexes AR expression and activity was also found in salivary glands, the eye (and associated glands), adipose tissue, spleen and, notably, regions of the brain. Luciferase protein expression was found in the same cell layers as androgen receptor expression. Additionally, mouse AR expression and activity correlated well with AR expression in human tissues. The anti-androgen bicalutamide reduced luciferase signal in all tissues. Our model demonstrates that androgens can act in these tissues directly via AR, rather than exclusively via androgen aromatisation to estrogens and activation of the estrogen receptor. Additionally, it visually demonstrates the fundamental importance of AR signalling outside the normal role in the reproductive organs. This model represents an important tool for physiological and developmental analysis of androgen signalling, and for characterization of known and novel androgenic or antiandrogenic compounds. PMID:23940781
Xie, Jinhan; Mølck, Christina; Paquet-Fifield, Sophie; Butler, Lisa; Sloan, Erica; Ventura, Sabatino; Hollande, Frédéric
2016-07-12
Progression of castration-resistant tumors is frequent in prostate cancer. Current systemic treatments for castration-resistant prostate cancer only produce modest increases in survival time and self-renewing Tumor-Initiating Cells (TICs) are suspected to play an important role in resistance to these treatments. However it remains unclear whether the same TICs display both chemo-resistance and self-renewing abilities throughout progression from early stage lesions to late, castration resistant tumors. Here, we found that treatment of mice bearing LNCaP-derived xenograft tumors with cytotoxic (docetaxel) and anti-androgen (flutamide) compounds enriched for cells that express TROP2, a putative TIC marker. Consistent with a tumor-initiating role, TROP2high cells from androgen-sensitive prostate cancer cell lines displayed an enhanced ability to re-grow in culture following treatment with taxane-based chemotherapy with or without androgen blockade. TROP2 down-regulation in these cells reduced their ability to recur after treatment with docetaxel, in the presence or absence of flutamide. Accordingly, in silico analysis of published clinical data revealed that prostate cancer patients with poor prognosis exhibit significantly elevated TROP2 expression level compared to low-risk patients, particularly in the case of patients diagnosed with early stage tumors. In contrast, in androgen-independent prostate cancer cell lines, TROP2high cells did not exhibit a differential treatment response but were characterized by their high self-renewal ability. Based on these findings we propose that high TROP2 expression identifies distinct cell sub-populations in androgen-sensitive and androgen-independent prostate tumors and that it may be a predictive biomarker for prostate cancer treatment response in androgen-sensitive tumors.
Circulating androgens in women: exercise-induced changes.
Enea, Carina; Boisseau, Nathalie; Fargeas-Gluck, Marie Agnès; Diaz, Véronique; Dugué, Benoit
2011-01-01
Physical exercise is known to strongly stimulate the endocrine system in both sexes. Among these hormones, androgens (e.g. testosterone, androstenedione, dehydroepiandrosterone) play key roles in the reproductive system, muscle growth and the prevention of bone loss. In female athletes, excessive physical exercise may lead to disorders, including delay in the onset of puberty, amenorrhoea and premature osteoporosis. The free and total fractions of circulating androgens vary in response to acute and chronic exercise/training (depending on the type), but the physiological role of these changes is not completely understood. Although it is commonly accepted that only the free fraction of steroids has a biological action, this hypothesis has recently been challenged. Indeed, a change in the total fraction of androgen concentration may have a significant impact on cells (inducing genomic or non-genomic signalling). The purpose of this review, therefore, is to visit the exercise-induced changes in androgen concentrations and emphasize their potential effects on female physiology. Despite some discrepancies in the published studies (generally due to differences in the types and intensities of the exercises studied, in the hormonal status of the group of women investigated and in the methods for androgen determination), exercise is globally able to induce an increase in circulating androgens. This can be observed after both resistance and endurance acute exercises. For chronic exercise/training, the picture is definitely less clear and there are even circumstances where exercise leads to a decrease of circulating androgens. We suggest that those changes have significant impact on female physiology and physical performance.
The androgen receptor gene mutations database.
Patterson, M N; Hughes, I A; Gottlieb, B; Pinsky, L
1994-09-01
The androgen receptor gene mutations database is a comprehensive listing of mutations published in journals and meetings proceedings. The majority of mutations are point mutations identified in patients with androgen insensitivity syndrome. Information is included regarding the phenotype, the nature and location of the mutations, as well as the effects of the mutations on the androgen binding activity of the receptor. The current version of the database contains 149 entries, of which 114 are unique mutations. The database is available from EMBL (NetServ@EMBL-Heidelberg.DE) or as a Macintosh Filemaker file (mc33001@musica.mcgill.ca).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Villagran, Marcelo A.; Gutierrez-Castro, Francisco A.; Pantoja, Diego F.
Prostate cancer (CaP) bone metastasis is an early event that remains inactive until later-stage progression. Reduced levels of circulating androgens, due to andropause or androgen deprivation therapies, alter androgen receptor (AR) coactivator expression. Coactivators shift the balance towards enhanced AR-mediated gene transcription that promotes progression to androgen-resistance. Disruptions in coregulators may represent a molecular switch that reactivates latent bone metastasis. Changes in AR-mediated transcription in androgen-sensitive LNCaP and androgen-resistant C4-2 cells were analyzed for AR coregulator recruitment in co-culture with Saos-2 and THP-1. The Saos-2 cell line derived from human osteosarcoma and THP-1 cell line representing human monocytes were usedmore » to display osteoblast and osteoclast activity. Increased AR activity in androgen-resistant C4-2 was due to increased AR expression and SRC1/TIF2 recruitment and decreased SMRT/NCoR expression. AR activity in both cell types was decreased over 90% when co-cultured with Saos-2 or THP-1 due to dissociation of AR from the SRC1/TIF2 and SMRT/NCoR coregulators complex, in a ligand-dependent and cell-type specific manner. In the absence of androgens, Saos-2 decreased while THP-1 increased proliferation of LNCaP cells. In contrast, both Saos-2 and THP-1 decreased proliferation of C4-2 in absence and presence of androgens. Global changes in gene expression from both CaP cell lines identified potential cell cycle and androgen regulated genes as mechanisms for changes in cell proliferation and AR-mediated transactivation in the context of bone marrow stroma cells. - Highlights: • Decreased corepressor expression change AR in androgen-resistance prostate cancer. • Bone stroma-derived cells change AR coregulator recruitment in prostate cancer. • Bone stroma cells change cell proliferation in androgen-resistant cancer cells. • Global gene expression in CaP cells is modified by bone stroma cells in
Characteristics of Men Who Report Persistent Sexual Symptoms After Finasteride Use for Hair Loss
Basaria, Shehzad; Jasuja, Ravi; Huang, Grace; Wharton, Whitney; Pan, Hong; Pencina, Karol; Li, Zhuoying; Travison, Thomas G.; Bhawan, Jag; Gonthier, Renaud; Labrie, Fernand; Dury, Alain Y.; Serra, Carlo; Papazian, Allen; O'Leary, Michael; Amr, Sami; Storer, Thomas W.; Stern, Emily
2016-01-01
Context: Some men who use finasteride for hair loss report persistent sexual and other symptoms after discontinuing finasteride therapy. Objective: To determine whether these persistent symptoms after discontinuation of finasteride use are due to androgen deficiency, decreased peripheral androgen action, or persistent inhibition of steroid 5α-reductase (SRD5A) enzymes. Participants: Finasteride users, who reported persistent sexual symptoms after discontinuing finasteride (group 1); age-matched finasteride users who did not report sexual symptoms (group 2); and healthy men who had never used finasteride (group 3). Outcomes: Sexual function, mood, affect, cognition, hormone levels, body composition, functional magnetic resonance imaging (fMRI) response to sexually and affectively valenced stimuli, nucleotide sequences of androgen receptor (AR), SRD5A1, and SRD5A2; expression levels of androgen-dependent genes in skin. Setting: Academic medical center. Results: Symptomatic finasteride users were similar in body composition, strength, and nucleotide sequences of AR, SRD5A1, and SRD5A2 genes to asymptomatic finasteride users and nonusers. Symptomatic finasteride users had impaired sexual function, higher depression scores, a more negative affectivity balance, and more cognitive complaints than men in groups 2 and 3 but had normal objectively assessed cognitive function. Testosterone, dihydrotestosterone, 5α-androstane-3α,17β-diol-glucuronide, testosterone to dihydrotestosterone and androsterone glucuronide to etiocholanolone glucuronide ratios, and markers of peripheral androgen action and expression levels of AR-dependent genes in skin did not differ among groups. fMRI blood oxygen level-dependent responses to erotic and nonerotic stimuli revealed abnormal function in brain circuitry linked to sexual arousal and major depression. Conclusions: We found no evidence of androgen deficiency, decreased peripheral androgen action, or persistent peripheral inhibition of
Wang, Xueni; Tao, Rui; Yang, Jing; Miao, Lin; Wang, Yu; Munyangaju, Jose Edouard; Wichai, Nuttapong; Wang, Hong; Zhu, Yan; Liu, Erwei; Chang, Yanxu; Gao, Xiumei
2017-01-01
To investigate the phytoestrogenic and phytoandrogenic activities of compounds isolated from CS and uncover the role of CS in prevention of oestrogen/androgen-induced BPH. Cells were treated with CS compounds, and immunofluorescence assay was performed to detect the nuclear translocation of ER α or AR in MCF-7 or LNCaP cells; luciferase reporter assay was performed to detect ERs or AR transcriptional activity in HeLa or AD293 cells; MTT assay was performed to detect the cell proliferation of MCF-7 or LNCaP cells. Oestrogen/androgen-induced BPH model was established in rat and the anti-BPH, anti-estrogenic, and anti-androgenic activities of CS in vivo were further investigated. The nuclear translocation of ER α was stimulated by nine CS compounds, three of which also stimulated AR translocation. The transcriptional activities of ER α and ER β were induced by five compounds, within which only ECG induced AR transcriptional activity as well. Besides, ECG stimulated the proliferation of both MCF-7 cells and LNCaP cells. CS extract suppressed oestrogen/androgen-induced BPH progress in vivo by downregulation of E2 and T level in serum and alteration of the expressions of ER α , ER β , and AR in the prostate. Our data demonstrates that compounds from CS exhibit phytoestrogenic and phytoandrogenic activities, which may contribute to inhibiting the oestrogen/androgen-induced BPH development.
Hormone Treatment and Muscle Anabolism during Aging: Androgens
Dillon, E. Lichar; Durham, William J.; Urban, Randall J.; Sheffield-Moore, Melinda
2010-01-01
Aging is associated with a gradual decline in circulating testosterone concentrations and decreased musculature in men. While testosterone administration is often considered when symptoms of hypogonadism are presented, the long-term effects of androgen use on muscle physiology are not yet fully understood. The definition of hypogonadism in men remains obscure but is generally indicated by total testosterone concentrations less than a threshold value of 300-500 ng/dL. Androgen replacement therapy is generally safe in men and women with low endogenous testosterone concentrations. The development of selective androgen receptor modulators (SARMs) may provide additional options in treatment of hypogonadism while lowering the potential of side effects often associated with long-term androgen use. Androgen administration, either alone or in combination with other treatments, can be successful in improving muscle mass by increasing protein anabolism and reducing protein catabolism in men and women. Further research is necessary to optimize the anabolic and anticatabolic properties of androgens for treatment and prevention of muscle loss in men and women. PMID:20452103
Rudzinskas, Sarah A.; Mong, Jessica A.
2015-01-01
Methamphetamine (MA) is a psychomotor stimulant associated with increases in sex drive in both men and women. Women, however, are far more likely to face social disadvantages as a consequence of MA use, and their increased sexual motivation poses additional health concerns such as unplanned pregnancies. To better understand the mechanisms underlying MA-facilitated sexual motivation in females, we previously established a rodent model where a ‘binge”-type administration paradigm of MA to sexually receptive female rats significantly increases proceptive behavior in the presence of a sexually active, gonadally-intact male. Our previous work with this model has led us to consider whether the increases in proceptive behavior are truly indicative of increased sexual motivation, or instead a consequence of heightened motor responsivity. Here, we test whether MA-induced increases in proceptive behaviors are specific to a sexually relevant stimulus. Females’ sexual, social, exploratory behaviors, and interaction times were scored during the exposure to stimulus males, including castrates, and dihydrotestosterone (DHT)-treated castrates. MA-treated females demonstrated significant increases in proceptive behaviors toward DHT-treated castrate males but not toward castrate males. While the non-MA-treated females did display proceptive behavior, there was no significant difference between behaviors elicited by DHT-CX males compared to CX males. Our results support the hypothesis that MA facilitates proceptive behavior only in response to specific, androgen mediated sexually-relevant cues. PMID:26497407
Illicit use of androgens and other hormones: recent advances.
Kanayama, Gen; Pope, Harrison G
2012-06-01
To summarize recent advances in studies of illicit use of androgens and other hormones. Androgens and other appearance-enhancing and performance-enhancing substances are widely abused worldwide. Three notable clusters of findings have emerged in this field in recent years. First, studies almost unanimously find that androgen users engage in polypharmacy, often ingesting other hormones (e.g., human growth hormone, thyroid hormones, and insulin), ergo/thermogenic drugs (e.g., caffeine, ephedrine, and clenbuterol), and classical drugs of abuse (e.g., cannabis, opiates, and cocaine). Second, reports of long-term psychiatric and medical adverse effects of androgens continue to accumulate. In cardiovascular research particularly, controlled studies have begun to supersede anecdotal evidence, strengthening the case that androgens (possibly acting synergistically with other abused drugs) may cause significant morbidity and even mortality. Third, it is increasingly recognized that androgen use may lead to a dependence syndrome with both psychological and physiological origins. Androgen dependence likely affects some millions of individuals worldwide, and arguably represents the least studied major class of illicit drug dependence. Given mounting evidence of the adverse effects of androgens and associated polypharmacy, this topic will likely represent an expanding area of research and an issue of growing public health concern.
Androgen associated hepatocellular carcinoma with an aggressive course.
Gleeson, D; Newbould, M J; Taylor, P; McMahon, R F; Leahy, B C; Warnes, T W
1991-01-01
The hepatocellular carcinomas that develop in patients treated with androgens have previously been associated with a benign clinical outcome. We describe a man who developed a hepatocellular carcinoma after 24 years of androgen treatment, whose tumour initially showed partial regression after withdrawal of androgens but subsequently pursued an aggressive and fatal course. Images Figure 1 Figure 2 PMID:1655591
Manire, C A; Rasmussen, L E; Gross, T S
1999-10-01
dihydrotestosterone concentrations increased. This study shows that although testosterone may be the primary androgen in the bonnethead shark, other derived androgens may have important functions in growth, maturation, and reproduction. J. Exp. Zool. 284:595-603, 1999. Copyright 1999 Wiley-Liss, Inc.
[Dihydrotestosterone improves the osseointegration of cobalt-chromium implants].
Maus, U M; Lühmann, M; Ohnsorge, J A K; Andereya, S; Schmidt, H; Zombory, G; Siebert, C; Niedhart, C
2013-02-01
The osseointegration of actually rarely implanted cobalt-chromium implants can be critical in an elderly population. The aim of our study was to evaluate the effect of preoperative testosterone treatment on the osseointegration of cobalt-chromium implants. Press-fit implantation of 1.6 mm-diameter cobalt-chromium-molybdenum (CoCrMo) implants was performed in rats without pre-treatment in one group (n = 10) and after pre-treatment with 1 mg dihydrotestosterone (DHT) 2 days before surgery in the other group (n = 10). After 14 days, the specimens were examined by a pull-out test, histology and histomorphometry. The biomechanical testing delivered inconsistent data leading to no significant difference (6.45 ± 6.94 N vs. 4.66 ± 3.77 N). Histology showed closed contact between surrounding tissue and the implants in both groups. The bone/implant contact area was significantly enhanced after treatment with DHT (42.23 % ± 9.25 vs. 57.57 % ± 16.71, p < 0.05), while the ratio of osteoid was reduced (38.68 % ± 16.7 vs. 27.38 % ± 13.02, not significant). Pre-treatment with DHT enhances osseointegration of cobalt-chromium implants through enhanced mineralisation of peri-implant tissue. The treatment might additionally shorten postoperative rehabilitation due to its positive effects on musculature. Georg Thieme Verlag KG Stuttgart · New York.
Androgen receptor-related diseases: what do we know?
Shukla, G C; Plaga, A R; Shankar, E; Gupta, S
2016-05-01
The androgen receptor (AR) and the androgen-AR signaling pathway play a significant role in male sexual differentiation and the development and function of male reproductive and non-reproductive organs. Because of AR's widely varied and important roles, its abnormalities have been identified in various diseases such as androgen insensitivity syndrome, spinal bulbar muscular atrophy, benign prostatic hyperplasia, and prostate cancer. This review provides an overview of the function of androgens and androgen-AR mediated diseases. In addition, the diseases delineated above are discussed with respect to their association with mutations and other post-transcriptional modifications in the AR. Finally, we present an introduction to the potential therapeutic application of most recent pharmaceuticals including miRNAs in prostate cancer that specifically target the transactivation function of the AR at post-transcriptional stages. © 2016 American Society of Andrology and European Academy of Andrology.
Lucas, Jared M.; Heinlein, Cynthia; Kim, Tom; Hernandez, Susana A.; Malik, Muzdah S.; True, Lawrence D.; Morrissey, Colm; Corey, Eva; Montgomery, Bruce; Mostaghel, Elahe; Clegg, Nigel; Coleman, Ilsa; Brown, Christopher M.; Schneider, Eric L.; Craik, Charles; Simon, Julian; Bedalov, Tony; Nelson, Peter S.
2014-01-01
TMPRSS2 is an androgen-regulated cell surface serine protease expressed predominantly in prostate epithelium. TMPRSS2 is expressed highly in localized high-grade prostate cancers and in the majority of human prostate cancer metastasis. Through the generation of mouse models with a targeted deletion of Tmprss2, we demonstrate that the activity of this protease regulates cancer cell invasion and metastasis to distant organs. By screening combinatorial peptide libraries we identified a spectrum of TMPRSS2 substrates that include pro-hepatocyte growth factor (HGF). HGF activated by TMPRSS2 promoted c-Met receptor tyrosine kinase signaling, and initiated a pro-invasive EMT phenotype. Chemical library screens identified a potent bioavailable TMPRSS2 inhibitor that suppressed prostate cancer metastasis in vivo. Together, these findings provide a mechanistic link between androgen-regulated signaling programs and prostate cancer metastasis that operate via context-dependent interactions with extracellular constituents of the tumor microenvironment. PMID:25122198
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hiort, O.; Huang, Q.; Sinnecker, G.H.G.
Recent studies indicate that mutations in the androgen receptor gene are associated with androgen insensitivity syndromes, a heterogeneous group of related disorders involving defective sexual differentiation in karyotypic males. In this report, the authors address the possibility of rapid mutational analysis of the androgen receptor gene for initial diagnosis, genetic counseling, and molecular subclassification of affected patients and their families. DNA from peripheral blood leukocytes of six patients from five families with various degrees of androgen insensitivity was studied. Exons 2 to 8 of the androgen receptor gene were analyzed using a combination of single strand conformation polymorphism analysis andmore » direct DNA sequencing. Female family members were also studied to identify heterozygote carriers. Point mutations in the AR gene were identified in all six patients, and all mutations caused amino acid substitutions. One patient with incomplete androgen insensitivity was a mosaic for the mutation. Four of the five mothers, as well as a young sister of one patient, were carriers of the mutation present in the affected child. The data show that new mutations may occur in the androgen receptor gene leading to sporadic androgen insensitivity syndrome. Molecular genetic characterization of the variant allele can serve as a primary tool for diagnosis and subsequent therapy, and can provide a basis for distinguishing heterozygous carriers in familial androgen resistance. The identification of carriers is of substantial clinical importance for genetic counseling. 29 refs., 2 figs., 1 tab.« less
Androgen replacement for women.
Basson, R.
1999-01-01
OBJECTIVES: To determine whether a postmenopausal syndrome comprising specific changes in sexual desire and response associated with low free testosterone exists. To determine whether this syndrome is ameliorated by testosterone replacement. QUALITY OF EVIDENCE: Literature documenting that replacement of physiological levels of testosterone is beneficial and safe is scant. Only one randomized prospective blinded study examines sexual outcome in detail. MAIN MESSAGE: Testosterone is an important metabolic and sex hormone produced by the ovary throughout life. The variable reduction in ovarian testosterone production coincident with menopause is sometimes associated with a syndrome of specific changes in sexual desire and sexual response. Estrogen deficiency also impairs sexual response, but its replacement will not improve and might exacerbate sexual symptoms from androgen loss. Diagnosis of androgen deficiency is clinical, based on accurate assessment of a woman's sexual status before and after menopause and only confirmed (rather than diagnosed) by a low level of free testosterone. Partial androgen replacement restores much of the sexual response and facilitates sexual desire that is triggered by external cues. Avoiding supraphysiological levels of testosterone lessens risk of masculinization. Avoiding alkylated testosterone lessens hepatic or lipid impairment. CONCLUSION: Further prospective randomized studies of replacement of physiological levels of testosterone in women with androgen deficiency syndrome are needed, using formulations of testosterone available in Canada. The consistency of sexual changes, the associated personal and relationship distress, together with our clinical experience of the gratifying response to physiological replacement, make further studies urgently needed. PMID:10509222
Badders, Nisha M; Korff, Ane; Miranda, Helen C; Vuppala, Pradeep K; Smith, Rebecca B; Winborn, Brett J; Quemin, Emmanuelle R; Sopher, Bryce L; Dearman, Jennifer; Messing, James; Kim, Nam Chul; Moore, Jennifer; Freibaum, Brian D; Kanagaraj, Anderson P; Fan, Baochang; Tillman, Heather; Chen, Ping-Chung; Wang, Yingzhe; Freeman, Burgess B; Li, Yimei; Kim, Hong Joo; La Spada, Albert R; Taylor, J Paul
2018-05-01
Spinal bulbar muscular atrophy (SBMA) is a motor neuron disease caused by toxic gain of function of the androgen receptor (AR). Previously, we found that co-regulator binding through the activation function-2 (AF2) domain of AR is essential for pathogenesis, suggesting that AF2 may be a potential drug target for selective modulation of toxic AR activity. We screened previously identified AF2 modulators for their ability to rescue toxicity in a Drosophila model of SBMA. We identified two compounds, tolfenamic acid (TA) and 1-[2-(4-methylphenoxy)ethyl]-2-[(2-phenoxyethyl)sulfanyl]-1H-benzimidazole (MEPB), as top candidates for rescuing lethality, locomotor function and neuromuscular junction defects in SBMA flies. Pharmacokinetic analyses in mice revealed a more favorable bioavailability and tissue retention of MEPB compared with TA in muscle, brain and spinal cord. In a preclinical trial in a new mouse model of SBMA, MEPB treatment yielded a dose-dependent rescue from loss of body weight, rotarod activity and grip strength. In addition, MEPB ameliorated neuronal loss, neurogenic atrophy and testicular atrophy, validating AF2 modulation as a potent androgen-sparing strategy for SBMA therapy.
Soper, Margaret S; Iganej, Shawn; Thompson, Lester D R
2014-01-01
Salivary duct carcinoma (SDC) is an aggressive malignancy with high recurrence rates. Standard management includes surgical resection followed by adjuvant radiation. Androgen receptor positivity has been described to be present in 40% to 90% of SDCs, and a recent case series showed a benefit to androgen deprivation therapy (ADT) in recurrent or metastatic disease. We present the case of an 87-year-old woman with a locally advanced androgen receptor-positive parotid SDC treated definitively with ADT and external beam radiotherapy, a regimen modeled after the treatment of prostate cancer. She had a complete response on positron emission tomography (PET)/CT scan and had no evidence of disease 24 months after the completion of treatment. To our knowledge, this case report is the first to describe the use of ADT plus radiation to definitively treat SDC. This regimen could be considered in patients with androgen receptor-positive SDCs who are considered unresectable or who refuse surgery. Copyright © 2013 Wiley Periodicals, Inc.
Discovery and therapeutic promise of selective androgen receptor modulators.
Chen, Jiyun; Kim, Juhyun; Dalton, James T
2005-06-01
Androgens are essential for male development and the maintenance of male secondary characteristics, such as bone mass, muscle mass, body composition, and spermatogenesis. The main disadvantages of steroidal androgens are their undesirable physicochemical and pharmacokinetic properties. The recent discovery of nonsteroidal selective androgen receptor modulators (SARMs) provides a promising alternative for testosterone replacement therapies with advantages including oral bioavailability, flexibility of structural modification, androgen receptor specificity, tissue selectivity, and the lack of steroid-related side effects.
Discovery AND Therapeutic Promise OF Selective Androgen Receptor Modulators
Chen, Jiyun; Kim, Juhyun; Dalton, James T.
2007-01-01
Androgens are essential for male development and the maintenance of male secondary characteristics, such as bone mass, muscle mass, body composition, and spermatogenesis. The main disadvantages of steroidal androgens are their undesirable physicochemical and pharmacokinetic properties. The recent discovery of nonsteroidal selective androgen receptor modulators (SARMs) provides a promising alternative for testosterone replacement therapies with advantages including oral bioavailability, flexibility of structural modification, androgen receptor specificity, tissue selectivity, and the lack of steroid-related side effects. PMID:15994457
Kojima, Hiroyuki; Katsura, Eiji; Takeuchi, Shinji; Niiyama, Kazuhito; Kobayashi, Kunihiko
2004-01-01
We tested 200 pesticides, including some of their isomers and metabolites, for agonism and antagonism to two human estrogen receptor (hER) subtypes, hERalpha and hERbeta, and a human androgen receptor (hAR) by highly sensitive transactivation assays using Chinese hamster ovary cells. The test compounds were classified into nine groups: organochlorines, diphenyl ethers, organophosphorus pesticides, pyrethroids, carbamates, acid amides, triazines, ureas, and others. These pesticides were tested at concentrations < 10-5 M. Of the 200 pesticides tested, 47 and 33 showed hER- and hERbeta-mediated estrogenic activities, respectively. Among them, 29 pesticides had both hERalpha and hERbeta agonistic activities, and the effects of the organochlorine insecticides beta-benzene hexachloride (BHC) and delta-BHC and the carbamate insecticide methiocarb were predominantly hERbeta rather than hERalpha agonistic. Weak antagonistic effects toward hERalpha and hERbeta were shown in five and two pesticides, respectively. On the other hand, none of tested pesticides showed hAR-mediated androgenic activity, but 66 of 200 pesticides exhibited inhibitory activity against the transcriptional activity induced by 5alpha-dihydrotestosterone. In particular, the antiandrogenic activities of two diphenyl ether herbicides, chlornitrofen and chlomethoxyfen, were higher than those of vinclozolin and p,p -dichlorodiphenyl dichloroethylene, known AR antagonists. The results of our ER and AR assays show that 34 pesticides possessed both estrogenic and antiandrogenic activities, indicating pleiotropic effects on hER and hAR. We also discussed chemical structures related to these activities. Taken together, our findings suggest that a variety of pesticides have estrogenic and/or antiandrogenic potential via ER and/or AR, and that numerous other manmade chemicals may also possess such estrogenic and antiandrogenic activities. PMID:15064155
Reduced bone mass and muscle strength in male 5α-reductase type 1 inactivated mice.
Windahl, Sara H; Andersson, Niklas; Börjesson, Anna E; Swanson, Charlotte; Svensson, Johan; Movérare-Skrtic, Sofia; Sjögren, Klara; Shao, Ruijin; Lagerquist, Marie K; Ohlsson, Claes
2011-01-01
Androgens are important regulators of bone mass but the relative importance of testosterone (T) versus dihydrotestosterone (DHT) for the activation of the androgen receptor (AR) in bone is unknown. 5α-reductase is responsible for the irreversible conversion of T to the more potent AR activator DHT. There are two well established isoenzymes of 5α-reductase (type 1 and type 2), encoded by separate genes (Srd5a1 and Srd5a2). 5α-reductase type 2 is predominantly expressed in male reproductive tissues whereas 5α-reductase type 1 is highly expressed in liver and moderately expressed in several other tissues including bone. The aim of the present study was to investigate the role of 5α-reductase type 1 for bone mass using Srd5a1⁻/⁻ mice. Four-month-old male Srd5a1⁻/⁻ mice had reduced trabecular bone mineral density (-36%, p<0.05) and cortical bone mineral content (-15%, p<0.05) but unchanged serum androgen levels compared with wild type (WT) mice. The cortical bone dimensions were reduced in the male Srd5a1⁻/⁻ mice as a result of a reduced cortical periosteal circumference compared with WT mice. T treatment increased the cortical periosteal circumference (p<0.05) in orchidectomized WT mice but not in orchidectomized Srd5a1⁻/⁻ mice. Male Srd5a1⁻/⁻ mice demonstrated a reduced forelimb muscle grip strength compared with WT mice (p<0.05). Female Srd5a1⁻/⁻ mice had slightly increased cortical bone mass associated with elevated circulating levels of androgens. In conclusion, 5α-reductase type 1 inactivated male mice have reduced bone mass and forelimb muscle grip strength and we propose that these effects are due to lack of 5α-reductase type 1 expression in bone and muscle. In contrast, the increased cortical bone mass in female Srd5a1⁻/⁻ mice, is an indirect effect mediated by elevated circulating androgen levels.
Reduced Bone Mass and Muscle Strength in Male 5α-Reductase Type 1 Inactivated Mice
Windahl, Sara H.; Andersson, Niklas; Börjesson, Anna E.; Swanson, Charlotte; Svensson, Johan; Movérare-Skrtic, Sofia; Sjögren, Klara; Shao, Ruijin; Lagerquist, Marie K.; Ohlsson, Claes
2011-01-01
Androgens are important regulators of bone mass but the relative importance of testosterone (T) versus dihydrotestosterone (DHT) for the activation of the androgen receptor (AR) in bone is unknown. 5α-reductase is responsible for the irreversible conversion of T to the more potent AR activator DHT. There are two well established isoenzymes of 5α-reductase (type 1 and type 2), encoded by separate genes (Srd5a1 and Srd5a2). 5α-reductase type 2 is predominantly expressed in male reproductive tissues whereas 5α-reductase type 1 is highly expressed in liver and moderately expressed in several other tissues including bone. The aim of the present study was to investigate the role of 5α-reductase type 1 for bone mass using Srd5a1−/− mice. Four-month-old male Srd5a1 −/− mice had reduced trabecular bone mineral density (−36%, p<0.05) and cortical bone mineral content (−15%, p<0.05) but unchanged serum androgen levels compared with wild type (WT) mice. The cortical bone dimensions were reduced in the male Srd5a1 −/− mice as a result of a reduced cortical periosteal circumference compared with WT mice. T treatment increased the cortical periosteal circumference (p<0.05) in orchidectomized WT mice but not in orchidectomized Srd5a1 −/− mice. Male Srd5a1 −/− mice demonstrated a reduced forelimb muscle grip strength compared with WT mice (p<0.05). Female Srd5a1 −/− mice had slightly increased cortical bone mass associated with elevated circulating levels of androgens. In conclusion, 5α-reductase type 1 inactivated male mice have reduced bone mass and forelimb muscle grip strength and we propose that these effects are due to lack of 5α-reductase type 1 expression in bone and muscle. In contrast, the increased cortical bone mass in female Srd5a1 −/− mice, is an indirect effect mediated by elevated circulating androgen levels. PMID:21731732
Rainbow Trout Androgen Receptor Alpha And Human Androgen Receptor: Comparisons in the COS Whole Cell Binding Assay
Mary C. Cardon, L. Earl Gray, Jr. and Vickie S. Wilson
U.S. Environmental Protection Agency, ORD, NHEERL, Reproductive Toxicology Division, Research Triangle...
Milutinović, Danijela Vojnović; Nikolić, Marina; Veličković, Nataša; Djordjevic, Ana; Bursać, Biljana; Nestorov, Jelena; Teofilović, Ana; Antić, Ivana Božić; Macut, Jelica Bjekić; Zidane, Abdulbaset Shirif; Matić, Gordana; Macut, Djuro
2017-09-01
Polycystic ovary syndrome is a heterogeneous endocrine and metabolic disorder associated with abdominal obesity, dyslipidemia and insulin resistance. Since abdominal obesity is characterized by low-grade inflammation, the aim of the study was to investigate whether visceral adipose tissue inflammation linked to abdominal obesity and dyslipidemia could lead to impaired insulin sensitivity in the animal model of polycystic ovary syndrome.Female Wistar rats were treated with nonaromatizable 5α-dihydrotestosterone pellets in order to induce reproductive and metabolic characteristics of polycystic ovary syndrome. Glucose, triglycerides, non-esterified fatty acids and insulin were determined in blood plasma. Visceral adipose tissue inflammation was evaluated by the nuclear factor kappa B intracellular distribution, macrophage migration inhibitory factor protein level, as well as TNFα, IL6 and IL1β mRNA levels. Insulin sensitivity was assessed by intraperitoneal glucose tolerance test and homeostasis model assessment index, and through analysis of insulin signaling pathway in the visceral adipose tissue.Dihydrotestosterone treatment led to increased body weight, abdominal obesity and elevated triglycerides and non-esterified fatty acids, which were accompanied by the activation of nuclear factor kappa B and increase in macrophage migration inhibitory factor, IL6 and IL1β levels in the visceral adipose tissue. In parallel, insulin sensitivity was affected in 5α-dihydrotestosterone-treated animals only at the systemic and not at the level of visceral adipose tissue.The results showed that abdominal obesity and dyslipidemia in the animal model of polycystic ovary syndrome were accompanied with low-grade inflammation in the visceral adipose tissue. However, these metabolic disturbances did not result in decreased tissue insulin sensitivity. © Georg Thieme Verlag KG Stuttgart · New York.
Selective Androgen Receptor Downregulators (SARDs): A New Prostate Cancer Therapy
2006-10-01
of the androgen receptor messenger RNA and functional inhibition of androgen receptor activity by a hammerhead ribozyme . Mol Endocrinol, 12: 1558...cleavage of the androgen receptor messenger RNA and functional inhibition of androgen receptor activity by a hammerhead ribozyme . Mol Endocrinol...used to down-regulate the AR include antisense oligonucleotides (9, 10), ribozyme treatments (11, 12), AR dominant negatives (13) and small
Evolution of the androgen-induced male phenotype.
Fuxjager, Matthew J; Miles, Meredith C; Schlinger, Barney A
2018-01-01
The masculine reproductive phenotype varies significantly across vertebrates. As a result, biologists have long recognized that many of the mechanisms that support these phenotypes-particularly the androgenic system-is evolutionarily labile, and thus susceptible to the effects of selection for different traits. However, exactly how androgenic signaling systems vary in a way which results in dramatically different functional outputs, remain largely unclear. We explore this topic here by outlining four key-but non-mutually exclusive-hypotheses that propose how the mechanisms of androgenic signaling might change over time to potentiate the emergence of phenotypical variation in masculine behavior and physiology. We anchor this framework in a review of our own studies of a tropical bird called the golden-collared manakin (Manacus vitellinus), which has evolved an exaggerated acrobatic courtship display that is heavily androgen-dependent. The result is an example of how the cellular basis of androgenic action can be modified to support a unique reproductive repertoire. We end this review by highlighting a broad pathway forward to further pursue the intricate ways by which the mechanisms of hormone action evolve to support processes of adaptation and animal design.
Kim, Seung-Jin; Choi, Hojung; Park, Sung-Soo; Chang, Chawnshang; Kim, Eungseok
2011-01-01
Stearoyl-CoA desaturase (SCD), the rate-limiting enzyme in the biosynthesis of monounsaturated fatty acids, is highly expressed in prostate cancer although the SCD protein has been known to be rapidly turned over by proteolytic cleavage. The present data demonstrate that SCD can promote proliferation of androgen receptor (AR)-positive LNCaP prostate cancer cells and enhance dihydrotestosterone (DHT)-induced AR transcriptional activity, resulting in increased expression of prostatespecific antigen (PSA) and kallikrein-related peptidase 2 (KLK2). Interestingly, among the previously reported SCDderived peptides produced by proteolytic cleavage of SCD, a peptide spanning amino acids 130-162 of SCD (SCDCoRNR) contained the CoRNR box motif (LFLII) and enhanced AR transcriptional activity. In contrast, a mutant SCD-CoRNR in which Leu136 was replaced by Ala had no effect on AR transcriptional activity. Moreover, SCDCoRNR directly interacted with AR and inhibited RIP140 suppression of AR transactivation. Knockdown of the SCD gene by SCD microRNA suppressed AR transactivation with decreased cell proliferation, suggesting that SCD may regulate the proliferation of LNCaP cells via modulation of AR transcriptional activity. Moreover, ectopic expression of SCD in LNCaP cells facilitated LNCaP tumor formation and growth in nude mice. Together, the data indicate that SCD plays a key role in the regulation of AR transcriptional activity in prostate cancer cells. PMID:21331774
RAINBOW TROUT ANDROGEN RECEPTOR ALPHA AND HUMAN ANDROGEN RECEPTOR: COMPARISONS IN THE COS WHOLE CELL BINDING ASSAY.
MC Cardon, PC Hartig,LE Gray, Jr. and VS Wilson.
U.S. EPA, ORD, NHEERL, RTD, Research Triangle Park, NC, USA.
Typically, in vitro hazard assessments for ...
Hamdi, M M; Mutungi, G
2011-01-01
Abstract Dihydrotestosterone (DHT) has acute/non-genomic actions in adult mammalian skeletal muscles whose physiological functions are still poorly understood. Therefore, the primary aim of this study was to investigate the acute/non-genomic effects of DHT on amino acid uptake as well as the cellular signal transduction events underlying these actions in mouse fast- and slow-twitch skeletal muscle fibre bundles. 14C-Labelled amino acids were used to investigate the effects of DHT and testosterone (T) on amino acid uptake and pharmacological interventions were used to determine the cellular signal transduction events mediating these actions. While T had no effect on the uptake of isoleucine (Ile) and α-methylaminoisobutyric acid (MeAIB) in both fibre types, DHT increased their uptake in the fast-twitch fibre bundles. This effect was reversed by inhibitors of protein translation, the epidermal growth factor receptor (EGFR), system A, system L, mTOR and MEK. However, it was relatively insensitive to inhibitors of transcription, androgen receptors and PI3K/Akt. Additionally, DHT treatment increased the expression of LAT2 and the phosphorylation of the EGFR in the fast-twitch fibre bundles and that of ERK1/2, RSK1/2 and ATF2 in both fibre types. Also, it decreased the phosphorylation of eEF2 and increased the incorporation of Ile into proteins in both fibre types. Most of these effects were reversed by EGFR and MEK inhibitors. From these findings we suggest that another physiological function of the acute/non-genomic actions of DHT in isolated mammalian skeletal muscle fibres is to stimulate amino acid uptake. This effect is mediated through the EGFR and involves the activation of the MAPK pathway and an increase in LAT2 expression. PMID:21606113
Prall, Sean P; Ambu, Laurentius; Nathan, Senthilvel; Alsisto, Sylvia; Ramirez, Diana; Muehlenbein, Michael P
2015-06-01
Despite the implications for the development of life-history traits, endocrine-immune trade-offs in apes are not well studied. This is due, in part, to difficulty in sampling wild primates, and lack of methods available for immune measures using samples collected noninvasively. Evidence for androgen-mediated immune trade-offs in orangutans is virtually absent, and very little is known regarding their pattern of adrenal development and production of adrenal androgens. To remedy both of these deficiencies, sera were collected from orangutans (Pongo pygmaeus morio) (N = 38) at the Sepilok Orangutan Rehabilitation Centre, Sabah, Malaysia, during routine health screenings. Testosterone, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone-sulfate (DHEA-S) were assayed, along with two measures of functional innate immunity. DHEA-S concentrations, but not DHEA, increased with age in this sample of 1-18 year old animals. DHEA concentrations were higher in animals with higher levels of serum bacteria killing ability, while DHEA-S and testosterone concentrations were higher in animals with reduced complement protein activity. Patterns of DHEA-S concentration in this sample are consistent with patterns of adrenarche observed in other apes. Results from this study suggest that in addition to testosterone, DHEA and DHEA-S may have potent effects on immunological activity in this species. © 2015 Wiley Periodicals, Inc.
Differential Mechanisms of Androgen Resistance
2005-12-01
and 20 ng CMV– renilla vector which was used as a transfection control. Two contrasting target reporter genes were utilised; a simple promoter...for 24 hrs prior to transfection with 4 ng human androgen receptor and 20 ng renilla as a transfection control. Two reporters were utilised 200 ng...androgen specific reporter (C’∆9 tkta Luciferase, 1μg and CMV- Renilla , 10 ng as transfection control). Twenty-four hours after transfection cells were
Androgen excess: Investigations and management.
Lizneva, Daria; Gavrilova-Jordan, Larisa; Walker, Walidah; Azziz, Ricardo
2016-11-01
Androgen excess (AE) is a key feature of polycystic ovary syndrome (PCOS) and results in, or contributes to, the clinical phenotype of these patients. Although AE will contribute to the ovulatory and menstrual dysfunction of these patients, the most recognizable sign of AE includes hirsutism, acne, and androgenic alopecia or female pattern hair loss (FPHL). Evaluation includes not only scoring facial and body terminal hair growth using the modified Ferriman-Gallwey method but also recording and possibly scoring acne and alopecia. Moreover, assessment of biochemical hyperandrogenism is necessary, particularly in patients with unclear or absent hirsutism, and will include assessing total and free testosterone (T), and possibly dehydroepiandrosterone sulfate (DHEAS) and androstenedione, although these latter contribute limitedly to the diagnosis. Assessment of T requires use of the highest quality assays available, generally radioimmunoassays with extraction and chromatography or mass spectrometry preceded by liquid or gas chromatography. Management of clinical hyperandrogenism involves primarily either androgen suppression, with a hormonal combination contraceptive, or androgen blockade, as with an androgen receptor blocker or a 5α-reductase inhibitor, or a combination of the two. Medical treatment should be combined with cosmetic treatment including topical eflornithine hydrochloride and short-term (shaving, chemical depilation, plucking, threading, waxing, and bleaching) and long-term (electrolysis, laser therapy, and intense pulse light therapy) cosmetic treatments. Generally, acne responds to therapy relatively rapidly, whereas hirsutism is slower to respond, with improvements observed as early as 3 months, but routinely only after 6 or 8 months of therapy. Finally, FPHL is the slowest to respond to therapy, if it will at all, and it may take 12 to 18 months of therapy for an observable response. Copyright © 2016. Published by Elsevier Ltd.
Price, Douglas K.; Chau, Cindy H.; Till, Cathee; Goodman, Phyllis J.; Leach, Robin J.; Johnson-Pais, Teresa L.; Hsing, Ann W.; Hoque, Ashraful; Parnes, Howard L.; Schenk, Jeannette M.; Tangen, Catherine M.; Thompson, Ian M.; Reichardt, Juergen K.V.; Figg, William D.
2016-01-01
Background Prostate cancer is highly influenced by androgens and genes. We investigated whether genetic polymorphisms along the androgen biosynthesis and metabolism pathways are associated with androgen concentrations or risk of prostate cancer or high-grade disease from finasteride treatment. Methods A nested case-control study from the Prostate Cancer Prevention Trial using cases drawn from men with biopsy-proven prostate cancer and biopsy-negative, frequency-matched controls was conducted to investigate the association of 51 single nucleotide polymorphisms (SNPs) in 12 genes of the androgen pathway with total, low-grade, and high-grade prostate cancer incidence and serum hormone concentrations. Results There were significant associations of genetic polymorphisms in SRD5A1 (rs3736316, rs3822430, rs1560149, rs248797, and rs472402) and SRD5A2 (rs2300700) with risk of high-grade prostate cancer in the placebo arm of the PCPT; two SNPs were significantly associated with increased risk (SRD5A1 rs472402 [OR, 1.70; 95% CI, 1.05-2.75, Ptrend=0.03]; SRD5A2 rs2300700 [OR, 1.94; 95% CI, 1.19-3.18, Ptrend=0.01]). Eleven SNPs in SRD5A1, SRD5A2, CYP1B1, and CYP3A4 were found to be associated with modifying mean serum androgen and sex hormone-binding globulin concentrations; two SNPs (SRD5A1 rs824811 and CYP1B1 rs10012, Ptrend<0.05) consistently and significantly altered all androgen concentrations. Several SNPs (rs3822430, rs2300700; CYP3A43 rs800672; CYP19 rs700519; Ptrend<0.05) were significantly associated with both circulating hormone levels and prostate cancer risk. Conclusion Germline genetic variations of androgen-related pathway genes are associated with serum androgen concentrations and risk of prostate cancer. Further studies to examine the functional consequence of novel causal variants are warranted. PMID:27164191
Dissecting the roles of the androgen receptor in prostate cancer from molecular perspectives.
Hu, Jieping; Wang, Gongxian; Sun, Ting
2017-05-01
Androgen receptor plays a pivotal role in prostate cancer progression, and androgen deprivation therapy to intercept androgen receptor signal pathway is an indispensable treatment for most advanced prostate cancer patients to delay cancer progression. However, the emerging of castration-resistant prostate cancer reminds us the alteration of androgen receptor, which includes androgen receptor mutation, the formation of androgen receptor variants, and androgen receptor distribution in cancer cells. In this review, we introduce the process of androgen receptor and also its variants' formation, translocation, and function alteration by protein modification or interaction with other pathways. We dissect the roles of androgen receptor in prostate cancer from molecular perspective to provide clues for battling prostate cancer, especially castration-resistant prostate cancer.
Emotional Consequences of Finasteride: Fool’s Gold
Ganzer, Christine Anne; Jacobs, Alan Roy
2016-01-01
Androgenetic alopecia, the gradual, progressive loss of hair frequently results in psychological despair, in part related to changes in self-image. Current androgenetic alopecia treatments are limited to hair transplantation and medications that inhibit dihydrotestosterone, a potent androgen associated with follicular micronization. Users of finasteride, which prevents dihydrotestosterone production, report serious physical and emotional adverse effects, collectively known as post-finasteride syndrome. Psychiatric illnesses and personality traits, specifically neuroticism influence emotional well-being. Limited research exists exploring the psychological corollaries of post-finasteride syndrome and preexisting Axis I and Axis II mental health conditions. The aim of this study was to explore how having a preexisting personal and/or familial history of a psychiatric diagnosis and certain personality traits may influence anxiety and depression among finasteride users. Participants in this online survey completed the Beck Depression Inventory, the Beck Anxiety Inventory, and Ten-Item Personality Inventory. An important finding in this study was that almost 57% (n = 97) of men reported a psychiatric diagnosis and 28% (n = 27) had a first-degree relative with a mental health disorder, of this group 17 only had a family history. Nearly 50% of the men surveyed reported clinically significant depression as evidenced by Beck Depression Inventory score and 34% experienced anxiety on the Beck Anxiety Inventory. There were no statistically significant trends in personality traits reported. Results provide evidence on the need to screen for psychiatric history and counseling patients about the potential psychological consequences of finasteride. Prescribing clinicians should carefully weigh the risk/benefit ratio with these patients. PMID:26868914
Ryan, Calen P; Georgiev, Alexander V; McDade, Thomas W; Gettler, Lee T; Eisenberg, Dan T A; Rzhetskaya, Margarita; Agustin, Sonny S; Hayes, M Geoffrey; Kuzawa, Christopher W
2017-06-01
The androgen receptor (AR) mediates expression of androgen-associated somatic traits such as muscle mass and strength. Within the human AR is a highly variable glutamine short-tandem repeat (AR-CAGn), and CAG repeat number has been inversely correlated to AR transcriptional activity in vitro. However, evidence for an attenuating effect of long AR-CAGn on androgen-associated somatic traits has been inconsistent in human populations. One possible explanation for this lack of consistency is that the effect of AR-CAGn on AR bioactivity in target tissues likely varies in relation to circulating androgen levels. We tested whether relationships between AR-CAGn and several androgen-associated somatic traits (waist circumference, lean mass, arm muscle area, and grip strength) were modified by salivary (waking and pre-bed) and circulating (total) testosterone (T) levels in young adult males living in metropolitan Cebu, Philippines (n = 675). When men's waking T was low, they had a reduction in three out of four androgen-associated somatic traits with lengthening AR-CAGn (p < .1), consistent with in vitro research. However, when waking T was high, we observed the opposite effect-lengthening AR-CAGn was associated with an increase in these same somatic traits. Our finding that longer AR-CAGn predicts greater androgen-associated trait expression among high-T men runs counter to in vitro work, but is generally consistent with the few prior studies to evaluate similar interactions in human populations. Collectively, these results raise questions about the applicability of findings derived from in vitro AR-CAGn studies to the receptor's role in maintaining androgen-associated somatic traits in human populations. © 2017 Wiley Periodicals, Inc.
The androgen receptor gene mutations database.
Gottlieb, B; Trifiro, M; Lumbroso, R; Pinsky, L
1997-01-01
The current version of the androgen receptor (AR) gene mutations database is described. The total number of reported mutations has risen from 212 to 272. We have expanded the database: (i) by adding a large amount of new data on somatic mutations in prostatic cancer tissue; (ii) by defining a new constitutional phenotype, mild androgen insensitivity (MAI); (iii) by placing additional relevant information on an internet site (http://www.mcgill.ca/androgendb/ ). The database has allowed us to examine the contribution of CpG sites to the multiplicity of reports of the same mutation in different families. The database is also available from EMBL (ftp.ebi.ac.uk/pub/databases/androgen) or as a Macintosh Filemaker Pro or Word file (MC33@musica,mcgill.ca)
The androgen receptor gene mutations database.
Gottlieb, B; Trifiro, M; Lumbroso, R; Pinsky, L
1997-01-01
The current version of the androgen receptor (AR) gene mutations database is described. The total number of reported mutations has risen from 212 to 272. We have expanded the database: (i) by adding a large amount of new data on somatic mutations in prostatic cancer tissue; (ii) by defining a new constitutional phenotype, mild androgen insensitivity (MAI); (iii) by placing additional relevant information on an internet site (http://www.mcgill.ca/androgendb/ ). The database has allowed us to examine the contribution of CpG sites to the multiplicity of reports of the same mutation in different families. The database is also available from EMBL (ftp.ebi.ac.uk/pub/databases/androgen) or as a Macintosh Filemaker Pro or Word file (MC33@musica,mcgill.ca) PMID:9016528
Escobar-Morreale, Héctor F
2017-01-01
Polycystic ovary syndrome (PCOS) is characterized by the association of androgen excess with chronic oligoovulation and/or polycystic ovarian morphology, yet metabolic disorders and classic and nonclassic cardiovascular risk factors cluster in these women from very early in life. This chapter focuses on the mechanisms underlying the association of PCOS with metabolic dysfunction, focusing on the role of androgen excess on the development of visceral adiposity and adipose tissue dysfunction.
Palethorpe, Helen M; Leach, Damien A; Need, Eleanor F; Drew, Paul A; Smith, Eric
2018-04-10
Fibroblasts express androgen receptor (AR) in the normal prostate and during prostate cancer development. We have reported that loss of AR expression in prostate cancer-associated fibroblasts is a poor prognostic indicator. Here we report outcomes of direct and indirect co-cultures of immortalised AR-positive (PShTert-AR) or AR-negative (PShTert) myofibroblasts with prostate cancer cells. In the initial co-cultures the AR-negative PC3 cell line was used so AR expression and signalling were restricted to the myofibroblasts. In both direct and indirect co-culture with PShTert-AR myofibroblasts, paracrine signalling to the PC3 cells slowed proliferation and induced apoptosis. In contrast, PC3 cells proliferated with PShTert myofibroblasts irrespective of the co-culture method. In direct co-culture PC3 cells induced apoptosis in and destroyed PShTerts by direct signalling. Similar results were seen in direct co-cultures with AR-negative DU145 and AR-positive LNCaP and C4-2B prostate cancer cell lines. The AR ligand 5α-dihydrotestosterone (DHT) inhibited the proliferation of the PShTert-AR myofibroblasts, thereby reducing the extent of their inhibitory effect on cancer cell growth. These results suggest loss of stromal AR would favour prostate cancer cell growth in vivo , providing an explanation for the clinical observation that reduced stromal AR is associated with a poorer outcome.
Palethorpe, Helen M.; Leach, Damien A.; Need, Eleanor F.; Drew, Paul A.; Smith, Eric
2018-01-01
Fibroblasts express androgen receptor (AR) in the normal prostate and during prostate cancer development. We have reported that loss of AR expression in prostate cancer-associated fibroblasts is a poor prognostic indicator. Here we report outcomes of direct and indirect co-cultures of immortalised AR-positive (PShTert-AR) or AR-negative (PShTert) myofibroblasts with prostate cancer cells. In the initial co-cultures the AR-negative PC3 cell line was used so AR expression and signalling were restricted to the myofibroblasts. In both direct and indirect co-culture with PShTert-AR myofibroblasts, paracrine signalling to the PC3 cells slowed proliferation and induced apoptosis. In contrast, PC3 cells proliferated with PShTert myofibroblasts irrespective of the co-culture method. In direct co-culture PC3 cells induced apoptosis in and destroyed PShTerts by direct signalling. Similar results were seen in direct co-cultures with AR-negative DU145 and AR-positive LNCaP and C4-2B prostate cancer cell lines. The AR ligand 5α-dihydrotestosterone (DHT) inhibited the proliferation of the PShTert-AR myofibroblasts, thereby reducing the extent of their inhibitory effect on cancer cell growth. These results suggest loss of stromal AR would favour prostate cancer cell growth in vivo, providing an explanation for the clinical observation that reduced stromal AR is associated with a poorer outcome. PMID:29721186
Ogino, Yukiko; Hirakawa, Ikumi; Inohaya, Keiji; Sumiya, Eri; Miyagawa, Shinichi; Denslow, Nancy; Yamada, Gen; Tatarazako, Norihisa; Iguchi, Taisen
2014-02-01
Androgens play key roles in the morphological specification of male type sex attractive and reproductive organs, whereas little is known about the developmental mechanisms of such secondary sex characters. Medaka offers a clue about sexual differentiation. They show a prominent masculine sexual character for appendage development, the formation of papillary processes in the anal fin, which has been induced in females by exogenous androgen exposure. This current study shows that the development of papillary processes is promoted by androgen-dependent augmentation of bone morphogenic protein 7 (Bmp7) and lymphoid enhancer-binding factor-1 (Lef1). Androgen receptor (AR) subtypes, ARα and ARβ, are expressed in the distal region of outgrowing bone nodules of developing papillary processes. Development of papillary processes concomitant with the induction of Bmp7 and Lef1 in the distal bone nodules by exposure to methyltestosterone was significantly suppressed by an antiandrogen, flutamide, in female medaka. When Bmp signaling was inhibited in methyltestosterone-exposed females by its inhibitor, dorsomorphin, Lef1 expression was suppressed accompanied by reduced proliferation in the distal bone nodules and retarded bone deposition. These observations indicate that androgen-dependent expressions of Bmp7 and Lef1 are required for the bone nodule outgrowth leading to the formation of these secondary sex characteristics in medaka. The formation of androgen-induced papillary processes may provide insights into the mechanisms regulating the specification of sexual features in vertebrates.
Diethylstilbesterol revisited: androgen deprivation, osteoporosis and prostate cancer.
Scherr, Douglas; Pitts, W Reid; Vaughn, E Darracott
2002-02-01
It is well described in the urological literature that androgen deprivation can result in accelerated bone breakdown and osteoporosis. Therefore, we evaluate the degree of bone breakdown in patients on conventional androgen deprivation with those on diethylstilbesterol alone or in conjunction with luteinizing hormone releasing hormone agonists or orchiectomy. During an 18-month period a total of 54 patients with clinically localized prostate cancer and 24 with benign prostatic hyperplasia were evaluated. All patients with prostate cancer were either treated with external beam radiotherapy without androgen deprivation or were started on androgen deprivation therapy. All patients were prospectively followed and evaluated for serum testosterone and estradiol along with urinary collagen type I cross-linked N-telopeptides. Three separate morning urine samples on 3 separate months were collected on each patient and analyzed for N-telopeptides. To correct for different levels of renal function, all N-telopeptides were measured as a ratio of urinary N-telopeptides/urine creatinine. All patients with any bone or skeletal abnormalities were excluded from study as were those with osseous metastatic disease. There was a statistically significant (p < 0.05) higher level of urinary N-telopeptides/creatinine in patients on androgen deprivation therapy who were not treated with diethylstilbesterol. The estrogenic effect of diethylstilbesterol protects one from bone resorption. Patients on diethylstilbesterol did not have any higher levels of bone breakdown than patients with benign prostatic hyperplasia or those who never received any androgen deprivation. Rapid bone turnover and resorption can be prevented with 1 mg. diethylstilbesterol alone or in conjunction with other modes of androgen deprivation. Therefore, diethylstilbesterol should be considered as monotherpy in men who require long-term antiandrogen therapy.
Yu, I-Chen; Lin, Hung-Yun; Sparks, Janet D.; Yeh, Shuyuan
2014-01-01
Prostate cancer (PCa) is one of the most frequently diagnosed malignancies in men. Androgen-deprivation therapy (ADT) is the first-line treatment and fundamental management for men with advanced PCa to suppress functions of androgen/androgen receptor (AR) signaling. ADT is effective at improving cancer symptoms and prolonging survival. However, epidemiological and clinical studies support the notion that testosterone deficiency in men leads to the development of metabolic syndrome that increases cardiovascular disease risk. The underlying mechanisms by which androgen/AR signaling regulates metabolic homeostasis in men are complex, and in this review, we discuss molecular mechanisms mediated by AR signaling that link ADT to metabolic syndrome. Results derived from various AR knockout mouse models reveal tissue-specific AR signaling that is involved in regulation of metabolism. These data suggest that steps be taken early to manage metabolic complications associated with PCa patients receiving ADT, which could be accomplished using tissue-selective modulation of AR signaling and by treatment with insulin-sensitizing agents. PMID:25249645
A preliminary MTD-PLS study for androgen receptor binding of steroid compounds
NASA Astrophysics Data System (ADS)
Bora, Alina; Seclaman, E.; Kurunczi, L.; Funar-Timofei, Simona
The relative binding affinities (RBA) of a series of 30 steroids for Human Androgen Receptor (AR) were used to initiate a MTD-PLS study. The 3D structures of all the compounds were obtained through geometry optimization in the framework of AM1 semiempirical quantum chemical method. The MTD hypermolecule (HM) was constructed, superposing these structures on the AR-bonded dihydrotestosterone (DHT) skeleton obtained from PDB (AR complex, ID 1I37). The parameters characterizing the HM vertices were collected using: AM1 charges, XlogP fragmental values, calculated fragmental polarizabilities (from refractivities), volumes, and H-bond parameters (Raevsky's thermodynamic originated scale). The resulted QSAR data matrix was submitted to PCA (Principal Component Analysis) and PLS (Projections in Latent Structures) procedure (SIMCA P 9.0); five compounds were selected as test set, and the remaining 25 molecules were used as training set. In the PLS procedure supplementary chemical information was introduced, i.e. the steric effect was always considered detrimental, and the hydrophobic and van der Waals interactions were imposed to be beneficial. The initial PLS model using the entire training set has the following characteristics: R2Y = 0.584, Q2 = 0.344. Based on distances to the model criterions (DMODX and DMODY), five compounds were eliminated and the obtained final model had the following characteristics: R2Y D 0.891, Q2 D 0.591. For this the external predictivity on the test set was unsatisfactory. A tentative explanation for these behaviors is the weak information content of the input QSAR matrix for the present series comparatively with other successful MTD-PLS modeling published elsewhere.
MECHANISMS IN ENDOCRINOLOGY: The sexually dimorphic role of androgens in human metabolic disease
Schiffer, Lina; Kempegowda, Punith; Arlt, Wiebke
2017-01-01
Female androgen excess and male androgen deficiency manifest with an overlapping adverse metabolic phenotype, including abdominal obesity, insulin resistance, type 2 diabetes mellitus, non-alcoholic fatty liver disease and an increased risk of cardiovascular disease. Here, we review the impact of androgens on metabolic target tissues in an attempt to unravel the complex mechanistic links with metabolic dysfunction; we also evaluate clinical studies examining the associations between metabolic disease and disorders of androgen metabolism in men and women. We conceptualise that an equilibrium between androgen effects on adipose tissue and skeletal muscle underpins the metabolic phenotype observed in female androgen excess and male androgen deficiency. Androgens induce adipose tissue dysfunction, with effects on lipid metabolism, insulin resistance and fat mass expansion, while anabolic effects on skeletal muscle may confer metabolic benefits. We hypothesise that serum androgen concentrations observed in female androgen excess and male hypogonadism are metabolically disadvantageous, promoting adipose and liver lipid accumulation, central fat mass expansion and insulin resistance. PMID:28566439
MECHANISMS IN ENDOCRINOLOGY: The sexually dimorphic role of androgens in human metabolic disease.
Schiffer, Lina; Kempegowda, Punith; Arlt, Wiebke; O'Reilly, Michael W
2017-09-01
Female androgen excess and male androgen deficiency manifest with an overlapping adverse metabolic phenotype, including abdominal obesity, insulin resistance, type 2 diabetes mellitus, non-alcoholic fatty liver disease and an increased risk of cardiovascular disease. Here, we review the impact of androgens on metabolic target tissues in an attempt to unravel the complex mechanistic links with metabolic dysfunction; we also evaluate clinical studies examining the associations between metabolic disease and disorders of androgen metabolism in men and women. We conceptualise that an equilibrium between androgen effects on adipose tissue and skeletal muscle underpins the metabolic phenotype observed in female androgen excess and male androgen deficiency. Androgens induce adipose tissue dysfunction, with effects on lipid metabolism, insulin resistance and fat mass expansion, while anabolic effects on skeletal muscle may confer metabolic benefits. We hypothesise that serum androgen concentrations observed in female androgen excess and male hypogonadism are metabolically disadvantageous, promoting adipose and liver lipid accumulation, central fat mass expansion and insulin resistance. © 2017 The authors.
Cytosolic androgen receptor in regenerating rat levator ani muscle.
Max, S R; Mufti, S; Carlson, B M
1981-01-01
The development of the cytosolic androgen receptor was studied after degeneration and regeneration of the rat levator ani muscle after a crush lesion. Muscle regeneration appears to recapitulate myogenesis in many respects. It therefore provides a model tissue in sufficiently in large quantity for investigating the ontogenesis of the androgen receptor. The receptor in the cytosol of the normal levator ani muscle has binding characteristics similar to those of the cytosolic receptor in other androgen-sensitive tissues. By day 3 after a crush lesion of the levator ani muscle, androgen binding decreased to 25% of control values. This decrease was followed by a 4-5 fold increase in hormone binding, which attained control values by day 7 after crush. Androgen binding remained stable at the control value up to day 60 after crushing. These results were correlated with the morphological development of the regenerating muscle after crushing. It is concluded that there is little, if any, androgen receptor present in the early myoblastic stages of regeneration; rather, synthesis of the receptor may occur after the fusion of myoblasts and during the differentiation of myotubes into cross-striated muscle fibres. Images PLATE 1 PLATE 2 PMID:6977357
Targets to treat androgen excess in polycystic ovary syndrome.
Luque-Ramírez, Manuel; Escobar-Morreale, Héctor Francisco
2015-01-01
The polycystic ovary syndrome (PCOS) is a common androgen disorder in reproductive-aged women. Excessive biosynthesis and secretion of androgens by steroidogenic tissues is its central pathogenetic mechanism. The authors review the potential targets and new drugs to treat androgen excess in PCOS. Besides our lab's experience, a systematic search (MEDLINE, Cochrane library, ClinicalTriasl.gov, EU Clinical Trials Register and hand-searching) regarding observational studies, randomized clinical trials, systematic reviews, meta-analyses and patents about this topic was performed. PCOS has a heterogeneous clinical presentation. It is unlikely that a single drug would cover all its possible manifestations. Available treatments for androgen excess are not free of side effects that are of particular concern in these women who suffer from cardiometabolic risk even without treatment. A precise characterization of the source of androgen excess must tailor antiandrogenic management in each woman, avoiding undesirable side effects.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vasiliou, M.; Lumbroso, R.; Alvarado, C.
1994-09-01
The stereochemistry of the androgen receptor (AR) that is responsible for androgen-specific binding and for its contribution to the transregulatory attributes of an androgen-receptor complex are unknown. Our objective is to define structure-function relations of the human AR by correlating germline missense mutations at its X-linked locus with its resultant misbehavior. Subjects with Arg773Cys have complete androgen insensitivity. We and several other laboratories have reported that their genital skin fibroblasts (GSF) have negligible androgen-binding activity at 37{degrees}. We have found that Phe763Leu also causes CAI, but with approximately 10 fmol/mg protein androgen-binding activity at 37{degrees} (R-deficient). Within COS-1 cells transfectedmore » with each mutant AR cDNA, Phe763Leu and Arg773Cys androgen-binding activities are reversibly thermolabile, by a factor of 2, at 37{degrees} versus 22{degrees}, only in the presence of androgen; in the absence of androgen they are thermostable at 37{degrees}. We have discovered that (for a reason yet unknown) the GSF from a third family with Arg773Cys (and no other coding sequence mutation) have 20-40 mol/mg protein of androgen-binding activity at 37{degrees} when measured with 3-6 nFM androgen. This activity reversibly doubles at 22{degrees}. The reversible thermolability of an AR with Arg773Cys (and probably with Phe763Leu) is demonstrable within GSF. Ligand-dependence of this thermolability implies that ligand induces these mutant AR to undergo a deviant conformational change in, or near, a 14-aa region that shares 90% identity/similarity with its closest receptor relatives.« less
Structure-based Virtual Screening and Identification of a Novel Androgen Receptor Antagonist*
Song, Chin-Hee; Yang, Su Hui; Park, Eunsook; Cho, Suk Hee; Gong, Eun-Yeung; Khadka, Daulat Bikram; Cho, Won-Jea; Lee, Keesook
2012-01-01
Hormonal therapies, mainly combinations of anti-androgens and androgen deprivation, have been the mainstay treatment for advanced prostate cancer because the androgen-androgen receptor (AR) system plays a pivotal role in the development and progression of prostate cancers. However, the emergence of androgen resistance, largely due to inefficient anti-hormone action, limits the therapeutic usefulness of these therapies. Here, we report that 6-(3,4-dihydro-1H-isoquinolin-2-yl)-N-(6-methylpyridin-2-yl)nicotinamide (DIMN) acts as a novel anti-androgenic compound that may be effective in the treatment of both androgen-dependent and androgen-independent prostate cancers. Through AR structure-based virtual screening using the FlexX docking model, fifty-four compounds were selected and further screened for AR antagonism via cell-based tests. One compound, DIMN, showed an antagonistic effect specific to AR with comparable potency to that of the classical AR antagonists, hydroxyflutamide and bicalutamide. Consistent with their anti-androgenic activity, DIMN inhibited the growth of androgen-dependent LNCaP prostate cancer cells. Interestingly, the compound also suppressed the growth of androgen-independent C4–2 and CWR22rv prostate cancer cells, which express a functional AR, but did not suppress the growth of the AR-negative prostate cancer cells PPC-1, DU145, and R3327-AT3.1. Taken together, the results suggest that the synthetic compound DIMN is a novel anti-androgen and strong candidate for useful therapeutic agent against early stage to advanced prostate cancer. PMID:22798067
Effects of androgenic-anabolic steroids in athletes.
Hartgens, Fred; Kuipers, Harm
2004-01-01
. Generally, AAS seem to induce increments of aggression and hostility. Mood disturbances (e.g. depression, [hypo-]mania, psychotic features) are likely to be dose and drug dependent. AAS dependence or withdrawal effects (such as depression) seem to occur only in a small number of AAS users. Dissatisfaction with the body and low self-esteem may lead to the so-called 'reverse anorexia syndrome' that predisposes to the start of AAS use. Many other adverse effects have been associated with AAS misuse, including disturbance of endocrine and immune function, alterations of sebaceous system and skin, changes of haemostatic system and urogenital tract. One has to keep in mind that the scientific data may underestimate the actual untoward effects because of the relatively low doses administered in those studies, since they do not approximate doses used by illicit steroid users. The mechanism of action of AAS may differ between compounds because of variations in the steroid molecule and affinity to androgen receptors. Several pathways of action have been recognised. The enzyme 5-alpha-reductase seems to play an important role by converting AAS into dihydrotestosterone (androstanolone) that acts in the cell nucleus of target organs, such as male accessory glands, skin and prostate. Other mechanisms comprises mediation by the enzyme aromatase that converts AAS in female sex hormones (estradiol and estrone), antagonistic action to estrogens and a competitive antagonism to the glucocorticoid receptors. Furthermore, AAS stimulate erythropoietin synthesis and red cell production as well as bone formation but counteract bone breakdown. The effects on the cardiovascular system are proposed to be mediated by the occurrence of AAS-induced atherosclerosis (due to unfavourable influence on serum lipids and lipoproteins), thrombosis, vasospasm or direct injury to vessel walls, or may be ascribed to a combination of the different mechanisms. AAS-induced increment of muscle tissue can be attributed
Price, Douglas K; Chau, Cindy H; Till, Cathee; Goodman, Phyllis J; Leach, Robin J; Johnson-Pais, Teresa L; Hsing, Ann W; Hoque, Ashraful; Parnes, Howard L; Schenk, Jeannette M; Tangen, Catherine M; Thompson, Ian M; Reichardt, Juergen K V; Figg, William D
2016-08-01
Prostate cancer is highly influenced by androgens and genes. The authors investigated whether genetic polymorphisms along the androgen biosynthesis and metabolism pathways are associated with androgen concentrations or with the risk of prostate cancer or high-grade disease from finasteride treatment. A nested case-control study from the Prostate Cancer Prevention Trial using data from men who had biopsy-proven prostate cancer (cases) and a group of biopsy-negative, frequency-matched controls was conducted to investigate the association of 51 single nucleotide polymorphisms (SNPs) in 12 genes of the androgen pathway with overall (total), low-grade, and high-grade prostate cancer incidence and serum hormone concentrations. There were significant associations of genetic polymorphisms in steroid 5α-reductase 1 (SRD5A1) (reference SNPs: rs3736316, rs3822430, rs1560149, rs248797, and rs472402) and SRD5A2 (rs2300700) with the risk of high-grade prostate cancer in the placebo arm of the Prostate Cancer Prevention Trial; 2 SNPs were significantly associated with an increased risk (SRD5A1 rs472402 [odds ratio, 1.70; 95% confidence interval, 1.05-2.75; Ptrend = .03] and SRD5A2 rs2300700 [odds ratio, 1.94; 95% confidence interval, 1.19-3.18; Ptrend = .01]). Eleven SNPs in SRD5A1, SRD5A2, cytochrome P450 family 1, subfamily B, polypeptide 1 (CYP1B1), and CYP3A4 were associated with modifying the mean concentrations of serum androgen and sex hormone-binding globulin; and 2 SNPs (SRD5A1 rs824811 and CYP1B1 rs10012; Ptrend < .05) consistently and significantly altered all androgen concentrations. Several SNPs (SRD5A1 rs3822430, SRD5A2 rs2300700, CYP3A43 rs800672, and CYP19 rs700519; Ptrend < .05) were significantly associated with both circulating hormone levels and prostate cancer risk. Germline genetic variations of androgen-related pathway genes are associated with serum androgen concentrations and the risk of prostate cancer. Further studies to examine the functional
Urinary androgens and cortisol metabolites in field-sampled bonobos (Pan paniscus).
Dittami, John; Katina, Stanislav; Möstl, Erich; Eriksson, Jonas; Machatschke, Ivo H; Hohmann, Gottfried
2008-02-01
Urinary metabolites of androgens and cortisol were measured in free-living male and female bonobos. Sex differences and correlations between adrenal and gonadal steroid excretion were investigated. The immunoreactive concentrations of androgens were measured with two different androgen assays. One assay used a testosterone (T) antibody raised with a 17beta-hydroxy group, and the other employed an antibody raised against a reduced form, 5alpha-androstane-17alpha-ol-3-one-CM (17alpha) with cross reactivity for epitestosterone and 5alpha-androstanedione. Both assays have been used in bonobo and chimpanzee studies where non-invasive techniques were employed. The levels of 17alpha-androgen metabolites were 1.7- and 3-fold higher than those of T-metabolites in males and females. The two androgen assay results correlated in males but not females. There was a sex difference in the T-metabolites measured. Male levels were significantly higher. Levels of 17alpha in the two sexes were similar. Cortisol metabolite levels (CORT) were similar between the sexes. The T-metabolites were significantly correlated with CORT in males but not in females. In females, the 17alpha-androgen metabolites correlated with CORT. This suggests that either androgen secretion or metabolism differs between the sexes. A parsimonious interpretation of the androgen assay cortisol/androgen correlation differences would be that larger components of dehydroepiandrosterone (DHEA), androstenedione or epitestosterone from the adrenal androgens were being excreted and measured in the females. The CORT/T metabolite interactions in males may reflect male-specific social or metabolic endocrine conditions.
Peng, Ruixian; Li, Zhenyu; Lin, Zhiyuan; Wang, Yang; Wang, Wei; Hu, Bo; Wang, Xilong; Zhang, Jun; Wang, Yangyun; Zhou, Renyuan; Lu, Chunhua; Shen, Yuemao; Wang, Jifeng; Shi, Guowei
2015-01-01
Castration-resistant prostate cancer (CRPC) ultimately occurs after a period of treatment with androgen deprivation therapy. Furthermore, CRPC patients can only derive limited survival benefits from traditional cytotoxic drugs. HSP90, which is a molecular chaperone, plays a vital role in client protein processing and maintaining the function of cells. HSP90 is usually overexpressed in prostate cancer tissues, which makes it a potential target for managing prostate cancer. Geldanamycin (GA), which was recognized as the first natural HSP90 inhibitor, has demonstrated potent anti-tumor efficacy in large-scale pre-clinical studies, but its application in the clinic is not permitted due to its liver toxicity and unstable physical properties. In this study, we report a new GA derivative, 17-PAG (17-(propynylamino)-17-demethoxygeldanamycin), which demonstrates highly effective anti-tumor activity against androgen-independent prostate cancer cells. Treating cells with 17-PAG dose-dependently suppressed proliferation, reduced colony formation and induced apoptosis of DU-145/C4-2B cells. Moreover, 17-PAG suppressed the migration and invasion of DU-145/C4-2B cells by regulating epithelial mesenchymal transition (EMT). 17-PAG also downregulated the HSP90 client proteins, including Her2, EGFR, C-Raf, AKT, p-AKT, and CDK4. Animal assays confirmed that 17-PAG shows strong anti-tumor effects with no obvious organ toxicity in DU-145 cell xenografted nude mice. These results provide us with a potential target for treating androgen-independent prostate cancer in a safe and effective manner. PMID:26693070
Patki, Mugdha; Huang, Yanfang; Ratnam, Manohar
2016-07-22
It is believed that growth of castration resistant prostate cancer (CRPC) cells is enabled by sensitization to minimal residual post-castrate androgen due to overexpression of the androgen receptor (AR). Evidence is derived from androgen-induced colony formation in the absence of cell-secreted factors or from studies involving forced AR overexpression in hormone-dependent cells. On the other hand, standard cell line models established from CRPC patient tumors (e.g., LNCaP and VCaP) are hormone-dependent and require selection pressure in castrated mice to re-emerge as CRPC cells and the resulting tumors then tend to be insensitive to the androgen antagonist enzalutamide. Therefore, we examined established CRPC model cells produced by castration of mice bearing hormone-dependent cell line xenografts including CRPC cells overexpressing full-length AR (C4-2) or co-expressing wtAR and splice-variant AR-V7 that is incapable of ligand binding (22Rv1). In standard colony formation assays, C4-2 cells were shown to be androgen-dependent and sensitive to enzalutamide whereas 22Rv1 cells were incapable of colony formation under identical conditions. However, both C4-2 and 22Rv1 cells formed colonies in conditioned media derived from the same cells or from HEK293 fibroblasts that were proven to lack androgenic activity. This effect was (i) not enhanced by androgen, (ii) insensitive to enzalutamide, (iii) dependent on AR (in C4-2) and on AR-V7 and wtAR (in 22Rv1) and (iv) sensitive to inhibitors of several signaling pathways, similar to androgen-stimulation. Therefore, during progression to CRPC in vivo, coordinate cellular changes accompanying overexpression of AR may enable cooperation between hormone-independent activity of AR and actions of cellular secretory factors to completely override androgen-dependence and sensitivity to drugs targeting hormonal factors. Copyright © 2016 Elsevier Inc. All rights reserved.
Androgens and Hypertension in Men and Women: a Unifying View.
Moretti, Costanzo; Lanzolla, Giulia; Moretti, Marta; Gnessi, Lucio; Carmina, Enrico
2017-05-01
This review was designed to revaluate the androgen role on the mechanisms of hypertension and cardiovascular risks in both men and women. Sex steroids are involved in the regulation of blood pressure, but pathophysiological mechanism is not well understood. Androgens have an important effect on metabolism, adipose and endothelial cell function, and cardiovascular risk in both men and women. A focal point in this contest is represented by the possible gender-specific regulation of different tissues and in particular of the adipose cell. Available data confirm that androgen deficiency is linked to increased prevalence of hypertension and cardiovascular diseases. Adipocyte dysfunction seems to be the main involved mechanism. Androgen replacement reduces inflammation state in man, protecting by metabolic syndrome progression. In women, androgen excess has been considered as promoting factor of cardiovascular risk. However, recent data suggest that excessive androgen production has little effect per se in inducing hypertension in young women of reproductive age. Also in postmenopausal women, data on relative androgen excess and hypertension are missing, while adrenal androgen deficiency has been associated to increased mortality. Molecular mechanisms linking androgen dysregulation to hypertension are almost Unknown, but they seem to be related to increased visceral fat, promoting a chronic inflammatory state through different mechanisms. One of these may involve the recruitment and over-activation of NF-kB, a ubiquitous transcription factor also expressed in adipose cells, where it may cause the production of cytokines and other immune factors. The NF-kB signalling pathway may also influence brown adipogenesis leading to the preferential enlargement of visceral adipocytes. Chronic inflammation and adipocyte dysfunction may alter endothelial function leading to hypertension. Both in men and in women, particularly in the post-menopausal period, hypoandrogenism seems to be
Bertin, Jonathan; Dury, Alain Y; Ouellet, Johanne; Pelletier, Georges; Labrie, Fernand
2014-08-01
To better understand the mechanisms underlying the beneficial effects of the intravaginal administration of dehydroepiandrosterone (DHEA) observed in postmenopausal women on sexual dysfunction. To identify the distribution of the androgen-synthesizing enzymes as well as androgen receptor (AR) and measure steroid levels in the monkey vagina. The cynomolgus monkey (Macaca fascicularis), the closest model to the human, has been used to measure the expression levels of steroidogenic enzymes and androgen receptor by quantitative reverse transcription polymerase chain reaction (n=4), confirmed by immunohistochemistry, and immunofluorescence (n=3). DHEA and its androgenic metabolites were quantified by LC-MS/MS (n=4). The presence of SRD5A1, SRD5A2, HSD17B3, AR as well as nerve fibers (PGP 9.5) was investigated, and steroid levels were measured. AR is widely distributed within the vaginal epithelium and also in the lamina propria with a lower expression in the muscularis layer and blood vessel walls. Androgen-forming enzymes, on the other hand, are expressed in the vaginal stratified squamous epithelium at a relatively high level where they are uniformly distributed from the basal membrane up to the superficial keratinized cells. The enzymes are at a lower level in blood vessel walls and zona muscularis where nerve fibers are localized. DHEA and its androgen metabolites are present at biologically significant concentrations in the monkey vagina. The enzymes responsible for androgen formation as well as AR are at the highest level in the superficial layer of the stratified epithelium and muscularis layers of the vagina. These data provide a potential explanation for the described role of androgens in regulating vaginal lubrication, smooth muscle activity, blood flow, and the neuronal activity potentially involved in the correction of sexual dysfunction. © 2014 International Society for Sexual Medicine.
Androgen antagonists in androgen target tissues.
Tindall, D J; Chang, C H; Lobl, T J; Cunningham, G R
1984-01-01
Most antiandrogens appear to act by binding to the androgen receptor and competitively inhibiting the binding of testosterone and cihydrotestosterone to the receptor. Focusing on those compounds which appear to inhibit androgen receptor mediated responses, this review discusses the chemistry of those antiandrogens which have been studied to the extent that their mechanism of action is at least partially understood, outlines the mechanism of androgen action as it is currently understood and suggests how antiandrogens might fit in with this mechanism, indicates the major metabolites of several important antiandrogens, and discusses the clinical applications of several antiandrogens. Cyproterone acetate has been studied extensively as a potential male contraceptive. Although it was recognized that 100 mg of cyproterone acetate per day inhibited spermatogenesis, that dose also reduced libido and potency. Following the administration of 10 or 20 mg of cyproterone acetate per day to 15 males for 26 weeks, the following observations were made: the number of motile sperm was reduced; the quality of their motion was impaired; and the ability of the sperm to penetrate cervical mucus was decreased. Sperm density was also suppressed, but neither it nor sperm motility were inhibited to the extent necessary for contraception. Antiandrogens have been demonstrated to be beneficial in treating 5 clinical syndromes or diseases: acne, seborrhea, hirsutism with or without menstrual abnormalities; precocious puberty; benign prostatic hypertrophy; cancer of the prostate; and sexual deviates. Since 3 of these conditions are very common, effective and safe treatment would have a large market. At this time, antiandrogens are widely used in Europe for treatment of seborrhea, acne, and hirsutism and a large Veterans Administration Cooperative Study in the US was approved but has not yet been funded to compare antiandrogens with other treatments for cancer of the prostate. Studies to assess
Androgen deprivation treatment of sexual behavior.
Houts, Frederick W; Taller, Inna; Tucker, Douglas E; Berlin, Fred S
2011-01-01
Gonadotropin-releasing hormone agonists are underutilized in patients seeking diminution of problematic sexual drives. This chapter reviews the literature on surgical castration of sex offenders, anti-androgen use and the rationale for providing androgen deprivation therapy, rather than selective serotonin reuptake inhibitors or more conservative interventions, for patients with paraphilias and excessive sexual drive. Discussions of informed consent, side effects, contraindications and case examples are provided. Copyright © 2011 S. Karger AG, Basel.
Androgen receptor: structure, role in prostate cancer and drug discovery
Tan, MH Eileen; Li, Jun; Xu, H Eric; Melcher, Karsten; Yong, Eu-leong
2015-01-01
Androgens and androgen receptors (AR) play a pivotal role in expression of the male phenotype. Several diseases, such as androgen insensitivity syndrome (AIS) and prostate cancer, are associated with alterations in AR functions. Indeed, androgen blockade by drugs that prevent the production of androgens and/or block the action of the AR inhibits prostate cancer growth. However, resistance to these drugs often occurs after 2–3 years as the patients develop castration-resistant prostate cancer (CRPC). In CRPC, a functional AR remains a key regulator. Early studies focused on the functional domains of the AR and its crucial role in the pathology. The elucidation of the structures of the AR DNA binding domain (DBD) and ligand binding domain (LBD) provides a new framework for understanding the functions of this receptor and leads to the development of rational drug design for the treatment of prostate cancer. An overview of androgen receptor structure and activity, its actions in prostate cancer, and how structural information and high-throughput screening have been or can be used for drug discovery are provided herein. PMID:24909511
ENVIRONMENTAL ANDROGENS AND ANTIANDROGENS: AN EXPANDING CHEMICAL UNIVERSE
Within the last ten years, awareness has grown about environmental chemicals that display antiandrogenic or androgenic activity. While studies in the early 1990s focused on pesticides that acted as androgen receptor (AR) antagonists, it soon became evident that this was not the ...
Androgens and endometrium: New insights and new targets.
Simitsidellis, Ioannis; Saunders, Philippa T K; Gibson, Douglas A
2018-04-15
Androgens are synthesised in both the ovary and adrenals in women and play an important role in the regulation of female fertility, as well as in the aetiology of disorders such as polycystic ovarian syndrome, endometriosis and endometrial cancer. The endometrium is an androgen target tissue and the impact of AR-mediated effects has been studied using human endometrial tissue samples and rodent models. In this review we highlight recent evidence that endometrial androgen biosynthesis and intracrine action is important in preparation of a tissue microenvironment that can support implantation and establishment of pregnancy. The impact of androgens on endometrial cell proliferation, in repair of the endometrial wound at the time of menstruation and in endometrial disorders is discussed. Future directions for research focused on AR function as a therapeutic target are considered. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.
Estrogens and Androgens in Skeletal Physiology and Pathophysiology
Almeida, Maria; Laurent, Michaël R.; Dubois, Vanessa; Claessens, Frank; O'Brien, Charles A.; Bouillon, Roger; Vanderschueren, Dirk
2016-01-01
Estrogens and androgens influence the growth and maintenance of the mammalian skeleton and are responsible for its sexual dimorphism. Estrogen deficiency at menopause or loss of both estrogens and androgens in elderly men contribute to the development of osteoporosis, one of the most common and impactful metabolic diseases of old age. In the last 20 years, basic and clinical research advances, genetic insights from humans and rodents, and newer imaging technologies have changed considerably the landscape of our understanding of bone biology as well as the relationship between sex steroids and the physiology and pathophysiology of bone metabolism. Together with the appreciation of the side effects of estrogen-related therapies on breast cancer and cardiovascular diseases, these advances have also drastically altered the treatment of osteoporosis. In this article, we provide a comprehensive review of the molecular and cellular mechanisms of action of estrogens and androgens on bone, their influences on skeletal homeostasis during growth and adulthood, the pathogenetic mechanisms of the adverse effects of their deficiency on the female and male skeleton, as well as the role of natural and synthetic estrogenic or androgenic compounds in the pharmacotherapy of osteoporosis. We highlight latest advances on the crosstalk between hormonal and mechanical signals, the relevance of the antioxidant properties of estrogens and androgens, the difference of their cellular targets in different bone envelopes, the role of estrogen deficiency in male osteoporosis, and the contribution of estrogen or androgen deficiency to the monomorphic effects of aging on skeletal involution. PMID:27807202
Androgen receptor signaling and mutations in prostate cancer
Koochekpour, Shahriar
2010-01-01
Normal and neoplastic growth of the prostate gland are dependent on androgen receptor (AR) expression and function. Androgenic activation of the AR, in association with its coregulatory factors, is the classical pathway that leads to transcriptional activity of AR target genes. Alternatively, cytoplasmic signaling crosstalk of AR by growth factors, neurotrophic peptides, cytokines or nonandrogenic hormones may have important roles in prostate carcinogenesis and in metastatic or androgen-independent (AI) progression of the disease. In addition, cross-modulation by various nuclear transcription factors acting through basal transcriptional machinery could positively or negatively affect the AR or AR target genes expression and activity. Androgen ablation leads to an initial favorable response in a significant number of patients; however, almost invariably patients relapse with an aggressive form of the disease known as castration-resistant or hormone-refractory prostate cancer (PCa). Understanding critical molecular events that lead PCa cells to resist androgen-deprivation therapy is essential in developing successful treatments for hormone-refractory disease. In a significant number of hormone-refractory patients, the AR is overexpressed, mutated or genomically amplified. These genetic alterations maintain an active presence for a highly sensitive AR, which is responsive to androgens, antiandrogens or nonandrogenic hormones and collectively confer a selective growth advantage to PCa cells. This review provides a brief synopsis of the AR structure, AR coregulators, posttranslational modifications of AR, duality of AR function in prostate epithelial and stromal cells, AR-dependent signaling, genetic changes in the form of somatic and germline mutations and their known functional significance in PCa cells and tissues. PMID:20711217
Estrogens and Androgens in Skeletal Physiology and Pathophysiology.
Almeida, Maria; Laurent, Michaël R; Dubois, Vanessa; Claessens, Frank; O'Brien, Charles A; Bouillon, Roger; Vanderschueren, Dirk; Manolagas, Stavros C
2017-01-01
Estrogens and androgens influence the growth and maintenance of the mammalian skeleton and are responsible for its sexual dimorphism. Estrogen deficiency at menopause or loss of both estrogens and androgens in elderly men contribute to the development of osteoporosis, one of the most common and impactful metabolic diseases of old age. In the last 20 years, basic and clinical research advances, genetic insights from humans and rodents, and newer imaging technologies have changed considerably the landscape of our understanding of bone biology as well as the relationship between sex steroids and the physiology and pathophysiology of bone metabolism. Together with the appreciation of the side effects of estrogen-related therapies on breast cancer and cardiovascular diseases, these advances have also drastically altered the treatment of osteoporosis. In this article, we provide a comprehensive review of the molecular and cellular mechanisms of action of estrogens and androgens on bone, their influences on skeletal homeostasis during growth and adulthood, the pathogenetic mechanisms of the adverse effects of their deficiency on the female and male skeleton, as well as the role of natural and synthetic estrogenic or androgenic compounds in the pharmacotherapy of osteoporosis. We highlight latest advances on the crosstalk between hormonal and mechanical signals, the relevance of the antioxidant properties of estrogens and androgens, the difference of their cellular targets in different bone envelopes, the role of estrogen deficiency in male osteoporosis, and the contribution of estrogen or androgen deficiency to the monomorphic effects of aging on skeletal involution. Copyright © 2017 the American Physiological Society.
Androgens and esophageal cancer: What do we know?
Sukocheva, Olga A; Li, Bin; Due, Steven L; Hussey, Damian J; Watson, David I
2015-05-28
Significant disparities exist between genders for the development and progression of several gastro-intestinal (GI) diseases including cancer. Differences in incidence between men vs women for colon, gastric and hepatocellular cancers suggest a role for steroid sex hormones in regulation of GI carcinogenesis. Involvement of intrinsic gender-linked mechanisms is also possible for esophageal adenocarcinoma as its incidence is disproportionally high among men. However, the cause of the observed gender differences and the potential role of androgens in esophageal carcinogenesis remains unclear, even though the cancer-promoting role of androgen receptors (AR) shown in other cancers such as prostate and bladder suggests this aspect warrants exploration. Several studies have demonstrated expression of ARs in esophageal cancer. However, only one study has suggested a potential link between AR signaling and outcome - poorer prognosis. Two groups have analyzed data from cohorts with prostate cancer and one of these found a decreased incidence of esophageal squamous and adenocarcinoma after androgen deprivation therapy. However, very limited information is available about the effects of androgen and AR-initiated signaling on esophageal cancer cell growth in vitro and in vivo. Possible mechanisms for androgens/AR involvement in the regulation of esophageal cancer growth are considered, and the potential use of AR as a prognostic factor and clinical target is highlighted, although insufficient evidence is available to support clinical trials of novel therapies. As esophageal adenocarcinoma is a gender linked cancer with a large male predominance further studies are warranted to clarify the role of androgens and ARs in shaping intracellular signaling and genomic responses in esophageal cancer.
Androgen receptor agonism promotes an osteogenic gene program in preadipocytes
Hartig, Sean M.; Feng, Qin; Ochsner, Scott A.; Xiao, Rui; McKenna, Neil J.; McGuire, Sean E.; He, Bin
2013-01-01
Androgens regulate body composition by interacting with the androgen receptor (AR) to control gene expression in a tissue-specific manner. To identify novel regulatory roles for AR in preadipocytes, we created a 3T3-L1 cell line stably expressing human AR. We found AR expression is required for androgen-mediated inhibition of 3T3-L1 adipogenesis. This inhibition is characterized by decreased lipid accumulation, reduced expression of adipogenic genes, and induction of genes associated with osteoblast differentiation. Collectively, our results suggest androgens promote an osteogenic gene program at the expense of adipocyte differentiation. PMID:23567971
11-Oxygenated C19 Steroids Are the Predominant Androgens in Polycystic Ovary Syndrome.
O'Reilly, Michael W; Kempegowda, Punith; Jenkinson, Carl; Taylor, Angela E; Quanson, Jonathan L; Storbeck, Karl-Heinz; Arlt, Wiebke
2017-03-01
Androgen excess is a defining feature of polycystic ovary syndrome (PCOS), but the exact origin of hyperandrogenemia remains a matter of debate. Recent studies have highlighted the importance of the 11-oxygenated C19 steroid pathway to androgen metabolism in humans. In this study, we analyzed the contribution of 11-oxygenated androgens to androgen excess in women with PCOS. One hundred fourteen women with PCOS and 49 healthy control subjects underwent measurement of serum androgens by liquid chromatography-tandem mass spectrometry. Twenty-four-hour urinary androgen excretion was analyzed by gas chromatography-mass spectrometry. Fasting plasma insulin and glucose were measured for homeostatic model assessment of insulin resistance. Baseline demographic data, including body mass index, were recorded. As expected, serum concentrations of the classic androgens testosterone (P < 0.001), androstenedione (P < 0.001), and dehydroepiandrosterone (P < 0.01) were significantly increased in PCOS. Mirroring this, serum 11-oxygenated androgens 11β-hydroxyandrostenedione, 11-ketoandrostenedione, 11β-hydroxytestosterone, and 11-ketotestosterone were significantly higher in PCOS than in control subjects, as was the urinary 11-oxygenated androgen metabolite 11β-hydroxyandrosterone. The proportionate contribution of 11-oxygenated to total serum androgens was significantly higher in patients with PCOS compared with control subjects [53.0% (interquartile range, 48.7 to 60.3) vs 44.0% (interquartile range, 32.9 to 54.9); P < 0.0001]. Obese (n = 51) and nonobese (n = 63) patients with PCOS had significantly increased 11-oxygenated androgens. Serum 11β-hydroxyandrostenedione and 11-ketoandrostenedione correlated significantly with markers of insulin resistance. We show that 11-oxygenated androgens represent the majority of circulating androgens in women with PCOS, with close correlation to markers of metabolic risk.
Androgen Effects on Adipose Tissue Architecture and Function in Nonhuman Primates
Varlamov, Oleg; White, Ashley E.; Carroll, Julie M.; Bethea, Cynthia L.; Reddy, Arubala; Slayden, Ov; O'Rourke, Robert W.
2012-01-01
The differential association of hypoandrogenism in men and hyperandrogenism in women with insulin resistance and obesity suggests that androgens may exert sex-specific effects on adipose and other tissues, although the underlying mechanisms remain poorly understood. Moreover, recent studies also suggest that rodents and humans may respond differently to androgen imbalance. To achieve better insight into clinically relevant sex-specific mechanisms of androgen action, we used nonhuman primates to investigate the direct effects of gonadectomy and hormone replacement on white adipose tissue. We also employed a novel ex vivo approach that provides a convenient framework for understanding of adipose tissue physiology under a controlled tissue culture environment. In vivo androgen deprivation of males did not result in overt obesity or insulin resistance but did induce the appearance of very small, multilocular white adipocytes. Testosterone replacement restored normal cell size and a unilocular phenotype and stimulated adipogenic gene transcription and improved insulin sensitivity of male adipose tissue. Ex vivo studies demonstrated sex-specific effects of androgens on adipocyte function. Female adipose tissue treated with androgens displayed elevated basal but reduced insulin-dependent fatty acid uptake. Androgen-stimulated basal uptake was greater in adipose tissue of ovariectomized females than in adipose tissue of intact females and ovariectomized females replaced with estrogen and progesterone in vivo. Collectively, these data demonstrate that androgens are essential for normal adipogenesis in males and can impair essential adipocyte functions in females, thus strengthening the experimental basis for sex-specific effects of androgens in adipose tissue. PMID:22547568
Prior, Lynn; Bordet, Sylvie; Trifiro, Mark A.; Mhatre, Anand; Kaufman, Morris; Pinsky, Leonard; Wrogeman, Klaus; Belsham, Denise D.; Pereira, Fred; Greenberg, Cheryl; Trapman, Jan; Brinkman, Albert O.; Chang, Chawnshang; Liao, Shutsung
1992-01-01
We have discovered two different point mutations in a single codon of the X-linked androgen-receptor (AR) gene in two pairs of unrelated families who have complete androgen insensitivity (resistance) associated with different AR phenotypes in their genital skin fibroblasts. One mutation is a C-to-T transition at a CpG sequence near the 5' terminus of exon 6; it changes the sense of codon 773 from arginine to cysteine, ablates specific androgen-binding activity at 37°C, and eliminates a unique KpnI site at the intron-exon boundary. The other mutation is a G-to-A transition that changes amino acid 773 to histidine and eliminates an SphI site. This mutant AR has a normal androgen-binding capacity at 37°C but has a reduced affinity for androgens and is thermolabile in their presence. Transient transfection of COS cells with cDNA expression vectors yielded little androgen-binding activity at 37°C from Arg773Cys and abundant activity with abnormal properties from Arg773His, thereby proving the pathogenicity of both sequence alterations. This conclusion coincides with the following facts about evolutionary preservation of the position homologous to Arg773 in the AR: it is occupied by Arg or lysine in the progesterone, glucocorticoid, and mineralocorticoid receptors, and it is within a 14-amino-acid region of their steroid-binding domains that share ∼85% amino acid identity. ImagesFigure 7Figure 2Figure 3Figure 5Figure 6Figure 8 PMID:1609793
Penguin chicks benefit from elevated yolk androgen levels under sibling competition.
Poisbleau, Maud; Müller, Wendt; Carslake, David; Demongin, Laurent; Groothuis, Ton G G; Van Camp, Jeff; Eens, Marcel
2012-01-01
Crested penguins (genus Eudyptes) have a peculiar hatching pattern, with the first-laid egg (A-egg) hatching after the second-laid egg (B-egg) and chicks from A-eggs typically having a much lower survival probability. Maternal yolk androgens have been suggested to contribute to the competitive superiority of the B-chick in southern rockhopper penguins Eudyptes chrysocome, given their important role in mediating sibling competition in other species. We therefore increased the yolk androgen levels in freshly-laid eggs and examined the consequences for sibling competition--via effects on embryonic developmental times, chick growth and early survival. We placed one androgen-treated egg and one control egg into each foster nest, matching them for mass, laying date and laying order. The androgen treatment did not significantly affect embryonic developmental times or chick measurements at hatching. However, elevated yolk androgen levels benefitted chick growth in interaction with the number of siblings in a brood. Chicks from androgen-treated eggs had faster growth in the presence of a sibling than chicks from control eggs. Under these circumstances they also had a higher survival probability. Thus maternal androgens appear to reinforce the observed hatching pattern, facilitating brood reduction. This contrasts to most previous studies in other species where yolk androgens have been shown to compensate for the negative consequences of delayed hatching within the brood hierarchy.
11-Oxygenated C19 Steroids Are the Predominant Androgens in Polycystic Ovary Syndrome
O’Reilly, Michael W.; Kempegowda, Punith; Jenkinson, Carl; Taylor, Angela E.; Quanson, Jonathan L.; Storbeck, Karl-Heinz
2017-01-01
Context: Androgen excess is a defining feature of polycystic ovary syndrome (PCOS), but the exact origin of hyperandrogenemia remains a matter of debate. Recent studies have highlighted the importance of the 11-oxygenated C19 steroid pathway to androgen metabolism in humans. In this study, we analyzed the contribution of 11-oxygenated androgens to androgen excess in women with PCOS. Methods: One hundred fourteen women with PCOS and 49 healthy control subjects underwent measurement of serum androgens by liquid chromatography-tandem mass spectrometry. Twenty-four–hour urinary androgen excretion was analyzed by gas chromatography-mass spectrometry. Fasting plasma insulin and glucose were measured for homeostatic model assessment of insulin resistance. Baseline demographic data, including body mass index, were recorded. Results: As expected, serum concentrations of the classic androgens testosterone (P < 0.001), androstenedione (P < 0.001), and dehydroepiandrosterone (P < 0.01) were significantly increased in PCOS. Mirroring this, serum 11-oxygenated androgens 11β-hydroxyandrostenedione, 11-ketoandrostenedione, 11β-hydroxytestosterone, and 11-ketotestosterone were significantly higher in PCOS than in control subjects, as was the urinary 11-oxygenated androgen metabolite 11β-hydroxyandrosterone. The proportionate contribution of 11-oxygenated to total serum androgens was significantly higher in patients with PCOS compared with control subjects [53.0% (interquartile range, 48.7 to 60.3) vs 44.0% (interquartile range, 32.9 to 54.9); P < 0.0001]. Obese (n = 51) and nonobese (n = 63) patients with PCOS had significantly increased 11-oxygenated androgens. Serum 11β-hydroxyandrostenedione and 11-ketoandrostenedione correlated significantly with markers of insulin resistance. Conclusions: We show that 11-oxygenated androgens represent the majority of circulating androgens in women with PCOS, with close correlation to markers of metabolic risk. PMID:27901631
Impact of Early Postnatal Androgen Exposure on Voice Development
Grisa, Leila; Leonel, Maria L.; Gonçalves, Maria I. R.; Pletsch, Francisco; Sade, Elis R.; Custódio, Gislaine; Zagonel, Ivete P. S.; Longui, Carlos A.; Figueiredo, Bonald C.
2012-01-01
Background The impact of early postnatal androgen exposure on female laryngeal tissue may depend on certain characteristics of this exposure. We assessed the impact of the dose, duration, and timing of early androgen exposure on the vocal development of female subjects who had been treated for adrenocortical tumor (ACT) in childhood. Methods The long-term effects of androgen exposure on the fundamental vocal frequency (F0), vocal pitch, and final height and the presence of virilizing signs were examined in 9 adult (age, 18.4 to 33.5 years) and 10 adolescent (13.6 to 17.8 years) female ACT patients. We also compared the current values with values obtained 0.9 years to 7.4 years after these subjects had undergone ACT surgery, a period during which they had shown normal androgen levels. Results Of the 19 subjects, 17 (89%) had been diagnosed with ACT before 4 years of age, 1 (5%) at 8.16 years, and 1 (5%) at 10.75 years. Androgen exposure (2 to 30 months) was sufficiently strong to cause pubic hair growth in all subjects and clitoromegaly in 74% (14/19) of the subjects, but did not reduce their height from the target value. Although androgen exposure induced a remarkable reduction in F0 (132 Hz) and moderate pitch virilization in 1 subject and partial F0 virilization, resulting in F0 of 165 and 169 Hz, in 2 subjects, the majority had normal F0 ranging from 189 to 245 Hz. Conclusions Female laryngeal tissue is less sensitive to androgen exposure between birth and adrenarche than during other periods. Differential larynx sensitivity to androgen exposure in childhood and F0 irreversibility in adulthood are age-, concentration-, duration-, and timing-dependent events that may also be affected by exposure to inhibitory or stimulatory hormones. Further studies are required to better characterize each of these factors. PMID:23284635
Glutathione S-transferase Pi mediates proliferation of androgen-independent prostate cancer cells
Hokaiwado, Naomi; Takeshita, Fumitaka; Naiki-Ito, Aya; Asamoto, Makoto; Ochiya, Takahiro; Shirai, Tomoyuki
2008-01-01
Prostate cancers generally acquire an androgen-independent growth capacity with progression, resulting in resistance to antiandrogen therapy. Therefore, identification of the genes regulated through this process may be important for understanding the mechanisms of prostate carcinogenesis. We here utilized androgen-dependent/independent transplantable tumors, newly established with the ‘transgenic rat adenocarcinoma in prostate’ (TRAP) model, to analyze their gene expression using microarrays. Among the overexpressed genes in androgen-independent prostate cancers compared with the androgen-dependent tumors, glutathione S-transferase pi (GST-pi) was included. In line with this, human prostate cancer cell lines PC3 and DU145 (androgen independent) had higher expression of GST-pi compared with LNCaP (androgen dependent) as determined by semiquantitative reverse transcription–polymerase chain reaction analysis. To investigate the roles of GST-pi expression in androgen-independent human prostate cancers, GST-pi was knocked down by a small interfering RNA (siRNA), resulting in significant decrease of the proliferation rate in the androgen-independent PC3 cell line. In vivo, administration of GST-pi siRNA–atelocollagen complex decreased GST-pi protein expression, resulting in enhanced numbers of TdT mediated dUTP-biotin nick-end labering (TUNEL)-positive apoptotic cells. These findings suggest that GST-pi might play important roles in proliferation of androgen-independent human prostate cancer cells. PMID:18413363
Hilborn, Erik; Stål, Olle; Jansson, Agneta
2017-01-01
Sex steroid hormones such as estrogens and androgens are involved in the development and differentiation of the breast tissue. The activity and concentration of sex steroids is determined by the availability from the circulation, and on local conversion. This conversion is primarily mediated by aromatase, steroid sulfatase, and 17β-hydroxysteroid dehydrogenases. In postmenopausal women, this is the primary source of estrogens in the breast. Up to 70-80% of all breast cancers express the estrogen receptor-α, responsible for promoting the growth of the tissue. Further, 60-80% express the androgen receptor, which has been shown to have tissue protective effects in estrogen receptor positive breast cancer, and a more ambiguous response in estrogen receptor negative breast cancers. In this review, we summarize the function and clinical relevance in cancer for 17β-hydroxysteroid dehydrogenases 1, which facilitates the reduction of estrone to estradiol, dehydroepiandrosterone to androstendiol and dihydrotestosterone to 3α- and 3β-diol as well as 17β-hydroxysteroid dehydrogenases 2 which mediates the oxidation of estradiol to estrone, testosterone to androstenedione and androstendiol to dehydroepiandrosterone. The expression of 17β-hydroxysteroid dehydrogenases 1 and 2 alone and in combination has been shown to predict patient outcome, and inhibition of 17β-hydroxysteroid dehydrogenases 1 has been proposed to be a prime candidate for inhibition in patients who develop aromatase inhibitor resistance or in combination with aromatase inhibitors as a first line treatment. Here we review the status of inhibitors against 17β-hydroxysteroid dehydrogenases 1. In addition, we review the involvement of 17β-hydroxysteroid dehydrogenases 4, 5, 7, and 14 in breast cancer. PMID:28430630
Hilborn, Erik; Stål, Olle; Jansson, Agneta
2017-05-02
Sex steroid hormones such as estrogens and androgens are involved in the development and differentiation of the breast tissue. The activity and concentration of sex steroids is determined by the availability from the circulation, and on local conversion. This conversion is primarily mediated by aromatase, steroid sulfatase, and 17β-hydroxysteroid dehydrogenases. In postmenopausal women, this is the primary source of estrogens in the breast. Up to 70-80% of all breast cancers express the estrogen receptor-α, responsible for promoting the growth of the tissue. Further, 60-80% express the androgen receptor, which has been shown to have tissue protective effects in estrogen receptor positive breast cancer, and a more ambiguous response in estrogen receptor negative breast cancers. In this review, we summarize the function and clinical relevance in cancer for 17β-hydroxysteroid dehydrogenases 1, which facilitates the reduction of estrone to estradiol, dehydroepiandrosterone to androstendiol and dihydrotestosterone to 3α- and 3β-diol as well as 17β-hydroxysteroid dehydrogenases 2 which mediates the oxidation of estradiol to estrone, testosterone to androstenedione and androstendiol to dehydroepiandrosterone. The expression of 17β-hydroxysteroid dehydrogenases 1 and 2 alone and in combination has been shown to predict patient outcome, and inhibition of 17β-hydroxysteroid dehydrogenases 1 has been proposed to be a prime candidate for inhibition in patients who develop aromatase inhibitor resistance or in combination with aromatase inhibitors as a first line treatment. Here we review the status of inhibitors against 17β-hydroxysteroid dehydrogenases 1. In addition, we review the involvement of 17β-hydroxysteroid dehydrogenases 4, 5, 7, and 14 in breast cancer.
Davey, Rachel A; Clarke, Michele V; Russell, Patricia K; Rana, Kesha; Seto, Jane; Roeszler, Kelly N; How, Jackie M Y; Chia, Ling Yeong; North, Kathryn; Zajac, Jeffrey D
2017-10-01
Although it is well established that exogenous androgens have anabolic effects on skeletal muscle mass in humans and mice, data from muscle-specific androgen receptor (AR) knockout (ARKO) mice indicate that myocytic expression of the AR is dispensable for hind-limb muscle mass accrual in males. To identify possible indirect actions of androgens via the AR in neurons to regulate muscle, we generated neuron-ARKO mice in which the dominant DNA binding-dependent actions of the AR are deleted in neurons of the cortex, forebrain, hypothalamus, and olfactory bulb. Serum testosterone and luteinizing hormone levels were elevated twofold in neuron-ARKO males compared with wild-type littermates due to disruption of negative feedback to the hypothalamic-pituitary-gonadal axis. Despite this increase in serum testosterone levels, which was expected to increase muscle mass, the mass of the mixed-fiber gastrocnemius (Gast) and the fast-twitch fiber extensor digitorum longus hind-limb muscles was decreased by 10% in neuron-ARKOs at 12 weeks of age, whereas muscle strength and fatigue of the Gast were unaffected. The mass of the soleus muscle, however, which consists of a high proportion of slow-twitch fibers, was unaffected in neuron-ARKOs, demonstrating a stimulatory action of androgens via the AR in neurons to increase the mass of fast-twitch hind-limb muscles. Furthermore, neuron-ARKOs displayed reductions in voluntary and involuntary physical activity by up to 60%. These data provide evidence for a role of androgens via the AR in neurons to positively regulate fast-twitch hind-limb muscle mass and physical activity in male mice. Copyright © 2017 Endocrine Society.
Exploring Androgen-Regulated Pathways in Teleost Fish Using Transcriptomics and Proteomics
Martyniuk, Christopher J.; Denslow, Nancy D.
2012-01-01
In the environment, there are aquatic pollutants that disrupt androgen signaling in fish. Laboratory and field-based experiments have utilized omics technologies to characterize the molecular mechanisms underlying androgen-receptor agonism/antagonism. Transcriptomics and proteomics studies with 17β-trenbolone, a growth-promoting pharmaceutical found in water systems surrounding cattle feed lots, and androgens such as 17α-methyltestosterone and 17α-methyldihydrotestosterone, have been conducted in ovary and liver of fish that include the fathead minnow (FHM) (Pimephales promelas), common carp (Cyprinus carpio), Qurt medaka (Oryzias latipes), and zebrafish (Danio rerio). In this mini-review, we survey recent omics studies in fish and reveal that, despite the diversity of species and tissues examined, there are common cellular responses that are observed with waterborne androgenic treatments. Recurring themes in gene ontology include apoptosis, transport and oxidation of lipids, synthesis and transport of hormones, immune response, protein metabolism, and cell proliferation. However, we also discuss other mechanisms other than androgen receptor (AR) activation, such as responses to toxicant stress, estrogen receptor agonism, aromatization of androgens into estrogens, and inhibitory feedback mechanisms by high levels of androgens that may also explain molecular responses in fish. To further explore androgen-responsive protein networks, a sub-network enrichment analysis was performed on protein data collected from the livers of female FHMs exposed to 17β-trenbolone. We construct a putative AR-regulated protein/cell process network in the liver that includes B-lymphocyte differentiation, xenobiotic clearance, low-density lipoprotein oxidation, proliferation of smooth muscle cells, and permeability of blood vessels. We demonstrate that construction of protein networks can offer insight into cell processes that are potentially regulated by androgens. PMID:22596056
Chen, Eddy J; Sowalsky, Adam G; Gao, Shuai; Cai, Changmeng; Voznesensky, Olga; Schaefer, Rachel; Loda, Massimo; True, Lawrence D; Ye, Huihui; Troncoso, Patricia; Lis, Rosina L; Kantoff, Philip W; Montgomery, Robert B; Nelson, Peter S; Bubley, Glenn J; Balk, Steven P; Taplin, Mary-Ellen
2015-03-15
The CYP17A1 inhibitor abiraterone markedly reduces androgen precursors and is thereby effective in castration-resistant prostate cancer (CRPC). However, abiraterone increases progesterone, which can activate certain mutant androgen receptors (AR) identified previously in flutamide-resistant tumors. Therefore, we sought to determine if CYP17A1 inhibitor treatment selects for progesterone-activated mutant ARs. AR was examined by targeted sequencing in metastatic tumor biopsies from 18 patients with CRPC who were progressing on a CYP17A1 inhibitor (17 on abiraterone, 1 on ketoconazole), alone or in combination with dutasteride, and by whole-exome sequencing in residual tumor in one patient treated with neoadjuvant leuprolide plus abiraterone. The progesterone-activated T878A-mutant AR was present at high allele frequency in 3 of the 18 CRPC cases. It was also present in one focus of resistant tumor in the neoadjuvant-treated patient, but not in a second clonally related resistant focus that instead had lost one copy of PTEN and both copies of CHD1. The T878A mutation appeared to be less common in the subset of patients with CRPC treated with abiraterone plus dutasteride, and transfection studies showed that dutasteride was a more potent direct antagonist of the T878A versus the wild-type AR. These findings indicate that selection for tumor cells expressing progesterone-activated mutant ARs is a mechanism of resistance to CYP17A1 inhibition. ©2014 American Association for Cancer Research.
Complex modulation of androgen responsive gene expression by methoxyacetic acid
2011-01-01
Background Optimal androgen signaling is critical for testicular development and spermatogenesis. Methoxyacetic acid (MAA), the primary active metabolite of the industrial chemical ethylene glycol monomethyl ether, disrupts spermatogenesis and causes testicular atrophy. Transcriptional trans-activation studies have indicated that MAA can enhance androgen receptor activity, however, whether MAA actually impacts the expression of androgen-responsive genes in vivo, and which genes might be affected is not known. Methods A mouse TM3 Leydig cell line that stably expresses androgen receptor (TM3-AR) was prepared and analyzed by transcriptional profiling to identify target gene interactions between MAA and testosterone on a global scale. Results MAA is shown to have widespread effects on androgen-responsive genes, affecting processes ranging from apoptosis to ion transport, cell adhesion, phosphorylation and transcription, with MAA able to enhance, as well as antagonize, androgenic responses. Moreover, testosterone is shown to exert both positive and negative effects on MAA gene responses. Motif analysis indicated that binding sites for FOX, HOX, LEF/TCF, STAT5 and MEF2 family transcription factors are among the most highly enriched in genes regulated by testosterone and MAA. Notably, 65 FOXO targets were repressed by testosterone or showed repression enhanced by MAA with testosterone; these include 16 genes associated with developmental processes, six of which are Hox genes. Conclusions These findings highlight the complex interactions between testosterone and MAA, and provide insight into the effects of MAA exposure on androgen-dependent processes in a Leydig cell model. PMID:21453523
[Effects of androgens and gestagens on uterine myoma].
Pashkova, V S; Erokhin, Iu A
1991-01-01
One hundred and sixty resected intramural myomas have been examined in 78 women with an intact menstrual cycle: 61 nodes from 31 patients of 37 to 57 years without a history of hormonal treatment, 52 nodes from 26 patients of 39 to 57 years with a history of androgen treatment and 47 nodes from 21 women of 30 to 50 years with a history of gestagen treatment. The histologic, histochemical, morphometric and biochemical studies showed that androgen and gestagen treatment stabilized and diminished the myomas, promoted secondary changes in the nodes and caused a statistically significant activation of sclerotic processes. Therapeutic effects of androgens were superior to those of gestagens.
Indirect androgen doping by oestrogen blockade in sports
Handelsman, D J
2008-01-01
Androgens can increase muscular mass and strength and remain the most frequently abused and widely available drugs used in sports doping. Banning the administration of natural or synthetic androgens has led to a variety of strategies to circumvent the ban of the most effective ergogenic agents for power sports. Among these, a variety of indirect androgen doping strategies aiming to produce a sustained rise in endogenous testosterone have been utilized. These include oestrogen blockade by drugs that act as oestrogen receptor antagonists (antioestrogen) or aromatase inhibitors. The physiological and pharmacological basis for the effects of oestrogen blockade in men, but not women, are reviewed. PMID:18500381
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kumar, Rajeev; Verma, Vikas; Sharma, Vikas
Dietary consumption of phytoestrogens like genistein has been linked with lower incidence of prostate cancer. The estradiol-like benzopyran core of genistein confers estrogen receptor-β (ER-β) selectivity that imparts weak anti-proliferative activity against prostate cancer cells. DL-2-[4-(2-piperidinoethoxy)phenyl]-3-phenyl-2H-1-benzopyran (BP), a SERM designed with benzopyran core, targeted androgen independent prostate cancer (PC-3) cells 14-times more potently than genistein, ~ 25% more efficiently than tamoxifen and 6.5-times more actively than ICI-182780, without forfeiting significant specificity in comparison to genistein. BP increased apoptosis (annexin-V and TUNEL labeling), arrested cell cycle, and significantly increased caspase-3 activity along with mRNA expressions of estrogen receptor (ER)-β and FasLmore » (qPCR) in PC-3 cells. In classical ERE-luc reporter assay BP behaved as a potent ER-α antagonist and ER-β agonist. Accordingly, it decreased expression of ER-α target PS2 (P < 0.01) and increased expression of ER-β target TNF-α (P < 0.05) genes in PC-3. ER-β deficient PC-3 (siRNA-transfected) was resistant to apoptotic and anti-proliferative actions of SERMs, including stimulation of FasL expression by BP. BP significantly inhibited phosphorylation of Akt and ERK-1/2, JNK and p38 in PC-3 (immunoblotting), and thus adopted a multi-pathway mechanism to exert a more potent anti-proliferative activity against prostate cancer cells than natural and synthetic SERMs. Its precise ER-subtype specific activity presents a unique lead structure for further optimization. - Highlights: • BP with benzopyran core of genistein was identified for ER-β selective action. • BP was 14-times more potent than genistien in targeting prostate cancer cells. • It behaved as a potent ER-β agonist and ER-α antagonist in gene reporter assays. • BP's anti-proliferative action was inhibited significantly in ER-β deficient cells. • BP — a unique lead
Sehgal, I; Powers, S; Huntley, B; Powis, G; Pittelkow, M; Maihle, N J
1994-01-01
After therapeutic hormone deprivation, prostate cancer cells often develop androgen-insensitive growth through mechanisms thus far undefined. Neuropeptides have been previously implicated as growth factors in some prostate cancers. Here, we demonstrate that androgen-sensitive LNCaP human prostate cancer cells produce and secrete neurotensin following androgen withdrawal. We show that while LNCaP cells express the neurotensin receptor, only androgen-deprived cells exhibit a growth response to exogenous neurotensin. We further demonstrate that androgen-stimulated cells may be refractory to exogenous neurotensin due to androgen induction of a metalloprotease active toward neurotensin. Thus, prostate cancer cells deprived of androgen develop an alternative autocrine growth mechanism involving neurotensin. Images PMID:8197117
Assessment of a recombinant androgen receptor binding assay: initial steps towards validation.
Freyberger, Alexius; Weimer, Marc; Tran, Hoai-Son; Ahr, Hans-Jürgen
2010-08-01
Despite more than a decade of research in the field of endocrine active compounds with affinity for the androgen receptor (AR), still no validated recombinant AR binding assay is available, although recombinant AR can be obtained from several sources. With funding from the European Union (EU)-sponsored 6th framework project, ReProTect, we developed a model protocol for such an assay based on a simple AR binding assay recently developed at our institution. Important features of the protocol were the use of a rat recombinant fusion protein to thioredoxin containing both the hinge region and ligand binding domain (LBD) of the rat AR (which is identical to the human AR-LBD) and performance in a 96-well plate format. Besides two reference compounds [dihydrotestosterone (DHT), androstenedione] ten test compounds with different affinities for the AR [levonorgestrel, progesterone, prochloraz, 17alpha-methyltestosterone, flutamide, norethynodrel, o,p'-DDT, dibutylphthalate, vinclozolin, linuron] were used to explore the performance of the assay. At least three independent experiments per compound were performed. The AR binding properties of reference and test compounds were well detected, in terms of the relative ranking of binding affinities, there was good agreement with published data obtained from experiments using recombinant AR preparations. Irrespective of the chemical nature of the compound, individual IC(50)-values for a given compound varied by not more than a factor of 2.6. Our data demonstrate that the assay reliably ranked compounds with strong, weak, and no/marginal affinity for the AR with high accuracy. It avoids the manipulation and use of animals, as a recombinant protein is used and thus contributes to the 3R concept. On the whole, this assay is a promising candidate for further validation. Copyright 2009 Elsevier Inc. All rights reserved.
Daan, N M P; Jaspers, L; Koster, M P H; Broekmans, F J M; de Rijke, Y B; Franco, O H; Laven, J S E; Kavousi, M; Fauser, B C J M
2015-10-01
pressure (β log FAI for PCOS: 0.05, P = 0.002, POI: 0.07, P < 0.001, NM: 0.04, P = 0.04) in all women; with increased glucose (β log FAI for PCOS: 0.05, P = 0.003, NM: 0.07, P < 0.001) and decreased high-density lipoprotein (β log FAI for PCOS: -0.23, P < 0.001, NM: -0.09, P = 0.03) in PCOS and NM women; and with increased low-density lipoprotein (β log FAI for POI: 0.083, P = 0.041) in POI women. Adjustment for BMI attenuated the observed associations. Associations between FAI and cardiometabolic features were the strongest in PCOS women, even after adjustment for BMI. Associations between androgen levels and cardiometabolic features were assessed in PCOS, POI and NM women only, due to a lack of available data in RC women. Due to the cross-sectional design of the current study, the potential associations between androgen levels and actual future cardiovascular events could not be assessed. This study affirms the potent effect of androgens on cardiometabolic features, indicating that