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1.
Endocr Relat Cancer ; 21(4): T119-29, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24872511

ABSTRACT

Androgen deprivation therapy (ADT) is increasingly used to treat advanced prostate cancer and is also utilised as adjuvant or neo-adjuvant treatment for high-risk disease. The resulting suppression of endogenous testosterone production has deleterious effects on quality of life, including hot flushes, reduced mood and cognition and diminished sexual function. Cross-sectional and longitudinal studies show that ADT has adverse bone and cardio-metabolic effects. The rate of bone loss is accelerated, increasing the risk of osteoporosis and subsequent fracture. Fat mass is increased and lean mass reduced, and adverse effects on lipid levels and insulin resistance are observed, the latter increasing the risk of developing type 2 diabetes. ADT also appears to increase the risk of incident cardiovascular events, although whether it increases cardiovascular mortality is not certain from the observational evidence published to date. Until high-quality evidence is available to guide management, it is reasonable to consider men undergoing ADT to be at a higher risk of psychosexual dysfunction, osteoporotic fracture, diabetes and cardiovascular disease, especially when treated for extended periods of time and therefore subjected to profound and prolonged hypoandrogenism. Health professionals caring for men undergoing treatment for prostate cancer should be aware of the potential risks of ADT and ensure appropriate monitoring and clinical management.


Subject(s)
Androgen Antagonists/adverse effects , Antineoplastic Agents/adverse effects , Prostatic Neoplasms/drug therapy , Affect/drug effects , Androgen Antagonists/therapeutic use , Antineoplastic Agents/therapeutic use , Bone Resorption/chemically induced , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/etiology , Cognition/drug effects , Hot Flashes/chemically induced , Humans , Male , Quality of Life , Sexual Dysfunction, Physiological/chemically induced
2.
Hum Reprod ; 23(2): 403-11, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18199736

ABSTRACT

BACKGROUND: Gonadotrophins support spermatogenesis via poorly understood mechanisms. We aimed to determine the effect of FSH/LH suppression in regulating germ cell apoptosis and proliferation in normal fertile men. METHODS: Testicular tissues were obtained after gonadotrophin suppression induced by testosterone alone or combined with depot medroxyprogesterone acetate for 2 or 6 weeks and an untreated group of men (referred to as 'normal men') served as controls (n = 5 or 10 men per group). Apoptosis and proliferation were identified by terminal deoxynucleotidyl transferase-mediated dUDP nick-end labelling (TUNEL) and proliferating cell nuclear antigen (PCNA) labelling methods, respectively. Intrinsic and extrinsic apoptotic pathways were identified by immunohistochemistry using the pathway-specific proteins: activated caspase (aCaspase) 9 and 8 and quantified using stereological techniques. RESULTS: By 2 and 6 weeks, the proportion of TUNEL-labelled spermatogonia increased to 354% and 268% respectively, compared with normal men (P < 0.001), with increased caspase 9 [223 and 166% compared with normal men (P < 0.001)], but no increase in caspase 8, immunoreactivity. At 6 weeks, the proportions of TUNEL-labelled spermatocytes and round spermatids tended to increase (303 and 180% compared with normal men, NS), as did caspase 9 (199 and 147% compared with normal men, NS) and caspase 8 immunoreactivities (286 and 243% compared with normal men, NS and P = 0.06), respectively. The proportion of TUNEL-labelled elongating/elongated spermatids tended to increase (144 and 138% compared with normal men, NS) at 2 and 6 weeks, respectively, with no change in either caspase immunoreactivities. Even though the number of PCNA-labelled cells did not change with gonadotrophin suppression, the balance between proliferation and apoptosis was lower in spermatogonia (P = 0.01) and spermatocytes (P = 0.3) between treated and untreated normal men. CONCLUSIONS: We demonstrated that gonadotrophins act as spermatogonial survival factors via the regulation of intrinsic apoptotic pathway, whereas having no effect of cellular proliferation in normal men.


Subject(s)
Gonadotropins/physiology , Spermatogonia/physiology , Adult , Apoptosis/physiology , Caspase 8/metabolism , Caspase 9/metabolism , Cell Shape , Cell Survival/physiology , Drug Combinations , Enzyme Activation , Gonadotropins/antagonists & inhibitors , Humans , Immunohistochemistry , In Situ Nick-End Labeling , Male , Medroxyprogesterone Acetate/pharmacology , Middle Aged , Reference Values , Spermatids/cytology , Spermatogenesis/physiology , Spermatogonia/cytology , Spermatogonia/enzymology , Testosterone/pharmacology
3.
J Clin Endocrinol Metab ; 91(10): 3962-9, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16895950

ABSTRACT

CONTEXT: Male hormonal contraception via gonadotropin and intratesticular androgen withdrawal disrupts spermatogenesis at two principal sites: 1) spermatogonial maturation, and 2) spermiation. OBJECTIVE: The objective of this study was to explore the relative dependence of each stage of germ cell development on FSH and LH/intratesticular androgen action. DESIGN, SETTING, AND PARTICIPANTS: Eighteen men enrolled in this prospective, randomized 14-wk study at Prince Henry's Institute. INTERVENTIONS: Subjects (n = 6/group) were assigned to 6 wk of 1) testosterone (T) implant (4 x 200 mg sc once)+depot medroxy progesterone acetate (DMPA; 150 mg im once); 2) T implant+DMPA+FSH (300 IU sc twice weekly); and 3) T implant+DMPA+human chorionic gonadotropin (hCG; 1000 IU sc twice weekly as an LH substitute). Men then underwent a vasectomy and testicular biopsy with previously reported control data used for comparison. MAIN OUTCOME MEASURES: Germ cell number (assessed by the optical disector stereological approach) and intratesticular androgen levels were determined. RESULTS: T+DMPA alone significantly suppressed type B spermatogonia, preleptotene through to pachytene spermatocytes, and round spermatids from control (P < 0.05). All germ cell subtypes were maintained at control levels by either FSH or LH activity, except pachytene spermatocytes, which were found to be lower in the hCG vs. FSH (P < 0.01) and control groups (P < 0.05). CONCLUSIONS: FSH and LH maintained spermatogenesis independently in this gonadotropin-suppressed model. Compared with LH, FSH showed better maintenance of pachytene spermatocyte number, whereas improved conversion to round spermatids was suggested with hCG treatment. Future contraceptive treatment strategies must consider independent regulation of spermatogenesis by both FSH and LH/intratesticular androgens for maximum efficacy.


Subject(s)
Follicle Stimulating Hormone/physiology , Luteinizing Hormone/physiology , Spermatogenesis , Spermatogonia/physiology , Adult , Chorionic Gonadotropin/pharmacology , Estradiol/blood , Follicle Stimulating Hormone/blood , Humans , Luteinizing Hormone/blood , Male , Medroxyprogesterone Acetate/administration & dosage , Middle Aged , Prospective Studies , Sperm Count , Testis/chemistry , Testosterone/administration & dosage , Testosterone/blood
4.
Hum Reprod Update ; 12(4): 463-82, 2006.
Article in English | MEDLINE | ID: mdl-16597629

ABSTRACT

Current male hormonal contraceptive (MHC) regimens act at various levels within the hypothalamic pituitary testicular axis, principally to induce the withdrawal of the pituitary gonadotrophins and in turn intratesticular androgen production and spermatogenesis. Azoospermia or severe oligozoospermia result from the inhibition of spermatogonial maturation and sperm release (spermiation). All regimens include an androgen to maintain virilization, while in many the suppression of gonadotrophins/spermatogenesis is augmented by the addition of another anti-gonadotrophic agent (progestin, GnRH antagonist). The suppression of sperm concentration to 1 x 10(6)/ml appears to provide comparable contraceptive efficacy to female hormonal methods, but the confidence intervals around these estimates remain relatively large, reflecting the limited number of exposure years reported. Also, inconsistencies in the rapidity and depth of spermatogenic suppression, potential for secondary escape of sperm into the ejaculate and onset of fertility return not readily explainable by analysis of subject serum hormone levels, germ cell number or intratesticular steroidogenesis, are apparent. As such, a better understanding of the endocrine and genetic regulation of spermatogenesis is necessary and may allow for new treatment paradigms. The development of an effective, consumer-friendly male contraceptive remains challenging, as it requires strong translational cooperation not only between basic scientists and clinicians but also between public and private sectors. At present, a prototype MHC product using a long-acting injectable testosterone and depot progestin is well advanced.


Subject(s)
Contraceptive Agents, Male/pharmacology , Hormones/pharmacology , Spermatogenesis/physiology , Androgens/administration & dosage , Animals , Body Composition/drug effects , Contraceptive Agents, Male/adverse effects , Follicle Stimulating Hormone/metabolism , Gonadotropins/metabolism , Luteinizing Hormone/metabolism , Male , Prostate/drug effects , Spermatogenesis/drug effects , Spermatogenesis-Blocking Agents/pharmacology , Testosterone
5.
J Clin Endocrinol Metab ; 91(3): 1108-11, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16394084

ABSTRACT

CONTEXT: Gonadotropic regulation of the testicular Leydig cell hormone insulin-like factor 3 (INSL3) is incompletely characterized. OBJECTIVE: The objective of this study was to assess the effects of gonadotropin suppression and induced or spontaneous recovery on serum INSL3. DESIGN AND PARTICIPANTS: Serum samples from 15 men enrolled in a short-term study of gonadotropin stimulation, suppression, and recovery and 11 men in a long-term study of gonadotropin suppression and spontaneous recovery were analyzed for INSL3. INTERVENTION: Gonadotropins were suppressed by exogenous testosterone and progestin. Recovery was spontaneous or induced with exogenous gonadotropins. OUTCOME MEASURE: The outcome measure was serum INSL3 in relation to other reproductive hormones. RESULTS: Serum INSL3 was not acutely sensitive to gonadotropins. In both studies, INSL3 declined markedly with gonadotropin suppression (6-13.5% of baseline; P < 0.05). In the short-term study, human chorionic gonadotropin partially restored suppressed serum INSL3 within 4 d of administration (from 7.5 to 38.3% baseline; P < 0.05); the increase correlated with the corresponding increase in serum pro-alphaC (r = 0.82; P < 0.01). FSH did not stimulate the suppressed INSL3. In the long-term study, serum testosterone recovered significantly better (80% baseline) compared with serum INSL3 (38.9% baseline; P < 0.01) in the presence of fully recovered serum LH. CONCLUSIONS: INSL3 is not sensitive to gonadotropin stimulation in normal men, but declines markedly in response to gonadotropin deprivation. After suppression, INSL3 was responsive to hCG 4 d after administration. After long-term suppression, INSL3 did not recover to the same degree as testosterone, suggesting that INSL3 is more sensitive to Leydig cell impairment than testosterone.


Subject(s)
Gonadotropins/antagonists & inhibitors , Gonadotropins/pharmacology , Insulin/metabolism , Proteins/metabolism , Adult , Chorionic Gonadotropin/pharmacology , Follicle Stimulating Hormone/pharmacology , Humans , Insulin/blood , Insulin Secretion , Luteinizing Hormone/blood , Male , Middle Aged , Recombinant Proteins/pharmacology , Reference Values
6.
J Clin Endocrinol Metab ; 90(10): 5647-55, 2005 Oct.
Article in English | MEDLINE | ID: mdl-16030154

ABSTRACT

CONTEXT: Combination of a GnRH antagonist (acyline), types I and II, 5alpha-reductase inhibitor (dutasteride) or levonorgestrel (LNG) with testosterone (T) treatment may augment the suppression of spermatogenesis and intratesticular (iT) steroids. OBJECTIVE: The objective of this study was to assess the effects of combined hormonal contraceptive regimens on germ cell populations and iT steroids. DESIGN, SETTING, AND PARTICIPANTS: Twenty-nine normal health men enrolled in this prospective, randomized, 14-wk study at the University of Washington. INTERVENTION(S): Twenty-two men (n = 5-6/group) received 8 wk of T enanthate (TE; 100 mg, i.m., weekly) combined with 1) 125 microg LNG daily, orally; 2) 125 microg LNG plus 0.5 mg dutasteride daily, orally; 3) 300 microg/kg acyline twice weekly, s.c.; or 4) 125 microg LNG daily, orally, plus 300 microg/kg acyline twice weekly, s.c. Subjects then underwent a vasectomy and testicular biopsy. Control men (n = 7) proceeded directly to surgery. MAIN OUTCOME MEASURE(S): The main outcome measures were germ cells and iT steroids [T, dihydrotestosterone, 3alpha- and beta-androstanediol (Adiol), and estradiol (E2)]. RESULTS: High iT levels of all androgens (6- to 123-fold serum levels) and E2 (407-fold serum levels) were found in control men. iTT (1.9-2.6% control; P < 0.001) and iT3betaAdiol (16-34% control; P < 0.05) levels decreased with all treatments. iT dihydrotestosterone (13-29% control; P < 0.05) and iT3alphaAdiol (44-47% control; P < 0.05) levels decreased with all but the TE plus LNG treatment. iTE2 levels decreased only in the TE plus acyline group (28% control; P = 0.01). Germ cells from type B spermatogonia onward were suppressed, with no differences between groups found. Variable sites of impairment of germ cell progression were evident between men (spermagonial maturation, meiosis 1 entry, and spermiation). Other than a negative correlation between iT3alphaAdiol and haploid germ cell number (P < 0.006), no correlations between germ cell number and gonadotropins, sperm concentration, or iT steroids were found. CONCLUSIONS: A similar high testicular:serum gradient exists for E2 and T in normal men, and 8 wk of gonadotropin suppression markedly reduces iTT, with 5alpha-reduced androgens and E2 levels decreasing to a much lesser degree. The heterogeneity of the germ cell response, regardless of treatment, gonadotropins or iT steroids, points to the individual sensitivity of sites in germ cell development, which is worthy of additional exploration.


Subject(s)
5-alpha Reductase Inhibitors , Enzyme Inhibitors/pharmacology , Gonadotropin-Releasing Hormone/antagonists & inhibitors , Levonorgestrel/pharmacology , Progesterone Congeners/pharmacology , Spermatogenesis/drug effects , Steroids/metabolism , Testis/drug effects , Testis/metabolism , Testosterone/pharmacology , Adult , Androstanes/blood , Azasteroids/pharmacology , Dihydrotestosterone/blood , Dutasteride , Estradiol/blood , Germ Cells/drug effects , Humans , Male , Prospective Studies , Sertoli Cells/drug effects , Testosterone/blood , Vasectomy
7.
J Clin Endocrinol Metab ; 90(1): 91-7, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15509637

ABSTRACT

We postulated that the addition of a combined types I and II, 5alpha-reductase inhibitor (dutasteride) or long-acting GnRH antagonist (acyline) to combination testosterone plus levonorgestrel treatment may be advantageous in the suppression of spermatogenesis for male contraception. This study aimed to examine effects of novel combination contraceptive regimens on serum gonadotropins and androgens and sperm concentration.This study was divided into three phases: screening (2 wk), treatment (8 wk), and recovery (4 wk). Twenty-two men (n = 5-6/group) received 8 wk of treatment with testosterone enanthate (TE, 100 mg im weekly) combined with one of the following: 1) levonorgestrel (LNG) 125 mug orally daily; 2) LNG 125 microg plus dutasteride 0.5 mg orally daily; 3) acyline 300 microg/kg sc every 2 wk (as a comparator for any additional progestin effects); or 4) LNG 125 microg orally daily plus acyline 300 microg/kg sc every 2 wk. Serum gonadotropin levels were similarly suppressed by all treatments, falling to a nadir between 1.2 and 3.4% and 0.5 and 0.8% baseline for FSH and LH, respectively (P < 0.05). Serum dihydrotestosterone levels were significantly (P < 0.05) decreased in the dutasteride group throughout the treatment period to a nadir of 31% baseline (wk 7). No significant differences in sperm concentrations among treatment groups were seen. Severe oligospermia (0.1-3 million/ml) or azoospermia was seen in none of five and four of five in TE + LNG; two of six and four of six in TE + LNG + dutasteride; two of six and four of six in TE + acyline; and one of five and three of five in TE + LNG + acyline groups, respectively. There was one nonresponder in each of the TE + LNG and TE + LNG + acyline groups.We conclude that the addition of a combined types I and II, 5alpha-reductase inhibitor or long-acting GnRH antagonist to a testosterone plus LNG regimen provides no additional suppression of gonadotropins or sperm concentration over an 8-wk treatment period. However, further evaluation of the effects of these regimens on the testis (including testicular steroid levels and germ cell maturation) and the treatment of larger numbers of men (and for longer periods) may provide data to support their place in contraceptive development.


Subject(s)
Cholestenone 5 alpha-Reductase/antagonists & inhibitors , Contraceptive Agents, Male/pharmacology , Gonadotropin-Releasing Hormone/antagonists & inhibitors , Levonorgestrel/administration & dosage , Spermatogenesis/drug effects , Testosterone/administration & dosage , Adult , Humans , Luteinizing Hormone/blood , Male , Middle Aged , Prospective Studies , Sex Hormone-Binding Globulin/analysis , Sperm Count , Testosterone/blood
8.
Hum Reprod ; 18(4): 734-43, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12660264

ABSTRACT

BACKGROUND: Testicular regulation of inhibin B may be influenced by the germ cell complement. METHODS: We examined the effects of gonadotrophin stimulation on serum inhibin B and pro-alphaC in 25 normal men at (i) control (stimulation test 1), (ii) after spermatogenic suppression induced by testosterone plus progestin treatment (stimulation test 2), and (iii) during spermatogenic recovery induced by FSH and/or hCG treatment (stimulation test 3). For each test, subjects received a single injection of 1200 IU FSH or 5000 IU hCG or both. RESULTS: Inhibin B and pro-alphaC fell with spermatogenic suppression (75 and 51% of pre-treatment baseline respectively, P < 0.05). Inhibin B response to FSH (130-144%) was similar in controls and after germ cell suppression. Pro-alphaC response after germ cell suppression compared with control was significantly increased (P < 0.05) with both FSH (210-229% versus 140-185%) and hCG (254-261% versus 145%). All treatments partially restored spermatogenesis with no clear relationship apparent between inhibin B and sperm count. CONCLUSIONS: We conclude that: (i) serum inhibin B and pro-alphaC are only partially gonadotrophin dependent, (ii) spermatogenic suppression does not modify inhibin B response to FSH but enhances pro-alphaC response to both FSH and hCG, and (iii) inhibin B is a poor marker of spermatogenesis in this model of gonadotrophic manipulation in normal men.


Subject(s)
Chorionic Gonadotropin/pharmacology , Contraceptive Agents, Male/pharmacology , Follicle Stimulating Hormone/pharmacology , Inhibins/blood , Protein Precursors/blood , Adult , Biomarkers/blood , Chorionic Gonadotropin/adverse effects , Follicle Stimulating Hormone/adverse effects , Gonadotropins/blood , Humans , Male , Reference Values , Spermatogenesis/physiology , Testosterone/blood
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