Percutaneous absorption of 5 alpha-dihydrotestosterone in man. I. Plasma androgen and gonadotrophin levels in normal adult men after percutaneous administration of 5 alpha-dihydrotestosterone

Dihydrotestosterone: Biochemistry, Physiology, and Clinical Implications of Elevated Blood Levels

Benefits associated with lowered serum DHT levels after 5α-reductase inhibitor (5AR-I) therapy in men have contributed to a misconception that circulating DHT levels are an important stimulus for androgenic action in target tissues (e.g., prostate). Yet evidence from clinical studies indicates that intracellular concentrations of androgens (particularly in androgen-sensitive tissues) are essentially independent of circulating levels. To assess the clinical significance of modest elevations in serum DHT and the DHT/testosterone (T) ratio observed in response to common T replacement therapy, a comprehensive review of the published literature was performed to identify relevant data. Although the primary focus of this review is about DHT in men, we also provide a brief overview of DHT in women. The available published data are limited by the lack of large, well-controlled studies of long duration that are sufficiently powered to expose subtle safety signals. Nonetheless, the preponderance of available clinical data indicates that modest elevations in circulating levels of DHT in response to androgen therapy should not be of concern in clinical practice. Elevated DHT has not been associated with increased risk of prostate disease (e.g., cancer or benign hyperplasia) nor does it appear to have any systemic effects on cardiovascular disease safety parameters (including increased risk of polycythemia) beyond those commonly observed with available T preparations. Well-controlled, long-term studies of transdermal DHT preparations have failed to identify safety signals unique to markedly elevated circulating DHT concentrations or signals materially different from T.

Estrone sulfate (E1S), a prognosis marker for tumor aggressiveness in prostate cancer (PCa)

Seeking insight into the possible role of estrogens in prostate cancer (PCa) evolution, we assayed serum E2, estrone (E1), and estrone sulfate (E1S) in 349 PCa and 100 benign prostatic hyperplasia (BPH) patients, and in 208 control subjects in the same age range (50-74 years). E1 (pmol/L+/-S.D.) and E1S (nmol/L+/-S.D.) in the PCa and BPH patients (respectively 126.1+/-66.1 and 2.82+/-1.78, and 127.8+/-56.4 and 2.78+/-2.12) were significantly higher than in the controls (113.8+/-47.6 and 2.11+/-0.96). E2 was not significantly different among the PCa, BPH, and control groups. These assays were also carried out in PCa patients after partition by prognosis (PSA, Gleason score (GS), histological stage, and surgical margins (SM)). Significantly higher E1S levels were found in PCa with: PSA>10 ng/L (3.05+/-1.92) versus PSA<or=10 ng/mL (2.60+/-1.55), stage pT3-T4 (2.99+/-1.80) versus pT2 (2.58+/-1.58), and positive (3.26+/-1.95) versus negative margins (2.52+/-1.48). E1 was higher in poor- than in better-prognosis PCa. E2 was significantly higher in PCa with GS>or=4+3 (109.5+/-43.8) versus GS<or=3+4 (100.6+/-36.5) and increased significantly when GS increased from 3+3 to 4+4. Estrogens, especially E1S appeared to be possible markers of PCa progression. Attempting to identify potential sources of E2 in PCa according to prognosis, as well as in BPH, we found a significant correlation coefficient between E1S and E2 (0.266-0.347) in poor-prognosis PCa and no correlation in BPH (0.026) and better-prognosis PCa (0.013-0.104). It is as though during progression of PCa from good to poor prognosis there were a shift in the E1 to E2 metabolic pathway from predominantly oxidative to predominantly reductive.

Cyproterone Acetate Loading to Lipid Nanoparticles for Topical Acne Treatment: Particle Characterisation and Skin Uptake

PURPOSE

Topical cyproterone acetate (CPA) treatment of skin diseases should reduce side effects currently excluding the use in males and demanding contraceptive measures in females. To improve skin penetration of the poorly absorbed drug, we intended to identify the active moiety and to load it to particulate carrier systems.

MATERIALS AND METHODS

CPA metabolism in human fibroblasts, keratinocytes and a sebocyte cell line as well as androgen receptor affinity of native CPA and the hydrolysis product cyproterone were determined. CPA 0.05% loaded solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC), a nanoemulsion and micropheres were characterized for drug-particle interaction and CPA absorption using human skin ex-vivo.

RESULTS

Native CPA proved to be the active agent. Application of CPA attached to SLN increased skin penetration at least four-fold over the uptake from cream and nanoemulsion. Incorporation into the lipid matrix of NLC and microspheres resulted in a 2-3-fold increase in CPA absorption. Drug amounts within the dermis were low with all preparations. No difference was seen in the penetration into intact and stripped skin.

CONCLUSION

With particulate systems topical CPA treatment may be an additional therapeutic option for acne and other diseases of the pilosebaceous unit.

Male hypogonadism : an update on diagnosis and treatment

Male hypogonadism is one of the most common endocrinologic syndromes. The diagnosis is based on clinical signs and symptoms plus laboratory confirmation via the measurement of low morning testosterone levels on two different occasions. Serum luteinizing hormone and follicle-stimulating hormone levels distinguish between primary (hypergonadotropic) and secondary (hypogonadotropic) hypogonadism. Hypogonadism associated with aging (andropause) may present a mixed picture, with low testosterone levels and low to low-normal gonadotropin levels. Androgen replacement therapy in hypogonadal men has many potential benefits: improved sexual function, an enhanced sense of well-being, increased lean body mass, decreased body fat, and increased bone density. However, it also carries potential risks, including the possibility of stimulating the growth of an occult prostate cancer. The benefits of androgen therapy outweigh the risks in men with classic hypogonadism. However, for men with mild hypogonadism or andropause, the balance between benefits and risks is not always clear. Unfortunately, studies to date have included too small a number of patients and have been too short in duration to provide meaningful data on the long-term risks versus the benefits of androgen replacement therapy in these populations. Several products are currently marketed for the treatment of male hypogonadism. Weekly-to-biweekly injections of testosterone cypionate (cipionate) or testosterone enanthate (enantate) are widely used, as they are economical and generally well tolerated. However, once-daily transdermal therapies have become increasingly popular and now include both patch and gel systems. Intramuscular injection of testosterone undecanoate is an attractive new therapy that can be administered quarterly. To confirm an adequate replacement dosage, assessment of clinical responses and measurement of serum testosterone levels generally suffice. For selected men, serial measurement of bone mineral density during androgen therapy might be helpful to confirm end-organ effects. For men aged >50 years, we advocate measurement of hematocrit for detection of polycythemia and a digital rectal examination with a serum prostate-specific antigen level measurement for prostate cancer screening during the first few months of androgen therapy. Subsequently, a hematocrit should be obtained yearly or after changes in therapy, and annual prostate cancer screening can be offered to the patient after a discussion of its risks and benefits.

Combination of subcutaneous levonorgestrel implants and transdermal dihydrotestosterone gel for male hormonal contraception

The primary aim of the present study was to determine the therapeutic dose of subcutaneous levonorgestrel (LNG) to induce azoospermia or severe oligozoospermia (<3 x 10(6)/mL) in normal men requiring contraception. Transdermal 5 alpha-dihydrotestosterone (DHT) was combined to the treatments to maintain peripheral androgen level. Forty-three 21-45-year-old healthy men were enrolled in this phase II randomised and comparative clinical performance study. The subjects were allocated to five groups to receive: (1) transdermal DHT (Andractim(R), Besins Iscovesco, Paris, France) and one subdermal LNG implant (Jadelle, Leiras, Turku, Finland); (2) transdermal DHT and two subdermal LNG implants; (3) transdermal DHT and four subdermal LNG implants; (4) transdermal DHT and oral LNG (Microluton, Schering, Germany); or (5) transdermal DHT only. A total of 27 men completed the suppression phase. None of them reached azoospermia. One subject with oral LNG and transdermal DHT reached <3 million/mL at 5 months of suppression, but not repeatedly. Together 2/27 (7%) subjects, one with oral LNG and DHT and the other with four subdermal LNG implants and DHT reached <5 million/mL temporarily. Altogether 9/27 (33%) subjects reached <20 million/mL. Serum testosterone concentrations (S-T) decreased significantly during the first 3 months of treatment with one, two and four LNG implants and DHT and during the next 3 months S-T remained significantly lower with two or four implants. Serum oestradiol concentrations (S-E(2)) decreased significantly during the first 3 months only with four implants, but at 6 months S-E(2) was lower also in the group with two implants. Serum luteinizing hormone (LH) decreased significantly only with two LNG implants and DHT gel at 5 and 6 months. Serum FSH did not decrease in any of the groups. None of the subjects filled the criteria to continue to the efficacy phase. A total of 16 men discontinued for various reasons. Of the 27 men completing the suppression phase, all have recovered to sperm levels >20 million/mL. There were no changes in blood count, lipid profile, liver function tests, prostate-specific antigen (PSA), sex hormone binding globulin (SHBG), prolactin or cortisol. The mixed antiglobulin reaction (MAR)-IgG, MAR-IgA or tray agglutination test (TAT) did not change during any of the treatments. The present study shows that the LNG implants themselves are well-tolerated by men and safe, and might be suitable for replacing part of the testosterone used as injections to reduce the androgen dose during male hormonal contraception. The DHT gel was considered as quite or very uncomfortable by 66% of the men because of feeling cold during the time it was on the skin, but noncompliance in using the gel was not reported by the men.

Comparative pharmacokinetics of three doses of percutaneous dihydrotestosterone gel in healthy elderly men--a clinical research center study

Twenty-five men, 60-80 yr old, participated in a pharmacokinetic study to compare three doses (16, 32, and 64 mg/day, n = 8 or 9 in each group) of 5alpha-dihydrotestosterone (DHT) gel (0.7% hydroalcoholic gel with 2.3 g gel delivering 16 mg DHT) applied daily over one upper arm (16 mg); both arms and shoulders (32 mg); and bilateral arms, shoulders, and upper abdomen (64 mg), respectively. Multiple blood samples for the pharmacokinetic profile for DHT and testosterone (T) were drawn over a 24-h period before application, after first application, and after 14 days of daily application of DHT gel. Additional blood samples for DHT, T, and estradiol were obtained 24 h after application on days 3, 5, 7, and 11 and after discontinuation of DHT gel for 3, 5, 7, and 14 days (days 17, 19, 21, and 28 after first instituting treatment). No skin irritation was observed in any of the subjects. Before treatment, mean serum DHT and T levels were not different among the three dose groups. The serum DHT levels increased gradually after gel application on the first day, reaching a plateau between 12-18 h. During the 14 days of daily application of DHT gel, the mean baseline DHT levels reached steady state by day 2 or 3 and were elevated considerably above baseline. Mean serum DHT levels varied between 8-11, 12-17, and 14-24 nmol/L in the 16-, 32-, and 64-mg groups, respectively. The area under curve (AUC) of serum DHT levels over 24 h on day 14 were 6.0-, 6.9-, and 16.1-fold above pretreatment levels for the three doses. Concomitant with the increase in serum DHT levels, the AUC produced by endogenous serum T levels decreased to 75, 56, and 36% of baseline after 14 days of 16, 32, and 64 mg/day DHT gel. Similar patterns of decreases in AUC of serum estradiol levels were found. The calculated mean total androgen levels (T + DHT) rose with DHT gel application in all groups (P < 0.0001) on both days 1 and 14. We conclude that the three doses of DHT gel tested might provide adequate androgen replacement in hypogonadal men at the low, middle, and high physiological androgen (T + DHT) range.

Effect of percutaneous androgen replacement therapy on body composition and body weight in postmenopausal women

OBJECTIVES

This study was carried out to assess the effect of topical androgen replacement therapy on body weight, body composition and fat distribution in postmenopausal women.

METHODS

39 healthy postmenopausal women (51.4 +/- 2.24 years), with increasing body weight, were prospectively studied for 6 months. Body composition (fat mass, kg, %) was measured by means of dual-energy X-ray absorptiometry (DXA). Hormonal and lipid parameters were also measured. Subjects were divided into two groups. An androgen gel (group A) or placebo gel (group P) was topically administered to the abdominal and gluteo-femoral regions. DXA was performed before commencement of topical treatment and after 6 months.

RESULTS

A highly significant total body weight reduction was found in group A (68.0 +/- 13.1 to 65.4 +/- 11.8 kg). Abdominal fat (37.3 +/- 11.2 to 35.1 +/- 9.7%), gluteo-femoral fat (46.3 +/- 6.6 to 45.4 +/- 7.7%), total body fat (38.2 +/- 7.9 to 36.1 +/- 8.6%) and BMI (24.8 +/- 4.3 to 23.7 +/- 3.8) were also found to have decreased significantly in this group. No significant reduction in body weight (kg) and body fat (%) could be measured in the placebo group. No influence on lipid parameters was found although total testosterone increased significantly in group A (0.29 +/- 0.24 to 0.72 +/- 0.17 ng/ml).

CONCLUSIONS

Topically applied androgen is capable of reducing abdominal fat accumulations as well as total body weight in postmenopausal women with unexplained weight gain. In contrast to systemic androgen application, topical administration has no effect on the lipid profile. Gluteal fat, however, is less effectively influenced by androgens.

A multivariate approach to the description of patient populations. An example of the analysis of the hormone profiles of patients with advanced prostate cancer

In view of the multifactorial nature of the endocrine dysfunctions that may develop during prostate cancer and the unsuitability of the most widely used statistical methods to study such dysfunction, we have in the present study examined the relationships among 17 biological variables in 26 patients with advanced prostate cancer by two complementary multivariate methods, correspondence factorial analysis (CFA) and a hierarchical automatic classification procedure. The 17 variables included 14 hormones, their precursors or metabolites [LH, FSH, estradiol (E2), testosterone, dihydrotestosterone (DHT), androstenedione (A), androstenediol (Ediol), dehydroepiandrosterone (DHA), DHA-sulphate (DS), cortisol (CORT), 17 alpha-hydroxyprogesterone (17-OH-PROG), pregnenolone (PREG), 17 alpha-hydroxypregnenolone (17-OH-PREG), and androstanediol glucuronide (ADG)], one plasma binding protein, namely, sex-hormone-binding protein (SHBG) and two tumour markers, prostatic acid phosphatase (PAP) and prostate-specific antigen (PSA). The originality of these multivariate methods is that they do not preselect a dependent variable nor perform two-by-two correlations as in stepwise multiple regression analysis but describe the patient population by extracting layers of correlations (from strong to weak) from amid confounding variables. Compared to principal component analysis which is based on covariance, CFA, based on the chi 2-metric, enables the licit representation of both tests and patients on the same factorial maps. From an examination of proximity among variables, it is possible to deduce which tests are related, which groups of patients have similar hormone profiles, and which tests vary most in which patients. The most discriminant factors in this particular population of patients were PSA and PAP levels, which were, however, not strongly correlated and were apparently selectively associated with certain hormones. PAP seemed the more pathological marker; PSA was somewhat anticorrelated to the adrenal androgen (DHA and DS) and PREG levels. The hormones with the lowest variance were A, Ediol and CORT reflecting their key roles in metabolism. A number of patients were hypogonadic. SHBG levels were not closely related to total T levels but anticorrelated with ADG suggesting that, in the patients concerned, SHBG decreases the bioavailable T fraction. There was no correlation between ADG and precursor hormones (PREG, DHA, DS) but a slight anticorrelation between these precursors and DHT. Therefore the source of ADG in these patients does not seem to be increased levels of precursor hormones nor of DHT but increased peripheral tissue metabolism of androgens. In future, descriptive multivariate analyses of large patient cohorts should help to define subpopulations with distinctive hormone profiles for prospective clinical studies.

Multivariate analysis of plasma hormones in patients with metastatic prostate cancer receiving combined LHRH-analog and antiandrogen therapy

The following hormones, the plasma protein SHBG, and the tumor markers prostatic acid phosphatase (PAP) and prostate-specific antigen (PSA) were assayed at 18 time-points over 1 month during a double-blind randomized study in 36 stage D2 cancer patients receiving either "buserelin+placebo" or "buserelin+nilutamide (Anandron)": LH, FSH, estradiol, testosterone, dihydrotestosterone, androstenedione, 5-androstene-3,17 beta-diol, dehydroepiandrosterone and its sulfate, cortisol, 17 alpha-hydroxyprogesterone, pregnenolone, 17 alpha-hydroxypregnenolone, and 3 alpha-androstanediol glucuronide. Multivariate analysis of the treatment values (over 10,000 assays) by two complementary methods, correspondence factorial analysis (CFA) and the minimum spanning tree (MST) method, identified those variables within the pathways of androgen metabolism that were correlated over time and, in a comparison of the two treatment groups, identified the enzyme targets of nilutamide action in humans. Whereas nilutamide tended to decrease androstenedione slightly, it affected no other variables including cortisol, except for pregnenolone, 17 alpha-OH-pregnenolone, and 17 alpha-OH-progesterone, which were increased. These increases are indicative of weak inhibition of C17,20 lyase by nilutamide, but, according to the multivariate analysis, are insufficient to account for the more marked and rapid fall in PAP and PSA noted on addition of nilutamide to buserelin that must therefore be explained by another mechanism such as androgen receptor blockade by nilutamide.

Increase in plasma 5 alpha-androstane-3 alpha,17 beta-diol glucuronide as a marker of peripheral androgen action in hirsutism: a side-effect induced by cyclosporine A

Dose-dependent hypertrichosis is a common dermatological side-effect affecting the majority of patients treated with cyclosporine A (CSA). Previous studies have not demonstrated the influence of CSA on specific sex hormone levels. The aim of this study is to investigate whether CSA increases the activity of 5 alpha-reductase, an enzyme which transforms androgens into dihydrotestosterone in peripheral tissues. The metabolite which best reflects this activity is 5 alpha-androstane-3 alpha,17 beta-diol glucuronide (Adiol G). The study was carried out on 49 insulin-dependent diabetes patients participating in the double-blind "Cyclosporine-Diabète-France" clinical trial, of which 28 were treated with CSA (16 males and 12 females), and 21 received only placebo (10 males and 11 females). All patients underwent extensive clinical and laboratory evaluations prior to and during the present study. In addition to Adiol G, testosterone (T), dehydroepiandrosterone sulfate (DHEA S) and sex hormone-binding globulin (SHBG) were assayed. Levels of Adiol G increased significantly in CSA-treated groups: males, 11.86 +/- 2.58 vs 7.83 +/- 2.30 nmol/l; females, 4.48 +/- 2.70 vs 2.10 +/- 1.22 nmol/l; P less than 0.02 (comparison of means). There were no significant differences in this parameter before and during treatment in either the male or female placebo groups (paired t-test). During the treatment period, T, DHEA S, SHBG and the T/SHBG ratio did not significantly change with respect to their baseline values in any of the groups studied (comparison of means). Comparison (using paired t-test) showed a significant increase of DHEA S in CSA-treated groups: males, delta = 3.08 +/- 3.33 nmol/l, P less than 0.01; females, delta = 0.98 +/- 1.13 nmol/l, P less than 0.05. In conclusion, it is possible that CSA induces hypertrichosis or hirsutism by increasing 5 alpha-reductase activity in peripheral tissues. Nevertheless the role of increased DHEA S as a possible Adiol G precursor cannot be excluded.

Inhibition of spermatogenesis in men using various combinations of oral progestagens and percutaneous or oral androgens

Eight men (experiment 1) requesting male contraception received a daily oral dose of 20 mg medroxyprogesterone acetate (MPA) combined with 125 mg percutaneous dihydrotestosterone (DHT). Three months later the mean sperm count was only diminished slightly; the replacement of DHT for four men by percutaneous testosterone at the same concentration led to a dramatic fall in sperm count. For 6-18 months all men were treated with MPA plus percutaneous testosterone (250 mg daily). The latter dose restored physiological levels of plasma testosterone. Follicle-stimulating hormone levels were inhibited more severely than in the DHT-treated group, whereas LH levels were variable. Azoospermia was achieved and maintained in six cases; two men were oligozoospermic and in one case a moderate secondary rise in the sperm count was observed. Twelve volunteers (experiment 2) received a daily oral dose of either 5 or 10 mg norethisterone acetate plus percutaneous testosterone (250 mg daily). All of them achieved azoospermia within 2 months, but two subjects later exhibited a partial restoration in sperm count. Follicle-stimulating hormone and LH levels were inhibited more severely than in the first experiment. The sperm count and gonadotrophin levels returned to initial values within 6 months after cessation of the treatment in both experiments. No side-effects were noted concerning blood parameters, libido or body weight. However, several female partners had elevated levels of plasma testosterone. In experiment 3 (13 volunteers), percutaneous testosterone was replaced by oral testosterone undecanoate (160 mg daily). Only seven men were azoospermic and most of them had lowered levels of plasma testosterone. Thus, the combination of percutaneous testosterone and oral progestagens appears to be the most convenient for male hormonal contraception.

Studies on the treatment of idiopathic gynaecomastia with percutaneous dihydrotestosterone

We have studied clinical and endocrine parameters in a group (group A) of forth men referred to us because of persistent idiopathic gynaecomastia (of more than 18 months duration), before and during the administration of percutaneous dihydrotestosterone (DHT). The endocrine parameters (testosterone (T), 17 beta-oestradiol (E2), DHT, gonadotrophins (FSH and LH) and prolactin (PRL), were compared to those of control groups of 12 healthy men on DHT therapy (group B) and 10 on placebo (group C). Local administration of DHT was followed by the complete disappearance of gynaecomastia in 10 patients, partial regression in 19 and no change in 11 patients after 4 to 20 weeks of percutaneous DHT (125 mg twice daily). Before treatment the T + DHT/E2 ratio was significantly (P less than 0.001) lower in group A 244 +/- 21 (SEM) than in groups B and C (361 +/- 21) while T, DHT and E2 concentrations were all within the normal range. During DHT treatment plasma hormone levels were measured in 26 patients from group A: DHT levels increases significantly (day 0: 1.63 +/- 0.14 nmol/l; day 15: 12.8 +/- 1.6 nmol/l, P less than 0.001) while T and E2 levels fell significantly (T: day 0: 22.6 +/- 1.2 nmol/l; day 15: 11.0 +/- 1.5 nmol/l, P less than 0.001; E2: day 0: 110.5 +/- 7.12 pmol/l; day 15: 86.79 +/- 9.4 pmol/l, P less than 0.01). The T/E2 ratio decreased from 231 +/- 20 to 164 +/- 27 (P less than 0.05) while the T + DHT/E2 ratio increased significantly (P less than 0.02) to a normal mean value (day 15: 354 +/- 57).(ABSTRACT TRUNCATED AT 250 WORDS)

Percutaneous absorption of 5 alpha-dihydrotestosterone in man. II. Percutaneous administration of 5 alpha-dihydrotestosterone in hypogonadal men with idiopathic haemochromatosis; clinical, metabolic and hormonal effectiveness

The particularities of percutaneous absorption of a natural androgen, 5 alpha-dihydrotestosterone, were evaluated in substitutive androgen therapy in masculine hypogonadism. Nine men presenting idiopathic haemochromatosis complicated by severe hypogonadism were treated with percutaneous administration of 5 alpha-dihydrotestosterone (125 mg/day) for 5 months. Plasma levels of 5 alpha-dihydrotestosterone and 5 alpha-androstane-3 alpha, 17 beta-diol are greatly increased by treatment (from 0.86 to 18.39 nmol/l and 0.16 to 3.40 nmol/l, respectively). There is no modification of testosterone and oestradiol-17 beta. Double blind study demonstrated the direct stimulating effect of 5 alpha-dihydrotestosterone on sexual behaviour and psychism. Hepatic and metabolic tolerance was excellent in these patients, despite the preceding deleterious effects of the iron excess. The percutaneous route is original, practical and improves the androgen therapy of hypogonadism in men.