Medicinal Use of Testosterone and Related Steroids Revisited.

Testosterone derivatives and related compounds (such as anabolic-androgenic steroids-AAS) are frequently misused by athletes (both professional and amateur) wishing to promote muscle development and strength or to cover AAS misuse. Even though these agents are vastly regarded as abusive material, they have important pharmacological activities that cannot be easily replaced by other drugs and have therapeutic potential in a range of conditions (e.g., wasting syndromes, severe burns, muscle and bone injuries, anemia, hereditary angioedema). Testosterone and related steroids have been in some countries treated as controlled substances, which may affect the availability of these agents for patients who need them for therapeutic reasons in a given country. Although these agents are currently regarded as rather older generation drugs and their use may lead to serious side-effects, they still have medicinal value as androgenic, anabolic, and even anti-androgenic agents. This review summarizes and revisits the medicinal use of compounds based on the structure and biological activity of testosterone, with examples of specific compounds. Additionally, some of the newer androgenic-anabolic compounds are discussed such as selective androgen receptor modulators, the efficacy/adverse-effect profiles of which have not been sufficiently established and which may pose a greater risk than conventional androgenic-anabolic agents.

Reprotoxic activities of vildagliptin administration in male Wistar rats

Vildagliptin is an oral hypoglycemic agent used in the management of diabetes. Some oral antidiabetic drugs have been implicated in reproductive toxicity.The objective of this study was to investigate the effects of daily administration of vildagliptin at different dosages (0.35 mg/kg B.W., 0.70 mg/kg B.W. and 1.40 mg/kg B.W.) to male Wistar rats for 8 weeks. Sperm parameters, serum concentrations of testosterone, follicle stimulating hormone and luteinizing hormone and the histology of the testis of the rats were assessed. Another set of rats were also treated for 8 weeks and allowed to recover and the same parameters were assessed in them. Fertility study was conducted by determining their litter size. The results showed that vildagliptin administration significantly reduced sperm count and motility of the treated rats. It also significantly increased the number of abnormal sperms. Serum level of testosterone was significantly decreased while luteinizing hormone and follicle stimulating hormone levels showed no significant change. The histoarchitecture of the testis of the treated rats appeared visibly normal. The litter size was also significantly reduced. Most of the changes observed were dose dependent. However, these parameters were restored towards normal in the recovery group. Our results suggest that vildagliptin adversely affected sperm parameters, affected litter size and disrupted the pituitary - gonadal axis. These changes were however reversed upon cessation of drug administration.

Identification of candidate reference chemicals for in vitro steroidogenesis assays.

The Endocrine Disruptor Screening Program (EDSP) is transitioning from traditional testing methods to integrating ToxCast/Tox21 in vitro high-throughput screening assays for identifying chemicals with endocrine bioactivity. The ToxCast high-throughput H295R steroidogenesis assay may potentially replace the low-throughput assays currently used in the EDSP Tier 1 battery to detect chemicals that alter the synthesis of androgens and estrogens. Herein, we describe an approach for identifying in vitro candidate reference chemicals that affect the production of androgens and estrogens in models of steroidogenesis. Candidate reference chemicals were identified from a review of H295R and gonad-derived in vitro assays used in methods validation and published in the scientific literature. A total of 29 chemicals affecting androgen and estrogen levels satisfied all criteria for positive reference chemicals, while an additional set of 21 and 15 chemicals partially fulfilled criteria for positive reference chemicals for androgens and estrogens, respectively. The identified chemicals included pesticides, pharmaceuticals, industrial and naturally-occurring chemicals with the capability to increase or decrease the levels of the sex hormones in vitro. Additionally, 14 and 15 compounds were identified as potential negative reference chemicals for effects on androgens and estrogens, respectively. These candidate reference chemicals will be informative for performance-based validation of in vitro steroidogenesis models.

Maintaining physiological testosterone levels by adding dehydroepiandrosterone to combined oral contraceptives: I. Endocrine effects.

OBJECTIVE: To determine whether adding dehydroepiandrosterone to combined oral contraceptives (COCs) maintains physiological levels of free testosterone. STUDY DESIGN: A randomized, double-blind, placebo-controlled, two-way crossover study conducted in 81 healthy women (age range: 20-35 years; Body mass index (BMI) range: 18-35 kg/m2) using oral contraceptives. Androgens, sex hormone-binding globulin (SHBG), estradiol (E2) and estrone (E1) were measured, and free testosterone and the free testosterone index were calculated. Subjects discontinued oral contraceptive use for at least one menstrual cycle before being randomized to receive five cycles of ethinyl estradiol (EE) combined with either levonorgestrel (EE/LNG group) or drospirenone (EE/DRSP group) together with either dehydroepiandrosterone (DHEA) (50 mg/day orally) or placebo. Subsequently, all subjects crossed over to the other treatment arm for an additional five cycles. RESULTS: Both COCs decreased the levels of all androgens measured. Significant decreases (p<.05) were found with EE/LNG and EE/DRSP for total testosterone (54.5% and 11.3%, respectively) and for free testosterone (66.8% and 75.6%, respectively). Adding DHEA to the COCs significantly increased all androgens compared to placebo. Moreover, including DHEA restored free testosterone levels to baseline values in both COC groups and total testosterone levels to baseline in the EE/LNG group and above baseline in the EE/DRSP group. SHBG concentrations were significantly higher with EE/DRSP compared to EE/LNG (p<.0001). The addition of DHEA did not affect the levels of SHBG. CONCLUSIONS: Taking COCs reduces total and free testosterone levels and increases SHBG concentrations. By coadministration with DHEA, physiological levels of total and free testosterone are restored while using EE/LNG. With EE/DRSP, only the free testosterone level is normalized by DHEA coadministration. IMPLICATIONS: A daily oral dose of 50-mg DHEA maintains physiological free and total testosterone levels in women who are using an EE/LNG-containing COC.

Carnitine-mediated antioxidant enzyme activity and Bcl2 expression involves peroxisome proliferator-activated receptor-γ coactivator-1α in mouse testis.

The protective effects of carnitine have been attributed to inhibition of apoptosis, alleviating oxidative stress and DNA repair mechanism by decreasing oxidative radicles. Carnitine also increases mitochondrial biogenesis via peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α). The role of carnitine in testicular PGC1α expression has not been documented. We hypothesised that the effects of carnitine as an antioxidant, inhibitor of apoptosis and controller of steroidogenesis in mouse testis may involve PGC1α as a regulator. The present study was designed to evaluate the localisation of PGC1α and the effects of carnitine treatment on the expression of PGC1α, Bcl2 and antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)) in mouse testis and serum testosterone concentrations. PGC1α was primarily immunolocalised to the Leydig cells and primary spermatocytes. Western blot analysis showed that carnitine (50mgkg-1 and 100mgkg-1 for 7 days) significantly increased PGC1α and Bcl2 expression in the testis in a dose-dependent manner. In addition, carnitine treatment significantly increased antioxidant enzyme (CAT, SOD and GPx) levels. The carnitine-induced changes in PGC1α in the testis were significantly correlated with changes in serum testosterone concentrations, as well as with changes in Bcl2 expression and antioxidant enzyme activity in the testis, as evaluated by electrophoresis. Therefore, the results of the present study suggest that carnitine treatment of mice increases PGC1α levels in the testis, which may, in turn, regulate steroidogenesis by increasing expression of Bcl2 and antioxidant enzymes.

Resveratrol ameliorates benzo(a)pyrene-induced testicular dysfunction and apoptosis: involvement of p38 MAPK/ATF2/iNOS signaling.

Benzo(a)pyrene [B(a)P] is an environmental toxicant that alters the steroidogenic profile of testis and induces testicular dysfunction. In the present study, we have investigated the molecular signaling of B(a)P and the ameliorative potential of the natural aryl hydrocarbon receptor (AhR) antagonist and antioxidant, resveratrol, on B(a)P-induced male reproductive toxicity. Studies showed that B(a)P treatment resulted in p38 MAPK activation and increased inducible nitric oxide synthase (iNOS) production along with testicular apoptosis and steroidogenic dysfunction. Resveratrol cotreatment maintained testicular redox potential, increased serum testosterone level and enhanced expression of major testicular steroidogenic proteins (CYPIIA1, StAR, 3ßHSD, 17ßHSD) and prevented subsequent onset of apoptosis. Resveratrol cotreatment resulted inhibition of testicular cytochrome P4501A1 (CYP1A1) expression, which is the major B(a)P metabolizing agent for BPDE-DNA adduct formation. Resveratrol also significantly decreased the B(a)P-induced AhR protein level, its nuclear translocation and subsequent promoter activation, thereby decreased the expression of CYP1A1. Resveratrol also down-regulated B(a)P-induced testicular iNOS production through suppressing the activation of p38 MAPK and ATF2, thus improved the oxidative status of the testis and prevented apoptosis. Our findings cumulatively suggest that resveratrol inhibits conversion of B(a)P into BPDE by modulating the transcriptional regulation of CYP1A1 and acting as an antioxidant thus prevents B(a)P-induced oxidative stress and testicular apoptosis.

Tadalafil modulates aromatase activity and androgen receptor expression in a human osteoblastic cell in vitro model.

PURPOSE: Phosphodiesterase type-5 inhibitor (PDE5i) tadalafil administration in men with erectile dysfunction is associated with increased testosterone/estradiol ratio, leading to hypothesize a potential increased effect of androgen action on target tissues. We aimed to characterize, in a cellular model system in vitro, the potential modulation of aromatase and sex steroid hormone receptors upon exposure to tadalafil (TAD). METHODS: Human osteoblast-like cells SAOS-2 were chosen as an in vitro model system since osteoblasts are target of steroid hormones. Cells were tested for viability upon TAD exposure, which increased cell proliferation. Then, cells were treated with/without TAD for several times to evaluate potential modulation in PDE5, aromatase (ARO), androgen (AR) and estrogen (ER) receptor expression. RESULTS: Osteoblasts express significant levels of both PDE5 mRNA and protein. Exposure of cells to increasing concentrations of TAD (10(-8)-10(-7) M) decreased PDE5 mRNA and protein expression. Also, TAD inhibited ARO mRNA and protein expression leading to an increase in testosterone levels in the supernatants. Interestingly, TAD increased total AR mRNA and protein expression and decreased ERα, with an increased ratio of AR/ER, suggesting preferential androgenic vs estrogenic pathway activation. CONCLUSIONS: Our results demonstrate for the first time that TAD decreases ARO expression and increases AR protein expression in human SAOS-2, strongly suggesting a new control of steroid hormones pathway by PDE5i. These findings might represent the first evidence of translational actions of PDE5i on AR, which leads to hypothesize a growing relevance of this molecule in men with prostate cancer long-term treated with TAD for sexual rehabilitation.

Restoring testosterone levels by adding dehydroepiandrosterone to a drospirenone containing combined oral contraceptive: I. Endocrine effects.

OBJECTIVES: Combined oral contraceptives (COCs) decrease testosterone (T) levels. This study investigated restoration of T and other androgen concentrations during COC use by 'co-administration' of dehydroepiandrosterone (DHEA). STUDY DESIGN: In this randomized, double-blind, placebo-controlled study in 99 new COC starters (18-35 years old with body mass index range 18-34 kg/m²), a COC containing 30mcg ethinylestradiol (EE) and 3 mg drospirenone (DRSP) was used for 3cycles, followed by 6cycles of the same COC combined with either 50 mg/day DHEA or placebo. Total T, albumin, sex hormone-binding globulin (SHBG), DHEA-sulfate (DHEA-S), Δ4-androstenedione (AD), 3α-androstanediol glucuronide (ADG) and estradiol (E2) were measured, whereas free T and the free T index (FTI) were calculated. Assessments took place at baseline (no COC use), after the run-in period (COC use alone) and during the treatment period (DHEA or placebo). RESULTS: During COC use alone, androgen levels decreased, especially total T by 62% and free T by 86%, and SHBG increased by 243%. Total T increased with DHEA compared to placebo (change from end of run-in period to end of treatment period -- 1.3±1.2 nmol/L vs. 0.0±0.4 nmol/L; p<.0001) -- and was restored to baseline levels. Free T and the FTI increased significantly (p<.0001), but the free T level was still 53% below baseline levels. DHEA-S, AD and ADG increased significantly to levels above baseline (p<.0001 for each). DHEA had no effect on SHBG, albumin and E2. CONCLUSIONS: An EE/DRSP containing COC strongly suppressed endogenous androgen concentrations in all users. The addition of 50 mg DHEA to a COC regimen containing EE/DRSP restored total T to baseline levels, but free T levels were restored by only 47% as most of the T remains bound to SHBG. IMPLICATIONS: When using a COC that increases SHBG considerably, a daily dose of 50 mg DHEA is insufficient to normalize free T levels completely.

Restoring testosterone levels by adding dehydroepiandrosterone to a drospirenone containing combined oral contraceptive: II. Clinical effects.

OBJECTIVES: Combined oral contraceptives (COCs) decrease androgen levels, including testosterone (T), which may be associated with sexual dysfunction and mood complaints in some women. We have shown that 'co-administration' of dehydroepiandrosterone (DHEA) to a drospirenone (DRSP)-containing COC restored total T levels to baseline and free T levels by 47%. Here we describe the effects on sexual function, mood and quality of life of such an intervention. STUDY DESIGN: This was a randomized, double-blind, placebo-controlled study in 99 healthy COC starters. A COC containing 30 mcg ethinylestradiol (EE) and 3 mg DRSP was used for three cycles, followed by six cycles of the same COC combined with 50 mg/day DHEA or placebo. Subjects completed the Moos Menstrual Distress Questionnaire (MDQ), the McCoy Female Sexuality Questionnaire and the short form of the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q). Safety and tolerability, including effects on skin, were evaluated. RESULTS: The addition of DHEA induced small but significant improvements compared to placebo in the MDQ score for autonomic reactions during the menstrual (-2.0 vs. 0.71; p=0.05) and the premenstrual phase (-3.1 vs. 2.9; p=0.01) and for behavior during the intermenstrual phase (-1.4 vs. 3.6; p=0.02). A significant difference was found in the MDQ score for arousal during the premenstrual phase in favor of placebo (-5.0 vs. 1.0; p=0.01). There were no statistically significant differences between groups for the MSFQ and Q-LES-Q scores. DHEA 'co-administration' resulted in an acceptable safety profile. DHEA negated the beneficial effect of the COC on acne according to the subjects' self-assessment. CONCLUSIONS: 'Co-administration' with DHEA did not result in consistent improvements in sexual function, mood and quality of life indicators in women taking EE/DRSP. Retrospectively, the 50 mg dose of DHEA may be too low for this COC. IMPLICATIONS: A well-balanced judgment of the clinical consequences of normalizing androgens during COC use may require complete normalization of free T.

1,25-Dihydroxyvitamin D3 increases testosterone-induced 17beta-estradiol secretion and reverses testosterone-reduced connexin 43 in rat granulosa cells.

BACKGROUND: Aromatase converts testosterone into 17beta-estradiol in granulosa cells, and the converted 17beta-estradiol contributes to follicular maturation. Additionally, excessive testosterone inhibits aromatase activity, which can lead to concerns regarding polycystic ovary syndrome (PCOS). Generally, 1,25-dihydroxyvitamin D3 (1,25D3) supplements help to improve the symptoms of PCOS patients who exhibit low blood levels of 1,25D3. Therefore, this study investigated the interaction effects of 1,25D3 and testosterone on estrogenesis and intercellular connections in rat granulosa cells. METHODS: Primary cultures of granulosa cells were treated with testosterone or testosterone plus 1,25D3, or pre-treated with a calcium channel blocker or calcium chelator. Cell lysates were subjected to western blot analysis to determine protein and phosphorylation levels, and 17beta-estradiol secretion was examined using a radioimmunoassay technique. Cell viability was evaluated by MTT reduction assay. Connexin 43 (Cx43) mRNA and protein expression levels were assessed by qRT-PCR, western blot, and immunocytochemistry. RESULTS: Testosterone treatment (0.1 and 1 microg/mL) increased aromatase expression and 17beta-estradiol secretion, and the addition of 1,25D3 attenuated testosterone (1 microg/mL)-induced aromatase expression but improved testosterone-induced 17beta-estradiol secretion. Furthermore, testosterone-induced aromatase phosphotyrosine levels increased at 10 min, 30 min and 1 h, whereas 1,25D3 increased the longevity of the testosterone effect to 6 h and 24 h. Within 18-24 h of treatment, 1,25D3 markedly enhanced testosterone-induced 17beta-estradiol secretion. Additionally, pre-treatment with a calcium channel blocker nifedipine or an intracellular calcium chelator BAPTA-AM reduced 1,25D3 and testosterone-induced 17beta-estradiol secretion. Groups that underwent testosterone treatment exhibited significantly increased estradiol receptor beta expression levels, which were not affected by 1,25D3. Neither testosterone nor 1,25D3 altered 1,25D3 receptor expression. Finally, at high doses of testosterone, Cx43 protein expression was decreased in granulosa cells, and this effect was reversed by co-treatment with 1,25D3. CONCLUSIONS: These data suggest that 1,25D3 potentially increases testosterone-induced 17beta-estradiol secretion by regulating aromatase phosphotyrosine levels, and calcium increase is involved in both 1,25D3 and testosterone-induced 17beta-estradiol secretion. 1,25D3 reverses the inhibitory effect of testosterone on Cx43 expression in granulosa cells.

Androgenic effect of honeybee drone milk in castrated rats: roles of methyl palmitate and methyl oleate.

ETHNOPHARMACOLOGICAL RELEVANCE: Numerous honeybee (Apis mellifera) products have been used in traditional medicine to treat infertility and to increase vitality in both men and women. Drone milk (DM) is a relatively little-known honeybee product with a putative sexual hormone effect. The oestrogenic effect of a fraction of DM has recently been reported in rats. However, no information is available on the androgenic effects of DM. The purpose of the present study was to determine the androgen-like effect of DM in male rats and to identify effective compounds. MATERIALS AND METHODS: A modified Hershberger assay was used to investigate the androgenic effect of crude DM, and the plasma level of testosterone was measured. The prostatic mRNA and protein expression of Spot14-like androgen-inducible protein (SLAP) were also examined with real-time PCR and Western blot techniques. GC-MS and NMR spectroscopic investigations were performed to identify the active components gained by bioactivity-guided fractionation. RESULTS: The crude DM increased the relative weights of the androgen-dependent organs and the plasma testosterone level in castrated rats and these actions were flutamide-sensitive. DM increased the tissue mRNA and protein level of SLAP, providing further evidence of its androgen-like character. After bioactivity-guided fractionation, two fatty acid esters, methyl palmitate (MP) and methyl oleate (MO), were identified as active compounds. MP alone showed an androgenic effect, whereas MO increased the weight of androgen-sensitive tissues and the plasma testosterone level only in combination. CONCLUSION: The experimental data of DM and its active compounds (MO and MP) show androgenic activity confirming the traditional usage of DM. DM or MP or/and MO treatments may project a natural mode for the therapy of male infertility.

Toxic hepatitis in a group of 20 male body-builders taking dietary supplements.

Dietary supplements have been used for decades for enhancing muscle growth. The harm caused by some of these products is well documented. We investigated and reported toxic hepatitis in 20 male athletes following self-prescribing of a number of dietary supplements which are lesser known. The patients' ages ranged from 24 to 32 with a mean of 28 years. They had taken three kinds of supplements for 1 year including testosterone optimizer agent T Bomb II, a creatine supplement Phosphagen and an amino acid based supplement Cell-Tech. Based on the history, clinical examination, and laboratory findings the cases were diagnosed as toxic hepatitis. After discontinuation of taking the supplements, clinical recovery and improvement of liver function tests were achieved within 30 days. Causality assessment with the CIOMS (Council for International Organization Medical Sciences) scale showed a "possible" grade of causality (+5 points) for these supplements. It can be concluded that these newer anabolic supplements may induce toxic hepatitis. Since the health risks of them may be severe, the use of these kinds of dietary supplements should be discouraged.

Interleukin-6 regulates androgen synthesis in prostate cancer cells.

PURPOSE: The standard systemic treatment for prostate cancer patients is androgen deprivation therapy. Although serum testosterone concentrations were significantly reduced after androgen deprivation therapy, levels of intraprostatic androgens are reproducibly measured at concentrations sufficient to activate androgen receptor and stimulate tumor growth, suggesting that prostate cancer cells may survive androgen deprivation therapies by increasing intracrine androgen synthesis within the prostate. However, factors that regulate de novo intracrine androgen synthesis have not been identified. Interleukin-6 (IL-6) has been implicated in the modulation of androgen receptor activation and growth and differentiation in prostate cancer. In this study, we investigate whether IL-6 regulates intraprostatic androgen synthesis in prostate cancer cells. EXPERIMENTAL DESIGN: Quantitative reverse transcription-PCR and Western blotting were done to detect expression levels of steroidogenic enzymes. AKR1C3 promoter reporter was constructed and analyzed for IL-6-mediated AKR1C3 transcriptional activity. IL-6-mediated signaling was knocked down using small interfering RNA specific to IL-6 receptor and gp130, and the effect on AKR1C3 expression was examined. Intraprostatic androgen levels in prostate cancer cells in culture and in tumors were measured by an enzyme immunoassay (Testosterone EIA kit). RESULTS: We found that IL-6 increases the expression of genes encoding many steroidogenic enzymes, including HSD3B2 and AKR1C3, involved in androgen biosynthesis. Down-regulation of IL-6 receptor and gp130 expression using specific small interfering RNA abolished IL-6-mediated AKR1C3 expression, suggesting that IL-6 signaling is responsible for AKR1C3 expression. IL-6 increases AKR1C3 promoter activity, indicating that the increase in IL-6-mediated AKR1C3 expression is in part at the transcriptional level. Treatment of IL-6 increased testosterone level in LNCaP cells. The tumor testosterone levels were detected at 378 pg/g in tumors generated from IL-6-overexpressing LNCaP-IL6(+) cells inoculated orthotopically into the prostates of castrated male nude mice. CONCLUSIONS: These results suggest that IL-6 increases levels of intracrine androgens through enhanced expression of genes mediating androgen metabolism in prostate cancer cells.

Selective androgen receptor modulators as function promoting therapies.

PURPOSE OF REVIEW: The past decade has witnessed an unprecedented discovery effort to develop selective androgen receptor modulators (SARMs) that improve physical function and bone health without adversely affecting the prostate and cardiovascular outcomes. This review describes the historical evolution, the rationale for SARM development, and the mechanisms of testosterone action and SARM selectivity. RECENT FINDINGS: Although steroidal SARMs have been around since the 1940s, a number of nonsteroidal SARMs that do not serve as substrates for CYP19 aromatase or 5alpha-reductase, act as full agonists in muscle and bone and as partial agonists in prostate are in development. The differing interactions of steroidal and nonsteroidal compounds with androgen receptor (AR) contribute to their unique pharmacologic actions. Ligand binding induces specific conformational changes in the ligand-binding domain, which could modulate surface topology and protein-protein interactions between AR and coregulators, resulting in tissue-specific gene regulation. Preclinical studies have demonstrated the ability of SARMs to increase muscle and bone mass in preclinical rodent models with varying degree of prostate sparing. Phase I trials of SARMs in humans have reported modest increments in fat-free mass. SUMMARY: SARMs hold promise as a new class of function promoting anabolic therapies for a number of clinical indications, including functional limitations associated with aging and chronic disease, frailty, cancer cachexia, and osteoporosis.

Discontinued drugs in 2006: renal, endocrine and metabolic drugs.

This perspective summarizes key compounds from the endocrine and metabolic area that were discontinued from clinical development during the calendar year 2006. This is a continuation in a series of perspectives of each of the editorial areas summarized by Expert Opinion on Investigational Drugs. The candidates covered in this summary were being developed for the treatment of diabetes and obesity, as well as for reproductive and urogenital health issues.

Expression of a single betaalpha chain protein of equine LH/CG in milk of transgenic rabbits and its biological activity.

Equine chorionic gonadotropin (eCG) is a heavily glycosylated glycoprotein composed of non-covalently linked alpha- and beta-subunits. eCG possesses the particularity to bind to both LH and FSH receptors in species other than horses and to have a prolonged plasma half-life. All these properties make it of utmost interest for livestock fertilization program. Up to now, the only source of eCG is the serum of pregnant mare. Rabbit mammary gland is considered as a system able to produce recombinant glycoproteins in sufficient quantity for pharmaceutical use. Here we described the production of a recombinant single betaalpha chain of eLH/CG in the milk of transgenic rabbit. The construction of a single-chain permits to by-pass the problem of association-dissociation of the subunits. This recombinant hormone is greatly expressed (21.7 mg/l) and presents similar in vitro LH and FSH bioactivities. However, betaalphaeLH/CG shows an extremely rapid clearance (approximately 10 min), which could explain the absence of in vivo biological activity. So the rabbit mammary gland is not appropriate for the production of a recombinant active eLH/CG.

Decreased testosterone levels in men with rheumatoid arthritis: effect of low dose prednisone therapy.

OBJECTIVE: To determine whether men with rheumatoid arthritis (RA) have abnormal hypothalamic-pituitary-gonadal axis function and to measure the effects of low dose prednisone therapy in these patients. METHODS: We measured testosterone, follicle stimulating hormone (FSH), and luteinizing hormone (LH) in 36 men aged 38-75 (mean age +/- 1 sd = 62 +/- 10 years) who had longstanding active RA (mean disease duration = 17 +/- 12 years) and in 70 healthy elderly male controls, aged 53-83 (mean age 68 = +/- 6 years). We divided the group with RA into those taking no prednisone (n = 12) and those taking 5 to 10 mg/day of prednisone (n = 24) and analyzed these groups separately to determine whether low doses of prednisone affected testosterone levels. RESULTS: Compared to the healthy controls, patients with RA not taking prednisone had normal testosterone levels but significantly elevated levels of FSH and LH (p < 0.01 for both comparisons). In contrast, patients with RA taking prednisone had significantly lower testosterone levels (p < 0.05), but levels of FSH and LH were only slightly elevated compared to controls. Compared to patients not taking prednisone, patients taking prednisone had lower levels of testosterone, FSH, and LH. CONCLUSION: Male patients with RA who are not taking prednisone have significantly elevated levels of FSH and LH with normal testosterone levels, suggesting a state of compensated partial gonadal failure. Male patients with RA taking low doses of prednisone have lower testosterone and gonadotropin levels, suggesting that prednisone may suppress the hypothalmic-pituitary-testicular axis. Since testosterone affects immune function as well as bone and muscle metabolism, androgen deficiency in some men with RA may predispose these patients to more severe disease and to increased complications of steroid therapy such as myopathy and osteoporosis.

Hormonal regulation of steroidogenic enzyme gene expression in Leydig cells.

In normal mouse Leydig cells, steady state levels of mRNA of CYP11A, 3ß-hydroxysteroid dehydrogenase Δ5- >Δ4-isomerase (3ßHSD), and CYP17 are differentially regulated. There is high basal expression of 3ßHSD and CYP11A mRNA, while expression of CYP17 mRNA is absolutely dependent on cAMP stimulation. cAMP is required for maximal expression of all three enzymes. The expression of CYP11A in normal mouse Leydig cells is repressed by glucocorticoids. Glucocorticoids also repress both basal and cAMP-induced expression of 3ßHSD mRNA, but do not repress the synthesis or mRNA levels of CYP17. cAMP induction of 3ßHSD mRNA can be observed only when aminoglutethimide (AG), an inhibitor of cholesterol metabolism, is added to the Leydig cell cultures. The addition of AG also markedly increases cAMP induction of CYP17 mRNA levels. Addition of testosterone or the androgen agonist, mibolerone, to cAMP plus AG treated cultures reduced 3ßHSD and CYP17 mRNA levels to levels comparable to those observed when cells were treated with cAMP only. These data indicate that testosterone acting via the androgen receptor represses expression of both CYP17 and 3ßHSD. The role of protein synthesis in mediating the cAMP induction of 3ßHSD, CYP17 and CYP11A was examined. The addition of cycloheximide, an inhibitor of protein synthesis, to cAMP treated cultures for 24 h completely suppressed both constitutive and cAMP-induced 3ßHSD mRNA levels. Cycloheximide also repressed cAMP-induced levels of CYP17 to 12% of levels observed in the absence of cycloheximide. In sharp contrast, treatment for 24 h with cycloheximide did not suppress cAMP induction of CYP11A mRNA, but reduced basal levels by approx. 50%. These data indicate that newly synthesized protein(s) are required for cAMP induction of CYP17 and 3ßHSD mRNA levels, but not for CYP11A mRNA. A mouse Cyp17 genomic clone containing the entire coding region plus 10 kb of 5' flanking region has been isolated. Fragments of 5' flanking sequences were subcloned into vectors containing the CAT reporter gene and transfected into MA-10 Leydig cells. Transfected cells were treated with cAMP and expression was determined by measuring CAT activity. A cAMP responsive element was identified in a region between -245 and -346 bp relative to the transcription initiation site of Cyp17. Cotransfection into MA-10 Leydig cells of constructs containing 4.5 kb of Cyp17 5' flanking sequences together with a mouse androgen receptor expression vector demonstrate a dose dependent repression of cAMP-induced Cyp17 transcription by the androgen receptor. Studies with the mouse Cyp11a gene demonstrate that the 5' flanking region of the gene contains sequences between 2.5 and 5 kb that are necessary for expression of mouse Cyp11a in Leydig cells but not in adrenal cells.