Dexamethasone suppresses sex-hormone binding globulin**Supported by the National Institutes of Health, grant 1S0RR08244-01, Bethesda, Maryland; and by the Reproductive Endocrine Laboratory, Department of Obstetrics and Gynecology, Howard University College of Medicine, Washington, D.C

Rapid recovery of hypogonadism in male patients with end stage renal disease after renal transplantation

PURPOSE

End stage renal disease (ESRD) in male patients is associated with a high prevalence of hypogonadism. After renal transplantation (RTx) an improvement in gonadal function is often observed. However, the time course of changes in pituitary-gonadal axis after RTx and the influence of renal function, age and anthropometric parameters are not well characterized. We prospectively evaluated pituitary-gonadal axis in male patients with ESRD before and after RTx for up to 1 year.

METHODS

Ninety-seven male patients with ESRD were consecutively investigated on day of surgery and 1, 3, 6, and 12 months after RTx. Time course of changes in sex hormones (total testosterone ((TT)), calculated free testosterone ((cfT)), estradiol (E₂), LH, FSH and prolactin), and interdependence with renal function, age, anthropometric factors, cause of ERDS, time on dialysis, and transplant associated factors were analyzed.

RESULTS

Hypogonadism (TT < 8 nmol/l) was present in 40% of pts prior to RTX and in only 18% at 1 year after RTX. Recovery from hypogonadism was significantly higher in pts < 50 years and occurred within 3 months. RTx resulted in a decrease in E₂/T ratio starting at 1 month and suggesting a shift from estrogen to testosterone production. BMI and waist circumference had the similar impact on T levels after successful RTx compared to patients without renal disease. No specific impact on recovery of hypogonadism was found for time on dialysis prior to RTx and living or cadaver transplantation.

CONCLUSIONS

Successful RTx is associated with a rapid recovery from hypogonadism within 3 months preceeded by improvement in renal function particularly in patients younger than 50 years.

Advances in the epidemiology, pathogenesis, and management of Cushing's syndrome complications

Cushing's syndrome (CS) is a clinical condition resulting from chronic exposure to glucocorticoid excess. As a consequence, hypercortisolism contributes significantly to the early development of systemic disorders by direct and/or indirect effects. Complications such as obesity, hypertension, diabetes, dyslipidemia, and hypercoagulability cause premature atherosclerosis and increase cardiovascular mortality. Impairment of the skeletal system is a relevant cause of morbidity and disability in these patients especially due to the high prevalence of vertebral fractures. In addition, muscle weakness, emotional lability, depression, and impairment of quality of life are very common. Clinical management of these patients is complex and should be particularly careful in identifying global cardiovascular risks and aim at controlling all complications. Although the primary goal in the prevention and treatment of complications is the correction of hypercortisolism, treatment does not completely eliminate these comorbidities. Given that cardiovascular risk and fracture risk can persist after cure, early detection of each morbidity could prevent the development of irreversible damage. In this review we present the various complications of CS and their pathogenetic mechanisms. We also suggest the clinical management of these patients based on our extensive clinical experience and on the available literature.

Sex hormone-binding globulin gene expression in the liver: drugs and the metabolic syndrome

Sex hormone-binding globulin (SHBG) is the main transport binding protein for sex steroid hormones in plasma and regulates their accessibility to target cells. Plasma SHBG is secreted by the liver under the control of hormones and nutritional factors. In the human hepatoma cell line (HepG2), thyroid and estrogenic hormones, and a variety of drugs including the antioestrogen tamoxifen, the phytoestrogen, genistein and mitotane (Op'DDD) increase SHBG production and SHBG gene promoter activity. In contrast, monosaccharides (glucose or fructose) effectively decrease SHBG expression by inducing lipogenesis, which reduces hepatic HNF-4alpha levels, a transcription factor that play a critical role in controlling the SHBG promoter. Interestingly, diminishing hepatic lipogenesis and free fatty acid liver biosynthesis also appear to be associated with the positive effects of thyroid hormones and PPARgamma antagonists on SHBG expression. This mechanism provides a biological explanation for why SHBG is a sensitive biomarker of insulin resistance and the metabolic syndrome, and why low plasma SHBG levels are a risk factor for developing hyperglycemia and type 2 diabetes, especially in women. These important advances in our knowledge of the regulation of SHBG expression in the liver open new approaches for identifying and preventing metabolic disorder-associated diseases early in life.

Male hypogonadism in cirrhosis and after liver transplantation

Liver is deeply involved in the metabolism of proteins, hormones, enzymes, cytokines, as well as in sex hormones catabolism. Gonadal function requires a normal liver function, and it is well known that clinical signs of hypogonadism are common in patients with liver cirrhosis. Few studies have focused on hypothalamic- pituitary-gonadal alterations in male cirrhotic patients or after orthotopic liver transplantation (OLT). The pathogenesis of hypogonadism in cirrhotic patients is complex and not well explained. It involves both a gonadal and a hypothalamic- pituitary dysfunction. After OLT the hypothalamic-pituitary-gonadal function partially improves, showing that the hepatic dysfunction before OLT is deeply involved in its pathogenesis. After OLT some alterations persist in some patients, both because of pre-existing gonadal alterations (toxic-metabolic damage) and immunosuppressive pharmacological side effects. Further studies will explain the relationship between hypogonadism and OLT outcome, and the role of androgen therapy in hypogonadism after OLT, in the early months and in the long term.

Free Androgen Index Is Superior to Total Testosterone for Short-Term Assessment of the Gonadal Axis after Renal Transplantation

OBJECTIVE

Recent studies have assessed gonadal function in association with different immunosuppressive drugs in transplanted patients mainly relying on the measurement of total testosterone. It is the aim of this study to assess the short-term changes of the hypothalamic-pituitary-gonadal axis following renal transplantation using the free androgen index (FAI).

PATIENTS AND METHODS

The sequential changes in total testosterone, sex hormone-binding globulin (SHBG), gonadotropin and prolactin concentrations were measured in 22 male patients before and after 1-3 days, and 1, 2 and 3 weeks following renal transplantation.

RESULTS

Total testosterone and SHBG concentrations dropped significantly after transplantation (total testosterone: baseline: 15.2 +/- 1.6 nmol/l vs. 1 week: 7.9 +/- 0.8 nmol/l vs. 2 weeks: 9.8 +/- 0.9 nmol/l, SHBG: baseline: 29.9 +/- 3.2 nmol/l vs. 1 week: 19.9 +/- 2.1 nmol/l, 2 weeks: 18.9 +/- 2.4 nmol/l, p < 0.01). FAI decreased significantly after day 1-3 returning to values near baseline thereafter (baseline: 60 +/- 9% vs. day 1-3: 38 +/- 6%, 2 weeks: 61 +/- 7%; p < 0.01). There was a significant positive correlation between FAI and renal function.

CONCLUSION

Measurement of the free androgen index is superior to total testosterone for assessment of the pituitary-gonadal axis in the first weeks after renal transplantation.

Short-term effects of prednisolone and dexamethasone on circulating concentrations of leptin and sex hormone-binding globulin in children being treated for acute lymphoblastic leukaemia

OBJECTIVE

Disturbances in body weight regulation are often encountered during glucocorticoid treatment and are associated with increased insulin resistance and truncal fat accumulation. Children were investigated who were receiving glucocorticoid treatment for acute lymphoblastic leukaemia (ALL). They were randomized to receive either prednisolone or dexamethasone as part of induction of remission. This randomization process provided a suitable opportunity to compare the effects of these two administered steroid on surrogate markers of adipocyte activity (leptin) and hyperinsulinaemia/insulin resistance (SHBG).

DESIGN AND PATIENTS

Prospective study over 16 weeks of children randomized to receive prednisolone (40 mg/m2) or dexamethasone (6.5 mg/m2) as part of the MRC-ALL97/99 induction chemotherapy for ALL. Nineteen children (8 male, 11 female) with a median age 5.9 years (range 2.6-13 years) were recruited into the study. Main outcome measures were body mass index (BMI), serum leptin and sex hormone binding globulin (SHBG).

RESULTS

Glucocorticoid administration for 5 weeks resulted in significant (P < 0.05) increases in BMI, leptin (corrected for BMI) and the leptin : SHBG ratio and lowering of SHBG. Dose for dose, dexamethasone was significantly more potent than prednisolone in altering these parameters.

CONCLUSIONS

Short-term glucocorticoid treatment has significant effects on BMI, leptin and SHBG. The leptin : SHBG ratio increase indicates that this may be a novel and sensitive biochemical marker of metabolic change. Our results suggest that glucocorticoid treatment regimens should be kept as short as possible to avoid possible detrimental effects associated with increased adiposity and insulin resistance.

The effect of long-term glucocorticoid therapy on glucocorticoid receptor content and on steroid response to ACTH

The effect of long-term glucocorticoid therapy for systemic diseases on glucocorticoid receptor (GR) content and on basal and ACTH-stimulated levels of plasma and salivary cortisol 17 alpha-hydroxy-progesterone, androstenedione, 11 beta-hydroxyandrostenedione, DHEA, its sulfate and sex hormone-binding globulin (SHBG), as well as on basal levels of aldosterone, was investigated in a group of 24 children treated with prednisone for at least 8 months. The therapy was interrupted 24 h before the ACTH test and before plasma and saliva sampling. The control group consisted of 21 healthy children of corresponding age and sex. The patients were divided into two subgroups with normal and subnormal basal cortisolemia, they also differed in their response to ACTH. The GR levels in patient groups were indistinguishable from those found in controls. No correlation was found between GR content and basal levels of the above steroids or their response to ACTH. The best markers, apart from basal cortisolemia, for evaluation of the degree of suppression of adrenal function appeared to be the response of salivary (but not of plasma) cortisol and 17 alpha-hydroxy-progesterone to ACTH. Surprisingly, significantly lower levels of SHBG levels, which rose markedly after ACTH, were found in all the patients.

Structure, function, and regulation of androgen-binding protein/sex hormone-binding globulin

Despite over 20 years of research, the functions of ABP and SHBG remain elusive. The major reason for this lack of knowledge has been the unavailability of natural mutants with clinical defects for study. There is strong evidence that these binding proteins do act to modulate the gene regulatory actions of nuclear sex steroid receptors by controlling the availability of androgens and estrogens. In plasma, SHBG controls the metabolic clearance rate of sex steroids. In addition there is strong evidence that they have a much broader function. The identification of plasma membrane receptors in target tissues and the finding of homologous domains in several developmental proteins support other functions. Moreover, other experiments suggest the proteins may actually be hormones or growth factors. These findings are not compatible with a model that has the proteins only regulating free steroid hormone levels. Obviously, much more experimentation will be necessary to reveal the functions of ABP and SHBG. The recent discoveries have offered several clues to their functions and open new routes for study. These experiments, coupled with newly developed techniques, such as gene knockout by homologous recombination, make one optimistic that the functions of these unique proteins will be deciphered in the near future.

Hormonal and clinic evaluation of patients with moderate body hair growth

Plasma prolactin (PRL), gonadotropins (FSH, LH), estradiol-17 beta (E2), progesterone (P), total testosterone (T), sex steroid binding protein (SBP), T/SBP index, cortisol (F), 17-OH-progesterone (17OH-P), dehydroepiandrosterone sulphate (DHEA-S) and androstenedione (A), were measured in 50 fertile non-obese women presenting with moderate body hair growth and in 30 matched controls. DHEA-S and PRL were significantly higher (P < 0.002, P < 0.001, respectively) and SBP was lower (P < 0.001) in patients than in controls. Regression analyses showed that PRL levels were independent of the other parameters, while a negative correlation was found between DHEA-S and SBP values. Since the decision to treat a woman with mild body hair growth is usually a clinical one, PRL behaviour has to be taken into account before deciding the type of treatment. Clinical improvement was observed in subjects treated with ethynylestradiol plus desogestrel or plus cyproterone acetate, so as to produce an increase in SBP rather than a decrease in DHEA-S.

Serum sex hormone-binding globulin, cardiovascular risk factors, and adrenal cortisol responses to dexamethasone and corticotropin

Basal cortisol levels and cortisol responses to dexamethasone (DXM) and corticotropin were studied in relation to serum levels of sex hormone-binding globulin (SHBG), testosterone (T), free T, estradiol (E2), insulin-like growth factor I (IGF-I), high-density lipoprotein cholesterol (HDLC), triglycerides (TG), and insulin in 30 men. SHBG was positively correlated to age (P < .01), HDLC (P < .05), and total T (P < .05) and negatively correlated to TG (P < .02) and insulin (P < .001). SHBG was inversely related to corticosteroid-binding globulin (P < .05), but was not significantly associated with IGF-I. Free T was positively related to TG (P < .05), insulin (P < .01), total T (P < .001), and basal (P < .01) and free cortisol (P < .05). Corticotropin-stimulated cortisol responses were negatively associated with SHBG (P < .001) and positively associated with insulin (P < .01). Multiple linear regression analyses with SHBG as the dependent variable indicated that cortisol response alone explained 34.0% and together with age 46.2% of the variation of SHBG levels. Only insulin and age, but not cortisol response, remained significant predictors of SHBG concentrations when entered simultaneously into the mathematical model; this model explained 55.1% of the variation of SHBG levels. Thus, in addition to insulin and age, cortisol reserves and secretion seem to have significant associations with serum SHBG and free T concentrations.

Plasma levels of C19 steroid glucuronides in pre-menopausal women with non-classical congenital adrenal hyperplasia

Recent reports have thrown doubt on the role of measurements of plasma 5 alpha-androstane-3 alpha,17 beta-diol glucuronide (3 alpha-diolG) as a marker of peripheral androgen metabolism in women with polycystic ovarian syndrome and idiopathic hirsutism. It has been suggested that a plasma profile of C19 steroid glucuronides may be more informative. While preliminary data indicates that both 3 alpha-diolG and androsterone G (ADTG) may arise from adrenal steroid precursors, there have been no reports of C19 steroid glucuronides in women with non-classical, or late-onset congenital adrenal hyperplasia (NC-CAH), who constitute a significant proportion of the hirsute female population. We therefore measured plasma levels of 3 alpha-diolG, ADTG and dihydrotestosterone G (DHTG) before and following a standard Cortrosyn test in 15 symptomatic and 3 asymptomatic NC-CAH patients, 5 heterozygote carriers for 21-hydroxylase deficiency (NCHETS) and 18 normal women. The effects of chronic glucocorticoid (GCR) therapy (greater than 3 months) on the C19 steroid glucuronide profile in the symptomatic patients was also investigated. Baseline plasma levels of all 3 glucuronides were significantly (P less than 0.001) higher in symptomatic patients compared with either normals or NCHETS. However, the order of discrimination was ADTG greater than 3 alpha-diolG greater than DHTG. There were no significant differences between steroid glucuronide levels for NCHET and normal women and the C19 steroid glucuronide concentrations for the asymptomatic NC-CAH patients were greater than 2 SD above the normal means. Moderate clinical improvement was observed in all patients receiving oral GCR therapy and was accompanied by approx. 80% suppression of the plasma levels of all 3 C19 steroid glucuronides. This contrasts with a mean suppression of androstenedione of only 50%. However, plasma levels of the C19 steroid glucuronides were not significantly increased in response to a short ACTH stimulation test. This may be explained by the fact that the androgen glucuronides are thought to be peripherally formed metabolites derived from unconjugated glandular secreted androgen precursors and thus their synthesis at 60 min following adrenal stimulation may lag substantially behind that of their respective precursors. There were significant linear correlations between the levels of all 3 glucuronides, but neither correlated with Ferriman-Gallway scores, body mass index or 17-hydroxyprogesterone levels.(ABSTRACT TRUNCATED AT 400 WORDS)

The ovary-suppression test in the evaluation of hyperandrogenemia

Forty hyperandrogenemic women were investigated in order to determine whether the source of androgen excess could be attached to a dysfunction of the ovary or the adrenal cortex with a higher degree of accuracy when both steroid-producing organs were subjected to a supposedly specific suppression test. Dexamethasone (DXM) was administered at a dose of 2 mg for 2 days. The ovary-suppression test (OST) was carried out after a combined preparation containing 35 micrograms of ethinyl estradiol and 2 mg of cyproterone acetate (EE-CPA) had been taken for 2-3 weeks. Before and after the tests, the serum levels of testosterone (T), free testosterone (fT), DHEA-S and SHBG were determined. Serum T was lowered by DXM and EE-CPA to the same degree: the latter was more effective with respect to fT. DHEA-S responded much better to DXM than to EE-CPA. The basal level of SHBG was below the lower limit of the norm in 45% of the women. This indicates that hyperandrogenemia can be associated with normal and subnormal levels of SHBG. T and/or fT were elevated in all 40 women. DHEA-S was higher than normal in only 22 of the 40. DXM normalized the DHEA-S level in all but 1 case. In another 18 women, serum T and fT remained unaffected by DXM. This indicates an ovarian source of androgen excess in these cases. The number of cases was reduced from 18 to 4 when the OST was carried out. Even though DXM and EE-CPA are not completely organ-specific in action, the combination of both suppression tests seems to allow a higher degree of discrimination to be made between an ovarian and an adrenal component of hyperandrogenemia than is possible with either test alone.

Dexamethasone and spironolactone in the treatment of non-tumorous hyperandrogenism

To test the hypothesis that a combination therapy with dexamethasone and spironolactone in hirsute women with menstrual disorders due to non-tumorous hyperandrogenism might yield better results than monotherapy with spironolactone, we evaluated 25 women randomly assigned to dexamethasone-spironolactone (n = 15) and spironolactone (n = 10) groups. The Ferriman-Gallwey score and hormonal levels (LH, FSH, PRL, serum testosterone, androstenedione, dehydroepiandrosterone sulfate, estradiol, estrone and salivary testosterone) were determined before and after 6 months of therapy. There were comparable results, with a significant drop in the Ferriman-Gallwey score, in serum androstenedione and estrone concentrations and in salivary testosterone levels in both groups. The only difference between the two groups after therapy was a significant fall in serum dehydroepiandrosterone levels in patients treated with the combination therapy. The results indicate that the combination therapy with spironolactone and dexamethasone presents no real advantage over therapy with spironolactone alone, for the initial treatment of non-tumorous hyperandrogenism.