Clinical phenotypes, insulin secretion, and insulin sensitivity in kindreds with maternally inherited diabetes and deafness due to mitochondrial tRNALeu(UUR) gene mutation.

An A-to-G transition in the mitochondrial tRNALeu(UUR) gene at base pair 3243 has been shown to be associated with the maternally transmitted clinical phenotype of NIDDM and sensorineural hearing loss in white and Japanese pedigrees. We have detected this mutation in 25 of 50 tested members of five white French pedigrees. Affected (mutation-positive) family members presented variable clinical features, ranging from normal glucose tolerance (NGT) to insulin-requiring diabetes. The present report describes the clinical phenotypes of affected members and detailed evaluations of insulin secretion and insulin sensitivity in seven mutation-positive individuals who have a range of glucose tolerance from normal (n = 3) to impaired (n = 1) to NIDDM (n = 3). Insulin secretion was evaluated during two experimental protocols: the first involved the measurement of insulin secretory responses during intravenous glucose tolerance test, hyperglycemic clamp, and intravenous injection of arginine. The second consisted of the administration of graded and oscillatory infusions of glucose and studies to define C-peptide kinetics. This protocol was aimed at assessing two sensitive measures of beta-cell dysfunction: the priming effect of glucose on the glucose-insulin secretion rate (ISR) dose-response curve and the ability of oscillatory glucose infusion to entrain insulin secretory oscillations. Insulin sensitivity was assessed by euglycemic-hyperinsulinemic clamp. Evaluation of insulin secretion demonstrated a large degree of between- and within-subject variability. However, all subjects, including those with NGT, demonstrated abnormal insulin secretion on at least one of the tests. In the four subjects with normal or impaired glucose tolerance, glucose failed to prime the ISR response, entrainment of ultradian insulin secretory oscillations was abnormal, or both defects were present. The response to arginine was always preserved, including in subjects with NIDDM. Insulin resistance was observed only in the subjects with overt diabetes. In conclusion, the pathophysiological mechanisms responsible for the development of NIDDM and insulin-requiring diabetes in this syndrome are complex and might include defects in insulin production, glucose toxicity, and insulin resistance. However, our data suggest that a defect of glucose-regulated insulin secretion is an early possible primary abnormality in carriers of the mutation. This defect might result from the progressive reduction of oxidative phosphorylation and implicate the glucose-sensing mechanism of beta-cells.

Androgen excess in women with acne alone compared with women with acne and/or hirsutism.

Acne is known to be one of the features of hyperandrogenism. The aim of the present work was to study women with persistent acne and without other evidence of hyperandrogenism, such as hirsutism, alopecia, or irregular menses. Among 87 female patients with acne and/or hirsutism, we defined three groups: group 1 (n = 29), patients having treatment-resistant acne without menstrual disturbance, alopecia, or hirsutism; group 2 (n = 27), patients with acne and hirsutism; and group 3 (n = 31), patients with hirsutism alone. Clinical chemistry criteria for hyperandrogenism were based on elevated values of one or more of the following parameters: plasma testosterone, delta-4-androstenedione, dehydroepiandrosterone, urinary 5 alpha-androstane 3 alpha-17 beta-diol, and 17-ketosteroids (with chromatography). Plasma and urine samples were drawn between the 18th and 25th days of the cycle. Among group 1 patients, we found 25 subjects (86%) with hyperandrogenism, according to these laboratory criteria. The etiologies were: polycystic ovary syndrome (36%), adrenal hypersecretion (40%, of which 12% showed secondary polycystic ovaries), isolated increase in 5 alpha-androstane 3 alpha-17 beta-diol (20%), and hyperandrogenism without diagnosis (4%). The parameters were found to be more elevated in these patients than in a control group of 30 normal volunteer women. In groups 2 and 3, the findings were essentially the same as in group 1, except for increased levels of testosterone and the testosterone/SHBG ratio. Furthermore, it was evident that persistent acne may be an isolated sign of hyperandrogenism.

Effect of oral isotretinoin treatment on skin androgen receptor levels in male acneic patients.

An oral daily dose (mean +/- SD, 0.75 +/- 0.05 mg/kg) of isotretinoin was administered for 3 months to six male patients with acne (scores of 4 and 5 according to Rosenfield). The therapy resulted in complete resolution of acne in four patients and improved acne significantly (score 1) in two patients. In accordance with recent findings, no change in serum testosterone and significant decreases in 5 alpha-dihydrotestosterone, 5 alpha-androstane-3 alpha,17 beta-diol glucosiduronate, and androsterone glucosiduronate levels were observed after treatment. Androgen receptor status was investigated in back skin biopsies obtained in acne areas before and after 3 months of isotretinoin treatment. The treatment did not modify the binding affinity constant of skin androgen receptor (0.44 vs. 0.32 nmol/L), but it did induce a 2.6-fold decrease in its binding capacity constant (62 vs. 24 fmol/mg cytosolic protein), as assessed by Scatchard plot and confirmed immunologically by Western blot analysis. These data clearly showed that skin androgen receptor was sensitive to oral isotretinoin administration in acneic patients. The decrease in skin androgen receptor levels (this study) and the recently reported suppression of skin 5 alpha-dihydrotestosterone production by isotretinoin treatment appeared consistent with the involvement of androgen receptor and 5 alpha-dihydrotestosterone in the pathogenesis of acne. Indeed, sebum production is under androgen control, and an abnormal response of the pilosebaceous unit to androgens appears to be implicated in the pathogenesis of acne. These observations were consistent with the absence of sebum in complete androgen-insensitive patients and normal sebum production in male pseudohermaphrodites.

Adrenocortical 11 beta-hydroxylation defect in adult women with postmenarchial onset of symptoms.

Four cases in adults of a deficiency in the 11 beta-hydroxylation of corticosteroids were investigated by both basal and dynamic biological studies. Symptoms varied from patient to patient; hirsutism, menstrual disturbance, acne, deepening of the voice, and arterial hypertension appeared post puberty. Basal testing demonstrated elevated levels of plasma androgens. These include delta 4-androstenedione (patients, 3.80-6.43 ng/ml; normal, 1.33 +/- 0.33 ng/ml), urinary 17-ketosteroids (patients, 11.8-16.7 mg/24 h; normal, 5-10 mg/24 h), and urinary dehydroepiandrosterone. The basal tests were often insufficient to show the accumulation of the precursors (especially 17-hydroxyprogesterone) which are often given as evidence for an increase in ACTH stimulation. In studying the levels of the mineralocorticoids, there was shown to be an increased basal level of tetrahydrodeoxycorticosterone (patients, 142-317 microgram/24 h; normal, 60-80 microgram/24 h) which was raised by ACTH stimulation. These results, therefore, confirm the characteristic partial enzyme defect and give evidence for the heterogeneity of this syndrome. Based on the above observations, we believe it is appropriate to rename this condition adult adrenocortical 11 beta-hydroxylation defect rather than late-onset congenital adrenal hyperplasia.

Accumulation of 5 alpha-reduced androgen glucosiduronates associated with impaired removal in young male hemodialysis patients.

Hypothalamic-pituitary gonadal function is commonly altered in dialysis patients. Even though an improvement in general status and well-being has been noted after recombinant human erythropoietin supplementation, no significant changes were observed in the sex hormone profile. Pituitary gonadal axis as well as 5 alpha-reduced androgen glucosiduronates (i.e. 5 alpha-androstane,3 alpha,17 beta-diol and androsterone) profiles were studied in 23 young male stable dialyzed patients and compared to an age-matched group of healthy subjects. 5 alpha-Reduced androgen glucosiduronates are products of peripheral testosterone (T) metabolism and seem to be a useful tool in assessment of the male androgen status. Their polarity facilitates their urinary excretion, and their clearance is similar to the glomerular filtration rate in healthy men. We observed 1) a pituitary-Leydig cell dysfunction supported by normal serum estradiol and T levels, low free T, and increased LH levels; 2) an alteration of the dehydroepiandrosterone (DHEA) sulfate-DHEA interconversion, reflected by a dramatic decrease in DHEA while DHEA sulfate levels remained in the normal range; 3) an accumulation of 5 alpha-reduced androgen glucosiduronates, whose removal was impaired as shown by their very low sieving coefficients (< 0.012). Taken together, the above observations are consistent with alteration of spermatogenesis with respect to dialysis duration in which earlier elevated baseline serum LH levels indicate a primary defect in Leydig cell function.

Evidence for decreased androgen 5 alpha-reduction in skin and liver of men with severe acne after 13-cis-retinoic acid treatment.

To investigate the effect of 13-cis-retinoic acid (13-cis-RA) treatment on androgen metabolism in men with severe nodulocystic acne, eight men with severe acne received an oral daily dose of 0.7 mg/kg 13-cis-RA over 3 months. Exploration of androgen metabolism in serum samples, 24-h urine collections, and skin biopsies obtained before and at the end of the treatment revealed no significant alterations in serum levels of either adrenal or gonadal androgens. However, the treatment did induce significant decreases in serum levels of the 5 alpha-reduced androgens: 5 alpha-dihydrotestosterone (P < 0.02), androsterone glucosiduronate (P < 0.04), and 5 alpha-androstan-3 alpha, 17 beta-diol glucosiduronate (P < 0.004). Unlike serum, the urinary 5 alpha-reduced metabolites 5 alpha-androstan-3 alpha, 17 beta-diol and androsterone did not vary significantly despite a decrease in the excretion of the latter. Moreover, a marginally significant increase in urinary excretion of etiocholanolone, very similar to the decrease in androsterone excretion, was observed. The ratio of androsterone to etiocholanolone decreased significantly (P < 0.004) after 13-cis-RA therapy and suggested a metabolic deviation from the androgen 5 alpha- to 5 beta-reduction pathway in the liver. The most pronounced effect was observed in skin biopsies, which lost 80% of their ability to form 5 alpha-dihydrotestosterone (P < 0.001). It is concluded that 13-cis-RA therapy in men with severe nodulocystic acne did not alter gonadal or adrenal functions, but it did induce 1) a highly significant decrease in 5 alpha-dihydrotestosterone formation by skin biopsies; 2) significant decreases in serum 5 alpha-dihydrotestosterone, androsterone glucosiduronate, and 5 alpha-androstan-3 alpha, 17 beta-diol glucosiduronate; and, finally, 3) deviation of the liver androgen 5 alpha- to 5 beta-reduction pathway. The effect of 13-cis-RA treatment on severe acne is consistent with the dramatic decrease in androgen 5 alpha-reduction observed mainly in the skin.

Genetic, biochemical, and clinical studies of patients with A328V or R213C mutations in 11betaHSD2 causing apparent mineralocorticoid excess.

Apparent mineralocorticoid excess is a recessively inherited hypertensive syndrome caused by mutations in the 11beta-hydroxysteroid dehydrogenase type 2 gene, which encodes the enzyme normally responsible for converting cortisol to inactive cortisone. Failure to convert cortisol to cortisone in mineralocorticoid-sensitive tissues permits cortisol to bind to and activate mineralocorticoid receptors, causing hypervolemic hypertension. Typically, these patients have increased ratios of cortisol to cortisone and of 5alpha- to 5beta-cortisol metabolites in serum and urine. We have studied 3 patients in 2 families with severe, apparent mineralocorticoid excess and other family members in terms of their genetic, biochemical, and clinical parameters, as well as normal controls. Two brothers were homozygous for an A328V mutation and the third patient was homozygous for an R213C mutation in the 11beta-hydroxysteroid dehydrogenase type 2 gene; both mutations caused a marked reduction in the activity of the encoded enzymes in transfection assays. The steroid profiles of the 7 heterozygotes and 2 other family members studied were completely normal. The results of a novel assay used to distinguish 5alpha- and 5beta-tetrahydrometabolites suggest that 5beta-reductase activity is reduced or inhibited in apparent mineralocorticoid excess. In 1 patient undergoing renal dialysis for chronic renal insufficiency, direct control of salt and water balance completely corrected the hypertension, emphasizing the importance of mineralocorticoid action in this syndrome.

Comparison of basal and adrenocorticotropin-stimulated plasma 21-deoxycortisol and 17-hydroxyprogesterone values as biological markers of late-onset adrenal hyperplasia.

Plasma 21-deoxycortisol (21-DOF) and 17-hydroxyprogesterone (17-OHP) concentrations were assayed before (basal) and 1 h after ACTH stimulation in 4 groups of normal subjects (35 follicular phase women, 22 luteal phase women, 33 adult men, and 15 prepubertal children) and in a group of 31 patients with the late-onset form of congenital adrenal hyperplasia (LOCAH) due to 21-hydroxylase deficiency as well as in 31 LOCAH) heterozygotes. The mean basal plasma 21-DOF concentrations in each of the 4 groups of normal subjects were between 8 ng/dL (0.23 nmol/L) and 11 ng/dL (0.31 nmol/L), and they increased significantly after ACTH stimulation to between 36 ng/dL (1.04 nmol/L) and 44 ng/dL (1.27 nmol/L). There were no differences in basal or ACTH-stimulated plasma 21-DOF levels in these 4 groups, whereas their basal and post-ACTH plasma 17-OHP levels did vary. Among the LOCAH patients, 83.8% had basal plasma 21-DOF levels and 61.2% had basal plasma 17-OHP levels higher than the highest basal 21-DOF [30 ng/dL (0.86 nmol/L)] and 17-OHP [450 ng/dL (13.61 nmol/L)] concentrations in the normal subjects, and all individual 21-DOF and 17-OHP levels after ACTH stimulation [greater than or equal to 404 ng/dL (11.67 nmol/L) and greater than or equal to 1040 ng/dL (31.47 nmol/L), respectively] were markedly higher than the highest 21-DOF [76 ng/dL (2.19 nmol/L)] and 17-OHP [580 ng/dL (17.55 nmol/L)] levels in the normal subjects. The mean post-ACTH/basal plasma level ratios among the LOCAH patients were 19.75 for 21-DOF and 8.03 for 17-OHP. In LOCAH heterozygotes, basal 21-DOF values were higher than normal in 48.3%, and post-ACTH values were higher than normal in 93.5% of the cases. In contrast, basal plasma 17-OHP levels were similar in LOCAH heterozygotes and normal subjects, and only 16.1% of the LOCAH heterozygotes had post-ACTH plasma 17-OHP levels higher than the highest normal value. If sex and phase of the menstrual cycle are taken into account, along with the incremental responses (post-ACTH minus baseline value) of plasma 21-DOF and 17-OHP, to compare LOCAH heterozygotes and normal subjects, the discriminating power for detection of heterozygocity was somewhat increased for 21-DOF (to 100%) and appreciably increased for 17-OHP (to 30%).(ABSTRACT TRUNCATED AT 400 WORDS)

Prenatal diagnosis of 21-hydroxylase deficiency congenital adrenal hyperplasia by simultaneous radioimmunoassay of 21-deoxycortisol and 17-hydroxyprogesterone in amniotic fluid.

Amniotic fluid levels of 21-deoxycortisol (21-DOF) and 17-hydroxyprogesterone (17-OHP) were measured in 49 pregnancies, including 31 pregnancies at risk for CAH. The results were compared with those obtained by HLA typing and linkage analysis to a HLA DNA probe. The mean amniotic fluid levels in the control pregnancies were 0.28 nmol/L for 21-DOF and 4.1 nmol/L for 17-OHP. The levels were similar in early and midpregnancy for 21-DOF (0.29 vs. 0.27 nmol/L) and 17-OHP (3.4 vs. 4.2 nmol/L). The amniotic fluid 21-DOF level was 1.75 nmol/L in affected pregnancies, significantly higher than in the control pregnancies (mean, 0.28 nmol/L). The mean amniotic fluid 17-OHP level in the affected pregnancies (30.5 nmol/L) also was significantly higher than that in the control pregnancies (4.10 nmol/L). Simultaneous measurement of 21-DOF and 17-OHP levels in amniotic fluid from 10-18 weeks of gestation can be used for early diagnosis of congenital adrenal hyperplasia.

Circadian variations in plasma levels of hypophyseal, adrenocortical and testicular hormones in men infected with human immunodeficiency virus.

Alterations in the circadian time structure of the secretion of several hormones were investigated in 13 male patients infected with human immunodeficiency virus (HIV). Seven were asymptomatic (classified CDC II, according to the criteria of the Atlanta Centers for Disease Control), and 6 had acquired immunodeficiency syndrome (CDC IV). Ten healthy males volunteered as controls. Plasma levels of dehydroepiandrosterone (DHEA) and its sulfate (DHEA-S), cortisol, testosterone, ACTH, and beta-endorphin were determined by RIA in blood samples obtained every 4 h from 0830-0830 h the next morning. Data were analyzed both by two-way analysis of variance and the cosinor method. Circadian rhythms were statistically validated for each of the six hormones in each of the three groups of subjects. Compared with the control subjects, mesors (24-h adjusted means) were significantly higher for cortisol and lower for DHEA, DHEA-S, and ACTH (P less than 0.001 for all four hormones) in all HIV-infected patients. Plasma testosterone mesors were similar in controls and CDC II patients, but decreased significantly in the CDC IV patient group (P less than 0.05). Analysis of the circadian rhythms of plasma hormone levels clearly indicated an altered adrenal hormonal state in HIV-infected male patients, even during the asymptomatic period of the infection. For instance, plasma cortisol at 0430 h was more than twice as high in HIV-infected patients as it was in time-qualified controls. Although patients already had elevated plasma cortisol and lowered adrenal androgen levels at this stage, hypogonadism was not observed, as gauged by plasma testosterone concentrations. We speculate that the primary hormonal defect in HIV-infected patients is increased cortisol secretion resulting from circadian-varying stimulation of the adrenal cortex by a factor other than pituitary ACTH. This factor might be a stimulating substance secreted primarily by infected immune cells. Excess cortisol would lower adrenal androgen secretion by shifting adrenal steroid biosynthesis toward glucocorticoids and decreasing pituitary ACTH secretion via a negative feedback mechanism.

Increased plasma 21-deoxycorticosterone (21-DB) levels in late-onset adrenal 21-hydroxylase deficiency suggest a mild defect of the mineralocorticoid pathway.

Plasma 21-deoxycorticosterone (21-DB) concentrations were measured before (basal) and 1 h after ACTH stimulation in a population of 34 normal subjects, 18 patients with the late-onset form of congenital adrenal hyperplasia (LO-CAH) due to 21-hydroxylase deficiency, and 19 LOCAH heterozygotes. For comparison, plasma 21-deoxycortisol (21-DOF) and 17-hydroxyprogesterone (17-OHP) were determined simultaneously in the same subjects. Plasma 21-DB concentrations as well as those of 21-DOF did not vary significantly as a function of age, sex, or phase of the menstrual cycle, in contrast to plasma 17-OHP. The mean plasma 21-DB concentrations in normal subjects (adult men, follicular and luteal phase women, and children) were 19.0 +/- 9.5 (+/- SD) pmol/L before and 73.2 +/- 31.0 after ACTH stimulation. In the LOCAH patient group, the mean post-ACTH plasma 21-DB concentration was 1736.0 +/- 1243.0 pmol/L, and all values were above the highest post-ACTH value (148.2 pmol/L) in the normal subjects. Similarly, in the LOCAH patients the post-ACTH plasma 21-DOF concentration was 33.7 +/- 20.3 nmol/L, and the post-ACTH plasma 17-OHP value was 134.0 +/- 70.6 nmol/L; all LOCAH patients had supranormal responses to ACTH. However, 38.9%, 11.2% and 16.7% of the basal plasma 21-DB, 21-DOF, and 17-OHP values in the LOCAH patients overlapped those in the normal subjects. There was a rather large overlap (63.2%) in post-ACTH plasma 21-DB levels between the LOCAH heterozygotes and the normal subjects; it was less than the overlap in plasma 17-OHP (74%) and more than the overlap in plasma 21-DOF values (5.2%) in these same 2 groups. There was moderate overlap (21%) in the post-ACTH plasma 21-DB levels between the LOCAH heterozygotes and LOCAH patients, but no overlap between these 2 groups for either 21-DOF or 17-OHP. The abnormally elevated post-ACTH plasma 21-DB levels found in all the LOCAH patients as well as in some LOCAH heterozygotes suggest the existence of minor 21-hydroxylase deficiency in the mineralocorticoid synthetic pathway in these patients in addition to the well known impairment in the glucocorticoid pathway demonstrated by the elevated post-ACTH 21-DOF and 17-OHP levels.

Effects of RU 486 on adrenal steroidogenesis in the guinea-pig.

Recent reports have shown that RU 486, a synthetic glucocorticoid and progestin antagonist, has direct effects on tissues secreting steroids. In order to characterize the effects of RU 486 on steroidogenesis further, guinea-pig fasciculata-glomerulosa (FG) cells in primary culture were treated for 48 h with RU 486. RU 486 caused an alteration of basal as well as ACTH-stimulated steroid secretion. Corticosterone and cortisol secretion decreased by 50% while the secretion of 17-hydroxyprogesterone and C19 steroids were increased. The activity of steroidogenic enzymes was measured using tritiated steroids. In RU 486-treated cells, the activity of 21-hydroxylase was dramatically inhibited while there was an increase in 17-hydroxylase and 17,20-desmolase activities. The effects of RU 486 on enzyme activities were dependent upon dose and time. The effects of the compound were not reversed by concomitant treatment of FG cells with R-5020 or dexamethasone, thus suggesting that RU 486 acted directly on steroidogenic enzymes to alter their activity.

The mechanism of inhibition of endothelin-1-induced stimulation of DNA synthesis in rat articular chondrocytes.

Endothelin-1 (ET-1) is a potent mitogen for rat articular chondrocytes (AC) in short term culture (24 h). Prolonged incubation (72 h) of AC with ET-1 resulted in inhibition of [3H]thymidine incorporation. This inhibition seemed to be mediated by prostaglandins (PGs) released in response to ET-1, since indomethacin (INDO) enhanced ET-1-induced [3H]thymidine incorporation. In agreement with this hypothesis, exogenous prostaglandins (PGE2, PGF2alpha and TxB2) blocked all basal, ET-1-induced and ET-1 induced-INDO-enhanced [3H]thymidine incorporation and ET-1 stimulated PGE2 release in a time and concentration-dependent manner. INDO also blocked cGMP production and 6-anilino-5,8-quinolinedione, a relatively specific inhibitor of cGMP formation, enhanced the stimulation and suppressed the inhibition of ET-1-induced DNA synthesis. In addition, 8-bromo-cGMP, an analogue of cGMP, blocked at all time periods studied, both basal and ET-1-induced incorporations of [3H]thymidine. Thus, PGs produced in response to ET-1 counteract the ET-1-induced stimulation of [3H]thymidine incorporation into rat AC by increasing cGMP production.

Assessment of the follicular cortisol:cortisone ratio

Cortisol and cortisone concentrations in serum and follicular fluid (FF) from women undergoing in-vitro fertilization (IVF) treatment were monitored. Four groups were included: group 1, women in their natural menstrual cycle having an endogenous mid-cycle surge of gonadotrophins; group 2, women in their natural menstrual cycle receiving human chorionic gonadotrophin (HCG) for ovulation induction; group 3, women receiving exogenous gonadotrophins for ovarian stimulation and HCG for ovulation induction; and group 4, women receiving exogenous gonadotrophins for ovarian stimulation, follicles being aspirated immediately before administration of HCG. In this study, 12 follicles contained oocytes which resulted in clinical pregnancy after IVF. Cortisone concentrations were significantly higher in FF compared with that of matched serum samples, while the opposite was observed for cortisol, resulting in cortisol:cortisone ratios being significantly lower in FF compared with serum. FF from group 4 showed significantly higher cortisone concentrations than FF from each of the other three groups. FF from group 1 showed significantly higher cortisone concentrations and significantly lower cortisol:cortisone ratios in comparison with groups 2 and 3. None of the observed parameters pinpointed any of the follicles containing oocytes which resulted in a clinical pregnancy. The intrafollicular concentrations of cortisol and cortisone suggest that pre-ovulatory follicles actively convert cortisol to cortisone. Neither FF concentrations of cortisol and cortisone nor the cortisol:cortisone ratio seem to reflect implantation potential of the derived pre-embryos.

11 beta-Hydroxysteroid dehydrogenase deficit: a rare cause of arterial Hypertension. Diagnosis and therapeutic approach in two young brothers.

We report the clinical history and results of endocrine investigations in two brothers born to consanguineous parents, who presented with hypokalemia and arterial hypertension when they were aged 2 and 6 years. The hormonal serum assay results, including extremely low values for aldosterone and plasma renin activity, favored the existence of apparent mineralocorticoid excess. A diagnosis of 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) deficiency was made, based on assays of the hydrogenated urinary metabolites of cortisol and cortisone, as well as of corticosterone and dehydrocorticosterone. Indeed we found a very low rate of urinary elimination of cortisone metabolites: tetrahydrogenated cortisone was reduced to between 0.10 and 30 mumol/24 h, which is 15-100 times lower than the normal rate; hexahydrogenated cortolones alpha and beta were found to be 7- to 20-fold lower than normal levels; and the 11-keto-17-ketosteroid derivatives of cortisone were also reduced. Urinary elimination of the cortisol-reduced metabolites 5 beta- and 5 alpha-tetrahydrogenated cortisol were slightly reduced or normal. These results argue in favor of a deficit in the enzyme 11 beta-HSD, which oxidizes cortisol into cortisone. A moderate defect in the conversion of cortisol into 5 beta-THF compared to normal conversion into 5 alpha-THF was also found. With respect to corticosterone metabolism, we demonstrated the presence of a defect in the oxidation of that steroid into dehydrocorticosterone, also due to the deficit in 11 beta-HSD. Arterial hypertension and hypokalemia were corrected by treatment with dexamethasone, concomitantly with correction of the low aldosterone and plasma renin activity levels. On the other hand, during this treatment, urinary concentrations of the metabolites of cortisol, cortisone and corticosterone were only moderately affected.

Insulin secretion and insulin sensitivity in diabetic and non-diabetic subjects with hepatic nuclear factor-1alpha (maturity-onset diabetes of the young-3) mutations.

OBJECTIVE: To evaluate insulin secretion and sensitivity in affected (diabetes mellitus or impaired glucose tolerance; n=7) and in unaffected (normal glucose tolerance; n=3) carriers of hepatocyte nuclear factor-1alpha (maturity-onset diabetes of the young-3 (MODY3)) gene mutations. METHODS: Insulin secretion was assessed by an i.v. glucose tolerance test (IVGTT), hyperglycemic clamp and arginine test, and insulin sensitivity by an euglycemic hyperinsulinemic clamp. Results were compared with those of diabetic MODY2 (glucokinase-deficient) and control subjects. RESULTS: The amount of insulin secreted during an IVGTT was decreased in affected MODY3 subjects (46+/-24 (s.d.) pmol/kg body weight (BW)) as compared with values in MODY2 (120+/-49pmol/kg BW) and control (173+/-37pmol/kg BW; P=0.0004) subjects. The amount of insulin secreted during a 10mmol/l glucose clamp was decreased in affected MODY3 subjects (171+/-78pmol/kg BW) and MODY2 subjects (302+/-104pmol/kg BW) as compared with control subjects (770+/-199pmol/kg BW; P=0.0001). Insulin secretion in response to arginine was decreased in affected MODY3 subjects. Milder and heterogeneous defects were observed in the unaffected MODY3 subjects; the amount of insulin secreted during the hyperglycemic clamp was 40-79% of that of controls. The response to arginine was abnormally delayed. Insulin sensitivity was decreased in diabetic but not in non-diabetic MODY3 subjects. CONCLUSIONS: Beta-cell dysfunction in response to glucose and arginine is observed in affected and unaffected MODY3 subjects. The MODY3 and MODY2 subtypes present different insulin secretion profiles. Secondary insulin resistance might contribute to the chronic hyperglycemia of MODY3 patients and modulate their glucose tolerance.

Effect of ACTH on steroidogenic enzymes in guinea pig fasciculata-glomerulosa cells: changes in activity and mRNA levels.

Adrenocorticotropin (ACTH) is known to exert an acute effect on adrenal steroidogenesis as well as long-term effects by regulation of gene expression. In order to further study the long-term action of ACTH, guinea pig fasciculata-glomerulosa (FG) cells in primary culture were treated for up to 72 h with ACTH. The effects of this treatment on steroid secretion, enzyme activity and mRNA levels for steroid enzymes were measured. While the rate of 17-deoxy C-21 steroid secretion decreased over the 72-h period of incubation with ACTH, the 17-hydroxy C-21 steroid secretion rate remained constant for the first 24 h of incubation and declined thereafter; the rate of 4-ene C-19 steroid secretion increased over the 72-h incubation period. ACTH treatment increased 17-hydroxylase and 17,20-lyase activities and the maximal stimulation was reached after 48 h. In contrast, the activity of 21-hydroxylase (P450c21) steadily declined over the 72-h incubation period. ACTH also caused an increase in mRNA levels for P450c21, 17-hydroxylase and 17,20-lyase (P450c17), 3 beta-hydroxysteroid dehydrogenase 4-ene-5-ene-isomerase (3 beta-HSD) and cholesterol side-chain cleavage enzyme (P450scc). The maximal stimulation for the four mRNAs was observed after 18 h of incubation with ACTH, decreasing afterwards except for P450c17 mRNA levels which remained elevated over the 72-h incubation period. Despite the increase in mRNA levels for 3 beta-HSD and P450c21, no increase in their respective enzyme activities was observed and 21-hydroxylase activity even declined over the 72-h incubation period with ACTH, thus suggesting that mechanism(s) other than gene expression alone regulate steroid secretion in FG cells. In conclusion ACTH caused major changes in steroid distribution due to increased 17-hydroxylase and 17,20-lyase activities and decreased 21-hydroxylase activity in FG cells in culture. Moreover, our data revealed major differences in the induction of mRNAs for steroidogenic enzymes and their activities following ACTH treatment.

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.

Enzyme-catalyzed synthesis of radiolabeled 5-pregnen-3 beta-ol-20-one sulfate.

The enzymatic synthesis of [3H]5-pregnen-3 beta-ol-20-one sulfate using [3H]5-pregnen-3 beta-ol-20-one, 3'-phosphoadenosine-5'-phosphosulfate and hydroxysteroid sulfotransferase 1 purified from rat liver is reported. The described procedure allowed the obtainment of high specific activity [3H]5-pregnen-3 beta-ol-20-one sulfate in yields ranging from 78 to 86% with respect to [3H]5-pregnen-3 beta-ol-20-one. Two-dimensional thin-layer chromatography was used to purify [3H]5-pregnen-3 beta-ol-20-one sulfate which upon solvolysis resulted in the formation of [3H]5-pregnen-3 beta-ol-20-one. The identity both of the synthesized compound and the solvolysed one was confirmed by reversed-phase high pressure liquid chromatography, and 2-dimensional thin-layer chromatography.

Highly sensitive and specific time-resolved fluoroimmunoassay (TR-FIA) of cyproterone acetate and free cyproterone.

We have developed a non-isotopic TR-FIA for Cyproterone acetate and Cyproterone in plasma. Synthesis of the biotinylated tracers, biotinylated Cyproterone acetate, and Cyproterone, as well as the preparation of anti-Cyproterone acetate and anti-Cyproterone antisera are reported. The specificity of anti-Cyproterone acetate antiserum resulting from the coupling of link bridge (link bridge between steroid and BSA), on the 3-position on the steroid skeleton, allowed to carry out the Cyproterone acetate assay directly on extracted plasma (without chromatography). On the other hand Cyproterone assays require a purification step, including extraction plus chromatography, because the plasma Cyproterone acetate concentrations in Cyproterone acetate-treated women are 200 times higher than for Cyproterone. Theses plasma TR-FIA of Cyproterone acetate and Cyproterone presented the advantage of needing only small doses of radioactivity for recovery controls, and better practicability related to the only existing RIA described to date.