Biomedical subjects

B Allolio

Publications and source records attributed to B Allolio.

At least 37 records · Page 2Linked to original sources

PubMed2001

[Severe Vitamin D(dihydrotachysterol)-intoxication with temporary anemia and hypercalcemia responsive to bisphosphonates]

Severe Vitamin D(dihydrotachysterol)-intoxication with temporary anemia and hypercalcemia responsive to bisphosphonates. HISTORY AND FINDINGS: A 31-year old female patient presented with pain of her skeletal system. 6 months prior to her presentation, she underwent thyroid surgery for Graves disease. She also suffered from endocrine orbitopathy. Afterwards, she expirienced surgical hypoparathyroidism and received dihydrotachy-sterol (A.T.10 (R)) in a dose of up to 4 mg per day. The physical examination was unremarkable except for the presence of Graves' ophthalmopathy and a swelling at the left ancle. INVESTIGATIONS: Upon admittance, she had severe hypercalcemia (serum calcium: 4.1 mmol/l) with plasma intact PTH levels below the limit of detection, renal failure (serum creatinine: 5.5 mg/dl) and normocytic anemia (initial hemoglobin: 8.3 g/dl, upon rehydration: 6.6 g/dl). TREATMENT AND COURSE: Upon rehydration and induced diuresis, the renal function improved and the serum calcium came down rapidly in the early treatment phase. However, serum calcium remained elevated at around 3.0 mmol/l after 4 weeks. Only after the use of the bisphosphonate pamidronate (15 mg), serum calcium returned into the normal range and remained there. Treatment for hypoparathyroidism had to be reinstituted only 20 weeks after dihydrotachysterol had been discontinued. The anemia had resolved without any treatment at that time. CONCLUSIONS: Treatment with dihydrotachysterol and other long-acting Vitamin D preparations has to be monitored closely because of the risk of severe hypercalcemia, which may be difficult to treat. In our case, dihydrotachysterol was still active until week 20 after the drug was discontinued. Anemia should be considered as a side effect of dihydrotachysterol intoxication and does not warrant elaborate differential diagnosis in this context. A single administration of a bisphosphonate turned out to be of major therapeutic benefit and resulted in a lasting correction of hypercalcemia. Therefore, bisphosphonates should become part of the treatment regimen for vitamin D intoxication.

Journal Article↗

PubMed2001

Dehydroepiandrosterone supplementation in healthy men with an age-related decline of dehydroepiandrosterone secretion.

Serum dehydroepiandrosterone declines with age. Whether this represents a harmful deficiency or an age-related adaptation is not known. Dehydroepiandrosterone replacement in adrenal insufficiency, a state of pathological loss of dehydroepiandrosterone production, improves well-being, mood, and sexuality. To determine the effects of dehydroepiandrosterone in healthy men with a physiological, age-related decline in serum dehydroepiandrosterone sulfate, we conducted a double blind cross-over study in 22 healthy male volunteers (age range, 50-69 yr) with endogenous dehydroepiandrosterone sulfate levels below 4.1 micromol/liter (1500 ng/ml) receiving 4 months of dehydroepiandrosterone (50 mg/d) and 4 months of placebo treatment in random order, with a 1-month washout period. Dehydroepiandrosterone treatment increased serum dehydroepiandrosterone and dehydroepiandrosterone sulfate to concentrations usually found in young men. Circulating androgen levels did not change; however, androgen metabolites increased, indicating enhanced peripheral androgen synthesis. At baseline, psychometric assessment revealed normal well-being and sexuality scores. After 4 months of dehydroepiandrosterone, no effect on sexuality was observed, whereas some mood scores improved slightly, but were not significantly different from scores after placebo. Compared with placebo, dehydroepiandrosterone had no effect on serum lipids, bone markers, body composition, or exercise capacity. Thus, in contrast to previous findings in adrenal insufficiency, we found no obvious benefit of 4 months of dehydroepiandrosterone supplementation in healthy men with a physiological decline of dehydroepiandrosterone production.

Affect↗

PubMed2001

Dehydroepiandrosterone replacement in women with adrenal insufficiency: effects on body composition, serum leptin, bone turnover, and exercise capacity.

Studies in animals and humans using supraphysiological doses of dehydroepiandrosterone (DHEA) reported significant changes in body composition and carbohydrate metabolism. To investigate the metabolic action of a physiological DHEA replacement dose, we studied 24 women with adrenal insufficiency (AI; mean +/- SD age, 42.3 +/- 9.3 yr; duration of disease, 9.2 +/- 8.4 yr; body mass index, 23.4 +/- 4.0 kg/m(2)) in a double blind, placebo-controlled, randomized, cross-over design. They received 50 mg DHEA/day and placebo orally for 4 months each, with a 1 -month washout period. Measurements included fasting serum glucose, insulin, leptin, bone markers, anthropometric parameters determined by bioimpedance analysis, and exercise capacity as assessed by an incremental cycling test. DHEA did not induce any change in body mass index (placebo vs. DHEA, 23.3 +/- 4.1 vs. 23.2 +/- 3.9 kg/m(2); P = 0.39), parameters of body composition, or exercise capacity. However, compared with placebo, DHEA replacement led to a significant decrease in serum leptin (absolute change after 4 months, DHEA vs. placebo, -5.3 +/- 8.0 vs. 1.1 +/- 5.7 ng/mL; P = 0.01). This is most likely the result of the DHEA-induced normalization of circulating androgens. DHEA had no effect on fasting glucose, insulin, or the glucose/insulin ratio. Compared with placebo, serum osteocalcin increased slightly, but significantly, during DHEA treatment (absolute change after 4 months DHEA vs. placebo, +1.6 +/- 5.3 vs. -1.2 +/- 6.2 ng/mL; P = 0.02). However, urinary cross-links excretion did not change. In conclusion, replacement of DHEA in a physiological dose in patients with pathological DHEA deficiency does not have a significant effect on carbohydrate metabolism, body composition, or exercise capacity. The biological relevance of the changes in leptin and osteocalcin levels remains to be determined.

Adrenal Insufficiency↗

PubMed2001

ACTH-receptor expression, regulation and role in adrenocortial tumor formation.

The regulation of the ACTH-receptor gene is unique in that it is up-regulated by its own ligand, ACTH. Ligand-induced up-regulation of ACTH-receptor expression may be an important adaptive process directed towards optimizing adrenal responsiveness to ACTH in the context of physiological stress and the maintenance of metabolic homeostasis in which the adrenals play a pivotal role. Whereas enhancement by ligand-induced up-regulation permits a more efficient and rapid glucocorticoid response, negative feedback regulation of glucocorticoids in the hypothalamus and pituitary inhibits ACTH secretion and allows a balanced adrenal response to stress. Since the cloning of the promoter region of the ACTH receptor, considerable progress in the understanding of the regulatory processes has been made. The effects of ACTH on ACTH-receptor expression is dependent on cAMP, probably mediated through AP-1. The profound effect of three SF-1-binding sites in the ACTH-receptor promoter was demonstrated by deletion experiments. Conversely, ACTH-receptor expression can be suppressed by adrenal-specific transcription factors,like DAX-1. Despite an extensive search, no activating ACTH-receptor mutations have been found in adrenal tumors,excluding the ACTH receptor as a relevant oncogene in adrenal tumorigenesis. However, the ACTH receptor may act as a differentiation factor as suggested by LOH in adrenal carcinomas with an undifferentiated tumor type. In benign adrenal tumors, a strong correlation between ACTH-receptor expression and expression of P450 steroidogenic enzymes is evident. This close regulative relationship is lost in adrenal carcinoma, probably as a result of tumor dedifferentiation. Down-regulation of ACTH-receptor expression in normal and neoplastic tissue can be achieved by adrenostatic compounds such as aminoglutethimide and metyrapone.

Adrenal Cortex Neoplasms↗

PubMed2001

Discerning malignancy in adrenocortical tumors: are molecular markers useful?

OBJECTIVE: Adrenocortical carcinoma (ACC) is a rare neoplasm with poor prognosis. Discerning ACCs from benign adenomas histologically may be difficult if invasion into surrounding tissues or metastases are missing. DESIGN: In order to establish molecular markers for malignancy, we analyzed seven normal adrenals, three massive macronodular ACTH-independent adrenocortical hyperplasias (MMAHs), 30 adrenocortical adenomas (ACAs) and ten ACCs. METHODS: All tissues were studied for the presence of alterations in the p53 tumor suppressor gene using the PAb 1801 antibody, which detects mutant p53 protein and the pYNZ22 microsatellite marker to show loss of heterozygosity (LOH) at 17p, for expression of the proliferation-associated antigen Ki67 using the MIB1 antibody, for the rate of apoptotic tumor cells with the TdT-mediated dUTP biotin nick end labeling (TUNEL) method, and for LOH of 11q13 (menin gene locus) with the D11S956 microsatellite marker. RESULTS: 0/3 MMAH, 1/28 ACA and 3/10 ACC revealed immunopositive staining for p53. LOH for pYNZ22 was observed in 1/3 MMAH, 1/23 informative ACA and 6/6 informative ACC. The rate of apoptotic cells was significantly higher in ACC (P<0.0001 by ANOVA) than in ACA but there was some overlap between groups. The Ki67 index (% immunopositive cells) was 1.9+/-1.30% (mean+/-s.d.) in normal adrenals, 3.47+/-1.37% in MMAH, and 2.11+/-1.01% in ACA. ACC had the highest Ki67 index of 11.94+/-7.58% distinguishing all ACC from the ACA and MMAH studied with a cut-off level of 5%. LOH for 11q13 was detected in 2/3 MMAH, 5/26 ACA and 6/8 ACC. CONCLUSIONS: We conclude that a Ki67 index above 5% is a sensitive and specific indicator of ACC and may be useful in the differentiation of adenomas from carcinomas.

Adenoma↗

PubMed2000

[Osteoporosis in the male].

BACKGROUND: Osteoporotic fractures occur frequently also in men. Epidemiologic data from Germany indicate that more than 900,000 men are affected by osteoporotic fractures. Diagnosis and therapy of male osteoporosis are hampered by a lack of clinical studies. DIAGNOSIS: Risk factor analysis, conventional spine X-rays, bone densitometry and a limited number of serum and urine analyses contribute to the diagnosis of osteoporosis and the assessment of future fracture risk. Bone densitometry at the femoral neck is superior to measurements at the lumbar spine because of the high prevalence of degenerative changes at the lumbar spine in elderly men. Major risk factors for osteoporosis are hypogonadism, glucocorticoid therapy, hypercalciuria, gastrointestinal disease, and high alcohol consumption. In individual cases, bone histology or additional biochemical studies are needed to establish the cause of osteoporosis. THERAPY: Calcium and vitamin D deficits should be substituted both in prevention and treatment of male osteoporosis. Testosterone replacement therapy is effective in hypogonadism. In primary osteoporosis and in corticosteroid-induced osteoporosis, bisphosphonates (cyclical etidronate, alendronate) and fluorides are therapeutic options. CONCLUSION: Important principles in the care of men with osteoporosis are the transfer of knowledge established for postmenopausal osteoporosis and the rigorous search for secondary osteoporosis aiming at treatment of the underlying cause. Large prospective randomized trials aiming at the reduction of fracture rate in male osteoporosis are missing. They are urgently needed.

Aged↗

PubMed2000

Influence of oral dehydroepiandrosterone (DHEA) on urinary steroid metabolites in males and females.

Oral dehydroepiandrosterone (DHEA) replacement therapy may have a multitude of potential beneficial effects and exerts its action mainly via peripheral bioconversion to androgens (and estrogens). A daily dose of 50-mg DHEA has been shown by us and others to restore low endogenous serum DHEA concentrations to normal youthful levels followed by an increase in circulating androgens and estrogens. As the hepatic first-pass effect may lead to a non physiological metabolism of DHEA after oral ingestion we studied the influence of two single DHEA doses (50 and 100 mg) on the excretion of steroid metabolites in 14 elderly males [age 58.8+/-5.1 years (mean +/- SEM)] with endogenous DHEAS levels <1500 ng/ml and in 9 healthy females (age 23.3+/-4.1 years) with transient suppression of endogenous DHEA secretion induced by dexamethasone (dex) pretreatment (4x0.5 mg/day/4 days). Urinary steroid profiles in the elderly males were compared to the steroid patterns found in 15 healthy young men (age 28.9+/-5.1 years). In the females the results were compared to their individual baseline excretion without dex pretreatment. Urinary steroid determinations were carried out by semiautomatic capillary gas-liquid chromatography. In both genders DHEA administration induced significant increases in urinary DHEA (females: baseline vs. 50 mg vs. 100 mg: 361+/-131 vs. 510+/-264 vs. 1541+/-587 microg/day; males: placebo vs. 50 mg vs. 100 mg: 434+/-154 vs. 1174+/-309 vs. 4751+/-1059 microg/day) as well as in the major DHEA metabolites androsterone (A) and etiocholanolone (Et). Fifty mg DHEA led to an excretion of DHEA and its metabolites only slightly above baseline levels found in young females and in young men, respectively, whereas 100 mg induced clearly supraphysiological values. After 50 mg DHEA the ratios of urinary DHEA metabolites (A/DHEA, Et/DHEA) were not significantly different between elderly males vs. young male volunteers and young healthy females versus their individual baseline levels. In conclusion, an oral dose of 30 to 50 mg DHEA restores a physiological urinary steroid profile in subjects with DHEA deficiency without evidence for a relevant hepatic first-pass effect on urinary metabolites.

Administration, Oral↗

PubMed2000

Oral glucose tolerance testing but not intravenous glucose administration uncovers hyper-responsiveness of hypothalamo-pituitary-adrenal axis in patients with adrenal incidentalomas.

OBJECTIVE: Modern imaging techniques are detecting adrenal incidentalomas with increasing frequency. Recent data suggests food-dependent hypercortisolism in a subgroup of patients with bilateral macronodular hyperplasia due to aberrant adrenal responsiveness to gastric inhibitory polypeptide (GIP). We studied the putative influence of food intake on the hypothalamo-pituitary-adrenal (HPA) axis in patients with adrenal incidentalomas and possible mediation by GIP. PATIENTS AND MEASUREMENTS: We examined 15 mildly obese patients with adrenal incidentalomas, eight healthy, lean subjects, and seven obese patients with the metabolic syndrome, who were matched for body weight and age. Each individual underwent oral glucose tolerance testing (OGTT, 75 g glucose), i.v. glucose administration (IVGTT, 30 g glucose over 1 h) and i.v. glucose plus GIP infusion (body weight adapted leading to physiological postprandial GIP serum levels) on three occasions. Plasma glucose, ACTH and cortisol were measured from blood samples taken every 15 minutes from time - 30 minutes to + 75 minutes. RESULTS: OGTT, i.v. glucose administration and GIP infusion led to comparable glucose values within the groups. In contrast to normal subjects and patients with the metabolic syndrome, patients with adrenal incidentalomas had significantly higher mean cortisol values after oral glucose intake as compared to i.v. glucose administration or GIP infusion. The increase in cortisol levels was preceded by a corresponding ACTH increase. No significant effect of GIP administration on cortisol or on ACTH secretion could be detected. CONCLUSIONS: Patients with adrenal incidentalomas showed an abnormal responsiveness of the pituitary-adrenal axis to oral glucose administration. The cortisol peaks in these patients seemed to be ACTH-mediated and were not induced by GIP.

Adenoma↗

PubMed2000

New mechanisms of adrenostatic compounds in a human adrenocortical cancer cell line.

BACKGROUND: Adrenostatic compounds are frequently used in the treatment of patients with Cushing's syndrome and act via direct inhibition of steroidogenic enzymes. However, additional mechanisms may be involved in the blockade of adrenal steroid secretion. We therefore investigated the effects of aminoglutethimide (AG), metyrapone (MTP) and etomidate (ETO) in the human NCI-h295 adrenocortical carcinoma cell line. MATERIALS AND METHODS: Cells were incubated with increasing doses of the adrenostatic compounds. Steroid hormone secretion (cortisol, 17-OH-progesterone, DHEA-S) and cAMP synthesis were determined and Northern blot analysis and cell proliferation experiments were performed. RESULTS: ETO was the most potent adrenostatic compound inhibiting P450c11 hydroxylase at low concentrations (IC50 15 nM), and also blocking P450 side-chain cleavage (scc) enzyme (IC50 400 nM) at higher concentrations. The pattern of enzyme inhibition was similar for MTP with an IC50 of 3-5 microM for P450c11 and 17 microM for P450scc, while AG blocked P450scc with an IC50 of 10 microM. AG significantly suppressed the baseline ACTH-R mRNA expression in a dose-dependent fashion (300 microM AG: 5% +/- 1%; 30 microM AG: 64% +/- 1%; 3 microM AG: 108% +/- 19% compared with control cells: 100% +/- 11%) but increased glucocorticoid receptor mRNA. The reduced ACTH-R mRNA was paralleled by low ACTH-induced cAMP accumulation indicating reduced expression of ACTH-R protein. The simultaneous incubation of hydrocortisone together with AG reversed the inhibitory effect of AG on the ACTH-R expression. AG and ETO inhibited cell proliferation in the NCI-h295 cells, but ETO was much more potent and showed antiproliferative effects at concentrations of 6 microM. The growth inhibition was not reversed by administration of hydrocortisone. CONCLUSIONS: Our data demonstrate that adrenostatic compounds not only act by suppression of steroidogenic enzymes but can also influence both ACTH-R expression and cell proliferation in adrenal cells. As these effects occur in vitro at concentrations that are reached during treatment with these drugs in patients, they are probably also of clinical relevance. Particularly the antiproliferative activity of ETO may be useful in Cushing's syndrome due to adrenocortical cancer. The interaction of steroidogenesis, ACTH-R and glucocorticoid receptor expression as well as cell proliferation provides a new concept of the intra-adrenal response to stress in humans.

Adrenal Cortex Neoplasms↗

PubMed2000

Metabolism of glucocorticoids and mineralocorticoids in patients with adrenal incidentalomas.

BACKGROUND: Adrenal incidentalomas are mostly nonfunctioning adrenocortical adenomas (NFI). However, in 5%-12% of the patients a preclinical Cushing's syndrome (PCS) with autonomous cortisol production by the tumour is present. Since urinary free cortisol excretion is not sensitive enough to determine subclinical hypercortisolism, in the present study more sensitive indicators of daily cortisol production were measured. DESIGN: (1) Tetrahydrocortisol, tetrahydrocortisone, urinary free cortisone together with urinary free cortisol were measured in 35 patients with adrenal incidentalomas (29 NFI and six PCS) and in 35 healthy controls. (2) Since little is known about daily aldosterone production, aldosterone metabolite excretions were measured. (3) As recently reported, ACTH stimulation revealed an increased response of precursors of the glucocorticoid and mineralocorticoid pathway. To find out which steroidogenic enzymes have altered activities, a 1-24ACTH stimulation test (250 microg i.v.) was carried out in 25 patients and 18 healthy controls with determination of multiple steroids. (4) Finally, since it was assumed that 21-hydroxylase deficiency or even 11b-hydroxylase deficiency may be involved in adrenal tumourigenesis, the prevalence of germline CYP21B and CYP11B1 mutations were studied in the same patients, who had underwent the ACTH stimulation test. RESULTS: (1) Glucocorticoid metabolites were within the normal range in all but three patients with NFI. As a group, the patients had subtle alterations in cortisol metabolism. Tetrahydrocortisol excretion was elevated in NFI and PCS compared with normal subjects (2.1 +/- 0.2 and 2.5 +/- 0.5 vs. 1.5 +/- 0.1 mg 24 h(-1); P < 0.05). Accordingly, the twofold elevation of the tetrahydrocortisol/free cortisol ratio indicates an increased 5beta-reduction of cortisol in the liver. (2) Tetrahydroaldosterone and aldosterone-18-glucuronide excretions were not different to controls. (3) In patients with incidentalomas an increased response to ACTH was seen for 17-hydroxyprogesterone (595 +/- 133 vs. 160 +/- 25 ng dL(-1)), 21-desoxycortisol (105 +/- 25 vs. 29 +/- 9 ng dL(-1)) and 11-desoxycortisol (401 +/- 40 vs. 293 +/- 17 ng dL(-1)). (4) In only one of 25 patients, a heterozygous deletion in exon 3 of the CYP21B gene was detected. CONCLUSIONS: (1) In conclusion, even the excretion of the main glucocorticoid metabolites is not a marker sensitive enough to distinguish between NFI and PCS. However, it is also possible that alterations in cortisol secretion are qualitative rather than quantitative. (2) Zona glomerulosa function is not influenced. (3) The elevation of 21-desoxycortisol argues against an impairment of 11beta-hydroxylase and favours a decreased activity of 21-hydroxylase. All others had wild-type sequences of both genes. (4) In conclusion, neither 21-hydroxylase deficiency nor 11beta-hydroxylase deficiency are predisposing factors for adrenal tumourigenesis.

Adenoma↗

PubMed2000

Erdheim-Chester disease: evidence for a disease entity different from Langerhans cell histiocytosis? Three cases with detailed radiological and immunohistochemical analysis.

Erdheim-Chester (EC) disease is a rare pathological entity with a highly specific and characteristic pattern of radiographic bone changes. Histologically it resembles Langerhans cell histiocytosis (LCH), and it is still a matter of discussion whether EC disease is a distinct entity or a type of LCH. In this study, 3 cases of Erdheim-Chester disease were followed up over years and examined in detail both radiologically and immunohistochemically. All 3 cases showed the pathognomonic skeletal features for EC disease as well as an identical immunohistochemical phenotype quite different from LCH. Macrophages and Touton cells reacted strongly positive with the histiocytic marker CD 68, whereas staining with S100 and CD1a, markers for Langerhans cells, were negative. Both the immunohistochemical phenotype and the bone changes were clearly distinct from LCH.

Antigens, CD↗

PubMed2000

Angiostatic effects of suramin analogs in vitro.

Suramin analogs are polyanionic naphthylureas structurally related to suramin, an antitumor agent with a narrow therapeutic window. The angiostatic activities of suramin and 16 suramin analogs were investigated using an easily quantifiable in vitro angiogenesis system. In addition, the antiproliferative activities of the analogs were studied in four different human tumor cell lines and in porcine aortic endothelial cells. The suramin analogs encompassed two main structural variations, i.e. their molecular size, and the number and substitution pattern of the sulfonate groups. Some suramin analogs with a reduced number of sulfonate groups (NF062, NF289 and NF326) showed significant dose-dependent angiostatic and also antiproliferative activities. The disulfonate NF062 was superior to suramin in inhibiting HT29 and T47D tumor cells while demonstrating a similar angiostatic potential as suramin. Therefore, the sulfonate groups in the para position of the amino groups of the naphthyl residues of suramin seem to be of special importance. The very small disulfonates (NF108, NF109, NF499, NF500 and NF241) and the asymmetric compound NF520, one half of the suramin molecule, are inactive. Therefore, a minimal molecule size seems to be essential for the biological activity. Suramin is a rather rigid molecule. The highly flexible analogs (NF527, NF528 and NF529) are inactive. This indicates that the molecular rigidity is important for the biological activity.

Angiogenesis Inhibitors↗

PubMed2000

Steroidogenic acute regulatory protein mRNA expression in adrenal tumours.

The rate limiting step in steroidogenesis is cholesterol transport through the outer to the inner mitochondrial membrane and the cytochrome P450 side chain cleavage (P450scc) complex. The protein factor responsible for this transport, and as such necessary for regulating the acute production of steroids, has been identified and named the steroidogenic acute regulatory protein (StAR). We investigated the expression of StAR in functional and non-functional adrenal neoplasms and compared the expression with that of P450scc. Poly A RNA was extracted from normal adrenal glands (NAG, n=5), aldosterone producing adenomas (APA, n=4), cortisol producing adenomas (CPA, n=5), adrenocortical carcinomas (ACC, n=6) and non-functional adenomas (NFA, n=3), electrophoresed through a 1% agarose gel, blotted and hybridised with a PCR-generated cDNA labelled with [(32)P]CTP. The blots were stripped and re-hybridised with a P450scc cDNA and a mouse beta-actin probe. Compared with P450scc, StAR mRNA expression showed little variability in the magnitude of expression and did not correlate with the endocrine profiles (NAG: StAR 100+/-16%, P450scc 100+/-14%; APA: StAR 80+/-3%, P450scc 94+/-13%; CPA: StAR 71+/-10%, P450scc 109+/-15%; NFA: StAR 64+/-9.5%, P450scc 18+/-5%; means+/-s.e.m.). ACC expressed low levels of both genes probably as a result of dedifferentiation (StAR 29+/-9%, P450scc 46+/-18%). Incubation of the NCI-h295 tumour cell line with 10nmol ACTH and 10micromol forskolin induced an increase in the abundance of StAR and P450scc mRNA, demonstrating gene regulation by the cAMP protein kinase A pathway. Furthermore, we incubated the NCI-h295 tumour cell line with the adrenostatic compounds, aminoglutethimide and metyrapone. We could not detect an effect on the expression of StAR mRNA, whereas the expression of P450scc mRNA was significantly reduced. We conclude that, in contrast to P450scc, StAR seems to be evenly expressed in adrenocortical adenomas. Therefore, the endocrine activity of a given tumour cannot be explained by the abundance of StAR expression. In ACC, both StAR and P450scc expression is low, explaining the relatively inefficient steroid production of these tumours.

Adenoma↗

PubMed2000

Multiple endocrine neoplasia type 1 gene expression is normal in sporadic adrenocortical tumors.

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant disorder with neoplasia of the anterior pituitary, the parathyroid, the endocrine pancreas and other endocrine tissues including the adrenal cortex. The tumor-suppressor gene causing this disease was identified at the gene locus 11q13. We recently reported that adrenocortical carcinomas frequently show loss of heterozygosity (LOH) of 11q13, but do not contain point mutations within the MEN1-coding region. To investigate whether reduced gene expression (for example by mutations within the MEN1 promoter) may contribute to the tumorigenesis of sporadic adrenocortical tumors, 24 adrenocortical specimen were studied by Northern blot analysis. This series included six adrenocortical carcinomas, four cortisol-producing adenomas, six aldosterone-producing adenomas, three endocrine-inactive adenomas and six normal adrenal glands. The presence of LOH of 11q13 was investigated using five polymorphic microsatellite markers (D11S956, PYGM, D11S4939, D11S4946 and D11S987) close to the MEN1 gene. Poly-A mRNA was hybridized with a PCR-generated cDNA probe of the MEN1 gene, a cDNA of the former MEN1 candidate gene phospholipase (PLC) beta3 and a mouse beta-actin cDNA for normalization. LOH of 11q13 was detected in five out of six carcinomas and two inactive adenomas, but in none of the hormone-producing adenomas. Compared with normal adrenals (100+/-6. 5%, mean+/-s.e.m.) MEN1 mRNA in adrenocortical tumors was expressed in similar amounts (carcinomas 109+/-11%, cortisol-producing adenomas 131+/-10%, aldosterone-producing adenomas 113+/-13%, endocrine-inactive adenomas 111+/-2%) with the exception of one adrenocortical carcinoma with low MEN1 mRNA expression (66%). PLCbeta3 mRNA expression showed a variable pattern without reaching significant differences between the groups. We conclude that since mRNA levels were unaltered in the majority of tumors, mutations of the MEN1 gene causing altered gene transcription is unlikely to be a major pathogenic factor of sporadic adrenocortical tumors.

Adenoma↗

PubMed2000

Adrenocortical function in patients with macrometastases of the adrenal gland.

OBJECTIVE: Metastases of the adrenal gland are a frequent finding in patients with malignant tumors like bronchogenic carcinoma or breast cancer. Only limited and conflicting data on adrenocortical function in these patients are available. DESIGN: Cross-sectional study. METHODS: We investigated the impact of adrenal macrometastases on adrenocortical function in a series of 28 tumor patients using the ACTH(1-24) stimulation test and dexamethasone suppression test. Seven normal controls (Con), eleven patients without adrenal metastases (No Met), eight patients with unilateral (Uni Met) and nine patients with bilateral adrenal metastases (Bil Met) were investigated. RESULTS: The prevalence of adrenal insufficiency was low in our study population, with only two of nine patients with bilateral metastases having subclinical adrenocortical insufficiency. In the remaining patients with uni- or bilateral metastases, baseline and stimulated cortisol concentrations were higher than in controls and cancer patients without metastases (baseline cortisol (in nmol/l): Con: 307+/-33.2 vs Uni Met: 440+/-53.5, and Bil Met: 637.6+/-92.1, P=0.04 by ANOVA; cortisol 60 min after ACTH(1-24): Con: 794.6+/-41.2 vs Uni Met: 990.8+/-92.9, and Bil Met: 1151.4+/-155.5, P=0.03 by ANOVA). Simultaneously, baseline and stimulated serum aldosterone concentrations were significantly blunted in the tumor groups. CONCLUSIONS: Adrenal insufficiency is infrequent and develops only in patients with bilateral metastases. However, the majority of patients have activation of the hypothalamic-pituitary-adrenal axis despite adrenal metastases with strongly elevated cortisol concentrations.

Adrenal Cortex↗

PubMed2000

DHEA replacement in women with adrenal insufficiency--pharmacokinetics, bioconversion and clinical effects on well-being, sexuality and cognition.

Standard replacement for adrenal insufficiency (AI) consists of glucocorticoids and mineralocorticoids while DHEA deficiency is routinely ignored. Thus, AI represents the ideal pathophysiological model of isolated DHEA deficiency. We investigated the effects of DHEA replacement in 24 women with primary and secondary AI employing a double blind, placebo-controlled, randomized crossover design. A DHEA dose of 50 mg/d was chosen based on preceding single-dose pharmacokinetics and bioconversion studies. Each patient received four months of treatment with DHEA and four months placebo, with a one-month washout period. Measurements included serum steroid hormones, somatotropic parameters and psychometric assessment of well-being, mood, cognition and sexuality. Treatment with DHEA raised the initially low serum concentrations of DHEA, DHEAS, androstenedione, and testosterone into the normal range. DHEA induced a slight increase in serum IGF-I, but only in patients with primary AI, suggesting a growth hormone-mediated effect. DHEA treatment significantly improved overall wellbeing as well as scores for depression, anxiety, and their physical correlates. Furthermore, DHEA significantly increased both sexual interest and the level of satisfaction with sex. DHEA replacement had no influence on the cognitive performance, which was already on a high level at baseline. In conclusion, DHEA replacement improves well-being and sexuality in women with adrenal insufficiency. If this is due to a direct effect of DHEA on the brain, an indirect effect via increased androgen synthesis, or both, remains to be elucidated. Long-term studies in patients of both sexes are needed to further define the role of DHEA in standard replacement for adrenal insufficiency.

Adrenal Insufficiency↗

PubMed2000

Adrenocortical carcinoma is characterized by a high frequency of chromosomal gains and high-level amplifications.

Distinction of adrenocortical carcinoma from benign adrenocortical lesions by standard criteria is often difficult. In order to search for additional diagnostic parameters, a series of 25 adrenocortical tumors, 8 adenomas, 14 primary carcinomas, 1 metastasis, and the 2 adrenocortical carcinoma cell lines SW13 and NCI-H295 were analyzed by the approach of comparative genomic hybridization (CGH). Except for the two smallest adenomas, all tumors showed chromosomal imbalances with a high incidence of chromosomal gains, most frequently involving chromosomes or chromosome arms 5, 7, 8, 9q, 11q, 12q, 14q, 16, 17q, 19, 20, and 22q. The only significant loss of material concerned the distal part of 9p. Furthermore, 21 high-level amplifications were identified in 15 different regions of the genome. The consensus regions of recurrent gains and the focal high-level amplifications allowed identification of a series of chromosomal subregions containing candidate proto-oncogenes of potential pathogenic function in adrenocortical tumors: 1p34.3-pter, 1q22-q25, 3p24-pter, 3q29, 7p11.2-p14, 9q34, 11q12-11q13, 12q13, 12q24.3, 13q34, 14q11.2-q12, 14q32, 16p, 17q24-q25, 19p13.3, 19q13.4, and 22q11.2-q12. A subset of the CGH data was independently confirmed by interphase cytogenetics. Interestingly, the adenomas larger than 4 cm contained gained material of regions also overrepresented in carcinomas. In addition, several chromosomal gains, in particular the high-level amplifications, were exclusive for the malignant status of the tumors. These data indicate that the larger adrenal lesions need to be carefully considered in the diagnosis of adrenocortical tumors, and that genetic aberrations might provide useful markers for a better diagnostic differentiation.

Adolescent↗

PubMed2000

[Secondary prevention of osteoporosis and identification of high risk patients].

Low bone mass is a major determinant of bone fragility. With respect to hip fracture risk however, there is limited contribution of BMD to the exponential age-related increase in hip fracture incidence. Large prospective studies have identified a number of additional risk factors for hip fractures independent of bone density. These can be classified as skeletal factors and fall-related factors. Body height and hip axis length are positively correlated with fracture risk. Neuromuscular impairment with low gait speed, difficulty in doing a tandem walk, lower limb dysfunction, body sway or inability to rise from a chair without using one's arms predict future fracture risk. According to the concept of evidence-based medicine (EBM) preventive strategies are now available. Supplementation with calcium and vitamin D restores bone quality through suppression of secondary hyperparathyroidism and decreases the risk of falling through improvement of neuromuscular co-ordination and body sway. Treatment with the bisphosphonates alendronate and risedronate increase bone strength and result in a significant reduction of vertebral as well as non-vertebral fractures. Hip protectors absorb energy during a fall and reduce hip fracture risk by 56%. Risk factor based patient selection may improve the cost-effectiveness of therapy.

Bone Density↗