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Patients with growth hormone deficiency (GHD) have many clinical features in common with Cushing's syndrome (glucocorticoid excess) - notably visceral obesity, insulin resistance, muscle myopathy and increased vascular mortality. Within key metabolic tissues, 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) converts cortisone to the active glucocorticoid, cortisol (11-dehydrocorticosterone and corticosterone in rodents respectively), and thus amplifies local glucocorticoid action. We hypothesize that 11β-HSD1 expression is negatively regulated by growth hormone (GH), and that GHD patients have elevated 11β-HSD1 within key metabolic tissues (leading to increased intracellular cortisol generation) which contributes to the clinical features of this disease. To identify the impact of GH excess/resistance on 11β-HSD1 in vivo, we measured mRNA expression in key metabolic tissues of giant mice expressing the bovine GH (bGH) gene, dwarf mice with a disrupted GH receptor (GHRKO) gene and mice expressing a gene encoding a GH receptor antagonist (GHA). Additionally, we assessed urine steroid markers of 11β-HSD1 activity in both GHRKO and bGH animals. 11β-HSD1 expression was decreased in gastrocnemius muscle (0.43-fold, p < 0.05), subcutaneous adipose (0.53-fold, p < 0.05) and epididymal adipose tissue (0.40-fold, p < 0.05), but not liver, in bGH mice compared to WT controls. This was paralleled by an increased percentage of 11-DHC (inactive glucocorticoid) present in the urine of bGH mice compared to WT controls (2.5-fold, p < 0.01) - consistent with decreased systemic 11β-HSD1 activity. By contrast, expression of 11β-HSD1 was increased in the liver of GHRKO (2.7-fold, p < 0.05) and GHA mice (2.0-fold, p < 0.05) compared to WT controls, but not gastrocnemius muscle, subcutaneous adipose tissue or epididymal adipose tissue. In summary, we have demonstrated a negative relationship between GH action and 11β-HSD1 expression which appears to be tissue specific. These data provide evidence that increased intracellular cortisol production within key tissues may contribute to metabolic disease in GHD patients., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Recent studies suggest that vitamin D-deficiency is linked to increased risk of common human health problems. To define vitamin D 'status' most routine analytical methods quantify one particular vitamin D metabolite, 25-hydroxyvitamin D3 (25OHD3). However, vitamin D is characterized by complex metabolic pathways, and simultaneous measurement of multiple vitamin D metabolites may provide a more accurate interpretation of vitamin D status. To address this we developed a high-throughput liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to analyse multiple vitamin D analytes, with particular emphasis on the separation of epimer metabolites. A supportive liquid-liquid extraction (SLE) and LC-MS/MS method was developed to quantify 10 vitamin D metabolites as well as separation of an interfering 7α-hydroxy-4-cholesten-3-one (7αC4) isobar (precursor of bile acid), and validated by analysis of human serum samples. In a cohort of 116 healthy subjects, circulating concentrations of 25-hydroxyvitamin D3 (25OHD3), 3-epi-25-hydroxyvitamin D3 (3-epi-25OHD3), 24,25-dihydroxyvitamin D3 (24R,25(OH)2D3), 1,25-dihydroxyvitamin D3 (1α,25(OH)2D3), and 25-hydroxyvitamin D2 (25OHD2) were quantifiable using 220μL of serum, with 25OHD3 and 24R,25(OH)2D3 showing significant seasonal variations. This high-throughput LC-MS/MS method provides a novel strategy for assessing the impact of vitamin D on human health and disease., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Although the inhibitory effects of therapeutic glucocorticoids (GCs) on dendritic cells (DCs) are well established, the roles of endogenous GCs in DC homeostasis are less clear. A critical element regulating endogenous GC concentrations involves local conversion of inactive substrates to active 11-hydroxyglucocorticoids, a reduction reaction catalyzed within the endoplasmic reticulum by an enzyme complex containing 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1) and hexose-6-phosphate dehydrogenase (H6PDH). In this study, we found that this GC amplification pathway operates both constitutively and maximally in steady state murine DC populations and is unaffected by additional inflammatory stimuli. Under physiologic conditions, 11βHSD1-H6PDH increases the sensitivity of plasmacytoid DCs (pDCs) to GC-induced apoptosis and restricts the survival of this population through a cell-intrinsic mechanism. Upon CpG activation, the effects of enzyme activity are overridden, with pDCs becoming resistant to GCs and fully competent to release type I interferon. CD8α(+) DCs are also highly proficient in amplifying GC levels, leading to impaired maturation following toll-like receptor-mediated signaling. Indeed, pharmacologic inhibition of 11βHSD1 synergized with CpG to enhance specific T-cell responses following vaccination targeted to CD8α(+) DCs. In conclusion, amplification of endogenous GCs is a critical cell-autonomous mechanism for regulating the survival and functions of DCs in vivo.

Outcome data from large series confirm increased mortality of patients with pituitary tumours, predominantly due to vascular disease. Control of cortisol secretion and growth hormone (GH) hypersecretion (together with cardiovascular risk factor reduction) is key in the normalisation of mortality rates in patients with Cushing's disease and acromegaly, respectively, though some excess mortality may persist even in "cured" patients., (Copyright © 2012. Published by Elsevier Masson SAS.)

Glucocorticoids (GCs) are highly detrimental to skin integrity and function both when applied topically for anti-inflammatory treatments and during conditions of circulating excess, e.g., Cushing's syndrome. Within target tissues, GC availability is regulated at a prereceptor level, independently of systemic levels, by isozymes of 11β-hydroxysteroid dehydrogenase (11β-HSD) that interconvert active cortisol and inactive cortisone. Many of the adverse effects of GCs on skin are also reminiscent of the natural aging process. 11β-HSD1 (which activates cortisol), but not 11β-HSD2 (which inactivates cortisol), was expressed in epidermal keratinocytes and dermal fibroblasts in human skin and also in outer hair follicle root sheath cells in murine skin. 11β-HSD1 activity was present ex vivo in both species and increased with age in human skin tissue explants. In primary human dermal fibroblasts (HDF) from both photoprotected and photoexposed sites, 11β-HSD1 also increased with donor age. Additionally, photoexposed HDF displayed higher 11β-HSD1 mRNA expression than donor-matched photoprotected HDF. GC treatment of HDF caused upregulation of 11β-HSD1 mRNA levels independent of donor age or site. The age- and site-associated increase in dermal 11β-HSD1, and the ensuing increased local GC activation, may contribute to the adverse changes in skin morphology and function associated with chronological aging and photoaging.

The prevalence of primary hyperaldosteronism approaches 10% of all hypertensive patients, and besides efficient diagnostic procedures, effective treatment is of increasing importance to reverse increased morbidity and mortality. Aldosterone-producing adenoma and unilateral adrenal hyperplasia are amenable to cure by endoscopic adrenalectomy. Bilateral adrenal hyperplasia (micro- or macronodular), which comprises two-thirds of primary hyperaldosteronism, is treated primarily by mineralocorticoid receptor antagonists (starting dose 12.5-25mg/day spironolactone with titration up to 100mg/day, alternatively 50-100mg/day eplerenone). If blood pressure is not normalised by this first-line treatment, additional treatment with potassium-sparing diuretics (amiloride or triamterene) or calcium channel antagonists is necessary. The start of medication should be closely monitored by serum electrolyte and creatinine controls., (2010 Elsevier Ltd. All rights reserved.)

Background: Insulin-like growth factor I (IGF-1) is for the most part bound in a ternary complex with IGF-binding protein-3 (IGFBP-3) and acid-labile subunit (ALS). This ternary complex is a storage form of IGF-1 in blood and passes not through the renal glomerulus. Little information is available in regard to the components of the ternary complex in adult renal disease., Objective: To investigate levels of serum IGF-1, IGFBP-3 and ALS in relation to renal function and extent of proteinuria., Design and Patients: We measured IGF-1, IGFBP-3 and ALS concentrations in 137 patients who were investigated due to proteinuria and/or haematuria and/or renal impairment. The patients received renal biopsies and the histological diagnosis was documented. Urinary albumin excretion and relevant clinical parameter were evaluated., Results: IGF-1 showed a highly positive correlation to IGFBP-3 and ALS, and the latter to IGFBP-3. IGF-1, IGFBP-3 and ALS decreased with increasing age. IGF-1 and IGFBP-3 showed no significant change depending on the creatinine clearance. However, ALS decreased with decreasing renal function. In patients with heavy proteinuria ALS levels, but not IGF-1 and IGFBP-3 levels, decreased significantly. Patients with chronic ischaemic renal damage and diabetic glomerulopathy showed higher IGF-1 and IGFBP-3 levels compared to patients with thin glomerular basement membrane disease despite their older age., Conclusions: IGF-1 and IGFBP-3 levels seem to be independent of renal function and severity of proteinuria. However, ALS levels are altered in renal failure and nephrotic syndrome, which may be due to increased renal loss or diminished hepatic production or both., (Copyright (c) 2009 Elsevier Ltd. All rights reserved.)

Cushing's disease results from prolonged overexposure of tissues to endogenous glucocorticoids, secondary to adrenocorticotrophin excess from the pituitary. Common clinical signs and symptoms include weight gain, hypertension, and osteoporosis. Effective treatment of Cushing's disease can normalize biochemical levels, reverse comorbidities, and improve overall survival and quality of life. Treatment options include pituitary or adrenal surgery, radiotherapy, and various medical therapies, but each has important limitations. Medical therapies that effectively target the pituitary tumour are urgently needed., (Copyright 2009 Elsevier Ltd. All rights reserved.)

To examine any potential role for 1,25-dihydroxyvitamin D (1,25(OH)2D) in inflammation associated with chronic kidney disease we measured vitamin D metabolites, markers of inflammation and gene expression in 174 patients with a variety of kidney diseases. Urinary MCP-1 protein and renal macrophage infiltration were each significantly but inversely correlated with serum 1,25(OH)2D levels. Logistic regression analysis with urinary MCP-1 as binary outcome showed that a 10-unit increase in serum 1,25(OH)2D or 25OHD resulted in lower renal inflammation. Analysis of 111 renal biopsies found that renal injury was not associated with a compensatory increase in mRNA for the vitamin D-activating enzyme 25-hydroxyvitamin D-1alpha-hydroxylase (CYP27B1), its catabolic counterpart 24-hydroxylase, or the vitamin D receptor. There was, however, a significant association between tissue MCP-1 and CYP27B1. Patients with acute renal inflammation had a significant increase in urinary and tissue MCP-1, macrophage infiltration, and macrophage and renal epithelial CYP27B1 expression but significantly lower levels of serum 1,25(OH)2D in comparison to patients with chronic ischemic disease despite similar levels of renal damage. In vitro, 1,25(OH)2D attenuated TNFalpha-induced MCP-1 expression by human proximal tubule cells. Our study indicates that renal inflammation is associated with decreased serum vitamin D metabolites and involves activation of the paracrine/autocrine vitamin D system.

Data are presented on the urinary corticosteroid metabolic profile of the mouse strain 129/svJ. Through the use of GC/MS we have characterized, or tentatively identified corticosterone (Kendall's compound B) metabolites of both the 11beta-hydroxy and 11-carbonyl (compound A) series in urine. Full mass spectra of the methyloxime-trimethylether derivatives of 15 metabolites are included in the paper as an aid to other researchers in the field. Metabolites ranged in polarity from tetrahydrocorticosterone (THB) to dihydroxy-corticosterone with dominance of highly polar steroids. We found that prior to excretion corticosterone can undergo oxidation at position 11beta, reduction at position 20 and A-ring reduction. Metabolites retaining the 3-oxo-4-ene structure can be hydroxylated at position 6beta- as well as at an unidentified position, probably 16alpha-. Saturated steroids can be hydroxylated at positions 1beta-, 6alpha-, 15alpha- and 16alpha. A pair of hydroxy-20-dihydro-corticosterone metabolites (OH-DHB) were the most important excretory products accounting for about 40% of the total. One metabolite of this type was identified as 6beta-hydroxy-DHB; the other, of similar quantitative importance was probably 16alpha-hydroxy-DHB. The ratio of metabolites of corticosterone (B) to those of 11-dehydro-corticosterone (A) was greater than 9:1, considerably higher than that for the equivalent "human" ratio of 1:1 for cortisol to cortisone metabolites. Results from this study allowed the evaluation of 11beta-hydroxysteroid dehydrogenase (11beta-HSD) activity in mice with deleted glucose-6-phosphate transporter (G6PT). These mice had attenuated back-conversion of A to B resulting in an increased ratio of A-metabolites to B-metabolites [Walker EA, Ahmed A, Lavery GG, Tomlinson JW, Kim SY, Cooper MS, Stewart PM, 11beta-Hydroxysteroid dehydrogenase type 1 regulation by intracellular glucose-6-phosphate, provides evidence for a novel link between glucose metabolism and HPA axis function. J Biol Chem 2007;282:27030-6]. We believe this study is currently the most comprehensive on the urinary steroid metabolic profile of the mouse. Quantitatively less steroid is excreted in urine than in feces by this species but urine analysis is more straightforward and the hepatic metabolites are less subject to microbial degradation than if feces was analyzed.

The question addressed in this study was the nature of the enzyme required to remove the side-chain of 17-hydroxycorticosteroids, leading in the case of cortisol to the excretion of 11beta-hydroxyandrosterone, 11-oxo-androsterone and the corresponding etiocholanolones. We questioned whether it could be CYP17, the 17-hydroxylase/17,20-lyase utilized in androgen synthesis. The conversion of exogenous cortisol to C(19) steroids in patients with complete 17-hydroxylase deficiency (17HD) was studied rationalizing that if CYP17 was involved no C(19) steroids would be formed. The urinary excretion of the four 11-oxy-C(19) steroids as well as many of the major C(21) cortisol metabolites were measured by GC/MS. Our results showed that the conversion of cortisol to C(19) steroids was normal in 17HD indicating that a currently unidentified enzyme must be responsible for this transformation. A secondary goal was to determine to what extent 11-oxy-C(19) steroids were metabolites of cortisol or adrenal synthesized 11beta-hydroxyandrostenedione. Since cortisol-treated 17HD patients cannot produce androstenedione, all C(19) 11-oxy-metabolites excreted must be derived from exogenous cortisol. The extent to which 17HD patients have lower relative excretion of C(19) steroids should reflect the absence of 11beta-hydroxyandrostenedione metabolites. Our results showed almost all of 11-oxo-etiocholanolone and 11beta-hydroxyetiocholanolone were cortisol metabolites, but in contrast the excretion of 11beta-hydroxyandrosterone was less than 10% that of normal individuals, indicating that in excess of 90% must be a metabolite of 11beta-hydroxyandrostenedione.

Conclusive in vivo evidence regarding the enzyme responsible for steroid hormone 5beta-reduction has not been obtained, although studies have suggested it may be the same enzyme as that utilized for cholic acid and chenodeoxycholic bile-acid synthesis. We have recorded the steroid metabolome of a patient with a defect in the "bile-acid" 5beta-reductase (AKR1D1) and from this confirm that this enzyme is additionally responsible for steroid hormone metabolism. The 13-year old patient has been investigated since infancy because of a cholestasis phenotype caused by bile-acid insufficiency. Several years ago it was shown that she had a 662C>T missense mutation in AKR1D1 causing a Pro198Leu substitution. It was found that the patient had an almost total absence of 5beta-reduced metabolites of corticosteroids and severely reduced production of 5beta-reduced metabolites of other steroids. The patient is healthy in spite of her earlier hepatic failure and is on no treatment. All her vital signs were normal, as were results of many biochemical analyses. She had normal pubertal changes and experiences regular menstrual cycles. There was no evidence for any clinical condition that could be attributed to attenuated ability to metabolize steroids in normal fashion. Both parents were heterozygous for the mutation but the steroid excretion was entirely normal, although an older female sibling showed definitive evidence for attenuated 5beta-reduction of cortisol. A younger brother had a normal steroid metabolome. The sibling genotypes were not available.

Hypopituitarism is characterized by loss of function of the anterior pituitary gland. It is a rare condition that can present at any age and is caused by pathology of the hypothalamic-pituitary axis or one of many gene mutations. The symptoms and signs of hypopituitarism may evolve over several years and be nonspecific or related to the effects of the underlying disease process or to hormone deficiencies. Investigation of patients requires a combination of basal hormone levels and dynamic function tests; management requires regular monitoring. The goal of physicians managing patients who have hypopituitarism is to improve their health and long-term outcome.

The global epidemic of obesity and type-2 diabetes has heightened the need to understand the mechanisms that contribute to its pathogenesis and also to design and trial novel treatments. Patients with glucocorticoid (GC) excess--'Cushing's syndrome'--are phenotypically similar to patients with simple obesity. As such, much research has focused on the manipulation of local GC action as a therapeutic strategy. The majority of the classical actions of GCs are mediated via activation of the glucocorticoid receptor (GR). 11beta-Hydroxysteroid dehydrogenase type 1 (11beta-HSD1) converts inactive cortisone to cortisol and therefore amplifies local GC action. There is now a wealth of data from rodent and clinical studies implicating this conversion in the pathogenesis of obesity, type-2 diabetes, and the metabolic syndrome. Selective 11beta-HSD1 inhibitors (selective in that they block the activity of 11beta-HSD1 and not 11beta-HSD2 which inactivates cortisone to cortisol in mineralocorticoid target tissues) are currently in development although not yet available for use in clinical studies. Rodent studies utilizing these compounds have shown dramatic improvements in insulin sensitivity as well as improvements in lipid profiles and atherogenesis. A further experimental approach has been to design drugs that antagonize GR activation, and again these compounds appear to improve insulin sensitivity and lower glucose production rates. The key test for both of these research strategies is whether they will translate into clinical studies, and results from these trials are now eagerly awaited.

Corticosteroids are critically involved in blood pressure regulation. Lack of adrenal steroids in Addison's disease causes life-threatening hypotension, whereas glucocorticoid excess in Cushing's syndrome invariably results in high blood pressure. At a pre-receptor level, glucocorticoid action is modulated by 11beta-hydroxysteroid dehydrogenases (11beta-HSDs). 11Beta-HSD1 activates cortisone to cortisol to facilitate glucocorticoid receptor (GR)-mediated action. By contrast, 11beta-HSD2 plays a pivotal role in aldosterone target tissues where it catalyses the opposite reaction (i.e. inactivation of cortisol to cortisone) to prevent activation of the mineralocorticoid receptor (MR) by cortisol. Mutations in the 11beta-HSD2 gene cause a rare form of inherited hypertension, the syndrome of apparent mineralocorticoid excess (AME), in which cortisol activates the MR resulting in severe hypertension and hypokalemia. Ingestion of competitive inhibitors of 11beta-HSD2 such as liquorice and carbenoxolone result in a similar but milder clinical phenotype. Epidemiological data suggests that polymorphic variability in the HSD11B2 gene determines salt sensitivity in the general population, which is a key predisposing factor to adult onset hypertension in some patients. Extrarenal sites of glucocorticoid action and metabolism that might impact on blood pressure include the vasculature and the central nervous system. Intriguingly, increased exposure to glucocorticoids during fetal life promotes high blood pressure in adulthood suggesting an early programming effect. Thus, metabolism and action in many peripheral tissues might contribute to the pathophysiology of human hypertension.

Adrenal corticosteroids are essential for life, and an appreciation of the mechanisms underpinning their synthesis, secretion, and mode of action in normal physiology is essential if the physician is to diagnose and treat patients who have Cushing's syndromes effectively. In each case, there have been clinically significant advances in the knowledge base over recent years, notably in the understanding of steroidogenesis, cortisol action, and metabolism. This article describes corticosteroid biosynthesis, metabolism, and action.

Background: Congenital adrenal hyperplasia with apparent combined P450C17 and P450C21 deficiency is associated with accumulation of steroid metabolites, indicating impaired activity of 17alpha-hydroxylase and 21-hydroxylase. However, no mutations have been reported in the CYP17 and CYP21 genes, which encode these P450 enzymes. Affected girls are born with ambiguous genitalia, but their circulating androgens are low, and virilisation does not progress. We aimed to investigate the underlying molecular basis of congenital adrenal hyperplasia with apparent combined P450C17 and P450C21 deficiency in affected children., Methods: We did sequence analysis of the human gene encoding P450 oxidoreductase, an enzyme that is important in electron transfer from NADPH to P450C17 and P450C21. We studied two unrelated families with a total of three affected children and 100 healthy controls. Wild-type and mutant P450 oxidoreductase proteins were bacterially expressed, purified, and assayed for cytochrome c reductase activity., Findings: We identified four mutations encoding single aminoacid changes in P450 oxidoreductase. All patients were compound heterozygotes, whereas their parents and an unaffected sibling harboured a mutation in only one allele. By contrast, no mutations were noted in the controls. Bacterial expression of recombinant mutant proteins revealed deficient or reduced enzyme activity., Interpretation: Molecular pathogenesis of this form of congenital adrenal hyperplasia is caused by mutations in the gene encoding P450 oxidoreductase. Deficiency of this enzyme could suggest an alternative pathway in human androgen synthesis, present only in fetal life, which explains the combination of antenatal androgen excess and postnatal androgen deficiency.

In addition to its classical calciotropic effects, the active form of vitamin D, 1,25-dihydroxyvitamin D(3) (1,25(OH)(2)D(3)) is a potent anti-proliferative/immunomodulatory secosteroid. The enzyme that catalyzes the synthesis of 1,25(OH)(2)D(3), 1alpha-hydroxylase (1alpha-OHase), is expressed in many human tissues, highlighting its possible role as an autocrine/paracrine activator of vitamin D. Immunohistochemical and RNA analyses were used to characterize the ontogeny of 1alpha-OHase expression in human placenta and decidua. Protein for 1alpha-OHase was detectable in trophoblast and decidua; the latter being stronger in decidualized stromal cells than macrophages, with no staining of lymphocytes. Quantitative reverse transcriptase-polymerase chain reaction was used to assess changes in mRNA expression for 1alpha-OHase at different gestations: first (mean, 9.1 +/- 1.5 weeks); second (mean, 14 +/- 1.8 weeks), and third trimester (mean, 39.3 +/- 2.5 weeks). 1alpha-OHase expression in decidua was approximately 1000-fold higher in first (95% confidence limits, 611 to 1376) and second (95% confidence limits, 633 to 1623) trimester biopsies when compared with the third trimester (95% confidence limits, 0.36 to 2.81) (both P < 0.001). In placenta, 1alpha-OHase expression was 80-fold higher in the first (range, 42 to 137) and second (range, 30 to 199) trimester when compared with third trimester biopsies (0.6 to 1.6) (both P < 0.001). Similar results were obtained by semiquantitative IHC. Parallel analysis of the receptor for 1,25(OH)(2)D(3) (vitamin D receptor) indicated that, as with 1alpha-OHase, highest levels of expression occurred in first trimester decidua. However, changes in vitamin D receptor mRNA expression across gestation were less pronounced than 1alpha-OHase. These spatiotemporal data emphasize the potential importance of 1alpha-OHase during early fetoplacental life and, in particular, suggest an autocrine/paracrine immunomodulatory function for the enzyme.

Background: Pegvisomant is a new growth hormone receptor antagonist that improves symptoms and normalises insulin-like growth factor-1 (IGF-1) in a high proportion of patients with acromegaly treated for up to 12 weeks. We assessed the effects of pegvisomant in 160 patients with acromegaly treated for an average of 425 days., Methods: Treatment efficacy was assessed by measuring changes in tumour volume by magnetic resonance imaging, and serum growth hormone and IGF-1 concentrations in 152 patients who received pegvisomant by daily subcutaneous injection for up to 18 months. The safety analysis included 160 patients some of whom received weekly injections and are excluded from the efficacy analysis., Findings: Mean serum IGF-1 concentrations fell by at least 50%: 467 mg/L (SE 24), 526 mg/L (29), and 523 mg/L (40) in patients treated for 6, 12 and 18 months, respectively (p<0.001), whereas growth hormone increased by 12.5 mg/L (2.1), 12.5 mg/L (3.0), and 14.2 mg/L (5.7) (p<0.001). Of the patients treated for 12 months or more, 87 of 90 (97%) achieved a normal serum IGF-1 concentration. In patients withdrawn from pegvisomant (n=45), serum growth hormone concentrations were 8.0 mg/L (2.5) at baseline, rose to 15.2 mg/L (2.4) on drug, and fell back within 30 days of withdrawal to 8.3 mg/L (2.7). Antibodies to growth hormone were detected in 27 (16.9%) of patients, but no tachyphylaxis was seen. Serum insulin and glucose concentrations were significantly decreased (p<0.05). Two patients experienced progressive growth of their pituitary tumours, and two other patients had increased alanine and asparate aminotransferase concentrations requiring withdrawal from treatment. Mean pituitary tumour volume in 131 patients followed for a mean of 11.46 months (0.70) decreased by 0.033 cm(3) (0.057; p=0.353)., Interpretation: Pegvisomant is an effective medical treatment for acromegaly.

Background: Recent studies have shown that renal expression of 25-hydroxyvitamin D3-1alpha-hydroxylase (1alpha-OHase) is not restricted to proximal tubules. To investigate the significance of this expression, we characterized the regulation of 1alpha-OHase expression and activity in a human cortical collecting duct cell line (HCD)., Methods: Expression of 1alpha-OHase mRNA and protein was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot analyses. Enzyme activity was quantified using 25-hydroxyvitamin D3 as the substrate; conversion to 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and 24,25-dihydroxyvitamin D3 was then determined by thin-layer chromatography., Results: HCD cells expressed mRNA and protein for 1alpha-OHase. However, basal 1,25(OH)2D3 production was lower than that observed in proximal tubule HKC-8 cells. In both cell lines, synthesis of 1,25(OH)2D3 was increased by forskolin, parathyroid hormone, and low calcium medium. Conversely, treatment with 1,25(OH)2D3 itself decreased 1alpha-OHase activity. This effect was more pronounced in HCD cells, which also demonstrated significantly higher levels of 24-hydroxylase activity. The most striking induction of 1alpha-OHase activity was observed in the HCD cells following incubation with lipopolysaccharide, which was coincident with the expression of mRNA for both CD14 and Toll-like receptor 4., Conclusions: These results highlight the capacity for synthesis of 1,25(OH)2D3 in cells from more distal areas of the nephron. However, more sensitive feedback regulation and immune induction of 1alpha-OHase in the HCD cells suggest a more localized role for 1,25(OH)2D3 production in the distal nephron.

Two isoforms of the enzyme 11beta-hydroxysteroid dehydrogenase (11beta-HSD) interconvert the active glucocorticoid, cortisol, and inactive cortisone. 11beta-HSD1 is believed to act in vivo predominantly as an oxo-reductase using NADP(H) as a cofactor to generate cortisol. In contrast, 11beta-HSD2 acts exclusively as an NAD-dependent dehydrogenase inactivating cortisol to cortisone, thereby protecting the mineralocorticoid receptor from occupation by cortisol. In peripheral tissues, both enzymes serve to control the availability of cortisol to bind to the corticosteroid receptors. Defective expression of 11beta-HSD2 is implicated in patients with hypertension and intra-uterine growth retardation, while 11beta-HSD1 appears to be intricately involved in the conditions of apparent cortisone reductase deficiency, insulin resistance and visceral obesity. The ability of peripheral tissues to regulate corticosteroid concentrations through 11beta-HSD isozymes is established as an important mechanism in the pathogenesis of diverse human diseases. Modulation of enzyme activity may offer a novel therapeutic approach to treating human disease while circumventing the consequences of systemic glucocorticoid excess or deficiency., (Copyright 2001 Harcourt Publishers Ltd.)

Background: Four retrospective studies have reported premature mortality in patients with hypopituitarism with standard mortality ratios (SMRs) varying between 1.20 and 2.17. Patients with hypopituitarism have complex endocrine deficiencies, and the mechanisms underpinning any excess mortality are unknown. Furthermore, the suggestion has emerged that endogenous growth-hormone deficiency might account for any excess mortality. We aimed to clarify these issues by doing a large prospective study of total and specific-cause mortality in patients with hypopituitarism., Methods: We followed up 1014 UK patients (514 men, 500 women) with hypopituitarism from January, 1992, to January, 2000. 573 (57%) patients had non-functioning adenomas, 118 (12%) craniopharyngiomas, and 93 (9%) prolactinomas. SMRs were calculated as the ratio of observed deaths to the number of deaths in an age-matched and sex-matched UK population., Findings: The number of observed deaths was 181 compared with the 96.7 expected (SMR 1.87 [99% CI 1.62-2.16], p<0.0001). Univariate analysis indicated that mortality was higher in women (2.29 [1.86-2.82]) than men (1.57 [1.28-1.93], p=0.002), in younger patients, in patients with an underlying diagnosis of craniopharyngioma (9.28 [5.84-14.75] vs 1.61 [1.30-1.99], p<0.0001), and in the 353 patients treated with radiotherapy (2.32 [1.71-3.14] vs 1.66 [1.30-2.13], p=0.004). Excess mortality was attributed to cardiovascular (1.82 [1.30-2.54], p<0.0001), respiratory (2.66 [1.72-4.11], p<0.0001), and cerebrovascular (2.44 [1.58-4.18], p<0.0001) causes. There was no effect of hormonal deficiency on mortality, except for gonadotropin deficiency, which, if untreated was associated with excess mortality (untreated 2.97 [2.13-4.13] vs treated 1.42 [0.97-2.07], p<0.0001). Multiple regression analyses identified age at diagnosis, sex, a diagnosis of craniopharyngioma, and untreated gonadotropin deficiency as independent significant factors affecting mortality., Interpretation: Patients with hypopituitarism have excess mortality, predominantly from vascular and respiratory disease. Age at diagnosis, female sex, and above all, craniopharyngioma were significant independent risk factors. Specific endocrine-axis deficiency, with the exception of untreated gonadotropin deficiency, does not seem to have a role.

Fluorimetric studies on progesterone-induced [Ca(2+)](i) signalling in mammalian spermatozoa show both the well-characterised [Ca(2+)](i) transient and a subsequent sustained phase. However, the sustained phase is thought to reflect release of the fluorochrome during the acrosome reaction and has not been subject to critical investigation. We have used single-cell imaging of [Ca(2+)](i) to analyse the progesterone-induced [Ca(2+)](i) response in large numbers (>2000) of capacitated, human spermatozoa. In 70% of cells, treatment with progesterone induced a transient increase, which typically peaked within 1 min and decayed with a similar time course. Upon rapid application of progesterone this response peaked within 5-20 s. In 35% of progesterone-treated spermatozoa a sustained elevation of [Ca(2+)](i) occurred, which became discernible during the falling phase of the transient response and persisted for at least 20 min. Both [Ca(2+)](i) responses were localised to the postacrosomal region. Averaging of large numbers of single cell responses generated traces similar to those seen in fluorimetric studies. Although the sustained response was strongly associated with the initial, transient response, a few spermatozoa generated sustained responses that were not preceded by a significant transient response (5% of cells). It is concluded that a genuine biphasic [Ca(2+)](i) signal is activated by progesterone and that the sustained response is a discrete signalling event with biological significance., (Copyright 2000 Academic Press.)

Hypertension with hypokalaemia and suppression of plasma renin activity is known as mineralocorticoid hypertension. Although mineralocorticoid hypertension accounts for a small number of patients labelled as having "essential" hypertension, it is a potentially reversible cause of high blood pressure. The most common cause of mineralocorticoid hypertension is probably primary aldosteronism; controlled posture studies to measure plasma renin activity and aldosterone concentrations, followed by adrenal imaging, will ensure the differential diagnosis between an aldosterone-producing adenoma and idiopathic adrenal hyperplasia in most cases. Three monogenic forms of mineralocorticoid hypertension have been described: glucocorticoid-suppressible hyperaldosteronism, Liddle's syndrome, and apparent mineralocorticoid excess, which have provided new insights into mineralocorticoid hormone action. Many patients with mineralocorticoid-based hypertension are now known to have normal serum potassium concentrations. Until the true prevalence of primary aldosteronism and monogenic forms of mineralocorticoid hypertension are defined, a high index of suspicion is needed in every hypertensive patient. Hypertensive patients with hypokalaemia, together with those with severe hypertension or a family history of hypertension or stroke, should be screened for mineralocorticoid excess.

This study investigates the regulation of the insulin-like growth factors (IGFs) and their regulatory proteins in 14 critically ill patients during the 30-day period following admission to an intensive care unit (ICU). Levels of IGF-I, IGF-II, IGF binding protein-3 (IGFBP-3) and acid-labile subunit (ALS) were low on admission, and in the 8 patients whose serum IGF-I levels failed to increase over 30 days, levels of the other proteins also remained low, while IGFBP-3 proteolytic activity increased. Of these proteins, ALS correlated best with serum levels of nutritional indicators, particularly prealbumin. IGFBP-2 and IGFBP-6 levels tended to be high in critically ill patients, but showed little change over the 30-day period. In contrast, IGFBP-1 levels were high on admission, correlated with early changes in nitrogen balance, and fell rapidly during the first week. By demonstrating that the IGF-I response in ICU patients is related to changes in the IGF regulatory proteins, this study may be of value in planning therapeutic intervention using growth hormone or IGF-I.

Background: Central obesity results in a cluster of metabolic abnormalities contributing to premature death. Glucocorticoids regulate adipose-tissue differentiation, function, and distribution, and in excess, cause central obesity. Glucocorticoid hormone action is, in part, controlled by two isoforms of the enzyme 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) which interconverts hormonally active cortisol to inactive cortisone. We studied cortisol metabolism within different adipose tissue depots., Methods: We analysed expression and activity of the two isoforms (1 and 2) of 11 beta-HSD in cultured omental and subcutaneous adipose stromal cells from 16 patients undergoing elective abdominal surgery., Findings: Only the type 1 isoform (11 beta-HSD1) was expressed in adipose stromal cells. The predominant activity was oxo-reductase (conversion of cortisone to cortisol greater than cortisol to cortisone) and was higher in omental than subcutaneous fat (cortisone to cortisol, median 57.6 pmol mg-1 h-1 [95% CI 25.8-112.9] vs 0 pmol mg-1 h-1 [0-0.6], p < 0.001). 11 beta-HSD1 oxo-reductase activity was further increased (127.5 pmol mg-1 h-1 [82.1-209], p < 0.05) when omental adipose stromal cells were treated with cortisol and insulin., Interpretation: Adipose stromal cells from omental fat, but not subcutaneous fat, can generate active cortisol from inactive cortisone through the expression of 11 beta-HSD1. The expression of this enzyme is increased further after exposure to cortisol and insulin. In vivo, such a mechanism would ensure a constant exposure of glucocorticoid specifically to omental adipose tissue, suggesting that central obesity may reflect "Cushing's disease of the omentum".

The type 1 and type 2 isoforms of human 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) play a crucial role, respectively, in modulating glucocorticoid and mineralocorticoid hormone action. Deficiency of the 11 beta-HSD2 isoform, as described in the syndrome of apparent mineralocorticoid excess and following liquorice (glycyrrhetinic acid) or carbenoxolone ingestion, results in hypertension in which cortisol acts as a potent mineralocorticoid. Several studies have addressed the effects of progesterone, glycyrrhetinic acid, and their derivatives on 11 beta-HSD activity, but these were largely undertaken before the characterization of the 11 beta-HSD isoforms. The aim of this study was to evaluate the localization of 11 beta-HSD2 in human kidney and to study the effects of progesterone, glycyrrhetinic acid, and their related compounds on stable transfectants of the human 11 beta-HSD isoforms. Using an in-house sheep antibody against human 11 beta-HSD2, immunoperoxidase studies localized 11 beta-HSD2 to renal cortical and medullary collecting ducts. Glomeruli, vascular structures, loops of Henle, and proximal tubules were all negative. Confocal laser microscopy studies indicated both a cytoplasmic and nuclear localization for the enzyme within renal collecting ducts. The nuclear staining, which was intranuclear and was not associated with the nuclear membrane, accounted for 40% of the total cellular 11 beta-HSD2 immunoreactivity. Kinetic analysis of 11 beta-HSD activity in fetal kidney 293 cells stably transfected with h11 beta-HSD1/pcDNA3 or 11 beta-HSD2/pCR3, indicated, respectively, low-affinity dehydrogenase/oxoreductase activity (Km for F, 1.8 microM; Km for E, 270 nM) and high-affinity dehydrogenase activity (Km for F, 190 nM). The reductase activity of 11 beta-HSD1 was inhibited by 11 alpha-hydroxyprogesterone > carbenoxolone = glycyrrhetinic acid = progesterone > 11 beta-hydroxyprogesterone. The dehydrogenase activity of 11 beta-HSD2 was inhibited 11 alpha-hydroxyprogesterone = 11 beta-hydroxyprogesterone > glycyrrhetinic acid > carbenoxolone = progesterone. 11 beta-HSD2, expressed in the renal collecting duct, serves to protect the mineralocorticoid receptor (MR) in an autocrine fashion. The demonstration of a nuclear localization for what was thought to be principally a microsomal enzyme suggests that interaction between the MR and its ligand (either aldosterone or cortisol) may be a nuclear rather than a cytoplasmic event. The inhibitory effects of progesterone, glycyrrhetinic acid, and related compounds on 11 beta-HSD1 and 2 were similar, and it remains to be seen what implication these findings have for 11 beta-HSD1 action in tissues such as the liver and gonad and renal 11 beta-HSD2 activity in relation to sodium homeostasis and blood pressure control.

The syndrome of apparent mineralocorticoid excess (AME) is a heritable form of hypertension due to an inborn error of cortisol metabolism and is characterized by hypokalemia and low renin levels despite subnormal or normal levels of aldosterone and other known mineralocorticoids. The syndrome is attributable to congenital deficiency of the enzyme 11 beta-hydroxydehydrogenase (11 beta-HSD), which converts cortisol (F) to biologically inactive cortisone. This results in a prolonged half-life of F, which acts at the kidney level as a potent mineralocorticoid (MC). In fact, both F and aldosterone have similar affinities in vitro for type I MC receptor (MR), and 11 beta-HSD activity protects the MR in vivo from the higher circulating levels of F. The biochemical marker of this disorder is an increased ratio of tetrahydrocortisol (THF) + allo-THF/tetrahydrocortisone (THE) in the urine, which has been found in more than 20 patients described to date, together with evidence of a more general defect in steroid ring A reduction. Only a few cases (the so-called type II form) described in Italy differ from the classic form having a normal THF/THE ratio, but in both forms the ratio of free urinary F/E has recently been found to be similarly high. Dexamethasone is the treatment of choice but is often inadequate in long term control of high blood pressure. Acquired forms of AME are those consequent on abuse of licorice or carbenoxolone, which both inhibit 11 beta-HSD; the latter also inhibits the reverse 11-oxoreductase reaction leading to somewhat different abnormalities of urinary cortisol/cortisone. So far, two isoenzymes of 11 beta-HSD have been purified and cloned; 11 beta-HSD type 1 is NADP-dependent, abundant in liver, lung, and testis, and catalyzes both 11 beta-dehydrogenation and 11 beta-oxoreduction; no mutation in its gene was detected in patients with AME. A second NAD-dependent isoenzyme is present in kidney and placenta and catalyzes dehydrogenation only. Very recently (1995) two groups have independently demonstrated the presence of mutations in its gene, located in chromosome 16q22. New and co-workers found a point mutation in exon 6 of two affected siblings of an Iranian family, while White and co-workers in parallel studies showed point mutations or small deletions in both alleles in nine unrelated patients; importantly, expression studies showed minimal or absent activity for almost all the mutant sequences. No definite mutations have been so far identified in patients with AME type II. AME is thus the third single gene cause of human hypertension to be described, after glucocorticoid remediable aldosteronism in 1992 and Liddle's syndrome in 1994.

Background: 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) catalyses the interconversion of hormonally active cortisol to inactive cortisone and is vital for dictating specificity for the mineralocorticoid receptor. Thus, in patients with congenital deficiency of 11 beta-HSD (the syndrome of apparent mineralocorticoid excess, AME), cortisol and not aldosterone acts as a mineralocorticoid, resulting in hypertension and hypokalaemia with suppression of the renin-angiotensin-aldosterone axis. Two isoforms of human 11 beta-HSD have been described, but it is the NAD-dependent type 2 isoform (11 beta-HSD2), first characterised in placental tissue, that is expressed in the mineralocorticoid target tissues, kidney and colon. We have analysed the 11 beta-HSD2 gene as a candidate gene in explaining the molecular basis of AME., Methods: By exon-specific PCR-amplification of the 11 beta-HSD2 gene in a consanguineous kindred with AME, we found a point mutation (C1228T) in two affected siblings, and also in placental DNA obtained from a stillbirth pregnancy., Findings: The mutation in exon 5 of the 11 beta-HSD2 gene resulted in a premature stop site at codon 374 instead of a normal arginine (R374X), with the deletion of 32 aminoacids from the C-terminus of the 11 beta-HSD2 enzyme protein. Both parents, who are phenotypically normal, are heterozygote for the C1228T mutation in keeping with an autosomal recessive form of inheritance. NAD-dependent 11 beta-HSD activity was severely attenuated in the stillbirth placenta compared with control placental tissue, and no 11 beta-HSD immunostaining was observed in this placenta with antisera derived against a C-terminal 11 beta-HSD2 peptide sequence., Interpretation: AME is due to a mutation in the 11 beta-HSD2 gene, and is an example of human hypertension arising from a single gene defect.

11 beta-hydroxysteroid dehydrogenase (11 beta-HSD), by converting cortisol and corticosterone to hormonally inactive cortisone and 11-dehydrocorticosterone, respectively, is an important pre-receptor signaling pathway for the renal mineralocorticoid receptor (MR). This receptor has an equal affinity for the glucocorticoids, cortisol and corticosterone, and for the mineralocorticoid, aldosterone. In states of 11 beta-HSD deficiency such as the syndrome of apparent mineralocorticoid excess (AME) and licorice ingestion, cortisol acts as a potent mineralocorticoid. In addition to the established and cloned type I 11 beta-HSD, a second 11 beta-HSD isoform has been reported in rabbit kidney and human placenta. We have analyzed the kinetics of 11 beta-HSD activity in human kidney and compared it with the expressed human type I 11 beta-HSD cDNA. Microsomes were prepared from mid-gestational human fetal kidneys and incubated with various concentrations of cortisol (0.0125-10 microM) and NAD or NADP. Kinetic analysis revealed a high affinity (apparent Km 60 nM) isoform, the activity of which was exclusively NAD-dependent. No convincing NADP-dependent activity was seen. Similarly with cortisone as a substrate no 11-oxoreductase activity was evident. In contrast, when type I human 11 beta-HSD was ligated into the expression vector pcDNAI and transiently transfected into COS-I cells, low affinity (apparent Km 2.1 microM) NADP-dependent activity was seen. 11-Oxoreductase activity was also observed. The cloned type I human 11 beta-HSD encodes an enzyme with both low-affinity, NADP-dependent, dehydrogenase and 11-oxoreductase activities, but this activity is absent in human fetal kidney (and probably adult kidney).(ABSTRACT TRUNCATED AT 250 WORDS)

In normal physiology 11 beta-hydroxysteroid dehydrogenase (11 beta-OHSD) protects the mineralocorticoid receptor (MR) from glucocorticoid excess. In the rat, however, 11 beta-OHSD mRNA and activity is widespread, suggesting that it may also play a role in regulating ligand access to the glucocorticoid receptor (GR). We have studied the role of the 11 beta-OHSD in modulating corticosteroid hormone action in rat pituitary GH3 cells (glucocorticoids inhibit prolactin gene transcription) and renal epithelial NRK-52E cells (mineralocorticoids increase Na-K ATPase subunit gene expression) in culture. Both cell lines express high levels of 11 beta-OHSD activity, and Northern/Western blot analyses using a rat cDNA probe and antisera raised against rat liver 11 beta-OHSD reveal a single 1.4 Kb mRNA encoding an enzyme of molecular size 34 kDa. In GH3 cells, prolactin gene transcription was unaffected by corticosterone (B) in doses of 10(-8) to 10(-6) M. When 11 beta-OHSD activity was inhibited with the licorice derivative, glycyrrhetinic acid (GE); however, 10(-6) M B inhibited prolactin (PRL) mRNA levels to the same degree as an equimolar concentration of the GR agonist RU 28362. This effect was blocked by co-incubation with the GR antagonist RU 38486. In NRK-52E cells, co-incubation with B and GE resulted in a marked increase in alpha 1/beta 1 Na-K ATPase subunit mRNA levels when compared with GE and/or B alone and this effect could be blocked by administration of the MR antagonist RU 26752.(ABSTRACT TRUNCATED AT 250 WORDS)

Body fat and total body nitrogen (TBN) were quantified before and after refeeding in 32 female anorexia nervosa patients and in 29 matched control subjects by using the techniques of anthropometry and in vivo neutron-capture analysis (IVNCA). Mean body weight of patients (mean body mass index; BMI, in kg/m2), 15.4 +/- 1.3, was 72.7% of that of control subjects, increasing to 89.8% of mean weight of control subjects after refeeding (mean BMI 19.0 +/- 1.2). Mean BMI of control subjects was 21.6 +/- 2.7. Compared with the control group, patients' nitrogen was initially depleted by 24.5%, increased by 18.4%, but remained 10.6% below control values (P < 0.001). Body fat was depleted by 58.4%, increased by 89.7%, but remained 21.8% below control values (P < 0.001). Thus, despite a greater initial depletion and subsequently a greater net gain, body fat remained relatively more depleted after treatment than did nitrogen and protein. Anorexia nervosa patients were shown to readily replenish protein during nutritional rehabilitation.

The role of adrenal steroid hormones in hypertension has, until recently, focused on disorders of secretion. We describe a new form of mineralocorticoid hypertension which arises from impaired metabolism of physiological glucocorticoid. 11 beta-hydroxysteroid dehydrogenase (11 beta-HSD) is responsible for the inactivation of cortisol to cortisone. Congenital absence of this enzyme (the syndrome of apparent mineralocorticoid excess) results in cortisol acting as a potent mineralocorticoid. Furthermore, inhibition of this enzyme by glycyrrhizic and glycyrrhetinic acids also accounts for the mineralocorticoid excess states seen following licorice and carbenoxolone ingestion. Whilst impaired 11 beta-HSD activity has been shown in patients with "essential" hypertension, the significance of this finding remains unknown. These clinical studies, however, have uncovered a novel physiological mechanism, whereby the mineralocorticoid receptor (which in vitro has an equal affinity for cortisol and aldosterone) is protected from cortisol excess by the action of 11 beta-HSD. Thus 11 beta-HSD plays a crucial role in determining the in vivo specificity for this receptor.

Twenty-one patients undergoing regular hemodialysis completed a trial of energy supplementation. Nine patients added the glucose polymer Polycose to their usual diet and 12 acted as control subjects. The supplemented patients were asked to incorporate 100 or 150 g polymer, equivalent to 1600 or 2400 kJ (400 or 600 kcal) into their usual diet, daily for 6 mo. This resulted in a mean increase in energy intake of 1630 kJ (p less than 0.05) and a mean weight gain of 3.1 kg (p less than 0.005). The addition of glucose polymer to the diet resulted in a mean increase in body fat of 1.8 kg and the lean body mass increased by 1.3 kg. No significant effect on plasma triglycerides, urea, or creatinine was detected. The intake of macro- and micronutrients was not adversely affected and no clinical or psychological side effects were reported. Follow-up of these patients showed that the weight gain was maintained after 6 mo. Glucose polymer was an effective energy supplement that had beneficial effects on the nutritional status of hemodialysis patients.

11 patients with polycystic ovary syndrome (hirsutism and oligomenorrhoea), but with no deficiency of 21-hydroxylase or 3 beta-hydroxysteroid dehydrogenase, had abnormal cortisol metabolism. The high ratio of 5 alpha to 5 beta cortisol metabolites in the urine is consistent with enhanced activity of 5 alpha-reductase. Urinary total cortisol metabolites were higher in patients than controls. Increased 5 alpha-reductase activity in liver and skin enhances hepatic cortisol metabolism at the expense of androgen excess and may be the underlying abnormality in polycystic ovary syndrome.

In vitro the mineralocorticoid receptor is non-specific and does not distinguish between aldosterone and cortisol. In vivo certain tissues with this receptor are aldosterone selective (eg, kidney and parotid) whereas others with the same receptor are not (eg, hippocampus and heart). Experiments in rats showed that 11 beta-hydroxysteroid dehydrogenase (which converts cortisol to cortisone in man and corticosterone to 11-dehydrocorticosterone in the rat) was much more highly concentrated in aldosterone-selective tissues than in non-selective tissues. The localisation in the selective tissues was such that the enzyme could act as a paracrine or possibly an autocrine mechanism protecting the receptor from exposure to corticosterone. Autoradiographic studies showed that protection is lost when the enzyme is inhibited; 3H-corticosterone and 3H-aldosterone were bound to similar sites. These findings seem to explain why sodium retention, hypokalaemia, and hypertension develop in subjects with congenital deficiency of 11 beta-OHSD and those in whom the enzyme has been inhibited by liquorice.

We studied biochemical measures of vitamin B-6, zinc, and copper in a group of 96 women and vitamin A and vitamin E concentrations in 89 women, all suffering from an eating disorder. Twenty-three control subjects were studied. Eating-disorder patients not taking vitamin or mineral supplements had significantly higher plasma concentrations of vitamins A and E than did control subjects (also not taking supplements). No difference was found in indices indicating vitamin B-6 status or in plasma zinc or copper concentrations. Self-induced vomiting was the only significant predictor of upper-quartile vitamin A concentrations. Upper-quartile vitamin B-6 activations (indicating lower vitamin B-6 activity) were significantly predicted only by low actual body weight. These results suggest that supplementation of micronutrient intake needs only to be considered for those eating-disorder patients at low weight and then only with water-soluble vitamins.

21 patients undergoing major abdominal surgery were randomly assigned to one of three groups. On the day of surgery and for the succeeding 4 days each group received a daily infusion of one of the following: 10 g glucose plus 70 mmol NaHCO3, 70 mmol leucine plus 70 mmol NaHCO3, or 70 mmol of sodium alpha-ketoisocaproate (KIC). No other calories were given. Leucine infusions had no significant effect on nitrogen (N) balance, 3-methylhistidine excretion, or plasma concentrations of pre-albumin or retinol-binding protein, but they increased blood acetoacetate concentration (p = 0.004). N balance was less negative (p = 0.002) and 3-methylhistidine excretion lower (p = 0.002) in the group receiving KIC than in those receiving glucose. Blood ketone bodies, plasma prealbumin, and plasma retinol-binding protein concentrations at the end of the study were significantly higher in the KIC group than in the others. These N-sparing effects of KIC may be related to the heightened ketosis that followed its administration, to suppression of protein degradation, or to an effect on liver protein turnover. KIC alone in small doses diminishes N wastage in postoperative but under the same conditions leucine does not.

In 70 paired insulin tolerance tests (ITTs) and short 'Synacthen' tests (SSTs), both of which have been advocated for assessment of the hypothalamo-pituitary-adrenal (HPA) axis, there were 51 passes on both tests, 9 failures on both, and 10 discrepant results (9 failures on the SST, 1 failure on the ITT). There was a close correlation between the maximum cortisol value achieved in the two tests. A survey of British endocrinologists showed that only 24% used the SST to assess the HPA axis. It is suggested that the SST should be used for the initial assessment of the HPA axis and the ITT reserved for patients who fail the SST, those on corticosteroid therapy, and those who have had an acute pituitary insult within 14 days.

The sodium retention associated with liquorice ingestion has been thought to be due to a direct mineralocorticoid effect, despite the fact that it does not seem to occur in patients or animals with severe adrenal insufficiency. This study in seven normal subjects given liquorice showed that sodium retention is associated with a significant change in cortisol metabolism indicating inhibition of 11-beta-hydroxysteroid dehydrogenase (11 beta-OHSD). Congenital deficiency of this enzyme produces a syndrome of apparent mineralocorticoid excess. It is suggested that in both conditions there is a defect in the renal conversion of cortisol to cortisone by 11 beta-OHSD which results in high intrarenal cortisol levels, acting on type 1 mineralocorticoid receptors to cause sodium retention.

Nutritional and trace element status as measured by plasma concentrations of magnesium, zinc, retinol (vitamin A), and alpha-tocopherol (vitamin E) and the activities of red cell enzymes dependent on thiamin and pyridoxine (vitamin B-6) were determined in 38 women suffering premenstrual syndrome and in 23 control subjects. Blood samples were collected in the premenstrual and in midfollicular phase. Diagnosis of premenstrual syndrome was based on accepted retrospective criteria and on prospective symptom reports collected over three menstrual cycles. No evidence was found to support the hypothesis that premenstrual symptoms are caused by absolute or relative nutritional deficiencies.