Lack of Association of the 11beta-hydroxysteroid dehydrogenase type 1 gene 83,557insA and hexose-6-phosphate dehydrogenase gene R453Q polymorphisms with body composition, adrenal androgen production, blood pressure, glucose metabolism, and dementia.

CONTEXT: Recently, it was proposed that a combination of the 83,557insA polymorphism in the 11beta-hydroxysteroid dehydrogenase type 1 (HSD11B1) gene and the R453Q polymorphism in the hexose-6-phosphate dehydrogenase (H6PD) gene interacts to cause cortisone reductase deficiency (CRD) when at least three alleles are affected. OBJECTIVE: The aim was to study the separate and combined effects of these polymorphisms on body composition, adrenal androgen production, blood pressure, glucose metabolism, and the incidence of dementia in the healthy elderly population. DESIGN/SETTING/PARTICIPANTS: The Rotterdam study (n = 6105) and the Frail Old Men study (n = 347) are population-based cohort studies in the elderly. MAIN OUTCOME MEASURES: Genotype distributions and influences of (combined) genotypes on body mass index, adrenal androgen production, waist to hip ratio, systolic and diastolic blood pressure, fasting glucose levels, glucose tolerance test, and incidence of dementia were measured. RESULTS: No influence of the HSD11B1 83,557insA (allele frequencies 22.0 and 21.5%) and H6PD R453Q (allele frequencies 22.9 and 20.2%) variants was found for the different outcome measures that were investigated, either separately or when at least three alleles were affected. CONCLUSIONS: Two population-based studies among Caucasian elderly showed no evidence for (combined) effects of two polymorphisms in the HSD11B1 and H6PD genes on body composition, adrenal androgen production, blood pressure, glucose metabolism, and incidence of dementia. Moreover, the high frequencies observed for these two polymorphisms do not correspond to the low incidence of CRD observed in the general population. Altogether, it is unlikely that these polymorphisms cause CRD.

Strategies for the characterization of disorders in cortisol sensitivity.

CONTEXT: The clinical presentation of abnormalities in glucocorticoid (GC) sensitivity is diverse, and therefore it is difficult to diagnose this condition. OBJECTIVE AND DESIGN: The objective of the study was to develop strategies for the characterization of GC sensitivity disorders. SETTING: The study was conducted in an outpatient clinic. PATIENTS: Nine patients with GC sensitivity disorders participated. INTERVENTIONS: Sequence analysis of the GC receptor (GR), determination of GR number per cell, GR ligand-binding affinity, and GR splice regulation were performed in freshly prepared peripheral blood mononuclear lymphocytes and Epstein-Barr virus-transformed lymphoblasts. Cellular GC sensitivity was determined ex vivo by measuring the effect of dexamethasone on GC-induced leucine-zipper and IL-2 mRNA levels and on cell proliferation. RESULTS: Differences in GR number per cell, GR affinity, GR splice variants, and effects on transactivation or transrepression of GC-sensitive genes were observed between patients and controls. Epstein-Barr virus transformation of lymphoblasts had no influence on GR affinity but increased the GR number 5-fold in healthy controls. In patients diagnosed as cortisol resistant, however, GR number after transformation was increased significantly less than 5-fold, whereas a higher GR number was observed in a patient suspected of cortisol hypersensitivity. CONCLUSION: This study illustrates several strategies to define abnormalities in GC sensitivity by describing nine patients with affected GC sensitivity, all with a unique clinical course and background.

Two polymorphisms in the glucocorticoid receptor gene directly affect glucocorticoid-regulated gene expression.

CONTEXT: Interindividual variation in glucocorticoid (GC)-sensitivity can be partly explained by polymorphisms in the GC receptor (GR) gene. The ER22/23EK and N363S polymorphisms have been described to be associated with lower and higher GC sensitivity, respectively. OBJECTIVE AND DESIGN: We examined the basis of this altered GC sensitivity by expressing GR(N363S) and GR(ER22/23EK) in COS-1 cells and investigating their transactivating and transrepressing capacities using a GC response element-luciferase reporter and a p65-activated nuclear factor kappaB-luciferase reporter, respectively. Furthermore, we evaluated the transactivating and transrepressing capacities of the GR in peripheral blood mononuclear lymphocytes of homozygous and heterozygous carriers of these polymorphisms by determining the maximum effect of dexamethasone on transactivation of the GC-induced leucine-zipper and transinhibition of the IL-2 gene by means of real-time RT-PCR. RESULTS: The effects of the polymorphisms in the GR gene previously observed in population studies were also detected at the level of gene expression. The ER22/23EK polymorphism resulted in a significant reduction of transactivating capacity, in both transfection experiments (-14 +/- 5%, P < 0.05) and peripheral blood mononuclear lymphocytes of carriers of this polymorphism (homozygous: -48 +/- 6%, P < 0.01, n = 1; heterozygous: -21 +/- 4%, P = 0.08, n = 3). The N363S polymorphism, associated with increased GC sensitivity, resulted in a significantly increased transactivating capacity, both in vitro (8 +/- 3%; P < 0.02) and ex vivo (homozygous: 204 +/- 19%, P < 0.0001, n = 1; heterozygous: 124 +/- 8%, P = 0.05, n = 3). Neither the ER22/23EK nor the N363S polymorphism seemed to influence the transrepressing capacity of the GR. CONCLUSION: The presence of these and other GC sensitivity-modulating polymorphisms may have consequences for the use of GCs in a clinical setting.

A common polymorphism in the CYP3A7 gene is associated with a nearly 50% reduction in serum dehydroepiandrosterone sulfate levels.

CONTEXT: CYP3A7, expressed in the human fetal liver and normally silenced after birth, plays a major role in the 16alpha-hydroxylation of dehydroepiandrosterone (DHEA), DHEA sulfate (DHEAS), and estrone. Due to a replacement of part of the CYP3A7 promoter with a sequence identical with the same region in the CYP3A4 promoter (referred to as CYP3A7*1C), some individuals still express a variant of the CYP3A7 gene later in life. OBJECTIVE: The objective of this study was to examine the effect of the CYP3A7*1C polymorphism on serum steroid hormone levels. DESIGN, SETTING, PARTICIPANTS: Two population-based cohort studies were performed. Study group 1 consisted of 208 subjects randomly selected from the Rotterdam Study, and study group 2 consisted of 345 elderly independently living men. MAIN OUTCOME MEASURES: Serum DHEA(S), androstenedione, estradiol, estrone, and testosterone levels were the main outcome measures. RESULTS: In study groups 1 and 2, heterozygous CYP3A7*1C carriers had almost 50% lower DHEAS levels compared with homozygous carriers of the reference allele [study group 1, 1.74 +/- 0.25 vs. 3.33 +/- 0.15 micromol/liter (P = 0.02); study group 2, 2.09 +/- 0.08 vs. 1.08 +/- 0.12 micromol/liter (P < 0.001)]. No differences in circulating DHEA, androstenedione, estradiol, or testosterone levels were found. However, in study group 2, serum estrone levels were lower in heterozygous CYP3A7*1C carriers compared with homozygous carriers of the reference allele (0.11 +/- 0.002 vs. 0.08 +/- 0.006 nmol/liter; P < 0.001). CONCLUSION: The CYP3A7*1C polymorphism causes the persistence of enzymatic activity of CYP3A7 during adult life, resulting in lower circulating DHEAS and estrone levels.

Differential regulation of synthetic glucocorticoids on gene expression levels of glucocorticoid-induced leucine zipper and interleukin-2.

Individual glucocorticoid (GC) sensitivity was determined by measuring the effects of several clinically used GCs on transactivation of the GC-induced leucine zipper (GILZ) gene and on transrepression of the IL-2 gene using quantitative real-time PCR. A clear difference in relative potencies for transactivation and transrepression of the various GCs was observed, suggesting differential effects. To determine whether the in vitro outcomes could predict in vivo effects of GCs, 15 individuals underwent a 0.25-mg dexamethasone (DEX) suppression test (DST) while determining GILZ and IL-2 mRNA levels in their peripheral blood mononuclear cells incubated with hydrocortisone, DEX, budesonide, and prednisolone. No correlations were found between the DST and the two expression assays. However, significant correlations existed between hydrocortisone and DEX (r = 0.52; P = 0.046), hydrocortisone and budesonide (r = 0.48; P = 0.069), and hydrocortisone and prednisolone (r = 0.86; P = 0.007) regarding GILZ mRNA levels, and between hydrocortisone and DEX (r = 0.62; P = 0.014), hydrocortisone and budesonide (r = 0.71; P = 0.003), and hydrocortisone and prednisolone (r = 0.71; P = 0.047) regarding IL-2 mRNA levels. In conclusion, intra- and inter-individual variations in GC sensitivity were observed using two expression assays representing GC-mediated transactivation and transrepression. The two expression assays did not correlate with each other or with the results of the DST. This suggests that regulation of the hypothalamic-pituitary-adrenal axis is more complex. However, within an individual person, these two tests combined might predict what type and dosage of GC will be preferable in individual patients for its inhibitory clinical effects, together with relatively fewer transactivating effects related to adverse effects.