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result(s) for
"de Jong, Frank H."
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Aromatase inhibitors in men: effects and therapeutic options
by
de Jong, Frank H
,
de Ronde, Willem
in
Adolescent
,
Aromatase Inhibitors - adverse effects
,
Aromatase Inhibitors - therapeutic use
2011
Aromatase inhibitors effectively delay epiphysial maturation in boys and improve testosterone levels in adult men Therefore, aromatase inhibitors may be used to increase adult height in boys with gonadotropin-independent precocious puberty, idiopathic short stature and constitutional delay of puberty. Long-term efficacy and safety of the use of aromatase inhibitors has not yet been established in males, however, and their routine use is therefore not yet recommended.
Journal Article
Osilodrostat Is a Potential Novel Steroidogenesis Inhibitor for the Treatment of Cushing Syndrome: An In Vitro Study
2019
Abstract
Context
Metyrapone and ketoconazole, frequently used steroidogenesis inhibitors for treatment of Cushing syndrome, can be associated with side effects and limited efficacy. Osilodrostat is a CYP11B1 and CYP11B2 inhibitor, with unknown effects on other steroidogenic enzymes.
Objective
To compare the effects of osilodrostat, metyrapone, and ketoconazole on adrenal steroidogenesis, and pituitary adenoma cells in vitro.
Methods
HAC15 cells, 17 primary human adrenocortical cell cultures, and pituitary adenoma cells were incubated with osilodrostat, metyrapone, or ketoconazole (0.01 to 10 µM). Cortisol and ACTH were measured using chemiluminescence immunoassays, and steroid profiles by liquid chromatography-mass spectrometry.
Results
In HAC15 cells, osilodrostat inhibited cortisol production more potently (IC50: 0.035 µM) than metyrapone (0.068 µM; P < 0.0001), and ketoconazole (0.621 µM; P < 0.0001). IC50 values of osilodrostat and metyrapone for basal cortisol production varied with a 25- and 18-fold difference, respectively, with comparable potency. Aldosterone production was inhibited more potently by osilodrostat vs metyrapone and ketoconazole. Osilodrostat and metyrapone treatment resulted in strong inhibition of corticosterone and cortisol, 11-deoxycortisol accumulation, and modest effects on adrenal androgens. No pituitary-directed effects of osilodrostat were observed.
Conclusions
Under our study conditions, osilodrostat is a potent cortisol production inhibitor in human adrenocortical cells, comparable with metyrapone. All steroidogenesis inhibitors showed large variability in sensitivity between primary adrenocortical cultures. Osilodrostat might inhibit CYP11B1 and CYP11B2, in some conditions to a lesser extent CYP17A1 activity, and a proximal step in the steroidogenesis. Osilodrostat is a promising treatment option for Cushing syndrome, and in vivo differences with metyrapone are potentially driven by pharmacokinetic differences.
The in vitro effects of osilodrostat on human adrenal steroidogenesis are studied compared with metyrapone and ketoconazole. We show that it is a promising novel treatment of Cushing syndrome.
Journal Article
Levoketoconazole, the 2S,4R Enantiomer of Ketoconazole, a New Steroidogenesis Inhibitor for Cushing’s Syndrome Treatment
by
van Koetsveld, Peter M
,
Hofland, Leo J
,
de Jong, Frank H
in
ACTH
,
Adenoma
,
Adrenocorticotropic hormone
2021
Abstract
Introduction
Racemic ketoconazole (RK) is a steroidogenesis inhibitor used for treatment of Cushing’s syndrome. Levoketoconazole (COR-003), the pure 2S,4R enantiomer, is potentially more potent and safe compared to RK. We compared in vitro effects of levoketoconazole and RK on adrenocortical and pituitary adenoma cells.
Materials and methods
HAC15 cells and 15 primary human neoplastic adrenocortical cultures (+/− ACTH), and murine (AtT20) and human corticotroph adenoma cultures were incubated with levoketoconazole or RK (0.01-10 µM). Cortisol and ACTH were measured using a chemiluminescence immunoassay system, and steroid profiles by liquid chromatography-tandem mass spectrometry (LC-MS/MS).
Results
In HAC15, levoketoconazole inhibited cortisol at lower concentrations (IC50: 0.300 µM) compared to RK (0.611 µM; P < 0.0001). IC50 values of levoketoconazole for basal cortisol production in primary adrenocortical cultures varied over a 24-fold range (0.00578-0.140 µM), with 2 patients having a higher sensitivity for levoketoconazole vs RK (2.1- and 3.7-fold). LC-MS/MS analysis in selected cases revealed more potent inhibition of cortisol and other steroid profile components by levoketoconazole vs RK. In AtT20, levoketoconazole inhibited cell growth and ACTH secretion (10 µM: −54% and −38%, respectively), and levoketoconazole inhibited cell number in 1 of 2 primary human corticotroph pituitary adenoma cultures (−44%, P < 0.001).
Conclusion
Levoketoconazole potently inhibits cortisol production in adrenocortical cells, with a variable degree of suppression between specimens. Levoketoconazole inhibits adrenal steroid production more potently compared to RK and might also inhibit ACTH secretion and growth of pituitary adenoma cells. Together with previously reported potential advantages, this indicates that levoketoconazole is a promising novel pharmacotherapy for Cushing’s syndrome.
Journal Article
Genetic Determinants of Serum Testosterone Concentrations in Men
by
Vasan, Ramachandran S.
,
Bidlingmaier, Martin
,
de Jong, Frank H.
in
Adult
,
Aged, 80 and over
,
Aging
2011
Testosterone concentrations in men are associated with cardiovascular morbidity, osteoporosis, and mortality and are affected by age, smoking, and obesity. Because of serum testosterone's high heritability, we performed a meta-analysis of genome-wide association data in 8,938 men from seven cohorts and followed up the genome-wide significant findings in one in silico (n = 871) and two de novo replication cohorts (n = 4,620) to identify genetic loci significantly associated with serum testosterone concentration in men. All these loci were also associated with low serum testosterone concentration defined as <300 ng/dl. Two single-nucleotide polymorphisms at the sex hormone-binding globulin (SHBG) locus (17p13-p12) were identified as independently associated with serum testosterone concentration (rs12150660, p = 1.2×10(-41) and rs6258, p = 2.3×10(-22)). Subjects with ≥ 3 risk alleles of these variants had 6.5-fold higher risk of having low serum testosterone than subjects with no risk allele. The rs5934505 polymorphism near FAM9B on the X chromosome was also associated with testosterone concentrations (p = 5.6×10(-16)). The rs6258 polymorphism in exon 4 of SHBG affected SHBG's affinity for binding testosterone and the measured free testosterone fraction (p<0.01). Genetic variants in the SHBG locus and on the X chromosome are associated with a substantial variation in testosterone concentrations and increased risk of low testosterone. rs6258 is the first reported SHBG polymorphism, which affects testosterone binding to SHBG and the free testosterone fraction and could therefore influence the calculation of free testosterone using law-of-mass-action equation.
Journal Article
Genetic Determinants of Circulating Estrogen Levels and Evidence of a Causal Effect of Estradiol on Bone Density in Men
by
Bhasin, Shalender
,
Uitterlinden, André G
,
Wu, Frederick C W
in
17β-Estradiol
,
Aromatase
,
Aromatase - genetics
2018
Serum estradiol (E2) and estrone (E1) levels exhibit substantial heritability.
To investigate the genetic regulation of serum E2 and E1 in men.
Genome-wide association study in 11,097 men of European origin from nine epidemiological cohorts.
Genetic determinants of serum E2 and E1 levels.
Variants in/near CYP19A1 demonstrated the strongest evidence for association with E2, resolving to three independent signals. Two additional independent signals were found on the X chromosome; FAMily with sequence similarity 9, member B (FAM9B), rs5934505 (P = 3.4 × 10-8) and Xq27.3, rs5951794 (P = 3.1 × 10-10). E1 signals were found in CYP19A1 (rs2899472, P = 5.5 × 10-23), in Tripartite motif containing 4 (TRIM4; rs17277546, P = 5.8 × 10-14), and CYP11B1/B2 (rs10093796, P = 1.2 × 10-8). E2 signals in CYP19A1 and FAM9B were associated with bone mineral density (BMD). Mendelian randomization analysis suggested a causal effect of serum E2 on BMD in men. A 1 pg/mL genetically increased E2 was associated with a 0.048 standard deviation increase in lumbar spine BMD (P = 2.8 × 10-12). In men and women combined, CYP19A1 alleles associated with higher E2 levels were associated with lower degrees of insulin resistance.
Our findings confirm that CYP19A1 is an important genetic regulator of E2 and E1 levels and strengthen the causal importance of E2 for bone health in men. We also report two independent loci on the X-chromosome for E2, and one locus each in TRIM4 and CYP11B1/B2, for E1.
Journal Article
Eight Common Genetic Variants Associated with Serum DHEAS Levels Suggest a Key Role in Ageing Mechanisms
by
Bhasin, Shalender
,
Vasan, Ramachandran S.
,
de Jong, Frank H.
in
Actin-Related Protein 2-3 Complex
,
Actin-Related Protein 2-3 Complex - genetics
,
Actin-Related Protein 2-3 Complex - metabolism
2011
Dehydroepiandrosterone sulphate (DHEAS) is the most abundant circulating steroid secreted by adrenal glands--yet its function is unknown. Its serum concentration declines significantly with increasing age, which has led to speculation that a relative DHEAS deficiency may contribute to the development of common age-related diseases or diminished longevity. We conducted a meta-analysis of genome-wide association data with 14,846 individuals and identified eight independent common SNPs associated with serum DHEAS concentrations. Genes at or near the identified loci include ZKSCAN5 (rs11761528; p = 3.15 × 10(-36)), SULT2A1 (rs2637125; p = 2.61 × 10(-19)), ARPC1A (rs740160; p = 1.56 × 10(-16)), TRIM4 (rs17277546; p = 4.50 × 10(-11)), BMF (rs7181230; p = 5.44 × 10(-11)), HHEX (rs2497306; p = 4.64 × 10(-9)), BCL2L11 (rs6738028; p = 1.72 × 10(-8)), and CYP2C9 (rs2185570; p = 2.29 × 10(-8)). These genes are associated with type 2 diabetes, lymphoma, actin filament assembly, drug and xenobiotic metabolism, and zinc finger proteins. Several SNPs were associated with changes in gene expression levels, and the related genes are connected to biological pathways linking DHEAS with ageing. This study provides much needed insight into the function of DHEAS.
Journal Article
Inhibin Alpha-Subunit (INHA) Expression in Adrenocortical Cancer Is Linked to Genetic and Epigenetic INHA Promoter Variation
by
de Herder, Wouter W.
,
Uitterlinden, Andre G.
,
de Jong, Frank H.
in
Adrenal Cortex Neoplasms - genetics
,
Adrenal Cortex Neoplasms - metabolism
,
Adrenal glands
2014
Adrenocortical carcinoma (ACC) is a rare, but highly malignant tumor of unknown origin. Inhibin α-subunit (Inha) knockout mice develop ACCs following gonadectomy. In man, INHA expression varies widely within ACC tissues and its circulating peptide inhibin pro-αC has been described as a novel tumor marker for ACC. We investigated whether genetic and epigenetic changes of the INHA gene in human ACC cause loss or variation of INHA expression. To this end, analyses of INHA sequence, promoter methylation and mRNA expression were performed in human adrenocortical tissues. Serum inhibin pro-αC levels were also measured in ACC patients. INHA genetic analysis in 37 unique ACCs revealed 10 novel, heterozygous rare variants. Of the 3 coding bases affected, one variant was synonymous and two were missense variants: S72F and S184F. The minor allele of rs11893842 at -124 bp was observed at a low frequency (24%) in ACC samples and was associated with decreased INHA mRNA levels: 4.7±1.9 arbitrary units for AA, compared to 26±11 for AG/GG genotypes (P = 0.034). The methylation of four proximal INHA promoter CpGs was aberrantly increased in five ACCs (47.7±3.9%), compared to normal adrenals (18.4±0.6%, P = 0.0052), whereas the other 14 ACCs studied showed diminished promoter methylation (9.8±1.1%, P = 0.020). CpG methylation was inversely correlated to INHA mRNA levels in ACCs (r = -0.701, p = 0.0036), but not associated with serum inhibin pro-αC levels. In conclusion, aberrant methylation and common genetic variation in the INHA promoter occur in human ACCs and are associated with decreased INHA expression.
Journal Article
A Polymorphism in the Glucocorticoid Receptor Gene, Which Decreases Sensitivity to Glucocorticoids In Vivo, Is Associated With Low Insulin and Cholesterol Levels
by
Diederick E. Grobbee
,
Cornelia M. van Duyn
,
Steven W.J. Lamberts
in
Adrenocortical hormones
,
Age groups
,
Aged
2002
A Polymorphism in the Glucocorticoid Receptor Gene, Which Decreases Sensitivity to Glucocorticoids In Vivo, Is Associated
With Low Insulin and Cholesterol Levels
Elisabeth F.C. van Rossum 1 ,
Jan W. Koper 1 ,
Nannette A.T.M. Huizenga 1 ,
André G. Uitterlinden 1 ,
Joop A.M.J.L. Janssen 1 ,
Albert O. Brinkmann 2 ,
Diederick E. Grobbee 3 ,
Frank H. de Jong 1 ,
Cornelia M. van Duyn 4 ,
Huibert A.P. Pols 1 and
Steven W.J. Lamberts 1
1 Department of Internal Medicine, Erasmus Medical Center, Rotterdam, the Netherlands
2 Department of Endocrinology & Reproduction, Erasmus Medical Center, Rotterdam, the Netherlands
3 Department of Julius Center, University of Utrecht, Utrecht, the Netherlands
4 Department of Epidemiology & Biostatistics, Erasmus Medical Center, Rotterdam, the Netherlands
Abstract
We investigated whether a polymorphism in codons 22 and 23 of the glucocorticoid (GC) receptor gene [GAGAGG(GluArg) → GAAAAG(GluLys)]
is associated with altered GC sensitivity, anthropometric parameters, cardiovascular risk factors, and sex steroid hormones.
In a subgroup of 202 healthy elderly subjects of the Rotterdam Study, we identified 18 heterozygotes (8.9%) for the 22/23EK
allele (ER22/23EK carriers). In the highest age group, the number of ER22/23EK carriers was higher (67–82 years, 12.9%) than
in the youngest age group (53–67 years, 4.9%; P < 0.05). Two dexamethasone (DEX) suppression tests with 1 and 0.25 mg DEX were performed, and serum cortisol and insulin
concentrations were compared between ER22/23EK carriers and noncarriers. After administration of 1 mg DEX, the ER22/23EK group
had higher serum cortisol concentrations (54.8 ± 18.3 vs. 26.4 ± 1.4 nmol/l, P < 0.0001), as well as a smaller decrease in cortisol (467.0 ± 31.7 vs. 484.5 ± 10.3 nmol/l, P < 0.0001). ER22/23EK carriers had lower fasting insulin concentrations ( P < 0.001), homeostasis model assessment- insulin resistance (IR) (index of IR, P < 0.05), and total ( P < 0.02) and LDL cholesterol concentrations ( P < 0.01). Our data suggest that carriers of the 22/23EK allele are relatively more resistant to the effects of GCs with respect
to the sensitivity of the adrenal feedback mechanism than noncarriers, resulting in a better metabolic health profile.
Footnotes
Address correspondence and reprint requests to J.W. Koper, Department of Internal Medicine, Room Bd 277, Erasmus Medical Center,
P.O. Box 2040, 3000 CA Rotterdam, the Netherlands. E-mail: koper{at}inw3.fgg.eur.nl .
Received for publication 10 April 2002 and accepted in revised form 2 July 2002.
CBG, cortisol-binding globulin; DEX, dexamethasone; DST, DEX suppression test; DHEAS, dehydroepiandrosterone-sulfate; GC,
glucocorticoid; GR, GC receptor; HOMA, homeostasis model assessment; HOMA-B, HOMA β-cell function; HPA, hypothalamo-pituitary-adrenal;
IGF-BP1, IGF-binding protein 1; IR, insulin resistance; RFLP, restriction fragment-length polymorphism; RIA, radioimmunoassay;
SHBG, sex hormone-binding globulin.
DIABETES
Journal Article
CYP11B1 variants influence skeletal maturation via alternative splicing
by
Oberfield, Sharon E
,
Kelly, Andrea
,
Grgic Olja
in
Adrenal glands
,
Alternative splicing
,
Biology
2021
We performed genome-wide association study meta-analysis to identify genetic determinants of skeletal age (SA) deviating in multiple growth disorders. The joint meta-analysis (N = 4557) in two multiethnic cohorts of school-aged children identified one locus, CYP11B1 (expression confined to the adrenal gland), robustly associated with SA (rs6471570-A; β = 0.14; P = 6.2 × 10−12). rs6410 (a synonymous variant in the first exon of CYP11B1 in high LD with rs6471570), was prioritized for functional follow-up being second most significant and the one closest to the first intron-exon boundary. In 208 adrenal RNA-seq samples from GTEx, C-allele of rs6410 was associated with intron 3 retention (P = 8.11 × 10−40), exon 4 inclusion (P = 4.29 × 10−34), and decreased exon 3 and 5 splicing (P = 7.85 × 10−43), replicated using RT-PCR in 15 adrenal samples. As CYP11B1 encodes 11-β-hydroxylase, involved in adrenal glucocorticoid and mineralocorticoid biosynthesis, our findings highlight the role of adrenal steroidogenesis in SA in healthy children, suggesting alternative splicing as a likely underlying mechanism.Olja Grgic, Matthew Gazzara, and Alessandra Chesi et al. perform a genome-wide association study meta-analysis for skeletal age in two pediatric cohorts. They observe that variation in the adrenal gene, CYP11B1, impacts its alternative splicing, suggesting that adrenal steroidogenesis may contribute toward variation in skeletal age in otherwise healthy children.
Journal Article
A Genome-Wide Association Meta-Analysis of Circulating Sex Hormone–Binding Globulin Reveals Multiple Loci Implicated in Sex Steroid Hormone Regulation
by
Bidlingmaier, Martin
,
de Jong, Frank H.
,
Liu, Simin
in
Alleles
,
Chronic illnesses
,
Clinical Medicine
2012
Sex hormone-binding globulin (SHBG) is a glycoprotein responsible for the transport and biologic availability of sex steroid hormones, primarily testosterone and estradiol. SHBG has been associated with chronic diseases including type 2 diabetes (T2D) and with hormone-sensitive cancers such as breast and prostate cancer. We performed a genome-wide association study (GWAS) meta-analysis of 21,791 individuals from 10 epidemiologic studies and validated these findings in 7,046 individuals in an additional six studies. We identified twelve genomic regions (SNPs) associated with circulating SHBG concentrations. Loci near the identified SNPs included SHBG (rs12150660, 17p13.1, p = 1.8 × 10(-106)), PRMT6 (rs17496332, 1p13.3, p = 1.4 × 10(-11)), GCKR (rs780093, 2p23.3, p = 2.2 × 10(-16)), ZBTB10 (rs440837, 8q21.13, p = 3.4 × 10(-09)), JMJD1C (rs7910927, 10q21.3, p = 6.1 × 10(-35)), SLCO1B1 (rs4149056, 12p12.1, p = 1.9 × 10(-08)), NR2F2 (rs8023580, 15q26.2, p = 8.3 × 10(-12)), ZNF652 (rs2411984, 17q21.32, p = 3.5 × 10(-14)), TDGF3 (rs1573036, Xq22.3, p = 4.1 × 10(-14)), LHCGR (rs10454142, 2p16.3, p = 1.3 × 10(-07)), BAIAP2L1 (rs3779195, 7q21.3, p = 2.7 × 10(-08)), and UGT2B15 (rs293428, 4q13.2, p = 5.5 × 10(-06)). These genes encompass multiple biologic pathways, including hepatic function, lipid metabolism, carbohydrate metabolism and T2D, androgen and estrogen receptor function, epigenetic effects, and the biology of sex steroid hormone-responsive cancers including breast and prostate cancer. We found evidence of sex-differentiated genetic influences on SHBG. In a sex-specific GWAS, the loci 4q13.2-UGT2B15 was significant in men only (men p = 2.5 × 10(-08), women p = 0.66, heterogeneity p = 0.003). Additionally, three loci showed strong sex-differentiated effects: 17p13.1-SHBG and Xq22.3-TDGF3 were stronger in men, whereas 8q21.12-ZBTB10 was stronger in women. Conditional analyses identified additional signals at the SHBG gene that together almost double the proportion of variance explained at the locus. Using an independent study of 1,129 individuals, all SNPs identified in the overall or sex-differentiated or conditional analyses explained ~15.6% and ~8.4% of the genetic variation of SHBG concentrations in men and women, respectively. The evidence for sex-differentiated effects and allelic heterogeneity highlight the importance of considering these features when estimating complex trait variance.
Journal Article