Twenty-four-hour growth hormone (GH) profiles in 26 girls with Turner's syndrome were compared with those of 26 normally growing short children and 24 slowly growing short children. All children were prepubertal and below 12 years of age. A subgroup of 13 girls was treated with ethinyl estradiol and a 24-h GH profile was reassessed. In an additional group of 45 girls with Turner's syndrome (aged 6.7–18.9 years) the effect of age, spontaneous breast development and ethinyl estradiol treatment was studied. The profiles were assessed by Fourier analysis. The oscillatory activity and the mean 24-h GH concentration were similar in children with Turner's syndrome and the normally growing short children, in contrast to lower levels in the slowly growing short children. The periodicity of GH secretion was similar in all groups. In the longitudinal study, ethinyl estradiol treatment resulted in a significant increase in pulse amplitude, but not in periodicity. In the cross-sectional study there was no significant difference between the subgroups of girls with either presence or absence of breast development or ethinyl estradiol treatment. GH secretion was not significantly related to age, height in standard deviation score or height velocity. These data imply that there is no abnormality in GH secretion in girls with Turner's syndrome.
Search Results
You are looking at 1 - 10 of 11 items for
- Author: Jan M Wit x
- Refine by Access: All content x
Jan M Wit, Albert A Massarano, Gerdine A Kamp, Peter C Hindmarsh, An van Es, Charles GD Brook, Michael A Preece, and David R Matthews
Vibor Petkovic, Maria Consolata Miletta, Annemieke M Boot, Monique Losekoot, Christa E Flück, Amit V Pandey, Andrée Eblé, Jan Maarten Wit, and Primus E Mullis
Objective
Short stature caused by biologically inactive GH is clinically characterized by lack of GH action despite normal-high secretion of GH, pathologically low IGF1 concentrations and marked catch-up growth on GH replacement therapy.
Design and methods
Adopted siblings (girl and a boy) of unknown family history were referred for assessment of short stature (−4.5 and −5.6 SDS) at the age of 10 and 8.1 years respectively. They had delayed bone ages (6.8 and 4.5 years), normal GH peaks at stimulation tests, and severely reduced IGF1 concentrations (−3.5 and −4.0 SDS). Genetic analysis of the GH1 gene showed a heterozygous P59S mutation at position involved in binding to GH receptor (GHR).
Results
Isoelectric focusing analysis of secreted GH in patient serum revealed the presence of higher GH-P59S peak compared with that of wt-GH. Furthermore, computational simulation of GH-P59S binding to GHR suggested problems in correct binding of the mutant to the GHR. In vitro GHR binding studies revealed reduced binding affinity of GH-P59S for GHR (IC50, 30 ng/ml) when compared with the wt-GH (IC50, 11.8 ng/ml) while a significantly decreased ability of the mutant to activate the Jak2/Stat5 signaling pathway was observed at physiological concentrations of 25–100 ng/ml.
Conclusions
The clinical and biochemical data of our patients support the diagnosis of partial bioinactive GH syndrome. The higher amount of GH-P59S secreted in their circulation combined with its impact on the wt-GH function on GHR binding and signaling may alter GHR responsiveness to wt-GH and could ultimately explain severe short stature found in our patients.
Emregül Işık, Belma Haliloglu, Jaap van Doorn, Hüseyin Demirbilek, Sitha A Scheltinga, Monique Losekoot, and Jan M Wit
Objective
Acid-labile subunit (ALS) deficiency (ACLSD), caused by homozygous or compound heterozygous IGFALS mutations, is associated with moderate short stature, delayed puberty, low serum IGF-I and ALS and extremely low serum IGFBP-3. Its effect on birth weight, head circumference, bone mineral density (BMD), serum IGF-II and IGFBP-2 is uncertain, as well as the phenotype of heterozygous carriers of IGFALS mutations (partial ACLSD).
Design
From all available members of five Turkish families, carrying three mutations in exon 2 of IGFALS (c.1462G > A, p.Asp488Asn (families A, B, E); c.251A > G, p.Asn84Ser (families C and E) and c.1477del, p.Arg493fs (family D)), clinical, laboratory and BMD data were collected.
Methods
Auxological and biochemical findings were expressed as SDS for age and gender. Ternary complex formation in serum was investigated by size-exclusion chromatography. BMD using DXA bone densitometry was adjusted for height and age (Ha-BMD z-score).
Results
In ACLSD (n = 24), mean ± s.d. height SDS (−2.7 ± 1.2), head circumference SDS (−2.3 ± 0.5) and body mass index (BMI) (−0.6 ± 1.0 SDS) were lower than those in partial ACLSD (n = 26, P ≤ 0.01) and birth weight SDS (n = 7) tended to be lower (−2.2 ± 1.1 vs −0.6 ± 0.3 in partial ACLSD (P = 0.07)). Serum IGF-I was −3.7 ± 1.4 vs −1.0 ± 1.0, IGF-II: −5.6 ± 0.7 vs −1.3 ± 0.7, ALS: <−4.4 ± 1.2 vs −2.1 ± 0.9 and IGFBP-3: −9.0 ± 1.9 vs −1.6 ± 0.8 SDS respectively (P < 0.001). Ha-BMD z-score was similar and normal in both groups.
Conclusions
To the known phenotype of ACLSD (i.e. short stature, reduced serum levels of IGF-I and ALS, extremely low serum IGFBP-3 and disturbed ternary complex formation), we add reduced birth weight, head circumference and serum IGF-II.
Jan M Wit, Wilma Oostdijk, Monique Losekoot, Hermine A van Duyvenvoorde, Claudia A L Ruivenkamp, and Sarina G Kant
The fast technological development, particularly single nucleotide polymorphism array, array-comparative genomic hybridization, and whole exome sequencing, has led to the discovery of many novel genetic causes of growth failure. In this review we discuss a selection of these, according to a diagnostic classification centred on the epiphyseal growth plate. We successively discuss disorders in hormone signalling, paracrine factors, matrix molecules, intracellular pathways, and fundamental cellular processes, followed by chromosomal aberrations including copy number variants (CNVs) and imprinting disorders associated with short stature. Many novel causes of GH deficiency (GHD) as part of combined pituitary hormone deficiency have been uncovered. The most frequent genetic causes of isolated GHD are GH1 and GHRHR defects, but several novel causes have recently been found, such as GHSR, RNPC3, and IFT172 mutations. Besides well-defined causes of GH insensitivity (GHR, STAT5B, IGFALS, IGF1 defects), disorders of NFκB signalling, STAT3 and IGF2 have recently been discovered. Heterozygous IGF1R defects are a relatively frequent cause of prenatal and postnatal growth retardation. TRHA mutations cause a syndromic form of short stature with elevated T3/T4 ratio. Disorders of signalling of various paracrine factors (FGFs, BMPs, WNTs, PTHrP/IHH, and CNP/NPR2) or genetic defects affecting cartilage extracellular matrix usually cause disproportionate short stature. Heterozygous NPR2 or SHOX defects may be found in ∼3% of short children, and also rasopathies (e.g., Noonan syndrome) can be found in children without clear syndromic appearance. Numerous other syndromes associated with short stature are caused by genetic defects in fundamental cellular processes, chromosomal abnormalities, CNVs, and imprinting disorders.
Yingbo Lin, Hermine A van Duyvenvoorde, Hongyu Liu, Chen Yang, Dudi Warsito, Chang Yin, Sarina G Kant, Felix Haglund, Jan M Wit, and Olle Larsson
Objective
The insulin-like growth factor1 receptor (IGF1R) is important in growth and development, and inactivating IGF1R mutations cause short stature and relatively high levels of serum IGF-I. We identified an unclassified IGF1R R1353H variant in a male with extreme tall height, very low levels of serum IGF-I and delayed and prolonged growth spurt. The index case’s mother and three sons all carried the variant, but so far only the eldest son (age 18 years) presented with tall height. We hypothesized that the variant could constitute an activating mutation.
Design
The IGF1R R1353H variant was investigated in Igf1r− / − mouse embryonic fibroblasts (R-cells) by cell cycle, colony formation and transcriptome analyses.
Results
The IGF1R R1353H (R-1353) exhibited significantly increased cell proliferation, G1-S progression and colony formation in soft agar. RNA sequencing identified 195 differentially expressed genes between R-WT and R-1353 (adjusted P < 1E-100). Most genes were upregulated in R-1353, including the gene encoding the androgen receptor (AR). Gene expression profiling showed the most significant enrichment in extracellular matrix organization (P = 2.76E-7), collagen biosynthesis (P = 1.21E-5) and cell adhesion (P = 7.38E-5). Retrospective biochemical analysis of the index case revealed decreased testosterone and sex hormone-binding globulin levels, whereas LH and FSH were within normal ranges. This profile suggests an increased sensitivity to androgen, which is compatible with the enhanced expression of Ar in R-1353 cells.
Conclusions
Our findings suggest that R1353H constitutes an activating IGF1R variant. The possible deregulation of collagen turnover and increased androgen sensitivity implicates an association to tall phenotype in male carriers.
Renata C Scalco, Vivian Hwa, Horacio M Domené, Héctor G Jasper, Alicia Belgorosky, Roxana Marino, Alberto M Pereira, Carlos A Tonelli, Jan M Wit, Ron G Rosenfeld, and Alexander A L Jorge
Context and objective
GH insensitivity with immune dysfunction caused by STAT5B mutations is an autosomal recessive condition. Heterozygous mutations in other genes involved in growth regulation were previously associated with a mild height reduction. Our objective was to assess for the first time the phenotype of heterozygous STAT5B mutations.
Methods
We genotyped and performed clinical and laboratory evaluations in 52 relatives of two previously described Brazilian brothers with homozygous STAT5B c.424_427del mutation (21 heterozygous). Additionally, we obtained height data and genotype from 1104 adult control individuals from the same region in Brazil and identified five additional families harboring the same mutation (18 individuals, 11 heterozygous). Furthermore, we gathered the available height data from first-degree relatives of patients with homozygous STAT5B mutations (17 individuals from seven families). Data from heterozygous individuals and non-carriers were compared.
Results
Individuals carrying heterozygous STAT5B c.424_427del mutation were 0.6 SDS shorter than their non-carrier relatives (P=0.009). Heterozygous subjects also had significantly lower SDS for serum concentrations of IGF1 (P=0.028) and IGFBP3 (P=0.02) than their non-carrier relatives. The 17 heterozygous first-degree relatives of patients carrying homozygous STAT5B mutations had an average height SDS of −1.4±0.8 when compared with population-matched controls (P< 0.001).
Conclusions
STAT5B mutations in the heterozygous state have a significant negative impact on height (∼3.9 cm). This effect is milder than the effect seen in the homozygous state, with height usually within the normal range. Our results support the hypothesis that heterozygosity of rare pathogenic variants contributes to normal height heritability.
Christiaan L Meuwese, Anne M Euser, Bart E Ballieux, Huib A van Vliet, Martijn J J Finken, Frans J Walther, Friedo W Dekker, and Jan M Wit
Background
The long-term effects of perinatal growth and corticosteroid exposure on adrenal steroid concentrations in adults born very preterm are uncertain.
Objectives
To examine the effect of birth weight, early postnatal growth, and pre- and postnatal corticosteroid administration on serum adrenal steroids in 19-year-old subjects born very preterm.
Design and methods
Subjects born before 32 weeks of gestation in The Netherlands participating in the Project on Preterm and Small for Gestational Age Infants (POPS) were investigated at 19 years of age. Serum cortisol, DHEA sulfate (DHEAS), and androstenedione (Adione) concentrations were measured in 393 out of 676 eligible subjects, compared with controls, and associated with perinatal growth and pre- and postnatal corticosteroids administration using multiple linear regression analyses.
Results
Serum DHEAS and Adione in men and women were higher than in controls. In the multiple regression analyses, birth weight SDS showed a statistically significant negative association with serum DHEAS concentrations in women (β: −0.865, 95% confidence interval (CI): −1.254 to −0.476) and in men (β: −0.758, 95% CI: −1.247 to −0.268) and with serum Adione concentrations in women (β: −0.337, 95% CI: −0.593 to −0.082). Early postnatal weight gain showed no association with any of measured adrenal markers. In women, serum Adione was associated with postnatal dexamethasone exposure (β: 0.932, 95% CI: 0.022 – 1.843).
Conclusions
Young adults born very preterm show elevated adrenal androgens, particularly when born small for gestational age. Postnatal corticosteroid administration is positively associated with serum Adione in young women.
Marie J E Walenkamp, Solrun Vidarsdottir, Alberto M Pereira, Marcel Karperien, Jaap van Doorn, Hermine A van Duyvenvoorde, Martijn H Breuning, Ferdinand Roelfsema, M Femke Kruithof, Jaap van Dissel, Riny Janssen, Jan M Wit, and Johannes A Romijn
Objective: STAT5b is a component of the GH signaling pathway. Recently, we described a 31-year-old male patient (height, −5.9 SDS) with a novel homozygous inactivating mutation in the STAT5b gene. The purpose of this study is to describe the phenotype in detail, including GH secretion and immunological function. In addition, we report four family members of this patient, all heterozygous carriers of the mutation.
Design and methods: Twenty-four hour GH and prolactin secretion characteristics were assessed by blood sampling at 10-min intervals. An IGF-I generation test was performed. Monocyte function was tested by stimulation of whole blood with lipopolysaccharide (LPS) in the presence or absence of Interferon-γ (IFN-γ). In addition, T cell function was determined by measuring proliferative responses of peripheral blood mononuclear cells (PBMC) after stimulation by various polyclonal activators and Interleukin-2 (IL-2). Clinical and biochemical characteristics were determined in the carriers of the mutation.
Results: GH secretory parameters were comparable with that of healthy male controls (mean fat percentage 25), but likely increased in relation to the patient’s 40% body fat. The regularity of GH secretion was diminished. Prolactin secretion was increased by sixfold. The IGF-I generation test showed a small increase in IGF-I and IGF-binding protein-3 on lower GH doses and an increase in IGF-I to −2.4 SDS on the highest dose of GH. In vitro, IL-12p40, IL 10, and tumour necrosis factor-α (TNF-α) production rates by PBMC increased to values within the normal range upon stimulation of LPS. Heterozygous carriers of the mutation did not show abnormalities, although the height of the males was below the normal range.
Conclusions: This report shows that GH and prolactin secretion were increased in this patient homozygous for a new STAT5b mutation. Although STAT5b plays a role in signaling within immune cells, clinical immunodeficiency is not an obligatory phenomenon of STAT5b deficiency per se. Heterozygous carriers of a STAT5b mutation show no signs of GH insensitivity.
Kim Freriks, Theo C J Sas, Maaike A F Traas, Romana T Netea-Maier, Martin den Heijer, Ad R M M Hermus, Jan M Wit, Janiëlle A E M van Alfen-van der Velden, Barto J Otten, Sabine M P F de Muinck Keizer-Schrama, Martin Gotthardt, Philippe H Dejonckere, Gladys R J Zandwijken, Leonie A Menke, and Henri J L M Timmers
Objective
Short stature is a prominent feature of Turner syndrome (TS), which is partially overcome by GH treatment. We have previously reported the results of a trial on the effect of oxandrolone (Ox) in girls with TS. Ox in a dose of 0.03 mg/kg per day (Ox 0.03) significantly increased adult height gain, whereas Ox mg/kg per day (0.06) did not, at the cost of deceleration of breast development and mild virilization. The aim of this follow-up study in adult participants of the pediatric trial was to investigate the long-term effects of previous Ox treatment.
Design and methods
During the previous randomized controlled trial, 133 girls were treated with GH combined with placebo (Pl), Ox 0.03, or Ox 0.06 from 8 years of age and estrogen from 12 years. Sixty-eight women (Pl, n=23; Ox 0.03, n=27; and Ox 0.06, n=18) participated in the double-blind follow-up study (mean age, 24.0 years; mean time since stopping GH, 8.7 years; and mean time of Ox/Pl use, 4.9 years). We assessed height, body proportions, breast size, virilization, and body composition.
Results
Height gain (final minus predicted adult height) was maintained at follow-up (Ox 0.03 10.2±4.9 cm, Ox 0.06 9.7±4.4 cm vs Pl 8.0±4.6 cm). Breast size, Tanner breast stage, and body composition were not different between groups. Ox-treated women reported more subjective virilization and had a lower voice frequency.
Conclusion
Ox 0.03 mg/kg per day has a beneficial effect on adult height gain in TS patients. Despite previously reported deceleration of breast development during Ox 0.03 treatment, adult breast size is not affected. Mild virilization persists in only a small minority of patients. The long-term evaluation indicates that Ox 0.03 treatment is effective and safe.
Veronica Mericq, Isabel Huang-Doran, Dhekra Al-Naqeb, Javiera Basaure, Claudia Castiglioni, Christiaan de Bruin, Yvonne Hendriks, Enrico Bertini, Fowzan S Alkuraya, Monique Losekoot, Khalid Al-Rubeaan, Robert K Semple, and Jan M Wit
Objective
To describe clinical, laboratory, and genetic characteristics of three unrelated cases from Chile, Portugal, and Saudi Arabia with severe insulin resistance, SOFT syndrome, and biallelic pathogenic POC1A variants.
Design
Observational study.
Methods
Probands’ phenotypes, including short stature, dysmorphism, and insulin resistance, were compared with previous reports.
Results
Cases 1 (female) and 3 (male) were homozygous for known pathogenic POC1A variants: c.649C>T, p.(Arg217Trp) and c.241C>T, p.(Arg81*), respectively. Case 2 (male) was compound heterozygous for p.(Arg217Trp) variant and the rare missense variant c.370G>A, p.(Asp124Asn). All three cases exhibited severe insulin resistance, acanthosis nigricans, elevated serum triglycerides and decreased HDL, and fatty liver, resembling three previously reported cases. All three also reported severe muscle cramps. Aggregate analysis of the six known cases with biallelic POC1A variants and insulin resistance showed decreased birth weight and length mean (s.d.): −2.8 (0.9) and −3.7 (0.9) SDS, respectively), severe short stature mean (s.d.) height: −4.9 (1.7) SDS) and moderate microcephaly (mean occipitofrontal circumference −3.0 (range: −4.7 to −1.2)). These findings were similar to those reported for patients with SOFT syndrome without insulin resistance. Muscle biopsy in Case 3 showed features of muscle involvement secondary to a neuropathic process.
Conclusions
Patients with SOFT syndrome can develop severe dyslipidaemic insulin resistance, independent of the exonic position of the POC1A variant. They also can develop severe muscle cramps. After diagnosis, patients should be regularly screened for insulin resistance and muscle complaints.