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Objective Adults with Prader–Willi syndrome (PWS) are at increased risk of developing age-associated diseases early in life and, like in premature aging syndromes, aging might be accelerated. We investigated leukocyte telomere length (LTL), a marker of biological age, in young adults with PWS and compared LTL to healthy young adults of similar age. As all young adults with PWS were treated with growth hormone (GH), we also compared LTL in PWS subjects to GH-treated young adults born short for gestational age (SGA). Design Cross-sectional study in age-matched young adults; 47 with PWS, 135 healthy, and 75 born SGA. Measurements LTL measured by quantitative polymerase chain reaction, expressed as telomere/single copy gene ratio. Results Median (interquartile range) LTL was 2.6 (2.4–2.8) at a median (interquartile range) age of 19.2 (17.7–21.3) years in PWS, 3.1 (2.9–3.5) in healthy young adults and 3.1 (2.8–3.4) in the SGA group. Median LTL in PWS was significantly lower compared to both control groups (P < .01). In PWS, a lower LTL tended to be associated with a lower total IQ (r = 0.35, P = .08). There was no association between LTL and duration of GH treatment, cumulative GH dose, or several risk factors for type 2 diabetes mellitus or cardiovascular disease. Conclusions Young adults with PWS have significantly shorter median LTL compared to age-matched healthy young adults and GH-treated young adults born SGA. The shorter telomeres might play a role in the premature aging in PWS, independent of GH. Longitudinal research is needed to determine the influence of LTL on aging in PWS.

Context: Recombinant human GH (rhGH) therapy in Prader-Willi syndrome (PWS) has been used by the medical community and advocated by parental support groups since its approval in the United States in 2000 and in Europe in 2001. Its use in PWS represents a unique therapeutic challenge that includes treating individuals with cognitive disability, varied therapeutic goals that are not focused exclusively on increased height, and concerns about potential life-threatening adverse events. Objective: The aim of the study was to formulate recommendations for the use of rhGH in children and adult patients with PWS. Evidence: We performed a systematic review of the clinical evidence in the pediatric population, including randomized controlled trials, comparative observational studies, and long-term studies (>3.5 y). Adult studies included randomized controlled trials of rhGH treatment for ≥6 months and uncontrolled trials. Safety data were obtained from case reports, clinical trials, and pharmaceutical registries. Methodology: Forty-three international experts and stakeholders followed clinical practice guideline development recommendations outlined by the AGREE Collaboration (www.agreetrust.org). Evidence was synthesized and graded using a comprehensive multicriteria methodology (EVIDEM) (http://bit.ly.PWGHIN). Conclusions: Following a multidisciplinary evaluation, preferably by experts, rhGH treatment should be considered for patients with genetically confirmed PWS in conjunction with dietary, environmental, and lifestyle interventions. Cognitive impairment should not be a barrier to treatment, and informed consent/assent should include benefit/risk information. Exclusion criteria should include severe obesity, uncontrolled diabetes mellitus, untreated severe obstructive sleep apnea, active cancer, or psychosis. Clinical outcome priorities should vary depending upon age and the presence of physical, mental, and social disability, and treatment should be continued for as long as demonstrated benefits outweigh the risks. Copyright

IGF-I is mainly sequestered in a 150-kDa ternary complex with IGF binding protein (IGFBP)-3 and the acid-labile subunit. Data on complex formation and factors influencing formation have not been established. Dissociation of IGF-I from the ternary complex is in part regulated by proteolysis of IGFBP-3, which reduces its affinity for IGF-I. Short small for gestational age (SGA) children have lower IGF-I and IGFBP-3 levels compared with healthy peers.The objective of the study was to determine complex formation in healthy normal-statured children and assess variables influencing complex formation. Second, we determined complex formation in short SGA children.Complex formation was assessed using (125)I-hIGF-I column chromatography in 70 controls (40 boys), median age 10.6 years, and 40 short SGA children (25 boys), median age 8.6 years. IGFBP-3 was determined by Western immunoblotting.(125)I-hIGF-I complex formation showed an age-specific pattern in healthy controls. Variables positively influencing ternary complex formation were higher serum IGF-I levels compared with IGFBP-3 levels (P.001) and lower serum IGF-II (P.001) and IGFBP-1 levels (P.001). In addition, a higher presence of proteolyzed IGFBP-3 negatively influenced 150-kDa complex formation (P = .006). At a young age, healthy children showed considerable IGFBP-3 proteolytic activity, which declined with aging (P.001). IGFBP-3 proteolytic activity was negatively correlated with IGF-I levels (P.001). Compared with healthy controls, short SGA children showed reduced IGF-I levels (-1.3 vs 0.1 SD score) and increased proteolyzed IGFBP-3 (35.1% vs 12.2%).Age-specific normative values for (125)I-hIGF-I 150-kDa ternary complex formation are presented. A decrease in IGF-I and an increase in IGF-II, IGFBP-1, and IGFBP-3 proteolytic activity associate with reduced (125)I-hIGF-I ternary complex formation. Our results suggest that in conditions in which IGF-I levels are low, such as young age and in short SGA children, IGFBP-3 proteolytic activity is increased to ensure IGF-I bioavailability.

Background: Silver-Russell syndrome (SRS; online inheritance in man 180860) is a low-birth-weight syndrome characterized by postnatal growth restriction and variable dysmorphic features. Although maternal uniparental disomy (UPD) of chromosome 7 and hypomethylation of H19 have been reported in up to 50% of all cases, no unifying mechanism is apparent. Subjects and Methods: Ten patients and their parents were studied using the Illumina GoldenGate methylation array and the Illumina 370K HumHap single-nucleotide polymorphism array to identify aberrations in DNA methylation as well as genomic changes including copy number changes and uniparental disomy events. Results: We found evidence of UPD events outside chromosome 7 in all patients. In up to 30% of patients with SRS, DNA methylation changes occur in imprinted gene loci outside 11p15.5 (PEG3, PLAGL1, and GRB10), not previously consistently linked with SRS. Furthermore, hypermethylation of GRB10 was associated with increased mRNA expression. In addition, 20% of patients appear to have DNA methylation abnormalities within multiple loci. Not all the imprinted loci with methylation defects were affected directly by UPD. Conclusions: The association of widespread UPD associated with abnormal methylation and mRNA expression in imprinted genes in SRS is consistent with the concept of UPD as an initial genomic abnormality leading to unstable DNA methylation within the regulatory network of imprinted genes. Furthermore, disruption of any one of these genes may contribute to the heterogeneous clinical spectrum of SRS.

Small for gestational age (SGA)-born children comprise a heterogeneous group in which only few genetic causes have been identified.To determine copy number variations in 18 growth-related genes in 100 SGA children with persistent short stature.Copy number variations in 18 growth-related genes (SHOX, GH1, GHR, IGF1, IGF1R, IGF2, IGFBP1-6, NSD1, GRB10, STAT5B, ALS, SOCS2, and SOCS3) were determined by an "in house" multiplex ligation-dependent probe amplification kit. The deletions were further characterized by single-nucleotide polymorphism array analysis.Two heterozygous de novo insulin-like growth factor 1 receptor (IGF1R) deletions were found: a deletion of the complete IGF1R gene (15q26.3, exons 1-21), including distally flanking sequences, and a deletion comprising exons 3-21, extending further into the telomeric region. In one case, serum IGF-I was low (-2.78 sd score), probably because of a coexisting growth hormone (GH) deficiency. Both children increased their height during GH treatment (1 mg/m(2) per day). Functional studies in skin fibroblast cultures demonstrated similar levels of IGF1R autophosphorylation and a reduced activation of protein kinase B/Akt upon a challenge with IGF-I in comparison with controls.IGF1R haploinsufficiency was present in 2 of 100 short SGA children. GH therapy resulted in moderate catch-up growth in our patients. A review of the literature shows that small birth size, short stature, small head size, relatively high IGF-I levels, developmental delay, and micrognathia are the main predictors for an IGF1R deletion.

Contains fulltext : 80813.pdf (Publisher’s version ) (Closed access) BACKGROUND: Children with Prader-Willi syndrome (PWS) have abnormal body composition and impaired growth. Short-term GH treatment has beneficial effects. OBJECTIVES: The aim of the study was to investigate effects of long-term continuous GH treatment on body composition, growth, bone maturation, and safety parameters. SETTING: We conducted a multicenter prospective trial. DESIGN: Fifty-five children with a mean +/- sd age of 5.9 +/- 3.2 yr were followed during 4 yr of continuous GH treatment (1 mg/m(2) . d). Data were annually obtained in one center: fat percentage (fat%) and lean body mass (LBM) by dual-energy x-ray absorptiometry, height, weight, head circumference, bone age, blood pressure, and fasting IGF-I, IGF binding protein-3, glucose, insulin, glycosylated hemoglobin, total cholesterol, high-density lipoprotein, and low-density lipoprotein. sd scores (SDS) were calculated according to Dutch and PWS reference values (SDS and SDS(PWS)). RESULTS: Fat%SDS was significantly lower after 4 yr of GH treatment (P < 0.0001). LBMSDS significantly increased during the first year (P = 0.02) but returned to baseline values the second year and remained unchanged thereafter. Mean +/- sd height normalized from -2.27 +/- 1.2 SDS to -0.24 +/- 1.2 SDS (P < 0.0001). Head circumference SDS increased from -0.79 +/- 1.0 at start to 0.07 +/- 1.1 SDS after 4 yr. BMISDS(PWS) significantly decreased. Mean +/- sd IGF-I and the IGF-I/IGF binding protein-3 ratio significantly increased to 2.08 +/- 1.1 and 2.32 +/- 0.9 SDS, respectively. GH treatment had no adverse effects on bone maturation, blood pressure, glucose homeostasis, and serum lipids. CONCLUSIONS: Our study in children with PWS shows that 4 yr of continuous GH treatment (1 mg/m(2) . d) improves body composition by decreasing fat%SDS and stabilizing LBMSDS and head circumference SDS and normalizes heightSDS without adverse effects. Thus, long-term continuous GH treatment is an effective and safe therapy for children with PWS.

Background: Adiponectin and resistin are fat cell-derived hormones, which are thought to be respectively protective and disadvantageous with regard to the development of cardiovascular disease and diabetes mellitus type 2. Low birth weight has been associated with increased risks for the development of these diseases. In short, small-for-gestational-age (SGA) children, GH therapy has several positive effects regarding cardiovascular risk factors. On the other hand, concern has been expressed about the effects of GH therapy on insulin sensitivity. Methods: We measured adiponectin and resistin levels in 136 short prepubertal children born SGA and their association with cardiovascular risk parameters and growth factors. Also, we compared the levels with normal-statured controls. The effect of GH treatment was evaluated in 50 short SGA children vs. baseline and vs. an untreated sex- and age-matched SGA control group. Results: Short SGA children had similar adiponectin and lower resistin levels, compared with normal-statured controls. In GH-treated SGA children, neither adiponectin nor resistin levels changed significantly during 2 yr of GH treatment. Compared with untreated sexand age-matched SGA controls, GH-treated SGA children had similar adiponectin and lower resistin levels. Adiponectin correlated inversely with age but not any cardiovascular risk parameter or growth factor. Higher IGF-I levels in GH-treated children were associated with lower resistin levels. Conclusions: Compared with normal-statured controls, short prepubertal SGA children had similar adiponectin and lower resistin levels. Two years of GH treatment had no effect on their adiponectin and resistin levels. (J Clin Endocrinol Metab 92: 117–123, 2007)

The objective of this study was to elucidate the influence of disease severity, deiodination, sulfation, thyroid hormone binding, and dopamine use on thyroid function in euthyroid sick syndrome.The study was performed at a university-affiliated pediatric intensive care unit (PICU).This was an observational cohort study.Sixty-nine children with meningococcal sepsis were studied.Differences in thyroid function among nonsurvivors, shock survivors, and sepsis survivors on PICU admission were the main outcome measures.The main study group consisted of 45 non-dopamine-treated children. All children had decreased total T3 (TT3)/rT3 ratios without elevated TSH. T4 sulfate levels were decreased in 88%. Nonsurvivors had paradoxically higher TT3/rT3 ratios than shock survivors (0.71 vs. 0.30); this ratio also correlated with shorter duration of disease (r = -0.43). TT4 and T4-binding globulin (TBG) levels declined with increasing disease severity. TBG levels correlated inversely with elastase levels (r = -0.46). Only TSH levels were significantly lower in 24 dopamine-treated children compared with non-dopamine-treated children (0.65 vs. 0.84), whereas other thyroid hormones did not significantly differ. Both higher TT3/rT3 ratios and lower TT4 levels were predictive for mortality, but this disappeared when IL-6 was entered into the regression model.All children with meningococcal sepsis showed signs of euthyroid sick syndrome. Alterations in peripheral thyroid hormone metabolism related inversely to the duration of disease and seemed to be enacted by profound induction of type 3 deiodinase rather than by down-regulation of type 1. Lower TT4 levels were related to increased turnover of TBG by elastase. Dopamine was found to suppress only TSH secretion, not other thyroid hormone levels, on PICU admission. Both the TT3/rT3 ratio and TT4 levels were predictive for mortality, but were not superior to IL-6.

Seventy-five small for gestational age (SGA) children were studied in a randomized, double-blind, dose-response GH trial with either 1 or 2 mg GH/m2·d. Mean (sd) age at the start of GH therapy was 7.3 (2.2) yr. Data were compared with Dutch reference data. In SGA boys, mean (sd) age at onset of puberty was 12.0 (1.0) and 11.6 (0.7) yr, and in SGA girls it was 10.9 (1.1) and 10.6 (1.2) yr when treated with 1 and 2 mg GH/m2·d, respectively. SGA boys treated with the lower GH dose started puberty later than the appropriate for gestational age (AGA) controls; for the other GH-dosage groups there was no significant difference in age at onset of puberty compared to AGA controls. The age at menarche and the interval between breast stage M2 and menarche were not significantly different for GH-treated SGA girls compared to their peers. The duration of puberty and pubertal height gain of GH-treated SGA boys and girls were not significantly different between the two GH-dosage groups and were comparable with untreated short children born SGA. In conclusion, long-term GH therapy in short SGA children has no influence on the age at onset and progression of puberty compared to AGA controls, regardless of treatment with a dose of 1 or 2 mg GH/m2·d. Duration of puberty and pubertal height gain were not significantly different between the GH-dosage groups.

Growth retardation is a major problem for children with chronic renal insufficiency (CRI). Recent studies have convincingly shown that recombinant human GH accelerates growth significantly, but the optimal GH dose with regard to long term growth response and safety has not yet been established. GH therapy was given to 23 prepubertal children (18 boys and 5 girls; mean +/- SD age, 7.1 +/- 3.6 yr; range, 1.6-14.1) with CRI and severe growth retardation in a double blind, dose-response trial. Patients were randomly assigned to either 2 or 4 IU GH/m2.day for 2.5 yr. During the first 6 months, there were comparable and significant increases in height velocity SD score for chronological age with both doses (P < 0.001). However, during the ensuing 2 yr, the higher GH dose induced a significantly greater improvement in height velocity SD score for chronological age than 2 IU GH. Catch-up growth was only sustained for 2.5 yr with 4 IU. In contrast, catch-up growth ceased after 6 months with 2 IU. Neither 2 nor 4 IU GH resulted in accelerated bone maturation during 2.5 yr of therapy. There was a significant increase in plasma insulin-like growth factor-I (IGF-I) levels with either dose, but significantly more so with 4 IU. Plasma IGF-II levels only increased significantly with 4 IU. The pretreatment elevation of IGF-binding protein-1 (IGFBP-1) levels decreased by 50% during the first study year with the higher GH dose, whereas there was no decrease with 2 IU. The elevated pretreatment IGFBP-3 levels increased comparably and significantly with either GH dose. Interestingly, only 4 IU resulted in a significantly greater increase in IGF-I than in IGFBP-3 levels. Regardless of GH dose, there was an insignificant decrease in fructosamine levels, whereas lipid and parathyroid concentrations remained constant. Renal function deterioration did not accelerate. GH therapy with 4 IU/m2.day induced and maintained catch-up growth during 2.5 yr in children with CRI without evidence of adverse effects. Bone maturation did not accelerate. This suggests that this higher GH dose may be beneficial for children with severe growth retardation secondary to CRI.

Growth retardation after renal transplantation (RTx) is generally attributed to prednisone (PDN) administration, although the exact mechanism is poorly understood. In a group of 19 growth-retarded post-RTx children, we studied the effect of alternate day (AD; n = 12) and daily (D; n = 7) PDN therapy (0.10-0.25 mg/kg.day) on 24-h plasma GH and cortisol profiles, once in group D and twice on successive days in group AD. The maximal plasma GH response to arginine provocation (ATT) and plasma levels of insulin-like growth factor-I (IGF-I), IGF-II, and serum IGF-binding proteins (IGFBP) were also determined. The pulsatile character of the 24-h GH secretion was sustained in all patients. However, mean GH levels were significantly lower as compared with published data for healthy children, corrected for pubertal stage and sex. The highest mean GH levels were found in boys and girls in late puberty. Group AD had similar 24-h GH profiles whether on or off PDN treatment, which did not differ significantly from the GH profiles observed in group D. The maximal GH response during ATT was greater than 10 micrograms/L in 57% of the children. Group D had significantly lower mean and maximal cortisol levels than group AD, but all patients had a normal diurnal variation. Plasma immunoreactive IGF-I and IGF-II, and serum IGFBP-1 levels were normal, but serum levels of IGFBP-3 were increased. A significant negative correlation was found between the glomerular filtration rate and serum IGFBP-3 levels. In conclusion, our findings indicate that growth-retarded renal allograft patients, receiving either alternate day or daily PDN therapy, have decreased GH secretion, but a normal diurnal rhythm of GH and cortisol secretion as well as normal plasma IGF-I and -II levels. However, growth retardation after RTx may not solely be the result of decreased GH secretion. Renal graft impairment together with decreased IGF bioavailability may, in addition to the presumed direct effects of PDN on cartilage, contribute to the growth retardation after RTx.

We studied 24-h plasma GH profiles, maximal GH responses to arginine provocation and insulin-like growth factor-I (IGF-I) and IGF-II levels in plasma in 22 euthyroid prepubertal children (mean age, 9.5 yr) with chronic renal insufficiency (glomerular filtration rate, less than 20 mL/min.1.73 m2) and severe growth retardation [mean (+/- SD) height SD score (SDS), -2.8 (1.1)]. The 24-h GH profiles were analyzed using the Pulsar program. Girls had significantly higher 24-h GH secretion than boys (P less than 0.004). Children with end-stage nephrotic syndrome had higher baseline GH levels and total area under the curve (AUCo) than patients with dysplastic kidneys (P less than 0.05), while the area under the curve above baseline (AUCb) was similar in all types of renal diseases. The type of treatment (conservative, peritoneal, hemodialysis) did not significantly influence the 24-h GH secretion. No correlation was found between 24-h GH profiles and age, height SDS for chronological age, height velocity SDS for bone age, and weight for height. Fourteen children showed a normal 24-h GH profile, defined as a GH profile with well defined, regular GH peaks returning to baseline GH levels and a distinct day and night pattern (AUCb, 90-300 micrograms/L.24 h). Four children had low profiles, with GH peaks below 10 micrograms/L, returning to baseline GH levels and occurring almost exclusively during the night (AUCb, less than 90 micrograms/L.24 h). The remaining four children had elevated 24-h GH profiles, with GH peaks on top of elevated baseline GH levels of more than 3 micrograms/L (AUCb, 35-205 micrograms/L.24 h; AUCo greater than 300 micrograms/L.24 h). In all patients 24-h urinary GH and beta 2-globulin excretion was 100-1000 times higher than that in controls. The urinary GH excretion correlated significantly with all characteristics of the 24-h GH profiles (r = 0.57-0.59; P less than 0.05). The maximal GH response during the arginine tolerance test was normal in 66% of the children. The mean (+/- SD) SDS for bone age for the IGF-I plasma levels was +1.1 (1.9), and that for IGF-II was +3.6 (3.4). IGF-I levels correlated significantly with the AUCb, maximum GH, and GH peak characteristics of the 24-h GH profiles (r = 0.05-0.73; P less than 0.02-0.001). IGF-II levels did not show any correlation with the characteristics of the endogenous GH secretion.(ABSTRACT TRUNCATED AT 400 WORDS)