The growth hormone receptor in growth

Effect of Growth Hormone and Estrogen Replacement Therapy on Bone Mineral Density in Women with Turner Syndrome: A Meta-Analysis and Systematic Review

Osteoporosis is a serious implication of Turner syndrome (TS). Common methods for the treatment of TS are growth hormone (GHT) and estrogen replacement therapy (ERT). We examined the relationship between the treatment of TS and bone mineral density (BMD) of the lumbar spine. The purpose of our study was to show the currency of BMD states among patients with TS for treatment with GHT and ERT. We searched databases for studies published from inception to April 2023. The articles were related to TS, osteoporosis, ERT, GHT, BMD and treatment patients with TS. We applied the selection criteria: lumbar spine values at L1-L4; dual-energy X-ray absorptiometry (DXA); treatment which was applied: one group of articles: ERT and two group of articles: GHT; results performed as means ± SD. In total, 79 articles were analyzed, of which 20 studies were included and 5 were considered for meta-analysis. The total number of women in the articles selected was 71. Based on the results of the meta-analysis, the effect of ERT on BMD demonstrated a significant increase in BMD (the standardized mean difference in the random model was 0.593 g/cm2, 95% CI: 0.0705 to 1.116; p = 0.026), which showed that treatment with estrogen particularly increases bone mass during treatment, which contributes to reducing the risk of fractures. The effect of GHT on BMD demonstrated a non-significant decrease in BMD in patients with TS. The results for growth hormone show that this therapy does not improve bone density. However, our review emphasizes the beneficial effect of supplementing growth hormone (GH) on the clinical presentation of TS.

Short stature related to Growth Hormone Insensitivity (GHI) in childhood

Linear growth during childhood is the result of the synergic contribution of different factors. The best growth determinant system during each period of life is represented by the growth hormone-insulin-like growth factor axis (GH-IGF), even if several other factors are involved in normal growth. Within the broad spectrum of growth disorders, an increased importance has been placed on growth hormone insensitivity (GHI). GHI was reported for the first time by Laron as a syndrome characterized by short stature due to GH receptor (GHR) mutation. To date, it is recognized that GHI represents a wide diagnostic category, including a broad spectrum of defects. The peculiar characteristic of GHI is the low IGF-1 levels associated with normal or elevated GH levels and the lack of IGF-1 response after GH administration. Recombinant IGF-1 preparations may be used in the treatment of these patients.

Genetic Polymorphisms Associated with Idiopathic Short Stature and First-Year Response to Growth Hormone Treatment

BACKGROUND/AIMS

The term idiopathic short stature (ISS) describes short stature of unknown, but likely polygenic, etiology. This study aimed to identify genetic polymorphisms associated with the ISS phenotype, and with growth response to supplemental GH.

METHODS

Using a case-control analysis we compared the prevalence of "tall" versus "short" alleles at 52 polymorphic loci (17 in growth-related candidate genes, 35 identified in prior genome-wide association studies of adult height) in 94 children with ISS followed in the Genetics and Neuroendocrinology of Short Stature International Study, versus 143 controls from the Fels Longitudinal Study.

RESULTS

Four variants were nominally associated with ISS using a genotypic model, confirmed by a simultaneous confident inference approach: compared with controls children with ISS had lower odds of "tall" alleles (odds ratio, 95% CI) for GHR (0.52, 0.29-0.96); rs2234693/ESR1 (0.50, 0.25-0.98); rs967417/BMP2 (0.39, 0.17-0.93), and rs4743034/ZNF462 (0.40, 0.18-0.89). Children with ISS also had lower odds of the "tall" allele (A) at the IGFBP3 -202 promoter polymorphism (rs2855744; 0.40, 0.20-0.80) in the simultaneous confident inference analysis. A significant association with 1st-year height SD score increase during GH treatment was observed with rs11205277, located near 4 known genes: MTMR11, SV2A, HIST2H2AA3, and SF3B4; the latter, in which heterozygous mutations occur in Nager acrofacial dysostosis, appears the most relevant gene.

CONCLUSIONS

In children with ISS we identified associations with "short" alleles at a number of height-related loci. In addition, a polymorphic variant located near SF3B4 was associated with the GH treatment response in our cohort. The findings in our small study warrant further investigation.

Seasonal expressions of growth hormone receptor, insulin-like growth factor 1 and insulin-like growth factor 1 receptor in the scented glands of the muskrats (Ondatra zibethicus)

The growth hormone (GH)/insulin-like growth factor-1 (IGF-1) system plays an important role in regulating the cellular growth and organ development. The present study investigated the seasonal expressions of growth hormone receptor (GHR), IGF-1 and insulin-like growth factor 1 receptor (IGF-1R) in the scented glands of the muskrats. Morphological changes in the scented glands of the muskrats were observed significantly between the breeding and non-breeding seasons. Immunohistochemically, the expressions of GH, GHR, IGF-1 and IGF-1R were found in glandular cells and epithelial cells of the scented glands in both seasons. The protein and mRNA expression levels of GHR, IGF-1 and IGF-1R in the scented glands during the breeding season were noticeably higher than those of the non-breeding season. In parallel, the levels of GH and IGF-1 in the sera and scented glands were remarkably higher during the breeding season. In addition, small RNA sequencing showed that the predicted targets of the significantly changed hsa-miR-5100 and mmu-miR-6937-5p might regulate the expressions of Ghr, Igf-1 or Igf-1r. These results suggested that the morphological changes in the scented glands of the muskrats during the different seasons might be related to the expression levels of GHR, IGF-1 and IGF-1R. Meanwhile, GHR/IGF-1 system might regulate the scented glandular functions via endocrine or autocrine/paracrine manners.

MANAGEMENT OF ENDOCRINE DISEASE: Personalized medicine in the treatment of acromegaly

Acromegaly is associated with high morbidity and elevated mortality when not adequately treated. Surgery is the first-line treatment for most patients as it is the only one that can lead to immediate cure. In patients who are not cured by surgery, treatment is currently based on a trial-and-error approach. First-generation somatostatin receptor ligands (fg-SRL) are initiated for most patients, although approximately 25% of patients present resistance to this drug class. Some biomarkers of treatment outcome are described in the literature, with the aim of categorizing patients into different groups to individualize their treatments using a personalized approach. In this review, we will discuss the current status of precision medicine for the treatment of acromegaly and future perspectives on the use of personalized medicine for this purpose.

Rapid method for growth hormone receptor exon 3 delete (GHRd3) SNP genotyping from archival human placental samples

Analysis of archival samples from cohorts of pregnant women may be key to discovering prognosticators of stillbirth and pregnancy/perinatal complications. Growth hormone (GH) and its receptor (GHR) are pivotal in feto-placental development and pregnancy maintenance. We report a rapid, optimized method for genotyping the GHR full-length versus exon 3-deleted isoform (GHRd3). TaqMan single nucleotide polymorphism (SNP) genotyping proved superior to standard multiplex polymerase chain reaction (PCR) in allele detection and GHR genotyping from archived samples, including those with poor genomic deoxyribonucleic acid quality/quantity such as formalin fixed, paraffin embedded, blood, and serum. Furthermore, this assay is suitable for high through put 96 or 384-well plate quantitative PCR machines with automated genotype calling software. The TaqMan genotyping assay can increase the data obtained from precious archival human samples.

Effect of HT042, herbal formula, on longitudinal bone growth in spontaneous dwarf rats

HT042 is a new herbal prescription consisting of Astragalus membranaceus, Phlomis umbrosa and Eleutherococcus senticosus, which are used in Korean medicine to stimulate growth in children. We investigated the effects of HT042 on the body weight, longitudinal bone growth, and bone length in spontaneous dwarf rats (SDR). Male and female SDRs were divided into three groups: the control group (DW, 10 mL/kg/day), the recombinant human GH group (rhGH; 500 µg/kg/day), and the HT042 (100 mg/kg/day) group. Each group received the respective treatments for 10 days. Body weight was measured on day 10 of treatment. On day 8, tetracycline (20 mg/kg) was injected intraperitoneally into all individuals to form a fluorescent band on the newly synthesized bone. On day 10, femur and tibia lengths were measured using PIXImus. Body weight, longitudinal bone growth, and bone length were not affected in the HT042 group. In contrast, the rhGH group showed significantly increased body weight, longitudinal bone growth, and bone length. In conclusion, HT042 does not act through a GH-like effect to promote longitudinal bone growth.

Growth hormone receptor polymorphism and growth hormone therapy response in children: a Bayesian meta-analysis

Recombinant human growth hormone (rhGH) therapy is used in the long-term treatment of children with growth disorders, but there is considerable treatment response variability. The exon 3-deleted growth hormone receptor polymorphism (GHR(d3)) may account for some of this variability. The authors performed a systematic review (to April 2011), including investigator-only data, to quantify the effects of the GHR(fl-d3) and GHR(d3-d3) genotypes on rhGH therapy response and used a recently established Bayesian inheritance model-free approach to meta-analyze the data. The primary outcome was the 1-year change-in-height standard-deviation score for the 2 genotypes. Eighteen data sets from 12 studies (1,527 children) were included. After several prior assumptions were tested, the most appropriate inheritance model was codominant (posterior probability = 0.93). Compared with noncarriers, carriers had median differences in 1-year change-in-height standard-deviation score of 0.09 (95% credible interval (CrI): 0.01, 0.17) for GHR(fl-d3) and of 0.14 (95% CrI: 0.02, 0.26) for GHR(d3-d3). However, the between-study standard deviation of 0.18 (95% CrI: 0.10, 0.33) was considerable. The authors tested by meta-regression for potential modifiers and found no substantial influence. They conclude that 1) the GHR(d3) polymorphism inheritance is codominant, contrasting with previous reports; 2) GHR(d3) genotypes account for modest increases in rhGH effects in children; and 3) considerable unexplained variability in responsiveness remains.

Acquired growth hormone deficiency in a girl with chronic myelogenous leukemia treated with tyrosine kinase inhibitor therapy

Chronic myelogenous leukemia (CML) is caused by the BCR-ABL1 fusion gene that encodes for a constitutively-active tyrosine kinase. Adults and children with CML are typically treated with imatinib mesylate, a BCR-ABL1 tyrosine kinase inhibitor (TKI), or a second-generation TKI. Several case reports have documented growth delay of unknown mechanism in children with CML treated with imatinib. We report a seven-year-old identical twin with CML who developed significant growth delay, as compared to her twin, during five years of TKI therapy. Detailed endocrine evaluation showed acquired growth hormone deficiency, a pathway potentially inhibited by TKIs.

Biologic therapy and its effect on skeletal development in children with chronic inflammation

Chronic inflammatory conditions in children such as juvenile idiopathic arthritis, inflammatory bowel disease, cystic fibrosis and systemic lupus erythematosus can cause reduced linear growth, final height and bone mass. There are many mechanisms leading to these skeletal alterations but inflammation itself is considered to play an important role. Biologic therapy is being used increasingly for the treatment of chronic inflammatory conditions and may also be effective in improving growth and skeletal development. The main aim of this article is to summarize the effects of inflammation on growth and skeletal development and evaluate the effects of biologic therapy on growth and skeletal development in children with chronic inflammatory conditions.

Influence of the exon 3-deleted/full-length growth hormone (GH) receptor polymorphism on the response to GH replacement therapy in adults with severe GH deficiency

CONTEXT

There is considerable individual variation in the clinical response to GH replacement therapy in GH deficient (GHD) adults. Useful predictors of treatment response are lacking.

OBJECTIVE

The aim of the study was to assess the influence of the exon 3-deleted (d3-GHR) and full-length (fl-GHR) GH receptor isoforms on the response to GH replacement therapy in adults with severe GHD.

DESIGN AND PATIENTS

A total of 124 adult GHD patients (79 men; median age, 50 yr) were studied before and after 12 months of GH therapy. GHD patients were divided into those bearing fl/fl alleles (group 1) and those bearing at least one d3-GHR allele (group 2), and the genotype was related to the effects of GH therapy on IGF-I levels and total body fat (BF).

INTERVENTION

GH dose was individually titrated to obtain normal serum IGF-I levels.

MAIN OUTCOME MEASURES

GHR genotype was determined by PCR amplification, IGF-I levels by immunoassay, and BF by a four-compartment model.

RESULTS

Seventy-two (58%) patients had fl/fl genotype and were classified as group 1, whereas 52 (42%) had at least one d3-GHR allele and were classified as group 2 (40 were heterozygous and 12 were homozygous). At baseline, there were no significant differences in the study groups. Changes in IGF-I and BF after 12 months of GH treatment did not differ significantly between the two genotype groups.

CONCLUSION

The presence of d3-GHR allele did not influence the response to GH replacement therapy in our cohort of adults with severe GHD.

Common exon 3 polymorphism of the GH receptor (GHR) gene and effect of GH therapy on growth in Korean children with idiopathic short stature (ISS)

OBJECTIVE

A human GH receptor (GHR) gene exon 3 polymorphism (d3-GHR) has been reported to be associated with responsiveness to GH therapy. We assessed the frequencies of this polymorphism in Korean control and idiopathic short stature (ISS) populations, and analysed short-term growth response to GH therapy according to GHR-exon 3 genotypes in Korean children with ISS.

DESIGN AND PATIENTS

This was a retrospective study in 158 ISS children. Auxological and endocrine parameters were measured, and the GHR-exon 3 genotype was analysed. Allelic frequencies of GHR-exon 3 genotype were compared between the ISS group and a control group. GH had been administered for 62 patients, 52 of whom remained prepubertal after the first follow-up year. Changes in height velocity (HV) and IGF-1 and IGFBP-3 concentrations following GH therapy were compared in patients with these genotypes.

RESULTS

There was no difference in GHR-exon 3 genotype frequency between ISS and control groups of Koreans. However, the fl/fl genotype was more frequent in Koreans than in Caucasians. ISS children with d3-GHR showed a significantly higher increment in HV (P = 0.002) and a marginally significant increment in IGF-1 concentration (P = 0.064) at the first year of GH therapy.

CONCLUSION

fl-GHR was more frequently detected in a Korean population than in Caucasians. The growth promotion efficacy of GH therapy differed significantly between ISS patients with and without the d3-GHR allele. These findings indicate that the GHR-exon 3 polymorphism can affect the growth promoting efficacy of short-term GH therapy in Korean children with ISS.