The molecular biology of sporadic acromegaly

GH-secreting tumors represent 15 % to 20 % of all pituitary neuroendocrine tumors (pitNETs), of which 95 % occur in a sporadic context, without an identifiable inherited cause. Recent multi-omic approaches have characterized the epigenomic, genomic, transcriptomic, proteomic and kynomic landscape of pituitary tumors. Transcriptomic analysis has allowed us to discover specific transcription factors driving the differentiation of pituitary tumors and gene expression patterns. GH-secreting, along with PRL- and TSH-secreting pitNETs are driven by POU1F1; ACTH-secreting tumors are determined by TBX19; and non-functioning tumors, which are predominantly of gonadotrope differentiation are conditioned by NR5A1. Upregulation of certain miRNAs, such as miR-107, is associated with tumor progression, while downregulation of others, like miR-15a and miR-16-1, correlates with tumor size reduction. Additionally, miRNA expression profiles are linked to treatment resistance and clinical outcomes, providing insights into potential therapeutic targets. Specific somatic mutations in GNAS, PTTG1, GIPR, HGMA2, MAST and somatic variants associated with cAMP, calcium signaling, and ATP pathways have also been associated with the development of acromegaly. This review focuses on the oncogenic mechanisms by which sporadic acromegaly can develop, covering a complex series of molecular alterations that ultimately alter the balance between proliferation and apoptosis, and dysregulated hormonal secretion.

Growth during pubertal induction in girls with Turner Syndrome: a retrospective cohort analysis

CONTEXT

Patients with Turner Syndrome often present with short stature and ovarian insufficiency. The optimal method of pubertal induction to maximize adult height (AH) is unknown.

OBJECTIVE

To identify variables related to pubertal induction that are associated with growth and AH.

DESIGN & SETTING

Retrospective cohort analysis of patients attending a specialized Turner Syndrome clinic at a quaternary children's hospital.

PATIENTS

Patients with Turner Syndrome (n=107) who attended the clinic between 2015 and 2021. Of these, 51 received estradiol for pubertal induction.

MAIN OUTCOME MEASURES

Change in height standard deviation score (ΔHeightSDS) during pubertal induction, and AH.

METHODS

Age at pubertal induction, bone age delay, midparental height (MPH), growth hormone treatment, and karyotype were assessed as predictors of AH and ΔHeightSDS. Associations between karyotype and comorbidities were also assessed.

RESULTS

AH was predicted by MPH (0.8cm/cm, P=0.0001) and bone age delay (-1.84 cm/year, P= 0.006). ΔHeightSDS was predicted by growth hormone dose (0.09 SDS/mg/m2/week; P=0.017), bone age delay (-1.37 SDS/year; P=0.003), and age at pubertal induction (0.44 SDS/year; P=0.001). There was an interaction between bone age delay and pubertal induction age (P=0.013), with the combination of younger age at pubertal induction and a less-delayed bone age associated with a lower ΔHeightSDS. Karyotype did not influence AH or ΔHeightSDS, but did affect rates of other comorbidities.

CONCLUSIONS

Decisions around timing of pubertal induction in patients with Turner Syndrome should be tailored to the individual. The current approach to estrogen supplementation needs to be refined in order to facilitate pubertal induction in a physiological manner without compromising height.

Growth hormone-releasing hormone antagonists counteract interferon-γ - induced barrier dysfunction in bovine and human endothelial cells

GHRH regulates the secretion of GH from the anterior pituitary gland. An emerging body of evidence suggests that the activities of that neuropeptide are not limited to the GH/IGF-I axis, but they expand towards the mediation of inflammatory processes. GHRHAnt were developed to oppose the activities of GHRH in malignancies, and have been associated with strong anti-inflammatory and anti-oxidative effects in a diverse variety of tissues, including the lungs. In the present study we report that GHRHAnt oppose interferon-γ - induced paracellular hyperpermeability and reactive oxygen species generation in bovine and human pulmonary endothelial cells; and suppress interferon-γ - triggered STAT3, cofilin and ERK1/2 activation. Our observations substantiate previous findings on the protective effects of GHRHAnt in endothelial inflammation and barrier break-down.

High growth hormone serum partially protects mice against Trypanosoma cruzi infection

Chagas disease (CD) is one of the most devasting parasitic diseases in the Americas, affecting 7 to 8 million people worldwide. In vitro and in vivo experiments have demonstrated that growth hormone (GH) serum levels decrease as CD progresses. Interestingly, inactivating mutations in the GH receptor in humans result in Laron syndrome (LS), a clinical entity characterized by increased serum levels of GH and decreased insulin growth factor-1 (IGF-1). The largest cohort of LS subjects lives in the southern provinces of Ecuador. Remarkably, no clinical CD cases have been reported in these individuals despite living in highly endemic areas. In the current ex vivo study, we employed serum from GHR -/- mice, also known as LS mice (a model of GH resistance with high GH and low IGF-1 levels), and serum from bovine GH (bGH) transgenic mice (high GH and IGF-1), to test the effect on T. cruzi infection. We infected mouse fibroblast L-cells with Trypanosoma cruzi (etiological CD infectious agent) and treated them with serum from each mouse type. Treatment with GHR-/- serum (LS mice) significantly decreased L-cell infection by 28% compared to 48% from control wild-type mouse serum (WT). Treatment with bGH mouse serum significantly decreased infection of cells by 41% compared to 54% from WT controls. Our results suggest that high GH and low IGF-1 in blood circulation, as typically seen in LS individuals, confers partial protection against T. cruzi infection. This study is the first to report decreased T. cruzi infection using serum collected from two modified mouse lines with altered GH action (GHR-/- and bGH).

Relationship Between the Serum FGF21 Level and Growth in Children of Short Stature

BACKGROUND

This study investigated the relationship between fibroblast growth factor 21 (FGF21) levels and growth in children with growth hormone deficiency (GHD) and idiopathic short stature (ISS), and the effects of the FGF21 level on response to growth hormone (GH) treatment.

METHODS

We included 171 pre-pubertal children with a GHD (n = 54), ISS (n = 46), and normal height (n = 71). Fasting FGF21 levels were measured at baseline and every 6 months during GH treatment. Factors associated with growth velocity (GV) after GH therapy were investigated.

RESULTS

The FGF21 level was higher in short children than in the controls without significant difference between the GHD and ISS groups. In the GHD group, the FGF21 level was inversely associated with the free fatty acid (FFA) level at baseline (r = -0.28, P = 0.039), however, was positively correlated with the FFA level at 12 months (r = 0.62, P = 0.016). The GV over 12 months of GH therapy was positively associated with the delta insulin-like growth factor 1 level (β = 0.003, P = 0.020). The baseline log-transformed FGF21 level was inversely associated with GV with marginal significance (β = -0.64, P = 0.070).

CONCLUSION

The FGF21 level was higher in children of short stature, both those with GHD and the ISS, than in children with normal growth. The pretreatment FGF21 level negatively affected the GV of children with GH-treated GHD. These results suggest the existence of a GH/FFA/FGF21 axis in children.

Exogenous growth hormone promotes an epithelial-mesenchymal hybrid phenotype in cancerous HeLa cells but not in non-cancerous HEK293 cells

In cancer, the Epithelial to Mesenchymal Transition (EMT) is the process in which epithelial cells acquire mesenchymal features that allow metastasis, and chemotherapy resistance. Growth hormone (GH) has been associated with melanoma, breast, and endometrial cancer progression through an autocrine regulation of EMT. Since exogenous and autocrine expression of GH is known to have different molecular effects, we investigated whether exogenous GH is capable of regulating the EMT of cancer cells. Furthermore, we investigated whether exogenous GH could promote EMT in non-cancerous cells. To study the effect of GH (100 ng/ml) on cancer and non-cancer cells, we used HeLa and HEK293 cell lines, respectively. We evaluated the loss of cell-cell contacts, by cell scattering assay and migration by wound-healing assay. Additionally, we evaluated the morphological changes by phalloidin-staining. Finally, we evaluated the molecular markers E-cadherin and vimentin by flow cytometry. GH enhances cell scattering and the migratory rate and promotes morphological changes such as cell area increase and actin cytoskeleton filaments formation on HeLa cell line. Moreover, we found that GH favors the expression of the mesenchymal protein vimentin, followed by an increase in E-cadherin's epithelial protein expression, characteristics of an epithelial-mesenchymal hybrid phenotype that is associated with metastasis. On HEK293cells, GH promotes morphological changes, including cell area increment and filopodia formation, but not affects scattering, migration, nor EMT markers expression. Our results suggest that exogenous GH might participate in cervical cancer progression favoring a hybrid EMT phenotype but not on non-cancerous HEK293 cells.

Art and science: impact of semioccluded vocal tract exercises and choral singing on quality of life in subjects with congenital GH deficiency

Objective

Currently, not much is known about the interactions between voice and growth hormone (GH). We have described large kindred with isolated GH deficiency (IGHD) due to a GHRH receptor mutation, resulting in severe short stature and high-pitched voice. These IGHD individuals have little interest in GH treatment, as they consider themselves "short long-lived people", rather than patients. Interestingly, they report normal general quality of life, but they rate their Voice-Related Quality of Life (V-RQOL) as low. Here, we assessed the social and auditory-perceptual impacts of artistic-intervention voice therapy with semioccluded vocal tract exercises (SOVTE) and choral singing, on their voices.

Methods

Seventeen GH-naïve adult IGHD individuals were enrolled in a single-arm interventional pre-post study with 13 weekly sessions of choir singing over 90 days. Outcome measures were V-RQOL scores, self-assessment of voice, and auditory-perceptual analysis (GRBAS scale, G: grade of the severity of dysphonia; R: roughness; B: breathiness; A: asthenia; and S: strain).

Results

Marked improvements in total (p = 0.0001), physical (p = 0.0002), and socioemotional (p = 0.0001) V-RQOL scores and in self-assessment of voice (p = 0.004) were found. The general grades of vocal deviation (p = 0.0001), roughness (p = 0.0001), breathiness (p = 0.0001) and strain (p = 0.0001) exhibited accentuated reductions.

Conclusion

Voice therapy with semioccluded vocal tract exercises and choral training improved social impact and perceptual voice assessments in IGHD subjects and markedly improved their voice-related quality of life. This is particularly important in a setting where GH replacement therapy is not widely accepted.

Growth Responses During 3 Years of Growth Hormone Treatment in Children and Adolescents With Growth Hormone Deficiency: Comparison Between Idiopathic, Organic and Isolated Growth Hormone Deficiency, and Multiple Pituitary Hormone Deficiency

BACKGROUND

The study aimed to compare the growth responses to 3 years of growth hormone (GH) treatment in children and adolescents with GH deficiency (GHD) according to idiopathic, organic, isolated (IGHD), and multiple pituitary hormone deficiency (MPHD).

METHODS

Total 163 patients aged 2-18 years (100 males and 63 females; 131 idiopathic and 32 organic GHD; 129 IGHD and 34 MPHD) were included from data obtained from the LG Growth Study. Parameters of growth responses and biochemical results were compared during the 3-year GH treatment.

RESULTS

The baseline age, bone age (BA), height (Ht) standard deviation score (SDS), weight SDS, mid-parental Ht SDS, predicted adult Ht (PAH) SDS, and insulin like growth factor-1 (IGF-1) SDS were significantly higher in the organic GHD patients than in the idiopathic GHD patients, but peak GH on the GH-stimulation test, baseline GH dose, and mean 3-year-GH dosage were higher in the idiopathic GHD patients than in the organic GHD patients. The prevalence of MPHD was higher in the organic GHD patients than in the idiopathic GHD patients. Idiopathic MPHD subgroup showed the largest increase for the ΔHt SDS and ΔPAH SDS during GH treatment, and organic MPHD subgroup had the smallest mean increase after GH treatment, depending on ΔIGF-1 SDS and ΔIGF binding protein-3 (IGFBP-3) SDS. The growth velocity and the parental-adjusted Ht gain were greater in the idiopathic GHD patients than the organic GHD patients during the 3-year GH treatment, which may have been related to the different GH dose, ΔIGF-1 SDS, and ΔIGFBP-3 SDS between two groups. Multiple linear regression analysis revealed that baseline IGF-1 SDS, BA, and MPH SDS in idiopathic group and baseline HT SDS in organic group are the most predictable parameters for favorable 3-year-GH treatment.

CONCLUSION

The 3-year-GH treatment was effective in both idiopathic and organic GHD patients regardless of the presence of MPHD or underlying causes, but their growth outcomes were not constant with each other. Close monitoring along with appropriate dosage of GH and annual growth responses, not specific at baseline, are more important in children and adolescents with GHD for long-term treatment.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01604395.

Evaluation of candidate genotype of GH gene associated with growth, production and reproduction traits in Dairy Cows

Growth hormone (GH) is a major regulator of postnatal growth and metabolism in mammals and plays a critical role in growth, production and fertility in cattle. The present study was conducted in dairy cattle to find the association of g.48769565 C>T mutation with growth, production and reproduction traits in Sahiwal and Hardhenu cattle. PCR-RFLP was performed to genotype g.48769565 C>T mutation using the MspI restriction enzyme in our resource cattle population. In Hardhenu cattle, the frequencies of C and T alleles were 0.59 and 0.41 respectively while genotypic frequencies were 0.06, 0.36 and 0.58 for CC,CT and TT respectively. The frequencies of the C and T allele were 0.24 and 0.76 respectively in Sahiwal cattle and it was observed that highest frequency was forTT genotype (0.58) and lowest for CC genotype (0.06). Chi-square analysis showed that g.48769565C>T SNP loci did not meet with the Hardy-Weinberg equilibrium (p< 0.01) in Sahiwal cattle. From the least-squares analysis, it was observed that CC genotype was significantly associated with total Milk Yield (TMY), 300 days milk yield (300D MY), lactation length (LL), Dry period (DP) and Artificial insemination (AI)/conception (p<0.05). We also observed a significant association (p<0.05) of genotype CT with 3-month calves body weight. Cows with TT genotype revealed comparatively revealed favourable service period (SP) and calving interval (CI) in both Hardhenu and Sahiwal. These observed differences in their allelic and genotypic frequencies in association with the traitsunderlying production and fertility can be utilized for genetic improvement in dairy cattle.

Somatropin therapy in italian adults with growth hormone deficiency

BACKGROUND

In adult population, Growth Hormone Deficiency (GHD) is a complex clinical condition with heterogeneity of causes and duration. Growth Hormone (GH) replacement therapy has beneficial effects entailing a chronic and expensive use. Therefore, entity, appropriateness and standardization of GHD treatment need to be accurately analysed. In Italy, the epidemiological surveillance on somatropin therapy is entrusted to the National Register of Growth Hormone Therapy (Registro Nazionale degli Assuntori dell'Ormone della Crescita-RNAOC) by the Italian Regulation, in accordance of which the RNAOC-database is collecting the notifications of somatropin prescriptions.

METHODS

Aim of this study is to analyse data on somatropin-treated adult population communicated to the RNAOC by the specialist centres of 15 Italian regions and 2 autonomous provinces.

RESULTS

From 2011 to 2019, the somatropin-treated adults were 970 with 4061 examinations (1.21 ± 0.33 visits/year). The diagnoses were: hypopituitarism (n = 579); hypophysectomy (n = 383); and congenital GHD (n = 3). Five subjects were addressed with diagnoses not included in the regulation. The starting posology of somatropin was 0.320 (± 0.212) mg/day, 0.292 (± 0.167) mg/day in male and 0.360 (± 0.258) in female patients, with 7 administrations/week in 70.31% of the prescriptions. The differences in posology by gender persisted at 10th year of the follow-up. Starting dosage was higher in patients diagnosed with adult GHD before the age of 30 (0.420 ± 0.225 mg/day), with a progressive decrease of the dosage during the follow-up.

CONCLUSIONS

This is the first report on adult GH treatment, describing numbers, diagnoses, and pharmaceutical prescriptions associated to somatropin therapy in a large cohort of Italian GHD-adults.

Digital Health Platform for Emotional and Self-Management Support of Caregivers of Children Receiving Growth Hormone Treatment

In recent years there has been growing research on the combination of evidence-based behavioral change techniques with mobile-based recommender systems. In this paper, we have focused on understanding the psychological burdens experienced by caregivers of children undergoing growth hormone treatment (GHt) and the perceived barriers to and drivers of the adoption of a digital health solution. This is a mixed-methods formative research study looking into technical acceptance aspects of using digital health for the emotional support of parents of children undergoing GHt. After one month using the ADHERA CARING platform (Adhera Health, Inc., Palo Alto, CA), individual semi-structured interviews were conducted. ADHERA CARING provides tailored emotional and self-management support to caregivers of children undergoing GHt to improve adherence to treatment through positive education, personalized motivational messages, and emotional support. A preliminary thematic analysis and categorization were carried out, based on the Behavioral Intervention Technology (BIT) model. The majority of participants were female. All caregivers positively valued having the tool, especially at the beginning of treatment. Information provided in the educational module was useful and improved self-efficacy. Motivational messages contributed to commitment and reinforced the educational content, thus promoting continuity of treatment and potentially improving treatment efficacy. Most participants (n=10, 80%) accessed all educational units and completed all the 27 quiz questions. Regarding the motivational messages, the overall average rating was 4.55 out of 5.00. ADHERA CARING has the potential to help caregivers to understand the treatment journey. Nevertheless, users have identified that some types of educational content are more valuable at specific stages of the treatment journey, which suggests that personalization of educational content is required to adapt to different stages of the patient journey.

Description of a Digital Health Platform for Emotional and Self-Management Support of Caregivers of Children Receiving Growth Hormone Treatment

In this demo, we provide an overview of the digital platform ADHERA CARING which has been used for an intervention designed for emotional and self-management support of caregivers of children receiving growth hormone treatment (GHt). ADHERA CARING provides tailored emotional and self-management support to caregivers of children undergoing GHt to improve adherence to treatment through positive education, personalized motivational messages, and emotional support. This digital intervention has already been piloted in a clinical setting as part of an ongoing feasibility clinical study (NCT04812665).

Association of growth hormone and insulin-like growth factor I genotype with body weight, dominance of body weight, and mRNA expression in Korat slow-growing chickens

Objective

Growth hormone (GH) and insulin-like growth factor I (IGF-I) play a critical role in animal growth rates. We aimed to investigate the effect of GH and IGF-I genotypes on body weight (BW), dominance, and gene expression in slow-growing chickens at different ages.

Methods

A total of 613 Korat chickens (KRs) were bred and divided into three groups by genotype – A1A1, A1A3, and A3A3 for GH and AA, AC, and CC for IGF-I. Chickens were weighed every two weeks, and liver and breast muscle tissues were collected at 10 weeks of age. Genetic parameters of KRs were estimated using ASReml software. The GH and IGF-I mRNA levels were measured by quantitative polymerase chain reaction. Significant differences between traits were analyzed using the generalized linear model.

Results

A significant effect of GH genotypes on BW was found at most ages, and the A1A1 genotype had the highest value of BW. Compared with the A3A3 genotype, the A1A1 and A1A3 genotypes showed a higher dominance effect at 0 and 2 weeks, and genotype A1A1 had the highest value of dominance at 8 weeks of age. A difference in GH mRNA levels between genotypes was detected in breast muscle at 6 weeks and in the liver tissue at 2 weeks. In the case of IGF-I gene, the AA genotype had the highest BW at the beginning of life. Significant differences in BW dominance were found at 2 weeks. However, IGF-I mRNA levels were not different among genotypes in both breast muscles and liver tissues.

Conclusion

Our results revealed that GH and IGF-I influence growth, but may not be involved in heterosis. GH can be used as a marker gene in selection programs for growth because the homozygous genotype (A1A1) had the highest BW at all ages. The IGF-I is not a useful marker gene for selection programs.

Factors influencing growth hormone therapy effect during the prepubertal period in small for gestational age children without catch-up growth

PURPOSE

Because small for gestational age (SGA) children who fail to experience catch-up growth have an increased risk of short stature in adulthood, growth hormone (GH) treatment is recommended for effective growth. In this study, we evaluated the effect of GH treatment during the prepubertal period and analyzed for correlation between GH treatment response and clinical factors in SGA children.

METHODS

A retrospective, single-center study was conducted from 2014 to 2020. A total of 34 prepubertal children of short stature up to 4 years of age and born as SGA were enrolled. We recorded clinical data including birth data, age, weight, height, bone age (BA), and insulin-like growth factor 1 (IGF-1) levels.

RESULTS

The mean gestational age and birth weight were 37.50±2.51 weeks and 2,200.00±546.79 g. At the start of GH treatment, the mean chronological age and BA were 5.54±1.73 years and 4.52±1.85 years, respectively. The height standard deviation score (SDS) (-2.47±0.45) and IGF-1 SDS (0.16±1.57) were calculated. Height velocity was 9.43±1.40 cm during the first GH treatment year and 7.63±1.16 cm during the second year (P<0.05). The treatment growth response was positively correlated with young age (P=0.047) and lower BA (P=0.049) at the start of treatment. In multiple regression analysis, IGF-1 SDS change had a significantly positive association with GH treatment response (P=0.045).

CONCLUSION

GH treatment is effective for short stature SGA children who do not experience catch-up growth. Early initiation of GH treatment improved growth outcomes. As IGF-1 SDS is positively correlated with height SDS, IGF-1 monitoring is important during GH treatment of SGA prepubertal children.

[Acromegaly and it's cardiovascular implications]

Acromegaly is a chronic and slowly progressive disease that results from the hypersecretion of growth hormone (GH) and consequently insulin-like growth factor type 1 (IGF-1), due to a GH-secreting pituitary adenoma in 95-98% of cases. There are several complications or co-morbidities associated with acromegaly, the most frequent being cardiovascular, metabolic and neoplastic. The cardiovascular complications of acromegaly go from arterial hypertension to a peculiar form of cardiomyopathy and are the result of the long-standing exposure to high GH and IGF-1 levels. The pathophysiology of these complications is complex and includes an increased tubular reabsorption of sodium and the direct effects of GH and IGF-1 on the endothelium and the cardiac tissue itself. Frequently, the cardiovascular comorbidities of acromegaly occur concomitantly with metabolic complications such as diabetes and respiratory abnormalities such as the sleep apnea syndrome. In this brief review we analyze the pathophysiology, the clinical manifestations and the management of the cardiovascular complications of acromegaly.

Inter-Laboratory Agreement of Insulin-like Growth Factor 1 Concentrations Measured Intact by Mass Spectrometry

BACKGROUND

Insulin-like growth factor-I (IGF-1) is measured mainly by immunoassay for the diagnosis and treatment of growth hormone (GH) disorders, and to detect misuse of GH in sport. Immunoassays often have insufficient inter-laboratory agreement, especially between commercial kits. Over the expected range of IGF-1 in blood (∼50-500 ng/mL), in an inter-laboratory study we previously established a measurement imprecision of 11% (%CV) for the digested protein analyzed by LC-MS. Measuring intact IGF-1 by LC-MS should be simpler. However, no inter-laboratory agreement has been published.

METHODS

Intact and trypsin-digested IGF-1 in 32 serum samples from healthy volunteers and human growth hormone administration studies were analyzed by LC-MS using different instruments in five laboratories, as well as by immunoassay in a single laboratory. Another 100 samples were analyzed for IGF-1, both intact and after trypsin-digestion, in each laboratory by LC-MS. The statistical relationship between measurements and the imprecision of each assay group was assessed.

RESULTS

An intra-laboratory variability of 2-4% CV was obtained. Inter-laboratory variability was greater at 14.5% CV. Orthogonal regression of intact versus trypsin-digestion methods (n = 646) gave a slope of 1.01 and intercept of 2.05 ng/mL.

CONCLUSIONS

LC-MS measurements of IGF-1 by intact and trypsin-digestion methods are not statistically different and each is similar to immunoassay. The two LC-MS approaches may be used interchangeably or together to eliminate concerns regarding an immunoassay IGF-1 measurement. Because intact and digested IGF-1 measurements generally agreed within 20% of each other, we propose this as a criterion of assay acceptability.

Clinical Presentation, Treatment, and Outcome of Acromegaly in the United Arab Emirates

Objectives

We sought to ascertain the clinical characteristics and control rate of acromegaly in the UAE.

Methods

We conducted a multicenter retrospective analysis of all patients presenting with acromegaly to six endocrine centers in the UAE between November 2010 and December 2018. Demographic, clinical, biochemical, and radiologic data were collected. Patients were considered controlled if normal insulin-like growth factor-1 (IGF-1) level and growth hormone < 1 mcg/L were achieved at their last visit.

Results

A total of 75 patients were included in the study (60.0% males, 33.3% native UAE nationals). The mean age at diagnosis was 37.2 (range: 12-69) years. Common clinical features at diagnosis were headache (82.4%), coarse facial features (82.4%), acral enlargement (79.7%), and sweating (31.3%). Diabetes mellitus/prediabetes and hypertension were present in 45.2% and 35.5% of patients, respectively. About 82.2% had pituitary macroadenoma on pituitary magnetic resonance imaging. At presentation, 27.0% and 3.2% of the patients had secondary hypogonadism and diabetes insipidus, respectively. Overall, 76.7% of the patients underwent surgery, 20.8% received radiotherapy, and 50.7% received medical therapy. At their last clinic visit, only 43.7% of all patients achieved disease control.

Conclusions

Our study shows a high prevalence of pituitary macroadenoma in our acromegalic population, suggesting a delayed diagnosis. Also, a significant proportion of patients remained uncontrolled. Efforts to increase physician's awareness of acromegaly and to improve disease control are underway.

Effect of Growth Hormone Therapy in Patients with Noonan Syndrome: A Retrospective Study

BACKGROUND

Noonan syndrome is an autosomal dominant condition with an incidence of 1:1000 to 1:2500. The disorder is associated with distinct dysmorphic features, cardiac anomalies, developmental delay and delayed puberty. Short stature is a recognised feature of Noonan syndrome.

OBJECTIVES

The aim of this study is to assess the effect of growth hormone treatment in patients with Noonan syndrome.

METHODS

Retrospective data was collected from patients with Noonan syndrome treated with growth hormone. The results were analysed with variables expressed as mean values and standard deviation scores.

RESULTS

Twelve Noonan syndrome patients (M: F = 10:2) treated with growth hormone were identified. The mean age of starting growth hormone was 8 years, with baseline height standard deviation score of -2.96 (range: -1.64 to -5.54). The height standard deviation score significantly improved to -2.50 (P = 0.0035) and then -2.22 (P = 0.0025), following one and two years of treatment, respectively. The average height velocity for the patients prior to starting treatment was 5.16cm/year (range: 2.4 - 8.2 cm/year), which significantly improved to 7.76cm/year (ranging from 4.1 to 12.8 cm/year) after one year of growth hormone treatment (P = 0.020) and to 6.51cm/year at the end of two years.

CONCLUSIONS

Our study has shown that growth hormone treatment significantly improves the height standard deviation score of patients with Noonan syndrome over a two-year course of growth hormone therapy without any side effects. Further research is required to analyse the long-term effect of growth hormone therapy in patients with Noonan syndrome, including the impact on final adult height.

System of Criteria for Treatment Evaluation of Acromegaly in Bulgaria

Acromegaly is a rare endocrine disorder caused by excessive and longstanding secretion of growth hormone (GH) by the pituitary somatotroph and resulting from this overproduction of insulin-like growth factor-1 hormone (IGF-1) by the liver. There are few registers and rather limited clinical data about acromegaly treatment. The analysis of acromegaly data is rarely subject to a system of criteria for evaluating acromegaly treatment. The novelty of this paper is that it presents a real- life practice case study about the implementation results of such a system in Bulgaria. The case study analysis illustrates a clinical information approach to manage thousands of records in the Bulgarian Acromegaly Database. The here reported results provide evidence about the difficulties in maintaining both GH and IGF-1 levels inside their reference values in acromegaly treatment. Ongoing research extends the evaluation results by enabling semantic interoperability between acromegaly databases based on openEHR specification.

Acromegaly is associated with vertebral deformations but not vertebral fractures: Results of a cross-sectional monocentric study

OBJECTIVES

Patients with acromegaly appear to be at increased risk of vertebral fractures despite normal bone mineral density. We investigated the prevalence of vertebral fractures in a cohort of acromegalic patients under 80 years of age.

METHODS

Monocentric cross-sectional study performed at Nantes University Hospital from 1988 to 2018. Fifty patients (18 females, 32 males) with a median age of 52.3 years (range: 27-78) were included. Radiological vertebral fractures were evaluated on conventional lumbar and thoracic spine radiographs using Genant's semiquantitative fracture assessment. We studied qualitative abnormalities of the spine using three criteria: osteophytes, disc-space narrowing and wedge-shaped vertebrae. We analysed bone mineral density and endocrine status.

RESULTS

Three patients (6%) had a vertebral fracture: one grade 1 and two grade 2 according to Genant's assessment, with two osteoporotic and one osteopenic patients. They had no unsubstituted pituitary deficiency. Considering the frank deformations (osteophyte or disc narrowing≥grade 2 or wedge-shaped), the thoracic spine was deformed in 22 patients (44%) and the lumbar spine in 21 patients (42%).

CONCLUSION

Acromegalic patients had a low prevalence of vertebral fractures but had a significant amount of vertebral deformations. We speculate that this high prevalence of frank deformations could explain the previously reported high prevalence of vertebral fractures.

Pediatric Growth Hormone Deficiency (GHD) in the Recombinant Human GH (rhGH) Era

During the phase of using hGH extracted from pituitaries (pit hGH) - 1958-1985 - fundamental experience related to the diagnosis and treatment was accumulated. However, since recombinant hGH (rhGH) had become available diagnosis and treatment of GHD were conducted world-wide in a more standardized way. Treatment with rhGH was also accompanied by documentations in large international pharmaco-epidemiological surveys, which provided new insight. Despite of this development the treatment of children and adolescents with GHD raises still issues related to the most effective and efficacious as well as safe use of rhGH. This brief review attempts to discuss a few aspects related to these topics as they have developed during the rhGH era.

Regulatory Role for Growth Hormone in Statural Growth: IGF-Dependent and IGF-Independent Effects on Growth Plate Chondrogenesis and Longitudinal Bone Growth

It was initially thought that the growth-promoting effects of GH were exclusively mediated by liver-derived Insulin-like Growth Factor-I (IGF-I). Subsequent studies demonstrated that GH promotes IGF-I synthesis and activity in other organs and in the growth plate. GH has also IGF-I-independent growth-promoting effects. In Igf1 null mice, high circulating GH levels may be responsible for normal chondrocyte proliferation. Furthermore, tibial growth is reduced more in Ghr null mice than in Igf1 null mice, while the body of mice lacking both Ghr and Igf1 is smaller than that of mice lacking Igf1 or Ghr. The increased IGF-II expression in the growth plate in Igf1 null mice suggests that the IGF-I-independent effects of GH may be mediated by IGF-II. The effects of Igf1 receptor (Igf1r) gene deletion in chondrocytes indicate that GH may promote growth directly at the growth plate even when the local effects of IGF-I and IGF-II are abrogated.

Growth Hormone Treatment for Prader-Willi Syndrome

The European Marketing Authorization for recombinant human growth hormone (rhGH) in children with Prader-Willi syndrome was the first indication for metabolic and body composition effects in children. In the US it is indicated for short stature associated with PWS. Recombinant hGH is the first treatment for the PWS population and radically changed the care of these children by facilitating access to physicians who prescribe rhGH, mainly paediatric endocrinologists, and manage the organization of multidisciplinary care. Recombinant hGH treatment improved linear growth, body composition, and socialization not only in children but also in young adults. The pathophysiology of combined hormonal deficiencies including GH is starting to be unravelled. We now have to focus on co-morbidities that are not modified by rhGH treatment, such as feeding disorders and behaviour problems, to truly change the life of patients. The transition of care from adolescents to young adults also remains a challenge.

Psychosocial Aspects of Short Stature and rhGH Treatment: Implicit Trends over 60+ Years

Between 1958 and today, advances in research and the clinical management of short stature with GH have occurred. Initially, limited supply of pituitary-derived hGH led to strict criteria for diagnosing GH deficiency and tightly controlled treatment protocols. With the advent of biosynthetic GH, the supply has increased, the number of indications for treatment has grown, and the focus of intervention changed from hormone replacement to treatment of short stature. Improved psychosocial adaptation is an underlying, albeit largely unspoken and inadequately researched, target of treatment. Complicating the ability to make a definitive statement on the effects of rhGH on psychosocial adaptation is the rigor of the psychological outcomes literature. A high risk of bias present in the majority of rhGH treatment studies on psychological outcomes substantially weakens confidence in their results. Studies that convincingly demonstrate, through rigorous research design and methodology, that the benefits of rhGH exceed the risks and burdens are needed.

Associations of Ki-67 Labeling Index with Clinical and Paraclinical Features of Growth Hormone-Secreting Pituitary Adenomas: A Single Center Report from Iran

BACKGROUND

Acromegaly is a rare disorder resulting from benign growth hormone (GH)-secreting pituitary adenomas in 90% of the cases. In recent years, many researchers have studied the Ki-67 index level of pituitary tumors and its relationship with demographics, biochemical parameters, clinical behavior, and recurrence rate.

OBJECTIVES

This study aimed to evaluate the correlation of Ki-67 index level with clinicoradiological and endocrinological parameters in confirmed GH-secreting pituitary adenomas, as well as with the surgical response and medical treatment after surgery.

METHODS

We collected the medical and pathologic records of 49 patients with GH-secreting pituitary adenoma who underwent surgeries from 2008 to 2017 in Shariati hospital affiliated to Tehran University of Medical Sciences.

RESULTS

According to MRI reports, 94% of the tumors were macroadenomas. The MRI findings also revealed the median maximal adenoma diameter of 18.5 mm. About 40% of the patients achieved remission three months after the surgery. Younger patients had a significantly higher Ki-67 index level (P = 0.036). We did not observe any significant difference in the Ki-67 index level regarding gender, tumor type, maximal tumor diameter, tumor invasiveness, tumor secretory type, and remission. Interestingly, the Ki-67 index level was negatively correlated with the insulin-like growth factor-1 (IGF-1) level at the last follow-up (P = 0.02). In logistic regression analysis, patients with higher preoperative GH serum levels had a better outcome.

CONCLUSIONS

Our results indicated a negative correlation between age and Ki-67 index level. However, there was no association between the Ki-67 index level and some tumor behaviors, as well as short- and long-term remission.

Gene Sequence and Production of Recombinant MetGH/hGH

Recombinant human growth hormones were the products of a revolution in biotechnology that took place in the San Francisco Bay area of California in the 1970's. A combination of Herb Boyer's restriction enzymes with Stanley Cohen's bacterial plasmids provided the power to select and amplify virtually any gene. The complementary personalities and talents of Herb Boyer and Robert Swanson led to formation of Genentech and with it the development of a product that overcame the limitations of scarcity and the risks of slow virus contamination inherent in extracted pituitary growth hormone. The extra amino acid in metGH was dropped and other manufacturers joined in the effort to explore indications for rhGH beyond the replacement of a missing hormone. After more than thirty years of availability and careful study, we still have much to learn about the safe and effective use of rhGH.

Understanding Treatment Burden for Children Treated for Growth Hormone Deficiency

Objective

Growth hormone deficiency (GHD) treatment for children requires growth hormone injections, typically administered daily until the child reaches adult height. Child GHD treatment burden is not well understood and no disease-specific measures exist to assess this burden. The purpose of the study was to explore GHD treatment burden for children and their parents by conducting concept elicitation interviews supporting a theoretical model of the impact of GHD treatment.

Methods

Four focus groups (in Germany) and 52 telephone interviews (in the UK and USA) were conducted with children/adolescents with GHD aged 8 to <13 years and parents of children with GHD aged ≥4 to <13 years. The purpose of the interviews was to understand the experience of GHD treatment from the child’s perspective, and for parents, the impact of their child’s treatment on themselves. Interview transcripts were analyzed thematically based on modified grounded theory principles.

Results

Interviews with 70 respondents who produced descriptions (n = 73) of patients experiences with GHD treatment (three parents spoke for two children each) were conducted. Analysis identified three major areas of GHD treatment burden for children: physical; emotional well-being; and interference. Parent burdens identified were: emotional well-being and interference. Modifiers such as treatment efficacy and duration, which may impact the degree of treatment burden severity, were identified.

Conclusions

Overall treatment burden of child GHD is considerable for children and their parents. The concept elicitation and theoretical model can be used to develop a disease-specific outcome measure, which adequately reflects the burden of GHD treatment for children and their parents.

Growth Hormone Did Not Activate Its Intracellular Signaling Molecules in Rats' Liver Hepatocytes During Early Life Period

BACKGROUND

Although growth hormone (GH) has essential roles in the growth of animals, it has no growth-promoting effect during infancy period. The molecular mechanism underlying lack of growth-promoting effect of GH during infancy period remains unclear. Important signaling pathways are mediated by GH, including Janus kinase 2 (JAK2), extracellular signal-regulated kinase 1/2 (ERK1/2), signal transducers, and activators of transcription 5, 3, and 1 (STATs 5, 3 and 1).

OBJECTIVES

This study explored the underlying molecular mechanisms driving to the lack of growth-promoting effect of GH in the early stage of life by in vivo assessment of intracellular signal response (STAT5/ 3/ 1, JAK2 and ERK1/ 2) to GH at different physiological stages.

METHODS

In this study, five age groups of rats (1-, 4-day-old, and 1-, 2-, 3-week-old) were selected. The rats were anesthetized using pentobarbital (100 mg/kg) and then received the rat GH (2mg/kg) via inferior vena cava injection. The control rats were injected with normal saline during the same period. The intracellular signal response to GH was assessed by Western blot analysis.

RESULTS

JAK2 and STAT5 were expressed in 1-day and 4-day-old newborn rats and their expression levels were comparable with the levels of the 1-, 2-, and 3-week-old rats; however, JAK2/STAT5 phosphorylation was not observed in 1-day-old and 4-day-old newborn rats after stimulation with GH in the liver. Similar to JAK2 and STAT5, we did not detect STAT3/1 activation during infancy stages although basic STAT3 and STAT1 were also expressed in hepatocytes from newborn rats. In addition we detected ERK1/2 activation in 4-day-old, 1-, 2-, and 3-week-old rats but not in 1-day-old rats.

CONCLUSIONS

JAK2, STAT5, STAT3, STAT1, and ERK1/2 were not simultaneously activated by GH in newborn rats; this finding may be one of the underlying mechanism of GH insensitivity in newborn rats.

A Novel Mutation of MAGEL2 in a Patient with Schaaf-Yang Syndrome and Hypopituitarism

INTRODUCTION

Schaaf-Yang syndrome (SYS) is caused by truncating point mutations of the paternal allele of MAGEL2, an imprinted gene located in the critical region of Prader-Willi syndrome (PWS). These patients present a phenotype with neurodevelopmental delay, hypotonia, joint contractures, and a particularly high prevalence of autism (up to 75% in affected individuals). The loss of function of MAGEL2 is suggested to contribute to endocrine hypothalamic dysfunction in individuals with PWS.

CASE PRESENTATION

The current study presented the case of a patient with SYS and a novel de novo truncating mutation of MAGEL2 and phenotypic characteristics typical of this Prader-Willi-like syndrome and also including partial hypopituitarism, hypothyroidism, growth hormone deficiency, and hyperprolactinemia.

CONCLUSIONS

The clinical and molecular similarities between SYS and PWS suggested the need for a thorough endocrinological follow-up to improve the prognosis and long-term quality of life for patients with SYS.

Insulin-like Growth Factor 1 (IGF-1) as a marker of cognitive decline in normal ageing: A review

Insulin-like Growth Factor 1 (IGF-1) and its signaling pathway play a primary role in normal growth and ageing, however serum IGF-1 is known to reduce with advancing age. Recent findings suggest IGF-1 is essential for neurogenesis in the adult brain, and this reduction of IGF-1 with ageing may contribute to age-related cognitive decline. Experimental studies have shown manipulation of the GH/GF-1 axis can slow rates of cognitive decline in animals, making IGF-1 a potential biomarker of cognition, and/or its signaling pathway a possible therapeutic target to prevent or slow age-related cognitive decline. A systematic literature review and qualitative narrative summary of current evidence for IGF-1 as a biomarker of cognitive decline in the ageing brain was undertaken. Results indicate IGF-1 concentrations do not confer additional diagnostic information for those with cognitive decline, and routine clinical measurement of IGF-1 is not currently justified. In cases of established cognitive impairment, it remains unclear whether increasing circulating or brain IGF-1 may reverse or slow down the rate of further decline. Advances in neuroimaging, genetics, neuroscience and the availability of large well characterized biobanks will facilitate research exploring the role of IGF-1 in both normal ageing and age-related cognitive decline.

Effect of Growth Hormone on Final Height in Children with Idiopathic Short Stature: A UAE, Eastern Region Experience

Objectives

The use of growth hormone (GH) in idiopathic short stature (ISS) has been a subject of debate for the past two decades. We sought to assess the effect of GH on final height (FH) in patients with ISS in our region, which has a high consanguinity rate, and compare it to the effect observed in GH deficient (GHD) patients.

Methods

We conducted a retrospective chart review from 1 January 2005 to 31 December 2013 for patients with ISS or GHD from the local United Arab Emirates population who received GH treatment and were followed-up regularly in our clinic. The change in height Z-score at 12 months and FH were assessed within each group and between the two groups.

Results

Twenty-one patients with ISS and 29 patients with GHD were studied. There was a significant change in height Z-score at 12 months and FH in both groups (p < 0.001). The improvement in the ISS group was comparable to the response seen in GHD patients at 12 months (0.5±0.3 standard deviation score (SDS), and 0.5±0.4 SDS, respectively; p = 0.540). The effect on FH was better in ISS group than the GHD group of all etiologies (1.3±0.6 SDS vs. 0.9±0.7 SDS, respectively; p = 0.050), there was no difference between the ISS and the subgroup of idiopathic GHD (1.3±0.5 SDS and 1.2±0.8 SDS, respectively).

Conclusions

In our local population, GH has a positive effect on the short-term growth and FH of children with ISS to the same extent that has been observed in children with idiopathic GH deficiency.

Compound heterozygosity for two GHR missense mutations in a patient affected by Laron Syndrome: a case report

Background

Mutations localized in the Growth Hormone Receptor (GHR) gene are often associated with the pathogenesis of Laron Syndrome, an autosomal recessive hereditary disorder characterized by severe growth retardation. Biochemically, patients present normal to high circulating GH levels, in presence of very low or undetectable IGF-I levels, which do not rise after rhGH treatment.

Case presentation

We describe the case of a 3.8 years old girl with symmetrical short stature (−3.76 SDS), low IGF-1 and IGFBP-3, in presence of normal GH levels. Parents were not relatives and there was no family history of short stature. During the second day of birth, she developed severe hypoglycaemia that required glucose infusion. She presented frontal bossing and depressed nasal bridge. IGF-1 generation test showed no response, suggesting a GH resistance evidence. In the hypothesis of Laron Syndrome, we decided to perform a molecular analysis of Growth Hormone Receptor (GHR) gene. This analysis demonstrated that the patient was compound heterozygote for two missense mutations.

Conclusions

GHR gene mutations are a well demonstrated cause of GH insensitivity. In heterozygous patients, probably the normal stature may be achieved by a compensatory mechanism of GH secretion or signalling. On the contrary, in homozygous or compound heterozygous patients these compensatory mechanisms are inadequate, and short stature may be the consequence.

GH/IGF-1 Signaling and Current Knowledge of Epigenetics; a Review and Considerations on Possible Therapeutic Options

Epigenetic mechanisms play an important role in the regulation of the Growth Hormone- Insulin-like Growth Factor 1 (GH-IGF1) axis and in processes for controlling long bone growth, and carbohydrate and lipid metabolism. Improvement of methodologies that allow for the assessment of epigenetic regulation have contributed enormously to the understanding of GH action, but many questions still remain to be clarified. The reversible nature of epigenetic factors and, particularly, their role as mediators between the genome and the environment, make them viable therapeutic target candidates. Rather than reviewing the molecular and epigenetic pathways regulated by GH action, in this review we have focused on the use of epigenetic modulators as potential drugs to improve the GH response. We first discuss recent progress in the understanding of intracellular molecular mechanisms controlling GH and IGF-I action. We then emphasize current advances in genetic and epigenetic mechanisms that control gene expression, and which support a key role for epigenetic regulation in the cascade of intracellular events that trigger GH action when coupled to its receptor. Thirdly, we focus on fetal programming and epigenetic regulation at the IGF1 locus. We then discuss epigenetic alterations in intrauterine growth retardation, and the possibility for a potential epigenetic pharmaceutical approach in short stature associated with this fetal condition. Lastly, we review an example of epigenetic therapeutics in the context of growth-related epigenetic deregulation disorders. The advance of our understanding of epigenetic changes and the impact they are having on new forms of therapy creates exciting prospects for the future.

Post-prandial decrease in plasma growth hormone levels is not related to the increase in plasma insulin levels in goats

Objective

In the present study, we examined whether the post-prandial reduction in plasma growth hormone (GH) levels is related to the increase in plasma insulin levels in ruminants.

Methods

We performed two experiments: intravenous bolus injection of insulin (0.2 IU/kg body weight) or glucose (1.0 mmol/kg body weight) was administered to increase the plasma insulin levels in male Shiba goats.

Results

In the insulin injection experiment, significant (p<0.05) increase in GH concentrations was observed, 15 to 20 min after the injection; it was accompanied with a significant (p<0.01) increase in cortisol concentrations at 45 to 90 min, when compared to the concentrations in the saline-injected controls. The glucose injection significantly (p<0.05) increased the plasma GH concentration at 20 to 45 min; this was not accompanied by significantly higher cortisol concentrations than were observed for the saline-injected control. Hypoglycemia induced by the insulin injection, which causes the excitation of the adrenal cortex, might be involved in the increase in insulin levels.

Conclusion

Based on these results, we conclude that post-prandial increases in plasma insulin or glucose levels do not induce a decrease in GH concentration after feeding in the ruminants.

Growth hormone receptor antagonism with pegvisomant in insulin resistant non-diabetic men: A phase II pilot study

Background: Growth hormone (GH) is known to affect insulin and glucose metabolism.  Blocking its effects in acromegalic patients improves diabetes and glucose metabolism. We aimed to determine the effect of pegvisomant, a GH receptor antagonist, on insulin resistance, endogenous glucose production (EGP) and lipolysis in insulin resistant non-diabetic men.  Methods: Four men between the ages of 18-62 with a BMI of 18-35kg/m 2, with insulin resistance as defined by a HOMA-IR > 2.77, were treated for four weeks with pegvisomant 20 mg daily.  Inpatient metabolic assessments were performed before and after treatment. The main outcome measurements were: change after pegvisomant therapy in insulin sensitivity as measured by hyperinsulinemic euglycemic clamp; and EGP and lipolysis assessed by stable isotope tracer techniques. Results: Insulin like growth factor-1 (IGF-1) concentrations decreased from 134.0 ± 41.5 (mean ± SD) to 72.0 ± 11.7 ng/mL (p = 0.04) after 4 weeks of therapy. Whole body insulin sensitivity index (M/I 3.2 ± 1.3 vs. 3.4 ± 2.4; P = 0.82), as well as suppression of EGP (89.7 ± 26.9 vs. 83.5 ± 21.6%; p = 0.10) and Ra glycerol (59.4 ± 22.1% vs. 61.2 ± 14.4%; p = 0.67) during the clamp were not changed significantly with pegvisomant treatment. Conclusions: Blockade of the GH receptor with pegvisomant for four weeks had no significant effect on insulin/glucose metabolism in a small phase II pilot study of non-diabetic insulin resistant participants without acromegaly.

The Safety and Efficacy of Growth Hormone Secretagogues

INTRODUCTION

Growth hormone (GH) increases lean body mass, decreases fat mass, increases exercise tolerance and maximum oxygen uptake, enhances muscle strength, and improves linear growth. Long-term studies of GH administration offer conflicting results on its safety, which has led to strict Food and Drug Administration criteria for GH use. The potential drawbacks of exogenous GH use are believed to be due in part to impaired regulatory feedback.

AIM

To review the literature on GH secretagogues (GHSs), which include GH-releasing peptides and the orally available small-molecule drug ibutamoren mesylate.

METHODS

Review of clinical studies on the safety and efficacy of GHSs in human subjects.

MAIN OUTCOME MEASURE

Report on the physiologic changes from GHS use in human subjects including its safety profile.

RESULTS

GHSs promote pulsatile release of GH that is subject to negative feedback and can prevent supra-therapeutic levels of GH and their sequelae. To date, few long-term, rigorously controlled studies have examined the efficacy and safety of GHSs, although GHSs might improve growth velocity in children, stimulate appetite, improve lean mass in wasting states and in obese individuals, decrease bone turnover, increase fat-free mass, and improve sleep. Available studies indicate that GHSs are well tolerated, with some concern for increases in blood glucose because of decreases in insulin sensitivity.

CONCLUSION

Further work is needed to better understand the long-term impact of GHSs on human anatomy and physiology and more specifically in the context of a diversity of clinical scenarios. Furthermore, the safety of these compounds with long-term use, including evaluation of cancer incidence and mortality, is needed. Sigalos JT, Pastuszak AW. The Safety and Efficacy of Growth Hormone Secretagogues. Sex Med Rev 2018;6:45-53.

Multi-locus phylogeny reveals instances of mitochondrial introgression and unrecognized diversity in Kenyan barbs (Cyprininae: Smiliogastrini)

The phylogenetics and taxonomic status of small African barbs (Cyprininae: Smiliogastrini) remains unresolved despite the recent decision to elevate the genus name Enteromius for the group. The main barrier to understanding the origin of African small barbs and evolutionary relationships within the group is the poor resolution of phylogenies published to date. These phylogenies usually rely on mitochondrial markers and have limited taxon sampling. Here we investigate the phylogenetic relationships of small barbs of Kenya utilizing cytochrome b, Growth Hormone (GH) intron 2, and RAG1 markers from multiple populations of many species in the region. This multi-locus study produced well-supported phylogenies and revealed additional issues that complicate understanding the relationships among East African barbs. We observed widespread mtDNA introgression within the Kenyan barbs, highlighting the need to include nuclear markers in phylogenetic studies of the group. The GH intron 2 resolved heterospecific individuals and aided in inferring the species level phylogeny. The study reveals unrecognized diversity within the group, including within species reported to occur throughout East Africa, and it provides the groundwork for future taxonomic work in the region and across Africa.

Adding Intra-Articular Growth Hormone to Platelet Rich Plasma under Ultrasound Guidance in Knee Osteoarthritis: A Comparative Double-Blind Clinical Trial

Introduction

Intra-articular injections of platelet rich plasma (PRP) for the treatment of knee osteoarthritis have been shown to reduce pain and improve joint function. The aim of this study is to examine the joint function by adding intra-articular growth hormone to platelet rich plasma. This study was performed on the individuals with knee osteoarthritis and under ultrasound guidance.

Methods

Fifty four patients who were scheduled for ultra-sound guided intra-articular injection were enrolled in the study. The patients were randomly allocated to groups P (platelet rich plasma) and PS (platelet rich plasma and Somatropin). Group P and PS were injected with 5 mL of platelet rich plasma, and 4 IU growth hormone (Somatropin) added to platelet rich plasma, respectively. Intra-articular injection was performed in two steps; the onset of study and one month after. Knee joint function based on Western Ontario and McMaster osteoarthritis index (WOMAC) score at the baseline, 1 and 2 month later, and complications were evaluated.

Results

WOMAC score in both groups has been significantly reduced after injections (P = 0.030). WOMAC score reduction in group PS in first month was significantly higher than group P, but in second month 2, the difference between two groups was not significant (P = 0.235). No complication was observed.

Conclusions

These results showed that adding growth hormone to platelet rich plasma for intra-articular injection improved function of the osteoarthritic knee joint in short period of time.

Height augmentation in 11β-hydroxylase deficiency congenital adrenal hyperplasia

Context

11β-hydroxylase deficiency is the second most common form of congenital adrenal hyperplasia. Untreated, this enzyme deficiency leads to virilization, hypertension, and significant height impairment.

Patient

We describe a patient from abroad who first presented to us at age 7 years for follow-up of ambiguous genitalia. He had been investigated and treated in Pakistan at 3-years-of-age following presentation for bilateral cryptorchidism. He was found to have 46, XX karyotype, elevated 17-OH progesterone and was diagnosed with congenital adrenal hyperplasia. In Pakistan, the patient had abdominal hysterectomy, bilateral salpingoophrectomy, and was started on corticosteroid replacement. At 7 years, shortly after immigrating to Canada, height was 138 cm and BMI 19.3 kg/m² (+2.9 SDS and +1.7 SDS, respectively, male growth chart) and blood pressure was greater than the 99th percentile for age and height. The patient had Prader stage III - IV genital anatomy. Bone age was significantly advanced, yielding a severely compromised predicted final adult height. Biochemical evaluation was consistent with 11β-hydroxylase deficiency congenital adrenal hyperplasia.

Intervention and outcome

In an attempt to improve final height, in addition to glucocorticoid replacement, this patient was treated with recombinant growth hormone and a third generation aromatase inhibitor (Letrozole) with an improvement in final height attained as compared with predicted height.

Conclusions

This case of a 46,XX patient raised as male with congenital adrenal hyperplasia due to 11β-hydroxylase deficiency highlights a number of unique and difficult treatment challenges; specifically, the role of new therapeutic options for optimization of growth in the context of prior suboptimal disease management.

Growth Hormone and Craniofacial Tissues. An update

Growth hormone is an important regulator of bone homeostasis. In childhood, it determines the longitudinal bone growth, skeletal maturation, and acquisition of bone mass. In adulthood, it is necessary to maintain bone mass throughout life. Although an association between craniofacial and somatic development has been clearly established, craniofacial growth involves complex interactions of genes, hormones and environment. Moreover, as an anabolic hormone seems to have an important role in the regulation of bone remodeling, muscle enhancement and tooth development. In this paper the influence of growth hormone on oral tissues is reviewed.

Co-Application of Corticosterone and Growth Hormone Upregulates NR2B Protein and Increases the NR2B:NR2A Ratio and Synaptic Transmission in the Hippocampus

OBJECTIVES

This in vitro study aimed to investigate the possible mechanism underlying the protective effect of growth hormone (GH) on hippocampal function during periods of heightened glucocorticoid exposure.

METHODS

This study was conducted between January and June 2005 at the Joan C. Edwards School of Medicine, Marshall University, in Huntington, West Virginia, USA. The effects of the co-application of GH and corticosterone (CORT) were tested at different concentrations on the field excitatory postsynaptic potentials (fEPSPs) of the hippocampal slices of rats in two different age groups. Changes in the protein expression of N-methyl-D-aspartate receptor (NMDAR) subunits NR1, NR2B and NR2A were measured in hippocampal brain slices treated with either artificial cerebrospinal fluid (ACSF), low doses of CORT alone or both CORT and GH for three hours.

RESULTS

The co-application of CORT and GH was found to have an additive effect on hippocampal synaptic transmission compared to either drug alone. Furthermore, the combined use of low concentrations of GH and CORT was found to have significantly higher effects on the enhancement of fEPSPs in older rats compared to young ones. Both GH and CORT enhanced the protein expression of the NR2A subunit. Simultaneous exposure to low concentrations of GH and CORT significantly enhanced NR2B expression and increased the NR2B:NR2A ratio. In contrast, perfusion with CORT alone caused significant suppression in the NR1 and NR2B protein expression and a decrease in the NR2B:NR2A ratio.

CONCLUSION

These results suggest that NMDARs provide a potential target for mediating the GH potential protective effect against stress and age-related memory and cognitive impairment.

Hormone responses to an acute bout of low intensity blood flow restricted resistance exercise in college-aged females

The purpose of this study was to determine whether the acute hormone response to exercise differed between low intensity blood flow restricted resistance exercise and traditional high-intensity resistance exercise in college-aged women. A total of 13 healthy women (aged 18-25 yrs), who were taking oral contraceptives, volunteered for this randomized crossover study. Subjects performed a session of low intensity blood flow restricted resistance exercise (BFR) (20% of 1-RM, 1 set 30 reps, 2 sets 15 reps) and a session of traditional high intensity resistance exercise without blood flow restriction (HI) (3 sets of 10 repetitions at 80% of 1-RM) on separate days. Fasting serum cortisol and growth hormone (GH) and blood lactate responses were measured in the morning pre and post exercise sessions. GH (Change: HI: 6.34 ± 1.72; BFR: 4.22 ± 1.40 ng·mL(-1)) and cortisol (Change: HI: 4.46 ± 1.53; BFR: 8.10 ± 2.30 ug·dL(-1)) significantly (p < 0.05) increased immediately post exercise for both protocols compared to baseline and there were no significant differences between the protocols for these responses. In contrast, blood lactate levels (HI: 7.35 ± 0.45; BFR: 4.02 ± 0.33 mmol·L(-1)) and ratings of perceived exertion were significantly (p < 0.01) higher for the HI protocol. In conclusion, acute BFR restricted resistance exercise stimulated similar increases in anabolic and catabolic hormone responses in young women. Key PointsGrowth hormone and cortisol levels significantly increased after a single bout of low intensity blood flow restricted resistance exercise in young women.There were no significant differences in hormone responses between the low intensity blood flow restricted protocol and the traditional high intensity higher total workload protocol.Low intensity blood flow restricted resistance exercise provides a sufficient stimulus to elicit anabolic and catabolic hormone responses in young women.

Change in somatostatinergic tone of acromegalic patients according to the size of growth hormone-producing pituitary tumors

The aim of this study was to investigate the relationship between somatostatinergic tone (SST) and the size of growth hormone (GH)-producing pituitary tumors. GH levels of 29 patients with newly diagnosed acromegaly were measured using a 75-gram oral glucose tolerance test (OGTT), an insulin tolerance test (ITT), and an octreotide suppression test (OST). Differences between GH levels during the ITT and the OGTT (ΔGHIO), and between the OGTT and the OST at the same time point (ΔGHOS) were compared according to the size of the tumor and the response pattern to the OST. ΔGHIO of macroadenomas (n=22) was non-significantly higher than those of microadenomas while ΔGHOS of macroadenomas were significantly higher than those of microadenomas. According to further analyses of macroadenomas based on the response pattern to the OST, GH levels during the ITT were significantly higher in non-responders. ΔGHOS showed near-significant differences between responders and non-responders. In conclusion, as the size of the pituitary tumor increases, the effect of glucose on SST appears to be attenuated. Macroadenomas that are non-responders to the OST possess a portion of GH secretion exceeding the range of regulation by SST.

Multimeric growth hormone receptor complexes serve as signaling platforms

Growth hormone (GH) signaling is required for promoting longitudinal body growth, stem cell activation, differentiation, and survival and for regulation of metabolism. Failure to adequately regulate GH signaling leads to disease: excessive GH signaling has been connected to cancer, and GH insensitivity has been reported in cachexia patients. Since its discovery in 1989, the receptor has served a pivotal role as the prototype cytokine receptor both structurally and functionally. Phosphorylation and ubiquitylation regulate the GH receptor (GHR) at the cell surface: two ubiquitin ligases (SCF(βTrCP2) and CHIP) determine the GH responsiveness of cells by controlling its endocytosis, whereas JAK2 initiates the JAK/STAT pathway. We used blue native electrophoresis to identify phosphorylated and ubiquitylated receptor intermediates. We show that GHRs occur as ∼500-kDa complexes that dimerize into active ∼900-kDa complexes upon GH binding. The dimerized complexes act as platforms for transient interaction with JAK2 and ubiquitin ligases. If GH and receptors are made in the same cell (autocrine mode), only limited numbers of ∼900-kDa complexes are formed. The experiments reveal the dynamic changes in post-translational modifications during GH-induced signaling events and show that relatively simple cytokine receptors like GHRs are able to form higher order protein complexes. Insight in the complex formation of cytokine receptors is crucially important for engineering cytokines that control ligand-induced cell responses and for generating a new class of therapeutic agents for a wide range of diseases.

Influence of body mass index on the growth hormone response to provocative testing in short children without growth hormone deficiency

Obesity and its related factors are known to suppress the secretion of growth hormone (GH). We aimed to evaluate the influence of body mass index (BMI) on the peak GH response to provocative testing in short children without GH deficiency. We conducted a retrospective review of medical records of 88 children (2-15 yr old) whose height was less than 3 percentile for one's age and sex, with normal results (peak GH level > 10 ng/mL) of GH provocative testing with clonidine and dopamine. Peak stimulated GH level, height, weight, pubertal status and serum IGF-1 level were measured. Univariate analysis showed that the BMI standard deviation score (SDS) correlated negatively with the natural log (ln) of the peak stimulated GH level (ln peak GH). BMI SDS did not correlate significantly with sex, age, pubertal status, or ln IGF-1 level. BMI SDS correlated negatively with ln peak GH level induced by clonidine but not by dopamine. In stepwise multivariate regression analysis, BMI SDS was the only significant predictor of ln peak GH level in the combination of tests and the clonidine test, but not in the dopamine test. In children without GH deficiency, BMI SDS correlates negatively with the peak GH level. BMI SDS should be included in the analysis of the results of GH provocation tests, especially tests with clonidine.

Increased expression of fibroblast growth factor 21 (FGF21) during chronic undernutrition causes growth hormone insensitivity in chondrocytes by inducing leptin receptor overlapping transcript (LEPROT) and leptin receptor overlapping transcript-like 1 (LEPROTL1) expression

During calorie restriction in mice, increased expression of FGF21 causes growth attenuation and growth hormone (GH) insensitivity. Previous evidence also indicates that fasting-associated increased expression of leptin receptor overlapping transcript (LEPROT) and LEPROT-like 1 (LEPROTL1) (two proteins that regulate intracellular protein trafficking) reduces GH receptor cell-surface expression in the liver. Thus, we hypothesized that FGF21 causes GH insensitivity through regulation of LEPROT and/or LEPROTL1 expression. After 4 weeks of food restriction, LEPROT and LEPROTL1 mRNA expression in the liver and in the tibial growth plate of wild-type (WT) mice was increased compared with WT mice fed ad libitum. In Fgf21 knock-out (KO) mice, LEPROT and LEPROTL1 mRNA expression in food-restricted and fed ad libitum was similar, with the exception of a subgroup of food-restricted Fgf21 KO mice treated with recombinant human (rh) FGF21 that experienced increased LEPROT and LEPROTL1 mRNA expression compared with untreated food-restricted Fgf21 KO mice. In cultured growth plate chondrocytes, FGF21 stimulated LEPROT and LEPROTL1 mRNA expression, with such effect being prevented in chondrocytes transfected with FGFR1 siRNA or ERK1 siRNA. In cells transfected with control siRNA, GH increased [(3)H]thymidine incorporation, collagen X, and IGF-1 mRNA expression, with all effects being prevented by rhFGF21. In addition, rhFGF21 decreased (125)I-GH binding. In LEPROT siRNA- and/or LEPROTL1 siRNA-transfected cells, rhFGF21 did not prevent the GH stimulatory effects on thymidine incorporation, collagen X, and IGF-1 expression; furthermore, rhFGF21 did not prevent (125)I-GH binding. Consistent with the effects of rhFGF21, LEPROT overexpression in chondrocytes resulted in the inhibition of GH action. Our findings indicate that the increased expression of FGF21 during chronic undernutrition inhibits GH action on chondrocytes by activating LEPROT and LEPROTL1.

Diagnostic value of provocative test by insulin combined with clonidine for growth hormone deficiency in children

OBJECTIVE

To evaluate the diagnostic value of provocative test by insulin combined with clonidine for growth hormone deficiency (GHD) during childhood.

METHODS

Eighty children underwent a provocative test with insulin(0.075U/Kg, intravenous) combined with clonidine (4μg/kg, orally). Among them, 40 children underwent clonidine provocative test, 40 children underwent insulin tolerance test (ITT) in another day.

FINDINGS

The specificity of ITT+clonidine test (74%, 88%) was remarkably higher than that of ITT (48%) or clonidine test (65%). ITT+clonidine test had a better accuracy (75%, 85%) than that of ITT (63%) or clonidine test (73%).

CONCLUSION

We conclude that the combined clonidine+insulin test is a feasible, reliable, convenient, time saving, and safe tool for evaluation of the growth hormone (GH) axes than the clonidine test or ITT.

Targeted deletion of growth hormone (GH) receptor in macrophage reveals novel osteopontin-mediated effects of GH on glucose homeostasis and insulin sensitivity in diet-induced obesity

We investigated GH action on macrophage (MΦ) by creating a MΦ-specific GH receptor-null mouse model (MacGHR KO). On a normal diet (10% fat), MacGHR KO and littermate controls exhibited similar growth profiles and glucose excursions on intraperitoneal glucose (ipGTT) and insulin tolerance (ITT) tests. However, when challenged with high fat diet (HFD, 45% fat) for 18 weeks, MacGHR KO mice exhibited impaired ipGTT and ITT compared with controls. In MacGHR KO, adipose-tissue (AT) MΦ abundance was increased with skewing toward M1 polarization. Expression of pro-inflammatory cytokines (IL1β, TNF-α, IL6, and osteopontin (OPN)) were increased in MacGHR KO AT stromal vascular fraction (SVF). In MacGHR KO AT, crown-like-structures were increased with decreased insulin-dependent Akt phosphorylation. The abundance of phosphorylated NF-κB and of OPN was increased in SVF and bone-marrow-derived MΦ in MacGHR KO. GH, acting via an NF-κB site in the distal OPN promoter, inhibited the OPN promoter. Thus in diet-induced obesity (DIO), lack of GH action on the MΦ exerts an unexpected deleterious effect on glucose homeostasis by accentuating AT inflammation and NF-κB-dependent activation of OPN expression. These novel results in mice support the possibility that administration of GH could have salutary effects on DIO-associated chronic inflammation and insulin resistance in humans.

Effect of Arginine Infusion on Ghrelin Secretion in Growth Hormone Sufficient and GH Deficient Children

BACKGROUND

The physiological link between ghrelin and growth hormone (GH) has not yet been fully clarified. Furthermore, the existence of a negative feedback mechanism between growth hormone-insulin-like growth factor (GH-IGF)-I axis and ghrelin and the influence of amino acids on ghrelin secretion in children remain matters of debate.

OBJECTIVES

To understand the regulation of ghrelin secretion and clarify the relationship between ghrelin and GH secretion in GH-deficient (GHD) and GH-sufficient (GHS) children.

PATIENTS AND METHODS

Ten GHD (male/female [M/F], 6/4; age [mean ± SEM], 10.7 ± 0.9 years) and 10 GHS prepubertal children (M/F, 6/4; age [mean ± SEM], 10.3 ± 0.6 years), underwent an arginine (ARG) test (infusion, 0.5 g/kg, iv). Levels of GH, total ghrelin, and acylated ghrelin (AG) were assayed every 30 min from 0 to +120 min.

RESULTS

Peak GH values were lower in GHD subjects than in GHS subjects (P < 0.0001). The baseline levels, peak levels, or area under the curves (AUC) for total ghrelin and AG were similar between GHD and GHS children. ARG infusion was followed by a slight to significant decrease in total ghrelin levels, but not AG levels, both in GHD and GHS subjects with a nadir at +30 min. No correlation was seen between GH, total ghrelin, or AG response and ARG infusion.

CONCLUSIONS

Total ghrelin and AG levels seemed unaffected by GH status in prepubertal children. ARG infusion was unable to blunt ghrelin secretion irrespective of GH status in childhood. Moreover, since ARG influences GH secretion via modulation of somatostatin release, ghrelin secretion seems to be partially refractory to somatostatin action.