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BMC Endocrine Disorders Jul 2023Human growth hormone (hGH) plays a crucial role in growth by binding to growth hormone receptor (GHR) in target cells. Binding of GH molecules to their cognate receptors...
BACKGROUND
Human growth hormone (hGH) plays a crucial role in growth by binding to growth hormone receptor (GHR) in target cells. Binding of GH molecules to their cognate receptors triggers downstream signaling pathways leading to the transcription of several genes, including insulin-like growth factor (IGF)-1. Pathogenic variants in the GHR gene can result in structural and functional defects in the GHR protein, leading to Laron Syndrome (LS) with the primary clinical manifestation of short stature. So far, around 100 GHR variants have been reported, mostly biallelic, as causing LS.
CASE PRESENTATION
We report on three siblings from an Iranian consanguineous family who presented with dwarfism. Whole-exome sequencing (WES) was performed on the proband, revealing a novel homozygous missense variant in the GHR gene (NM_000163.5; c.610 T > A, p.(Trp204Arg)) classified as a likely pathogenic variant according to the recommendation of the American College of Medical Genetics (ACMG). Co-segregation analysis was investigated using Sanger sequencing.
CONCLUSIONS
To date, approximately 400-500 LS cases with GHR biallelic variants, out of them 10 patients originating from Iran, have been described in the literature. Given the high rate of consanguineous marriages in the Iranian population, the frequency of LS is expected to be higher, which might be explained by undiagnosed cases. Early diagnosis of LS is very important, as treatment is available for this condition.
Topics: Humans; Receptors, Somatotropin; Laron Syndrome; Iran; Consanguinity; Pedigree; Human Growth Hormone; Dwarfism; Insulin-Like Growth Factor I
PubMed: 37474955
DOI: 10.1186/s12902-023-01388-1 -
Endocrine-related Cancer Oct 2023The relationship between growth hormone (GH) excess and cancer is a controversial matter. Until 2016, most studies in patients with acromegaly found links with colon and... (Review)
Review
The relationship between growth hormone (GH) excess and cancer is a controversial matter. Until 2016, most studies in patients with acromegaly found links with colon and thyroid neoplasms. However, recent studies found increased risks in gastric, breast, and urinary tract cancer also. Concordantly, clinical situations where GH and insulin-like growth facto-I deficits exist are indeed associated with diminished malignancy incidence. In line with these observations, gain-of-function mutations of various enzymes belonging to the GH and IGF-I signaling pathways have been associated with increased carcinogenesis; similarly, loss-of-function mutations of other enzymes that usually work as tumor repressors are also associated with augmented cancer risk. In a study performed in Ecuador, it was demonstrated that subjects in the Ecuadorian cohort with Laron syndrome (ELS), who have a mutant GH receptor and greatly diminished GH and IGF-I signaling, display diminished incidence of cancer. Along with absent action of GH and IGF-I, ELS individuals also have low serum insulin levels and decreased insulin resistance. Furthermore, hyperglycemia and hyperinsulinemia are indispensable for fast cell mitosis, including that of those cells present in the benign and malignant neoplasms. Notably, and despite their obesity, subjects with the ELS display normoglycemia and hypo-insulinemia, along with diminished incidence of malignancies. We believe that the dual low-IGF-I/low insulin serum levels are responsible for the cancer protection, especially considering that the insulin/INSR signaling is a central site for energy generation in the form of ATP and GDP, which are indispensable for all and every GH/IGF-I physiologic as well as pathologic events.
Topics: Humans; Growth Hormone; Acromegaly; Insulin-Like Growth Factor I; Human Growth Hormone; Insulin; Neoplasms
PubMed: 37428642
DOI: 10.1530/ERC-22-0402 -
Endocrine-related Cancer Sep 2023Many clinical and experimental studies have implicated the growth hormone (GH)-insulin-like growth factor (IGF-1) axis with the progression of cancer. The...
Many clinical and experimental studies have implicated the growth hormone (GH)-insulin-like growth factor (IGF-1) axis with the progression of cancer. The epidemiological finding that patients with Laron syndrome (LS), the best-characterized disease under the spectrum of congenital IGF-1 deficiencies, do not develop cancer is of major scientific and translational relevance. The evasion of LS patients from cancer emphasizes the central role of the GH-IGF-1 system in cancer biology. To identify genes that are differentially expressed in LS and that might provide a biological foundation for cancer protection, we have recently conducted genome-wide profiling of LS patients and normal controls. Analyses were performed on immortalized lymphoblastoid cell lines derived from individual patients. Bioinformatic analyses identified a series of genes that are either over- or under-represented in LS. Differential expression was demonstrated in a number of gene families, including cell cycle, metabolic control, cytokine-cytokine receptor interaction, Jak-STAT and PI3K-AKT signaling, etc. Major differences between LS and controls were also noticed in pathways associated with cell cycle distribution, apoptosis, and autophagy. The identification of novel downstream targets of the GH-IGF-1 network highlights the biological complexity of this hormonal system and sheds light on previously unrecognized mechanistic aspects associated with GH-IGF-1 action in the cancer cell.
Topics: Humans; Growth Hormone; Human Growth Hormone; Insulin-Like Growth Factor I; Laron Syndrome; Neoplasms; Phosphatidylinositol 3-Kinases
PubMed: 37343154
DOI: 10.1530/ERC-22-0394 -
Biomolecules Mar 2023Laron syndrome (LS) is a rare genetic disorder characterized by low levels of insulin-like growth factor 1 (IGF1) and high levels of growth hormone (GH) due to mutations...
Laron syndrome (LS) is a rare genetic disorder characterized by low levels of insulin-like growth factor 1 (IGF1) and high levels of growth hormone (GH) due to mutations in the growth hormone receptor gene (). A -knockout (-KO) pig was developed as a model for LS, which displays many of the same features as humans with LS-like transient juvenile hypoglycemia. This study aimed to investigate the effects of impaired GHR signaling on immune functions and immunometabolism in -KO pigs. GHR are located on various cell types of the immune system. Therefore, we investigated lymphocyte subsets, proliferative and respiratory capacity of peripheral blood mononuclear cells (PBMCs), proteome profiles of CD4 and CD4 lymphocytes and IFN-α serum levels between wild-type (WT) controls and -KO pigs, which revealed significant differences in the relative proportion of the CD4CD8α subpopulation and in IFN-α levels. We detected no significant difference in the respiratory capacity and the capacity for polyclonal stimulation in PBMCs between the two groups. But proteome analysis of CD4 and CD4 lymphocyte populations revealed multiple significant protein abundance differences between -KO and WT pigs, involving pathways related to amino acid metabolism, beta-oxidation of fatty acids, insulin secretion signaling, and oxidative phosphorylation. This study highlights the potential use of -KO pigs as a model for studying the effects of impaired GHR signaling on immune functions.
Topics: Humans; Animals; Swine; Receptors, Somatotropin; Laron Syndrome; Leukocytes, Mononuclear; Proteome; Growth Hormone
PubMed: 37189345
DOI: 10.3390/biom13040597 -
FEBS Open Bio Jul 2023Chagas disease (CD) is one of the most devasting parasitic diseases in the Americas, affecting 7-8 million people worldwide. In vitro and in vivo experiments have...
Chagas disease (CD) is one of the most devasting parasitic diseases in the Americas, affecting 7-8 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 Trypanosoma cruzi infection. We infected mouse fibroblast L-cells with T. 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 with 48% from control wild-type mouse serum (WT). Treatment with bGH mouse serum significantly decreased infection of cells by 41% compared with 54% from WT controls. Our results suggest that high GH and low IGF-1 in blood circulation, as typically seen in LS individuals, confer 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).
Topics: Mice; Humans; Animals; Cattle; Insulin-Like Growth Factor I; Growth Hormone; Receptors, Somatotropin; Mice, Transgenic; Chagas Disease
PubMed: 37163287
DOI: 10.1002/2211-5463.13627 -
Journal of Neuroendocrinology Apr 2023Growth hormone receptor deficiency (GHRD) results in low serum insulin-like growth factor 1 (IGF1) and high, but non-functional serum growth hormone (GH) levels in human...
Growth hormone receptor deficiency (GHRD) results in low serum insulin-like growth factor 1 (IGF1) and high, but non-functional serum growth hormone (GH) levels in human Laron syndrome (LS) patients and animal models. This study investigated the quantitative histomorphological and molecular alterations associated with GHRD. Pituitary glands from 6 months old growth hormone receptor deficient (GHR-KO) and control pigs were analyzed using a quantitative histomorphological approach in paraffin (9 GHR-KO [5 males, 4 females] vs. 11 controls [5 males, 6 females]), ultrathin sections tissue sections (3 male GHR-KO vs. 3 male controls) and label-free proteomics (4 GHR-KO vs. 4 control pigs [2 per sex]). GHR-KO pigs displayed reduced body weights (60% reduction in comparison to controls; p < .0001) and decreased pituitary volumes (54% reduction in comparison to controls; p < .0001). The volume proportion of the adenohypophysis did not differ in GHR-KO and control pituitaries (65% vs. 71%; p = .0506) and GHR-KO adenohypophyses displayed a reduced absolute volume but an unaltered volume density of somatotrophs in comparison to controls (21% vs. 18%; p = .3164). In GHR-KO pigs, somatotroph cells displayed a significantly reduced volume density of granules (23.5%) as compared to controls (67.7%; p < .0001). Holistic proteome analysis of adenohypophysis samples identified 4660 proteins, of which 592 were differentially abundant between the GHR-KO and control groups. In GHR-KO samples, the abundance of somatotropin precursor was decreased, whereas increased abundances of proteins involved in protein production, transport and endoplasmic reticulum (ER) stress were revealed. Increased protein production and secretion as well as significantly reduced proportion of GH-storing granules in somatotroph cells of the adenohypophysis without an increase in volume density of somatotroph cells in the adenohypophysis could explain elevated serum GH levels in GHR-KO pigs.
PubMed: 37160285
DOI: 10.1111/jne.13277 -
Frontiers in Endocrinology 2023Linear growth during childhood is the result of the synergic contribution of different factors. The best growth determinant system during each period of life is... (Review)
Review
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.
Topics: Dwarfism; Human Growth Hormone; Insulin-Like Growth Factor I; Humans; Growth Disorders
PubMed: 37008935
DOI: 10.3389/fendo.2023.1141039 -
Cellular and Molecular Life Sciences :... Mar 2023Signal transducer and activator of transcription (STAT) proteins act downstream of cytokine receptors to facilitate changes in gene expression that impact a range of...
Signal transducer and activator of transcription (STAT) proteins act downstream of cytokine receptors to facilitate changes in gene expression that impact a range of developmental and homeostatic processes. Patients harbouring loss-of-function (LOF) STAT5B mutations exhibit postnatal growth failure due to lack of responsiveness to growth hormone as well as immune perturbation, a disorder called growth hormone insensitivity syndrome with immune dysregulation 1 (GHISID1). This study aimed to generate a zebrafish model of this disease by targeting the stat5.1 gene using CRISPR/Cas9 and characterising the effects on growth and immunity. The zebrafish Stat5.1 mutants were smaller, but exhibited increased adiposity, with concomitant dysregulation of growth and lipid metabolism genes. The mutants also displayed impaired lymphopoiesis with reduced T cells throughout the lifespan, along with broader disruption of the lymphoid compartment in adulthood, including evidence of T cell activation. Collectively, these findings confirm that zebrafish Stat5.1 mutants mimic the clinical impacts of human STAT5B LOF mutations, establishing them as a model of GHISID1.
Topics: Animals; Humans; Zebrafish; STAT5 Transcription Factor; Laron Syndrome; Mutation; Growth Hormone
PubMed: 36995466
DOI: 10.1007/s00018-023-04759-y -
Endocrine-related Cancer Jun 2023Meta-analyses from 2018-2022 have shown that obesity increases the risk of various cancers such as acute myeloid lymphoma, chronic myeloid lymphoma, diffuse beta cell...
Meta-analyses from 2018-2022 have shown that obesity increases the risk of various cancers such as acute myeloid lymphoma, chronic myeloid lymphoma, diffuse beta cell lymphoma, Hodgkin's lymphoma, leukemia, multiple myeloma, non-Hodgkin's lymphoma, bladder, breast, cholangiocarcinoma, colorectal, ovarian, esophageal, kidney, liver, prostate, thyroid, and uterus. Contextually, obesity, and its comorbidities, is the largest, most lethal pandemics in the history of mankind; hence, identification of underlying mechanisms is needed to adequately address this global health threat. Herein, we present the metabolic and hormonal mechanisms linked to obesity that might etiologically contribute to neoplasia, including hyperinsulinemia and putative places in the insulin-signaling pathway. Excess insulin, acting as a growth factor, might contribute to tumorigenesis, while abundant ATP and GDP supply the additional energy needed for proliferation of rapidly dividing cells. Our observations in the Ecuadorian cohort of subjects with Laron syndrome (ELS) prove that obesity does not always associate with increased cancer risk. Indeed, despite excess body fat from birth to death, these individuals display a diminished incidence of cancer when compared to their age- and sex-matched relatives. Furthermore, in cell cultures exposed to potent oxidizing agents, addition of ELS serum induces less DNA damage as well as increased apoptosis. ELS individuals have absent growth hormone (GH) counter-regulatory effects in carbohydrate metabolism due to a defective GH receptor. The corresponding biochemical phenotype includes extremely low basal serum concentrations of insulin and insulin-like growth factor-I, lower basal glucose and triglyceride (TG) levels, and diminished glucose, TG, and insulin responses to orally administered glucose or to a mixed meal.
Topics: Male; Female; Humans; Laron Syndrome; Ecuador; Insulin-Like Growth Factor I; Insulin; Neoplasms; Obesity; Glucose
PubMed: 36971780
DOI: 10.1530/ERC-22-0389 -
Journal of Pediatric Endocrinology &... May 2023Laron dwarfism is a rare genetic disorder first reported among Israeli jewish children, subsequently about 350 cases cases have been reported worldwide. We aim to...
OBJECTIVES
Laron dwarfism is a rare genetic disorder first reported among Israeli jewish children, subsequently about 350 cases cases have been reported worldwide. We aim to describe the clinical profile of nine children with Laron dwarfism from Institute of Child Health, Chennai.
METHODS
Analysis of case records from 2010 to 2018.
RESULTS
Male:female ratio is 6:3. Mean age of the children at the time of diagnosis was 3 years. All children were extremely short, and mean height Z score (SD) was -7.7(0.8). All children had characteristic facies with no hypoglycaemic episodes. Microcephaly was present in four children out of which two had developmental delay. Three out of six boys had micropenis. All children had low insulin like growth factor-1 (IGF-1) and high basal growth hormone (GH) with a mean (SD) of 39.6 (11.2) ng/mL.
CONCLUSIONS
Suspicion of Laron syndrome should be high when child presents with features of Growth Hormone Deficiency (GHD) with extreme stunting.
Topics: Child; Humans; Male; Female; Child, Preschool; Laron Syndrome; Tertiary Healthcare; India; Growth Hormone; Dwarfism, Pituitary; Insulin-Like Growth Factor I; Dwarfism
PubMed: 36957988
DOI: 10.1515/jpem-2022-0538