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McDougle JM, Mangine GT, Townsend JR, Jajtner AR, Feito Y. Acute physiological outcomes of high-intensity functional training: a scoping review. PeerJ 2023; 11:e14493. [PMID: 36620744 PMCID: PMC9817969 DOI: 10.7717/peerj.14493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 11/09/2022] [Indexed: 01/04/2023] Open
Abstract
Background Systematic reviews and meta-analyses related to high-intensity functional training (HIFT) have been conducted. However, due to a restricted pool of available research, these investigations are often limited in scope. As such, a scoping review investigating the present literature surrounding the acute physiological response to HIFT-based exercise was chosen as a more appropriate structured review. Methodology A scoping review was conducted following Arksey and O'Malley's framework. Three large scale databases were searched to reveal any article pertaining to HIFT and related exercise terminology. Results A total of 2,241 articles were found during the initial search. Following this, titles, then abstracts, and full-texts were reviewed to determine inclusion eligibility. A total of 60 articles which investigated a combined total of 35 unique HIFT workouts were included within this review. Conclusions A variety of physiological parameters and HIFT workouts have been examined. Markers of intensity (e.g., blood lactate concentrations, heart rate) have been most consistently assessed across all studies, and these support the idea that HIFT workouts are typically performed at high-intensity. In contrast, the inclusion of most other measures (e.g., hormonal, markers of inflammation and damage, energy expenditure, performance) has been inconsistent and has thus, limited the possibility for making generalized conclusions. Differences in study methodologies have further impacted conclusions, as different studies have varied in sample population characteristics, workouts assessed, and time points. Though it may be impossible to comprehensively research all possible HIFT workouts, consistent adoption of population definitions and workload quantification may overcome this challenge and assist with future comparisons.
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Affiliation(s)
- Jacob M. McDougle
- Exercise Science and Sport Management, Kennesaw State University, Kennesaw, GA, United States
| | - Gerald T. Mangine
- Exercise Science and Sport Management, Kennesaw State University, Kennesaw, GA, United States
| | - Jeremy R. Townsend
- Exercise and Nutrition Science, Lipscomb University, Nashville, TN, United States
| | - Adam R. Jajtner
- Exercise Physiology, Kent State University, Kent, OH, United States
| | - Yuri Feito
- Exercise Science and Sport Management, Kennesaw State University, Kennesaw, GA, United States,American College of Sports Medicine, Indianapolis, IN, United States
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Fadel IM, Ragab MH, Eid OM, Helmy NA, El-Bassyouni HT, Mazen I. IGF1R, IGFALS, and IGFBP3 gene copy number variations in a group of non-syndromic Egyptian short children. J Genet Eng Biotechnol 2021; 19:109. [PMID: 34322776 PMCID: PMC8319271 DOI: 10.1186/s43141-021-00202-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Accepted: 06/27/2021] [Indexed: 11/10/2022]
Abstract
Background Insulin-like growth factor-1 (IGF-1) is required for normal intrauterine and postnatal growth, and this action is mediated through IGF1 receptor (IGF1R). IGF1R copy number variants (CNVs) can cause pre- and postnatal growth restriction, affecting an individual’s height. In this study, we used multiplex ligation-dependent probe amplification (MLPA) to detect CNVs in IGF1R, IGFALS, and IGFBP3 genes in the diagnostic workup of short stature for 40 Egyptian children with short stature. Results We detected a heterozygous deletion of IGF1R (exons 4 through 21) in 1 out of the 40 studied children (2.5%). Meanwhile, we did not detect any CNVs in either IGFALS or IGFBP3. Conclusion The diagnostic workup of short stature using MLPA for CNVs of IGF1R and other recognized height-related genes, such as SHOX and GH, in non-syndromic short stature children can be a fast and inexpensive diagnostic tool to recognize a subcategory of patients in which growth hormone treatment can be considered.
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Affiliation(s)
- Islam M Fadel
- Department of Human Cytogenetics, National Research Centre, El Buhouth St., Dokki, Cairo, 12622, Egypt.
| | - Moustafa H Ragab
- Department of Medical Environmental Research, Institute of Environmental Studies and Research, Ain Shams University, El Khalifa El Maamon Street, Cairo, 12622, Egypt
| | - Ola M Eid
- Department of Human Cytogenetics, National Research Centre, El Buhouth St., Dokki, Cairo, 12622, Egypt
| | - Nivine A Helmy
- Department of Human Cytogenetics, National Research Centre, El Buhouth St., Dokki, Cairo, 12622, Egypt
| | - Hala T El-Bassyouni
- Department of Clinical Genetics, National Research Centre, El Bohouth Street, Dokki, Cairo, 12622, Egypt
| | - Inas Mazen
- Department of Clinical Genetics, National Research Centre, El Bohouth Street, Dokki, Cairo, 12622, Egypt
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3
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Perchard R, Murray PG, Payton A, Highton GL, Whatmore A, Clayton PE. Novel Mutations and Genes That Impact on Growth in Short Stature of Undefined Aetiology: The EPIGROW Study. J Endocr Soc 2020; 4:bvaa105. [PMID: 32939436 PMCID: PMC7482646 DOI: 10.1210/jendso/bvaa105] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 08/24/2020] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Children with short stature of undefined aetiology (SS-UA) may have undiagnosed genetic conditions. PURPOSE To identify mutations causing short stature (SS) and genes related to SS, using candidate gene sequence data from the European EPIGROW study. METHODS First, we selected exonic single nucleotide polymorphisms (SNPs), in cases and not controls, with minor allele frequency (MAF) < 2%, whose carriage fitted the mode of inheritance. Known mutations were identified using Ensembl and gene-specific databases. Variants were classified as pathogenic, likely pathogenic, or variant of uncertain significance using criteria from the American College of Medical Genetics and Genomics and the Association for Molecular Pathology. If predicted by ≥ 5/10 algorithms (eg, Polyphen2) to be deleterious, this was considered supporting evidence of pathogenicity. Second, gene-based burden testing determined the difference in SNP frequencies between cases and controls across all and then rare SNPs. For genotype/phenotype relationships, we used PLINK, based on haplotype, MAF > 2%, genotype present in > 75%, and Hardy Weinberg equilibrium P > 10-4. RESULTS First, a diagnostic yield of 10% (27/263) was generated by 2 pathogenic (nonsense in ACAN) and a further 25 likely pathogenic mutations, including previously known missense mutations in FANCB, IGFIR, MMP13, NPR2, OBSL1, and PTPN11. Second, genes related to SS: all methods identified PEX2. Another 7 genes (BUB1B, FANCM, CUL7, FANCA, PTCH1, TEAD3, BCAS3) were identified by both gene-based approaches and 6 (A2M, EFEMP1, PRKCH, SOS2, RNF135, ZBTB38) were identified by gene-based testing for all SNPs and PLINK. CONCLUSIONS Such panels improve diagnosis in SS-UA, extending known disease phenotypes. Fourteen genes related to SS included some known to cause growth disorders as well as novel targets.
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Affiliation(s)
- Reena Perchard
- Developmental Biology & Medicine, Faculty of Biology, Medicine & Health, University of Manchester and Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Philip George Murray
- Developmental Biology & Medicine, Faculty of Biology, Medicine & Health, University of Manchester and Manchester Academic Health Science Centre, Manchester, United Kingdom
- Department of Paediatric Endocrinology, Manchester University NHS Foundation Trust, Manchester, United Kingdom
| | - Antony Payton
- Informatics, Imaging & Data Science, Faculty of Biology, Medicine & Health, University of Manchester, Manchester, United Kingdom
| | - Georgina Lee Highton
- Developmental Biology & Medicine, Faculty of Biology, Medicine & Health, University of Manchester and Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Andrew Whatmore
- Developmental Biology & Medicine, Faculty of Biology, Medicine & Health, University of Manchester and Manchester Academic Health Science Centre, Manchester, United Kingdom
| | - Peter Ellis Clayton
- Developmental Biology & Medicine, Faculty of Biology, Medicine & Health, University of Manchester and Manchester Academic Health Science Centre, Manchester, United Kingdom
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Gkourogianni A, Andrade AC, Jonsson B, Segerlund E, Werner‐Sperker A, Horemuzova E, Dahlgren J, Burstedt M, Nilsson O. Pre- and postnatal growth failure with microcephaly due to two novel heterozygous IGF1R mutations and response to growth hormone treatment. Acta Paediatr 2020; 109:2067-2074. [PMID: 32037650 DOI: 10.1111/apa.15218] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 01/21/2020] [Accepted: 02/07/2020] [Indexed: 11/29/2022]
Abstract
AIM To explore the phenotype and response to growth hormone in patients with heterozygous mutations in the insulin-like growth factor I receptor gene (IGF1R). METHODS Children with short stature, microcephaly, born SGA combined with biochemical sign of IGF-I insensitivity were analysed for IGF1R mutations or deletions using Sanger sequencing and Multiple ligation-dependent probe amplification analysis. RESULTS In two families, a novel heterozygous non-synonymous missense IGF1R variant was identified. In family 1, c.3364G > T, p.(Gly1122Cys) was found in the proband and co-segregated perfectly with the phenotype in three generations. In family 2, a de novo variant c.3530G > A, p.(Arg1177His) was detected. Both variants were rare, not present in the GnomAD database. Three individuals carrying IGF1R mutations have received rhGH treatment. The average gain in height SDS during treatment was 0.42 (range: 0.26-0.60) and 0.64 (range: 0.32-0.86) after 1 and 2 years of treatment, respectively. CONCLUSION Our study presents two heterozygous IGF1R mutations causing pre- and postnatal growth failure and microcephaly and also indicates that individuals with heterozygous IGF1R mutations can respond to rhGH treatment. The findings highlight that sequencing of the IGF1R should be considered in children with microcephaly and short stature due to pre- and postnatal growth failure.
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Affiliation(s)
- Alexandra Gkourogianni
- Division of Pediatric Endocrinology Department of Women’s and Children’s Health Karolinska Institutet and University Hospital Stockholm Sweden
- Center for Molecular Medicine Karolinska Institutet and University Hospital Stockholm Sweden
| | - Anenisia C. Andrade
- Division of Pediatric Endocrinology Department of Women’s and Children’s Health Karolinska Institutet and University Hospital Stockholm Sweden
- Center for Molecular Medicine Karolinska Institutet and University Hospital Stockholm Sweden
| | - Björn‐Anders Jonsson
- Department of Medical Biosciences Medical and Clinical Genetics Umeå University Umeå Sweden
| | - Emma Segerlund
- Department of Pediatrics Sunderby Hospital Sunderby Sweden
| | | | - Eva Horemuzova
- Division of Pediatric Endocrinology Department of Women’s and Children’s Health Karolinska Institutet and University Hospital Stockholm Sweden
| | - Jovanna Dahlgren
- Göteborg Pediatric Growth Research Center Department of Pediatrics Institute of Clinical Sciences Sahlgrenska AcademyUniversity of Gothenburg Göteborg Sweden
| | - Magnus Burstedt
- Department of Medical Biosciences Medical and Clinical Genetics Umeå University Umeå Sweden
| | - Ola Nilsson
- Division of Pediatric Endocrinology Department of Women’s and Children’s Health Karolinska Institutet and University Hospital Stockholm Sweden
- Center for Molecular Medicine Karolinska Institutet and University Hospital Stockholm Sweden
- School of Medical Sciences Örebro University and University Hospital Örebro Sweden
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Collett-Solberg PF, Jorge AAL, Boguszewski MCS, Miller BS, Choong CSY, Cohen P, Hoffman AR, Luo X, Radovick S, Saenger P. Growth hormone therapy in children; research and practice - A review. Growth Horm IGF Res 2019; 44:20-32. [PMID: 30605792 DOI: 10.1016/j.ghir.2018.12.004] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 12/24/2018] [Indexed: 01/15/2023]
Abstract
Short stature remains the most common reason for referral to a pediatric Endocrinologist and its management remains a challenge. One of the main controversies is the diagnosis of idiopathic short stature and the role of new technologies for genetic investigation of children with inadequate growth. Complexities in management of children with short stature includes selection of who should receive interventions such as recombinant human growth hormone, and how should this agent dose be adjusted during treatment. Should anthropometrical data be the primary determinant or should biochemical and genetic data be used to improve growth response and safety? Furthermore, what is considered a suboptimal response to growth hormone therapy and how should this be managed? Treatment of children with short stature remains a "hot" topic and more data is needed in several areas. These issues are reviewed in this paper.
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Affiliation(s)
- Paulo Ferrez Collett-Solberg
- Pediatric Endocrinology, Departamento de Medicina Interna, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro (UERJ), Rio de Janeiro, RJ, Brazil.
| | - Alexander A L Jorge
- Faculdade de Medicina, Universidade de São Paulo (FMUSP), the Endocrinology Division/Genetic Endocrinology Unit (LIM 25), Brazil.
| | | | - Bradley S Miller
- Pediatric Endocrinology, University of Minnesota Masonic Children's Hospital, USA.
| | - Catherine Seut Yhoke Choong
- Division of Pediatrics School of Medicine, Perth Childrens Hospital, University of Western Australia, Australia.
| | - Pinchas Cohen
- Dean, Leonard Davis School of Gerontology, University of Southern California, Los Angeles, CA, USA.
| | - Andrew R Hoffman
- Senior Vice Chair for Academic Affairs, Department of Medicine, Stanford University, USA.
| | - Xiaoping Luo
- Department of Pediatrics, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
| | - Sally Radovick
- Department of Pediatrics, Senior Associate Dean for Clinical and Translational Research, Robert Wood Johnson Medical School, USA.
| | - Paul Saenger
- New York University Winthrop Hospital, 101 Mineola Boulevard, Mineola, NY 11201, USA.
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Miletta MC, Flück CE, Mullis PE. Targeting GH-1 splicing as a novel pharmacological strategy for growth hormone deficiency type II. Biochem Pharmacol 2017; 124:1-9. [PMID: 27457999 DOI: 10.1016/j.bcp.2016.07.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Accepted: 07/21/2016] [Indexed: 10/21/2022]
Abstract
Isolated growth hormone deficiency type II (IGHD II) is a rare genetic splicing disorder characterized by reduced growth hormone (GH) secretion and short stature. It is mainly caused by autosomal dominant-negative mutations within the growth hormone gene (GH-1) which results in missplicing at the mRNA level and the subsequent loss of exon 3, producing the 17.5-kDa GH isoform: a mutant and inactive GH protein that reduces the stability and the secretion of the 22-kDa GH isoform, the main biologically active GH form. At present, patients suffering from IGHD II are treated with daily injections of recombinant human GH (rhGH) in order to reach normal height. However, this type of replacement therapy, although effective in terms of growth, does not prevent the toxic effects of the 17.5-kDa mutant on the pituitary gland, which may eventually lead to other hormonal deficiencies. As the severity of the disease inversely correlates with the 17.5-kDa/22-kDa ratio, increasing the inclusion of exon 3 is expected to ameliorate disease symptoms. This review focuses on the recent advances in experimental and therapeutic strategies applicable to treat IGHD II in clinical and preclinical contexts. Several avenues for alternative IGHD II therapy will be discussed including the use of small interfering RNA (siRNA) and short hairpin RNA (shRNA) constructs that specifically target the exon 3-deleted transcripts as well as the application of histone deacetylase inhibitors (HDACi) and antisense oligonucleotides (AONs) to enhance full-length GH-1 transcription, correct GH-1 exon 3 splicing and manipulate GH pathway.
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Affiliation(s)
- Maria Consolata Miletta
- Division of Paediatric Endocrinology, Diabetology and Metabolism, Department of Pediatrics and Department of Clinical Research, Inselspital, Bern University Hospital, University of Bern, Switzerland.
| | - Christa E Flück
- Division of Paediatric Endocrinology, Diabetology and Metabolism, Department of Pediatrics and Department of Clinical Research, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - Primus-E Mullis
- Division of Paediatric Endocrinology, Diabetology and Metabolism, Department of Pediatrics and Department of Clinical Research, Inselspital, Bern University Hospital, University of Bern, Switzerland
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7
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Abstract
Resumen
En bovinos, la reducción de la eficiencia reproductiva de los sistemas de producción de carne y doble propósito se atribuye a factores nutricionales, sanitarios, climáticos y en última instancia a características genéticas de los animales. Sin embargo, en condiciones de trópico cálido húmedo, variaciones genéticas entre razas podrían reducir la edad al primer parto, el intervalo entre partos y aumentar la vida útil de las vacas. Las razas Sanmartinero y Casanareño podrían mejorar los sistemas de producción bovina debido al aporte de variantes genéticas que emergieron en el proceso de adaptación a las duras condiciones de la Orinoquía Colombiana. Actualmente, los genes con función biológica conocida se usan como marcadores moleculares para estimar parámetros de diversidad genética pecuaria facilitando la identificación y ubicación dentro del genoma de regiones que codifican o regulan la expresión de rasgos de interés económico. En ganado criollo colombiano Romosinuano se han identificado genes candidatos del eje Hormona de crecimiento/Factor de crecimiento similar a la insulina que se asocian positivamente con edad al primer parto, intervalo entre partos, longevidad y protección del embrión al estrés calórico. No obstante en las razas criollas Sanmartinero y Casanareño reconocidas empíricamente por estas características, no han sido sometidas a dichos análisis de genes candidatos que permitan promover un valor agregado a los animales. El objetivo de esta revisión es documentar algunos parámetros reproductivos y genéticos de las razas criollas Sanmartinero y Casanareño que soportan la necesidad de desarrollar estudios moleculares y justificar su uso en los sistemas de producción de carne y doble propósito de la Orinoquía colombiana.
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Lindsey RC, Mohan S. Skeletal effects of growth hormone and insulin-like growth factor-I therapy. Mol Cell Endocrinol 2016; 432:44-55. [PMID: 26408965 PMCID: PMC4808510 DOI: 10.1016/j.mce.2015.09.017] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 09/21/2015] [Accepted: 09/22/2015] [Indexed: 10/23/2022]
Abstract
The growth hormone/insulin-like growth factor (GH/IGF) axis is critically important for the regulation of bone formation, and deficiencies in this system have been shown to contribute to the development of osteoporosis and other diseases of low bone mass. The GH/IGF axis is regulated by a complex set of hormonal and local factors which can act to regulate this system at the level of the ligands, receptors, IGF binding proteins (IGFBPs), or IGFBP proteases. A combination of in vitro studies, transgenic animal models, and clinical human investigations has provided ample evidence of the importance of the endocrine and local actions of both GH and IGF-I, the two major components of the GH/IGF axis, in skeletal growth and maintenance. GH- and IGF-based therapies provide a useful avenue of approach for the prevention and treatment of diseases such as osteoporosis.
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Affiliation(s)
- Richard C Lindsey
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA; Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA; Department of Biochemistry, Loma Linda University, Loma Linda, CA 92354, USA
| | - Subburaman Mohan
- Musculoskeletal Disease Center, Loma Linda VA Healthcare System, Loma Linda, CA 92357, USA; Department of Medicine, Loma Linda University, Loma Linda, CA 92354, USA; Department of Biochemistry, Loma Linda University, Loma Linda, CA 92354, USA.
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Arroba AI, Rodríguez-de la Rosa L, Murillo-Cuesta S, Vaquero-Villanueva L, Hurlé JM, Varela-Nieto I, Valverde ÁM. Autophagy resolves early retinal inflammation in Igf1-deficient mice. Dis Model Mech 2016; 9:965-74. [PMID: 27483352 PMCID: PMC5047685 DOI: 10.1242/dmm.026344] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Accepted: 07/04/2016] [Indexed: 01/20/2023] Open
Abstract
Insulin-like growth factor-1 (IGF-1) is a growth factor with differentiating, anti-apoptotic and metabolic functions in the periphery, and anti-inflammatory properties in the nervous system. Mice that have mutations in the Igf1 gene, rendering the gene product inactive (Igf1−/−), present with age-related visual loss accompanied by structural alterations in the first synapses of the retinal pathway. Recent advances have revealed a crucial role of autophagy in immunity and inflammation. Keeping in mind this close relationship, we aimed to decipher these processes in the context of the defects that occur during ageing in the retina of Igf1−/− mice. Tnfa and Il1b mRNAs, and phosphorylation of JNK and p38 MAPK were elevated in the retinas of 6- and 12-month old Igf1−/− mice compared to those in age-matched Igf1+/+ controls. In 6-month-old Igf1−/− retinas, increased mRNA levels of the autophagy mediators Becn1, Atg9, Atg5 and Atg4, decreased p62 (also known as SQSTM1) protein expression together with an increased LC3-II:LC3-I ratio reflected active autophagic flux. However, in retinas from 12-month-old Igf1−/− mice, Nlrp3 mRNA, processing of the IL1β pro-form and immunostaining of active caspase-1 were elevated compared to those in age-matched Igf1+/+ controls, suggesting activation of the inflammasome. This effect concurred with accumulation of autophagosomes and decreased autophagic flux in the retina. Microglia localization and status of activation in the retinas of 12-month-old Igf1+/+ and Igf1−/− mice, analyzed by immunostaining of Cd11b and Iba-1, showed a specific distribution pattern in the outer plexiform layer (OPL), inner plexiform layer (IPL) and inner nuclear layer (INL), and revealed an increased number of activated microglia cells in the retina of 12-month-old blind Igf1−/− mice. Moreover, reactive gliosis was exclusively detected in the retinas from 12-month-old blind Igf1−/− mice. In conclusion, this study provides new evidence in a mouse model of IGF-1 deficiency that autophagy is an adaptive response that might confer protection against persistent inflammation in the retina during ageing. Summary:Igf1-deficient mice show chronic inflammation in the retina, and we reveal that controlling inflammation through autophagy in young mice could prevent loss of retinal function.
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Affiliation(s)
- Ana I Arroba
- Alberto Sols Biomedical Research Institute (IIBm) (CSIC/UAM), 28029, Madrid, Spain Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERdem), ISCIII, 28029, Madrid, Spain
| | - Lourdes Rodríguez-de la Rosa
- Alberto Sols Biomedical Research Institute (IIBm) (CSIC/UAM), 28029, Madrid, Spain Biomedical Research Networking Centre on Rare Diseases (CIBERER), ISCIII, 28029, Madrid, Spain IdiPAZ Institute for Health Research, Madrid 28029, Spain
| | - Silvia Murillo-Cuesta
- Alberto Sols Biomedical Research Institute (IIBm) (CSIC/UAM), 28029, Madrid, Spain Biomedical Research Networking Centre on Rare Diseases (CIBERER), ISCIII, 28029, Madrid, Spain IdiPAZ Institute for Health Research, Madrid 28029, Spain
| | | | - Juan M Hurlé
- Departamento de Anatomía y Biología Celular and IDIVAL, Universidad de Cantabria, 39011, Santander, Spain
| | - Isabel Varela-Nieto
- Alberto Sols Biomedical Research Institute (IIBm) (CSIC/UAM), 28029, Madrid, Spain Biomedical Research Networking Centre on Rare Diseases (CIBERER), ISCIII, 28029, Madrid, Spain IdiPAZ Institute for Health Research, Madrid 28029, Spain
| | - Ángela M Valverde
- Alberto Sols Biomedical Research Institute (IIBm) (CSIC/UAM), 28029, Madrid, Spain Spanish Biomedical Research Centre in Diabetes and Associated Metabolic Disorders (CIBERdem), ISCIII, 28029, Madrid, Spain IdiPAZ Institute for Health Research, Madrid 28029, Spain
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10
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Nijim Y, Awni Y, Adawi A, Bowirrat A. Classic Case Report of Donohue Syndrome (Leprechaunism; OMIM *246200): The Impact of Consanguineous Mating. Medicine (Baltimore) 2016; 95:e2710. [PMID: 26871809 PMCID: PMC4753905 DOI: 10.1097/md.0000000000002710] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 01/13/2016] [Accepted: 01/14/2016] [Indexed: 01/08/2023] Open
Abstract
Donohue syndrome ([DS]; leprechaunism) describes a genetic autosomal recessive disorder that results from the presence of homozygous or compound heterozygous mutations in the insulin receptor gene (INSR; 19p13.3-p13.2).Donohue syndrome is associated with a fatal congenital form of dwarfism with features of intrauterine and postnatal growth retardation, exaggerated hyperglycemia with hyperinsulinism and dysmorphic abnormalities.We present a case of DS owing to the rarity of this syndrome (1 case in every million births). We discuss how the disease presents, its genetic underpinning, and its prevention.The case was encountered in an Arab male born on 1 September, 2014, for consanguineous parents. The delivery was via cesarean section at 37 weeks gestation due to severe intrauterine growth restriction and nonprogress labor term. The patient was admitted to the Neonatal Intensive Care Unit due to infection, and jaundice. Dysmorphic features, abnormalities of the craniofacial region, low birth weight, skin abnormalities, abdominal distension and hypertrichosis were observed. Laboratory examinations showed, hyperinsulinism, increased C-peptide, thrombocytopenia, leucopenia, and anemia.The diagnosis of DS was done based on the combinations of typical dysmorphic characteristics, clinical evaluation, supported by genetic analysis and exaggerated biochemical results. Genetic diagnosis of DS was performed through analysis of DNA via polymerase chain reaction (PCR). A qualitative real-time PCR was used, to monitor the amplification of a targeted DNA molecule during the PCR. Other technique using sequencing of the INSR gene, which permits genetic diagnosis, counseling, and antenatal diagnoses in subsequent pregnancies, were also performed.Treatment of DS is supportive and requires the combined efforts of a multidisciplinary team, which include pediatricians, endocrinologists, dermatologists, and other health care professionals. Currently, treatment with recombinant insulin-like growth factor 1 demonstrates effectiveness, and a combination treatment with insulin-like growth factor binding protein 3 resulted in an increased lifespan.There is a scarcity of genetic information on DS among the Arab population. Consanguinity is one of underlying reasons for the appearance of rare genetic disorders. Inbreeding has long been considered a controversial phenomenon. Genetic counseling and overwhelming the alertness of the negative consequences of consanguinity on public health are warranted.
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Affiliation(s)
- Yousif Nijim
- From the Pediatric and Neonatal Department, EMMS Nazareth-The Nazareth Hospital, Galilee Medical School-Bar-Ilan University (YN); Orthopedic Medicine, Medical Consulting Center, Nazareth Towers, General Medical Services "Sheruti Briut Clalit," Galilee Medical School-Bar-Ilan University (YA); Pediatric and Neonatal Department, EMMS Nazareth-The Nazareth Hospital, Galilee Medical School, Galilee Medical School-Bar-Ilan University (AA); and Clinical Neuroscience, Neuropsychopharmacology & Population Genetics, Research Center, EMMS Hospital, Nazareth-The Nazareth Hospital (AB), Israel
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11
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Lupi F, Bozzola M, Longhi S, Farello G, Radetti G. The effect of two different GH dosages on final height and bone geometry. Ital J Pediatr 2016; 42:5. [PMID: 26769291 PMCID: PMC4714449 DOI: 10.1186/s13052-016-0212-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 01/04/2016] [Indexed: 11/21/2022] Open
Abstract
Background Growth hormone (GH) has a strong positive influence on bone, stimulating both bone elongation and increase in size. The aim of the study was to compare the effect of two different GH dosages on final height and bone geometry in two groups of GH-deficient children. Methods We evaluated 121 children (86 m, 35f). Group 1 (77 patients) treated with GH at a mean dose of 0.16 mg/kg/week and group 2 (44 patients) at 0.3 mg/kg/week. Bone geometry was evaluated at final height from a digitalized X-ray of the left hand considering the following parameters: metacarpal index (MI), cross-sectional area (CSA), cortical area (CA) and medullary area (MA). Results At baseline, group 2 was shorter than group 1 (−1.54 vs −1.01 SDS; p < 0.005), while at final height there was no difference. Height gain was significantly greater in group 2 than in group 1 (1.62 vs 1.13 SDS; p < 0.001). Bone geometry: MI was significantly greater in group 2 (0.62 vs 0.55; p < 0.001) as well as CA (46.87 vs 42.69 cm2; p < 0.005), while MA was significantly lower in group 2 (8.48 vs 11.65 cm2; p < 0.002). Conclusion Higher GH doses elicit a significantly greater statural gain and a greater bone cortical area.
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Affiliation(s)
- Fiorenzo Lupi
- Department of Paediatrics, Regional Hospital, via Lorenz Boehler 5, Bolzano, 39100, Italy.
| | - Mauro Bozzola
- Internal Medicine and Therapeutics Department, Pediatrics and Adolescentology Unit, University of Pavia, Fondazione IRCCS San Matteo, Viale Golgi 19, Pavia, 27100, Italy.
| | - Silvia Longhi
- Department of Paediatrics, Regional Hospital, via Lorenz Boehler 5, Bolzano, 39100, Italy.
| | - Giovanni Farello
- Life Health and Environmental Sciences Department, Pediatrics Unit, University of L'Aquila, via Vetoio Coppito, L'Aquila, 67100, Italy.
| | - Giorgio Radetti
- Marienklinik, via Claudia De Medici 2, Bolzano, 39100, Italy.
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12
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Juanes M, Guercio G, Marino R, Berensztein E, Warman DM, Ciaccio M, Gil S, Bailez M, Rivarola MA, Belgorosky A. Three novel IGF1R mutations in microcephalic patients with prenatal and postnatal growth impairment. Clin Endocrinol (Oxf) 2015; 82:704-11. [PMID: 25040157 DOI: 10.1111/cen.12555] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 06/09/2014] [Accepted: 07/11/2014] [Indexed: 12/01/2022]
Abstract
BACKGROUND IGF1R gene mutations have been associated with varying degrees of intrauterine and postnatal growth retardation, and microcephaly. OBJECTIVE To identify and characterize IGF1R gene variations in a cohort of 28 Argentinean children suspected of having IGF-1 insensitivity, who were selected on the basis of the association of pre/postnatal growth failure and microcephaly. METHODS The coding sequence and flanking intronic regions of IGF1R gene were amplified and directly sequenced. Functional characterization was performed by two in vitro assays: 1) [Methyl-(3) H] thymidine incorporation into DNA in fibroblast cell primary cultures from patients and controls treated with IGF-1 for 16-24 h. 2) PI3K/Akt pathway was evaluated with phospho-Akt (Ser473) STAR ELISA Kit (Millipore) in fibroblast cultures from patients and controls stimulated with IGF-1 for 10 min. Prepubertal clinical and GH-IGF-1 axis evaluation was followed up. RESULTS We identified three novel heterozygous missense mutations in three unrelated patients, de novo p.Arg1256Ser, de novo p.Asn359Tyr and p.Tyr865Cys. In control cells, proliferation assay showed that IGF-1 significantly induced DNA synthesis at 20 h and Akt phosphorylation assay that it significantly stimulated phosphorylation after 10 min (P < 0·05 by anova and Bonferroni Tests). However, no significant increase was observed in any of the three patient fibroblasts in both functional studies. GH therapy growth response in two patients was inconsistent. CONCLUSION These variations led to failure of the IGF1R function causing pre- and postnatal growth retardation and microcephaly. Microcephaly should be considered in the evaluation of SGA patients, because it seems to favour the frequency of detection of IGF1R mutations.
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Affiliation(s)
- Matias Juanes
- Endocrinology Service, Hospital de Pediatría Garrahan, Buenos Aires, Argentina
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13
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Longhi S, Grugni G, Gatti D, Spinozzi E, Sartorio A, Adami S, Fanolla A, Radetti G. Adults with Prader-Willi syndrome have weaker bones: effect of treatment with GH and sex steroids. Calcif Tissue Int 2015; 96:160-6. [PMID: 25577526 DOI: 10.1007/s00223-014-9949-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2014] [Accepted: 12/23/2014] [Indexed: 11/25/2022]
Abstract
Obesity has been considered to have a protective effect against the risk of fractures in adults. However, a high frequency of fracture is described in obese adults with Prader-Willi syndrome. To evaluate bone geometry, density and strength in a group of adult obese patients with Prader-Willi syndrome (PWS) and to examine the modulating effect on bone of treatment with growth hormone (GH) and sex steroids. This was a cross-sectional study performed in 41 (17 males, 24 females) obese subjects with genetically confirmed PWS, aged 29.4 ± 8.6 years. Forty-six healthy subjects (22 males and 24 females) served as controls. Digitalized X-rays were evaluated at the level of the 2nd metacarpal bone to assess bone geometry, i.e. cross-sectional area (CSA), cortical area (CA), medullary area (MA), metacarpal index (MI) and bone strength evaluated as bending breaking resistance index (BBRI). DEXA was also used to evaluate body composition and bone mineral density (total body, lumbar spine and femoral neck). PWS subjects, after adjusting for height and bone size, had a reduced CSA, CA and BBRI, while bone density was not different. GH treatment had a positive effect and sex steroids a negative effect on bone size and strength. PWS subjects showed a reduced bone size at the metacarpus leading to a reduced strength, while bone density was appropriate for size. GH treatment improves bone geometry but not bone density. Bone strength was significantly reduced in PWS patients who did not receive GH and had been treated with sex steroids.
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Affiliation(s)
- Silvia Longhi
- Department of Paediatrics, Regional Hospital Bolzano, L. Boehler 5, 39100, Bolzano, Italy
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14
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Interplay of proliferation and proapoptotic and antiapoptotic factors is revealed in the early human inner ear development. Otol Neurotol 2014; 35:695-703. [PMID: 24622024 DOI: 10.1097/mao.0000000000000210] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
HYPOTHESIS Spatiotemporal interplay of factors controlling proliferation, differentiation and apoptosis within the developing human inner ear is essential for labyrinth morphogenesis and development of vestibular and cochlear functions. BACKGROUND Studies on the early human inner ear development are scarce and insufficient. METHODS The immunolocalization of Ki-67, Bcl-2, caspase-3, and IGF-1 was analyzed in 6 human inner ears, 5 to 10 gestational weeks old. Statistical data were analyzed using the Kruskal-Wallis test. RESULTS During the analyzed period, the otocyst has transformed into cochlear duct and saccule ventrally and semicircular canals and utricle dorsally. Initial differentiation of sensorineural fields characterized organ of Corti, maculae, and cristae ampullares. Intense (50%) and evenly distributed proliferation Ki-67 in the otocyst decreased to 24% to 30% and became spatially restricted within the membranous labyrinth epithelium. Simultaneously, expression of antiapoptotic Bcl-2 protein increased in sensorineural fields of organ of Corti, macula, and crista ampullaris. Throughout the investigated period, apoptotic caspase-3 positive cells were mainly distributed at the luminal and basal surfaces of labyrinth epithelium. An inhibitor of apoptosis IGF-1 co-expressed with Bcl-2 and increased in the sensorineural fields with advancing development. CONCLUSION The described expression pattern indicates roles for cell proliferation in the growth of the inner ear and Bcl-2 in differentiation of sensorineural fields and protection from apoptosis. Both IGF-1-and caspase-3-mediated apoptosis seem to contribute to proper morphogenesis, differentiation, and innervations of sensorineural fields within the cochlea, semicircular canals, saccule, and utricle. Alterations in spatiotemporal interplay of investigated factors might lead to disturbances of vestibular and cochlear function.
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Sensational placodes: neurogenesis in the otic and olfactory systems. Dev Biol 2014; 389:50-67. [PMID: 24508480 PMCID: PMC3988839 DOI: 10.1016/j.ydbio.2014.01.023] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 01/27/2014] [Accepted: 01/28/2014] [Indexed: 11/22/2022]
Abstract
For both the intricate morphogenetic layout of the sensory cells in the ear and the elegantly radial arrangement of the sensory neurons in the nose, numerous signaling molecules and genetic determinants are required in concert to generate these specialized neuronal populations that help connect us to our environment. In this review, we outline many of the proteins and pathways that play essential roles in the differentiation of otic and olfactory neurons and their integration into their non-neuronal support structures. In both cases, well-known signaling pathways together with region-specific factors transform thickened ectodermal placodes into complex sense organs containing numerous, diverse neuronal subtypes. Olfactory and otic placodes, in combination with migratory neural crest stem cells, generate highly specialized subtypes of neuronal cells that sense sound, position and movement in space, odors and pheromones throughout our lives.
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Shi J, Tong JH, Cai S. GH1 T1663A polymorphism and cancer risk: a meta-analysis of case–control studies. Tumour Biol 2014; 35:4529-38. [DOI: 10.1007/s13277-013-1596-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 12/23/2013] [Indexed: 01/01/2023] Open
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17
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Clayton P, Bonnemaire M, Dutailly P, Maisonobe P, Naudin L, Pham E, Zhang Z, Grupe A, Thiagalingam A, Denèfle P. Characterizing short stature by insulin-like growth factor axis status and genetic associations: results from the prospective, cross-sectional, epidemiogenetic EPIGROW study. J Clin Endocrinol Metab 2013; 98:E1122-30. [PMID: 23596138 DOI: 10.1210/jc.2012-4283] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Serum IGF-I levels are often low in patients with short stature (SS) without defined etiology. Hence, genetic investigations have focused on the GH-IGF-I axis. OBJECTIVE Our objectives were to characterize IGF-I axis status and search for a broader range of genetic associations in children with SS and normal GH. DESIGN AND SETTING We conducted a prospective, cross-sectional, epidemiogenetic case-control study in 9 European countries (2008-2010). PARTICIPANTS Children (n = 275) aged ≥2 years with SS without defined etiology (≤-2.5 height SD score [SDS]) and ≥1 peak GH ≥7 μg/L) were recruited. METHODS Serum IGF-I, IGF-binding protein-3 (IGFBP-3), and acid-labile subunit (ALS) levels were measured in a central laboratory. Candidate gene exome sequencing was performed in this cohort and ethnicity-matched controls. RESULTS Serum IGF-I, IGFBP-3, and ALS levels were highly correlated, but there was a discrepancy between prevalence of IGF-I, IGFBP-3, and ALS deficiencies (53%, 30%, and 0.8%, respectively). An insertion-deletion (Indel) on the IGF1 gene (P = 1.2 × 10(-5), Bonferroni-corrected; case vs control frequency: 0.04 vs 0.112), an Indel on NFKB1 (P = 1.36 × 10(-10); case vs control frequency: 0.464 vs 0.272), and 2 single-nucleotide polymorphisms on ZBTB38 (P < 2.3 × 10(-6)) were associated with SS. At P < 10(-4), single-nucleotide polymorphisms on genes related to protein kinase regulation, MAPK, and Fanconi pathways were also associated with SS. CONCLUSIONS IGF-I deficiency is a common feature in SS without defined etiology; an Indel in the IGF1 gene was associated with SS. However, genes involved in transcriptional regulation (NFKB1 and ZBTB38) and growth factor signaling were also associated, providing further candidates for genetic investigations on individual patients.
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Affiliation(s)
- Peter Clayton
- University of Manchester, Manchester Academic Health Sciences Centre, Pediatric Endocrinology, Fifth Floor (Research), Royal Manchester Children's Hospital, Oxford Road, Manchester M13 9WL, United Kingdom.
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Padilla S, Orive G, Sánchez M, Anitua E, Wasterlain AS, Dragoo JL. Causality in biology has to answer 2 main questions--which and how: letter to the editor. Am J Sports Med 2013; 41:NP22-3. [PMID: 23636556 DOI: 10.1177/0363546513485062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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19
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Nakasato M, Kohsaka H, Mizutani T, Watanabe G, Taya K, Nagaoka K. Pregnancy-associated plasma protein (PAPP)-A expressed in the mammary gland controls epithelial cell proliferation and differentiation. Endocrine 2013; 43:387-93. [PMID: 22899098 DOI: 10.1007/s12020-012-9766-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 07/24/2012] [Indexed: 12/15/2022]
Abstract
Lactation is an important event in all-mammalian species. To investigate the role of pregnancy-associated plasma protein (PAPP)-A in lactogenesis, we determined (i) PAPP-A expression in mouse mammary glands and (ii) the biological functions of PAPP-A in mammary epithelial cells. PAPP-A mRNA level was low during early mid pregnancy and increased during mid-late pregnancy, and then slightly decreased during lactation. Cell proliferation signals, but not differentiation, increased PAPP-A mRNA expression in HC11 mammary epithelial cells. Treatment of recombinant PAPP-A protein stimulated HC11 cell proliferation and suppressed the expression of β-casein mRNA, which is one of the milk proteins and cell differentiation marker. Surprisingly, in forcing expression experiment, PAPP-A increased β-casein mRNA expression. Our data suggest that PAPP-A has different roles on intracellular expressing and extracellular treatment to mammary epithelial cells. Taken together, in early pregnancy, circulating PAPP-A protein might be supplied from other organs and stimulates mammary gland growth. In contrast, during mid-late pregnancy, local PAPP-A expression begins and enhances cell differentiation within mammary epithelial cell.
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Affiliation(s)
- Makoto Nakasato
- Department of Medicine and Rheumatology, and Global Center of Excellence Program, International Research Center for Molecular Science in Tooth and Bone Disease, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
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20
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Labarta JI, Barrio E, Audí L, Fernández-Cancio M, Andaluz P, de Arriba A, Puga B, Calvo MT, Mayayo E, Carrascosa A, Ferrández-Longás A. Familial short stature and intrauterine growth retardation associated with a novel mutation in the IGF-I receptor (IGF1R) gene. Clin Endocrinol (Oxf) 2013; 78:255-62. [PMID: 22738321 DOI: 10.1111/j.1365-2265.2012.04481.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Revised: 05/15/2012] [Accepted: 06/21/2012] [Indexed: 11/27/2022]
Abstract
CONTEXT IGF-I is essential for normal human growth and mediates its effects through the IGF1R. IGF1R mutations have been associated with varying degrees of intrauterine and postnatal growth retardation. OBJECTIVE To identify IGF1R gene mutations in a short-statured family with intrauterine growth retardation and microcephaly. METHODS Direct DNA sequencing was used to identify IGF1R mutations. Multiplex ligation-dependent probe amplification analyses were performed for deletions and duplications of all IGF1R exons. Functional studies were conducted to assess mutation pathogenicity. RESULTS A novel heterozygous IGF1R missense mutation in exon 7 (c.A1549T, p.Y487F) was identified in a short-statured girl with severe prenatal growth retardation and microcephaly. The same mutation was also identified in her mother, who presented prenatal and postnatal growth failure, and her short-statured maternal grandmother, both of whom exhibited microcephaly. The index case showed a partial response to rhGH. Functional studies performed in dermal fibroblasts from the index case and her mother showed normal IGF-I binding; however, IGF-I activation of intracellular signalling measured as AKT and extracellular signal-regulated kinase phosphorylation was markedly reduced, with patients' values being lower than those of her mother. IGF-I stimulation of DNA synthesis was significantly reduced compared with controls. CONCLUSION Our results show a novel missense mutation in the IGF1R gene (c.A1549T, p.Y487F) associated with prenatal and postnatal growth failure and microcephaly in the context of familial short stature. The functional studies are in line with the inactivation of one copy of the IGF1R gene with variable expression within the same family.
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Affiliation(s)
- José I Labarta
- Endocrinology Unit, Department of Pediatrics, Hospital Infantil Universitario Miguel Servet, Zaragoza, Spain.
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21
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Wasterlain AS, Braun HJ, Harris AHS, Kim HJ, Dragoo JL. The systemic effects of platelet-rich plasma injection. Am J Sports Med 2013; 41:186-93. [PMID: 23211708 DOI: 10.1177/0363546512466383] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Platelet-rich plasma (PRP) is an autologous blood product used to treat acute and chronic tendon, ligament, and muscle injuries in over 86,000 athletes in the United States annually. The World Anti-Doping Agency (WADA) banned intramuscular PRP injections in competitive athletes in 2010 because of concerns that it may increase performance-enhancing growth factors. The ban on PRP was removed in 2011 because of limited evidence for a systemic ergogenic effect of PRP, but the growth factors within PRP remain prohibited. PURPOSE To quantify the effect of PRP injection on systemic growth factors with performance-enhancing effects and to identify molecular markers to detect treated athletes. STUDY DESIGN Descriptive laboratory study. METHODS Six ergogenic growth factors monitored by WADA-human growth hormone (hGH), insulin-like growth factor-1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3), basic fibroblast growth factor (bFGF or FGF-2), vascular endothelial growth factor (VEGF), and platelet-derived growth factor-BB (PDGF-BB)-were measured in 25 patients before (baseline) and at 0.25, 3, 24, 48, 72, and 96 hours after intratendinous leukocyte-rich PRP injection. Eating and exercise were prohibited for 3 hours before testing. Growth factors were quantified by enzyme-linked immunosorbent assay, and the change relative to each patient's baseline was calculated. RESULTS Relative to serum, PRP contained significantly more bFGF (226 vs 5 pg/mL), VEGF (1426 vs 236 pg/mL), and PDGF-BB (26,285 vs 392 pg/mL), but IGF-1 and hGH were not elevated. Serum levels increased significantly for IGF-1 at 24 and 48 hours, for bFGF at 72 and 96 hours, and for VEGF at 3, 24, 48, 72, and 96 hours after PRP injection. Additionally, VEGF was increased in all 25 patients after PRP treatment. CONCLUSION Serum IGF-1, VEGF, and bFGF levels are significantly elevated after PRP injection, supporting a possible ergogenic effect of PRP. An indirect marker for hGH doping, the product of IGFBP-3 × IGF-1, also significantly increased after PRP. Platelet-rich plasma appears to trigger an increase in circulating growth factors through activating biological pathways rather than by serving as a vehicle for the direct delivery of presynthesized growth factors. Elevated VEGF was observed in all patients after PRP, and ≥88% of patients had elevated VEGF at each time point from 3 to 96 hours after PRP, suggesting that VEGF may be a sensitive molecular marker to detect athletes recently treated with PRP. CLINICAL RELEVANCE This is the first and only adequately powered study of the systemic effects of PRP. We present evidence that PRP contains and may trigger systemic increases in substances currently banned in competitive athletes. Finally, we provide evidence that VEGF could serve as a useful molecular marker to detect athletes treated with PRP.
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Affiliation(s)
- Amy S Wasterlain
- Department of Orthopaedic Surgery, Stanford University, California, USA
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Du Y, Liu B, Guo F, Xu G, Ding Y, Liu Y, Sun X, Xu G. The essential role of Mbd5 in the regulation of somatic growth and glucose homeostasis in mice. PLoS One 2012; 7:e47358. [PMID: 23077600 PMCID: PMC3471830 DOI: 10.1371/journal.pone.0047358] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Accepted: 09/11/2012] [Indexed: 12/16/2022] Open
Abstract
Methyl-CpG binding domain protein 5 (MBD5) belongs to the MBD family proteins, which play central roles in transcriptional regulation and development. The significance of MBD5 function is highlighted by recent studies implicating it as a candidate gene involved in human 2q23.1 microdeletion syndrome. To investigate the physiological role of Mbd5, we generated knockout mice. The Mbd5-deficient mice showed growth retardation, wasting and pre-weaning lethality. The observed growth retardation was associated with the impairment of GH/IGF-1 axis in Mbd5-null pups. Conditional knockout of Mbd5 in the brain resulted in the similar phenotypes as whole body deletion, indicating that Mbd5 functions in the nervous system to regulate postnatal growth. Moreover, the mutant mice also displayed enhanced glucose tolerance and elevated insulin sensitivity as a result of increased insulin signaling, ultimately resulting in disturbed glucose homeostasis and hypoglycemia. These results indicate Mbd5 as an essential factor for mouse postnatal growth and maintenance of glucose homeostasis.
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Affiliation(s)
- Yarui Du
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Bo Liu
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Fan Guo
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Guifang Xu
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Yuqiang Ding
- Tongji University School of Medicine, Shanghai, People’s Republic of China
| | - Yong Liu
- Institute of Nutrition Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
| | - Xin Sun
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Guoliang Xu
- The State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, People’s Republic of China
- * E-mail:
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Abstract
The importance of the insulin-like growth factor (IGF)-I axis in the regulation of bone size and bone mineral density, two important determinants of bone strength, has been well established from clinical studies involving patients with growth hormone deficiency and IGF-I gene disruption. Data from transgenic animal studies involving disruption and overexpression of components of the IGF-I axis also provide support for a key role for IGF-I in bone metabolism. IGF-I actions in bone are subject to regulation by systemic hormones, local growth factors, as well as mechanical stress. In this review we describe findings from various genetic mouse models that pertain to the role of endocrine and local sources of IGF-I in the regulation of skeletal growth.
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Affiliation(s)
- Subburaman Mohan
- Musculoskeletal Disease Center, Research Service (151), Jerry L Pettis VA Medical Center, 11201 Benton Street, Loma Linda, CA, 92357, USA.
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Age-related functional and structural retinal modifications in the Igf1−/− null mouse. Neurobiol Dis 2012; 46:476-85. [DOI: 10.1016/j.nbd.2012.02.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Revised: 02/06/2012] [Accepted: 02/20/2012] [Indexed: 02/05/2023] Open
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Xing W, Govoni KE, Donahue LR, Kesavan C, Wergedal J, Long C, Bassett JHD, Gogakos A, Wojcicka A, Williams GR, Mohan S. Genetic evidence that thyroid hormone is indispensable for prepubertal insulin-like growth factor-I expression and bone acquisition in mice. J Bone Miner Res 2012; 27:1067-79. [PMID: 22513648 PMCID: PMC3399953 DOI: 10.1002/jbmr.1551] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Understanding how bone growth is regulated by hormonal and mechanical factors during early growth periods is important for optimizing the attainment of peak bone mass to prevent or postpone the occurrence of fragility fractures later in life. Using genetic mouse models that are deficient in thyroid hormone (TH) (Tshr(-/-) and Duox2(-/-)), growth hormone (GH) (Ghrhr(lit/lit)), or both (Tshr(-/-); Ghrhr(lit/lit)), we demonstrate that there is an important period prior to puberty when the effects of GH are surprisingly small and TH plays a critical role in the regulation of skeletal growth. Daily administration of T3/T4 during days 5 to 14, the time when serum levels of T3 increase rapidly in mice, rescued the skeletal deficit in TH-deficient mice but not in mice lacking both TH and GH. However, treatment of double-mutant mice with both GH and T3/T4 rescued the bone density deficit. Increased body fat in the TH-deficient as well as TH/GH double-mutant mice was rescued by T3/T4 treatment during days 5 to 14. In vitro studies in osteoblasts revealed that T3 in the presence of TH receptor (TR) α1 bound to a TH response element in intron 1 of the IGF-I gene to stimulate transcription. In vivo studies using TRα and TRβ knockout mice revealed evidence for differential regulation of insulin-like growth factor (IGF)-I expression by the two receptors. Furthermore, blockade of IGF-I action partially inhibited the biological effects of TH, thus suggesting that both IGF-I-dependent and IGF-I-independent mechanisms contribute to TH effects on prepubertal bone acquisition.
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Affiliation(s)
- Weirong Xing
- Musculoskeletal Disease Center, Loma Linda VA HealthCare System, Loma Linda, CA 92357, USA
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Tran PV, Fretham SJB, Wobken J, Miller BS, Georgieff MK. Gestational-neonatal iron deficiency suppresses and iron treatment reactivates IGF signaling in developing rat hippocampus. Am J Physiol Endocrinol Metab 2012; 302:E316-24. [PMID: 22068601 PMCID: PMC3287363 DOI: 10.1152/ajpendo.00369.2011] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Gestational-neonatal iron deficiency, a common micronutrient deficiency affecting the offspring of more than 30% of pregnancies worldwide, leads to long-term cognitive and behavioral abnormalities. Preclinical models of gestational-neonatal iron deficiency result in reduced energy metabolism and expression of genes critical for neuronal plasticity and cognitive function, which are associated with a smaller hippocampal volume and abnormal neuronal dendrite growth. Because insulin-like growth factor (IGF) modulates early postnatal cellular growth, differentiation, and survival, we used a dietary-induced rat model to assess the effects of gestational iron deficiency on activity of the IGF system. We hypothesized that gestational iron deficiency attenuates postnatal hippocampal IGF signaling and results in downstream effects that contribute to hippocampal anatomic and functional deficits. At postnatal day (P) 15 untreated gestational-neonatal iron deficiency markedly suppressed hippocampal IGF activation and protein kinase B signaling, and reduced neurogenesis, while elevating extracellular signal-regulated kinase 1/2 signaling and hypoxia-inducible factor-1α expression. Iron treatment beginning at P7 restored IGF signaling, increased neurogenesis, and normalized all parameters by the end of rapid hippocampal differentiation (P30). Expression of the neuron-specific synaptogenesis marker, disc-large homolog 4 (PSD95), increased more rapidly than the glia-specific myelination marker, myelin basic protein, following iron treatment, suggesting a more robust response to iron therapy in IGF-I-dependent neurons than IGF-II-dependent glia. Collectively, our findings suggest that IGF dysfunction is in part responsible for hippocampal abnormalities in untreated iron deficiency. Early postnatal iron treatment of gestational iron deficiency reactivates the IGF system and promotes neurogenesis and differentiation in the hippocampus during a critical developmental period.
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MESH Headings
- Anemia, Iron-Deficiency/diet therapy
- Anemia, Iron-Deficiency/metabolism
- Anemia, Iron-Deficiency/pathology
- Animals
- Female
- Gene Expression Regulation, Developmental
- Hippocampus/metabolism
- Hippocampus/pathology
- Insulin-Like Growth Factor Binding Protein 3/genetics
- Insulin-Like Growth Factor Binding Protein 3/metabolism
- Insulin-Like Growth Factor I/genetics
- Insulin-Like Growth Factor I/metabolism
- Insulin-Like Growth Factor II/genetics
- Insulin-Like Growth Factor II/metabolism
- Iron, Dietary/administration & dosage
- Iron, Dietary/therapeutic use
- Lactation
- Male
- Maternal Nutritional Physiological Phenomena
- Neurogenesis
- Neurons/metabolism
- Pregnancy
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, IGF Type 1/genetics
- Receptor, IGF Type 1/metabolism
- Receptor, Insulin/genetics
- Receptor, Insulin/metabolism
- Signal Transduction
- Somatomedins/genetics
- Somatomedins/metabolism
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Affiliation(s)
- Phu V Tran
- Center for Neurobehavioral Development, University of Minnesota, Minneapolis MN, USA.
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Bush JR, Wevrick R. Loss of the Prader-Willi obesity syndrome protein necdin promotes adipogenesis. Gene 2012; 497:45-51. [PMID: 22305984 DOI: 10.1016/j.gene.2012.01.027] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 01/19/2012] [Indexed: 01/07/2023]
Abstract
We investigated the role of necdin during adipogenic differentiation. Necdin is one of several genes inactivated in children with Prader-Willi syndrome, who are predisposed to increased adiposity at the expense of lean mass. Necdin promotes neuronal and muscle differentiation and survival through interactions with a variety of proteins, including cell surface receptors, modifiers of protein stability, and transcription factors. In pre-adipocytes, necdin over-expression inhibits adipogenesis, while reducing necdin levels enhances adipogenic differentiation in tissue culture cells. We now directly demonstrate a role for necdin in inhibiting adipogenesis using cells derived from necdin deficient mice.
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Affiliation(s)
- Jason Russell Bush
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
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28
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Aburto MR, Magariños M, Leon Y, Varela-Nieto I, Sanchez-Calderon H. AKT signaling mediates IGF-I survival actions on otic neural progenitors. PLoS One 2012; 7:e30790. [PMID: 22292041 PMCID: PMC3264639 DOI: 10.1371/journal.pone.0030790] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 12/29/2011] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Otic neurons and sensory cells derive from common progenitors whose transition into mature cells requires the coordination of cell survival, proliferation and differentiation programmes. Neurotrophic support and survival of post-mitotic otic neurons have been intensively studied, but the bases underlying the regulation of programmed cell death in immature proliferative otic neuroblasts remains poorly understood. The protein kinase AKT acts as a node, playing a critical role in controlling cell survival and cell cycle progression. AKT is activated by trophic factors, including insulin-like growth factor I (IGF-I), through the generation of the lipidic second messenger phosphatidylinositol 3-phosphate by phosphatidylinositol 3-kinase (PI3K). Here we have investigated the role of IGF-dependent activation of the PI3K-AKT pathway in maintenance of otic neuroblasts. METHODOLOGY/PRINCIPAL FINDINGS By using a combination of organotypic cultures of chicken (Gallus gallus) otic vesicles and acoustic-vestibular ganglia, Western blotting, immunohistochemistry and in situ hybridization, we show that IGF-I-activation of AKT protects neural progenitors from programmed cell death. IGF-I maintains otic neuroblasts in an undifferentiated and proliferative state, which is characterised by the upregulation of the forkhead box M1 (FoxM1) transcription factor. By contrast, our results indicate that post-mitotic p27(Kip)-positive neurons become IGF-I independent as they extend their neuronal processes. Neurons gradually reduce their expression of the Igf1r, while they increase that of the neurotrophin receptor, TrkC. CONCLUSIONS/SIGNIFICANCE Proliferative otic neuroblasts are dependent on the activation of the PI3K-AKT pathway by IGF-I for survival during the otic neuronal progenitor phase of early inner ear development.
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Affiliation(s)
- Maria R Aburto
- Instituto de Investigaciones Biomedicas Alberto Sols, CSIC-UAM, Madrid, Spain
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29
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Murillo-Cuesta S, Rodríguez-de la Rosa L, Cediel R, Lassaletta L, Varela-Nieto I. The role of insulin-like growth factor-I in the physiopathology of hearing. Front Mol Neurosci 2011; 4:11. [PMID: 21845174 PMCID: PMC3146045 DOI: 10.3389/fnmol.2011.00011] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Accepted: 07/11/2011] [Indexed: 01/19/2023] Open
Abstract
Insulin-like growth factor-I (IGF-I) belongs to the family of polypeptides of insulin, which play a central role in embryonic development and adult nervous system homeostasis by endocrine, autocrine, and paracrine mechanisms. IGF-I is fundamental for the regulation of cochlear development, growth, and differentiation, and its mutations are associated with hearing loss in mice and men. Low levels of IGF-I have been shown to correlate with different human syndromes showing hearing loss and with presbyacusis. Animal models are fundamental to understand the genetic, epigenetic, and environmental factors that contribute to human hearing loss. In the mouse, IGF-I serum levels decrease with aging and there is a concomitant hearing loss and retinal degeneration. In the Igf1(-/-) null mouse, hearing loss is due to neuronal loss, poor innervation of the sensory hair cells, and age-related stria vascularis alterations. In the inner ear, IGF-I actions are mediated by intracellular signaling networks, RAF, AKT, and p38 MAPK protein kinases modulate the expression and activity of transcription factors, as AP1, MEF2, FoxM1, and FoxP3, leading to the regulation of cell cycle and metabolism. Therapy with rhIGF-I has been approved in humans for the treatment of poor linear growth and certain neurodegenerative diseases. This review will discuss these findings and their implications in new IGF-I-based treatments for the protection or repair of hearing loss.
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Affiliation(s)
- Silvia Murillo-Cuesta
- Servicio de Evaluación Neurofuncional no Invasiva, Instituto de Investigaciones Biomédicas Alberto Sols, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid Madrid, Spain
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30
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Luna-Nevarez P, Rincon G, Medrano JF, Riley DG, Chase CC, Coleman SW, VanLeeuwen DM, DeAtley KL, Islas-Trejo A, Silver GA, Thomas MG. Single nucleotide polymorphisms in the growth hormone–insulin-like growth factor axis in straightbred and crossbred Angus, Brahman, and Romosinuano heifers: Population genetic analyses and association of genotypes with reproductive phenotypes1. J Anim Sci 2011; 89:926-34. [DOI: 10.2527/jas.2010-3483] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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31
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Genetic defects causing functional and structural isolated growth hormone deficiency. Transl Neurosci 2011. [DOI: 10.2478/s13380-011-0013-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractNormal somatic growth requires the integrated function of many of the hormonal, metabolic, and other growth factors involved in the hypothalamo-pituitary-somatotrope axis. Human growth hormone (hGH) causes a variety of physiological and metabolic effects in humans and its pivotal role in postnatal growth is undisputed. Disturbances that occur during this process often cause subnormal GH secretion and/or subnormal GH sensitivity/responsiveness resulting in short stature. Despite the complexity of this linear growth process, the growth pattern of children, if evaluated in the context of normal standards, is rather predictable. Children presenting with short stature (i.e out of normal standards) are treated with daily injections of recombinant human GH (rhGH), which leads in almost all cases to an increase of height velocity. Although it is becoming more and more evident that many genes are involved in controlling the regulation of growth, the main aim of this review is to focus on the GH-1 gene, the various gene alterations and their important physiological and pathophysiological role in growth.
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Bowman CJ, Streck RD, Chapin RE. Maternal-placental insulin-like growth factor (IGF) signaling and its importance to normal embryo-fetal development. ACTA ACUST UNITED AC 2010; 89:339-49. [PMID: 20803692 DOI: 10.1002/bdrb.20249] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
As background for an antibody-based therapeutic program against the IGF receptor, we undertook a review of available information on the early pregnancy-specific regulation and localization of IGFs, IGF-binding proteins (BPs), IGFBP-specific proteases, and the type 1 IGF receptor relative to placental maintenance, function of placental nutrient transporters, placental cellular differentiation/turnover/apoptosis, and critical hormone signaling needed to maintain pregnancy. Possible adverse outcomes of altered IGF signaling include prenatal loss, fetal growth retardation, and maldevelopment are also discussed. It appears that the IGF axes in both the conceptus and mother are important for normal embryo-fetal growth. Thus, all molecules (i.e., both small and large) that disrupt the IGF axis could be expected to have some degree of fetal consequences.
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Affiliation(s)
- Christopher J Bowman
- Drug Safety Research and Development, Pfizer, Inc, Groton, Connecticut 06340, USA.
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33
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Cody JD, Heard P, Hale D. Identification of two novel chromosome regions associated with isolated growth hormone deficiency. J Pediatr Endocrinol Metab 2010; 23:1159-64. [PMID: 21284329 DOI: 10.1515/jpem.2010.181] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The goal of this study was to identify novel candidate genes that may cause or predispose to growth hormone (GH) deficiency. DNA samples from 45 individuals with isolated GH deficiency were assessed using oligonucleotide microarray comparative genomic hybridization. Five individuals with previously unreported copy number variants were identified. Two of the five individuals were hemizygous for regions already known to cause GH deficiency (chromosomes 22q11.21 and 15q26.3). The remaining three individuals had copy number changes involving two novel chromosome regions. One individual had a homozygous deletion of a 2.2 Mb region of 13q33.1 that contains a single gene: integrin, beta-like 1 (ITGBL1). The remaining two individuals had duplications of 4.7 Mb on chromosome 20q13.13. This region includes eight genes not previously identified as copy number variants. These genes are ARFGEF2, CSE1L, DDX27, ZNFX1, C20orf199, SNORD12, KCNB1, and PTGIS. Thus, further investigations into these potential candidate genes are necessary.
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Affiliation(s)
- Jannine D Cody
- Department of Pediatrics, University of Texas Health Science Center at San Antonio, USA.
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34
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Riquelme R, Cediel R, Contreras J, la Rosa Lourdes RD, Murillo-Cuesta S, Hernandez-Sanchez C, Zubeldia JM, Cerdan S, Varela-Nieto I. A comparative study of age-related hearing loss in wild type and insulin-like growth factor I deficient mice. Front Neuroanat 2010; 4:27. [PMID: 20661454 PMCID: PMC2907134 DOI: 10.3389/fnana.2010.00027] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Accepted: 06/01/2010] [Indexed: 01/07/2023] Open
Abstract
Insulin-like growth factor-I (IGF-I) belongs to the family of insulin-related peptides that fulfils a key role during the late development of the nervous system. Human IGF1 mutations cause profound deafness, poor growth and mental retardation. Accordingly, Igf1−/− null mice are dwarfs that have low survival rates, cochlear alterations and severe sensorineural deafness. Presbycusis (age-related hearing loss) is a common disorder associated with aging that causes social and cognitive problems. Aging is also associated with a decrease in circulating IGF-I levels and this reduction has been related to cognitive and brain alterations, although there is no information as yet regarding the relationship between presbycusis and IGF-I biodisponibility. Here we present a longitudinal study of wild type Igf1+/+ and null Igf1−/− mice from 2 to 12 months of age comparing the temporal progression of several parameters: hearing, brain morphology, cochlear cytoarchitecture, insulin-related factors and IGF gene expression and IGF-I serum levels. Complementary invasive and non-invasive techniques were used, including auditory brainstem-evoked response (ABR) recordings and in vivo MRI brain imaging. Igf1−/− null mice presented profound deafness at all the ages studied, without any obvious worsening of hearing parameters with aging. Igf1+/+ wild type mice suffered significant age-related hearing loss, their auditory thresholds and peak I latencies augmenting as they aged, in parallel with a decrease in the circulating levels of IGF-I. Accordingly, there was an age-related spiral ganglion degeneration in wild type mice that was not evident in the Igf1 null mice. However, the Igf1−/− null mice in turn developed a prematurely aged stria vascularis reminiscent of the diabetic strial phenotype. Our data indicate that IGF-I is required for the correct development and maintenance of hearing, supporting the idea that IGF-I-based therapies could contribute to prevent or ameliorate age-related hearing loss.
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Affiliation(s)
- Raquel Riquelme
- Instituto de Investigaciones Biomedicas "Alberto Sols", CSIC-UAM Madrid, Spain
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35
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Bowman CJ, Chmielewski G, Oneda S, Finco D, Boucher MA, Todd M. Embryo-fetal developmental toxicity of figitumumab, an anti-insulin-like growth factor-1 receptor (IGF-1R) monoclonal antibody, in cynomolgus monkeys. ACTA ACUST UNITED AC 2010; 89:326-38. [DOI: 10.1002/bdrb.20248] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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36
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Escrivá F, González-Rodriguez Á, Fernández-Millán E, Rondinone CM, Álvarez C, Valverde ÁM. PTP1B deficiency enhances liver growth during suckling by increasing the expression of insulin-like growth factor-I. J Cell Physiol 2010; 225:214-22. [DOI: 10.1002/jcp.22246] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Backeljauw P, Bang P, Dunger DB, Juul A, Le Bouc Y, Rosenfeld R. Insulin-like growth factor-I in growth and metabolism. J Pediatr Endocrinol Metab 2010; 23:3-16. [PMID: 20432800 DOI: 10.1515/jpem.2010.23.1-2.3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Deficiency of insulin-like growth factor-I (IGF-I) results in growth failure. A variety of molecular defects have been found to underlie severe primary IGF-I deficiency (IGFD), in which serum IGF-I concentrations are substantially decreased and fail to respond to GH therapy. Identification of more patients with primary or secondary IGFD is likely with investigative and diagnostic progress, particularly in the assessment of children with idiopathic short stature. Diagnosis of IGFD requires accurate and reliable IGF-I assays, adequate normative data for reference, and knowledge of IGF-I physiology for proper interpretation of data. Recombinant human IGF-I (rhIGF-I) treatment improves stature in patients with severe primary IGFD, and has also been shown to improve glycaemic control and insulin sensitivity in patients with severe insulin resistance. Ongoing studies of patients receiving rhIGF-I will allow further evaluation of the clinical utility of this treatment, with concurrent increase in our understanding of IGF-I and conditions of IGFD.
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Affiliation(s)
- P Backeljauw
- Division of Pediatric Endocrinology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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38
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Dedoussis GV, Louizou E, Papoutsakis C, Skenderi KP, Yannakoulia M. Dairy intake associates with the IGF rs680 polymorphism to height variation in periadolescent children. Eur J Clin Nutr 2009; 64:253-8. [DOI: 10.1038/ejcn.2009.124] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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39
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Dunn GA, Bale TL. Maternal high-fat diet promotes body length increases and insulin insensitivity in second-generation mice. Endocrinology 2009; 150:4999-5009. [PMID: 19819967 PMCID: PMC2775990 DOI: 10.1210/en.2009-0500] [Citation(s) in RCA: 216] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Maternal obesity and diet consumption during pregnancy have been linked to offspring adiposity, cardiovascular disease, and impaired glucose metabolism. Furthermore, nutrition during development is clearly linked to somatic growth. However, few studies have examined whether phenotypes derived from maternal high-fat diet exposure can be passed to subsequent generations and by what mechanisms this may occur. Here we report the novel finding of a significant body length increase that persisted across at least two generations of offspring in response to maternal high-fat diet exposure. This phenotype is not attributable to altered intrauterine conditions or maternal feeding behavior because maternal and paternal lineages were able to transmit the effect, supporting a true epigenetic manner of inheritance. We also detected a heritable feature of reduced insulin sensitivity across two generations. Alterations in the GH secretagogue receptor (GHSR), the GHSR transcriptional repressor AF5q31, plasma IGF-I concentrations, and IGF-binding protein-3 (IGFBP3) suggest a contribution of the GH axis. These studies provide evidence that the heritability of body length and glucose homeostasis are modulated by maternal diet across multiple generations, providing a mechanism where length can increase rapidly in concert with caloric availability.
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Affiliation(s)
- Gregory A Dunn
- University of Pennsylvania, Department of Animal Biology, 201E Vet, 6046, 3800 Spruce Street, Philadelphia, Pennsylvania 19104-6046, USA
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40
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Netchine I, Azzi S, Houang M, Seurin D, Perin L, Ricort JM, Daubas C, Legay C, Mester J, Herich R, Godeau F, Le Bouc Y. Partial primary deficiency of insulin-like growth factor (IGF)-I activity associated with IGF1 mutation demonstrates its critical role in growth and brain development. J Clin Endocrinol Metab 2009; 94:3913-21. [PMID: 19773405 DOI: 10.1210/jc.2009-0452] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT IGF-I is essential for fetal and postnatal development. Only three IGF1 defects leading to dramatic loss of binding to its type 1 receptor, IGF-1R, have been reported. PATIENT We describe a very lean boy who has intrauterine growth restriction and progressive postnatal growth failure associated with normal hearing, microcephaly, and mild intellectual impairment. He had markedly reduced concentrations of IGF-I, with IGFBP-3 and ALS serum levels in the upper normal range or above. IGF-I serum concentrations differed according to the immunoassay used. A higher than average GH dose was required for catch-up growth. Given the mismatch between IGF-I and IGFBP-3 levels, we sequenced his IGF1 gene. RESULT We identified a homozygous missense IGF1 mutation. This causes the replacement of a highly conserved amino acid (arginine 36) by a glutamine (R36Q) in the C domain of the predicted peptide. We showed that the abnormal IGF-I peptide has reduced mitogenic activity and partial loss of binding to its receptor IGF-1R. The patient's IGF-I level was undetectable in a highly specific monoclonal assay but elevated in a polyclonal assay. CONCLUSION This first report of mild deficiency of IGF-I activity demonstrates that the integrity of IGF-I signaling is important for normal growth and brain development. Molecular defects leading to partial loss of IGF-I activity may not be uncommon in patients born small for gestational age. The characterization of this complex phenotype and identification of such molecular defects have therapeutic implications, particularly now that, in addition to GH, recombinant IGF-I is available for clinical use.
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Affiliation(s)
- Irène Netchine
- Assistance Publique-Hôpitaux de Paris, Hôpital Armand-Trousseau, Explorations Fonctionnelles Endocriniennes, 75012 Paris, France.
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41
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Ohlsson C, Mohan S, Sjögren K, Tivesten A, Isgaard J, Isaksson O, Jansson JO, Svensson J. The role of liver-derived insulin-like growth factor-I. Endocr Rev 2009; 30:494-535. [PMID: 19589948 PMCID: PMC2759708 DOI: 10.1210/er.2009-0010] [Citation(s) in RCA: 291] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
IGF-I is expressed in virtually every tissue of the body, but with much higher expression in the liver than in any other tissue. Studies using mice with liver-specific IGF-I knockout have demonstrated that liver-derived IGF-I, constituting a major part of circulating IGF-I, is an important endocrine factor involved in a variety of physiological and pathological processes. Detailed studies comparing the impact of liver-derived IGF-I and local bone-derived IGF-I demonstrate that both sources of IGF-I can stimulate longitudinal bone growth. We propose here that liver-derived circulating IGF-I and local bone-derived IGF-I to some extent have overlapping growth-promoting effects and might have the capacity to replace each other (= redundancy) in the maintenance of normal longitudinal bone growth. Importantly, and in contrast to the regulation of longitudinal bone growth, locally derived IGF-I cannot replace (= lack of redundancy) liver-derived IGF-I for the regulation of a large number of other parameters including GH secretion, cortical bone mass, kidney size, prostate size, peripheral vascular resistance, spatial memory, sodium retention, insulin sensitivity, liver size, sexually dimorphic liver functions, and progression of some tumors. It is clear that a major role of liver-derived IGF-I is to regulate GH secretion and that some, but not all, of the phenotypes in the liver-specific IGF-I knockout mice are indirect, mediated via the elevated GH levels. All of the described multiple endocrine effects of liver-derived IGF-I should be considered in the development of possible novel treatment strategies aimed at increasing or reducing endocrine IGF-I activity.
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Affiliation(s)
- Claes Ohlsson
- Division of Endocrinology, Institute of Medicine, Sahlgrenska University Hospital, Göteborg, Sweden.
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42
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Pass C, MacRae VE, Ahmed SF, Farquharson C. Inflammatory cytokines and the GH/IGF-I axis: novel actions on bone growth. Cell Biochem Funct 2009; 27:119-27. [PMID: 19330796 DOI: 10.1002/cbf.1551] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Longitudinal bone growth is a tightly regulated process that relies on complex synchronized mechanisms at the growth plate. Chronic paediatric inflammatory diseases are well accepted to lead to growth retardation and this is likely due to raised inflammatory cytokine levels and reduced growth hormone (GH)/insulin-like growth factor-1 (IGF-I) signalling. The precise cellular mechanisms responsible for this inhibition are unclear and therefore in this article, we will review the potential interactions between inflammatory cytokines and the GH/IGF-I axis in the regulation of bone growth. In particular, we will emphasis the potential contribution of the suppressors of cytokine signalling (SOCS) proteins, and in particular SOCS2, in mediating this process.
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Affiliation(s)
- C Pass
- The Roslin Institute and Royal School of Veterinary Studies, The University of Edinburgh, Midlothian, UK.
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43
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Nasonkin IO, Potok MA, Camper SA. Cre-mediated recombination in pituitary somatotropes. Genesis 2009; 47:55-60. [PMID: 19039787 DOI: 10.1002/dvg.20462] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We report a transgenic line with highly penetrant cre recombinase activity in the somatotrope cells of the anterior pituitary gland. Expression of the cre transgene is under the control of the locus control region of the human growth hormone gene cluster and the rat growth hormone promoter. Cre recombinase activity was assessed with two different lacZ reporter genes that require excision of a floxed stop sequence for expression: a chick beta-actin promoter with the CMV enhancer transgene and a ROSA26 knock-in. Cre activity is detectable in the developing pituitary after initiation of Gh transcription and persists through adulthood with high penetrance in Gh expressing cells and lower penetrance in lactotropes, a cell type that shares a common origin with somatotropes. This Gh-cre transgenic line is suitable for efficient, cell-specific deletion of floxed regions of genomic DNA in differentiated somatotropes and a subset of lactotrope cells of the anterior pituitary gland.
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Affiliation(s)
- Igor O Nasonkin
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109-5618, USA
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44
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Yamazaki M, Sato A, Nishio SI, Takeda T, Miyamoto T, Katai M, Hashizume K. Acromegaly accompanied by Turner syndrome with 47,XXX/45,X/46,XX mosaicism. Intern Med 2009; 48:447-53. [PMID: 19293545 DOI: 10.2169/internalmedicine.48.1157] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 33-year-old woman was hospitalized for examination of edematous laryngopharynx. She was acromegalic. A pituitary adenoma with elevated serum levels of growth hormone (GH) and insulin-like growth factor-I (IGF-I) was detected, indicating acromegaly caused by GH-secreting pituitary adenoma. Multiple pigmented nevi were also noted without overt short stature and cubitus valgus. Chromosome analysis revealed that she had contracted Turner syndrome with 47,XXX/45,X/46,XX mosaicism. Transsphenoidal resection of the tumor decreased serum GH and IGF-I levels, but the edema was not improved. Both premature ovarian failure and hypertension appeared after surgery. This case may indicate the important relationships between GH/IGF-I and Turner syndrome.
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Affiliation(s)
- Masanori Yamazaki
- Department of Aging Medicine and Geriatrics, Division of Medicine, Institute on Aging and Adaptation, Shinshu University Graduate School, Matsumoto.
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45
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Abstract
Signaling through the type 1 IGF receptor (IGF1R) after interaction with IGF-I is crucial to the normal brain development. Manipulations of the mouse genome leading to changes in the expression of IGF-I or IGF1R significantly alters brain growth, such that IGF-I overexpression leads to brain overgrowth, whereas null mutations in either IGF-I or the IGF1R result in brain growth retardation. IGF-I signaling stimulates the proliferation, survival, and differentiation of each of the major neural lineages, neurons, oligodendrocytes, and astrocytes, as well as possibly influencing neural stem cells. During embryonic life, IGF-I stimulates neuron progenitor proliferation, whereas later it promotes neuron survival, neuritic outgrowth, and synaptogenesis. IGF-I also stimulates oligodendrocyte progenitor proliferation although inhibiting apoptosis in oligodendrocyte lineage cells and stimulating myelin production. These pleiotropic IGF-I activities indicate that other factors provide instructive signals for specific cellular events and that IGF-I acts to facilitate them. Studies of the few humans with IGF-I and/or IGF1R gene mutations indicate that IGF-I serves a similar role in man.
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Affiliation(s)
- A Joseph D'Ercole
- Department of Pediatrics, CB 7039, University of North Carolina, Chapel Hill, North Carolina 27599-7039, USA.
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46
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Satterfield MC, Hayashi K, Song G, Black SG, Bazer FW, Spencer TE. Progesterone regulates FGF10, MET, IGFBP1, and IGFBP3 in the endometrium of the ovine uterus. Biol Reprod 2008; 79:1226-36. [PMID: 18753603 DOI: 10.1095/biolreprod.108.071787] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Progesterone (P4) is unequivocally required to maintain a uterine environment conducive to pregnancy. This study investigated the effects of P4 treatment on expression of selected growth factors (fibroblast growth factor 7 [FGF7], FGF10, hepatocyte growth factor [HGF], and insulin-like growth factors [IGF1 and IGF2]), their receptors (MET, FGFR2(IIIB), and IGF1R), and IGF binding proteins (IGFBPs) in the ovine uterus. Ewes received daily injections of corn oil vehicle (CO) or 25 mg of P4 in vehicle from 36 h after mating (Day 0) to hysterectomy on Day 9 or Day 12. Another group received P4 to Day 8 and 75 mg of mifepristone (RU486, a P4 receptor antagonist) from Day 8 through Day 12. Endometrial FGF10 mRNA levels increased between Day 9 and Day 12 and in response to P4 on Day 9 in CO-treated ewes, which had larger blastocysts, and were substantially reduced in P4+RU486-treated ewes, which had no blastocysts on Day 12. Endometrial FGF7 or HGF mRNA levels were not affected by day or reduced by RU486 treatment, but MET mRNA levels were higher in P4-treated ewes on Day 9 and Day 12. Levels of IGF1, IGF2, and IGF1R mRNA in the endometria were not affected by early P4 treatment. Although stromal IGFBPs were unaffected by P4, levels of IGFBP1 and IGFBP3 mRNA in uterine luminal epithelia were increased substantially between Day 9 and Day 12 of pregnancy in CO-treated ewes and on Day 9 in early P4-treated ewes. Therefore, FGF10, MET, IGFBP1, and IGFBP3 are P4-regulated factors within the endometrium of the ovine uterus that have potential effects on endometrial function and peri-implantation blastocyst growth and development.
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Affiliation(s)
- M Carey Satterfield
- Center for Animal Biotechnology and Genomics, Department of Animal Science, Texas A&M University, College Station, Texas 77843-2471, USA
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47
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Gross J, Machulik A, Moller R, Fuchs J, Amarjargal N, Ungethüm U, Kuban RJ, Szczepek AJ, Haupt H, Mazurek B. MRNA expression of members of the IGF system in the organ of Corti, the modiolus and the stria vascularis of newborn rats. Growth Factors 2008; 26:180-91. [PMID: 19378418 DOI: 10.1080/08977190802194317] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
We analyzed the mRNA expression of the insulin-like growth factor (IGF) family genes and of selected downstream pathway genes using the Affymetrix microarray system and confirmatory RT-PCR in the freshly prepared organ of Corti (OC), modiolus (MOD) and stria vascularis (SV) from neonatal rats (3-5 days old) and after 24h in culture. Among the seven members of the IGF family analyzed in this paper, IGF1, IGF2 and IGF-binding protein (IGFBP2) had the highest basal expression in all regions. Preparatory stress and culture increased the expression of IGF2, IGFBP2, IGFBP3, IGFBP5, glucose transporterl (GLUT1), signal transducer, and activator of transcription3 (STAT3), phosphoinositide-3-kinase regulatory subunit (Pik3r1), Jun oncogene (c-jun) and decreased that of mitogen-activated protein kinases MAPK3 and MAPK14 in all regions. Region-specific changes were observed in OC (GLUT1), MOD (IGFBP3 and c-jun) and SV (IGF2 and IGFBP2).
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Affiliation(s)
- Johann Gross
- Molecular Biology Research Laboratory, Department of Otorhinolaryngology, Charité-Universitätsmedizin Berlin, Berlin, Germany.
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48
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Abstract
Growth hormone (GH) is widely used as a performance-enhancing drug. One of its best-characterized effects is increasing levels of circulating insulin-like growth factor I (IGF-I), which is primarily of hepatic origin. It also induces synthesis of IGF-I in most non-hepatic tissues. The effects of GH in promoting postnatal body growth are IGF-I dependent, but IGF-I-independent functions are beginning to be elucidated. Although benefits of GH administration have been reported for those who suffer from GH deficiency, there is currently very little evidence to support an anabolic role for supraphysiological levels of systemic GH or IGF-I in skeletal muscle of healthy individuals. There may be other performance-enhancing effects of GH. In contrast, the hypertrophic effects of muscle-specific IGF-I infusion are well documented in animal models and muscle cell culture systems. Studies examining the molecular responses to hypertrophic stimuli in animals and humans frequently cite upregulation of IGF-I messenger RNA or immunoreactivity. The circulatory/systemic (endocrine) and local (autocrine/paracrine) effects of GH and IGF-I may have distinct effects on muscle mass regulation.
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49
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Dilly AK, Rajala RVS. Insulin growth factor 1 receptor/PI3K/AKT survival pathway in outer segment membranes of rod photoreceptors. Invest Ophthalmol Vis Sci 2008; 49:4765-73. [PMID: 18566464 DOI: 10.1167/iovs.08-2286] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
PURPOSE The authors previously reported that physiological light induces the tyrosine phosphorylation of insulin receptors (IRs), which leads to the activation of the phosphoinositide 3-kinase (PI3K) and Akt (serine/threonine protein kinase B) survival pathway in rod photoreceptor cells. Tissue-specific deletion of IRs from photoreceptors resulted in stress-induced photoreceptor degeneration. Insulin growth factor 1 receptor (IGF-1R) is highly related in sequence and structure to the IR and shares 70% sequence identity overall and 84% identity within the tyrosine kinase domain. The role of IGF-1R in photoreceptor function is unknown. In this study the authors examined IGF-1R signaling in rod outer segment (ROS) membranes. METHODS IGF-1R localization was examined in the plasma and disc membranes of ROS. Activation of the IGF-1R/PI3K/Akt pathway was analyzed using specific antibodies against phospho-tyrosine, IGF-1R, and phospho-Akt. PI3K activity was determined in the anti-phospho-tyrosine and anti-IGF-1R immunoprecipitates. Glutathione-S-transferase fusion proteins containing two Src homology 2 (SH2) domains of the p85 subunit of PI3K and their mutants were used to study the molecular interaction between IGF-1R and p85. In vivo IGF-1R signaling was studied in rats exposed to physiological light or to constant light. RESULTS IGF-1R is predominately localized to plasma membranes of ROS. These studies indicate that light stress results in an increase in tyrosine phosphorylation of IGF-1R and an increase in PI3K enzyme activity in anti-phosphotyrosine and anti-IGF-1R immunoprecipitates of ROS and retinal homogenates. The authors observed that light stress induces tyrosine phosphorylation of IGF-1R in ROS membranes, which leads to the binding of p85 through N-SH2 and C-SH2 domains. Finally, the authors observed a significant activation of Akt in light-stressed retinas, indicating activation of the Akt survival pathway downstream of IGF-1R activation. CONCLUSIONS Light stress induced the activation of PI3K through activation and binding of IGF-1R, which leads to activation of the Akt survival pathway in photoreceptors.
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Affiliation(s)
- Ashok K Dilly
- Department of Ophthalmology, Dean A McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma 73104, USA
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