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Marassi M, Morieri ML, Sanga V, Ceolotto G, Avogaro A, Fadini GP. The Elusive Nature of ABCC8-related Maturity-Onset Diabetes of the Young (ABCC8-MODY). A Review of the Literature and Case Discussion. Curr Diab Rep 2024; 24:197-206. [PMID: 38980630 PMCID: PMC11303576 DOI: 10.1007/s11892-024-01547-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/21/2024] [Indexed: 07/10/2024]
Abstract
PURPOSE OF REVIEW Maturity-onset diabetes of the young (MODY) are monogenic forms of diabetes resulting from genetic defects, usually transmitted in an autosomal dominant fashion, leading to β-cell dysfunction. Due to the lack of homogeneous clinical features and univocal diagnostic criteria, MODY is often misdiagnosed as type 1 or type 2 diabetes, hence its diagnosis relies mostly on genetic testing. Fourteen subtypes of MODY have been described to date. Here, we review ABCC8-MODY pathophysiology, genetic and clinical features, and current therapeutic options. RECENT FINDINGS ABCC8-MODY is caused by mutations in the adenosine triphosphate (ATP)-binding cassette transporter subfamily C member 8 (ABCC8) gene, involved in the regulation of insulin secretion. The complexity of ABCC8-MODY genetic picture is mirrored by a variety of clinical manifestations, encompassing a wide spectrum of disease severity. Such inconsistency of genotype-phenotype correlation has not been fully understood. A correct diagnosis is crucial for the choice of adequate treatment and outcome improvement. By targeting the defective gene product, sulfonylureas are the preferred medications in ABCC8-MODY, although efficacy vary substantially. We illustrate three case reports in whom a diagnosis of ABCC8-MODY was suspected after the identification of novel ABCC8 variants that turned out to be of unknown significance. We discuss that careful interpretation of genetic testing is needed even on the background of a suggestive clinical context. We highlight the need for further research to unravel ABCC8-MODY disease mechanisms, as well as to clarify the pathogenicity of identified ABCC8 variants and their influence on clinical presentation and response to therapy.
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Affiliation(s)
- Marella Marassi
- Department of Medicine, University of Padova, Via Giustiniani 2, Padua, 35100, Italy
| | - Mario Luca Morieri
- Department of Medicine, University of Padova, Via Giustiniani 2, Padua, 35100, Italy
| | - Viola Sanga
- Department of Medicine, University of Padova, Via Giustiniani 2, Padua, 35100, Italy
| | - Giulio Ceolotto
- Department of Medicine, University of Padova, Via Giustiniani 2, Padua, 35100, Italy
| | - Angelo Avogaro
- Department of Medicine, University of Padova, Via Giustiniani 2, Padua, 35100, Italy
| | - Gian Paolo Fadini
- Department of Medicine, University of Padova, Via Giustiniani 2, Padua, 35100, Italy.
- Veneto Institute of Molecular Medicine, Padua, 35100, Italy.
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Larsen AR, Brusgaard K, Christesen HT, Detlefsen S. Genotype-histotype-phenotype correlations in hyperinsulinemic hypoglycemia. Histol Histopathol 2024; 39:817-844. [PMID: 38305063 DOI: 10.14670/hh-18-709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
Hyperinsulinemic hypoglycemia (HH) of pancreatic origin includes congenital hyperinsulinism (CHI), insulinoma, insulinomatosis, and adult-onset non-insulinoma persistent hyperinsulinemic hypoglycemia syndrome (NI-PHHS). In this review, we describe the genotype-histotype-phenotype correlations in HH and their therapeutic implications. CHI can occur from birth or later on in life. Histologically, diffuse CHI shows diffuse beta cell hypertrophy with a few giant nuclei per islet of Langerhans, most frequently caused by loss-of-function mutations in ABCC8 or KCNJ11. Focal CHI is histologically characterized by focal adenomatous hyperplasia consisting of confluent hyperplastic islets, caused by a paternal ABCC8/KCNJ11 mutation combined with paternal uniparental disomy of 11p15. CHI in Beckwith-Wiedemann syndrome is caused by mosaic changes in the imprinting region 11p15.4-11p15.5, leading to segmental or diffuse overgrowth of endocrine tissue in the pancreas. Morphological mosaicism of pancreatic islets is characterized by occurence of hyperplastic (type 1) islets in one or a few lobules and small (type 2) islets in the entire pancreas. Other rare genetic causes of CHI show less characteristic or unspecific histology. HH with a predominant adult onset includes insulinomas, which are pancreatic insulin-producing endocrine neoplasms, in some cases with metastatic potential. Insulinomas occur sporadically or as part of multiple endocrine neoplasia type 1 due to MEN1 mutations. MAFA mutations may histologically lead to insulinomatosis with insulin-producing neuroendocrine microadenomas or neuroendocrine neoplasms. NI-PHHS is mainly seen in adults and shows slight histological changes in some patients, which have been defined as major and minor criteria. The genetic cause is unknown in most cases. The diagnosis of HH, as defined by genetic, histological, and phenotypic features, has important implications for patient management and outcome.
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Affiliation(s)
- Annette Rønholt Larsen
- Hans Christian Andersen Children's Hospital, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
- Odense Pancreas Center (OPAC), Odense University Hospital, Odense, Denmark
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
- Steno Diabetes Center, Odense University Hospital, Odense, Denmark
| | - Klaus Brusgaard
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
- Odense Pancreas Center (OPAC), Odense University Hospital, Odense, Denmark
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
- Steno Diabetes Center, Odense University Hospital, Odense, Denmark
| | - Henrik Thybo Christesen
- Hans Christian Andersen Children's Hospital, Odense University Hospital, Odense, Denmark
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
- Odense Pancreas Center (OPAC), Odense University Hospital, Odense, Denmark
- Steno Diabetes Center, Odense University Hospital, Odense, Denmark
| | - Sönke Detlefsen
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
- Odense Pancreas Center (OPAC), Odense University Hospital, Odense, Denmark
- Department of Pathology, Odense University Hospital, Odense, Denmark.
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Butnariu LI, Bizim DA, Păduraru G, Păduraru L, Moisă ȘM, Popa S, Gimiga N, Ghiga G, Bădescu MC, Lupu A, Vasiliu I, Trandafir LM. Congenital Hyperinsulinism Caused by Mutations in ABCC8 Gene Associated with Early-Onset Neonatal Hypoglycemia: Genetic Heterogeneity Correlated with Phenotypic Variability. Int J Mol Sci 2024; 25:5533. [PMID: 38791571 PMCID: PMC11122115 DOI: 10.3390/ijms25105533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 05/14/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024] Open
Abstract
Congenital hyperinsulinism (CHI) is a rare disorder of glucose metabolism and is the most common cause of severe and persistent hypoglycemia (hyperinsulinemic hypoglycemia, HH) in the neonatal period and childhood. Most cases are caused by mutations in the ABCC8 and KCNJ11 genes that encode the ATP-sensitive potassium channel (KATP). We present the correlation between genetic heterogeneity and the variable phenotype in patients with early-onset HH caused by ABCC8 gene mutations. In the first patient, who presented persistent severe hypoglycemia since the first day of life, molecular genetic testing revealed the presence of a homozygous mutation in the ABCC8 gene [deletion in the ABCC8 gene c.(2390+1_2391-1)_(3329+1_3330-1)del] that correlated with a diffuse form of hyperinsulinism (the parents being healthy heterozygous carriers). In the second patient, the onset was on the third day of life with severe hypoglycemia, and genetic testing identified a heterozygous mutation in the ABCC8 gene c.1792C>T (p.Arg598*) inherited on the paternal line, which led to the diagnosis of the focal form of hyperinsulinism. To locate the focal lesions, (18)F-DOPA (3,4-dihydroxy-6-[18F]fluoro-L-phenylalanine) positron emission tomography/computed tomography (PET/CT) was recommended (an investigation that cannot be carried out in the country), but the parents refused to carry out the investigation abroad. In this case, early surgical treatment could have been curative. In addition, the second child also presented secondary adrenal insufficiency requiring replacement therapy. At the same time, she developed early recurrent seizures that required antiepileptic treatment. We emphasize the importance of molecular genetic testing for diagnosis, management and genetic counseling in patients with HH.
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Affiliation(s)
- Lăcrămioara Ionela Butnariu
- Department of Medical Genetics, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania;
| | - Delia Andreia Bizim
- Departament of Diabetes, Saint Mary’s Emergency Children Hospital, 700309 Iasi, Romania
| | - Gabriela Păduraru
- Department of Mother and Child, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (G.P.); (Ș.M.M.); (N.G.); (G.G.); (A.L.); (L.M.T.)
| | - Luminița Păduraru
- Department of Mother and Child, Division Neonatology, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania;
| | - Ștefana Maria Moisă
- Department of Mother and Child, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (G.P.); (Ș.M.M.); (N.G.); (G.G.); (A.L.); (L.M.T.)
| | - Setalia Popa
- Department of Medical Genetics, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania;
| | - Nicoleta Gimiga
- Department of Mother and Child, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (G.P.); (Ș.M.M.); (N.G.); (G.G.); (A.L.); (L.M.T.)
| | - Gabriela Ghiga
- Department of Mother and Child, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (G.P.); (Ș.M.M.); (N.G.); (G.G.); (A.L.); (L.M.T.)
| | - Minerva Codruța Bădescu
- Department of Internal Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 16 University Street, 700115 Iasi, Romania;
| | - Ancuta Lupu
- Department of Mother and Child, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (G.P.); (Ș.M.M.); (N.G.); (G.G.); (A.L.); (L.M.T.)
| | - Ioana Vasiliu
- Department of Morphofunctional Sciences II, Grigore T. Popa University of Medicine and Pharmacy, 700115 Iasi, Romania;
| | - Laura Mihaela Trandafir
- Department of Mother and Child, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (G.P.); (Ș.M.M.); (N.G.); (G.G.); (A.L.); (L.M.T.)
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ElSheikh A, Shyng SL. K ATP channel mutations in congenital hyperinsulinism: Progress and challenges towards mechanism-based therapies. Front Endocrinol (Lausanne) 2023; 14:1161117. [PMID: 37056678 PMCID: PMC10086357 DOI: 10.3389/fendo.2023.1161117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 03/13/2023] [Indexed: 03/30/2023] Open
Abstract
Congenital hyperinsulinism (CHI) is the most common cause of persistent hypoglycemia in infancy/childhood and is a serious condition associated with severe recurrent attacks of hypoglycemia due to dysregulated insulin secretion. Timely diagnosis and effective treatment are crucial to prevent severe hypoglycemia that may lead to life-long neurological complications. In pancreatic β-cells, adenosine triphosphate (ATP)-sensitive K+ (KATP) channels are a central regulator of insulin secretion vital for glucose homeostasis. Genetic defects that lead to loss of expression or function of KATP channels are the most common cause of HI (KATP-HI). Much progress has been made in our understanding of the molecular genetics and pathophysiology of KATP-HI in the past decades; however, treatment remains challenging, in particular for patients with diffuse disease who do not respond to the KATP channel activator diazoxide. In this review, we discuss current approaches and limitations on the diagnosis and treatment of KATP-HI, and offer perspectives on alternative therapeutic strategies.
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Affiliation(s)
- Assmaa ElSheikh
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, United States
- Department of Medical Biochemistry, Tanta University, Tanta, Egypt
| | - Show-Ling Shyng
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, United States
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Gundogdu S, Ciftci M, Atay E, Ayaz A, Ceran O, Atay Z. Clinical and laboratory evaluation of children with congenital hyperinsulinism: a single center experience. J Pediatr Endocrinol Metab 2023; 36:53-57. [PMID: 36409572 DOI: 10.1515/jpem-2022-0155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 10/26/2022] [Indexed: 11/22/2022]
Abstract
OBJECTIVES To evaluate and present the data regarding clinical, laboratory, radiological and the results of molecular genetic analysis of patients with hyperinsulinemic hypoglycemia in our clinics. METHODS A total of 9 patients with CHI followed at Istanbul Medipol University. Data related to gender, age at presentation, birth weight, gestational age, consanguinity, glucose and insulin levels at diagnosis, treatment modalities, response to treatment, the results of genetic analysis and radiological evaluation were gathered from the files. RESULTS The oldest age at presentation was 6 months. KATP channel mutation was detected in 55% (n: 5). Diazoxide unresponsiveness was seen in 55% (n: 5). Octreotide was effective in 3 of them. 18F-DOPA PET performed in 4 diazoxide unresponsive patients revealed focal lesion in 3 of them. Spontaneous remission rate was 66% (n:6). All the patients with normal genetic result achieved spontaneous remission. Spontaneous remission was even noted in diazoxide unresponsive patients and in patients with focal lesion on 18F-DOPA PET. CONCLUSIONS Clinical presentation of patients with congenital hypereinsulinism is heterogeneous. Spontaneous remission rate is quite high even in patients with severe clinical presentation. It is important to develop methods that can predict which patients will have spontaneous remission. Reporting the clinical and laboratory data of each patient is important and will help to guide the management of patients with hyperinsulinemic hypoglycemia.
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Affiliation(s)
- Semra Gundogdu
- Department of Neonatalogy, Istanbul Medipol University, School of Medicine, Istanbul, Turkey
| | - Mustafa Ciftci
- Department of Pediatrics, Istanbul Medipol University, School of Medicine, Istanbul, Turkey
| | - Enver Atay
- Department of Pediatrics, Istanbul Medipol University, School of Medicine, Istanbul, Turkey
| | - Akif Ayaz
- Genetic Diseases Assessment Center, Istanbul Medipol University, Istanbul, Turkey
| | - Omer Ceran
- Department of Pediatrics, Istanbul Medipol University, School of Medicine, Istanbul, Turkey
| | - Zeynep Atay
- Department of Pediatric Endocrinology, Istanbul Medipol University, School of Medicine, Istanbul, Turkey
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6
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Yorifuji T, Watanabe Y, Kitayama K, Yamada Y, Higuchi S, Mori J, Kato M, Takahashi T, Okuda T, Aoyama T. Targeted gene panel analysis of Japanese patients with maturity-onset diabetes of the young-like diabetes mellitus: Roles of inactivating variants in the ABCC8 and insulin resistance genes. J Diabetes Investig 2022; 14:387-403. [PMID: 36504295 PMCID: PMC9951579 DOI: 10.1111/jdi.13957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 10/23/2022] [Accepted: 11/24/2022] [Indexed: 12/14/2022] Open
Abstract
AIMS/INTRODUCTION To investigate the genetic background of Japanese patients with suspected maturity-onset diabetes of the young (MODY). MATERIALS AND METHODS On 340 proband patients referred from across Japan, genomic variants were analyzed using a targeted multigene panel analysis combined with the multiplex ligation probe amplification (MLPA) analysis, mitochondrial m.3243A > G analysis and methylation-specific polymerase chain reaction of the imprinted 6q24 locus. Pathogenic/likely pathogenic variants were listed according to the 2015 American College of Medical Genetics and Genomics and the Association for Molecular Pathology criteria. Additionally, variants with a population frequency <0.001 and Combined Annotation Dependent Depletion score >20 (CS >20) were listed as rare variants of uncertain significance-CS >20. RESULTS A total of 157 pathogenic/likely pathogenic variants and 44 rare variants of uncertain significance-CS >20 were identified. In the pathogenic/likely pathogenic variants, alterations in the GCK gene were the most common (82, 52.2%) followed by HNF1A (29, 18.5%), HNF4A (13, 8.3%) and HNF1B (13, 8.3%). One patient was a 29.5% mosaic with a truncating INSR variant. In the rare variants of uncertain significance-CS >20, 20 (45.5%) were in the genes coding for the adenosine triphosphate-sensitive potassium channel, KCNJ11 or ABCC8, and four were in the genes of the insulin-signaling pathway, INSR and PIK3R1. Four variants in ABCC8 were previously reported in patients with congenital hyperinsulinism, suggesting the inactivating nature of these variants, and at least two of our patients had a history of congenital hyperinsulinism evolving into diabetes. In two patients with INSR or PIK3R1 variants, insulin resistance was evident at diagnosis. CONCLUSIONS Causative genomic variants could be identified in at least 46.2% of clinically suspected MODY patients. ABCC8-MODY with inactivating variants could represent a distinct category of MODY. Genes of insulin resistance should be included in the sequencing panel for MODY.
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Affiliation(s)
- Tohru Yorifuji
- Division of Pediatric Endocrinology and MetabolismChildren's Medical Center, Osaka City General HospitalOsakaJapan,Department of Genetic MedicineOsaka City General HospitalOsakaJapan,Clinical Research CenterOsaka City General HospitalOsakaJapan,2nd Department of Internal MedicineDate Red Cross HospitalDate, HokkaidoJapan
| | - Yoh Watanabe
- Division of Pediatric Endocrinology and MetabolismChildren's Medical Center, Osaka City General HospitalOsakaJapan
| | - Kana Kitayama
- Division of Pediatric Endocrinology and MetabolismChildren's Medical Center, Osaka City General HospitalOsakaJapan
| | - Yuki Yamada
- Division of Pediatric Endocrinology and MetabolismChildren's Medical Center, Osaka City General HospitalOsakaJapan
| | - Shinji Higuchi
- Division of Pediatric Endocrinology and MetabolismChildren's Medical Center, Osaka City General HospitalOsakaJapan
| | - Jun Mori
- Division of Pediatric Endocrinology and MetabolismChildren's Medical Center, Osaka City General HospitalOsakaJapan
| | - Masaru Kato
- Department of Genetic MedicineOsaka City General HospitalOsakaJapan
| | - Toru Takahashi
- Department of Genetic MedicineOsaka City General HospitalOsakaJapan
| | - Tokuko Okuda
- Clinical Research CenterOsaka City General HospitalOsakaJapan
| | - Takane Aoyama
- Clinical Research CenterOsaka City General HospitalOsakaJapan
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Motte-Signoret E, Saint-Martin C, Bellané-Chantelot C, Portha B, Boileau P. Glucocorticoid-Induced Hyperinsulinism in a Preterm Neonate with Inherited ABCC8 Variant. Metabolites 2022; 12:metabo12090847. [PMID: 36144251 PMCID: PMC9506278 DOI: 10.3390/metabo12090847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/05/2022] [Accepted: 09/06/2022] [Indexed: 12/03/2022] Open
Abstract
Glucose homeostasis is a real challenge for extremely preterm infants (EPIs) who have both limited substrate availability and immature glucose metabolism regulation. In the first days of life, EPIs frequently develop transient glucose intolerance, which has a complex pathophysiology that associates unregulated gluconeogenesis, immature insulin secretion, and peripheral insulin resistance. In this population, glucocorticoid therapy is frequently administrated to prevent severe bronchopulmonary dysplasia. During this treatment, glucose intolerance classically increases and may lead to hyperglycemia. We report a case of neonatal hypoglycemia that was concomitant to a glucocorticoids administration, and that led to a congenital hyperinsulinism diagnosis in an EPI with a heterozygous ABCC8 variant. The variant was inherited from his mother, who had developed monogenic onset diabetes of the youth (MODY) at the age of 23. ABCC8 encodes a beta-cell potassium channel unit and causes congenital hyperinsulinism or MODY depending on the mutation location. Moreover, some mutations have been observed in the same patient to cause both hyperinsulinism in infancy and MODY in adulthood. In our case, the baby showed repeated and severe hypoglycemias, which were undoubtedly time-associated with the betamethasone intravenous administration. This hyperinsulinism was transient, and the infant has not yet developed diabetes at three years of age. We take the opportunity presented by this unusual clinical presentation to provide a review of the literature, suggesting new insights regarding the pathophysiology of the beta-pancreatic cells’ insulin secretion: glucocorticoids may potentiate basal insulin secretion in patients with ABCC8 mutation.
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Affiliation(s)
- Emmanuelle Motte-Signoret
- Department of Neonatal Intensive Care Unit, Poissy St Germain Hospital, 10 rue du Champ Gaillard, 78300 Poissy, France
- Biologie de la Reproduction, Environnement, Epigénétique et Développement (BREED), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Versailles St Quentin University—Paris-Saclay University, 78350 Jouy-en-Josas, France
- Correspondence: ; Tel.: +331-39-27-52-40; Fax: +331-39-27-44-30
| | - Cécile Saint-Martin
- Department of Medical Genetics, Pitié-Salpêtrière Hospital, Sorbonne University, AP-HP, 75013 Paris, France
| | | | - Bernard Portha
- Unité de Biologie Fonctionnelle et Adaptive, Laboratoire B2PE, CNRS UMR 8251, Campus Grands Moulins, Université Paris Cité, 75205 Paris, France
| | - Pascal Boileau
- Department of Neonatal Intensive Care Unit, Poissy St Germain Hospital, 10 rue du Champ Gaillard, 78300 Poissy, France
- Physiologie et Physiopathologie Endocriniennes, Inserm, Paris-Saclay University, 94276 Le Kremlin-Bicêtre, France
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8
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Boodhansingh KE, Yang Z, Li C, Chen P, Lord K, Becker SA, States LJ, Adzick NS, Bhatti T, Shyng SL, Ganguly A, Stanley CA, De Leon DD. Localized islet nuclear enlargement hyperinsulinism (LINE-HI) due to ABCC8 and GCK mosaic mutations. Eur J Endocrinol 2022; 187:301-313. [PMID: 35674212 PMCID: PMC9339501 DOI: 10.1530/eje-21-1095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 06/07/2022] [Indexed: 11/08/2022]
Abstract
Objective Congenital hyperinsulinism (HI) is the most common cause of persistent hypoglycemia in children. In addition to typical focal or diffuse HI, some cases with diazoxide-unresponsive congenital HI have atypical pancreatic histology termed Localized Islet Nuclear Enlargement (LINE) or mosaic HI, characterized by histologic features similar to diffuse HI, but confined to only a region of pancreas. Our objective was to characterize the phenotype and genotype of children with LINE-HI. Design The phenotype and genotype features of 12 children with pancreatic histology consistent with LINE-HI were examined. Methods We compiled clinical features of 12 children with LINE-HI and performed next-generation sequencing on specimens of pancreas from eight of these children to look for mosaic mutations in genes known to be associated with diazoxide-unresponsive HI (ABCC8, KCNJ11, and GCK). Results Children with LINE-HI had lower birth weights and later ages of presentation compared to children with typical focal or diffuse HI. Partial pancreatectomy in LINE-HI cases resulted in euglycemia in 75% of cases; no cases have developed diabetes. Low-level mosaic mutations were identified in the pancreas of six cases with LINE-HI (three in ABCC8, three in GCK). Expression studies confirmed that all novel mutations were pathogenic. Conclusion These results indicate that post-zygotic low-level mosaic mutations of known HI genes are responsible for some cases of LINE-HI that lack an identifiable germ-line mutation and that partial pancreatectomy may be curative for these cases.
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Affiliation(s)
- Kara E. Boodhansingh
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Zhongying Yang
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon
| | - Changhong Li
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Pan Chen
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Katherine Lord
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Susan A. Becker
- Department of Radiology, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Lisa J. States
- Department of Radiology, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
- Department of Radiology, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - N. Scott Adzick
- Department of Surgery, The Children’s Hospital of Philadelphia, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104
| | - Tricia Bhatti
- Department of Pathology, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
- Department of Pathology, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Show-Ling Shyng
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, Oregon
| | - Arupa Ganguly
- Department of Genetics, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Charles A. Stanley
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Diva D. De Leon
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
- Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
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9
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Novel Compound Heterozygous Variants of the ABCC8 Gene Warrant Identification of Pancreatic Histology in Infant with Diazoxide-unresponsive Congenital Hyperinsulinism. CHILDREN-BASEL 2021; 8:children8100836. [PMID: 34682101 PMCID: PMC8534644 DOI: 10.3390/children8100836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/18/2021] [Accepted: 09/20/2021] [Indexed: 11/21/2022]
Abstract
Congenital hyperinsulinism (CHI) is characterized by dysregulated insulin secretion, resulting in severe hypoglycemia. Mutations in the ABCC8 and KCNJ11 genes encoding KATP channels in beta cells of the pancreas are common among patients with CHI. Autosomal recessive CHI with diffuse involvement is the most common type of CHI among Saudi patients. It is relatively common for patients with autosomal recessive CHI to be medically unresponsive and undergo pancreatectomy. In this case report, we describe novel compound heterozygous variants in the ABCC8 gene in a Saudi infant that caused diazoxide-unresponsive CHI. The variants included a monoallelic paternally inherited variant that has been previously reported to cause a focal form of CHI and a maternally inherited variant of unknown significance (VUS). The severity of CHI in this patient was mild over the one-year follow-up period, with a near-optimal glycemic response on a low dose of octreotide. We suspected an atypical subtype of histological involvement in the patient. In this report, we highlight the phenotypic spectrum of novel compound heterozygous variants in a patient with CHI and consider that the report can help establish the pathogenicity of the VUS.
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Laimon W, Aboelenin HM, El Tantawi NT. Clinical characteristics, outcome, and predictors of neurological sequelae of persistent congenital hyperinsulinism: A single tertiary center experience. Pediatr Diabetes 2021; 22:388-399. [PMID: 33528087 DOI: 10.1111/pedi.13186] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 11/09/2020] [Accepted: 12/29/2020] [Indexed: 11/29/2022] Open
Abstract
AIM Congenital hyperinsulinism (CHI) is a heterogeneous disease with variable genetic etiology, histopathology, and clinical phenotype. This study aims to describe the clinical characteristics of persistent CHI and evaluate long-term neurological outcome and its risk factors in a cohort of Egyptian children. METHODS Clinical, genetic, and biochemical data of 42 patients with CHI were collected. Patients were invited for neurological assessment, electroencephalogram, and magnetic resonance imaging of the brain. RESULTS ABCC8 mutation was found in (61%) of cases who underwent genetic testing (17/28). Five cases with homozygous biparental ABCC8 mutation responded to combined diazoxide and octreotide without needing surgery. Seven out of twenty-one patients who had pancreatectomy (33%) developed diabetes after a median period of 4.8 (range:1-10) years following surgery. Fifty-five percent of our patients had neurodevelopmental impairment at follow-up. Logistic regression analysis has shown that delayed referral to tertiary centre for more than 8 days, delayed diagnosis of CHI for more than 14 days and hospital admission for more than 30 days, are significant predictors of unfavorable neurological sequelae in CHI; (OR = 12.7 [2.56], p = 0.001), (OR = 12.7 [2.9-56], p = 0.001), and (OR = 3.8 [0.14.5], p = 0.043), respectively. CONCLUSIONS ABCC8 mutation was the commonest genetic mutation underlying CHI in this study group. CHI cases with biparental homozygous ABCC8 mutation may show response to combined octreotide and diazoxide therapy. More than half of our patients had neurodevelopmental impairment at follow-up. Delayed referral to expert centre, delayed diagnosis and longer hospital stay are significant predictors of neurological disability in CHI cases.
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Affiliation(s)
- Wafaa Laimon
- Pediatric Endocrinology and Diabetes Unit, Department of Pediatrics, Mansoura Faculty of Medicine, Mansoura University, Mansoura University Children's Hospital, Mansoura, Egypt
| | - Hadil Mohamed Aboelenin
- Pediatric Endocrinology and Diabetes Unit, Department of Pediatrics, Mansoura Faculty of Medicine, Mansoura University, Mansoura University Children's Hospital, Mansoura, Egypt
| | - Noha T El Tantawi
- Pediatric Neurology Unit, Department of Pediatrics, Mansoura Faculty of Medicine, Mansoura University, Mansoura University Children's Hospital, Mansoura, Egypt
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11
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Sanchez Caballero L, Gorgogietas V, Arroyo MN, Igoillo-Esteve M. Molecular mechanisms of β-cell dysfunction and death in monogenic forms of diabetes. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2021; 359:139-256. [PMID: 33832649 DOI: 10.1016/bs.ircmb.2021.02.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Monogenetic forms of diabetes represent 1%-5% of all diabetes cases and are caused by mutations in a single gene. These mutations, that affect genes involved in pancreatic β-cell development, function and survival, or insulin regulation, may be dominant or recessive, inherited or de novo. Most patients with monogenic diabetes are very commonly misdiagnosed as having type 1 or type 2 diabetes. The severity of their symptoms depends on the nature of the mutation, the function of the affected gene and, in some cases, the influence of additional genetic or environmental factors that modulate severity and penetrance. In some patients, diabetes is accompanied by other syndromic features such as deafness, blindness, microcephaly, liver and intestinal defects, among others. The age of diabetes onset may also vary from neonatal until early adulthood manifestations. Since the different mutations result in diverse clinical presentations, patients usually need different treatments that range from just diet and exercise, to the requirement of exogenous insulin or other hypoglycemic drugs, e.g., sulfonylureas or glucagon-like peptide 1 analogs to control their glycemia. As a consequence, awareness and correct diagnosis are crucial for the proper management and treatment of monogenic diabetes patients. In this chapter, we describe mutations causing different monogenic forms of diabetes associated with inadequate pancreas development or impaired β-cell function and survival, and discuss the molecular mechanisms involved in β-cell demise.
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Affiliation(s)
- Laura Sanchez Caballero
- ULB Center for Diabetes Research (UCDR), Université Libre de Bruxelles, Brussels, Belgium. http://www.ucdr.be/
| | - Vyron Gorgogietas
- ULB Center for Diabetes Research (UCDR), Université Libre de Bruxelles, Brussels, Belgium. http://www.ucdr.be/
| | - Maria Nicol Arroyo
- ULB Center for Diabetes Research (UCDR), Université Libre de Bruxelles, Brussels, Belgium. http://www.ucdr.be/
| | - Mariana Igoillo-Esteve
- ULB Center for Diabetes Research (UCDR), Université Libre de Bruxelles, Brussels, Belgium. http://www.ucdr.be/.
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12
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Production and purification of ATP-sensitive potassium channel particles for cryo-electron microscopy. Methods Enzymol 2021; 653:121-150. [PMID: 34099169 DOI: 10.1016/bs.mie.2021.02.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
ATP-sensitive potassium (KATP) channels are multimeric protein complexes made of four inward rectifying potassium channel (Kir6.x) subunits and four ABC protein sulfonylurea receptor (SURx) subunits. Kir6.x subunits form the potassium ion conducting pore of the channel, and SURx functions to regulate Kir6.x. Kir6.x and SURx are uniquely dependent on each other for expression and function. In pancreatic β-cells, channels comprising SUR1 and Kir6.2 mediate glucose-stimulated insulin secretion and are the targets of antidiabetic sulfonylureas. Mutations in genes encoding SUR1 or Kir6.2 are linked to insulin secretion disorders, with loss- or gain-of-function mutations causing congenital hyperinsulinism or neonatal diabetes mellitus, respectively. Defects in the KATP channel in other tissues underlie human diseases of the cardiovascular and nervous systems. Key to understanding how channels are regulated by physiological and pharmacological ligands and how mutations disrupt channel assembly or gating to cause disease is the ability to observe structural changes associated with subunit interactions and ligand binding. While recent advances in the structural method of single-particle cryo-electron microscopy (cryoEM) offers direct visualization of channel structures, success of obtaining high-resolution structures is dependent on highly concentrated, homogeneous KATP channel particles. In this chapter, we describe a method for expressing KATP channels in mammalian cell culture, solubilizing the channel in detergent micelles and purifying KATP channels using an affinity tag to the SURx subunit for cryoEM structural studies.
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13
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Saint-Martin C, Cauchois-Le Mière M, Rex E, Soukarieh O, Arnoux JB, Buratti J, Bouvet D, Frébourg T, Gaildrat P, Shyng SL, Bellanné-Chantelot C, Martins A. Functional characterization of ABCC8 variants of unknown significance based on bioinformatics predictions, splicing assays, and protein analyses: Benefits for the accurate diagnosis of congenital hyperinsulinism. Hum Mutat 2021; 42:408-420. [PMID: 33410562 DOI: 10.1002/humu.24164] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 12/06/2020] [Accepted: 12/31/2020] [Indexed: 12/20/2022]
Abstract
ABCC8 encodes the SUR1 subunit of the β-cell ATP-sensitive potassium channel whose loss of function causes congenital hyperinsulinism (CHI). Molecular diagnosis is critical for optimal management of CHI patients. Unfortunately, assessing the impact of ABCC8 variants on RNA splicing remains very challenging as this gene is poorly expressed in leukocytes. Here, we performed bioinformatics analysis and cell-based minigene assays to assess the impact on splicing of 13 ABCC8 variants identified in 20 CHI patients. Next, channel properties of SUR1 proteins expected to originate from minigene-detected in-frame splicing defects were analyzed after ectopic expression in COSm6 cells. Out of the analyzed variants, seven induced out-of-frame splicing defects and were therefore classified as recessive pathogenic, whereas two led to skipping of in-frame exons. Channel functional analysis of the latter demonstrated their pathogenicity. Interestingly, the common rs757110 SNP increased exon skipping in our system suggesting that it may act as a disease modifier factor. Our strategy allowed determining the pathogenicity of all selected ABCC8 variants, and CHI-inheritance pattern for 16 out of the 20 patients. This study highlights the value of combining RNA and protein functional approaches in variant interpretation and reveals the minigene splicing assay as a new tool for CHI molecular diagnostics.
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Affiliation(s)
- Cécile Saint-Martin
- Department of Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | - Marine Cauchois-Le Mière
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France.,Department of Genetics, University Hospital, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Emily Rex
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, USA
| | - Omar Soukarieh
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Jean-Baptiste Arnoux
- Department of Inherited Metabolic Disease, Necker-Enfants Malades University Hospital, AP-HP, Paris, France
| | - Julien Buratti
- Department of Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | - Delphine Bouvet
- Department of Genetics, AP-HP Pitié-Salpêtrière Hospital, Sorbonne University, Paris, France
| | - Thierry Frébourg
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France.,Department of Genetics, University Hospital, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Pascaline Gaildrat
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
| | - Show-Ling Shyng
- Department of Chemical Physiology and Biochemistry, Oregon Health & Science University, Portland, OR, USA
| | | | - Alexandra Martins
- Inserm U1245, UFR de Médecine et Pharmacie, UNIROUEN, Normandie University, Normandy Centre for Genomic and Personalized Medicine, Rouen, France
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14
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Tang C, Meng L, Zhang P, Liang X, Dang C, Liang H, Wu J, Lan H, Qin Y. Case Report: A Novel ABCC8 Variant in a Chinese Pedigree of Maturity-Onset Diabetes of the Young. Front Endocrinol (Lausanne) 2021; 12:758723. [PMID: 35002955 PMCID: PMC8734027 DOI: 10.3389/fendo.2021.758723] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Accepted: 11/30/2021] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND We aimed to analyze a novel ABCC8 variant of a Chinese patient with suspected maturity-onset diabetes of the young (MODY) and to provide evidence for precise diagnosis and appropriate treatment. METHOD A Chinese family with suspected MODY was recruited in this study, which included a 15-year-old female patient with diabetes. Clinical data and blood samples were collected from the proband and other family members. All of the living relatives were given an oral glucose tolerance test. Next-generation sequencing was performed to identify the mutated genes in the proband. Sanger sequencing was utilized to confirm the location of the pathogenic variant in all subjects. Further treatment was referred to targeted family members according to genetic testing. RESULTS The proband was found to have a random blood glucose level of 244.8 mg/dl and an HbA1c level of 9.2%. Before this investigation, her grandparents had been diagnosed with diabetes. The second uncle, two aunts, mother, and cousin of the proband were diagnosed with diabetes by abnormal HbA1C (6.5-12.1%) and fasting blood glucose (FBG, 91.4-189.7 mg/dl). The second aunt of the proband had impaired glucose homeostasis (HbA1C = 6.4% and FBG = 88.0 mg/dl). One novel missense variant c.1432G>A (p.A478T) in exon 9 of the ABCC8 gene was detected in the proband with suspected MODY. The variant was also found in six family members with diabetes or impaired glucose homeostasis, including her second uncle, two aunts, mother, and cousin. After the treatment was switched to glimepiride, the fasting blood glucose was adjusted to 99.54 mg/dl, the 2-h postprandial blood glucose was 153.54 mg/dl, serum fructosamine was 259 μmol/l, and HbA1c was 5.8%. The glycemic control remained optimal, and no hypoglycemic episodes were observed in the living relatives. CONCLUSION This study revealed one novel missense variant of the ABCC8 gene in Chinese families. The present findings indicated that the members of this family responded to treatment with sulfonylureas as previously seen in ABCC8 MODY.
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Affiliation(s)
- Chaoyan Tang
- Department of Endocrinology, The First People's Hospital of Yulin, Yulin, China
| | - Liheng Meng
- Department of Endocrinology, First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Ping Zhang
- Department of Endocrinology, The First People's Hospital of Yulin, Yulin, China
| | - Xinghuan Liang
- Department of Endocrinology, First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Chaozhi Dang
- Department of Endocrinology, The First People's Hospital of Yulin, Yulin, China
| | - Hui Liang
- Department of Endocrinology, The First People's Hospital of Yulin, Yulin, China
| | - Junfeng Wu
- Department of Endocrinology, The First People's Hospital of Yulin, Yulin, China
| | - Haiyun Lan
- Department of Endocrinology, The First People's Hospital of Yulin, Yulin, China
| | - Yingfen Qin
- Department of Endocrinology, First Affiliated Hospital of Guangxi Medical University, Nanning, China
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15
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Taylor-Miller T, Houghton J, Munyard P, Kumar Y, Puvirajasinghe C, Giri D. Congenital hyperinsulinism due to compound heterozygous mutations in ABCC8 responsive to diazoxide therapy. J Pediatr Endocrinol Metab 2020; 33:671-674. [PMID: 32267248 DOI: 10.1515/jpem-2019-0457] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 02/18/2020] [Indexed: 11/15/2022]
Abstract
Background Congenital hyperinsulinism (CHI), a condition characterized by dysregulation of insulin secretion from the pancreatic β cells, remains one of the most common causes of hyperinsulinemic, hypoketotic hypoglycemia in the newborn period. Mutations in ABCC8 and KCNJ11 constitute the majority of genetic forms of CHI. Case presentation A term macrosomic male baby, birth weight 4.81 kg, born to non-consanguineous parents, presented on day 1 of life with severe and persistent hypoglycemia. The biochemical investigations confirmed a diagnosis of CHI. Diazoxide was started and progressively increased to 15 mg/kg/day to maintain normoglycemia. Sequence analysis identified compound heterozygous mutations in ABCC8 c.4076C>T and c.4119+1G>A inherited from the unaffected father and mother, respectively. The mutations are reported pathogenic. The patient is currently 7 months old with a sustained response to diazoxide. Conclusions Biallelic ABCC8 mutations are known to result in severe, diffuse, diazoxide-unresponsive hypoglycemia. We report a rare patient with CHI due to compound heterozygous mutations in ABCC8 responsive to diazoxide.
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Affiliation(s)
- Tashunka Taylor-Miller
- Department of Paediatric Endocrinology, Bristol Royal Hospital for Children, Bristol, UK
| | - Jayne Houghton
- Department of Molecular Genetics, University of Exeter Medical School, Exeter, UK
| | - Paul Munyard
- Department of Paediatrics, Royal Cornwall Hospitals NHS Trust, Truro, UK
| | - Yadlapalli Kumar
- Department of Paediatrics, Royal Cornwall Hospitals NHS Trust, Truro, UK
| | - Clinda Puvirajasinghe
- Great Ormond Street Hospital for Children NHS Foundation Trust, Rare and Inherited Disease Laboratory, North London Genomic Laboratory Hub, London, UK
| | - Dinesh Giri
- Consultant Paediatric Endocrinologist and Honorary Senior Lecturer, Bristol Royal Hospital for Children and University of Bristol, Bristol BS2 8BJ, UK.,Department of Paediatric Endocrinology, Department of Translational Health Sciences, University of Bristol, Bristol, UK
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16
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Rasmussen AG, Melikian M, Globa E, Detlefsen S, Rasmussen L, Petersen H, Brusgaard K, Rasmussen AH, Mortensen MB, Christesen HT. The difficult management of persistent, non-focal congenital hyperinsulinism: A retrospective review from a single, tertiary center. Pediatr Diabetes 2020; 21:441-455. [PMID: 31997554 DOI: 10.1111/pedi.12989] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 11/14/2019] [Accepted: 01/13/2020] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND/OBJECTIVE Congenital hyperinsulinism (CHI) is a rare, heterogeneous disease with transient or persistent hypoglycemia. Histologically, focal, diffuse, and atypical forms of CHI exist, and at least 11 disease-causing genes have been identified. METHODS We retrospectively evaluated the treatment and outcome of a cohort of 40 patients with non-focal, persistent CHI admitted to the International Hyperinsulinism Center, Denmark, from January 2000 to May 2017. RESULTS Twenty-two patients (55%) could not be managed with medical monotherapy (diazoxide or octreotide) and six (15%) patients developed severe potential side effects to medication. Surgery was performed in 17 (43%) patients with resection of 66% to 98% of the pancreas. Surgically treated patients had more frequently KATP -channel gene mutations (surgical treatment 12/17 vs conservative treatment 6/23, P = .013), highly severe disease (15/17 vs 13/23, P = .025) and clinical onset <30 days of age (15/17 vs 10/23, P = .004). At last follow-up at median 5.3 (range: 0.3-31.3) years of age, 31/40 (78%) patients still received medical treatment, including 12/17 (71%) after surgery. One patient developed diabetes after a 98% pancreatic resection. Problematic treatment status was seen in 7/40 (18%). Only 8 (20%) had clinical remission (three spontaneous, five after pancreatic surgery). Neurodevelopmental impairment (n = 12, 30%) was marginally associated with disease severity (P = .059). CONCLUSIONS Persistent, non-focal CHI remains difficult to manage. Neurological impairment in 30% suggests a frequent failure of prompt and adequate treatment. A high rate of problematic treatment status at follow-up demonstrates an urgent need for new medical treatment modalities.
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Affiliation(s)
- Amalie G Rasmussen
- Hans Christian Andersen Children's Hospital, Odense University Hospital, Odense, Denmark.,Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark
| | - Maria Melikian
- Department of Pediatric Endocrinology, Endrocrine Research Center, Moscow, Russia
| | - Evgenia Globa
- Department of Pediatric Endocrinology, Ukrainian Research Center of Endocrine Surgery, Kyiv, Ukraine
| | - Sönke Detlefsen
- Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark.,OPAC, Odense Pancreas Center, Odense University Hospital, Odense, Denmark.,Department of Pathology, Odense University Hospital, Odense, Denmark
| | - Lars Rasmussen
- OPAC, Odense Pancreas Center, Odense University Hospital, Odense, Denmark.,Department of Surgery, Odense University Hospital, Odense, Denmark
| | - Henrik Petersen
- Department of Nuclear Medicine, Odense University Hospital, Odense, Denmark
| | - Klaus Brusgaard
- Department of Clinical Genetics, Odense University Hospital, Odense, Denmark
| | - Annett H Rasmussen
- Hans Christian Andersen Children's Hospital, Odense University Hospital, Odense, Denmark
| | - Michael B Mortensen
- OPAC, Odense Pancreas Center, Odense University Hospital, Odense, Denmark.,Department of Surgery, Odense University Hospital, Odense, Denmark
| | - Henrik T Christesen
- Hans Christian Andersen Children's Hospital, Odense University Hospital, Odense, Denmark.,Department of Clinical Research, Faculty of Health Sciences, University of Southern Denmark, Odense, Denmark.,OPAC, Odense Pancreas Center, Odense University Hospital, Odense, Denmark
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Islam MS. Stimulus-Secretion Coupling in Beta-Cells: From Basic to Bedside. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1131:943-963. [PMID: 31646540 DOI: 10.1007/978-3-030-12457-1_37] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Insulin secretion in humans is usually induced by mixed meals, which upon ingestion, increase the plasma concentration of glucose, fatty acids, amino acids, and incretins like glucagon-like peptide 1. Beta-cells can stay in the off-mode, ready-mode or on-mode; the mode-switching being determined by the open state probability of the ATP-sensitive potassium channels, and the activity of enzymes like glucokinase, and glutamate dehydrogenase. Mitochondrial metabolism is critical for insulin secretion. A sound understanding of the intermediary metabolism, electrophysiology, and cell signaling is essential for comprehension of the entire spectrum of the stimulus-secretion coupling. Depolarization brought about by inhibition of the ATP sensitive potassium channel, together with the inward depolarizing currents through the transient receptor potential (TRP) channels, leads to electrical activities, opening of the voltage-gated calcium channels, and exocytosis of insulin. Calcium- and cAMP-signaling elicited by depolarization, and activation of G-protein-coupled receptors, including the free fatty acid receptors, are intricately connected in the form of networks at different levels. Activation of the glucagon-like peptide 1 receptor augments insulin secretion by amplifying calcium signals by calcium induced calcium release (CICR). In the treatment of type 2 diabetes, use of the sulfonylureas that act on the ATP sensitive potassium channel, damages the beta cells, which eventually fail; these drugs do not improve the cardiovascular outcomes. In contrast, drugs acting through the glucagon-like peptide-1 receptor protect the beta-cells, and improve cardiovascular outcomes. The use of the glucagon-like peptide 1 receptor agonists is increasing and that of sulfonylurea is decreasing. A better understanding of the stimulus-secretion coupling may lead to the discovery of other molecular targets for development of drugs for the prevention and treatment of type 2 diabetes.
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Affiliation(s)
- Md Shahidul Islam
- Department of Clinical Science and Education, Södersjukhuset, Research Center, Karolinska Institutet, Stockholm, Sweden. .,Department of Emergency Care and Internal Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden.
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18
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Sikimic J, Hoffmeister T, Gresch A, Kaiser J, Barthlen W, Wolke C, Wieland I, Lendeckel U, Krippeit-Drews P, Düfer M, Drews G. Possible New Strategies for the Treatment of Congenital Hyperinsulinism. Front Endocrinol (Lausanne) 2020; 11:545638. [PMID: 33193079 PMCID: PMC7653201 DOI: 10.3389/fendo.2020.545638] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 10/02/2020] [Indexed: 01/21/2023] Open
Abstract
OBJECTIVE Congenital hyperinsulinism (CHI) is a rare disease characterized by persistent hypoglycemia as a result of inappropriate insulin secretion, which can lead to irreversible neurological defects in infants. Poor efficacy and strong adverse effects of the current medications impede successful treatment. The aim of the study was to investigate new approaches to silence β-cells and thus attenuate insulin secretion. RESEARCH DESIGN AND METHODS In the scope of our research, we tested substances more selective and more potent than the gold standard diazoxide that also interact with neuroendocrine ATP-sensitive K+ (KATP) channels. Additionally, KATP channel-independent targets as Ca2+-activated K+ channels of intermediate conductance (KCa3.1) and L-type Ca2+ channels were investigated. Experiments were performed using human islet cell clusters isolated from tissue of CHI patients (histologically classified as pathological) and islet cell clusters obtained from C57BL/6N (WT) or SUR1 knockout (SUR1-/-) mice. The cytosolic Ca2+ concentration ([Ca2+]c) was used as a parameter for the pathway regulated by electrical activity and was determined by fura-2 fluorescence. The mitochondrial membrane potential (ΔΨ) was determined by rhodamine 123 fluorescence and single channel currents were measured by the patch-clamp technique. RESULTS The selective KATP channel opener NN414 (5 µM) diminished [Ca2+]c in isolated human CHI islet cell clusters and WT mouse islet cell clusters stimulated with 10 mM glucose. In islet cell clusters lacking functional KATP channels (SUR1-/-) the drug was without effect. VU0071063 (30 µM), another KATP channel opener considered to be selective, lowered [Ca2+]c in human CHI islet cell clusters. The compound was also effective in islet cell clusters from SUR1-/- mice, showing that [Ca2+]c is influenced by additional effects besides KATP channels. Contrasting to NN414, the drug depolarized ΔΨ in murine islet cell clusters pointing to severe interference with mitochondrial metabolism. An opener of KCa3.1 channels, DCEBIO (100 µM), significantly decreased [Ca2+]c in SUR1-/- and human CHI islet cell clusters. To target L-type Ca2+ channels we tested two already approved drugs, dextromethorphan (DXM) and simvastatin. DXM (100 µM) efficiently diminished [Ca2+]c in stimulated human CHI islet cell clusters as well as in stimulated SUR1-/- islet cell clusters. Similar effects on [Ca2+]c were observed in experiments with simvastatin (7.2 µM). CONCLUSIONS NN414 seems to provide a good alternative to the currently used KATP channel opener diazoxide. Targeting KCa3.1 channels by channel openers or L-type Ca2+ channels by DXM or simvastatin might be valuable approaches for treatment of CHI caused by mutations of KATP channels not sensitive to KATP channel openers.
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Affiliation(s)
- Jelena Sikimic
- Department of Pharmacology, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Theresa Hoffmeister
- Department of Pharmacology, Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Münster, Germany
| | - Anne Gresch
- Department of Pharmacology, Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Münster, Germany
| | - Julia Kaiser
- Department of Pharmacology, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Winfried Barthlen
- Department of Pediatric Surgery, University Medicine Greifswald, Greifswald, Germany
| | - Carmen Wolke
- Institute of Medical Biochemistry and Molecular Biology, University Medicine Greifswald, Greifswald, Germany
| | - Ilse Wieland
- Institute of Human Genetics, University Hospital Magdeburg, Magdeburg, Germany
| | - Uwe Lendeckel
- Institute of Medical Biochemistry and Molecular Biology, University Medicine Greifswald, Greifswald, Germany
| | - Peter Krippeit-Drews
- Department of Pharmacology, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
- *Correspondence: Peter Krippeit-Drews,
| | - Martina Düfer
- Department of Pharmacology, Institute of Pharmaceutical and Medicinal Chemistry, University of Münster, Münster, Germany
| | - Gisela Drews
- Department of Pharmacology, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
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19
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Rosenfeld E, Ganguly A, De León DD. Congenital hyperinsulinism disorders: Genetic and clinical characteristics. AMERICAN JOURNAL OF MEDICAL GENETICS. PART C, SEMINARS IN MEDICAL GENETICS 2019; 181:682-692. [PMID: 31414570 PMCID: PMC7229866 DOI: 10.1002/ajmg.c.31737] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Revised: 07/13/2019] [Accepted: 07/29/2019] [Indexed: 12/11/2022]
Abstract
Congenital hyperinsulinism (HI) is the most frequent cause of persistent hypoglycemia in infants and children. Delays in diagnosis and initiation of appropriate treatment contribute to a high risk of neurocognitive impairment. HI represents a heterogeneous group of disorders characterized by dysregulated insulin secretion by the pancreatic beta cells, which in utero, may result in somatic overgrowth. There are at least nine known monogenic forms of HI as well as several syndromic forms. Molecular diagnosis allows for prediction of responsiveness to medical treatment and likelihood of surgically-curable focal hyperinsulinism. Timely genetic mutation analysis has thus become standard of care. However, despite significant advances in our understanding of the molecular basis of this disorder, the number of patients without an identified genetic diagnosis remains high, suggesting that there are likely additional genetic loci that have yet to be discovered.
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Affiliation(s)
- Elizabeth Rosenfeld
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Arupa Ganguly
- Department of Genetics, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Diva D. De León
- Division of Endocrinology and Diabetes, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
- Department of Pediatrics, The Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania, USA
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Boodhansingh KE, Kandasamy B, Mitteer L, Givler S, De Leon DD, Shyng S, Ganguly A, Stanley CA. Novel dominant K ATP channel mutations in infants with congenital hyperinsulinism: Validation by in vitro expression studies and in vivo carrier phenotyping. Am J Med Genet A 2019; 179:2214-2227. [PMID: 31464105 PMCID: PMC6852436 DOI: 10.1002/ajmg.a.61335] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 07/02/2019] [Accepted: 08/05/2019] [Indexed: 12/17/2022]
Abstract
Inactivating mutations in the genes encoding the two subunits of the pancreatic beta-cell KATP channel, ABCC8 and KCNJ11, are the most common finding in children with congenital hyperinsulinism (HI). Interpreting novel missense variants in these genes is problematic, because they can be either dominant or recessive mutations, benign polymorphisms, or diabetes mutations. This report describes six novel missense variants in ABCC8 and KCNJ11 that were identified in 11 probands with congenital HI. One of the three ABCC8 mutations (p.Ala1458Thr) and all three KCNJ11 mutations were associated with responsiveness to diazoxide. Sixteen family members carried the ABCC8 or KCNJ11 mutations; only two had hypoglycemia detected at birth and four others reported symptoms of hypoglycemia. Phenotype testing of seven adult mutation carriers revealed abnormal protein-induced hypoglycemia in all; fasting hypoketotic hypoglycemia was demonstrated in four of the seven. All of six mutations were confirmed to cause dominant pathogenic defects based on in vitro expression studies in COSm6 cells demonstrating normal trafficking, but reduced responses to MgADP and diazoxide. These results indicate a combination of in vitro and in vivo phenotype tests can be used to differentiate dominant from recessive KATP channel HI mutations and personalize management of children with congenital HI.
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Affiliation(s)
- Kara E. Boodhansingh
- Division of Endocrinology and DiabetesThe Children's Hospital of PhiladelphiaPhiladelphiaPennsylvania
| | - Balamurugan Kandasamy
- Department of Biochemistry and Molecular BiologyOregon Health & Science UniversityPortlandOregon
| | - Lauren Mitteer
- Division of Endocrinology and DiabetesThe Children's Hospital of PhiladelphiaPhiladelphiaPennsylvania
| | - Stephanie Givler
- Division of Endocrinology and DiabetesThe Children's Hospital of PhiladelphiaPhiladelphiaPennsylvania
| | - Diva D. De Leon
- Division of Endocrinology and DiabetesThe Children's Hospital of PhiladelphiaPhiladelphiaPennsylvania
- Department of PediatricsPerelman School of Medicine at the University of PennsylvaniaPhiladelphiaPennsylvania
| | - Show‐Ling Shyng
- Department of Biochemistry and Molecular BiologyOregon Health & Science UniversityPortlandOregon
| | - Arupa Ganguly
- Department of GeneticsThe Perelman School of Medicine at the University of PennsylvaniaPhiladelphiaPennsylvania
| | - Charles A. Stanley
- Division of Endocrinology and DiabetesThe Children's Hospital of PhiladelphiaPhiladelphiaPennsylvania
- Department of PediatricsPerelman School of Medicine at the University of PennsylvaniaPhiladelphiaPennsylvania
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21
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Leptin-induced Trafficking of K ATP Channels: A Mechanism to Regulate Pancreatic β-cell Excitability and Insulin Secretion. Int J Mol Sci 2019; 20:ijms20112660. [PMID: 31151172 PMCID: PMC6600549 DOI: 10.3390/ijms20112660] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 05/25/2019] [Accepted: 05/27/2019] [Indexed: 11/17/2022] Open
Abstract
The adipocyte hormone leptin was first recognized for its actions in the central nervous system to regulate energy homeostasis but has since been shown to have direct actions on peripheral tissues. In pancreatic β-cells leptin suppresses insulin secretion by increasing KATP channel conductance, which causes membrane hyperpolarization and renders β-cells electrically silent. However, the mechanism by which leptin increases KATP channel conductance had remained unresolved for many years following the initial observation. Recent studies have revealed that leptin increases surface abundance of KATP channels by promoting channel trafficking to the β-cell membrane. Thus, KATP channel trafficking regulation has emerged as a mechanism by which leptin increases KATP channel conductance to regulate β-cell electrical activity and insulin secretion. This review will discuss the leptin signaling pathway that underlies KATP channel trafficking regulation in β-cells.
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Ion Transporters, Channelopathies, and Glucose Disorders. Int J Mol Sci 2019; 20:ijms20102590. [PMID: 31137773 PMCID: PMC6566632 DOI: 10.3390/ijms20102590] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 05/21/2019] [Accepted: 05/22/2019] [Indexed: 01/19/2023] Open
Abstract
Ion channels and transporters play essential roles in excitable cells including cardiac, skeletal and smooth muscle cells, neurons, and endocrine cells. In pancreatic beta-cells, for example, potassium KATP channels link the metabolic signals generated inside the cell to changes in the beta-cell membrane potential, and ultimately regulate insulin secretion. Mutations in the genes encoding some ion transporter and channel proteins lead to disorders of glucose homeostasis (hyperinsulinaemic hypoglycaemia and different forms of diabetes mellitus). Pancreatic KATP, Non-KATP, and some calcium channelopathies and MCT1 transporter defects can lead to various forms of hyperinsulinaemic hypoglycaemia (HH). Mutations in the genes encoding the pancreatic KATP channels can also lead to different types of diabetes (including neonatal diabetes mellitus (NDM) and Maturity Onset Diabetes of the Young, MODY), and defects in the solute carrier family 2 member 2 (SLC2A2) leads to diabetes mellitus as part of the Fanconi–Bickel syndrome. Variants or polymorphisms in some ion channel genes and transporters have been reported in association with type 2 diabetes mellitus.
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Galcheva S, Demirbilek H, Al-Khawaga S, Hussain K. The Genetic and Molecular Mechanisms of Congenital Hyperinsulinism. Front Endocrinol (Lausanne) 2019; 10:111. [PMID: 30873120 PMCID: PMC6401612 DOI: 10.3389/fendo.2019.00111] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 02/06/2019] [Indexed: 12/13/2022] Open
Abstract
Congenital hyperinsulinism (CHI) is a heterogenous and complex disorder in which the unregulated insulin secretion from pancreatic beta-cells leads to hyperinsulinaemic hypoglycaemia. The severity of hypoglycaemia varies depending on the underlying molecular mechanism and genetic defects. The genetic and molecular causes of CHI include defects in pivotal pathways regulating the secretion of insulin from the beta-cell. Broadly these genetic defects leading to unregulated insulin secretion can be grouped into four main categories. The first group consists of defects in the pancreatic KATP channel genes (ABCC8 and KCNJ11). The second and third categories of conditions are enzymatic defects (such as GDH, GCK, HADH) and defects in transcription factors (for example HNF1α, HNF4α) leading to changes in nutrient flux into metabolic pathways which converge on insulin secretion. Lastly, a large number of genetic syndromes are now linked to hyperinsulinaemic hypoglycaemia. As the molecular and genetic basis of CHI has expanded over the last few years, this review aims to provide an up-to-date knowledge on the genetic causes of CHI.
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Affiliation(s)
- Sonya Galcheva
- Department of Paediatrics, University Hospital St. Marina, Varna Medical University, Varna, Bulgaria
| | - Hüseyin Demirbilek
- Department of Paediatric Endocrinology, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Sara Al-Khawaga
- Division of Endocrinology, Department of Paediatric Medicine, Sidra Medicine, Doha, Qatar
| | - Khalid Hussain
- Division of Endocrinology, Department of Paediatric Medicine, Sidra Medicine, Doha, Qatar
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24
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Xu ZD, Zhang W, Liu M, Wang HM, Hui PP, Liang XJ, Yan J, Wu YJ, Sang YM, Zhu C, Ni GC. Analysis on the pathogenic genes of 60 Chinese children with congenital hyperinsulinemia. Endocr Connect 2018; 7:1251-1261. [PMID: 30352420 PMCID: PMC6240136 DOI: 10.1530/ec-18-0240] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 10/05/2018] [Indexed: 02/01/2023]
Abstract
This study aims to summarize and analyze the clinical manifestations, genetic characteristics, treatment modalities and long-term prognosis of congenital hyperinsulinemia (CHI) in Chinese children. Sixty children with CHI, who were treated at Beijing Children's Hospital from January 2014 to August 2017, and their families, were selected as subjects. The CHI-related causative genes in children were sequenced and analyzed using second-generation sequencing technology. Furthermore, the genetic pathogenesis and clinical characteristics of Chinese children with CHI were explored. Among the 60 CHI children, 27 children (27/60, 45%) carried known CHI-related gene mutations: 16 children (26.7%) carried ABCC8 gene mutations, seven children (11.7%) carried GLUD1 gene mutations, one child carried GCK gene mutations, two children carried HNF4α gene mutations and one child carried HADH gene mutations. In these 60 patients, 8 patients underwent 18F-L-DOPA PET scan for the pancreas, and five children were found to be focal type. The treatment of diazoxide was ineffective in these five patients, and hypoglycemia could be controlled after receiving partial pancreatectomy. Conclusions: ABCC8 gene mutation is the most common cause of CHI in Chinese children. The early genetic analysis of children's families has an important guiding significance for treatment planning and prognosis assessment.
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Affiliation(s)
- Zi-Di Xu
- Department of Pediatric Endocrinology, Genetic and Metabolism, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Wei Zhang
- Department of Children Health Care, Xiamen Maternal and Child Health Hospital, Xiamen, China
| | - Min Liu
- Department of Pediatric Endocrinology, Genetic and Metabolism, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Huan-Min Wang
- Department of Surgical Oncology, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Pei-Pei Hui
- Department of Pediatric Endocrinology, Genetic and Metabolism, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Xue-Jun Liang
- Department of Pediatric Endocrinology, Genetic and Metabolism, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Jie Yan
- Department of Pediatric Endocrinology, Genetic and Metabolism, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Yu-Jun Wu
- Department of Pediatric Endocrinology, Genetic and Metabolism, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Yan-Mei Sang
- Department of Pediatric Endocrinology, Genetic and Metabolism, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
- Correspondence should be addressed to Y-M Sang:
| | - Cheng Zhu
- Department of Pediatric Endocrinology, Genetic and Metabolism, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
| | - Gui-Chen Ni
- Department of Pediatric Endocrinology, Genetic and Metabolism, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, Beijing, China
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Abstract
PURPOSE OF REVIEW Congenital hyperinsulinism is the most common cause of persistent hypoglycemia in infants and children. Early and appropriate recognition and treatment of hypoglycemia is vital to minimize neurocognitive impairment. RECENT FINDINGS There are at least 11 known monogenic forms of hyperinsulinism and several associated syndromes. Molecular diagnosis allows for prediction of the effectiveness of diazoxide and the likelihood of focal hyperinsulinism. Inactivating mutations in the genes encoding the ATP-sensitive potassium channel (KATP hyperinsulinism) account for 60% of all identifiable mutations, including 85% of diazoxide-unresponsive cases. Syndromes or disorders associated with hyperinsulinism include Beckwith-Wiedemann syndrome, Kabuki syndrome, Turner syndrome, and congenital disorders of glycosylation. Although focal hyperinsulinism can be cured by resection of the lesion, therapeutic options for nonfocal hyperinsulinism remain limited and include diazoxide, octreotide, long-acting somatostatin analogs, and near-total pancreatectomy. Although sirolimus has been reported to improve glycemic control in infants with diazoxide-unresponsive hyperinsulinism, the extent of improvement has been limited, and significant adverse events have been reported. SUMMARY Identification of the cause of congenital hyperinsulinism helps guide management decisions. Use of therapies with limited benefit and significant potential risks should be avoided.
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Huerta-Saenz L, Saunders C, Yan Y. Challenging diagnosis of congenital hyperinsulinism in two infants of diabetic mothers with rare pathogenic KCNJ11 and HNF4A gene variants. INTERNATIONAL JOURNAL OF PEDIATRIC ENDOCRINOLOGY 2018; 2018:5. [PMID: 30026763 PMCID: PMC6050669 DOI: 10.1186/s13633-018-0060-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Accepted: 07/09/2018] [Indexed: 01/29/2023]
Abstract
Background Congenital hyperinsulinism (CHI) is the leading cause of persistent hypoglycemia in infants. The infants of diabetic mothers (IDMs) very frequently present with neonatal hypoglycemia associated to transient hyperinsulinism however the incidence of CHI in IDMs is unknown. Case presentation Here we report 2 cases of CHI where the diagnoses were challenged and delayed because both patients were infants of diabetic mothers (IDMs) and had concomitant complicated medical conditions. Case 1 was heterozygous for a likely pathogenic variant in KCNJ11(p.Arg206Cys), and Case 2 was heterozygous for a pathogenic HNF4A variant, (p.Arg267Cys). HNF4A-associated CHI is very rare, and this particular case had a clinical phenotype quite different from that of previously described HNF4A-CHI cases. Conclusions This case series is one of few reports in the medical literature describing two IDMs with persistent recurrent hypoglycemia secondary to CHI, and a different clinical phenotype for HNF4A-associated CHI. IDMs typically present with transient hyperinsulinism lasting no more than 2–3 days. Since being an IDM does not exclude CHI, this diagnosis should always be considered as the mostly likely etiology if neonatal hypoglycemia persists longer than the described time frame and genetic testing for CHI confirmation is highly suggested.
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Affiliation(s)
- Lina Huerta-Saenz
- 1Children's Mercy Kansas City, Division of Pediatric Endocrinology, 3101 Broadway Blvd, Kansas City, MO 64111 USA.,Children's Mercy- Wichita Specialty Clinic, Wichita, KS USA.,3University of Missouri-Kansas City, Kansas City, MO USA.,4University of Kansas Medical Center-Wichita School of Medicine, Wichita, KS USA.,7Present address: Penn State College of Medicine, Penn State Children's Hospital- Division of Pediatric Endocrinology and Diabetes, Hershey, PA USA
| | - Carol Saunders
- 3University of Missouri-Kansas City, Kansas City, MO USA.,5Center for Pediatric Genomic Medicine Children's Mercy Hospital, Kansas City, MO USA.,6Department of Pathology and Laboratory Medicine, Children's Mercy Hospital, Kansas City, MO USA
| | - Yun Yan
- 1Children's Mercy Kansas City, Division of Pediatric Endocrinology, 3101 Broadway Blvd, Kansas City, MO 64111 USA.,Children's Mercy- Wichita Specialty Clinic, Wichita, KS USA.,3University of Missouri-Kansas City, Kansas City, MO USA
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27
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Rozenkova K, Nessa A, Obermannova B, Elblova L, Dusatkova P, Sumnik Z, Lebl J, Hussain K, Pruhova S. Could a combination of heterozygous ABCC8 and KCNJ11 mutations cause congenital hyperinsulinism? J Pediatr Endocrinol Metab 2017; 30:1311-1315. [PMID: 29127764 DOI: 10.1515/jpem-2017-0163] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 09/28/2017] [Indexed: 11/15/2022]
Abstract
BACKGROUND Congenital hyperinsulinism (CHI) is frequently caused by mutations in one of the KATP channel subunits encoded by the genes ABCC8 and KCNJ11. The effect of simultaneous mutations in both of these genes on the pancreatic β-cell function is not known and patients with CHI carrying both ABCC8 and KCNJ11 mutations have not yet been reported. We questioned if a combination of heterozygous mutations in the ABCC8 and KCNJ11 genes could also lead to β-cell dysfunction presenting as CHI. METHODS As a model, we used a patient with transient CHI that paternally inherited novel heterozygous mutations in ABCC8 (p.Tyr1293Asp) and KCNJ11 (p.Arg50Trp) genes. The pathogenic effects on the pancreatic β-cells function were examined in an in vitro functional study using radioactive rubidium efflux assay. RESULTS We showed that the activation of the mutated KATP channels by diazoxide was decreased by 60.9% in the channels with the heterozygous combination of both mutations compared to the wild type channels. This could indicate the pathogenic effect on the pancreatic β-cell function leading to CHI although conclusive evidence is needed to be added. CONCLUSIONS Our findings may widen the spectrum of genetic causes of CHI and suggest a novel pathogenic mechanism of CHI that must however, be further investigated.
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28
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Martin GM, Rex EA, Devaraneni P, Denton JS, Boodhansingh KE, DeLeon DD, Stanley CA, Shyng SL. Pharmacological Correction of Trafficking Defects in ATP-sensitive Potassium Channels Caused by Sulfonylurea Receptor 1 Mutations. J Biol Chem 2016; 291:21971-21983. [PMID: 27573238 DOI: 10.1074/jbc.m116.749366] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Indexed: 11/06/2022] Open
Abstract
ATP-sensitive potassium (KATP) channels play a key role in mediating glucose-stimulated insulin secretion by coupling metabolic signals to β-cell membrane potential. Loss of KATP channel function due to mutations in ABCC8 or KCNJ11, genes encoding the sulfonylurea receptor 1 (SUR1) or the inwardly rectifying potassium channel Kir6.2, respectively, results in congenital hyperinsulinism. Many SUR1 mutations prevent trafficking of channel proteins from the endoplasmic reticulum to the cell surface. Channel inhibitors, including sulfonylureas and carbamazepine, have been shown to correct channel trafficking defects. In the present study, we identified 13 novel SUR1 mutations that cause channel trafficking defects, the majority of which are amenable to pharmacological rescue by glibenclamide and carbamazepine. By contrast, none of the mutant channels were rescued by KATP channel openers. Cross-linking experiments showed that KATP channel inhibitors promoted interactions between the N terminus of Kir6.2 and SUR1, whereas channel openers did not, suggesting the inhibitors enhance intersubunit interactions to overcome channel biogenesis and trafficking defects. Functional studies of rescued mutant channels indicate that most mutants rescued to the cell surface exhibited WT-like sensitivity to ATP, MgADP, and diazoxide. In intact cells, recovery of channel function upon trafficking rescue by reversible sulfonylureas or carbamazepine was facilitated by the KATP channel opener diazoxide. Our study expands the list of KATP channel trafficking mutations whose function can be recovered by pharmacological ligands and provides further insight into the structural mechanism by which channel inhibitors correct channel biogenesis and trafficking defects.
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Affiliation(s)
- Gregory M Martin
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239
| | - Emily A Rex
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239
| | - Prasanna Devaraneni
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239
| | - Jerod S Denton
- the Department of Anesthesiology, Vanderbilt University, Nashville, Tennessee 37232, and
| | - Kara E Boodhansingh
- the Division of Endocrinology/Diabetes, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Diva D DeLeon
- the Division of Endocrinology/Diabetes, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Charles A Stanley
- the Division of Endocrinology/Diabetes, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Show-Ling Shyng
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239,
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29
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Güven A, Cebeci AN, Ellard S, Flanagan SE. Clinical and Genetic Characteristics, Management and Long-Term Follow-Up of Turkish Patients with Congenital Hyperinsulinism. J Clin Res Pediatr Endocrinol 2016; 8:197-204. [PMID: 26758964 PMCID: PMC5096476 DOI: 10.4274/jcrpe.2408] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVE Mutations in the KATP channel genes is the most common cause of congenital hyperinsulinism (CHI) of infancy. Our aim was to report the clinical and genetic characteristics, treatment modalities, and long-term prognosis of patients with CHI. METHODS Clinical and biochemical findings, operation procedures, and results of genetic analysis were retrospectively evaluated in 22 CHI patients from two pediatric endocrine centers in Turkey. RESULTS Seven of the patients were born large for gestational age. Hypoglycemia was diagnosed within the first 24 hours of life in 9 patients and treatment with diazoxide (n=21) and/or somatostatin (n=8) had been attempted. Seven patients (31.8%) were unresponsive to medical treatment and underwent pancreatectomy. Histological examination of the pancreas confirmed diffuse disease in 6 patients. Diabetes developed in 3 patients following pancreatectomy (10 years, 2.5 years, and immediately after operation). The remaining four patients had neither recurrence of CHI nor of diabetes during the 3.67±0.7 years of follow-up. Sequence analysis identified mutations in 12 out of 19 patients (63%). Mutations in the ABCC8 gene were the most common finding and were found in 6 out of 7 patients who underwent pancreatectomy. Other mutations included a paternally inherited KCNJ11 mutation, a homozygous HADH mutation, and a heterozygous GLUD1 mutation. CONCLUSION Mutations in the ABCC8 gene were the most common cause of CHI in our cohort. These mutations were identified in 85% of patients who underwent pancreatectomy. The development of diabetes mellitus after pancreatectomy may occur at any age and these patients should be screened regularly.
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Affiliation(s)
- Ayla Güven
- Göztepe Training and Research Hospital, Clinic of Pediatric Endocrinology, İstanbul, Turkey, E-mail:
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30
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Martínez R, Fernández-Ramos C, Vela A, Velayos T, Aguayo A, Urrutia I, Rica I, Castaño L. Clinical and genetic characterization of congenital hyperinsulinism in Spain. Eur J Endocrinol 2016; 174:717-26. [PMID: 27188453 DOI: 10.1530/eje-16-0027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 03/07/2016] [Indexed: 12/30/2022]
Abstract
CONTEXT Congenital hyperinsulinism (CHI) is a clinically and genetically heterogeneous disease characterized by severe hypoglycemia caused by inappropriate insulin secretion by pancreatic β-cells. OBJECTIVE To characterize clinically and genetically CHI patients in Spain. DESIGN AND METHODS We included 50 patients with CHI from Spain. Clinical information was provided by the referring clinicians. Mutational analysis was carried out for KCNJ11, ABCC8, and GCK genes. The GLUD1, HNF4A, HNF1A, UCP2, and HADH genes were sequenced depending on the clinical phenotype. RESULTS We identified the genetic etiology in 28 of the 50 CHI patients tested: 21 had a mutation in KATP channel genes (42%), three in GLUD1 (6%), and four in GCK (8%). Most mutations were found in ABCC8 (20/50). Half of these patients (10/20) were homozygous or compound heterozygous, with nine being unresponsive to diazoxide treatment. The other half had heterozygous mutations in ABCC8, six of them being unresponsive to diazoxide treatment and four being responsive to diazoxide treatment. We identified 22 different mutations in the KATP channel genes, of which ten were novel. Notably, patients with ABCC8 mutations were diagnosed earlier, with lower blood glucose levels and required higher doses of diazoxide than those without a genetic diagnosis. CONCLUSIONS Genetic analysis revealed mutations in 56% of the CHI patients. ABCC8 mutations are the most frequent cause of CHI in Spain. We found ten novel mutations in the KATP channel genes. The genetic diagnosis is more likely to be achieved in patients with onset within the first week of life and in those who fail to respond to diazoxide treatment.
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Affiliation(s)
- R Martínez
- Endocrinology and Diabetes Research GroupBioCruces Health Research Institute, Cruces University Hospital, CIBERDEM, CIBERER, UPV-EHU, Barakaldo, Spain
| | - C Fernández-Ramos
- Pediatric Endocrinology SectionBasurto University Hospital, BioCruces Health Research Institute, UPV/EHU, Bilbao, Spain
| | - A Vela
- Pediatric Endocrinology SectionCruces University Hospital, BioCruces Health Research Institute, CIBERDEM, CIBERER, UPV/EHU, Barakaldo, Spain
| | - T Velayos
- Endocrinology and Diabetes Research GroupBioCruces Health Research Institute, Cruces University Hospital, CIBERDEM, CIBERER, UPV-EHU, Barakaldo, Spain
| | - A Aguayo
- Endocrinology and Diabetes Research GroupBioCruces Health Research Institute, Cruces University Hospital, CIBERDEM, CIBERER, UPV-EHU, Barakaldo, Spain
| | - I Urrutia
- Endocrinology and Diabetes Research GroupBioCruces Health Research Institute, Cruces University Hospital, CIBERDEM, CIBERER, UPV-EHU, Barakaldo, Spain
| | - I Rica
- Pediatric Endocrinology SectionCruces University Hospital, BioCruces Health Research Institute, CIBERDEM, CIBERER, UPV/EHU, Barakaldo, Spain
| | - L Castaño
- Endocrinology and Diabetes Research GroupBioCruces Health Research Institute, Cruces University Hospital, CIBERDEM, CIBERER, UPV-EHU, Barakaldo, Spain
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31
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Abstract
CONTEXT Congenital hyperinsulinism (HI) is the most common cause of hypoglycemia in children. The risk of permanent brain injury in infants with HI continues to be as high as 25-50% due to delays in diagnosis and inadequate treatment. Congenital HI has been described since the birth of the JCEM under various terms, including "idiopathic hypoglycemia of infancy," "leucine-sensitive hypoglycemia," or "nesidioblastosis." EVIDENCE ACQUISITION In the past 20 years, it has become apparent that HI is caused by genetic defects in the pathways that regulate pancreatic β-cell insulin secretion. EVIDENCE SYNTHESIS There are now 11 genes associated with monogenic forms of HI (ABCC8, KCNJ11, GLUD1, GCK, HADH1, UCP2, MCT1, HNF4A, HNF1A, HK1, PGM1), as well as several syndromic genetic forms of HI (eg, Beckwith-Wiedemann, Kabuki, and Turner syndromes). HI is also the cause of hypoglycemia in transitional neonatal hypoglycemia and in persistent hypoglycemia in various groups of high-risk neonates (such as birth asphyxia, small for gestational age birthweight, infant of diabetic mother). Management of HI is one of the most difficult problems faced by pediatric endocrinologists and frequently requires difficult choices, such as near-total pancreatectomy and/or highly intensive care with continuous tube feedings. For 50 years, diazoxide, a KATP channel agonist, has been the primary drug for infants with HI; however, it is ineffective in most cases with mutations of ABCC8 or KCNJ11, which constitute the majority of infants with monogenic HI. CONCLUSIONS Genetic mutation testing has become standard of care for infants with HI and has proven to be useful not only in projecting prognosis and family counseling, but also in diagnosing infants with surgically curable focal HI lesions. (18)F-fluoro-L-dihydroxyphenylalanine ((18)F-DOPA) PET scans have been found to be highly accurate for localizing such focal lesions preoperatively. New drugs under investigation provide hope for improving the outcomes of children with HI.
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Affiliation(s)
- Charles A Stanley
- Division of Endocrinology, The Children's Hospital of Philadelphia, Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104
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32
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Nessa A, Rahman SA, Hussain K. Hyperinsulinemic Hypoglycemia - The Molecular Mechanisms. Front Endocrinol (Lausanne) 2016; 7:29. [PMID: 27065949 PMCID: PMC4815176 DOI: 10.3389/fendo.2016.00029] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 03/21/2016] [Indexed: 12/14/2022] Open
Abstract
Under normal physiological conditions, pancreatic β-cells secrete insulin to maintain fasting blood glucose levels in the range 3.5-5.5 mmol/L. In hyperinsulinemic hypoglycemia (HH), this precise regulation of insulin secretion is perturbed so that insulin continues to be secreted in the presence of hypoglycemia. HH may be due to genetic causes (congenital) or secondary to certain risk factors. The molecular mechanisms leading to HH involve defects in the key genes regulating insulin secretion from the β-cells. At this moment, in time genetic abnormalities in nine genes (ABCC8, KCNJ11, GCK, SCHAD, GLUD1, SLC16A1, HNF1A, HNF4A, and UCP2) have been described that lead to the congenital forms of HH. Perinatal stress, intrauterine growth retardation, maternal diabetes mellitus, and a large number of developmental syndromes are also associated with HH in the neonatal period. In older children and adult's insulinoma, non-insulinoma pancreatogenous hypoglycemia syndrome and post bariatric surgery are recognized causes of HH. This review article will focus mainly on describing the molecular mechanisms that lead to unregulated insulin secretion.
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Affiliation(s)
- Azizun Nessa
- Genetics and Genomic Medicine Programme, Department of Paediatric Endocrinology, UCL Institute of Child Health, Great Ormond Street Hospital for Children NHS, London, UK
| | - Sofia A. Rahman
- Genetics and Genomic Medicine Programme, Department of Paediatric Endocrinology, UCL Institute of Child Health, Great Ormond Street Hospital for Children NHS, London, UK
| | - Khalid Hussain
- Genetics and Genomic Medicine Programme, Department of Paediatric Endocrinology, UCL Institute of Child Health, Great Ormond Street Hospital for Children NHS, London, UK
- *Correspondence: Khalid Hussain,
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Soheilipour F, Jesmi F, Ahmadi M, Pazouki A, Alibeigi P, Abdolhosseini M. Minimally invasive surgical interventions in the treatment of primary persistent hyperinsulinemic hypoglycemia of infancy. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2015; 59:466-9. [PMID: 26331229 DOI: 10.1590/2359-3997000000094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 04/20/2015] [Indexed: 11/22/2022]
Abstract
Hyperinsulinemia, diagnosed by laboratory tests, should be diagnosed and treated as soon as possible to prevent fatal complications such as neurological damage. Patients who are resistant to medical therapy should be treated surgically. Minimally invasive surgery, a newly developed approach, is a good choice among surgical procedures to avoid unnecessary extensive pancreatectomy. Here, a 12-year-old boy is presented with diagnosis of hyperinsulinemic hypoglycemia who had recurrent attacks of hypoglycemia and seizures from infancy. Because of his unresponsiveness to medical therapy and his family's preference, he underwent laparoscopic pancreatectomy to reduce morbidity and hospital stay. Two years postsurgical follow-up revealed a normo-glycemic state.
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Affiliation(s)
- Fahimeh Soheilipour
- Minimally Invasive Surgery Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Jesmi
- Minimally Invasive Surgery Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Ahmadi
- Minimally Invasive Surgery Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Abdolreza Pazouki
- Minimally Invasive Surgery Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Peyman Alibeigi
- Minimally Invasive Surgery Research Center, Iran University of Medical Sciences, Tehran, Iran
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Nessa A, Aziz QH, Thomas AM, Harmer SC, Tinker A, Hussain K. Molecular mechanisms of congenital hyperinsulinism due to autosomal dominant mutations in ABCC8. Hum Mol Genet 2015; 24:5142-53. [PMID: 26092864 DOI: 10.1093/hmg/ddv233] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 06/16/2015] [Indexed: 11/12/2022] Open
Abstract
Congenital Hyperinsulinism (CHI) is a rare heterogeneous disease characterized by unregulated insulin secretion. Dominant mutations in ABCC8 causing medically unresponsive CHI have been reported; however, the molecular mechanisms are not clear. The molecular basis of medically unresponsive CHI due to dominant ABCC8 mutations has been studied in 10 patients, who were medically unresponsive to diazoxide (DZX), and nine of whom required a near-total pancreatectomy, and one partial pancreatectomy. DNA sequencing revealed seven dominant inactivating heterozygous missense mutations in ABCC8, including one novel and six previously reported but uncharacterized mutations. Two groups of mutations with different cellular mechanisms were characterized. Mutations in the transmembrane domain (TMD) were more responsive to channel activators such as DZX, MgADP and metabolic inhibition. The trafficking analysis has shown that nucleotide-binding domain two (NBD2) mutations are not retained in the endoplasmic reticulum (ER) and are present on the membrane. However, the TMD mutations were retained in the ER. D1506E was the most severe SUR1-NBD2 mutation. Homologous expression of D1506E revealed a near absence of KATP currents in the presence of DZX and intracellular MgADP. Heterozygous expression of D1506E showed a strong dominant-negative effect on SUR1\Kir6.2 currents. Overall, we define two groups of mutation with different cellular mechanisms. In the first group, channel complexes with mutations in NBD2 of SUR1 traffic normally but are unable to be activated by MgADP. In the second group, channels mutations in the TMD of SUR1 are retained in the ER and have variable functional impairment.
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Affiliation(s)
- Azizun Nessa
- Genetics and Genomic Medicine, UCL Institute of Child Health, London WC1N 1EH, UK
| | - Qadeer H Aziz
- The Heart Centre, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK and
| | - Alison M Thomas
- The Heart Centre, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK and
| | - Stephen C Harmer
- The Heart Centre, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK and
| | - Andrew Tinker
- The Heart Centre, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK and
| | - Khalid Hussain
- Genetics and Genomic Medicine, UCL Institute of Child Health, London WC1N 1EH, UK, Genetics and Genomic Medicine, UCL Institute of Child Health, London Centre for Paediatric Endocrinology and Metabolism, Great Ormond Street Hospital for Children NHS, London WC1N 1EH, UK
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Roženková K, Güemes M, Shah P, Hussain K. The Diagnosis and Management of Hyperinsulinaemic Hypoglycaemia. J Clin Res Pediatr Endocrinol 2015; 7:86-97. [PMID: 26316429 PMCID: PMC4563192 DOI: 10.4274/jcrpe.1891] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Insulin secretion from pancreatic β-cells is tightly regulated to keep fasting blood glucose concentrations within the normal range (3.5-5.5 mmol/L). Hyperinsulinaemic hypoglycaemia (HH) is a heterozygous condition in which insulin secretion becomes unregulated and its production persists despite low blood glucose levels. It is the most common cause of severe and persistent hypoglycaemia in neonates and children. The most severe and permanent forms are due to congenital hyperinsulinism (CHI). Recent advances in genetics have linked CHI to mutations in 9 genes that play a key role in regulating insulin secretion (ABCC8, KCNJ11, GLUD1, GCK, HADH, SLC16A1, UCP2, HNF4A and HNF1A). Histologically, CHI can be divided into 3 types; diffuse, focal and atypical. Given the biochemical nature of HH (non-ketotic), a delay in the diagnosis and management can result in irreversible brain damage. Therefore, it is essential to diagnose and treat HH promptly. Advances in molecular genetics, imaging methods (18F-DOPA PET-CT), medical therapy and surgical approach (laparoscopic surgery) have completely changed the management and improved the outcome of these children. This review provides an overview of the genetic and molecular mechanisms leading to development of HH in children. The article summarizes the current diagnostic methods and management strategies for the different types of CHI.
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Affiliation(s)
| | | | | | - Khalid Hussain
- Great Ormond Street Hospital for Children, UCL Institute of Child Health, Genetics and Epigenetics in Health and Disease, Genetics and Genomic Medicine Programme, London, UK Phone: +44 2079052128 E-mail:
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Abstract
Congenital hyperinsulinism (CHI) is a complex heterogeneous condition in which insulin secretion from pancreatic β-cells is unregulated and inappropriate for the level of blood glucose. The inappropriate insulin secretion drives glucose into the insulin-sensitive tissues, such as the muscle, liver and adipose tissue, leading to severe hyperinsulinaemic hypoglycaemia (HH). At a molecular level, genetic abnormalities in nine different genes (ABCC8, KCNJ11, GLUD1, GCK, HNF4A, HNF1A, SLC16A1, UCP2 and HADH) have been identified which cause CHI. Autosomal recessive and dominant mutations in ABCC8/KCNJ11 are the commonest cause of medically unresponsive CHI. Mutations in GLUD1 and HADH lead to leucine-induced HH, and these two genes encode the key enzymes glutamate dehydrogenase and short chain 3-hydroxyacyl-CoA dehydrogenase which play a key role in amino acid and fatty acid regulation of insulin secretion respectively. Genetic abnormalities in HNF4A and HNF1A lead to a dual phenotype of HH in the newborn period and maturity onset-diabetes later in life. This state of the art review provides an update on the molecular basis of CHI.
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Affiliation(s)
- Sofia A Rahman
- Genetics and Genomic MedicineUCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UKDepartment of Paediatric EndocrinologyGreat Ormond Street Hospital for Children NHS, 30 Guilford Street, London WC1N 1EH, UK
| | - Azizun Nessa
- Genetics and Genomic MedicineUCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UKDepartment of Paediatric EndocrinologyGreat Ormond Street Hospital for Children NHS, 30 Guilford Street, London WC1N 1EH, UK
| | - Khalid Hussain
- Genetics and Genomic MedicineUCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UKDepartment of Paediatric EndocrinologyGreat Ormond Street Hospital for Children NHS, 30 Guilford Street, London WC1N 1EH, UK Genetics and Genomic MedicineUCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UKDepartment of Paediatric EndocrinologyGreat Ormond Street Hospital for Children NHS, 30 Guilford Street, London WC1N 1EH, UK
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Bennett JT, Vasta V, Zhang M, Narayanan J, Gerrits P, Hahn SH. Molecular genetic testing of patients with monogenic diabetes and hyperinsulinism. Mol Genet Metab 2015; 114:451-8. [PMID: 25555642 PMCID: PMC7852340 DOI: 10.1016/j.ymgme.2014.12.304] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 12/13/2014] [Accepted: 12/13/2014] [Indexed: 02/06/2023]
Abstract
Genetic sequencing has become a critical part of the diagnosis of certain forms of pancreatic beta cell dysfunction. Despite great advances in the speed and cost of DNA sequencing, determining the pathogenicity of variants remains a challenge, and requires sharing of sequence and phenotypic data between laboratories. We reviewed all diabetes and hyperinsulinism-associated molecular testing done at the Seattle Children's Molecular Genetics Laboratory from 2009 to 2013. 331 probands were referred to us for molecular genetic sequencing for Neonatal Diabetes (NDM), Maturity-Onset Diabetes of the Young (MODY), or Congenital Hyperinsulinism (CHI) during this period. Reportable variants were identified in 115 (35%) patients with 91 variants in one of 6 genes: HNF1A, GCK, HNF4A, ABCC8, KCNJ11, or INS. In addition to identifying 23 novel variants, we identified unusual mechanisms of inheritance, including mosaic and digenic MODY presentations. Re-analysis of all reported variants using more recently available databases led to a change in variant interpretation from the original report in 30% of cases. These results represent a resource for molecular testing of monogenic forms of diabetes and hyperinsulinism, providing a mutation spectrum for these disorders in a large North American cohort. In addition, they highlight the importance of periodic review of molecular testing results.
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Affiliation(s)
- James T Bennett
- Department of Pediatrics, University of Washington School of Medicine, Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Valeria Vasta
- Department of Pediatrics, University of Washington School of Medicine, Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Min Zhang
- Department of Pediatrics, University of Washington School of Medicine, Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Jaya Narayanan
- Department of Pediatrics, University of Washington School of Medicine, Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Peter Gerrits
- Department of Pediatric Endocrinology, Beaumont Children's Hospital, Royal Oak, MI 48073, USA
| | - Si Houn Hahn
- Department of Pediatrics, University of Washington School of Medicine, Seattle Children's Hospital, Seattle, WA 98105, USA.
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Ortiz D, Bryan J. Neonatal Diabetes and Congenital Hyperinsulinism Caused by Mutations in ABCC8/SUR1 are Associated with Altered and Opposite Affinities for ATP and ADP. Front Endocrinol (Lausanne) 2015; 6:48. [PMID: 25926814 PMCID: PMC4397924 DOI: 10.3389/fendo.2015.00048] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 03/21/2015] [Indexed: 12/28/2022] Open
Abstract
ATP-sensitive K(+) (KATP) channels composed of potassium inward-rectifier type 6.2 and sulfonylurea receptor type 1 subunits (Kir6.2/SUR1)4 are expressed in various cells in the brain and endocrine pancreas where they couple metabolic status to membrane potential. In β-cells, increases in cytosolic [ATP/ADP]c inhibit KATP channel activity, leading to membrane depolarization and exocytosis of insulin granules. Mutations in ABCC8 (SUR1) or KCNJ11 (Kir6.2) can result in gain or loss of channel activity and cause neonatal diabetes (ND) or congenital hyperinsulinism (CHI), respectively. SUR1 is reported to be a Mg(2+)-dependent ATPase. A prevailing model posits that ATP hydrolysis at SUR1 is required to stimulate openings of the pore. However, recent work shows nucleotide binding, without hydrolysis, is sufficient to switch SUR1 to stimulatory conformations. The actions of nucleotides, ATP and ADP, on ND (SUR1E1506D) and CHI (SUR1E1506K) mutants, without Kir6.2, were compared to assess both models. Both substitutions significantly impair hydrolysis in SUR1 homologs. SUR1E1506D has greater affinity for MgATP than wildtype; SUR1E1506K has reduced affinity. Without Mg(2+), SUR1E1506K has a greater affinity for ATP(4-) consistent with electrostatic attraction between ATP(4-), unshielded by Mg(2+), and the basic lysine. Further analysis of ND and CHI ABCC8 mutants in the second transmembrane and nucleotide-binding domains (TMD2 and NBD2) found a relation between their affinities for ATP (±Mg(2+)) and their clinical phenotype. Increased affinity for ATP is associated with ND; decreased affinity with CHI. In contrast, MgADP showed a weaker relationship. Diazoxide, known to reduce insulin release in some CHI cases, potentiates switching of CHI mutants from non-stimulatory to stimulatory states consistent with diazoxide stabilizing a nucleotide-bound conformation. The results emphasize the greater importance of nucleotide binding vs. hydrolysis in the regulation of KATP channels in vivo.
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Affiliation(s)
- David Ortiz
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, USA
| | - Joseph Bryan
- Pacific Northwest Diabetes Research Institute, Seattle, WA, USA
- *Correspondence: Joseph Bryan, Pacific Northwest Diabetes Research Institute, 720 Broadway, Seattle, WA 98122, USA e-mail:
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Congenital hyperinsulinism: clinical and molecular characterisation of compound heterozygous ABCC8 mutation responsive to Diazoxide therapy. INTERNATIONAL JOURNAL OF PEDIATRIC ENDOCRINOLOGY 2014; 2014:24. [PMID: 25584046 PMCID: PMC4290134 DOI: 10.1186/1687-9856-2014-24] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 11/25/2014] [Indexed: 11/23/2022]
Abstract
Background Mutations in ABCC8 and KCNJ11 are the most common cause of congenital hyperinsulinism (CHI). Recessive as well as dominant acting ABCC8/KCNJ11 mutations have been described. Diazoxide, which is the first line medication for CHI, is usually ineffective in recessive ABCC8 mutations. We describe the clinical and molecular characterisation of a recessive ABCC8 mutation in a CHI patient that is diazoxide response. Clinical case A term macrosomic female infant presented with symptomatic persistent hypoglycaemia confirmed to be secondary to CHI. She exhibited an excellent response to moderate doses of diazoxide (10 mg/kg/day). Molecular genetic analysis of the proband confirmed a biallelic ABCC8 mutation – missense R526C inherited from an unaffected mother and a frameshift c.1879delC mutation (H627Mfs*20) inherited from an unaffected father. Follow-up highlighted persistent requirement for diazoxide to control CHI. Functional analysis of mutants confirmed them to result in diazoxide-responsive CHI, consistent with the clinical phenotype. Conclusion Biallelic ABCC8 mutations may result in diazoxide-responsive CHI. Irrespective of the molecular genetic analysis results, accurate assessment of the response to diazoxide should be undertaken before classifying a patient as diazoxide-responsive or unresponsive CHI.
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Arya VB, Guemes M, Nessa A, Alam S, Shah P, Gilbert C, Senniappan S, Flanagan SE, Ellard S, Hussain K. Clinical and histological heterogeneity of congenital hyperinsulinism due to paternally inherited heterozygous ABCC8/KCNJ11 mutations. Eur J Endocrinol 2014; 171:685-95. [PMID: 25201519 DOI: 10.1530/eje-14-0353] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
CONTEXT Congenital hyperinsulinism (CHI) has two main histological types: diffuse and focal. Heterozygous paternally inherited ABCC8/KCNJ11 mutations (depending upon whether recessive or dominant acting and occurrence of somatic maternal allele loss) can give rise to either phenotype. However, the relative proportion of these two phenotypes in a large cohort of CHI patients due to paternally inherited heterozygous ABCC8/KCNJ11 mutations has not been reported. OBJECTIVE The purpose of this study is to highlight the variable clinical phenotype and to characterise the distribution of diffuse and focal disease in a large cohort of CHI patients due to paternally inherited heterozygous ABCC8/KCNJ11 mutations. DESIGN A retrospective chart review of the CHI patients due to heterozygous paternally inherited ABCC8/KCNJ11 mutations from 2000 to 2013 was conducted. RESULTS Paternally inherited heterozygous ABCC8/KCNJ11 mutations were identified in 53 CHI patients. Of these, 18 (34%) either responded to diazoxide or resolved spontaneously. Fluorine-18 l-3, 4-dihydroxyphenylalanine positron emission tomography computerised tomography 18F DOPA-PET CT) scanning in 3/18 children showed diffuse disease. The remaining 35 (66%) diazoxide-unresponsive children either had pancreatic venous sampling (n=8) or 18F DOPA-PET CT (n=27). Diffuse, indeterminate and focal disease was identified in 13, 1 and 21 patients respectively. Two patients with suspected diffuse disease were identified to have focal disease on histology. CONCLUSIONS Paternally inherited heterozygous ABCC8/KCNJ11 mutations can manifest as a wide spectrum of CHI with variable 18F DOPA-PET CT/histological findings and clinical outcomes. Focal disease was histologically confirmed in 24/53 (45%) of CHI patients with paternally inherited heterozygous ABCC8/KCNJ11 mutations.
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Affiliation(s)
- Ved Bhushan Arya
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
| | - Maria Guemes
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
| | - Azizun Nessa
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
| | - Syeda Alam
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
| | - Pratik Shah
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
| | - Clare Gilbert
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
| | - Senthil Senniappan
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
| | - Sarah E Flanagan
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
| | - Sian Ellard
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
| | - Khalid Hussain
- Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK Developmental Endocrinology Research GroupClinical and Molecular Genetics Unit, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UKLondon Centre for Paediatric EndocrinologyGreat Ormond Street Hospital for Children, London WC1N 3JH, UKInstitute of Biomedical and Clinical ScienceUniversity of Exeter Medical School, Exeter EX2 5DW, UK
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Maiorana A, Barbetti F, Boiani A, Rufini V, Pizzoferro M, Francalanci P, Faletra F, Nichols CG, Grimaldi C, de Ville de Goyet J, Rahier J, Henquin JC, Dionisi-Vici C. Focal congenital hyperinsulinism managed by medical treatment: a diagnostic algorithm based on molecular genetic screening. Clin Endocrinol (Oxf) 2014; 81:679-88. [PMID: 24383515 DOI: 10.1111/cen.12400] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/18/2013] [Revised: 10/24/2013] [Accepted: 12/31/2013] [Indexed: 12/30/2022]
Abstract
OBJECTIVE Congenital hyperinsulinism (CHI) requires rapid diagnosis and treatment to avoid irreversible neurological sequelae due to hypoglycaemia. Aetiological diagnosis is instrumental in directing the appropriate therapy. Current diagnostic algorithms provide a complete set of diagnostic tools including (i) biochemical assays, (ii) genetic facility and (iii) state-of-the-art imaging. They consider the response to a therapeutic diazoxide trial an early, crucial step before proceeding (or not) to specific genetic testing and eventually imaging, aimed at distinguishing diffuse vs focal CHI. However, interpretation of the diazoxide test is not trivial and can vary between research groups, which may lead to inappropriate decisions. Objective of this report is proposing a new algorithm in which early genetic screening, rather than diazoxide trial, dictates subsequent clinical decisions. PATIENTS, METHODS AND RESULTS Two CHI patients weaned from parenteral glucose infusion and glucagon after starting diazoxide. No hypoglycaemia was registered during a 72-h continuous glucose monitoring (CGMS), or hypoglycaemic episodes were present for no longer than 3% of 72-h. Normoglycaemia was obtained by low-medium dose diazoxide combined with frequent carbohydrate feeds for several years. We identified monoallelic, paternally inherited mutations in KATP channel genes, and (18) F-DOPA PET-CT revealed a focal lesion that was surgically resected, resulting in complete remission of hypoglycaemia. CONCLUSIONS Although rare, some patients with focal lesions may be responsive to diazoxide. As a consequence, we propose an algorithm that is not based on a 'formal' diazoxide response but on genetic testing, in which patients carrying paternally inherited ABCC8 or KCNJ11 mutations should always be subjected to (18) F-DOPA PET-CT.
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Affiliation(s)
- Arianna Maiorana
- Department of Pediatrics, Metabolic Unit, IRCCS Bambino Gesù Children's Hospital, Rome, Italy
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Saint-Martin C, Zhou Q, Martin GM, Vaury C, Leroy G, Arnoux JB, de Lonlay P, Shyng SL, Bellanné-Chantelot C. Monoallelic ABCC8 mutations are a common cause of diazoxide-unresponsive diffuse form of congenital hyperinsulinism. Clin Genet 2014; 87:448-54. [PMID: 24814349 DOI: 10.1111/cge.12428] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Revised: 05/08/2014] [Accepted: 05/09/2014] [Indexed: 11/29/2022]
Abstract
ABCC8 encodes a subunit of the β-cell potassium channel (KATP ) whose loss of function is responsible for congenital hyperinsulinism (CHI). Patients with two recessive mutations of ABCC8 typically have severe diffuse forms of CHI unresponsive to diazoxide. Some dominant ABCC8 mutations are responsible for a subset of diffuse diazoxide-unresponsive forms of CHI. We report the analysis of 21 different ABCC8 mutations identified in 25 probands with diazoxide-unresponsive diffuse CHI and carrying a single mutation in ABCC8. Nine missense ABCC8 mutations were subjected to in vitro expression studies testing traffic efficiency and responses of mutant channels to activation by MgADP and diazoxide. Eight of the 9 missense mutations exhibited normal trafficking. Seven of the 8 mutants reaching the plasma membrane had dramatically reduced response to MgADP or to diazoxide (<10% of wild-type response). In our cohort, dominant KATP mutations account for 22% of the children with diffuse unresponsive-diazoxide CHI. Their clinical phenotype being indistinguishable from that of children with focal CHI and diffuse CHI forms due to two recessive KATP mutations, we show that functional testing is essential to make the most reliable diagnosis and offer appropriate genetic counseling.
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Affiliation(s)
- C Saint-Martin
- Department of Genetics, AP-HP Groupe Hospitalier Pitié-Salpétrière, Université Pierre et Marie Curie, Paris, France
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Yorifuji T. Congenital hyperinsulinism: current status and future perspectives. Ann Pediatr Endocrinol Metab 2014; 19:57-68. [PMID: 25077087 PMCID: PMC4114053 DOI: 10.6065/apem.2014.19.2.57] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/04/2014] [Accepted: 04/14/2014] [Indexed: 11/25/2022] Open
Abstract
The diagnosis and treatment of congenital hyperinsulinism (CHI) have made a remarkable progress over the past 20 years and, currently, it is relatively rare to see patients who are left with severe psychomotor delay. The improvement was made possible by the recent developments in the understanding of the molecular and pathological basis of CHI. Known etiologies include inactivating mutations of the KATP channel genes (ABCC8 and KCNJ11) and HNF4A, HNF1A, HADH, and UCP2 or activating mutations of GLUD1, GCK, and SLC16A1. The understanding of the focal form of KATP channel CHI and its detection by (18)F-fluoro-L-DOPA positron emission tomography have revolutionized the management of CHI, and many patients can be cured without postoperative diabetes mellitus. The incidence of the focal form appears to be higher in Asian countries; therefore, the establishment of treatment systems is even more important in this population. In addition to diazoxide or long-term subcutaneous infusion of octreotide or glucagon, long-acting octreotide or lanreotide have also been used successfully until spontaneous remission. Because of these medications, near-total pancreatectomy is less often performed even for the diazoxide-unresponsive diffuse form of CHI. Other promising medications include pasireotide, small-molecule correctors such as sulfonylurea or carbamazepine, GLP1 receptor antagonists, or mammalian target of rapamycin inhibitors. Unsolved questions in this field include the identification of the remaining genes responsible for CHI, the mechanisms leading to transient CHI, and the mechanisms responsible for the spontaneous remission of CHI. This article reviews recent developments and hypothesis regarding these questions.
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Affiliation(s)
- Tohru Yorifuji
- Department of Pediatric Endocrinology and Metabolism, Children's Medical Center, Osaka City General Hospital, Osaka, Japan
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Arya VB, Senniappan S, Demirbilek H, Alam S, Flanagan SE, Ellard S, Hussain K. Pancreatic endocrine and exocrine function in children following near-total pancreatectomy for diffuse congenital hyperinsulinism. PLoS One 2014; 9:e98054. [PMID: 24840042 PMCID: PMC4026387 DOI: 10.1371/journal.pone.0098054] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2014] [Accepted: 04/28/2014] [Indexed: 11/18/2022] Open
Abstract
Context Congenital hyperinsulinism (CHI), the commonest cause of persistent hypoglycaemia, has two main histological subtypes: diffuse and focal. Diffuse CHI, if medically unresponsive, is managed with near-total pancreatectomy. Post-pancreatectomy, in addition to persistent hypoglycaemia, there is a very high risk of diabetes mellitus and pancreatic exocrine insufficiency. Setting International referral centre for the management of CHI. Patients Medically unresponsive diffuse CHI patients managed with near-total pancreatectomy between 1994 and 2012. Intervention Near-total pancreatectomy. Main Outcome Measures Persistent hypoglycaemia post near-total pancreatectomy, insulin-dependent diabetes mellitus, clinical and biochemical (faecal elastase 1) pancreatic exocrine insufficiency. Results Of more than 300 patients with CHI managed during this time period, 45 children had medically unresponsive diffuse disease and were managed with near-total pancreatectomy. After near-total pancreatectomy, 60% of children had persistent hypoglycaemia requiring medical interventions. The incidence of insulin dependent diabetes mellitus was 96% at 11 years after surgery. Thirty-two patients (72%) had biochemical evidence of severe pancreatic exocrine insufficiency (Faecal elastase 1<100 µg/g). Clinical exocrine insufficiency was observed in 22 (49%) patients. No statistically significant difference in weight and height standard deviation score (SDS) was found between untreated subclinical pancreatic exocrine insufficiency patients and treated clinical pancreatic exocrine insufficiency patients. Conclusions The outcome of diffuse CHI patients after near-total pancreatectomy is very unsatisfactory. The incidence of persistent hypoglycaemia and insulin-dependent diabetes mellitus is very high. The presence of clinical rather than biochemical pancreatic exocrine insufficiency should inform decisions about pancreatic enzyme supplementation.
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Affiliation(s)
- Ved Bhushan Arya
- Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
- Institute of Child Health, University College London, London, United Kingdom
| | - Senthil Senniappan
- Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
- Institute of Child Health, University College London, London, United Kingdom
| | - Huseyin Demirbilek
- Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
- Institute of Child Health, University College London, London, United Kingdom
- Departments of Paediatric Endocrinology, Ankara Pediatric Hematology and Oncology Training Hospital, Ankara, Turkey
| | - Syeda Alam
- Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Sarah E. Flanagan
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, United Kingdom
| | - Sian Ellard
- Institute of Biomedical and Clinical Science, University of Exeter Medical School, Exeter, United Kingdom
| | - Khalid Hussain
- Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
- Institute of Child Health, University College London, London, United Kingdom
- * E-mail:
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Abstract
Persistent hyperinsulinaemic hypoglycaemia in infancy (PHHI) is a heterogeneous condition characterised by unregulated insulin secretion in response to a low blood glucose level. It is the most common cause of severe and persistent hypoglycaemia in neonates. It is extremely important to recognise this condition early and institute appropriate management to prevent significant brain injury leading to complications like epilepsy, cerebral palsy and neurological impairment. Histologically, PHHI is divided mainly into three types-diffuse, focal and atypical disease. Fluorine-18-l-3,4-dihydroxyphenylalanine positron emission tomography (18F-DOPA-PET/CT) scan allows differentiation between diffuse and focal diseases. The diffuse form is inherited in an autosomal recessive (or dominant) manner whereas the focal form is sporadic in inheritance and is localised to a small region of the pancreas. The molecular basis of PHHI involves defects in key genes (ABCC8, KCNJ11, GCK, SLC16A1, HADH, UCP2, HNF4A and GLUD1) that regulate insulin secretion. Focal lesions are cured by lesionectomy whereas diffuse disease (unresponsive to medical therapy) will require a near-total pancreatectomy with a risk of developing diabetes mellitus and pancreatic exocrine insufficiency. Open surgery is the traditional approach to pancreatic resection. However, recent advances in laparoscopic surgery have led to laparoscopic near-total pancreatectomy for diffuse lesions and laparoscopic distal pancreatectomy for focal lesions distal to the head of the pancreas.
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Affiliation(s)
- Pratik Shah
- Department of Developmental Endocrinology Research Group, Clinical and Molecular Genetics Unit, Institute of Child Health, University College London; Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London
| | - Huseyin Demirbilek
- Department of Developmental Endocrinology Research Group, Clinical and Molecular Genetics Unit, Institute of Child Health, University College London; Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London
| | - Khalid Hussain
- Department of Developmental Endocrinology Research Group, Clinical and Molecular Genetics Unit, Institute of Child Health, University College London; Department of Paediatric Endocrinology, Great Ormond Street Hospital for Children, London.
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Martin GM, Chen PC, Devaraneni P, Shyng SL. Pharmacological rescue of trafficking-impaired ATP-sensitive potassium channels. Front Physiol 2013; 4:386. [PMID: 24399968 PMCID: PMC3870925 DOI: 10.3389/fphys.2013.00386] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 12/09/2013] [Indexed: 12/25/2022] Open
Abstract
ATP-sensitive potassium (KATP) channels link cell metabolism to membrane excitability and are involved in a wide range of physiological processes including hormone secretion, control of vascular tone, and protection of cardiac and neuronal cells against ischemic injuries. In pancreatic β-cells, KATP channels play a key role in glucose-stimulated insulin secretion, and gain or loss of channel function results in neonatal diabetes or congenital hyperinsulinism, respectively. The β-cell KATP channel is formed by co-assembly of four Kir6.2 inwardly rectifying potassium channel subunits encoded by KCNJ11 and four sulfonylurea receptor 1 subunits encoded by ABCC8. Many mutations in ABCC8 or KCNJ11 cause loss of channel function, thus, congenital hyperinsulinism by hampering channel biogenesis and hence trafficking to the cell surface. The trafficking defects caused by a subset of these mutations can be corrected by sulfonylureas, KATP channel antagonists that have long been used to treat type 2 diabetes. More recently, carbamazepine, an anticonvulsant that is thought to target primarily voltage-gated sodium channels has been shown to correct KATP channel trafficking defects. This article reviews studies to date aimed at understanding the mechanisms by which mutations impair channel biogenesis and trafficking and the mechanisms by which pharmacological ligands overcome channel trafficking defects. Insight into channel structure-function relationships and therapeutic implications from these studies are discussed.
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Affiliation(s)
- Gregory M Martin
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University Portland, OR, USA
| | - Pei-Chun Chen
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University Portland, OR, USA
| | - Prasanna Devaraneni
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University Portland, OR, USA
| | - Show-Ling Shyng
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University Portland, OR, USA
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Chen PC, Olson EM, Zhou Q, Kryukova Y, Sampson HM, Thomas DY, Shyng SL. Carbamazepine as a novel small molecule corrector of trafficking-impaired ATP-sensitive potassium channels identified in congenital hyperinsulinism. J Biol Chem 2013; 288:20942-20954. [PMID: 23744072 DOI: 10.1074/jbc.m113.470948] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
ATP-sensitive potassium (KATP) channels consisting of sulfonylurea receptor 1 (SUR1) and the potassium channel Kir6.2 play a key role in insulin secretion by coupling metabolic signals to β-cell membrane potential. Mutations in SUR1 and Kir6.2 that impair channel trafficking to the cell surface lead to loss of channel function and congenital hyperinsulinism. We report that carbamazepine, an anticonvulsant, corrects the trafficking defects of mutant KATP channels previously identified in congenital hyperinsulinism. Strikingly, of the 19 SUR1 mutations examined, only those located in the first transmembrane domain of SUR1 responded to the drug. We show that unlike that reported for several other protein misfolding diseases, carbamazepine did not correct KATP channel trafficking defects by activating autophagy; rather, it directly improved the biogenesis efficiency of mutant channels along the secretory pathway. In addition to its effect on channel trafficking, carbamazepine also inhibited KATP channel activity. Upon subsequent removal of carbamazepine, however, the function of rescued channels was recovered. Importantly, combination of the KATP channel opener diazoxide and carbamazepine led to enhanced mutant channel function without carbamazepine washout. The corrector effect of carbamazepine on mutant KATP channels was also demonstrated in rat and human β-cells with an accompanying increase in channel activity. Our findings identify carbamazepine as a novel small molecule corrector that may be used to restore KATP channel expression and function in a subset of congenital hyperinsulinism patients.
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Affiliation(s)
- Pei-Chun Chen
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and
| | - Erik M Olson
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and
| | - Qing Zhou
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and
| | - Yelena Kryukova
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and
| | - Heidi M Sampson
- Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - David Y Thomas
- Department of Biochemistry, McGill University, Montréal, Québec H3G 1Y6, Canada
| | - Show-Ling Shyng
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and.
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Yorifuji T, Kawakita R, Hosokawa Y, Fujimaru R, Matsubara K, Aizu K, Suzuki S, Nagasaka H, Nishibori H, Masue M. Efficacy and safety of long-term, continuous subcutaneous octreotide infusion for patients with different subtypes of KATP-channel hyperinsulinism. Clin Endocrinol (Oxf) 2013; 78:891-7. [PMID: 23067144 DOI: 10.1111/cen.12075] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 07/31/2012] [Accepted: 10/10/2012] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To evaluate the efficacy of long-term, continuous, subcutaneous octreotide infusion for congenital hyperinsulinism caused by mutations in the KATP-channel genes, KCNJ11 and ABCC8. PATIENTS Fifteen Japanese patients with diazoxide-unresponsive, KATP-channel hyperinsulinism. METHODS Molecular diagnoses were made by sequencing and multiple ligation-dependent probe amplification analysis. In patients with paternally inherited, monoallelic mutations, 18F-DOPA PET scans were performed to determine the location of the lesion. The patients were treated with continuous, subcutaneous octreotide infusion at a dosage of up to 25 μg/kg/day, using an insulin pump to maintain blood glucose levels higher than 3.33 mmol/l. Additional treatments (IV glucose, glucagon or enteral feeding) were administered as needed. The efficacy of the treatment was assessed in patients who received octreotide for 4 months to 5.9 years. RESULTS Three patients had biallelic mutations, and 12 had monoallelic, paternally inherited mutations. Four patients with monoallelic mutations showed diffuse 18F-DOPA uptake, whereas seven patients showed focal uptake. Octreotide was effective in all the patients. The patients with biallelic mutations required a higher dosage (17-25 μg/kg/day), and two patients required additional treatments. By contrast, the patients with monoallelic mutations required a lower dosage (0.5-21 μg/kg/day) irrespective of the PET results and mostly without additional treatments. Treatment was discontinued in three patients at 2.5, 3.3 and 5.9 years of age, without psychomotor delay. Except for growth deceleration at a higher dosage, no significant adverse effects were noted. CONCLUSIONS Long-term, continuous, subcutaneous octreotide infusion is a feasible alternative to surgery especially for patients with monoallelic KATP-channel mutations.
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Affiliation(s)
- Tohru Yorifuji
- Department of Pediatric Endocrinology and Metabolism, Children's Medical Center, Osaka City General Hospital, Osaka, Japan.
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Henquin JC, Sempoux C, Marchandise J, Godecharles S, Guiot Y, Nenquin M, Rahier J. Congenital hyperinsulinism caused by hexokinase I expression or glucokinase-activating mutation in a subset of β-cells. Diabetes 2013; 62:1689-96. [PMID: 23274908 PMCID: PMC3636634 DOI: 10.2337/db12-1414] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Congenital hyperinsulinism causes persistent hypoglycemia in neonates and infants. Most often, uncontrolled insulin secretion (IS) results from a lack of functional K(ATP) channels in all β-cells or only in β-cells within a resectable focal lesion. In more rare cases, without K(ATP) channel mutations, hyperfunctional islets are confined within few lobules, whereas hypofunctional islets are present throughout the pancreas. They also can be cured by selective partial pancreatectomy; however, unlike those with a K(ATP) focal lesion, they show clinical sensitivity to diazoxide. Here, we characterized in vitro IS by fragments of pathological and adjacent normal pancreas from six such cases. Responses of normal pancreas were unremarkable. In pathological region, IS was elevated at 1 mmol/L and was further increased by 15 mmol/L glucose. Diazoxide suppressed IS and tolbutamide antagonized the inhibition. The most conspicuous anomaly was a large stimulation of IS by 1 mmol/L glucose. In five of six cases, immunohistochemistry revealed undue presence of low-K(m) hexokinase-I in β-cells of hyperfunctional islets only. In one case, an activating mutation of glucokinase (I211F) was found in pathological islets only. Both abnormalities, attributed to somatic genetic events, may account for inappropriate IS at low glucose levels by a subset of β-cells. They represent a novel cause of focal congenital hyperinsulinism.
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Affiliation(s)
- Jean-Claude Henquin
- Unit of Endocrinology and Metabolism, University of Louvain, Faculty of Medicine, Brussels, Belgium.
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Kapoor RR, Flanagan SE, Arya VB, Shield JP, Ellard S, Hussain K. Clinical and molecular characterisation of 300 patients with congenital hyperinsulinism. Eur J Endocrinol 2013; 168:557-64. [PMID: 23345197 PMCID: PMC3599069 DOI: 10.1530/eje-12-0673] [Citation(s) in RCA: 158] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Congenital hyperinsulinism (CHI) is a clinically heterogeneous condition. Mutations in eight genes (ABCC8, KCNJ11, GLUD1, GCK, HADH, SLC16A1, HNF4A and HNF1A) are known to cause CHI. AIM To characterise the clinical and molecular aspects of a large cohort of patients with CHI. METHODOLOGY Three hundred patients were recruited and clinical information was collected before genotyping. ABCC8 and KCNJ11 genes were analysed in all patients. Mutations in GLUD1, HADH, GCK and HNF4A genes were sought in patients with diazoxide-responsive CHI with hyperammonaemia (GLUD1), raised 3-hydroxybutyrylcarnitine and/or consanguinity (HADH), positive family history (GCK) or when CHI was diagnosed within the first week of life (HNF4A). RESULTS Mutations were identified in 136/300 patients (45.3%). Mutations in ABCC8/KCNJ11 were the commonest genetic cause identified (n=109, 36.3%). Among diazoxide-unresponsive patients (n=105), mutations in ABCC8/KCNJ11 were identified in 92 (87.6%) patients, of whom 63 patients had recessively inherited mutations while four patients had dominantly inherited mutations. A paternal mutation in the ABCC8/KCNJ11 genes was identified in 23 diazoxide-unresponsive patients, of whom six had diffuse disease. Among the diazoxide-responsive patients (n=183), mutations were identified in 41 patients (22.4%). These include mutations in ABCC8/KCNJ11 (n=15), HNF4A (n=7), GLUD1 (n=16) and HADH (n=3). CONCLUSIONS A genetic diagnosis was made for 45.3% of patients in this large series. Mutations in the ABCC8 gene were the commonest identifiable cause. The vast majority of patients with diazoxide-responsive CHI (77.6%) had no identifiable mutations, suggesting other genetic and/or environmental mechanisms.
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Affiliation(s)
| | - Sarah E Flanagan
- Institute of Biomedical and Clinical Science, University of Exeter Medical SchoolExeter, EX2 5DWUK
| | | | - Julian P Shield
- Department of Child Health, Bristol Royal Hospital for ChildrenBristol, BS2 8BJUK
| | - Sian Ellard
- Institute of Biomedical and Clinical Science, University of Exeter Medical SchoolExeter, EX2 5DWUK
| | - Khalid Hussain
- (Correspondence should be addressed to K Hussain who is now at Molecular Genetics Unit, Developmental Endocrinology Research Group, Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK; )
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