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1.
J Clin Endocrinol Metab ; 108(9): e823-e831, 2023 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-36810692

RESUMO

CONTEXT: Endocrine complications are common in pediatric brain tumor patients. OBJECTIVE: To describe hypothalamic-pituitary-gonadal axis (HPGA) function in patients treated in childhood for a primary brain tumor more than 5 years earlier, in order to identify risk factors for HPGA impairment. METHODS: We retrospectively included 204 patients diagnosed with a primary brain tumor before 18 years of age and monitored at the pediatric endocrinology unit of the Necker Enfants-Malades University Hospital (Paris, France) between January 2010 and December 2015. Patients with pituitary adenoma or untreated glioma were excluded. RESULTS: Among patients with suprasellar glioma not treated by radiotherapy, the prevalence of advanced puberty was 65% overall and 70% when the diagnosis occurred before 5 years of age. Medulloblastoma chemotherapy caused gonadal toxicity in 70% of all patients and in 87.5% of those younger than 5 years at diagnosis. In the group with craniopharyngioma, 70% of patients had hypogonadotropic hypogonadism, which was consistently accompanied by growth hormone deficiency. CONCLUSION: Tumor type, location, and treatment were the risk main factors for HPGA impairment. Awareness that onset can be delayed is essential to guide information of parents and patients, patient monitoring, and timely hormone replacement therapy.


Assuntos
Neoplasias Encefálicas , Glioma , Criança , Humanos , Eixo Hipotalâmico-Hipofisário-Gonadal , Estudos Retrospectivos , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/terapia , Puberdade
2.
J Clin Endocrinol Metab ; 107(5): e2156-e2166, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-34918112

RESUMO

CONTEXT: Endocrine complications are common in pediatric brain tumor patients. OBJECTIVE: We aimed to describe the endocrine follow-up of patients with primary brain tumors. METHODS: This is a noninterventional observational study based on data collection from medical records of 221 patients followed at a Pediatric Endocrinology Department. RESULTS: Median age at diagnosis was 6.7 years (range, 0-15.9), median follow-up 6.7 years (0.3-26.6), 48.9% female. Main tumor types were medulloblastoma (37.6%), craniopharyngioma (29.0%), and glioma (20.4%). By anatomic location, 48% were suprasellar (SS) and 52% non-suprasellar (NSS). Growth hormone deficiency (GHD) prevalence was similar in both groups (SS: 83.0%, NSS: 76.5%; P = 0.338), appearing at median 1.8 years (-0.8 to 12.4) after diagnosis; postradiotherapy GHD appeared median 1.6 years after radiotherapy (0.2-10.7). Hypothyroidism was more prevalent in SS (76.4%), than NSS (33.9%) (P < 0.001), as well as ACTH deficiency (SS: 69.8%, NSS: 6.1%; P < 0.001). Early puberty was similar in SS (16%) and NSS (12.2%). Hypogonadotropic hypogonadism was predominant in SS (63.1%) vs NSS (1.3%), P < 0.001, and postchemotherapy gonadal toxicity in NSS (29.6%) vs SS (2.8%), P < 0.001. Adult height was lower for NSS compared to target height (-1.0 SD, P < 0.0001) and to SS patients (P < 0.0001). Thyroid nodules were found in 13/45 patients (28.8%), including 4 cancers (4.8-11.5 years after radiotherapy). Last follow-up visit BMI was higher in both groups (P = 0.0001), and obesity incidence was higher for SS (46.2%) than NSS (17.4%). CONCLUSION: We found a high incidence of early-onset endocrine disorders. An endocrine consultation and nutritional evaluation should be mandatory for all patients with a brain tumor, especially when the tumor is suprasellar or after hypothalamus/pituitary irradiation.


Assuntos
Neoplasias Encefálicas , Neoplasias Cerebelares , Doenças do Sistema Endócrino , Neoplasias Hipofisárias , Adulto , Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/radioterapia , Neoplasias Cerebelares/complicações , Neoplasias Cerebelares/radioterapia , Criança , Doenças do Sistema Endócrino/diagnóstico , Doenças do Sistema Endócrino/epidemiologia , Doenças do Sistema Endócrino/etiologia , Feminino , Humanos , Masculino , Neoplasias Hipofisárias/complicações , Neoplasias Hipofisárias/epidemiologia , Prevalência , Estudos Retrospectivos
3.
Diabetes Care ; 43(6): 1191-1199, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32273272

RESUMO

OBJECTIVE: Transient neonatal diabetes mellitus (TNDM) occurs during the 1st year of life and remits during childhood. We investigated glucose metabolism and socioeducational outcomes in adults. RESEARCH DESIGN AND METHODS: We included 27 participants with a history of TNDM currently with (n = 24) or without (n = 3) relapse of diabetes and 16 non-TNDM relatives known to be carriers of causal genetic defects and currently with (n = 9) or without (n = 7) diabetes. Insulin sensitivity and secretion were assessed by hyperinsulinemic-euglycemic clamp and arginine-stimulation testing in a subset of 8 TNDM participants and 7 relatives carrying genetic abnormalities, with and without diabetes, compared with 17 unrelated control subjects without diabetes. RESULTS: In TNDM participants, age at relapse correlated positively with age at puberty (P = 0.019). The mean insulin secretion rate and acute insulin response to arginine were significantly lower in TNDM participants and relatives of participants with diabetes than in control subjects (median 4.7 [interquartile range 3.7-5.7] vs. 13.4 [11.8-16.1] pmol/kg/min, P < 0.0001; and 84.4 [33.0-178.8] vs. 399.6 [222.9-514.9] µIU/mL, P = 0.0011), but were not different between participants without diabetes (12.7 [10.4-14.3] pmol/kg/min and 396.3 [303.3-559.3] µIU/mL, respectively) and control subjects. Socioeducational attainment was lower in TNDM participants than in the general population, regardless of diabetes duration. CONCLUSIONS: Relapse of diabetes occurred earlier in TNDM participants compared with relatives and was associated with puberty. Both groups had decreased educational attainment, and those with diabetes had lower insulin secretion capacity; however, there was no difference in insulin resistance in adulthood. These forms of diabetes should be included in maturity-onset diabetes of the young testing panels, and relatives of TNDM patients should be screened for underlying defects, as they may be treated with drugs other than insulin.


Assuntos
Diabetes Mellitus/congênito , Diabetes Mellitus/diagnóstico , Escolaridade , Doenças do Recém-Nascido/diagnóstico , Resistência à Insulina , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Estudos Transversais , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/metabolismo , Feminino , Técnica Clamp de Glucose , Humanos , Recém-Nascido , Doenças do Recém-Nascido/epidemiologia , Doenças do Recém-Nascido/metabolismo , Resistência à Insulina/fisiologia , Secreção de Insulina/fisiologia , Estudos Longitudinais , Masculino , Prognóstico , Fatores Socioeconômicos , Adulto Jovem
5.
Diabetes Care ; 38(11): 2033-41, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26438614

RESUMO

OBJECTIVE: Neonatal diabetes secondary to mutations in potassium-channel subunits is a rare disease but constitutes a paradigm for personalized genetics-based medicine, as replacing the historical treatment with insulin injections with oral sulfonylurea (SU) therapy has been proven beneficial. SU receptors are widely expressed in the brain, and we therefore evaluated potential effects of SU on neurodevelopmental parameters, which are known to be unresponsive to insulin. RESEARCH DESIGN AND METHODS: We conducted a prospective single-center study. Nineteen patients (15 boys aged 0.1-18.5 years) were switched from insulin to SU therapy. MRI was performed at baseline. Before and 6 or 12 months after the switch, patients underwent quantitative neurological and developmental assessments and electrophysiological nerve and muscle testing. RESULTS: At baseline, hypotonia, deficiencies in gesture conception or realization, and attention disorders were common. SU improved HbA1c levels (median change -1.55% [range -3.8 to 0.1]; P < 0.0001), intelligence scores, hypotonia (in 12 of 15 patients), visual attention deficits (in 10 of 13 patients), gross and fine motor skills (in all patients younger than 4 years old), and gesture conception and realization (in 5 of 8 older patients). Electrophysiological muscle and nerve tests were normal. Cerebral MRI at baseline showed lesions in 12 patients, suggesting that the impairments were central in origin. CONCLUSIONS: SU therapy in neonatal diabetes secondary to mutations in potassium-channel subunits produces measurable improvements in neuropsychomotor impairments, which are greater in younger patients. An early genetic diagnosis should always be made, allowing for a rapid switch to SU.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/genética , Substituição de Medicamentos , Glibureto/uso terapêutico , Hipoglicemiantes/uso terapêutico , Canais de Potássio Corretores do Fluxo de Internalização/genética , Administração Oral , Adolescente , Encéfalo/patologia , Criança , Pré-Escolar , Diabetes Mellitus/fisiopatologia , Feminino , Glibureto/administração & dosagem , Humanos , Hipoglicemiantes/administração & dosagem , Lactente , Recém-Nascido , Insulina/administração & dosagem , Insulina/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Mutação , Manifestações Neurológicas , Testes Neuropsicológicos , Desempenho Psicomotor , Receptores de Sulfonilureias/genética
6.
Horm Res Paediatr ; 83(4): 262-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25677445

RESUMO

AIMS: To describe cortisol response to tetracosactide and to review the literature on adrenal function in non-classic congenital adrenal hyperplasia (NCCAH) patients. METHODS: We compared cortisol responses to tetracosactide (250 µg) between NCCAH patients and a comparison group (CG) of patients with premature pubarche and normal tetracosactide test. An adequate cortisol response was defined as a peak ≥18 µg/dl. RESULTS: We included 35 NCCAH patients (26 girls, 9 boys), whose mean age at testing was 7.0 years (0.8-15.6), and 47 patients in the CG (39 girls, 8 boys), whose mean age was 7.2 years (0.5-9.9). Baseline cortisol was significantly higher in the NCCAH group than in the CG [12.9 (4.3-22.2) vs. 9.7 (4.2-16.2) µg/dl, respectively; p = 0.0006]. NCCAH patients had lower cortisol peak response compared to the CG [18.2 (6.3-40) vs. 24.9 (12-30.3) µg/dl, respectively; p < 0.0001]. Peak cortisol was <18 µg/dl in 21/35 (60%) NCCAH patients versus 1/47 (2.1%) in the CG. No NCCAH patients had acute adrenal insufficiency, but 2 reported severe fatigue that improved with hydrocortisone. CONCLUSIONS: The cortisol response to tetracosactide was inadequate (<18 µg/dl) in 60% of patients with NCCAH. Hydrocortisone therapy may deserve consideration when major stress (surgery, trauma, childbirth) or objectively documented fatigue occurs in NCCAH patients with inadequate cortisol response.


Assuntos
Hiperplasia Suprarrenal Congênita/diagnóstico , Testes de Função Adreno-Hipofisária , Adolescente , Hiperplasia Suprarrenal Congênita/sangue , Criança , Pré-Escolar , Cosintropina , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
Horm Res Paediatr ; 82(6): 364-71, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25377653

RESUMO

BACKGROUND: Patients with brain tumours have a high risk of water and electrolyte disorders (WED). Postsurgery diabetes insipidus (DI) may be transient or permanent, the syndrome of inappropriate antidiuretic hormone secretion (SIADH) and cerebral salt-wasting syndrome (CSWS) are usually transient. METHODS: Retrospective study, including patients with suprasellar tumours, treated at Hôpital Necker, Institut Gustave-Roussy or Institut Curie, in Île-de-France, between 2007 and 2011. WED were noted if they persisted >1 month after surgery. RESULTS: 159 patients were included, 54.1% girls, 43.9% boys. Tumour types were: glioma (43.4%), craniopharyngioma (43.4%), germinoma (11.3%), others (1.9%). Age at diagnosis was 7.1 ± 4.6 years. The median time from end of treatment was 1.9 (0-7.8) years. DI was the most frequent disorder after tumour treatment (50.3%) and was significantly associated with surgery (p < 0.001). Persistent CSWS was present in 3.6%, persistent SIADH in 1.3%. Two cases of hypernatraemia were due to adipsia. Thyrotropin deficiency after treatment was noted in 68.9% of patients tested, adrenocorticotropin deficiency in 66.2%. CONCLUSIONS: Patients with suprasellar tumours have a high incidence of long-term WED, mainly DI. Assessment of thyrotroph and corticotroph function, and thirst sensation, is necessary to diagnose and manage these disorders correctly. CSWS may be persistent in few patients and requires special attention to prescribe the appropriate care.


Assuntos
Neoplasias Encefálicas/epidemiologia , Craniofaringioma/epidemiologia , Glioma/epidemiologia , Síndrome de Secreção Inadequada de HAD/epidemiologia , Neoplasias Hipofisárias/epidemiologia , Síndrome de Emaciação/epidemiologia , Desequilíbrio Hidroeletrolítico/epidemiologia , Adolescente , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/terapia , Criança , Pré-Escolar , Craniofaringioma/complicações , Craniofaringioma/terapia , Feminino , Seguimentos , Glioma/complicações , Glioma/terapia , Humanos , Síndrome de Secreção Inadequada de HAD/etiologia , Incidência , Lactente , Masculino , Neoplasias Hipofisárias/complicações , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Síndrome de Emaciação/etiologia , Desequilíbrio Hidroeletrolítico/etiologia
8.
Lancet Diabetes Endocrinol ; 1(3): 199-207, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24622368

RESUMO

BACKGROUND: Neonatal diabetes mellitus is a rare genetic form of pancreatic ß-cell dysfunction. We compared phenotypic features and clinical outcomes according to genetic subtypes in a cohort of patients diagnosed with neonatal diabetes mellitus before age 1 year, without ß-cell autoimmunity and with normal pancreas morphology. METHODS: We prospectively investigated patients from 20 countries referred to the French Neonatal Diabetes Mellitus Study Group from 1995 to 2010. Patients with hyperglycaemia requiring treatment with insulin before age 1 year were eligible, provided that they had normal pancreatic morphology as assessed by ultrasonography and negative tests for ß-cell autoimmunity. We assessed changes in the 6q24 locus, KATP-channel subunit genes (ABCC8 and KCNJ11), and preproinsulin gene (INS) and investigated associations between genotype and phenotype, with special attention to extra-pancreatic abnormalities. FINDINGS: We tested 174 index patients, of whom 47 (27%) had no detectable genetic defect. Of the remaining 127 index patients, 40 (31%) had 6q24 abnormalities, 43 (34%) had mutations in KCNJ11, 31 (24%) had mutations in ABCC8, and 13 (10%) had mutations in INS. We reported developmental delay with or without epilepsy in 13 index patients (18% of participants with mutations in genes encoding KATP channel subunits). In-depth neuropsychomotor investigations were done at median age 7 years (IQR 1-15) in 27 index patients with mutations in KATP channel subunit genes who did not have developmental delay or epilepsy. Developmental coordination disorder (particularly visual-spatial dyspraxia) or attention deficits were recorded in all index patients who had this testing. Compared with index patients who had mutations in KATP channel subunit genes, those with 6q24 abnormalities had specific features: developmental defects involving the heart, kidneys, or urinary tract (8/36 [22%] vs 2/71 [3%]; p=0·002), intrauterine growth restriction (34/37 [92%] vs 34/70 [48%]; p<0·0001), and early diagnosis (median age 5·0 days, IQR 1·0-14·5 vs 45·5 days, IQR 27·2-95·0; p<0·0001). Remission of neonatal diabetes mellitus occurred in 89 (51%) index patients at a median age of 17 weeks (IQR 9·5-39·0; median follow-up 4·7 years, IQR 1·5-12·8). Recurrence was common, with no difference between the groups who had 6q24 abnormalities versus mutations in KATP channel subunit genes (82% vs 86%; p=0·36). INTERPRETATION: Neonatal diabetes mellitus is often associated with neuropsychological dysfunction and developmental defects that are specific to the underlying genetic abnormality. A multidisciplinary assessment is therefore essential when patients are diagnosed. Features of neuropsychological dysfunction and developmental defects should be tested for in adults with a history of neonatal diabetes mellitus. FUNDING: Agence Nationale de la Recherche-Maladies Rares Research Program Grant, the Transnational European Research Grant on Rare Diseases, the Société Francophone du Diabète-Association Française du Diabète, the Association Française du Diabète, Aide aux Jeunes Diabétiques, a CIFRE grant from the French Government, HRA-Pharma, the French Ministry of Education and Research, and the Société Française de Pédiatrie.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 6/genética , Deficiências do Desenvolvimento/genética , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/genética , Fenótipo , Transtornos Psicomotores/genética , Criança , Estudos de Coortes , Deficiências do Desenvolvimento/patologia , França/epidemiologia , Estudos de Associação Genética , Humanos , Lactente , Recém-Nascido , Insulina/genética , Estimativa de Kaplan-Meier , Mutação/genética , Pâncreas/diagnóstico por imagem , Canais de Potássio Corretores do Fluxo de Internalização/genética , Estudos Prospectivos , Precursores de Proteínas/genética , Transtornos Psicomotores/patologia , Receptores de Sulfonilureias/genética , Ultrassonografia
9.
Horm Res Paediatr ; 78(3): 193-200, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22986916

RESUMO

BACKGROUND: Laron syndrome is caused by a mutation in the growth hormone (GH) receptor and manifests as insulin-like growth factor-I (IGF-I) deficiency, severe short stature, and early hypoglycemia. We report a case with postprandial hyperglycemia, an abnormality not reported previously. Postprandial hyperglycemia was due to chronic IGF-I deficiency, and was reversed by IGF-I replacement therapy. METHODS: A Moroccan girl referred for short stature at 7 years and 8 months of age had dwarfism [height, 78 cm (-9 SDs); weight, 10 kg (-4 SDs)], hypoglycemia, and truncal obesity. Her serum IGF-I level was very low, and her baseline serum GH level was elevated to 47 mIU/l. Molecular analysis showed a homozygous mutation in the GH receptor gene. RESULTS: Continuous glucose monitoring before treatment showed asymptomatic hypoglycemia with postprandial hyperglycemia (2.5 g/l, 13.75 mmol/l). Treatment with recombinant human IGF-I (mecasermin, Increlex®) was started. The blood glucose profile improved with 0.04 µg/kg/day and returned to normal with 0.12 µg/kg/day. CONCLUSION: Postprandial hyperglycemia is a metabolic consequence of chronic IGF-I deficiency. The beneficial effect of IGF-I replacement therapy may be ascribable to improved postprandial transfer of glucose.


Assuntos
Terapia de Reposição Hormonal , Hiperglicemia/tratamento farmacológico , Fator de Crescimento Insulin-Like I/uso terapêutico , Síndrome de Laron/tratamento farmacológico , Criança , Feminino , Humanos , Hiperglicemia/sangue , Hiperglicemia/complicações , Síndrome de Laron/sangue , Síndrome de Laron/complicações , Proteínas Recombinantes/uso terapêutico
10.
JAMA ; 306(1): 70-8, 2011 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-21730243

RESUMO

CONTEXT: Lopinavir-ritonavir is a human immunodeficiency virus 1 (HIV-1) protease inhibitor boosted by ritonavir, a cytochrome p450 inhibitor. A warning about its tolerance in premature newborns was recently released, and transient elevation of 17-hydroxyprogesterone (17OHP) was noted in 2 newborns treated with lopinavir-ritonavir in France. OBJECTIVE: To evaluate adrenal function in newborns postnatally treated with lopinavir-ritonavir. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cross-sectional analysis of the database from the national screening for congenital adrenal hyperplasia (CAH) and the French Perinatal Cohort. Comparison of HIV-1-uninfected newborns postnatally treated with lopinavir-ritonavir and controls treated with standard zidovudine. MAIN OUTCOME MEASURES: Plasma 17OHP and dehydroepiandrosterone-sulfate (DHEA-S) concentrations during the first week of treatment. Clinical and biological symptoms compatible with adrenal deficiency. RESULTS: Of 50 HIV-1-uninfected newborns who received lopinavir-ritonavir at birth for a median of 30 days (interquartile range [IQR], 25-33), 7 (14%) had elevated 17OHP levels greater than 16.5 ng/mL for term infants (>23.1 ng/mL for preterm) on days 1 to 6 vs 0 of 108 controls having elevated levels. The median 17OHP concentration for 42 term newborns treated with lopinavir-ritonavir was 9.9 ng/mL (IQR, 3.9-14.1 ng/mL) vs 3.7 ng/mL (IQR, 2.6-5.3 ng/mL) for 93 term controls (P < .001). The difference observed in median 17OHP values between treated newborns and controls was higher in children also exposed in utero (11.5 ng/mL vs 3.7 ng/mL; P < .001) than not exposed in utero (6.9 ng/mL vs 3.3 ng/mL; P = .03). The median DHEA-S concentration among 18 term newborns treated with lopinavir-ritonavir was 9242 ng/mL (IQR, 1347-25,986 ng/mL) compared with 484 ng/mL (IQR, 218-1308 ng/mL) among 17 term controls (P < .001). The 17OHP and DHEA-S concentrations were positively correlated (r = 0.53; P = .001). All term newborns treated with lopinavir-ritonavir were asymptomatic, although 3 premature newborns experienced life-threatening symptoms compatible with adrenal insufficiency, including hyponatremia and hyperkalemia with, in 1 case, cardiogenic shock. All symptoms resolved following completion of the lopinavir-ritonavir treatment. CONCLUSION: Among newborn children of HIV-1-infected mothers exposed in utero to lopinavir-ritonavir, postnatal treatment with a lopinavir-ritonavir-based regimen, compared with a zidovudine-based regimen, was associated with transient adrenal dysfunction.


Assuntos
Insuficiência Adrenal/induzido quimicamente , Infecções por HIV/transmissão , HIV-1 , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Pirimidinonas/efeitos adversos , Ritonavir/efeitos adversos , 17-alfa-Hidroxiprogesterona/sangue , Insuficiência Adrenal/sangue , Insuficiência Adrenal/epidemiologia , Estudos de Casos e Controles , Estudos Transversais , Sulfato de Desidroepiandrosterona/sangue , Feminino , França/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Recém-Nascido , Lopinavir , Masculino , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Pirimidinonas/administração & dosagem , Estudos Retrospectivos , Ritonavir/administração & dosagem , Zidovudina/administração & dosagem
11.
J Biol Chem ; 286(32): 28414-24, 2011 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-21592955

RESUMO

Krüppel-like transcription factors (KLFs) have elicited significant attention because of their regulation of essential biochemical pathways and, more recently, because of their fundamental role in the mechanisms of human diseases. Neonatal diabetes mellitus is a monogenic disorder with primary alterations in insulin secretion. We here describe a key biochemical mechanism that underlies neonatal diabetes mellitus insulin biosynthesis impairment, namely a homozygous mutation within the insulin gene (INS) promoter, c.-331C>G, which affects a novel KLF-binding site. The combination of careful expression profiling, electromobility shift assays, reporter experiments, and chromatin immunoprecipitation demonstrates that, among 16 different KLF proteins tested, KLF11 is the most reliable activator of this site. Congruently, the c.-331C>G INS mutation fails to bind KLF11, thus inhibiting activation by this transcription factor. Klf11(-/-) mice recapitulate the disruption in insulin production and blood levels observed in patients. Thus, these data demonstrate an important role for KLF11 in the regulation of INS transcription via the novel c.-331 KLF site. Lastly, our screening data raised the possibility that other members of the KLF family may also regulate this promoter under distinct, yet unidentified, cellular contexts. Collectively, this study underscores a key role for KLF proteins in biochemical mechanisms of human diseases, in particular, early infancy onset diabetes mellitus.


Assuntos
Proteínas de Ciclo Celular , Proteínas de Ligação a DNA , Diabetes Mellitus , Doenças do Recém-Nascido , Células Secretoras de Insulina , Insulina , Mutagênese Insercional , Proteínas Repressoras , Elementos de Resposta/genética , Transativadores , Fatores de Transcrição , Adulto , Animais , Proteínas Reguladoras de Apoptose , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular , Pré-Escolar , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Feminino , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido/genética , Doenças do Recém-Nascido/metabolismo , Doenças do Recém-Nascido/patologia , Insulina/biossíntese , Insulina/genética , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Masculino , Camundongos , Camundongos Knockout , Ratos , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transativadores/genética , Transativadores/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Eur J Endocrinol ; 164(2): 309-14, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21098685

RESUMO

CONTEXT: Monocarboxylate transporter 8 (MCT8 or SLC16A2) mutations cause X-linked Allan-Herndon-Dudley syndrome. Heterozygous females are usually asymptomatic, but pregnancy may modify thyroid function and MCT8 is expressed in the placenta, suggesting that maternal and fetal abnormalities might develop even in the absence of MCT8 fetal mutation. Genetic counseling is so far based on X-linked transmission, and prenatal diagnosis is rarely performed. OBJECTIVE: To describe thyroid function and the prenatal diagnosis in pregnant mothers harboring heterozygous MCT8 mutations and management of the persistent maternal hypothyroxinemia. Patients Two women heterozygous for MCT8 mutations (c.1690G>A and c.1393-1G>C) were monitored throughout pregnancy. METHODS: Prenatal diagnosis included sex determination, direct MCT8 sequencing, and familial linkage analysis. Ultrasonography and hormonal assays for maternal thyroid function evaluation were performed serially during pregnancy. Neonatal thyroid hormonal status was assessed. RESULTS: None of the three fetuses (two males and one female) carried MCT8 mutations. One of the two heterozygous mothers revealed gestational hypothyroxinemia, prompting early levothyroxine (l-T4) therapy until delivery. The second heterozygous mother showed normal thyroid function but was preventively traited by l-T4 and all of the three neonates had normal thyroid hormone levels and thyroid gland at birth, suggesting advantages of prenatal care and/or compensatory mechanisms. CONCLUSION: Heterozygous MCT8 women should be monitored for requirement of l-T4 therapy to prevent fetal and neonatal hypothyroidism and to avoid risk of potential cognitive delay due to gestational hypothyroxinemia. Moreover, when the disease-causing mutation is known and/or the first child is affected, prenatal diagnosis for male fetuses should be assessed early for MCT8 mutations by direct sequencing.


Assuntos
Predisposição Genética para Doença , Hipotireoidismo/genética , Transportadores de Ácidos Monocarboxílicos/genética , Adulto , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Diagnóstico Pré-Natal , Risco , Simportadores , Testes de Função Tireóidea
13.
PLoS One ; 5(10): e13630, 2010 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-21049026

RESUMO

BACKGROUND: Accurate molecular diagnosis of monogenic non-autoimmune neonatal diabetes mellitus (NDM) is critical for patient care, as patients carrying a mutation in KCNJ11 or ABCC8 can be treated by oral sulfonylurea drugs instead of insulin therapy. This diagnosis is currently based on Sanger sequencing of at least 42 PCR fragments from the KCNJ11, ABCC8, and INS genes. Here, we assessed the feasibility of using the next-generation whole exome sequencing (WES) for the NDM molecular diagnosis. METHODOLOGY/PRINCIPAL FINDINGS: We carried out WES for a patient presenting with permanent NDM, for whom mutations in KCNJ11, ABCC8 and INS and abnormalities in chromosome 6q24 had been previously excluded. A solution hybridization selection was performed to generate WES in 76 bp paired-end reads, by using two channels of the sequencing instrument. WES quality was assessed using a high-resolution oligonucleotide whole-genome genotyping array. From our WES with high-quality reads, we identified a novel non-synonymous mutation in ABCC8 (c.1455G>C/p.Q485H), despite a previous negative sequencing of this gene. This mutation, confirmed by Sanger sequencing, was not present in 348 controls and in the patient's mother, father and young brother, all of whom are normoglycemic. CONCLUSIONS/SIGNIFICANCE: WES identified a novel de novo ABCC8 mutation in a NDM patient. Compared to the current Sanger protocol, WES is a comprehensive, cost-efficient and rapid method to identify mutations in NDM patients. We suggest WES as a near future tool of choice for further molecular diagnosis of NDM cases, negative for chr6q24, KCNJ11 and INS abnormalities.


Assuntos
Diabetes Mellitus/diagnóstico , Éxons , Doenças do Recém-Nascido/diagnóstico , Técnicas de Diagnóstico Molecular , Cromossomos Humanos Par 6 , Diabetes Mellitus/genética , Humanos , Recém-Nascido , Doenças do Recém-Nascido/genética , Mutação , Polimorfismo de Nucleotídeo Único
14.
Diabetes ; 59(3): 653-61, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20007936

RESUMO

OBJECTIVE: Heterozygous mutations in the human preproinsulin (INS) gene are a cause of nonsyndromic neonatal or early-infancy diabetes. Here, we sought to identify INS mutations associated with maturity-onset diabetes of the young (MODY) or nonautoimmune diabetes in mid-adult life, and to explore the molecular mechanisms involved. RESEARCH DESIGN AND METHODS: The INS gene was sequenced in 16 French probands with unexplained MODY, 95 patients with nonautoimmune early-onset diabetes (diagnosed at <35 years) and 292 normoglycemic control subjects of French origin. Three identified insulin mutants were generated by site-directed mutagenesis of cDNA encoding a preproinsulin-green fluorescent protein (GFP) (C-peptide) chimera. Intracellular targeting was assessed in clonal beta-cells by immunocytochemistry and proinsulin secretion, by radioimmunoassay. Spliced XBP1 and C/EBP homologous protein were quantitated by real-time PCR. RESULTS: A novel coding mutation, L30M, potentially affecting insulin multimerization, was identified in five diabetic individuals (diabetes onset 17-36 years) in a single family. L30M preproinsulin-GFP fluorescence largely associated with the endoplasmic reticulum (ER) in MIN6 beta-cells, and ER exit was inhibited by approximately 50%. Two additional mutants, R55C (at the B/C junction) and R6H (in the signal peptide), were normally targeted to secretory granules, but nonetheless caused substantial ER stress. CONCLUSIONS: We describe three INS mutations cosegregating with early-onset diabetes whose clinical presentation is compatible with MODY. These led to the production of (pre)proinsulin molecules with markedly different trafficking properties and effects on ER stress, demonstrating a range of molecular defects in the beta-cell.


Assuntos
Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Retículo Endoplasmático/metabolismo , Proinsulina/genética , Proinsulina/metabolismo , Adolescente , Adulto , Idade de Início , Saúde da Família , Feminino , França , Proteínas de Fluorescência Verde/genética , Heterozigoto , Humanos , Células Secretoras de Insulina/fisiologia , Masculino , Mutagênese Sítio-Dirigida , Linhagem , Mutação Puntual , Proinsulina/química , Dobramento de Proteína , Estrutura Terciária de Proteína , Transporte Proteico/fisiologia , RNA Mensageiro/metabolismo , Estresse Fisiológico/fisiologia , Adulto Jovem
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