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1.
Appetite ; 162: 105174, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33636216

RESUMO

Previous studies have suggested that infant rapid weight change can be associated with an increased weight later in life. However, the weight change trajectory in early life over time and which childhood lifestyle behaviors may modify the risk of rapid weight change have not been characterized. Using our ongoing birth cohort study, we have addressed these issues. Nine follow-up time points (birth, 3, 6, 9, 12, 18, 24, 36, and 48 months) were used to calculate the change between two adjacent weight-for-age z-scores (WAZ-change), and then WAZ-change trajectories were defined via group-based trajectory modeling. The solitary, independent and combined effects of WAZ-change trajectories and each lifestyle factor (eating behaviors, physical activity, media exposure time and total sleep duration) on childhood adiposity measures at age 4 years were determined using multivariate regression analysis. Overall, 84 (38%) children had a steady growth trajectory from birth to 4 years, while the other 137 (62%) children had an early infancy rapid growth trajectory, particularly in the first three months. Compared to children with steady growth, children with early infancy rapid growth had a significantly higher body mass index, waist circumference, and subcutaneous fat. Moreover, weight change trajectory and three eating behaviors (i.e. food responsiveness, satiety responsiveness and food fussiness), not only had independent effects, but also combined (synergistic) effects on the majority of adiposity measures. Our results extend the current literature and provide a potentially valuable model to aid clinicians and health professionals in designing early-life interventions targeting specific populations, specific ages and specific lifestyle behaviors to prevent childhood overweight/obesity.


Assuntos
Trajetória do Peso do Corpo , Obesidade Infantil , Adiposidade , Peso ao Nascer , Índice de Massa Corporal , Criança , Pré-Escolar , Estudos de Coortes , Comportamento Alimentar , Feminino , Humanos , Lactente , Fatores de Risco
2.
Brain ; 142(11): 3382-3397, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31637422

RESUMO

CTP:phosphoethanolamine cytidylyltransferase (ET), encoded by PCYT2, is the rate-limiting enzyme for phosphatidylethanolamine synthesis via the CDP-ethanolamine pathway. Phosphatidylethanolamine is one of the most abundant membrane lipids and is particularly enriched in the brain. We identified five individuals with biallelic PCYT2 variants clinically characterized by global developmental delay with regression, spastic para- or tetraparesis, epilepsy and progressive cerebral and cerebellar atrophy. Using patient fibroblasts we demonstrated that these variants are hypomorphic, result in altered but residual ET protein levels and concomitant reduced enzyme activity without affecting mRNA levels. The significantly better survival of hypomorphic CRISPR-Cas9 generated pcyt2 zebrafish knockout compared to a complete knockout, in conjunction with previously described data on the Pcyt2 mouse model, indicates that complete loss of ET function may be incompatible with life in vertebrates. Lipidomic analysis revealed profound lipid abnormalities in patient fibroblasts impacting both neutral etherlipid and etherphospholipid metabolism. Plasma lipidomics studies also identified changes in etherlipids that have the potential to be used as biomarkers for ET deficiency. In conclusion, our data establish PCYT2 as a disease gene for a new complex hereditary spastic paraplegia and confirm that etherlipid homeostasis is important for the development and function of the brain.


Assuntos
Fosfatidiletanolaminas/biossíntese , RNA Nucleotidiltransferases/genética , Paraplegia Espástica Hereditária/genética , Adolescente , Alelos , Animais , Atrofia , Encéfalo/patologia , Criança , Pré-Escolar , Deficiências do Desenvolvimento/genética , Epilepsia/genética , Feminino , Técnicas de Inativação de Genes , Variação Genética , Humanos , Lipidômica , Masculino , Camundongos , RNA Nucleotidiltransferases/deficiência , Adulto Jovem , Peixe-Zebra
3.
Am J Hum Genet ; 98(2): 363-72, 2016 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-26833329

RESUMO

Genetic studies of intellectual disability and identification of monogenic causes of obesity in humans have made immense contribution toward the understanding of the brain and control of body mass. The leptin > melanocortin > SIM1 pathway is dysregulated in multiple monogenic human obesity syndromes but its downstream targets are still unknown. In ten individuals from six families, with overlapping 6q16.1 deletions, we describe a disorder of variable developmental delay, intellectual disability, and susceptibility to obesity and hyperphagia. The 6q16.1 deletions segregated with the phenotype in multiplex families and were shown to be de novo in four families, and there was dramatic phenotypic overlap among affected individuals who were independently ascertained without bias from clinical features. Analysis of the deletions revealed a ∼350 kb critical region on chromosome 6q16.1 that encompasses a gene for proneuronal transcription factor POU3F2, which is important for hypothalamic development and function. Using morpholino and mutant zebrafish models, we show that POU3F2 lies downstream of SIM1 and controls oxytocin expression in the hypothalamic neuroendocrine preoptic area. We show that this finding is consistent with the expression patterns of POU3F2 and related genes in the human brain. Our work helps to further delineate the neuro-endocrine control of energy balance/body mass and demonstrates that this molecular pathway is conserved across multiple species.


Assuntos
Proteínas de Homeodomínio/genética , Deficiência Intelectual/genética , Obesidade/genética , Fatores do Domínio POU/genética , Deleção de Sequência , Adolescente , Adulto , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Índice de Massa Corporal , Linhagem Celular , Criança , Pré-Escolar , Cromossomos Humanos Par 6/genética , Modelos Animais de Doenças , Metabolismo Energético , Feminino , Proteínas de Homeodomínio/metabolismo , Humanos , Hipotálamo/metabolismo , Masculino , Pessoa de Meia-Idade , Ocitocina/metabolismo , Fatores do Domínio POU/metabolismo , Linhagem , Fenótipo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Adulto Jovem , Peixe-Zebra
4.
J Med Genet ; 53(9): 634-41, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27091925

RESUMO

BACKGROUND: Isolated Complex I deficiency is the most common paediatric mitochondrial disease presentation, associated with poor prognosis and high mortality. Complex I comprises 44 structural subunits with at least 10 ancillary proteins; mutations in 29 of these have so far been associated with mitochondrial disease but there are limited genotype-phenotype correlations to guide clinicians to the correct genetic diagnosis. METHODS: Patients were analysed by whole-exome sequencing, targeted capture or candidate gene sequencing. Clinical phenotyping of affected individuals was performed. RESULTS: We identified a cohort of 10 patients from 8 families (7 families are of unrelated Irish ancestry) all of whom have short stature (<9th centile) and similar facial features including a prominent forehead, smooth philtrum and deep-set eyes associated with a recurrent homozygous c.64T>C, p.Trp22Arg NDUFB3 variant. Two sibs presented with primary short stature without obvious metabolic dysfunction. Analysis of skeletal muscle from three patients confirmed a defect in Complex I assembly. CONCLUSIONS: Our report highlights that the long-term prognosis related to the p.Trp22Arg NDUFB3 mutation can be good, even for some patients presenting in acute metabolic crisis with evidence of an isolated Complex I deficiency in muscle. Recognition of the distinctive facial features-particularly when associated with markers of mitochondrial dysfunction and/or Irish ancestry-should suggest screening for the p.Trp22Arg NDUFB3 mutation to establish a genetic diagnosis, circumventing the requirement of muscle biopsy to direct genetic investigations.


Assuntos
Nanismo/genética , Complexo I de Transporte de Elétrons/genética , Mitocôndrias/genética , Doenças Mitocondriais/genética , Mutação/genética , Criança , Pré-Escolar , Exoma/genética , Fácies , Feminino , Estudos de Associação Genética/métodos , Homozigoto , Humanos , Lactente , Masculino , Linhagem , Fenótipo
5.
Am J Hum Genet ; 92(1): 131-6, 2013 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-23273570

RESUMO

Next-generation sequencing (NGS) enables analysis of the human genome on a scale previously unachievable by Sanger sequencing. Exome sequencing of the coding regions and conserved splice sites has been very successful in the identification of disease-causing mutations, and targeting of these regions has extended clinical diagnostic testing from analysis of fewer than ten genes per phenotype to more than 100. Noncoding mutations have been less extensively studied despite evidence from mRNA analysis for the existence of deep intronic mutations in >20 genes. We investigated individuals with hyperinsulinaemic hypoglycaemia and biochemical or genetic evidence to suggest noncoding mutations by using NGS to analyze the entire genomic regions of ABCC8 (117 kb) and HADH (94 kb) from overlapping ~10 kb PCR amplicons. Two deep intronic mutations, c.1333-1013A>G in ABCC8 and c.636+471G>T HADH, were identified. Both are predicted to create a cryptic splice donor site and an out-of-frame pseudoexon. Sequence analysis of mRNA from affected individuals' fibroblasts or lymphoblastoid cells confirmed mutant transcripts with pseudoexon inclusion and premature termination codons. Testing of additional individuals showed that these are founder mutations in the Irish and Turkish populations, accounting for 14% of focal hyperinsulinism cases and 32% of subjects with HADH mutations in our cohort. The identification of deep intronic mutations has previously focused on the detection of aberrant mRNA transcripts in a subset of disorders for which RNA is readily obtained from the target tissue or ectopically expressed at sufficient levels. Our approach of using NGS to analyze the entire genomic DNA sequence is applicable to any disease.


Assuntos
3-Hidroxiacil-CoA Desidrogenases/genética , Transportadores de Cassetes de Ligação de ATP/genética , Hiperinsulinismo/genética , Mutação , Canais de Potássio Corretores do Fluxo de Internalização/genética , Receptores de Droga/genética , Linhagem Celular , Éxons , Humanos , Íntrons , Masculino , Sítios de Splice de RNA , Análise de Sequência de DNA , Receptores de Sulfonilureias
6.
Am J Hum Genet ; 92(4): 605-13, 2013 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-23541340

RESUMO

Perrault syndrome is a genetically and clinically heterogeneous autosomal-recessive condition characterized by sensorineural hearing loss and ovarian failure. By a combination of linkage analysis, homozygosity mapping, and exome sequencing in three families, we identified mutations in CLPP as the likely cause of this phenotype. In each family, affected individuals were homozygous for a different pathogenic CLPP allele: c.433A>C (p.Thr145Pro), c.440G>C (p.Cys147Ser), or an experimentally demonstrated splice-donor-site mutation, c.270+4A>G. CLPP, a component of a mitochondrial ATP-dependent proteolytic complex, is a highly conserved endopeptidase encoded by CLPP and forms an element of the evolutionarily ancient mitochondrial unfolded-protein response (UPR(mt)) stress signaling pathway. Crystal-structure modeling suggests that both substitutions would alter the structure of the CLPP barrel chamber that captures unfolded proteins and exposes them to proteolysis. Together with the previous identification of mutations in HARS2, encoding mitochondrial histidyl-tRNA synthetase, mutations in CLPP expose dysfunction of mitochondrial protein homeostasis as a cause of Perrault syndrome.


Assuntos
Proteases Dependentes de ATP/genética , Endopeptidase Clp/genética , Exoma/genética , Genes Recessivos , Disgenesia Gonadal 46 XX/etiologia , Perda Auditiva Neurossensorial/etiologia , Mitocôndrias/enzimologia , Mutação/genética , Proteases Dependentes de ATP/metabolismo , Trifosfato de Adenosina/metabolismo , Adolescente , Adulto , Feminino , Homozigoto , Humanos , Hibridização In Situ , Masculino , Mitocôndrias/genética , Linhagem , Fenótipo , Adulto Jovem
7.
Pediatr Res ; 80(2): 299-305, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27057740

RESUMO

BACKGROUND: Later life metabolic dysfunction is a well-recognized consequence of being born small for gestational age (SGA). This study has applied metabolomics to identify whether there are changes in these pathways in prepubertal short SGA children and aimed to compare the intracellular and extracellular metabolome in fibroblasts derived from healthy children and SGA children with postnatal growth impairment. METHODS: Skin fibroblast cell lines were established from eight SGA children (age 1.8-10.3 y) with failure of catch-up growth and from three healthy control children. Confluent cells were incubated in serum-free media and the spent growth medium (metabolic footprint), and intracellular metabolome (metabolic fingerprint) were analyzed by gas-chromatography mass spectrometry. RESULTS: Nineteen metabolites were significantly altered between SGA and control cell lines. The greatest fold difference (FD) was seen for alanine (fingerprint FD, SGA: control 0.3, P = 0.01 and footprint FD = 0.19, P = 0.01), aspartic acid (fingerprint FD = 5.21, P = 0.01), and cystine (footprint FD = 1.66, P = 0.02). Network analysis of the differentially expressed metabolites predicted inhibition of insulin as well as growth (ERK) signaling in SGA cells. CONCLUSION: This study indicates that changes in cellular metabolism associated with both growth failure and insulin insensitivity are present in prepubertal short children born SGA.


Assuntos
Aminoácidos/metabolismo , Glicólise , Transtornos do Crescimento/sangue , Recém-Nascido Pequeno para a Idade Gestacional , Alanina/metabolismo , Ácido Aspártico/metabolismo , Estatura , Criança , Pré-Escolar , Feminino , Fibroblastos/metabolismo , Idade Gestacional , Transtornos do Crescimento/complicações , Homozigoto , Humanos , Lactente , Insulina/metabolismo , Resistência à Insulina , Masculino , Metaboloma , Metabolômica , Mutação , Pele/metabolismo
8.
J Pediatr ; 166(1): 191-4, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25444530

RESUMO

Congenital hyperinsulinism causes profound hypoglycemia, which may persist or resolve spontaneously. Among 13 children with congenital hyperinsulinism, elevated incretin hormone concentrations were detected in 2 with atypical, persistent disease. We suggest that incretin biomarkers may identify these patients, and that elevated hormone levels may contribute to their pathophysiology.


Assuntos
Biomarcadores/sangue , Hiperinsulinismo Congênito/sangue , Incretinas/sangue , Canais KATP/genética , Pré-Escolar , Hiperinsulinismo Congênito/genética , Humanos , Lactente , Recém-Nascido , Mutação , Reino Unido
9.
Am J Hum Genet ; 89(1): 148-53, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21737058

RESUMO

3-M syndrome, a primordial growth disorder, is associated with mutations in CUL7 and OBSL1. Exome sequencing now identifies mutations in CCDC8 as a cause of 3-M syndrome. CCDC8 is a widely expressed gene that is transcriptionally associated to CUL7 and OBSL1, and coimmunoprecipitation indicates a physical interaction between CCDC8 and OBSL1 but not CUL7. We propose that CUL7, OBSL1, and CCDC8 are members of a pathway controlling mammalian growth.


Assuntos
Proteínas Culina/genética , Proteínas do Citoesqueleto/genética , Nanismo/genética , Deficiência Intelectual/genética , Hipotonia Muscular/genética , Linhagem Celular , Pré-Escolar , Proteínas Culina/metabolismo , Proteínas do Citoesqueleto/metabolismo , Feminino , Expressão Gênica , Homozigoto , Humanos , Lactente , Masculino , Mutação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Coluna Vertebral/anormalidades , Fatores de Transcrição
10.
Nat Genet ; 37(10): 1119-24, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16142236

RESUMO

Intrauterine growth retardation is caused by maternal, fetal or placental factors that result in impaired endovascular trophoblast invasion and reduced placental perfusion. Although various causes of intrauterine growth retardation have been identified, most cases remain unexplained. Studying 29 families with 3-M syndrome (OMIM 273750), an autosomal recessive condition characterized by severe pre- and postnatal growth retardation, we first mapped the underlying gene to chromosome 6p21.1 and then identified 25 distinct mutations in the gene cullin 7 (CUL7). CUL7 assembles an E3 ubiquitin ligase complex containing Skp1, Fbx29 (also called Fbw8) and ROC1 and promotes ubiquitination. Using deletion analysis, we found that CUL7 uses its central region to interact with the Skp1-Fbx29 heterodimer. Functional studies indicated that the 3-M-associated CUL7 nonsense and missense mutations R1445X and H1464P, respectively, render CUL7 deficient in recruiting ROC1. These results suggest that impaired ubiquitination may have a role in the pathogenesis of intrauterine growth retardation in humans.


Assuntos
Cromossomos Humanos Par 6/genética , Proteínas Culina/genética , Retardo do Crescimento Fetal/genética , Proteínas de Transporte/metabolismo , Criança , Mapeamento Cromossômico , Códon sem Sentido , Análise Mutacional de DNA , Feminino , Homozigoto , Humanos , Masculino , Mutação de Sentido Incorreto , Mapeamento de Interação de Proteínas , Estrutura Terciária de Proteína , Proteínas Quinases Associadas a Fase S/metabolismo , Proteínas Ligases SKP Culina F-Box/metabolismo , Deleção de Sequência , Síndrome
11.
Am J Med Genet C Semin Med Genet ; 163C(2): 76-85, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23613426

RESUMO

Human growth is a complex process starting at conception and completing in adolescence at the time of growth plate fusion. Growth can be divided into four phases: (1) fetal, where the predominant endocrine factors controlling growth are insulin and the insulin-like growth factors. (2) Infancy, where growth is mainly dependent upon nutrition. (3) Childhood, where the growth hormone-insulin-like growth factor-I (GH-IGF-I) axis and thyroid hormone are most important. (4) Puberty, where along with the GH-IGF-I axis the activation of the hypothalamo-pituitary-gonadal axis to generate sex steroid secretion becomes vital to the completion of growth. GH is released from the pituitary in a pulsatile fashion under the control of GHRH, Ghrelin, and somatostatin and, via a complex signal transduction cascade, initiates the release of IGF-I within many tissues but predominantly the liver and at the growth plate. IGF-I acts in an autocrine and paracrine manner via the IGF-I receptor to stimulate cell proliferation and longitudinal growth. Activation of the pituitary-gonadal axis during puberty occurs via a complex interaction of factors including kisspeptin, leptin, gonadotrophin releasing hormone, and tachykinin ultimately leading to augmentation of GH secretion, the pubertal growth spurt, and fusion of the growth plates. Many other hormones can affect the GH-IGF-I system or directly affect cell proliferation at the growth plate including thyroid hormone, vitamin D, and corticosteroids.


Assuntos
Glândulas Endócrinas/fisiologia , Crescimento/fisiologia , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Puberdade
12.
Clin Endocrinol (Oxf) ; 78(1): 23-8, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23009615

RESUMO

BACKGROUND: Congenital adrenal hyperplasia (CAH) has implications throughout a patient's life. The challenges of organizing transition from paediatric to adult care in endocrinology are recognized. OBJECTIVE: To evaluate whether young people with CAH have been successfully transitioned from paediatric care to specialist adult services and the influence of the introduction of a Young Person Clinic (YPC) where the young person is introduced to the adult endocrinologist. DESIGN, PATIENTS AND MEASUREMENTS: Patients aged 16+ years with CAH who had attended the adrenal clinic at Royal Manchester Children's Hospital between 1992 and 2009 were identified. Clinical information, attendance data in paediatric and adult services were obtained from patient records and the electronic appointment system. RESULTS: A total of 61 patients (27 men) were identified. Thirty-six patients were referred to specialist adult services from the paediatric service; eighteen of these (50%) were lost to follow-up (two were never offered an appointment). Only 53% of the whole group attended their first new and subsequent second appointment (i.e. good early attenders). There was no difference in engagement with adult services in those who transitioned through the YPC. Good early attenders were less likely to get lost to follow-up compared with poor early attenders (11-33% lost to follow-up compared with 63-71%). CONCLUSIONS: Half of all young people with CAH referred to specialist adult services are no longer attending. Introducing the adult endocrinologist prior to transfer had no positive effect on engagement with adult services. Attendance at the first two appointments in the adult services should be seen as an indicator of 'reasonable' engagement.


Assuntos
Hiperplasia Suprarrenal Congênita , Transição para Assistência do Adulto , Adolescente , Adulto , Atenção à Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pediatria , Adulto Jovem
13.
Clin Endocrinol (Oxf) ; 78(1): 29-35, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22734661

RESUMO

OBJECTIVE: Transition from child to adult status is a crucial stage in young people's lives. It is important that young people continue to receive appropriate endocrine care throughout and following transfer from paediatric to adult services. This study examined indicators of patient loss to follow-up at initial transfer from paediatric care to identify implications for transitional care practice and research. METHODS: A retrospective analysis of patient data following transfer from paediatric services to a young person's transition clinic was conducted. Attendance data from 103 patients transferred to the Young Person's Clinic were analysed to determine the factors affecting nonattendance 1-year post-transfer. RESULTS: We found that overall one quarter of patients did not attend the young person's clinic in the first year after transfer. Those with poor attendance prior to transfer were likely to be poor attenders post-transfer. Further, those without an appointment scheduled in the first 6 months of their final paediatric transfer appointment were less likely to attend in the first year. CONCLUSIONS: Young people are at risk of losing contact during the transfer from paediatric to the young person's clinic. Measures that promote continuity of contact could reduce the risk of long-term disengagement with care. Further development and research is required to identify the best ways to help young people with endocrine conditions in the transition from child to adult status.


Assuntos
Continuidade da Assistência ao Paciente , Endocrinologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
14.
Am J Epidemiol ; 175(9): 867-77, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22494952

RESUMO

Recombinant human growth hormone (rhGH) therapy is used in the long-term treatment of children with growth disorders, but there is considerable treatment response variability. The exon 3-deleted growth hormone receptor polymorphism (GHR(d3)) may account for some of this variability. The authors performed a systematic review (to April 2011), including investigator-only data, to quantify the effects of the GHR(fl-d3) and GHR(d3-d3) genotypes on rhGH therapy response and used a recently established Bayesian inheritance model-free approach to meta-analyze the data. The primary outcome was the 1-year change-in-height standard-deviation score for the 2 genotypes. Eighteen data sets from 12 studies (1,527 children) were included. After several prior assumptions were tested, the most appropriate inheritance model was codominant (posterior probability = 0.93). Compared with noncarriers, carriers had median differences in 1-year change-in-height standard-deviation score of 0.09 (95% credible interval (CrI): 0.01, 0.17) for GHR(fl-d3) and of 0.14 (95% CrI: 0.02, 0.26) for GHR(d3-d3). However, the between-study standard deviation of 0.18 (95% CrI: 0.10, 0.33) was considerable. The authors tested by meta-regression for potential modifiers and found no substantial influence. They conclude that 1) the GHR(d3) polymorphism inheritance is codominant, contrasting with previous reports; 2) GHR(d3) genotypes account for modest increases in rhGH effects in children; and 3) considerable unexplained variability in responsiveness remains.


Assuntos
Proteínas de Transporte/genética , Transtornos do Crescimento/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Modelos Genéticos , Teorema de Bayes , Criança , Heterogeneidade Genética , Humanos , Polimorfismo Genético , Viés de Publicação
15.
Am J Hum Genet ; 84(6): 801-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19481195

RESUMO

3-M syndrome is an autosomal-recessive primordial growth disorder characterized by significant intrauterine and postnatal growth restriction. Mutations in the CUL7 gene are known to cause 3-M syndrome. In 3-M syndrome patients that do not carry CUL7 mutations, we performed high-density genome-wide SNP mapping to identify a second locus at 2q35-q36.1. Further haplotype analysis revealed a 1.29 Mb interval in which the underlying gene is located and we subsequently discovered seven distinct null mutations from 10 families within the gene OBSL1. OBSL1 is a putative cytoskeletal adaptor protein that localizes to the nuclear envelope. We were also able to demonstrate that loss of OBSL1 leads to downregulation of CUL7, implying a role for OBSL1 in the maintenance of CUL7 protein levels and suggesting that both proteins are involved within the same molecular pathway.


Assuntos
Proteínas do Citoesqueleto/genética , Transtornos do Crescimento/genética , Mutação/genética , Polimorfismo de Nucleotídeo Único/genética , Ubiquitinação , Adolescente , Células Cultivadas , Criança , Pré-Escolar , Proteínas Culina/genética , Proteínas do Citoesqueleto/antagonistas & inibidores , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto , Feminino , Humanos , Lactente , Rim/citologia , Rim/metabolismo , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Linhagem , RNA Interferente Pequeno/farmacologia , Síndrome
16.
Clin Endocrinol (Oxf) ; 77(3): 335-42, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22624670

RESUMO

3-M syndrome is an autosomal recessive primordial growth disorder characterized by small birth size and post-natal growth restriction associated with a spectrum of minor anomalies (including a triangular-shaped face, flat cheeks, full lips, short chest and prominent fleshy heels). Unlike many other primordial short stature syndromes, intelligence is normal and there is no other major system involvement, indicating that 3-M is predominantly a growth-related condition. From an endocrine perspective, serum GH levels are usually normal and IGF-I normal or low, while growth response to rhGH therapy is variable but typically poor. All these features suggest a degree of resistance in the GH-IGF axis. To date, mutations in three genes CUL7, OBSL1 and CCDC8 have been shown to cause 3-M. CUL7 acts an ubiquitin ligase and is known to interact with p53, cyclin D-1 and the growth factor signalling molecule IRS-1, the link with the latter may contribute to the GH-IGF resistance. OBSL1 is a putative cytoskeletal adaptor that interacts with and stabilizes CUL7. CCDC8 is the newest member of the pathway and interacts with OBSL1 and, like CUL7, associates with p53, acting as a co-factor in p53-medicated apoptosis. 3-M patients without a mutation have also been identified, indicating the involvement of additional genes in the pathway. Potentially damaging sequence variants in CUL7 and OBSL1 have been identified in idiopathic short stature (ISS), including those born small with failure of catch-up growth, signifying that the 3-M pathway could play a wider role in disordered growth.


Assuntos
Nanismo/diagnóstico , Hipotonia Muscular/diagnóstico , Proteínas de Transporte/genética , Criança , Proteínas Culina/genética , Proteínas do Citoesqueleto/genética , Diagnóstico Diferencial , Nanismo/tratamento farmacológico , Nanismo/genética , Nanismo/metabolismo , Feminino , Retardo do Crescimento Fetal/genética , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Masculino , Redes e Vias Metabólicas , Hipotonia Muscular/tratamento farmacológico , Hipotonia Muscular/genética , Hipotonia Muscular/metabolismo , Mutação , Gravidez , Síndrome de Silver-Russell/diagnóstico , Síndrome de Silver-Russell/genética , Coluna Vertebral/anormalidades , Coluna Vertebral/metabolismo , Ubiquitinação
17.
Malar J ; 11: 75, 2012 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-22429464

RESUMO

BACKGROUND: Malaria is more common in pregnant than in non-pregnant Nigerian women, and is associated with small birth size and the attendant short- and long-term health risks. The influence of malaria on maternal metabolic status in pregnancy and in cord blood and how this relates to birth size has not been studied. The study objective was to define relationships between maternal and cord serum metabolic markers, maternal malaria status and birth size. METHODS: During pregnancy, anthropometric measurements, blood film for malaria parasites and assays for lipids, glucose, insulin and TNF were obtained from 467 mothers and these analytes and insulin-like growth factor-I (IGF-I) were obtained from cord blood of 187 babies. RESULTS: Overall prevalence of maternal malaria was 52%, associated with younger age, anaemia and smaller infant birth size. Mothers with malaria had significantly lower cholesterol (total, HDL and LDL) and higher TNF, but no difference in triglyceride. In contrast, there was no effect of maternal malaria on cord blood lipids, but the median (range) cord IGF-I was significantly lower in babies whose mothers had malaria: 60.4 (24, 145) µg/L, versus no malaria: 76.5 (24, 150) µg/L, p = 0.03. On regression analysis, the key determinants of birth weight included maternal total cholesterol, malarial status and cord insulin and IGF-I. CONCLUSIONS: Malaria in pregnancy was common and associated with reduced birth size, lower maternal lipids and higher TNF. In the setting of endemic malaria, maternal total cholesterol during pregnancy and cord blood insulin and IGF-I levels are potential biomarkers of foetal growth and birth size.


Assuntos
Biomarcadores/sangue , Sangue Fetal/química , Malária Falciparum/metabolismo , Plasmodium falciparum/fisiologia , Complicações Parasitárias na Gravidez/metabolismo , Adolescente , Adulto , Glicemia/análise , Feminino , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Lipoproteínas/sangue , Malária Falciparum/parasitologia , Pessoa de Meia-Idade , Nigéria , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Fator de Necrose Tumoral alfa/sangue
18.
Curr Res Physiol ; 5: 216-223, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35637870

RESUMO

Respirometry, based on oxygen uptake, is commonly employed for measuring metabolic rate. There is a growing need for metabolic rate measurements suitable for developmental studies, particularly in Danio rerio, where many important developmental stages occur at < 4 mm. However, respirometry becomes more challenging as the size of the organism reduces. Additionally, respirometry can be costly and require significant experience and technical knowledge which may prohibit uptake in non-specialist/non-physiology labs. Thus, using equipment routine in most developmental/molecular biology laboratories, we measured glucose uptake in 96-h post fertilisation (hpf) zebrafish larvae and compared it to stop-flow respirometry measures of oxygen uptake to test whether glucose uptake was a suitable alternative measure of metabolic rate. A Passing-Bablok regression revealed that within a 95% limit of agreement, the rate of glucose uptake and the rate of oxygen uptake were equivalent as measures of metabolic rate in 96 hpf Danio rerio larvae. Thus, the methodology we outline here may be a useful alternative or a complementary method for assessing metabolic rate in small organisms.

19.
J Endocr Soc ; 6(3): bvac006, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35178492

RESUMO

CONTEXT: Single-nucleotide polymorphisms (SNPs) in ZBTB38 have been associated with idiopathic short stature (ISS) and adult height. OBJECTIVE: This study sought to (a) characterize the phenotype of ISS patients and their response to recombinant human growth hormone (rhGH) by ZBTB38 SNP genotype; (b) describe the relationship of ZBTB38 expression with normal growth; and (c) describe the in vitro effects of ZBTB38 knockdown on cell proliferation and MCM10 expression. METHODS: The genotype-phenotype relationship of rs6764769 and rs724016 were explored in 261 ISS patients and effects of genotype on response to rhGH were assessed in 93 patients treated with rhGH. The relationship between age and ZBTB38 expression was assessed in 87 normal children and young adults. Knockdown of ZBTB38 in SiHA cells was achieved with siRNAs and cell proliferation assessed with a WST-8 assay. RESULTS: We found that rs6764769 and rs724016 are in linkage disequilibrium. The rs724016 GG genotype was associated with lower birth length (P = 0.01) and a lower change in height SDS over the first year of treatment (P = 0.02). ZBTB38 expression was positively correlated with age (P < 0.001). siRNA-mediated knockdown of ZBTB38 resulted in increased cell proliferation at 72 and 96 hours posttransfection but did not alter expression of MCM10. CONCLUSIONS: SNPs within ZBTB38 associated with ISS are linked to higher birth size within a cohort of ISS patients and a better response to rhGH therapy while ZBTB38 expression is positively related to age.

20.
J Clin Endocrinol Metab ; 107(12): 3287-3301, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36102184

RESUMO

CONTEXT: The Kabi/Pfizer International Growth Database (KIGS) is a large, international database (1987-2012) of children treated with recombinant human growth hormone (rhGH) in real-world settings. OBJECTIVE: This work aimed to evaluate the safety and efficacy of rhGH from the full KIGS cohort. METHODS: Data were collected by investigators from children with growth disorders treated with rhGH (Genotropin [somatropin]; Pfizer). Safety was evaluated in all treated patients, and efficacy in those treated for 1 year or more. A subgroup included patients treated for 5 years or more (≥ 2 years prepubertal) who had reached near-adult height (NAH). Main outcomes included adverse events (AEs), serious AEs (SAEs), and height growth. RESULTS: The full KIGS cohort (N = 83 803 [58% male]) was treated for idiopathic GH deficiency (IGHD; 46.9%), organic GHD (10.0%), small for gestational age (SGA; 9.5%), Turner syndrome (TS; 9.2%), idiopathic short stature (ISS; 8.2%), and others (16.2%). Median rhGH treatment duration was 2.7 years and observation 3.1 years. SAEs occurred in 3.7% of patients and death in 0.4%. The most common SAEs were recurrence of craniopharyngioma (n = 151), neoplasm (n = 99), and cancer (n = 91); and scoliosis (n = 91). Median first-year delta height-SD score (SDS) (Prader) in prepubertal patients was 0.66 (IGHD), 0.55 (ISS), 0.58 (TS), and 0.71 (SGA). Median gains in NAH-SDS were 1.79 (IGHD), 1.37 (ISS), and 1.34 (SGA) for boys, and 2.07 (IGHD), 1.62 (ISS), 1.07 (TS), and 1.57 (SGA) for girls. CONCLUSION: Data from KIGS, the largest and longest running international database of rhGH-treated children, show that rhGH is safe and increases short-term height gain and adult height across GHD and non-GHD conditions.


Assuntos
Nanismo Hipofisário , Hormônio do Crescimento Humano , Adulto , Feminino , Criança , Humanos , Masculino , Hormônio do Crescimento Humano/efeitos adversos , Hormônio do Crescimento , Transtornos do Crescimento/tratamento farmacológico , Estatura , Proteínas Recombinantes/efeitos adversos
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