RESUMO
Resumen El objetivo del trabajo fue evaluar el funcionamiento cognitivo de niños y adolescentes con diabetes mellitus tipo 1 (DM1) de la consulta de Endocrinología del IAHULA, y compararlo al de niños no diabéticos, así como investigar la posible influencia de factores relacionados con la enfermedad sobre la cognición. Se realizó un estudio observacional analítico, transversal, que incluyó un grupo de 30 pacientes con DM1 de 8 a 16 años de edad (16 varones) y un grupo control de 30 individuos pareados por edad, género, escolaridad y condición socioeconómica. Se realizó interrogatorio y revisión de historias clínicas para obtener datos sobre las características clínicas y el tratamiento de la DM1. Se les aplicó el test WISC IV para evaluar cognición y cociente intelectual (CI). La edad promedio de los pacientes fue de 13,27 ± 2,31 años, la mitad de ellos masculinos. Se encontraron puntajes menores en los distintos dominios del WISC IV en el grupo con DM1 al compararlos con los del grupo control (p<0,01). El CI fue menor en los niños con DM1 que en los controles (75,47 ± 13,87 frente a 88,57±11,06; p=0,0001); así mismo, se observó con mayor frecuencia un puntaje del CI inferior al percentil 10 en los pacientes con DM1 en comparación con los controles (63,3% frente a 33,3%; p=0,02; Odds ratio: 3,45; IC95%: 1,19-9,99). Se concluyó que la DM1 impacta negativamente el desempeño cognitivo de niños y adolescentes. Se recomienda la evaluación cognitiva de estos pacientes, ya que podría repercutir en su vida diaria.
Abstract The study aimed to evaluate the cognitive functioning of children and adolescents with type 1 diabetes mellitus (T1DM) recruited from the IAHULA Endocrinology Outpatient Unit and to compare it to that of non-diabetics as to investigate the influence on cognition of factors related to the disease. An analytical, cross-sectional observational study was carried out on a group of 30 patients with T1DM between 8 and 16 years of age and on a control group of 30 individuals matched by age, gender, education, and socioeconomic status. Interrogation and review of medical records to obtain data on the clinical characteristics and treatment of T1DM were conducted. The WISC IV test was then applied to evaluate cognition and intellectual coefficient (IQ). The average age of the diabetic patients was 13.27±2.31 years, and half of them were male. Lower scores were found in the different domains of the WISC IV in the group with T1DM (p<0.01). The IQ was found to be lower in children with T1DM than in controls (75.47±13.87 vs. 88.57±11.06; p=0.0001). Likewise, a higher frequency of IQ scores below the 10th percentile was observed in the diabetic children (63.3% vs. 33.3%; p=0.02; Odds ratio: 3.45; 95%CI: 1.19-9.99). It was concluded that T1DM negatively impacts the cognitive performance of children and adolescents. Cognitive evaluation of these patients is recommended, as it could affect their daily life.
RESUMO
BACKGROUND AND PURPOSE: Metabolic syndrome (MetS) is a disorder associated with an increased risk of cardiovascular disease. The frequency of each component of MetS in Turner syndrome (TS) subjects is high. An elevated incidence of hearing loss has also been reported in TS. Sensorineural hearing loss (SNHL) affects at least half of young women with TS. The association between MetS and SNHL has not been previously considered in TS. The aim of this study is to evaluate the association between these two conditions. PATIENTS AND METHODS: Cross-sectional anthropometric, cardio-metabolic and audiological data were obtained from a cohort consisting of unrelated TS subjects (>20 years of age; n = 93). Metabolic syndrome was deï¬ned according to the International Diabetes Federation criteria. Types and severity of hearing loss were based on the American Speech Hearing Association guidelines. RESULTS: Hearing loss was detected in 74% of ears from adult TS subjects and SNHL was observed in half of our TS subjects. The prevalence of MetS in TS subjects with or without SNHL was 64% and 11%, respectively (P < 0.05). After adjusting for age, MetS was related to a ninefold increase in the odds of SNHL. This odds increased in a stepwise manner as the number of MetS components increased. CONCLUSION: MetS and its individual components were associated factors for SNHL in TS subjects. A reduction in the number and severity of the components of MetS might potentially contribute to decreasing the progression of SNHL at younger ages, but further studies will be needed to explain the underlying pathological mechanism connecting MetS and SNHL.
RESUMO
BACKGROUND AND PURPOSE: Excessive adiposity is associated with cardiometabolic complications in Turner syndrome (TS) subjects. Reference data for predictive anthropometric indices of overweight/obesity and metabolic syndrome (MetS) are lacking for subjects with TS. The purpose of this study was to identify the best anthropometric predictor of cardiometabolic risk in a Latin-American cohort of TS subjects. PATIENTS AND METHODS: This was a cross-sectional correlational study conducted in adult TS subjects (n=88) over the past seven years. Anthropometric parameters, body composition and biochemical variables were evaluated in a study and in a reference (n=57) group. Overweight/obesity and MetS were diagnosed using international consensus. The area under the ROC curve (AUC-ROC) was then used to determine the value of each anthropometric variable in predicting MetS or overweight/obesity. RESULTS: The prevalence of MetS and overweight/obesity in TS subjects was 40% and 48%, respectively. All anthropometric and cardiometabolic variables were significantly increased in TS subjects when compared to the reference group, except for body mass index (BMI) and HDL-c. To detect MetS and overweight/obesity, waist to height ratio (WHtR) was found to have a higher correlation with cardiometabolic variables (TC, LDL-c, HDL-c levels and the LDL-c/HDL-c ratio), and to have a higher AUC-ROC and odds ratio than BMI, waist circumference (WC) and the waist to hip ratio (WHR). CONCLUSION: The prevalence of MetS and overweight/obesity is elevated in TS subjects. WHtR was the most useful variable in predicting the presence of MetS and overweight and obesity in this TS cohort. A combination of WHtR with BMI or with WC could have the best clinical utility in identifying adult TS subjects with overweight/obesity and MetS, respectively.
RESUMO
OBJECTIVE: To understand whether spontaneous vs induced puberty and the type and route of estrogen influence the height of girls with Turner syndrome on growth hormone (GH). STUDY DESIGN: Search of an international database of children treated with GH revealed 772 girls with Turner syndrome followed from GH initiation to near adult height. Data from girls with sustained spontaneous puberty (n = 145) were compared with those requiring estrogens for induction or maintenance of puberty (n = 627). RESULTS: At GH start, mean age (7.5 vs 7.9 years), weight (-1.7 vs -1.7 SDS), and body mass index (0.2 SDS vs 0.1 SDS) were similar for girls with spontaneous puberty and with induced puberty. Although those girls with spontaneous puberty were shorter than those with induced puberty, when midparental height was taken into consideration, starting heights in both groups averaged -2.8 SDS. Both groups received approximately 0.3 mg/kg/week of GH. Girls with spontaneous puberty initiated puberty and reached near adult height earlier than girls with induced puberty (12.6 ± 1.8 years vs 13.4 ± 1.4 years and 16.0 ± 1.3 years vs 16.9 ± 1.4 years, respectively). Although girls with spontaneous puberty grew more in the first year of GH therapy and between the onset of puberty and near adult height (11.0 cm vs 9.3 cm), height SDS at near adult height and the length of time in puberty before reaching near adult height were comparable. A 45,X karyotype was detected in 22.1% of girls with spontaneous puberty and in 58.4% of girls with induced puberty. Patients receiving transdermal estrogens did not grow better than those on oral estrogens. Adverse event reporting was comparable between groups. CONCLUSIONS: Girls with Turner syndrome with spontaneous puberty tended to grow better in response to GH than girls with induced puberty, but not enough to produce a difference in height SDS at near adult height.
Assuntos
Estatura , Hormônio do Crescimento Humano/uso terapêutico , Puberdade , Síndrome de Turner/tratamento farmacológico , Adolescente , Adulto , Criança , Feminino , Humanos , Puberdade/efeitos dos fármacos , Puberdade/fisiologia , Síndrome de Turner/fisiopatologiaRESUMO
Background: Monosomy of the X chromosome is the most frequent genetic abnormality in human as it is present in approximately 2% of all conceptions, although 99% of these embryos are spontaneously miscarried. In postnatal life, clinical features of Turner syndrome may include typical dysmorphic stigmata, short stature, sexual infantilism, and renal, cardiac, skeletal, endocrine and metabolic abnormalities. Main text: Turner syndrome is due to a partial or total loss of the second sexual chromosome, resulting in the development of highly variable clinical features. This phenotype may not merely be due to genomic imbalance from deleted genes but may also result from additive influences on associated genes within a given gene network, with an altered regulation of gene expression triggered by the absence of the second sex chromosome. Current studies in human and mouse models have demonstrated that this chromosomal abnormality leads to epigenetic changes, including differential DNA methylation in specific groups of downstream target genes in pathways associated with several clinical and metabolic features, mostly on autosomal chromosomes. In this article, we begin exploring the potential involvement of both genetic and epigenetic factors in the origin of X chromosome monosomy. We review the dispute between the meiotic and post-zygotic origins of 45,X monosomy, by mainly analyzing the findings from several studies that compare gene expression of the 45,X monosomy to their euploid and/or 47,XXX trisomic cell counterparts on peripheral blood mononuclear cells, amniotic fluid, human fibroblast cells, and induced pluripotent human cell lines. From these studies, a profile of epigenetic changes seems to emerge in response to chromosomal imbalance. An interesting finding of all these studies is that methylation-based and expression-based pathway analyses are complementary, rather than overlapping, and are correlated with the clinical picture displayed by TS subjects. Conclusions: The clarification of these possible causal pathways may have future implications in increasing the life expectancy of these patients and may provide informative targets for early pharmaceutical intervention.
Assuntos
Cromossomos Humanos X/genética , Metilação de DNA , Redes Reguladoras de Genes , Síndrome de Turner/genética , Epigênese Genética , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Monossomia , TrissomiaRESUMO
Epigenetic mechanisms play an important role in the regulation of the Growth Hormone- Insulin-like Growth Factor 1 (GH-IGF1) axis and in processes for controlling long bone growth, and carbohydrate and lipid metabolism. Improvement of methodologies that allow for the assessment of epigenetic regulation have contributed enormously to the understanding of GH action, but many questions still remain to be clarified. The reversible nature of epigenetic factors and, particularly, their role as mediators between the genome and the environment, make them viable therapeutic target candidates. Rather than reviewing the molecular and epigenetic pathways regulated by GH action, in this review we have focused on the use of epigenetic modulators as potential drugs to improve the GH response. We first discuss recent progress in the understanding of intracellular molecular mechanisms controlling GH and IGF-I action. We then emphasize current advances in genetic and epigenetic mechanisms that control gene expression, and which support a key role for epigenetic regulation in the cascade of intracellular events that trigger GH action when coupled to its receptor. Thirdly, we focus on fetal programming and epigenetic regulation at the IGF1 locus. We then discuss epigenetic alterations in intrauterine growth retardation, and the possibility for a potential epigenetic pharmaceutical approach in short stature associated with this fetal condition. Lastly, we review an example of epigenetic therapeutics in the context of growth-related epigenetic deregulation disorders. The advance of our understanding of epigenetic changes and the impact they are having on new forms of therapy creates exciting prospects for the future.
Assuntos
Epigênese Genética/genética , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Animais , Feminino , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/metabolismo , Hormônio do Crescimento/genética , Humanos , Fator de Crescimento Insulin-Like I/genética , GravidezRESUMO
AIM: The objective of this study was to determine the ability of biochemical analytes to identify adverse outcomes in pregnancies with Turner syndrome. METHODS: Maternal serum and amniotic fluid (AF) marker concentrations were measured in 73 singleton pregnancies with Turner syndrome (10-22 weeks of gestation). Fetal Turner syndrome was definitively established by cytogenetic analysis. Two subgroups, fetuses with hydrops fetalis versus fetuses with cystic hygroma, were compared. Receiver operating characteristic curves and relative risk were established for a cut-off multiples of the median ≥3.5 for ß-subunit of human chorionic gonadotropin (hCG) or AF alpha-fetoprotein (AFP). RESULTS: Forty-nine (67%) of 73 pregnant women had an abnormal maternal serum. While levels of pregnancy-associated plasma protein-A and free ß-subunit (fß)-hCG were not different to those of the control group, AFP, unconjugated estriol and ß-hCG concentrations were significantly different in the study group (P < 0.05), when compared to those of unaffected pregnancies. Levels of ß-hCG in pregnancies with hydrops fetalis were significantly higher than in those with cystic hygroma (P <0.0001), as were AF-AFP concentrations (P <0.0015). In addition, abnormalities in both maternal serum ß-hCG and AF-AFP predicted fetal death. The relative risk of adverse obstetric outcome was 10.667 (P = 0.0004; 95% confidence interval [CI]: 1.554-73.203) for ß-hCG and 2.19 (P = 0.0256; 95% CI: 1.001 to 4.779), for AF-AFP. CONCLUSION: Maternal serum ß-hCG and AF-AFP levels may preferentially identify those Turner syndrome pregnancies with the highest risk of fetal death.
Assuntos
Líquido Amniótico/química , Gonadotropina Coriônica Humana Subunidade beta/sangue , Doenças Fetais , Síndrome de Turner/complicações , alfa-Fetoproteínas/análise , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez , Curva ROCRESUMO
OBJECTIVES: 1. To determine BMI, obesity/overweight rates, glucose and lipids at baseline, during GnRHa treatment and shortly after therapy discontinuation in female children with CPP and EP. 2. To compare this response to that seen in a similar group of untreated patients. METHODS: A retrospective analysis of 71 children with either CPP (n = 37) or EP (n = 34) was undertaken. Forty three were treated with a GnRHa for at least 2 years, while 28 were followed without treatment. RESULTS: At the time of diagnosis, a higher BMI (z-score of 1.1 ± 0.8 vs. 0.6 ± 0.7, p = 0.004) and a higher prevalence of obesity/overweight (72.9 vs. 35.3%, p = 0.001) was observed in subjects with CPP when compared to those with EP. Children with EP had higher fasting glucose and total cholesterol than those with CPP. BMI z-score, obesity/overweight rates, fasting glucose and lipids did not change significantly in girls with CPP or EP during 3 yrs of follow up, regardless of treatment. Weight z-scores were higher at 3 years in treated than in untreated girls with CPP (p = 0.02), while it was higher in untreated than in GnRHa-treated patients with EP at baseline, 1, 2 and 3 years (p = 0.007, p = 0.002, p = 0.02 and p = 0.04, respectively) and remained so shortly after stopping therapy (p = 0.03). CONCLUSIONS: There is a high prevalence of obesity/overweight in girls with CPP and EP at diagnosis. However, this risk is greater in CPP than in EP girls. BMI, Obesity/overweight rates, fasting glucose and lipids remained stable in CPP and EP girls regardless of therapy. Weight z-scores were found to be higher in treated CPP girls and in untreated girls with EP.
RESUMO
BACKGROUND: It is possible that genes on the X chromosome are expressed differently depending of its parental origin. The objective of this study was to determine the influence of the parental origin of the X-chromosome on phenotypic variability, response to rhGH and on the biochemical profile of TS patients. METHODS: This was a cross-sectional multicenter correlational study carried out over three years in six Latin-American university hospitals. Unrelated 45,X TS patients (n = 93; 18.3 ± 8.5 years )) were evaluated. A subgroup (n = 34) of the patients were prospectively treated with rhGH over two years. DNA profiles of patients and their mothers were compared to determine the parental origin of the retained X-chromosome through 10 polymorphic X-chromosome-STRs. The association with clinical features, biochemical profiles and anthropometric data at the beginning and after two years of rhGH treatment was determined. RESULTS: Seventy two percent of patients retained the maternal X chromosome (Xm). A trend towards significance between maternal height and patients final height (p ≤ 0.07) in 45,Xm subjects was observed. There was no correlation between paternal height and patient height. No differences were detected between both groups in regard to dysmorphic features, classical malformations or increase in the height-SDS after rhGH. There were higher levels of triglycerides, total and LDL cholesterol in patients >20 years who retained the Xm. CONCLUSIONS: The parental origin of the retained X chromosome may influence lipid metabolism in TS patients, but its effect on growth seems to be minimal. No parental-origin-effect on the phenotypic features, associated anomalies and on the growth response to rhGH was found in 45,X TS individuals.
RESUMO
BACKGROUND: Children born small for gestational age (SGA) experience higher rates of morbidity and mortality than those born appropriate for gestational age. In Latin America, identification and optimal management of children born SGA is a critical issue. Leading experts in pediatric endocrinology throughout Latin America established working groups in order to discuss key challenges regarding the evaluation and management of children born SGA and ultimately develop a consensus statement. DISCUSSION: SGA is defined as a birth weight and/or birth length greater than 2 standard deviations (SD) below the population reference mean for gestational age. SGA refers to body size and implies length-weight reference data in a geographical population whose ethnicity is known and specific to this group. Ideally, each country/region within Latin America should establish its own standards and make relevant updates. SGA children should be evaluated with standardized measures by trained personnel every 3 months during year 1 and every 6 months during year 2. Those without catch-up growth within the first 6 months of life need further evaluation, as do children whose weight is ≤ -2 SD at age 2 years. Growth hormone treatment can begin in SGA children > 2 years with short stature (< -2.0 SD) and a growth velocity < 25th percentile for their age, and should continue until final height (a growth velocity below 2 cm/year or a bone age of > 14 years for girls and > 16 years for boys) is reached. Blood glucose, thyroid function, HbA1c, and insulin-like growth factor-1 (IGF-1) should be monitored once a year. Monitoring insulin changes from baseline and surrogates of insulin sensitivity is essential. Reduced fetal growth followed by excessive postnatal catch-up in height, and particularly in weight, should be closely monitored. In both sexes, gonadal function should be monitored especially during puberty. SUMMARY: Children born SGA should be carefully followed by a multidisciplinary group that includes perinatologists, pediatricians, nutritionists, and pediatric endocrinologists since 10% to 15% will continue to have weight and height deficiency through development and may benefit from growth hormone treatment. Standards/guidelines should be developed on a country/region basis throughout Latin America.
Assuntos
Transtornos do Crescimento/tratamento farmacológico , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Pré-Escolar , Diabetes Mellitus Tipo 2/etiologia , Relação Dose-Resposta a Droga , Dislipidemias/etiologia , Feminino , Transtornos do Crescimento/complicações , Transtornos do Crescimento/etiologia , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Hiperandrogenismo/etiologia , Hipertensão/etiologia , Hipoglicemiantes/uso terapêutico , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Resistência à Insulina , América Latina/epidemiologia , Masculino , Metformina/uso terapêutico , Puberdade , Valores de Referência , Fatores de RiscoRESUMO
Objectives. To investigate whether lifestyle-only intervention in obese children who maintain or lose a modest amount of weight redistributes parameters of body composition and reverses metabolic abnormalities. Study Design. Clinical, anthropometric, and metabolic parameters were assessed in 111 overweight or obese children (CA of 11.3 ± 2.8 years; 63 females and 48 males), during 8 months of lifestyle intervention. Patients maintained or lost weight (1-5%) (group A; n: 72) or gained weight (group B). Results. Group A patients presented with a decrease in systolic blood pressure (SBP) and diastolic blood pressure (DBP) (P < .005 and P < .05, resp.), BMI (P < .0001), z-score BMI (P < .0001), waist circumference (P < .0001), fat mass (P < .005), LDL-C (P < .05), Tg/HDL-C ratio (P < .05), fasting and postprandial insulin (P < .005), and HOMA (P < .005), while HDL-C (P < .05) and QUICKI increased (P < .005). Conversely, group B patients had an increase in BMI (P < .0001), waist circumference (P < .005), SBP (P < .005), and in QUICKI (P < .005), while fat mass (P < .05), fasting insulin (P < .05), and HOMA (P < .05) decreased. Lean mass, DBP, lipid concentrations, fasting and postprandial glucose, postprandial insulin, and ultrasensitive C-reactive protein (CRP) remained stable. Conclusions. Obese children who maintain or lose a modest amount of weight following lifestyle-only intervention tend to redistribute their body fat, decrease blood pressure and lipid levels, and to improve parameters of insulin sensitivity.
Assuntos
Técnicas de Diagnóstico Endócrino , Hormônios Esteroides Gonadais/administração & dosagem , Transtornos do Crescimento/diagnóstico , Criança , Diagnóstico Diferencial , Esquema de Medicação , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Estradiol/farmacologia , Estrogênios Conjugados (USP)/administração & dosagem , Estrogênios Conjugados (USP)/farmacologia , Hormônios Esteroides Gonadais/farmacologia , Transtornos do Crescimento/tratamento farmacológico , Transtornos do Crescimento/metabolismo , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/deficiência , Hormônio do Crescimento Humano/metabolismo , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Hipopituitarismo/diagnóstico , Hipopituitarismo/metabolismo , Masculino , Valor Preditivo dos Testes , Prognóstico , Via Secretória/efeitos dos fármacosRESUMO
We have prospectively assessed the influence of GHR and VDR gene polymorphisms on the response to rhGH therapy in Venezuelan children with growth hormone deficiency (GHD, n=28) and Turner syndrome (TS, n=25). Clinical data during rhGH treatment were compared in GH and TS patients with different genotypes. PCR amplifications were performed to obtain the genotype frequencies of the polymorphisms. Clinical data at the start of treatment and rhGH doses were indistinguishable among patients with GHD or TS with different GHR or VDR genotypes. After the first two years of rhGH treatment, clinical data in both GHD and TS patients were not different according GHR or VDR genotypes. In addition, there was no significant difference among the subjects when both these genotypes were combined. Gene polymorphisms in low penetrance genes do not contribute to the rhGH therapy response in patients with GHD and TS.
Assuntos
Proteínas de Transporte/genética , Nanismo Hipofisário/genética , Hormônio do Crescimento Humano/uso terapêutico , Polimorfismo Genético , Receptores de Calcitriol/genética , Síndrome de Turner/genética , Criança , Pré-Escolar , Análise Mutacional de DNA , Nanismo Hipofisário/tratamento farmacológico , Feminino , Genótipo , Humanos , Masculino , Estudos Prospectivos , Proteínas Recombinantes , Resultado do Tratamento , Síndrome de Turner/tratamento farmacológicoAssuntos
Hormônio do Crescimento/uso terapêutico , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/deficiência , Puberdade , Adolescente , Fatores Etários , Idade de Início , Densidade Óssea/efeitos dos fármacos , Doenças Cardiovasculares/complicações , Doenças Cardiovasculares/prevenção & controle , Criança , Monitoramento de Medicamentos , Nanismo Hipofisário/diagnóstico , Nanismo Hipofisário/tratamento farmacológico , Nanismo Hipofisário/genética , Nanismo Hipofisário/metabolismo , Hormônio do Crescimento/farmacologia , Hormônio do Crescimento Humano/genética , Hormônio do Crescimento Humano/fisiologia , Humanos , América Latina , Desenvolvimento Muscular/efeitos dos fármacos , Adulto JovemRESUMO
Objetivos. La deleción (GHRd3) o inserción (GHRfl) del exón 3 es un polimorfismo común en el gen del receptor de la hormona de crecimiento (GHR) en los seres humanos. La presencia del alelo GHRd3 se ha asociado con el grado de respuesta de terapia con Hormona de Crecimiento Recombinante Humana (rhGH). El objetivo de este estudio fue determinar las frecuencias alélicas y genotípicas de este polimorfismo en un grupo de 69 niños venezolanos con talla baja que estaban recibiendo rhGH. Métodos. Se extrajo DNA a través de la técnica del método combinado Fenol/Sevag e Inorgánica. Se determinó el genotipo del exón 3 del gen GHR usando tanto PCR- monoplex como PCR-multiplex. Resultados. Entre los pacientes con talla baja la frecuencia genotípica se distribuyó de la siguiente manera: GHRfl/GHRfl (55%) GHRfl/GHRd3 (35%) y GHRd3/GHRd3 (10%) y la frecuencia alélica fue de 0,27 para GHRd3 y 0,73 para GHRfl. Para el grupo testigo la frecuencia genotípica se distribuyo así: GHRfl/GHRfl (56%), GHRfl/ GHRd3 (30%) y GHRd3/GHRd3 (14%) y la frecuencia alélica era de 0,29 para GHRd3 y 0,71 para GHRfl. Las características clínicas basales de los pacientes con talla baja eran similares entre los diferentes genotipos encontrados en el grupo de estudio. Conclusiones. La proporción del genotipo y los alelos del gen GHR fueron similares entre el grupo testigo y los pacientes con talla baja, lo que traduce que la etiología de la talla baja no obedece a este polimorfismo.
Objective. The deletion (GHRd3) or insertion (GHRfl) of exon 3 is a common polymorphism in the receptor growth hormone gene (GHR) in humans. The presence of the allele GHRd3 has been associated with the degree of responsiveness to therapy with recombinant human Growth Hormone (rhGH). The aim of this study was to determine the genotypic and allele frequencies of this polymorphism in a group of 69 Venezuelan children with short stature who were receiving rhGH. Methods. Genomic DNA was extracted from blood lymphocytes using combined method Fenol/SEVAG + Salting out. The GHR-exon 3 was genotyped using both PCR monoplex and multiplex assays. Results. Among patients with short stature, genotype frequency was distributed as follows: GHRfl/GHRfl (55%), GHRfl/GHRd3 (35%) and GHRd3/GHRd3 (10%) and allele frequency for GHRd3 and GHRfl was 0.27 and 0.73, respectively. For the control group, genotype frequency was distributed as follows: GHRfl/GHRfl (56%), GHRfl/GHRd3 (30%) and GHRd3/GHRd3 (14%) and allele frequency for GHRd3 and GHRfl was 0.29 and 0.71, respectively. The baseline clinical features of patients with short stature were similar among different genotypes found in the study group. Conclusions. The proportion of genotype and allele of the GHR gene were similar between the control group and patients with short stature, which translates that the etiology of short stature is not due to this polymorphism.
RESUMO
Increased cardiovascular morbidity and mortality has been reported in adult subjects with growth hormone deficiency (GHD). Long term follow up of a large cohort of patients with adult onset GHD, suggests that GH therapy may contribute to a reduced risk of nonfatal stroke, particularly in women and in a decline in nonfatal cardiac events in GHD men(1,2). Adult hypopituitary patients with untreated growth hormone deficiency have been shown to have a cluster of cardiovascular risk factors such as increased visceral adiposity, disturbances in lipoprotein metabolism, premature atherosclerosis, impaired fibrinolytic activity, increased peripheral insulin resistance, abnormal cardiac structure, impaired cardiac performance and endothelial dysfunction (3,4). Several of these risk factors have now been confirmed in double blind, randomized, placebo controlled trials (5,6). Metabolic changes in GH deficient children and adolescents have been evaluated only quite recently and superficially. In this article we will discuss these metabolic abnormalities and their underlying mechanism in untreated GHD subjects and we will review the beneficial effect of growth hormone therapy in adults, adolescents and children with GHD.
Se ha reportado un aumento en la morbilidad y mortalidad de pacientes adultos con deficiencia de la hormona de crecimiento (DHC). El seguimiento a largo plazo de una cohorte de pacientes con DHC sugiere que la administracion de hormona de crecimiento puede contribuir a una reducción en el número de los accidentes cerebrovasculares no fatales, particularmente en mujeres y de eventos cardíacos en hombres(1,2). Pacientes adultos con hipopituitarismo y una DHC cursan con un acúmulo de factores de riesgo cardiovascular tales como un aumento en la adiposidad visceral, alteraciones en el metabolismo lipoproteico, ateroesclerosis prematura, actividad fibrinolítica alterada, resistencia a la insulina, masa y función cardíaca alterada y disfunción endotelial (3,4). Varios de estos factores de riesgo han sido comprobados en estudios doble ciego, randomizados con placebo (5,6). Las alteraciones metabólicas en niños y adolescentes deficientes de hormona de crecimiento han sido evaluadas sólo recientemente y de manera aún superficial. En este manuscrito discutiremos estas anormalidades y los mecanismos etilógicos subyacentes en sujetos DHC no tratados y revisaremos el efecto beneficioso de la terapia con hormona de crecimiento en niños, adolescentes y adultos.
Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Adulto , Hormônio do Crescimento Humano/deficiência , Resistência à Insulina/fisiologia , Fatores de Risco , Morbidade , Mortalidade , Hormônio do Crescimento Humano/administração & dosagem , Hormônio do Crescimento Humano/uso terapêutico , Acidente Vascular Cerebral/prevenção & controle , Adiposidade , Hipopituitarismo/complicações , Lipoproteínas/químicaRESUMO
BACKGROUND/AIMS: Significant endothelial dysfunction as determined by lower flow-mediated vasodilation of the brachial artery was recently reported by us in growth hormone-deficient (GHD) adolescents. The circulating concentrations of markers of vascular endothelial cell and platelet activation and their relationship to inflammatory markers have not been previously evaluated in this group of patients. OBJECTIVE: To assess the relationship between circulating levels of high-sensitivity C-reactive protein (CRP) and soluble markers of vascular endothelial cell activation in GHD adolescents. DESIGN/METHODS: Twenty-eight GHD children on GH treatment with a chronological age of 15.7 +/- 2.6 years and 16 untreated GHD adolescents with a chronological age of 16.6 +/- 3.3 years were studied. Concentrations of CRP, as an inflammatory marker, were measured in all patients and the association between CRP and the fasting soluble markers of vascular endothelial cell activation intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin and P-selectin levels was evaluated. Sixteen healthy adolescents with a mean chronological age of 15.1 +/- 2.2 years served as controls. RESULTS: CRP and P-selectin levels were significantly higher in untreated GHD adolescents than in treated GHD subjects or in healthy controls (p < 0.02), while VCAM-1 concentrations were increased in both untreated and treated GHD adolescents when compared to controls (p < 0.007). E-selectin and ICAM-1 levels were similar in all three groups. CRP was found to be associated with BMI (r: 0.62; p < 0.001), P-selectin (r: 0.43; p < 0.01), E-selectin (r: 0.27; p < 0.03), ICAM-1 (r: 0.23; p < 0.05) and VCAM-1 (r: 0.40; p < 0.001) concentrations in untreated GHD adolescents and with P-selectin (r: 0.88; p < 0.001) and E-selectin (r: 0.29; p < 0.01) in treated GHD subjects. A weak inverse association was observed in a subgroup of patients between brachial artery endothelium-dependent dilation and P-selectin (r: -0.56; p < 0.07). CONCLUSIONS: Low-grade inflammation as manifested by increased circulating levels of CRP seems to be associated with the early activation of vascular endothelial cells in GHD adolescents.