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1.
Reprod Biol Endocrinol ; 15(1): 56, 2017 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-28738839

RESUMEN

BACKGROUND: We and others have observed that young girls predisposed to polycystic ovary syndrome (PCOS) display defective insulin sensitivity, beta-cell function and non-esterified fatty acids (NEFA) suppressibility during early pubertal years, compared to controls. Our objective is to assess whether these differences in glucose and NEFA metabolisms persist after 5 years in late/post-puberty. METHODS: We conducted a prospective cohort study between 2007 and 2015 with 4-6 years of follow-up in an academic institution research center. We compared 8 daughters and sisters of PCOS women (PCOSr) to 8 age-matched girls unrelated to PCOS (±1.5 years). Girls were assessed initially at 8-14 years old and re-assessed after a median follow-up of 5.4 years, at 13-21 years old. Our main measures were a frequently sampled intravenous glucose tolerance test (FSivGTT)-derived insulin sensitivity (IS) and beta-cell function (disposition index, DIFSivGTT); and indices of NEFA suppression during FSivGTT (logn-linear slope of NEFA and T50 of NEFA suppression). RESULTS: At follow-up, both PCOSr and controls had similar results: IS = 3.2 vs 3.4 (p = 0.88), DIFSivGTT = 1926 vs 1380 (p = 0.44), logn-linear slope = -0.032 vs -0.032 (p = 0.88) and T50NEFA = 18.1 vs 20.8 min (p = 0.57). IS, DIFSivGTT and NEFA suppressibility were stable in PCOSr after 5 years, but decreased significantly in controls (all p < 0.05). CONCLUSIONS: Impaired metabolism observed during early puberty in girls predisposed to PCOS remains stable after 5 years whereas control girls deteriorated their metabolic parameters. Therefore, both groups become comparable in late/post-puberty. Early puberty may thus represent a window during which metabolic alterations are transiently apparent in girls at risk of PCOS.


Asunto(s)
Resistencia a la Insulina , Síndrome del Ovario Poliquístico/metabolismo , Pubertad Precoz/metabolismo , Adolescente , Ácidos Grasos no Esterificados/metabolismo , Femenino , Estudios de Seguimiento , Glucosa/metabolismo , Homeostasis , Humanos , Adulto Joven
2.
Diabetologia ; 59(11): 2378-2386, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27567623

RESUMEN

AIMS/HYPOTHESIS: Endothelial cells (ECs) play an essential role in pancreatic organogenesis. We hypothesise that effective in vitro interactions between human microvascular endothelial cells (HMECs) and human pluripotent stem cells (hPSCs) results in the generation of functional pancreatic beta cells. METHODS: Embryoid bodies (EBs) derived from hPSCs were cultured alone (controls) or with ECs in collagen gels. Subsequently, cells were analysed for pancreatic beta cell markers, and then isolated and expanded. Insulin secretion in response to glucose was evaluated in vitro by static and dynamic (perifusion) assays, and in vivo by EB transplantation into immunodeficient mice. RESULTS: Co-cultured EBs had a higher expression of mature beta cells markers and enhanced insulin secretion in vitro, compared with controls. In mice, transplanted EBs had higher levels of human C-peptide secretion with a significant reduction in hyperglycaemia after the selective destruction of native pancreatic beta cells. In addition, there was significant in vitro upregulation of bone morphogenetic proteins 2 and 4 (BMP-2, 4) in co-cultured cells, compared with controls. CONCLUSIONS/INTERPRETATION: ECs provide essential signalling in vitro, such as activation of the BMP pathway, for derivation of functional insulin-producing beta cells from hPSCs.


Asunto(s)
Células Secretoras de Insulina/citología , Células Secretoras de Insulina/metabolismo , Insulina/sangre , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Animales , Proteína Morfogenética Ósea 2/metabolismo , Proteína Morfogenética Ósea 4/metabolismo , Línea Celular , Cuerpos Embrioides/citología , Cuerpos Embrioides/metabolismo , Humanos , Hiperglucemia/metabolismo , Inmunohistoquímica , Ratones
3.
Adolesc Health Med Ther ; 14: 125-140, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37641650

RESUMEN

The prevalence of pediatric obesity has increased exponentially over the past four decades. The American Academy of Pediatrics recently released updated clinical practice guidelines highlighting the importance of identifying pediatric obesity as a chronic disease. The guidelines support consideration of concurrent treatment with intensive lifestyle interventions, obesity pharmacotherapy, and bariatric surgery. The dramatic rise in pediatric obesity has spurred interest in utilizing obesity pharmacotherapy to support sustained weight reduction in pediatric cohorts, in the hopes of preventing the emergence of later-appearing, significant co-morbidities. Despite the enormous demand, the obstacles posed by performance of needed clinical trials in the pediatric population markedly limits available pharmacotherapy for the treatment of obesity in pediatrics. Currently, there are five medications approved by the Food and Drug Administration for use in youth with obesity. In 2022, the phentermine/topiramate (PHEN/TPM), once-daily, controlled-release, combination product received FDA approval, for the indication of chronic weight management, in youth with obesity, ages 12 years and older. The objectives of this narrative review are to: (1) Review the mechanism of action of phentermine and topiramate, (2) Summarize the safety and efficacy data of topiramate and phentermine use as both monotherapies and in combination, and (3) Discuss clinical practice guidelines and clinical implications, for the use of these agents in youths with obesity.

4.
J Clin Endocrinol Metab ; 107(3): e912-e923, 2022 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-34752621

RESUMEN

CONTEXT: First-degree relatives of women with polycystic ovary syndrome (PCOS) present hormonal and metabolic alterations compared to girls unrelated to PCOS. It is unknown whether glucose intolerance in the PCOS proband confers a more severe metabolic predisposition on their first-degree relatives. OBJECTIVE: To determine whether glucose tolerance status in women with PCOS is associated with worsened glucose metabolism and sex hormone levels in their peripubertal daughters or sisters. DESIGN: Cross-sectional study. SETTING: Seven academic centers in North America, South America, and Europe. PATIENTS: Sixty-four pairs of women with PCOS and their daughters or younger sisters aged between 8 and 14 years were recruited. Twenty-five mothers or older sisters with PCOS were glucose intolerant (GI) and 39 were normal glucose tolerant (NGT). MAIN OUTCOME MEASURES: Beta-cell function estimated by the insulin secretion-sensitivity index-2 (ISSI-2) during an oral glucose tolerance test and by the disposition index during a frequently sampled IV glucose tolerance test. Free testosterone and 17-hydroxyprogesterone (17-OHP) levels. RESULTS: Being related to a GI PCOS proband was associated with a lower ISSI-2 (P-value = 0.032) after adjusting for ethnicity, body mass index z-score, and pubertal stage. They also had higher free testosterone (P-value = 0.011) and 17-OHP levels compared to girls with an NGT proband, the latter becoming significant after adjusting for confounders (P-value = 0.040). CONCLUSIONS: Compared to first-degree female relatives of women with PCOS and NGT, first-degree relatives of women with PCOS and GI display lower beta-cell function and hyperandrogenemia, putting them at higher risk of GI and PCOS development.


Asunto(s)
Andrógenos/sangre , Intolerancia a la Glucosa/epidemiología , Ovario/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , Adolescente , Andrógenos/metabolismo , Niño , Estudios Transversales , Femenino , Glucosa/metabolismo , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/diagnóstico , Intolerancia a la Glucosa/metabolismo , Prueba de Tolerancia a la Glucosa , Humanos , Insulina/metabolismo , Resistencia a la Insulina , Células Secretoras de Insulina/metabolismo , Núcleo Familiar , Ovario/patología , Factores de Riesgo , Hermanos
7.
J Clin Transl Endocrinol ; 2(3): 99-104, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26236647

RESUMEN

OBJECTIVE: Insulin resistance is a common feature of polycystic ovary syndrome (PCOS). The insulin signaling pathway consists of two major pathways, the metabolic and the mitogenic cascades. The many components of these pathways have not been comprehensively analyzed for differential expression in insulin-responsive tissues in PCOS. The goal of this study was to determine whether the core elements of the insulin signal transduction cascade were differentially expressed in subcutaneous adipose tissue (SAT) between PCOS and controls. MATERIALS/METHODS: Quantitative real-time PCR for 36 insulin signaling pathway genes was performed subcutaneous adipose tissue from 22 white PCOS and 13 healthy controls. RESULTS: Genes in the insulin signaling pathway were not differentially expressed in subcutaneous adipose tissue between PCOS and controls (P>0.05 for all). Components mainly of the mitogenic pathway were correlated with both androgens and metabolic phenotypes. Expression levels of five genes (MKNK1, HRAS, NRAS, KRAS, and GSK3A) were positively correlated with total testosterone level (ρ>0, P<0.05). Inverse correlation was found between expression of six genes (HRAS, MAP2K2, NRAS, MAPK3, GRB2, and SHC1) and metabolic traits (body mass index, fasting glucose, fasting insulin, and HOMA-IR) (ρ<0, P<0.05). CONCLUSIONS: Differential expression of core insulin signaling pathway components in subcutaneous adipose tissue is not a major contributor to the pathogenesis of PCOS. Correlation between clinical phenotypes and expression of several genes in the mitogenic limb of the insulin signaling pathway suggests mitogenic signaling by insulin may regulate steroidogenesis and glucose homeostasis.

8.
Endocrinology ; 145(1): 175-83, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14512432

RESUMEN

Polycystic ovary syndrome, characterized by hyperandrogenism and chronic anovulation, is frequently associated with insulin resistance. Ample evidence implicates a role for insulin in the genesis of ovarian hyperandrogenism. The objective of this study was to begin to define the intracellular signaling pathway(s) that mediates insulin regulation of 17alpha-hydroxylase activity in human ovarian theca cells. Third-passage theca cells, isolated from the ovaries of regularly cycling premenopausal women, were used. Insulin alone had no effect on 17alpha-hydroxylase activity or CYP17 mRNA expression but required costimulation with forskolin. At the insulin concentration used (10 ng/ml), a neutralizing antibody to the insulin receptor (but not an antibody to the type I IGF receptor) blocked the insulin stimulation of 17alpha-hydroxylase activity, demonstrating that the effects were mediated by the insulin receptor. Insulin stimulated both phosphatidylinositol-3-kinase (PI3-kinase) and extracellular signal-regulated kinase-1/2 (MAPK) pathways. Specific inhibition of MAPK kinase (MEK) with PD98059 or I0126 did not decrease the 17alpha-hydroxylase activity stimulated by forskolin or forskolin plus insulin. In contrast, the PI3-kinase inhibitor LY294002 completely blocked insulin-stimulated 17alpha-hydroxylase activity. Our data demonstrate that insulin stimulates PI3-kinase and extracellular signal-regulated kinase-1/2 activities in human theca cells, but only PI3-kinase mediates the insulin augmentation of forskolin-stimulated 17alpha-hydroxylase activity.


Asunto(s)
Hipoglucemiantes/farmacología , Insulina/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Esteroide 17-alfa-Hidroxilasa/metabolismo , Células Tecales/enzimología , Andrógenos/biosíntesis , Células Cultivadas , Colforsina/farmacología , Inhibidores Enzimáticos/farmacología , Femenino , Flavonoides/farmacología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/fisiología , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Síndrome del Ovario Poliquístico/metabolismo , ARN Mensajero/análisis , Esteroide 17-alfa-Hidroxilasa/genética , Células Tecales/citología , Células Tecales/efectos de los fármacos
9.
Fertil Steril ; 98(6): 1627-34, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22985947

RESUMEN

OBJECTIVE: To assess metabolic and endocrine defects in girls genetically predisposed to polycystic ovary syndrome (PCOS). DESIGN: Controlled cross-sectional study. SETTING: University hospital. PATIENT(S): Nine girls, aged 8-14 years, having a first-degree relative diagnosed with PCOS (PCOSr) and 10 age-matched girls without a family history of PCOS. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Insulin sensitivity (IS(FSIVGTT)) determined by frequently sampled IV glucose tolerance testing (GTT) and insulin-induced nonesterified fatty acid (NEFA) suppression, estimated by the log-linear slope of NEFA levels during the first 20 minutes of GTT. RESULT(S): In comparison to controls, PCOSr had higher body mass index (BMI) Z-score, waist circumference, and waist-to-height ratio. Levels of the androgen 17α-hydroxyprogesterone (17-OHP) were significantly increased in PCOSr, independent of adiposity, and inversely correlated with IS(FSIVGTT). The IS(FSIVGTT) was decreased and the NEFA suppression was less steep in PCOSr compared with controls, independent of BMI and 17-OHP. The NEFA suppression was more pronounced with increasing IS(FSIVGTT), independent of adiposity. CONCLUSION(S): Girls at high risk of developing PCOS display increased adiposity and 17-OHP levels, but are mainly characterized by global insulin resistance and resistance to insulin-induced suppression of lipolysis that were independent of adiposity and 17-OHP levels. Therefore, genetic predisposition to PCOS may be related to early insulin resistance and adipocyte dysfunction.


Asunto(s)
Tejido Adiposo/fisiopatología , Resistencia a la Insulina , Síndrome Metabólico/fisiopatología , Síndrome del Ovario Poliquístico/fisiopatología , Pubertad , Adolescente , Niño , Femenino , Humanos
10.
Int J Pediatr Endocrinol ; 2011: 9, 2011 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-21899727

RESUMEN

PCOS, a heterogeneous disorder characterized by cystic ovarian morphology, androgen excess, and/or irregular periods, emerges during or shortly after puberty. Peri- and post-pubertal obesity, insulin resistance and consequent hyperinsulinemia are highly prevalent co-morbidities of PCOS and promote an ongoing state of excess androgen. Given the relationship of insulin to androgen excess, reduction of insulin secretion and/or improvement of its action at target tissues offer the possibility of improving the physical stigmata of androgen excess by correction of the reproductive dysfunction and preventing metabolic derangements from becoming entrenched. While lifestyle changes that concentrate on behavioral, dietary and exercise regimens should be considered as first line therapy for weight reduction and normalization of insulin levels in adolescents with PCOS, several therapeutic options are available and in wide use, including oral contraceptives, metformin, thiazolidenediones and spironolactone. Overwhelmingly, the data on the safety and efficacy of these medications derive from the adult PCOS literature. Despite the paucity of randomized control trials to adequately evaluate these modalities in adolescents, their use, particularly that of metformin, has gained popularity in the pediatric endocrine community. In this article, we present an overview of the use of insulin sensitizing medications in PCOS and review both the adult and (where available) adolescent literature, focusing specifically on the use of metformin in both mono- and combination therapy.

11.
PLoS One ; 6(11): e27286, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22076147

RESUMEN

The pathogenesis of polycystic ovary syndrome (PCOS) is poorly understood. PCOS-like phenotypes are produced by prenatal androgenization (PA) of female rhesus monkeys. We hypothesize that perturbation of the epigenome, through altered DNA methylation, is one of the mechanisms whereby PA reprograms monkeys to develop PCOS. Infant and adult visceral adipose tissues (VAT) harvested from 15 PA and 10 control monkeys were studied. Bisulfite treated samples were subjected to genome-wide CpG methylation analysis, designed to simultaneously measure methylation levels at 27,578 CpG sites. Analysis was carried out using Bayesian Classification with Singular Value Decomposition (BCSVD), testing all probes simultaneously in a single test. Stringent criteria were then applied to filter out invalid probes due to sequence dissimilarities between human probes and monkey DNA, and then mapped to the rhesus genome. This yielded differentially methylated loci between PA and control monkeys, 163 in infant VAT, and 325 in adult VAT (BCSVD P<0.05). Among these two sets of genes, we identified several significant pathways, including the antiproliferative role of TOB in T cell signaling and transforming growth factor-ß (TGF-ß) signaling. Our results suggest PA may modify DNA methylation patterns in both infant and adult VAT. This pilot study suggests that excess fetal androgen exposure in female nonhuman primates may predispose to PCOS via alteration of the epigenome, providing a novel avenue to understand PCOS in humans.


Asunto(s)
Andrógenos/metabolismo , Epigénesis Genética , Síndrome del Ovario Poliquístico/etiología , Complicaciones Neoplásicas del Embarazo/etiología , Animales , Animales Recién Nacidos , Teorema de Bayes , Metilación de ADN , Femenino , Grasa Intraabdominal/patología , Macaca mulatta , Proyectos Piloto , Síndrome del Ovario Poliquístico/metabolismo , Síndrome del Ovario Poliquístico/patología , Embarazo , Complicaciones Neoplásicas del Embarazo/metabolismo , Complicaciones Neoplásicas del Embarazo/patología , Efectos Tardíos de la Exposición Prenatal , Transducción de Señal , Factor de Crecimiento Transformador beta/metabolismo , Virilismo
12.
Fertil Steril ; 85 Suppl 1: 1290-9, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16616104

RESUMEN

OBJECTIVE: To investigate the role of serine-threonine phosphorylation on the activity of human P450c17. DESIGN: In vitro study. SETTING: Academic basic research laboratory. PATIENT(S): None. INTERVENTION(S): P450c17 expression constructs with a FLAG-tag on either the C-terminus or N-terminus of the protein were generated. Human C-terminal FLAG-tagged P450c17 chromosomal DNA was subjected to site-directed mutagenesis. Serine 258 and threonine 260 each were mutated to alanine and aspartic acid. The mutant P450c17s were expressed in COS-7 cells, and the enzymatic activities were measured. MAIN OUTCOME MEASURE(S): 17alpha-Hydroxylase and C(17-20) lyase activities of human P450c17. RESULT(S): C-terminal FLAG-tagged P450c17 functioned indistinguishably from the wild-type P450c17. Mutants S258A, S258D, and T260D had significantly less 17alpha-hydroxylase and C(17-20) lyase activities than the wild type. CONCLUSION(S): Adding an epitope tag to the C-terminus of the P450c17 protein does not interfere with its activities and will be a useful tool to isolate human P450c17 protein from cultured cells. Phosphorylation of serine 258 but not threonine 260 may act as a physiologic regulator of both enzymatic activities through interaction with obligatory redox partners.


Asunto(s)
Aminoácidos/química , Aminoácidos/metabolismo , Modelos Químicos , Modelos Moleculares , Esteroide 17-alfa-Hidroxilasa/química , Esteroide 17-alfa-Hidroxilasa/metabolismo , Aminoácidos/genética , Animales , Sitios de Unión , Células COS , Chlorocebus aethiops , Simulación por Computador , Activación Enzimática , Humanos , Mutagénesis Sitio-Dirigida , Unión Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Esteroide 17-alfa-Hidroxilasa/genética
13.
J Pediatr ; 148(1): 128-31, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16423613

RESUMEN

We report the successful use of oral urea in the management of children with chronic syndrome of inappropriate antidiuretic hormone secretion (SIAD). We performed a retrospective review of four children with chronic SIAD. After initial attempts at management with fluid restriction, each was started on a 30% to 50% oral urea solution, and the dose was titrated until normal serum sodium was achieved. Fluid intake was liberalized after serum sodium normalization. All four children normalized their serum sodium. No side effects or toxicities were experienced. Oral urea is a safe, effective treatment for chronic SIAD in children.


Asunto(s)
Síndrome de Secreción Inadecuada de ADH/tratamiento farmacológico , Urea/uso terapéutico , Administración Oral , Enfermedad Crónica , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Hiponatremia/tratamiento farmacológico , Hiponatremia/etiología , Síndrome de Secreción Inadecuada de ADH/complicaciones , Lactante , Masculino , Estudios Retrospectivos , Síndrome , Resultado del Tratamiento , Urea/administración & dosificación
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