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1.
Artículo en Inglés | MEDLINE | ID: mdl-32554829

RESUMEN

SUMMARY: HAIR-AN syndrome, the coexistence of Hirsutism, Insulin Resistance (IR) and Acanthosis Nigricans, constitutes a rare nosologic entity. It is characterized from clinical and biochemical hyperandrogenism accompanied with severe insulin resistance, chronic anovulation and metabolic abnormalities. Literally, HAIR-AN represents an extreme case of polycystic ovary syndrome (PCOS). In everyday practice, the management of HAIR-AN constitutes a therapeutic challenge with the available pharmaceutical agents. Specifically, the degree of IR cannot be significantly ameliorated with metformin administration, whereas oral contraceptives chronic administration is associated with worsening of metabolic profile. Liraglutide and exenatide, in combination with metformin, have been introduced in the management of significantly obese women with PCOS with satisfactory results. Based on this notion, we prescribed liraglutide in five women with HAIR-AN. In all participants a significant improvement regarding the degree of IR, fat depositions, androgen levels and the pattern of menstrual cycle was observed, with minimal weight loss. Furthermore, one woman became pregnant during liraglutide treatment giving birth to a healthy child. Accordingly, we conclude that liraglutide constitutes an effective alternative in the management of women with HAIR-AN. LEARNING POINTS: HAIR-AN management is challenging and classic therapeutic regimens are ineffective. Literally HAIR-AN syndrome, the coexistence of Hirsutism, Insulin Resistance and Acanthosis Nigricans, represents an extreme case of polycystic ovary syndrome. In cases of HAIR-AN, liraglutide constitutes an effective and safe choice.

2.
Mol Endocrinol ; 13(8): 1249-66, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10446901

RESUMEN

A region located remotely upstream of the human pituitary GH (GH-N) gene and required for efficient GH-N gene expression in the pituitary of transgenic mice was cloned as a 1.6-kb Bg/II (1.6G) fragment. The 1.6G fragment in the forward or reverse orientation increased -496GH-N promoter activity significantly in pituitary GC and GH3 cells after gene transfer. The 1.6G fragment was also able to stimulate activity from a minimal thymidine kinase (TK) promoter which, unlike -496GH-N, lacked any Pit-1/GHF-1 element. Enhancer activity was localized by deletion analysis to a 203-bp region in the 3'-end of the 1.6G fragment and was characterized by the presence of a diffuse 136-bp nuclease-protected site, observed with pituitary (GC) but not nonpituitary (HeLa) cell nuclear protein. A major low-mobility complex was observed by electrophoretic mobility shift assay (EMSA) with GC cell nuclear protein, and the pattern was distinct from that seen with a HeLa cell extract. The nuclease-protected region contains three A/T-rich Pit-1/ GHF-1-like elements, and their disruption, in the context of the 203-bp region fused to the TK promoter, reduced enhancer activity significantly in pituitary cells in culture. A mutation in this region was also shown to decrease enhancer activity in transgenic mice and correlated with a decrease in the 203-bp enhancer region complex observed by EMSA. The participation of Pit-1/GHF-1 in this complex is indicated by competition studies with Pit-1/GHF-1 elements and antibodies, and direct binding of Pit-1/GHF-1 to the A/T-rich sequences was shown by EMSA using recombinant protein. These studies link the A/T-rich sequences to the distal enhancer activity associated with the GH locus control region in vitro and in vivo.


Asunto(s)
Proteínas de Unión al ADN/fisiología , Elementos de Facilitación Genéticos , Hormona de Crecimiento Humana/genética , Adenohipófisis/metabolismo , Factores de Transcripción/fisiología , Animales , Secuencia de Bases , Sitios de Unión , Línea Celular , Coriocarcinoma , Eliminación de Gen , Células HeLa , Humanos , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Fragmentos de Péptidos/genética , Ratas , Timidina Quinasa/genética , Factor de Transcripción Pit-1 , Células Tumorales Cultivadas
3.
Mol Cell Endocrinol ; 157(1-2): 131-42, 1999 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-10619404

RESUMEN

Diabetes is a common complication encountered during pregnancy. Earlier studies indicated that diabetic placentas bear morphological alterations consistent with modified placental differentiation, including alterations in the villous cellular content, structure, and total surface. Limited data associating the diabetic status with the expression of terminal placental differentiation markers are available. The human growth hormone/chorionic somatomammotropin (hGH/CS) family consists of five genes, one of which (GH-N) is expressed efficiently in pituitary while the other four (CS-A, B, L, and hGH-V) are expressed in placenta and represent ultimate placental differentiation markers. We developed and applied a sensitive RT-PCR method coupled with diagnostic restriction digestion to determine the relative levels of the hGH/CS family in normal pregnancies and examine whether their mRNA expression pattern is altered in pregnancies complicated by diabetes. We show that relative hCS-L content changes during placental development. Specifically, normal term placentas express higher relative levels of hCS-L, lower relative hGH-V levels and a 70-fold lower hGH-V/CS-L mRNA ratio compared to early placentas. Also, many term placentas from diabetic pregnancies express lower relative levels of hCS-L mRNA and a much higher hGH-V/CS-L mRNA ratio compared to normal term placenta, resembling more an early placenta pattern of expression. Thus, our study suggests that the expression of terminal placental differentiation markers, such as the hGH/CS genes, is altered in term placentas from these diabetics reflecting either impaired placental differentiation or post-differentiation impairment of normal placental function.


Asunto(s)
Diabetes Gestacional/genética , Hormona del Crecimiento/genética , Hormonas Placentarias/genética , Lactógeno Placentario/genética , Femenino , Variación Genética , Edad Gestacional , Humanos , Placenta/química , Embarazo , ARN/biosíntesis , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
4.
Eur J Contracept Reprod Health Care ; 2(4): 213-24, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9678076

RESUMEN

Polycystic ovary syndrome is a common endocrine disorder, presenting with menstrual irregularities, hirsutism, obesity, infertility and abnormal ovarian morphology. In addition, polycystic ovary syndrome is associated with a self-perpetuating imbalance involving the endocrine system and metabolic pathways, in which carbohydrates, lipids and growth factors are involved. Because of its chronicity, it is considered to be a substantial risk factor for atherogenesis and hormone-dependent neoplasia. The etiology and pathophysiology of the syndrome remain elusive. However, during the last decade, several clues have emerged from human and animal studies that may have significant repercussions in the treatment of polycystic ovary syndrome. Therapeutic maneuvers should be directed towards the dominant abnormalities present in individual patients with polycystic ovary syndrome. Gonadotropin releasing hormone (GnRH) agonists can directly affect the gonadotropin generator and secondary downstream derangements, whereas combined oral contraceptives (COCs) can modify hypothalamic as well as peripheral abnormalities. In view of the fact that GnRH agonistic analogs (GnRH-a) will induce hypoestrogenemia and its sequelae, the add-back strategy of estrogenic supplementation is recommended for preventive reasons and, as it transpires from some studies, for enhancement of GnRH-a effectiveness.


Asunto(s)
Anticonceptivos Orales Combinados/uso terapéutico , Hormona Liberadora de Gonadotropina/análogos & derivados , Hormona Liberadora de Gonadotropina/agonistas , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Animales , Citocinas/sangre , Modelos Animales de Enfermedad , Quimioterapia Combinada , Estrógenos/sangre , Estrógenos/uso terapéutico , Femenino , Hormona Folículo Estimulante/sangre , Sustancias de Crecimiento/sangre , Humanos , Hormona Luteinizante/sangre , Síndrome del Ovario Poliquístico/etiología , Síndrome del Ovario Poliquístico/metabolismo , Ratas
5.
Mol Cell Endocrinol ; 119(1): 1-10, 1996 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-8793848

RESUMEN

Human chorionic somatomammotropin (CS) synthesis results from the independent expression of two homologous genes, CS-A and CS-B. A transcription enhancer factor-1 (TEF-1) element and an upstream 81 bp modulatory domain, containing repressor (RF-1) and derepressor (DF-1) activities, are important for efficient CS-B enhancer function in transfected placental JEG-3 cells. The equivalent region of the CS-A gene is not active. Although the TEF-1 element is conserved between the CS-A and CS-B genes, a single base substitution is present in the DF-1 element and two more are located between the RF-1 and DF-1 sites in a region we term AF-1. Repair of the DF-1 site increased CS-A enhancer function approximately 70-fold, but repair of previously uncharacterized AF-1 sequences was also required for full (CS-B like) enhancer activity. A 5 bp disruption of AF-1 sequences in the CS-B enhancer region, resulted in a 97% loss of stimulatory activity. The AF-1 sequences showed no intrinsic enhancer activity, however, they were able to significantly repress heterologous promoter activity stimulated by a TEF-1 enhancer element. A high affinity/specificity interaction between JEG-3 nuclear protein and AF-1 sequences was confirmed by gel mobility shift assay. By comparison to "wild type' AF-1 sequences, this interaction was competed to a lesser extent by both RF-1 and DF-1 elements, but not by mutated AF-1 sequences. The major protein binding to AF-1 sequences was estimated to be 23 kDa by UV crosslinking. These data indicate that enhancer activity can be generated by modulating binding events proximal to the TEF-1 element in the CS-A "enhancer' region and that coordinated binding of AF-1 and DF-1 are required for efficient (CS-B) enhancer activity.


Asunto(s)
Proteínas de Unión al ADN/genética , Elementos de Facilitación Genéticos , Lactógeno Placentario/genética , Secuencia de Bases , Reactivos de Enlaces Cruzados , ADN/metabolismo , Humanos , Datos de Secuencia Molecular , Células Tumorales Cultivadas , Rayos Ultravioleta
6.
Ann N Y Acad Sci ; 752: 406-16, 1995 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-7755284

RESUMEN

We used reverse transcriptase-polymerase chain reaction (RT-PCR) to clone fibroblast growth factor receptor (FGFR) 1 isoforms from embryonic mouse heart and as a more sensitive method to characterize FGFR1 RNA expression in embryonic and adult mouse hearts. We describe the cloning of both full-length short (2259 base pairs) and long (2526 base pairs) FGFR1 isoform cDNAs which generated 86 and 102 kilodalton proteins, respectively, following in vitro translation. An assessment of FGFR1 RNA indicates that FGFR1-IIIc is the major form in both the embryonic and adult heart but there is an approximately 8.5-fold decrease in RNA levels in the adult. Differential RNA blotting as well as RT-PCR analyses are consistent with a switch in the relative expression of the short versus long FGFR1 isoforms during heart development. The long isoforms are more abundant in the embryo and the short isoforms predominate in the adult. This may be important in the regulation of growth and development of the heart.


Asunto(s)
Expresión Génica , Miocardio/metabolismo , Proteínas Tirosina Quinasas Receptoras , Receptores de Factores de Crecimiento de Fibroblastos/biosíntesis , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Encéfalo/metabolismo , Clonación Molecular , Secuencia de Consenso , Cartilla de ADN , Embrión de Mamíferos , Exones , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Factor 2 de Crecimiento de Fibroblastos/fisiología , Corazón/embriología , Ratones , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos , Mapeo Restrictivo , Homología de Secuencia de Aminoácido
7.
J Mol Cell Cardiol ; 26(11): 1449-59, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7897669

RESUMEN

Basic (b) fibroblast growth factor (FGF) mediates various biological responses including mitogenesis and angiogenesis by binding to specific cell surface receptors of the tyrosine kinase family. The bFGF receptor-1 FGFR1) exists in short and long isoforms due to alternate RNA splicing. Minor alterations in the amino acid sequence have also led to reports of different FGFR1 isoforms in different tissues even in the same species. In the absence of any sequence for heart FGFR1 and accumulating evidence for a role of bFGF in heart growth and differentiation, we cloned FGFR1 from embryonic mouse hearts. Reverse transcriptase-polymerase chain reaction (RT-PCR) was used to generate full-length short (2259 base pairs) and long (2526 base pairs) forms of FGFR1 cDNAs which generated 86 and 102 kDa proteins, respectively, following in vitro translation. Embryonic mouse heart FGFR1 differed by seven amino acids from the reported sequence for mouse neuroepithelial FGFR1 and appeared more similar to human placental FGFR1. A single FGFR1 transcript of approximately 4.3 kb was seen in RNA isolated from embryonic as well as adult mouse hearts. There was a decrease (approximately 8.5-fold) in FGFR1 RNA levels in the adult. The majority of FGFR1 transcripts in the adult as well as embryonic heart contained exon IIIc (FGFR1-IIIc) which is associated with isoforms that display the highest affinity for bFGF. However, the relative ratio of short versus long FGFR1 RNA expression was 0.5 in the embryonic heart compared to 5.9 in the adult heart. These results indicate that: (i) structurally distinct short and long FGFR1 isoform RNAs are expressed in the embryonic and adult heart; (ii) FGFR1-IIIc is the major form of receptor expressed in the embryonic as well as adult heart; (iii) the transition from the embryo to the adult stage is associated with a decrease but not absence of FGFR1 RNA expression; and (iv) long FGFR1-isoforms are more abundant in the embryo while short FGFR1 isoforms predominate in the adult.


Asunto(s)
Corazón Fetal/metabolismo , Regulación del Desarrollo de la Expresión Génica , Corazón/crecimiento & desarrollo , Proteínas Musculares/biosíntesis , Miocardio/metabolismo , Empalme del ARN , Proteínas Tirosina Quinasas Receptoras , Receptores de Factores de Crecimiento de Fibroblastos/biosíntesis , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN Complementario/genética , Exones , Ratones , Datos de Secuencia Molecular , Proteínas Musculares/genética , Biosíntesis de Proteínas , Receptor Tipo 1 de Factor de Crecimiento de Fibroblastos , Receptores de Factores de Crecimiento de Fibroblastos/genética , Transcripción Genética
8.
Endocrinology ; 134(6): 2461-7, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7515000

RESUMEN

Attempts to assess human placental GH variant (hGH-V) and chorionic somatomammotropin (hCS) RNA in choriocarcinoma cell lines have been hampered by low levels of expression and limited sensitivity of RNA blotting analysis. We examined human choriocarcinoma BeWo, JAR, and JEG-3 cell lines as well as samples of complete hydatidiform moles for expression of members of the human GH (hGH) gene family using reverse transcriptase-polymerase chain reaction. A single and common set of primers was designed and used to detect products of the hGH/hCS genes as well as distinguish processed RNA from any contaminating DNA. Transcripts from the hCS genes hCS-A and -B were distinguished from placental hGH variant (hGH-V) and hCS-like (hCS-L) gene RNA by diagnostic restriction digestion of the polymerase chain reaction products. The expected pattern of hGH/hCS RNA expression was detected in term placenta, where hCS and hGH-V/hCS-L transcripts represented approximately 95% and approximately 5% of the total hGH/hCS RNA, respectively. The level of hCS RNA varied from 22-99% of the total hGH/hCS RNA in the neoplastic trophoblast samples, and variable levels of hGH-V and hCS-L RNA were also observed. In choriocarcinoma JAR cells, hGH-V RNA represented approximately 78% of the total hGH/hCS RNA compared to approximately 22% for hCS. Further, although low hCS-L RNA levels (< 1%) were found in term placenta and two of the hydatidiform moles, hCS-L transcripts represented 11% of the total hGH/hCS RNA in a third hydatidiform mole. Finally, in contrast to the detection of variable levels of hCS-L RNA in term placenta and hydatidiform mole samples, no hCS-L transcripts were detected in the three choriocarcinoma cell lines examined. These patterns reflect either deregulated hGH/hCS gene expression in neoplastic trophoblasts or differences that accompany the process of differentiation of trophoblast subpopulations. Regardless, this suggests that the control of hGH-V and hCS-L gene expression is distinct from that of the hCS-A and hCS-B genes and raises questions about the possible involvement of hGH/hCS family members in the pathology of placental abnormalities.


Asunto(s)
Coriocarcinoma/metabolismo , Expresión Génica , Hormona del Crecimiento/genética , Placenta/química , Lactógeno Placentario/genética , ARN/metabolismo , Secuencia de Bases , Femenino , Variación Genética , Hormona del Crecimiento/análisis , Humanos , Mola Hidatiforme/metabolismo , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Embarazo , ADN Polimerasa Dirigida por ARN , Células Tumorales Cultivadas , Neoplasias Uterinas/metabolismo
9.
Mol Endocrinol ; 8(4): 478-89, 1994 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8052268

RESUMEN

The human chorionic somatomammotropin genes (hCS-A and -B) are expressed at high levels in the syncytiotrophoblast during pregnancy. A 22-base-pair (bp) transcriptional enhancer factor-1 (TEF-1) element in a 1022-bp fragment of the hCS-B 3'-flanking DNA (nucleotides 1-1022) was shown to be important for efficient promoter activity in placental cells. However, the TEF-1 site used alone does not contain all of the information required for the complete enhancer activity seen with the 1022-bp fragment. A 241-bp region of the 1022-bp fragment (nucleotides 1-241) maintains full enhancer activity in placental cells. Interactions between placental nuclear factors and sequences distinct from the TEF-1 element (nucleotides 117-139) were identified by gel mobility shift assay using the up-stream region corresponding to nucleotides 1-80. Interaction between these factors and the TEF-1 element was indicated by competition of the 1-80 bp region for complex formation by a TEF-1 site. We mutated sequences within the 1-80 bp region of the 241-bp enhancer fragment and assessed the enhancer function of wild-type and modified 241-bp fragments. We identified a sequence (DF-1 site) upstream of the TEF-1 site which is required for hCS-B enhancer function. DF-1 derepresses a repressor mechanism present in the 241-bp fragment that inhibits TEF-1 activity. A component of this repressor mechanism (RF-1 site) is present in the 1-80 bp region adjacent to the DF-1 site. Gel mobility shift competition analysis shows that the RF-1 and DF-1 sites participate in the formation of a common complex or compete for common protein factors in a tissue-specific manner.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Elementos de Facilitación Genéticos , Regulación de la Expresión Génica , Proteínas Nucleares , Placenta/metabolismo , Lactógeno Placentario/genética , Secuencias Reguladoras de Ácidos Nucleicos , Factores de Transcripción/metabolismo , Secuencia de Bases , Sitios de Unión , Coriocarcinoma/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Genes Sintéticos , Células HeLa/metabolismo , Humanos , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Oligonucleótidos/síntesis química , Oligonucleótidos/metabolismo , Especificidad de Órganos , Regiones Promotoras Genéticas , Homología de Secuencia de Ácido Nucleico , Virus 40 de los Simios/genética , Factores de Transcripción de Dominio TEA , Células Tumorales Cultivadas , Neoplasias Uterinas/patología
10.
Endocrinology ; 132(2): 620-8, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7678796

RESUMEN

A human nonpituitary cell line grown under serum-free (sf) conditions (sfRamos Burkitt lymphoma cell line) has been reported to secrete a 29K PRL-like peptide which acts as an autocrine growth factor. Conditioned medium from these cells was examined for lactogenic activity using the Nb2 bioassay and RIAs specific for human GH (hGH) and hPRL. SfRamos conditioned medium stimulated the growth of Nb2 cells. Anti-hGH monoclonal antibodies but not anti-hPRL inhibited the mitogenic effect of sfRamos conditioned medium on Nb2 cells. Immunoreactive hGH but not hPRL was detected by RIA. Immunoprecipitation with anti-hGH polyclonal antibody followed by Western blot analysis with anti-hGH monoclonal antibody revealed a specific 22K band with the same mobility as pituitary hGH. Northern blot analysis with an hGH complementary DNA (cDNA) probe revealed a 1.0-kilobase transcript migrating coincident with pituitary hGH messenger RNA. A less abundant, 1.6-kilobase transcript was also observed. Reverse transcriptase-polymerase chain reaction using specific primers for the hGH cDNA generated the predicted 248-base pair band. Polymerase chain reaction sequencing of this fragment revealed sequence identity to the hGH-N cDNA, demonstrating conclusively the expression of the hGH-N gene in the sfRamos cell line.


Asunto(s)
Hormona del Crecimiento/genética , Anticuerpos , Secuencia de Bases , Northern Blotting , Southern Blotting , Western Blotting , Linfoma de Burkitt , Medio de Cultivo Libre de Suero , ADN de Neoplasias/análisis , ADN de Neoplasias/genética , Exones , Hormona del Crecimiento/análisis , Hormona del Crecimiento/biosíntesis , Humanos , Datos de Secuencia Molecular , Peso Molecular , Oligodesoxirribonucleótidos , Poli A/genética , Poli A/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , ARN/genética , ARN/aislamiento & purificación , ARN Mensajero , ARN Neoplásico/genética , ARN Neoplásico/aislamiento & purificación , Homología de Secuencia de Ácido Nucleico , Células Tumorales Cultivadas
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