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1.
Artigo em Inglês | MEDLINE | ID: mdl-32554829

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-10446901

RESUMO

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.


Assuntos
Proteínas de Ligação a DNA/fisiologia , Elementos Facilitadores Genéticos , Hormônio do Crescimento Humano/genética , Adeno-Hipófise/metabolismo , Fatores de Transcrição/fisiologia , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Coriocarcinoma , Deleção de Genes , Células HeLa , Humanos , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Ratos , Timidina Quinase/genética , Fator de Transcrição Pit-1 , Células Tumorais Cultivadas
3.
Mol Cell Endocrinol ; 157(1-2): 131-42, 1999 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-10619404

RESUMO

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.


Assuntos
Diabetes Gestacional/genética , Hormônio do Crescimento/genética , Hormônios Placentários/genética , Lactogênio Placentário/genética , Feminino , Variação Genética , Idade Gestacional , Humanos , Placenta/química , Gravidez , RNA/biossíntese , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo
4.
Eur J Contracept Reprod Health Care ; 2(4): 213-24, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9678076

RESUMO

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.


Assuntos
Anticoncepcionais Orais Combinados/uso terapêutico , Hormônio Liberador de Gonadotropina/análogos & derivados , Hormônio Liberador de Gonadotropina/agonistas , Síndrome do Ovário Policístico/tratamento farmacológico , Animais , Citocinas/sangue , Modelos Animais de Doenças , Quimioterapia Combinada , Estrogênios/sangue , Estrogênios/uso terapêutico , Feminino , Hormônio Foliculoestimulante/sangue , Substâncias de Crescimento/sangue , Humanos , Hormônio Luteinizante/sangue , Síndrome do Ovário Policístico/etiologia , Síndrome do Ovário Policístico/metabolismo , Ratos
5.
Mol Cell Endocrinol ; 119(1): 1-10, 1996 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-8793848

RESUMO

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.


Assuntos
Proteínas de Ligação a DNA/genética , Elementos Facilitadores Genéticos , Lactogênio Placentário/genética , Sequência de Bases , Reagentes de Ligações Cruzadas , DNA/metabolismo , Humanos , Dados de Sequência Molecular , Células Tumorais Cultivadas , Raios Ultravioleta
6.
Ann N Y Acad Sci ; 752: 406-16, 1995 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-7755284

RESUMO

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.


Assuntos
Expressão Gênica , Miocárdio/metabolismo , Receptores Proteína Tirosina Quinases , Receptores de Fatores de Crescimento de Fibroblastos/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Encéfalo/metabolismo , Clonagem Molecular , Sequência Consenso , Primers do DNA , Embrião de Mamíferos , Éxons , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator 2 de Crescimento de Fibroblastos/fisiologia , Coração/embriologia , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , RNA Mensageiro/análise , RNA Mensageiro/biossíntese , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos
7.
J Mol Cell Cardiol ; 26(11): 1449-59, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7897669

RESUMO

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.


Assuntos
Coração Fetal/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Coração/crescimento & desenvolvimento , Proteínas Musculares/biossíntese , Miocárdio/metabolismo , Splicing de RNA , Receptores Proteína Tirosina Quinases , Receptores de Fatores de Crescimento de Fibroblastos/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , Éxons , Camundongos , Dados de Sequência Molecular , Proteínas Musculares/genética , Biossíntese de Proteínas , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Receptores de Fatores de Crescimento de Fibroblastos/genética , Transcrição Gênica
8.
Endocrinology ; 134(6): 2461-7, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7515000

RESUMO

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.


Assuntos
Coriocarcinoma/metabolismo , Expressão Gênica , Hormônio do Crescimento/genética , Placenta/química , Lactogênio Placentário/genética , RNA/metabolismo , Sequência de Bases , Feminino , Variação Genética , Hormônio do Crescimento/análise , Humanos , Mola Hidatiforme/metabolismo , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Gravidez , DNA Polimerase Dirigida por RNA , Células Tumorais Cultivadas , Neoplasias Uterinas/metabolismo
9.
Mol Endocrinol ; 8(4): 478-89, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8052268

RESUMO

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.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica , Proteínas Nucleares , Placenta/metabolismo , Lactogênio Placentário/genética , Sequências Reguladoras de Ácido Nucleico , Fatores de Transcrição/metabolismo , Sequência de Bases , Sítios de Ligação , Coriocarcinoma/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Sintéticos , Células HeLa/metabolismo , Humanos , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Oligonucleotídeos/síntese química , Oligonucleotídeos/metabolismo , Especificidade de Órgãos , Regiões Promotoras Genéticas , Homologia de Sequência do Ácido Nucleico , Vírus 40 dos Símios/genética , Fatores de Transcrição de Domínio TEA , Células Tumorais Cultivadas , Neoplasias Uterinas/patologia
10.
Endocrinology ; 132(2): 620-8, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7678796

RESUMO

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.


Assuntos
Hormônio do Crescimento/genética , Anticorpos , Sequência de Bases , Northern Blotting , Southern Blotting , Western Blotting , Linfoma de Burkitt , Meios de Cultura Livres de Soro , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Éxons , Hormônio do Crescimento/análise , Hormônio do Crescimento/biossíntese , Humanos , Dados de Sequência Molecular , Peso Molecular , Oligodesoxirribonucleotídeos , Poli A/genética , Poli A/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , RNA/genética , RNA/isolamento & purificação , RNA Mensageiro , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Homologia de Sequência do Ácido Nucleico , Células Tumorais Cultivadas
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