RESUMO
BACKGROUND AND AIMS: Most gene expression studies examining the effect of obesity and weight loss have been performed using adipose tissue. However, the liver also plays a central role in maintaining energy balance. We wanted to study the effects of a hypocaloric diet on overall hepatic gene expression and metabolic risk factors. METHODS AND RESULTS: The study subjects were middle-aged, obese women. The diet intervention subjects (n=12) were on a hypocaloric, low-fat diet for 8 weeks with a daily energy intake of 5.0 MJ (1200 kcal), while the control subjects (n=19) maintained their weight. Liver biopsies were taken at the end of the diet period during a gallbladder operation. Hepatic gene expression was analyzed using microarrays by comparing the gene expression profiles from four subjects per group. A global decrease in gene expression was observed with 142 down-regulated genes and only one up-regulated gene in the diet intervention group. The diet resulted in a mean weight loss of 5% of body weight. Triglyceride and fasting insulin concentrations decreased significantly after the diet. CONCLUSIONS: The global decrease in hepatic gene expression was unexpected but the results are interesting, since they included several genes not previously linked to weight reduction. However, since the comparison was made only after the weight reduction, other factors in addition to weight loss may also have been involved in the differences in gene expression between the groups. The decrease in triglyceride and fasting plasma insulin concentrations is in accordance with results from previous weight-loss studies.
Assuntos
Dieta com Restrição de Gorduras , Expressão Gênica , Fígado/metabolismo , Obesidade/sangue , Obesidade/dietoterapia , Idoso , Regulação para Baixo , Jejum/sangue , Feminino , Humanos , Insulina/sangue , Análise em Microsséries , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Análise de Sequência com Séries de Oligonucleotídeos , Fatores de Risco , Triglicerídeos/sangue , Regulação para Cima , Redução de PesoRESUMO
Gene expression studies have demonstrated the altered expression level of placental angiogenesis related genes in severe pre-eclampsia (PE). In cord compression, the transportation of oxygen from the placenta to the fetus is blocked, and it is speculated that during blockade the originally hypoxic placenta may become hyperoxic. We compared the placental gene expression profiles of one pre-eclamptic patient with cord compression (the index patient) to the profiles of patients with PE and those of normal pregnancy controls (including one woman with cord compression). The gene expression of the cord compression PE patient resembled that observed in the normal pregnancies. We hypothesize that umbilical blockade may in a short period of time lead to placental hyperoxia, which in turn has an effect on angiogenic gene expression profile.
Assuntos
Neovascularização Fisiológica/genética , Placenta/metabolismo , Pré-Eclâmpsia/genética , Complicações Hematológicas na Gravidez/patologia , Cordão Umbilical/patologia , Adulto , Estudos de Casos e Controles , Feminino , Regulação da Expressão Gênica , Humanos , Cordão Nucal/genética , Circulação Placentária/genética , Circulação Placentária/fisiologia , Gravidez , Complicações Hematológicas na Gravidez/genéticaRESUMO
AIM: To undertake a large-scale analysis of the expression profiles of native human pulp tissue and odontoblasts, and search for genes expressed only in odontoblasts. METHODOLOGY: Microarray was performed to pooled pulp and odontoblasts of native human third molars and to pooled +/- TGF-beta1 cultured pulps and odontoblasts (137 teeth). The repeatability of microarray analysis was estimated by comparing the experimental pulp samples with expression profiles of two pulp samples downloaded from the GEO database. The genes expressed only in the experimental pulp samples or in odontoblasts were divided into categories, and the expression of selected odontoblast-specific genes of extracellular matrix (ECM) organization and biogenesis category was confirmed with RT-PCR and Western blot. RESULTS: A 85.3% repeatability was observed between pulp microarrays, demonstrating the high reliability of the technique. Overall 1595 probe sets were positive only in pulp and 904 only in odontoblasts. Sixteen expressed sequence tags (ESTs), which represent transcribed sequences encoding possibly unknown genes, were detected only in odontoblasts; two consistently expressed in all odontoblast samples. Matrilin 4 (MATN4) was the only ECM biogenesis and organization related gene detected in odontoblasts but not in pulp by microarray and RT-PCR. MATN4 protein expression only in odontoblasts was confirmed by Western blot. CONCLUSIONS: Pulp tissue and odontoblast gene expression profiling provides basic data for further, more detailed protein analysis. In addition, MATN4 and the two ESTs could serve as an odontoblast differentiation marker, e.g. in odontoblast stem cell research.
Assuntos
Polpa Dentária/metabolismo , Perfilação da Expressão Gênica/métodos , Odontoblastos/metabolismo , Biomarcadores/análise , Western Blotting , Células Cultivadas , Colágeno Tipo XI/genética , Etiquetas de Sequências Expressas/química , Matriz Extracelular/genética , Proteínas da Matriz Extracelular/genética , Humanos , Proteínas Matrilinas , Análise em Microsséries , Fosfoproteínas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sialoglicoproteínas/genética , Técnicas de Cultura de Tecidos , Transcrição Gênica/genética , Fator de Crescimento Transformador beta1/metabolismoRESUMO
We have isolated a 1,926-bp cDNA that encodes a novel polypeptide of 396 amino acid residues with a calculated molecular mass of 45.2 kDa. This MPPE1 polypeptide consists of a predicted signal sequence of 45 residues at the N-terminus, a 240-amino acid metallo-phosphoesterase domain, and a 24-amino acid transmembrane domain at the C-terminus. The genomic organization of the human MPPE1 gene proved to consist of 14 exons and to span about 27 kb. The gene was located on chromosome 18p11.2, adjacent to the G protein Golf alpha gene (GNAL), in tail-to-tail orientation, partially overlapping with the 3' UTR of the latter gene. MPPE1 is expressed as an mRNA of 2.2 kb in the brain, but not in any other tissues studied here. 3' RACE analysis defined a single functional polyadenylation site within the 3' UTR of the GNAL gene, while RT-PCR analysis revealed an alternatively spliced form of MPPE1, which included an additional exon located within the last intron. The alternatively spliced form encoded a truncated variant of MPPE1 with a calculated molecular mass of 38.8 kDa that lacks the C-terminal transmembrane domain.
Assuntos
Cromossomos Humanos Par 18/genética , DNA Complementar/genética , Éxons/genética , Íntrons/genética , Fosfoproteínas Fosfatases/genética , Regiões 3' não Traduzidas/genética , Sequência de Aminoácidos , Sequência de Bases , Northern Blotting , Clonagem Molecular , Perfilação da Expressão Gênica , Humanos , Dados de Sequência Molecular , Fosfoproteínas Fosfatases/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de SequênciaRESUMO
We have characterized a novel intronless human gene (C18orf2) which is embedded in intron 5 of the G-protein gene (GNAL) on chromosome 18p11. This gene codes for a 199 amino acid polypeptide with a predicted molecular weight of 22.1 kDa. It is highly homologous to a number of predicted developmental proteins in organisms ranging from yeasts to Drosophila. C18orf2 mRNA was found to be expressed in various tissues.
Assuntos
Cromossomos Humanos Par 18/genética , Sequência Conservada/genética , Proteínas Heterotriméricas de Ligação ao GTP/genética , Íntrons/genética , Fases de Leitura Aberta/genética , Proteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Etiquetas de Sequências Expressas , Subunidades alfa de Proteínas de Ligação ao GTP , Perfilação da Expressão Gênica , Humanos , Dados de Sequência Molecular , Mapeamento Físico do Cromossomo , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas/genética , Proteínas/química , RNA Mensageiro/análise , RNA Mensageiro/genética , Alinhamento de Sequência , SoftwareRESUMO
The sequence and genomic organization of the human Golfalpha (GNAL) gene were determined. The human GNAL gene was found to contain 12 coding exons, and it spans over 80 kb on chromosome 18p11. 5' RACE analysis suggested an additional transcription initiation start site. Sequence analysis of the putative promoter region revealed conserved binding sites for several transcription factors. Sequence analysis of the 3'-untranslated region revealed the presence of two Alu sequences and two polyadenylation signals. 3' RACE analysis confirmed the functionality of the most downstream poly-a signal. The human GNAL was found to be expressed as a single transcript of about 5.9 kb in the brain. One highly informative dinucleotide repeat was found in intron 5. Additionally, a processed pseudogene for asparagine synthetase was found about 6 kb upstream of the GNAL gene. Knowledge of the sequence and structure of the human GNAL gene provides essential information for further analysis of the GNAL locus at chromosome 18p11 which has been linked to bipolar disorder and schizophrenia.