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1.
Transl Psychiatry ; 7(5): e1114, 2017 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-28463242

RESUMO

There is growing evidence that the preconceptual lifestyle and other environmental exposures of a father can significantly alter the physiological and behavioral phenotypes of their children. We and others have shown that paternal preconception stress, regardless of whether the stress was experienced during early-life or adulthood, results in offspring with altered anxiety and depression-related behaviors, attributed to hypothalamic-pituitary-adrenal axis dysregulation. The transgenerational response to paternal preconceptual stress is believed to be mediated by sperm-borne small noncoding RNAs, specifically microRNAs. As physical activity confers physical and mental health benefits for the individual, we used a model of voluntary wheel-running and investigated the transgenerational response to paternal exercise. We found that male offspring of runners had suppressed reinstatement of juvenile fear memory, and reduced anxiety in the light-dark apparatus during adulthood. No changes in these affective behaviors were observed in female offspring. We were surprised to find that running had a limited impact on sperm-borne microRNAs. The levels of three unique microRNAs (miR-19b, miR-455 and miR-133a) were found to be altered in the sperm of runners. In addition, we discovered that the levels of two species of tRNA-derived RNAs (tDRs)-tRNA-Gly and tRNA-Pro-were also altered by running. Taken together, we believe this is the first evidence that paternal exercise is associated with an anxiolytic behavioral phenotype of male offspring and altered levels of small noncoding RNAs in sperm. These small noncoding RNAs are known to have an impact on post-transcriptional gene regulation and can thus change the developmental trajectory of offspring brains and associated affective behaviors.


Assuntos
Ansiedade/genética , Medo/psicologia , Transmissão Vertical de Doenças Infecciosas/veterinária , MicroRNAs/genética , Condicionamento Físico Animal/efeitos adversos , Espermatozoides/metabolismo , Animais , Ansiedade/psicologia , Depressão/genética , Depressão/psicologia , Exposição Ambiental/efeitos adversos , Feminino , Regulação da Expressão Gênica , Sistema Hipotálamo-Hipofisário/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Sistema Hipófise-Suprarrenal/fisiopatologia , Pequeno RNA não Traduzido
2.
Transl Psychiatry ; 6(6): e837, 2016 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-27300263

RESUMO

Recent studies have suggested that physiological and behavioral traits may be transgenerationally inherited through the paternal lineage, possibly via non-genomic signals derived from the sperm. To investigate how paternal stress might influence offspring behavioral phenotypes, a model of hypothalamic-pituitary-adrenal (HPA) axis dysregulation was used. Male breeders were administered water supplemented with corticosterone (CORT) for 4 weeks before mating with untreated female mice. Female, but not male, F1 offspring of CORT-treated fathers displayed altered fear extinction at 2 weeks of age. Only male F1 offspring exhibited altered patterns of ultrasonic vocalization at postnatal day 3 and, as adults, showed decreased time in open on the elevated-plus maze and time in light on the light-dark apparatus, suggesting a hyperanxiety-like behavioral phenotype due to paternal CORT treatment. Interestingly, expression of the paternally imprinted gene Igf2 was increased in the hippocampus of F1 male offspring but downregulated in female offspring. Male and female F2 offspring displayed increased time spent in the open arm of the elevated-plus maze, suggesting lower levels of anxiety compared with control animals. Only male F2 offspring showed increased immobility time on the forced-swim test and increased latency to feed on the novelty-supressed feeding test, suggesting a depression-like phenotype in these animals. Collectively, these data provide evidence that paternal CORT treatment alters anxiety and depression-related behaviors across multiple generations. Analysis of the small RNA profile in sperm from CORT-treated males revealed marked effects on the expression of small noncoding RNAs. Sperm from CORT-treated males contained elevated levels of three microRNAs, miR-98, miR-144 and miR-190b, which are predicted to interact with multiple growth factors, including Igf2 and Bdnf. Sustained elevation of glucocorticoids is therefore involved in the transmission of paternal stress-induced traits across generations in a process involving small noncoding RNA signals transmitted by the male germline.


Assuntos
Ansiedade/genética , Corticosterona/farmacologia , Depressão/genética , Sistema Hipotálamo-Hipofisário/fisiopatologia , Exposição Paterna , Fenótipo , Sistema Hipófise-Suprarrenal/fisiopatologia , Pequeno RNA não Traduzido/genética , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Animais , Ansiedade/fisiopatologia , Fator Neurotrófico Derivado do Encéfalo/genética , Depressão/fisiopatologia , Éxons , Medo/efeitos dos fármacos , Medo/fisiologia , Feminino , Expressão Gênica/genética , Expressão Gênica/fisiologia , Fator de Crescimento Insulin-Like II/genética , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Gravidez , Fatores Sexuais
3.
Nucleic Acids Res ; 38(Database issue): D525-31, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19850723

RESUMO

IntAct is an open-source, open data molecular interaction database and toolkit. Data is abstracted from the literature or from direct data depositions by expert curators following a deep annotation model providing a high level of detail. As of September 2009, IntAct contains over 200.000 curated binary interaction evidences. In response to the growing data volume and user requests, IntAct now provides a two-tiered view of the interaction data. The search interface allows the user to iteratively develop complex queries, exploiting the detailed annotation with hierarchical controlled vocabularies. Results are provided at any stage in a simplified, tabular view. Specialized views then allows 'zooming in' on the full annotation of interactions, interactors and their properties. IntAct source code and data are freely available at http://www.ebi.ac.uk/intact.


Assuntos
Biologia Computacional/métodos , Bases de Dados Genéticas , Bases de Dados de Proteínas , Proteínas/química , Animais , Biologia Computacional/tendências , Reações Falso-Positivas , Humanos , Armazenamento e Recuperação da Informação/métodos , Internet , Linguagens de Programação , Mapeamento de Interação de Proteínas/métodos , Estrutura Terciária de Proteína , Software , Interface Usuário-Computador , Vocabulário Controlado
4.
Neurobiol Aging ; 28(12): 1821-33, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17052803

RESUMO

Alzheimer disease (AD) is the most prominent cause of dementia in the elderly. To determine changes in the AD brain that may mediate the transition into dementia, the gene expression of approximately 10,000 full-length genes was compared in mild/moderate dementia cases to non-demented controls that exhibited high AD pathology. Including this latter group distinguishes this work from previous studies in that it allows analysis of early cognitive loss. Compared to non-demented high-pathology controls, the hippocampus of AD cases with mild/moderate dementia had increased gene expression of the inflammatory molecule major histocompatibility complex (MHC) II, as assessed with microarray analysis. MHC II protein levels were also increased and inversely correlated with cognitive ability. Interestingly, the mild/moderate AD dementia cases also exhibited decreased number of T cells in the hippocampus and the cortex compared to controls. In conclusion, transition into AD dementia correlates with increased MHC II(+) microglia-mediated immunity and is paradoxically paralleled by a decrease in T cell number, suggesting immune dysfunction.


Assuntos
Doença de Alzheimer/imunologia , Encéfalo/imunologia , Citocinas/imunologia , Demência/imunologia , Encefalite/imunologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Regulação da Expressão Gênica/imunologia , Humanos
5.
J Neuroimmunol ; 182(1-2): 22-31, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17070935

RESUMO

Melatonin modulates the expression of a number of genes related to inflammation and immunity. Declining levels of melatonin with age may thus relate to some of the changes in immune function that occur with age. mRNA expression levels in murine CNS were measured using oligonucleotide microarrays in order to determine whether a dietary melatonin supplement may modify age-related changes in the response to an inflammatory challenge. CB6F1 male mice were fed 40-ppm melatonin for 9 weeks prior to sacrifice at 26.5 months of age, and compared with age-matched untreated controls and 4.5-month-old controls. A subset of both young and old animals was injected i.p. with lipopolysaccharide (LPS). After 3 h, total RNA was extracted from whole brain (excluding brain stem and cerebellum), and individual samples were hybridized to Affymetrix Mouse 430-2.0 arrays. Data were analyzed in Dchip and GeneSpring. Melatonin treatment markedly altered the response in gene expression of older animals subjected to an LPS challenge. These changes in general, caused the response to more closely resemble that of young animals subjected to the same LPS challenge. Thus melatonin treatment effects a major shift in the response of the CNS to an inflammatory challenge, causing a transition to a more youthful mRNA expression profile.


Assuntos
Envelhecimento/fisiologia , Encéfalo/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Melatonina/farmacologia , Envelhecimento/metabolismo , Animais , Suplementos Nutricionais , Sinergismo Farmacológico , Expressão Gênica/efeitos dos fármacos , Injeções Intraperitoneais , Masculino , Melatonina/administração & dosagem , Camundongos , Camundongos Endogâmicos , Análise em Microsséries , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/metabolismo
6.
Bone Marrow Transplant ; 34(1): 77-84, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15133485

RESUMO

In all, 41 multiple myeloma (MM) patients received an antithymocyte globulin (ATG), fludarabine, and busulfan-based reduced intensity conditioning (RIC) for allogeneic stem cell transplantation (allo-SCT) from HLA-identical siblings. In total, 29 patients (70%) were in partial remission, one patient in complete remission, and 11 (27%) with progressive disease at the time of allo-SCT. Median time between diagnosis and allo-SCT was 24 months. The cumulative incidences of grade II-IV and grade III-IV acute graft-versus-host disease (GVHD) were 36% (95% CI, 21-51%) and 7% (95% CI, 2-20%), respectively. Overall, 10 patients developed limited chronic GVHD, whereas seven developed an extensive form (cumulative incidence, 41% (95% CI, 26-56%) at 2 years). With a median follow-up of 389 days, the overall cumulative incidence of transplant-related mortality (TRM) was 17% (95% CI, 6-28%). In all, 11 patients (27%) are in continuous complete remission, and the Kaplan-Meier estimates of overall survival (OS) and progression-free survival (PFS) at 2 years were 62% (95% CI, 47-76%) and 41% (95% CI, 23-62%), respectively. PFS and OS were significantly higher in patients with chronic GVHD as compared to patients without chronic GVHD (P=0.006 for PFS and P=0.01 for OS). Collectively, these data demonstrate that RIC allo-SCT can mediate a potentially curative graft-versus-myeloma effect with an acceptable incidence of toxicity and TRM.


Assuntos
Soro Antilinfocitário/administração & dosagem , Efeito Enxerto vs Tumor/efeitos dos fármacos , Transplante de Células-Tronco Hematopoéticas/métodos , Condicionamento Pré-Transplante/métodos , Vidarabina/análogos & derivados , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bussulfano/efeitos adversos , Feminino , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Incidência , Transfusão de Linfócitos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Transplante Homólogo , Resultado do Tratamento , Vidarabina/administração & dosagem
7.
Ann N Y Acad Sci ; 1035: 197-215, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15681809

RESUMO

Slowing the functional decline in the aging brain is not only relevant to nonpathological senescence but also to a broad range of neurodegenerative diseases. Although disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD) are not found in the young adult, they gradually manifest with increasing age. AD, in particular, is an increasing major public health concern as the population ages; therapies that delay disease onset will markedly reduce overall disease prevalence. Aging of the brain has been repeatedly associated with cumulative oxidative damage to macromolecules and to abnormal levels of inflammatory activity. Melatonin has attained increasing prominence as a candidate for ameliorating these changes occurring during senescence. Recent research has focused on supplementation with dietary melatonin designed to elucidate the specific key intracellular targets of age-related inflammatory events, and the optimal means of affording protection of these targets. This report summarizes the progress made in this area.


Assuntos
Envelhecimento/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Melatonina/administração & dosagem , Doenças Neurodegenerativas/tratamento farmacológico , Envelhecimento/fisiologia , Animais , Encéfalo/fisiopatologia , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Humanos , Inflamação/tratamento farmacológico , Inflamação/etiologia , Doenças Neurodegenerativas/complicações , Estresse Oxidativo/efeitos dos fármacos
8.
Neurobiol Dis ; 8(6): 1046-56, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11741400

RESUMO

Exercise has beneficial effects on brain function, including the promotion of plasticity and the enhancement of learning and memory performance. Previously we found that exercise increases the expression of certain neurotrophic factors including brain derived neurotrophic factor in the rat hippocampus. To further explore the molecular mechanisms underlying these changes, we used high-density oligonucleotide microarrays containing probe sets representing approximately 5000 genes to analyze the level of gene transcripts in the hippocampus of rats voluntary running for 3 weeks in comparison with sedentary animals. An improved statistical approach for the analysis of DNA microarray data, Cyber-T, was utilized in data analysis. Here we show that exercise leads to changes in the level of a large number of gene transcripts, many of which are known to be associated with neuronal activity, synaptic structure, and neuronal plasticity. Our data indicate that exercise elicits a differential gene expression pattern with significant changes in genes of relevance for brain function.


Assuntos
Regulação da Expressão Gênica/fisiologia , Hipocampo/metabolismo , Proteínas do Tecido Nervoso/genética , Plasticidade Neuronal/genética , Condicionamento Físico Animal/fisiologia , Esforço Físico/fisiologia , Transcrição Gênica/genética , Regulação para Cima/genética , Envelhecimento/genética , Envelhecimento/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Metabolismo Energético/genética , Ambiente Controlado , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Hipocampo/citologia , Sistema Imunitário/metabolismo , Masculino , Proteínas do Tecido Nervoso/biossíntese , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Transporte Proteico/genética , Ratos , Ratos Sprague-Dawley
9.
Bone Marrow Transplant ; 27(8): 837-42, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11477441

RESUMO

High-dose cyclophosphamide (HDC) has been shown to be an effective regimen for collecting PBPC in multiple myeloma (MM) patients, but the optimal dose to be used remains controversial. Two historical cohorts of MM patients who received G- or GM-CSF and HDC at the dose of either 7 g/m(2) (HDC7, n = 74) or 4 g/m (HDC4, n = 42) were compared. As patients in the HDC4 group were more likely to have received G-CSF than GM-CSF (P < 10(-3)) and fewer previous alkylating agents (P = 0.004), multivariate logistic regression analysis was performed. In the HDC4 group, patients had a shorter median duration of neutropenia (P < 10(-4)), fewer RBC (P < 10(-3)) and platelet transfusions (P < 10(-3)) with fewer patients with platelets <20 x 10(9)/l (P = 0.004). Moreover, fewer febrile episodes (P < 10(-3)) and less need of intravenous antibiotics (P < 10(-3)) were found in the HDC4 group. No statistical difference was observed with regard to CD34(+) cell collection efficiency. Thus, the use of HDC at the dose of 4 g/m(2) for the collection of PBPC in MM patients decreases hematological and extrahematological toxicity with an equivalent CD34(+) cell collection efficiency.


Assuntos
Ciclofosfamida/administração & dosagem , Ciclofosfamida/toxicidade , Mobilização de Células-Tronco Hematopoéticas/métodos , Mieloma Múltiplo/terapia , Adulto , Idoso , Antígenos CD34 , Estudos de Coortes , Sobrevivência de Enxerto , Mobilização de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Leucaférese , Pessoa de Meia-Idade , Mieloma Múltiplo/complicações , Fatores de Tempo
10.
J Mol Biol ; 293(5): 1039-53, 1999 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-10547284

RESUMO

In many Candida species, the leucine CUG codon is decoded by a tRNA with two unusual properties: it is a ser-tRNA and, uniquely, has guanosine at position 33 (G33). Using a combination of enzymatic (V1 RNase, RnI nuclease) and chemical (Pb(2+), imidazole) probing of the native Candida albicans ser-tRNACAG, we demonstrate that the overall tertiary structure of this tRNA resembles that of a ser-tRNA rather than a leu-tRNA, except within the anticodon arm where there is considerable disruption of the anticodon stem. Using non-modified in vitro transcripts of the C. albicans ser-tRNACAG carrying G, C, U or A at position 33, we demonstrate that it is specifically a G residue at this position that induces the atypical anticodon stem structure. Further quantitative evidence for an unusual structure in the anticodon arm of the G33-tRNA is provided by the observed change in kinetics of methylation of the G at position 37, by purified Escherichia coli m(1)G37 methyltransferase. We conclude that the anticodon arm distortion, induced by a guanosine base at position 33 in the anticodon loop of this novel tRNA, results in reduced decoding ability which has facilitated the evolution of this tRNA without extinction of the species encoding it.


Assuntos
Anticódon/química , Anticódon/genética , Candida albicans/genética , Conformação de Ácido Nucleico , RNA de Transferência de Serina/química , RNA de Transferência de Serina/genética , Anticódon/metabolismo , Sequência de Bases , Evolução Molecular , Código Genético/genética , Imidazóis/metabolismo , Chumbo/metabolismo , Metilação , Mutação/genética , Nucleosídeos/genética , Nucleosídeos/metabolismo , RNA Fúngico/química , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA de Transferência de Serina/metabolismo , Ribonucleases/metabolismo , Saccharomyces cerevisiae/genética , Soluções , tRNA Metiltransferases/metabolismo
11.
Life Sci ; 64(17): 1501-15, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10353615

RESUMO

Corticosteroids receptors were characterized and compared in central and peripheral tissues of two pig breeds, the Meishan (MS) and the Large White (LW) pigs, that display differences in the basal activity and stress-induced reactivity of the hypothalamic-pituitary-adrenal (HPA) axis. In vitro kinetic experiments on kidney and liver cytosols from adrenalectomized pigs allowed to identify two distinct corticosteroid receptors referred to as mineralocorticoid (MR) and glucocorticoid (GR) receptors. The binding specificities were determined for kidney and hippocampal MR and for liver and hippocampal GR. In hippocampus and peripheral tissues, cortisol showed a greater affinity for MR than for GR. As already described in the dog, mouse and human, dexamethasone and progesterone display a moderate affinity for MR. Putative differences in corticosteroid receptors binding capacities and affinities were investigated by saturation binding studies in specific regions implicated in the regulation of HPA axis (hippocampus and pituitary). The MS pigs evidenced higher densities of hippocampal MR, while LW pigs had higher densities of pituitary GR. Thus, this study suggests that a difference in the MR/GR balance in hippocampus and pituitary could be implicated in the different HPA activity between MS and LW pigs.


Assuntos
Receptores de Glucocorticoides/análise , Receptores de Mineralocorticoides/análise , Aldosterona/metabolismo , Animais , Dexametasona/metabolismo , Sistema Hipotálamo-Hipofisário/fisiologia , Masculino , Sistema Hipófise-Suprarrenal/fisiologia , Especificidade da Espécie , Suínos
12.
Mol Microbiol ; 25(2): 229-36, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9282735

RESUMO

We have identified a novel 399 bp repetitive DNA element (which we designate beta) 9bp upstream of a seryl-tRNA(CAG) gene in the genome of Candida albicans. There are two copies of the seryl-tRNA(CAG) gene, one on each homologue of chromosome VI, and the beta element is found upstream of one copy of the gene in C. albicans strain 2005E. The beta element is not present upstream of either copy of the seryl-tRNA(CAG) gene in eight other laboratory strains of C. albicans tested, but was detected in this location in several fresh clinical isolates. Southern blot analysis indicated that there are approximately eight copies of the beta element per diploid C. albicans genome and that it is a mobile element, being present on at least two different chromosomes. Three unique genomic DNA clones containing the beta element were isolated from strain 2005E; in each case, a different tRNA gene was found immediately adjacent to the beta element. Three new tRNA genes from C. albicans have thus been identified: tRNA(Asp), tRNA(Ala) and tRNA(Ile). The beta element shows no significant sequence homology to other known prokaryotic or eukaryotic repetitive elements, although an 8 bp repeat at the 3' end of the element is identical to that of the Ty3 retrotransposable element of Saccharomyces cerevisiae. We propose that the beta element is a solo long terminal repeat (LTR) sequence of a Ty3/gypsy-like transposable element in C. albicans that is closely associated with tRNA genes.


Assuntos
Candida albicans/genética , DNA Fúngico/genética , Genes Fúngicos , RNA de Transferência/genética , Sequência de Bases , Genoma Fúngico , Dados de Sequência Molecular , Sequências Repetitivas de Ácido Nucleico
13.
EMBO J ; 15(18): 5060-8, 1996 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-8890179

RESUMO

The human pathogenic yeast Candida albicans and a number of other Candida species translate the standard leucine CUG codon as serine. This is the latest addition to an increasing number of alterations to the standard genetic code which invalidate the theory that the code is frozen and universal. The unexpected finding that some organisms evolved alternative genetic codes raises two important questions: how have these alternative codes evolved and what evolutionary advantages could they create to allow for their selection? To address these questions in the context of serine CUG translation in C.albicans, we have searched for unique structural features in seryl-tRNA(CAG), which translates the leucine CUG codon as serine, and attempted to reconstruct the early stages of this genetic code switch in the closely related yeast species Saccharomyces cerevisiae. We show that a purine at position 33 (G33) in the C.albicans Ser-tRNA(CAG) anticodon loop, which replaces a conserved pyrimidine found in all other tRNAs, is a key structural element in the reassignment of the CUG codon from leucine to serine in that it decreases the decoding efficiency of the tRNA, thereby allowing cells to survive low level serine CUG translation. Expression of this tRNA in S.cerevisiae induces the stress response which allows cells to acquire thermotolerance. We argue that acquisition of thermotolerance may represent a positive selection for this genetic code change by allowing yeasts to adapt to sudden changes in environmental conditions and therefore colonize new ecological niches.


Assuntos
Candida albicans/genética , Códon , RNA Fúngico/metabolismo , RNA de Transferência de Serina/biossíntese , RNA de Transferência/metabolismo , Sequência de Bases , Northern Blotting , Humanos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , RNA Fúngico/química , RNA de Transferência/química , Saccharomyces cerevisiae , Serina-tRNA Ligase/metabolismo , Relação Estrutura-Atividade
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