Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
FASEB J ; 38(14): e23815, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38989587

RESUMO

To investigate how the fatty acid composition of brain phospholipids influences brain-specific processes, we leveraged the AdipoR2 (adiponectin receptor 2) knockout mouse model in which the brain is enlarged, and cellular membranes are excessively rich in saturated fatty acids. Lipidomics analysis of brains at 2, 7, and 18 months of age showed that phosphatidylcholines, which make up about two-thirds of all cerebrum membrane lipids, contain a gross excess of saturated fatty acids in AdipoR2 knockout mice, and that this is mostly attributed to an excess palmitic acid (C16:0) at the expense of oleic acid (C18:1), consistent with a defect in fatty acid desaturation and elongation in the mutant. Specifically, there was a ~12% increase in the overall saturated fatty acid content within phosphatidylcholines and a ~30% increase in phosphatidylcholines containing two palmitic acids. Phosphatidylethanolamines, sphingomyelins, ceramides, lactosylceramides, and dihydroceramides also showed an excess of saturated fatty acids in the AdipoR2 knockout mice while nervonic acid (C24:1) was enriched at the expense of shorter saturated fatty acids in glyceroceramides. Similar defects were found in the cerebellum and myelin sheaths. Histology showed that cell density is lower in the cerebrum of AdipoR2 knockout mice, but electron microscopy did not detect reproducible defects in the ultrastructure of cerebrum neurons, though proteomics analysis showed an enrichment of electron transport chain proteins in the cerebellum. Behavioral tests showed that older (33 weeks old) AdipoR2 knockout mice are hyperactive and anxious compared to control mice of a similar age. Also, in contrast to control mice, the AdipoR2 knockout mice do not gain weight in old age but do have normal lifespans. We conclude that an excess fatty acid saturation in brain phospholipids is accompanied by hyperactivity but seems otherwise well tolerated.


Assuntos
Envelhecimento , Encéfalo , Ácidos Graxos , Camundongos Knockout , Receptores de Adiponectina , Animais , Camundongos , Encéfalo/metabolismo , Ácidos Graxos/metabolismo , Envelhecimento/metabolismo , Receptores de Adiponectina/metabolismo , Receptores de Adiponectina/genética , Masculino , Camundongos Endogâmicos C57BL , Fosfatidilcolinas/metabolismo , Fosfolipídeos/metabolismo
2.
Eur J Oral Sci ; 132(3): e12985, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38520668

RESUMO

The association between dental caries experience and socioeconomic status, as reflected in income and educational level, is well known. However, some individuals maintain good health despite socioeconomic disadvantage. The aim of this qualitative study was to explore salutogenic (health-promoting) factors among healthy caries-free young adults of low socioeconomic status. Seventeen participants (11 women), 19-23 years of age, who were caries-free and of low socioeconomic status were interviewed in-depth. The interviews were transcribed verbatim and analysed using qualitative content analysis with an inductive approach. The theme revealed was 'Building trust and shifting responsibility from parent to child throughout children's development lays the salutogenic foundation for oral health', comprising three categories: (i) a basis for health; (ii) creating one's own path by testing wings; and (iii) developing resources for health. A feeling of trust was expressed, participants were confident in the unconditional support of their caregivers, and caregivers were trusting participants to be able to take control over their own oral health. Health-promotive factors were established not only by instilling healthy habits during childhood, but also by parental guidance through adolescence, enabling young adults to develop resources and assets to take control over their own health independently.


Assuntos
Saúde Bucal , Pesquisa Qualitativa , Classe Social , Confiança , Humanos , Feminino , Masculino , Adulto Jovem , Comportamentos Relacionados com a Saúde , Fatores Socioeconômicos , Atitude Frente a Saúde , Promoção da Saúde , Relações Pais-Filho , Cárie Dentária , Escolaridade , Higiene Bucal , Entrevistas como Assunto , Apoio Social
3.
Acta Odontol Scand ; 81(3): 176-185, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35811490

RESUMO

OBJECTIVE: To identify common resilience factors against non-communicable diseases (dental caries, diabetes type II, obesity and cardiovascular disease) among healthy individuals exposed to chronic adversity. MATERIALS AND METHODS: The databases MEDLINE (via PubMed), Scopus and CINAHL were searched. Observational studies in English assessing resilience factors among populations living in chronic adversity were included. Intervention studies, systematic reviews, non-original articles and qualitative studies were excluded. There were no restrictions regarding publication year or age. No meta-analysis could be done. Quality assessments were made with the Newcastle-Ottawa scale (NOS). RESULTS: A final total of 41 studies were included in this systematic review. The investigated health resilience factors were divided into the following domains: environmental (community and family) and individual (behavioural and psychosocial). A narrative synthesis of the results was made according to the domains. CONCLUSIONS: Individual psychosocial, family and environmental factors play a role as health resilience factors in populations living in chronic adversity. However, the inconclusive results suggest that these factors do not act in isolation but interplay in a complex manner and that their interaction may vary during the life course, in different contexts, and over time.


Assuntos
Cárie Dentária , Humanos , Nível de Saúde , Pesquisa Qualitativa
4.
Gerodontology ; 40(3): 390-397, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36404644

RESUMO

OBJECTIVE: Silver diamine fluoride (SDF) has been shown to be highly effective against caries, in particular for arresting root surface caries and for dentine caries in primary teeth. SDF may complement fluoride varnish routines for treatment of root caries in nursing home residents. The aim of this randomised, single-blinded, placebo-controlled trial was to evaluate the additive effect of a single annual application of SDF for prevention and treatment of incipient root caries in older adult nursing home residents. METHOD: Four hundred older adult nursing home residents (≥70 years old) with at least one exposed root surface (on teeth 15, 14, 13, 23, 24, or 25) were identified during routine dental examination visits in the domiciliary dental care setting. Eligible patients, who were able to understand the implication of consenting to the study, were invited to participate. Their cleaned root surfaces were randomly allocated to treatment with SDF (Advantage Arrest Silver Diamine Fluoride 38%, Advantage Arrest, LLC, Redmond, OR 97756, USA, Lot 16 152) or with placebo (tap water), each for 1 minute. RESULTS: Of the 400 eligible individuals, 42 declined to participate and two forms were destroyed. The remaining 356 participants (89.0%; mean age 87.7 years) were randomly allocated, with 174 going to the SDF group and 182 to the placebo group. At 1 year, 273 participants (76.7%) were available for assessment: 135 in the SDF group and 138 in the placebo group. By that time, 109 individuals (39.9%) demonstrated root caries progression or regression. Among those 118 (16.7%) of the 708 included root surfaces had developed caries There were no statistically significant differences in the primary outcome related to treatment with SDF or placebo, at either patient or root surface level. CONCLUSION: Based on the finding of this clinical trial, it is concluded that a single SDF application to complement a risk-based preventive programme including fluoride varnish applications did not have a statistically significant additional preventive effect on root caries development in a group of older adult nursing home residents with limited caries activity and cognitive capacity to cooperate in oral care activities.


Assuntos
Cárie Dentária , Cárie Radicular , Humanos , Idoso , Idoso de 80 Anos ou mais , Fluoretos Tópicos/uso terapêutico , Cárie Radicular/tratamento farmacológico , Cárie Radicular/prevenção & controle , Cariostáticos/uso terapêutico , Cárie Dentária/prevenção & controle , Fluoretos/uso terapêutico
5.
Hum Mol Genet ; 28(8): 1286-1297, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30561639

RESUMO

Molecular mechanisms governing the development of the human cochlea remain largely unknown. Through genome sequencing, we identified a homozygous FOXF2 variant c.325A>T (p.I109F) in a child with profound sensorineural hearing loss (SNHL) associated with incomplete partition type I anomaly of the cochlea. This variant is not found in public databases or in over 1000 ethnicity-matched control individuals. I109 is a highly conserved residue in the forkhead box (Fox) domain of FOXF2, a member of the Fox protein family of transcription factors that regulate the expression of genes involved in embryogenic development as well as adult life. Our in vitro studies show that the half-life of mutant FOXF2 is reduced compared to that of wild type. Foxf2 is expressed in the cochlea of developing and adult mice. The mouse knockout of Foxf2 shows shortened and malformed cochleae, in addition to altered shape of hair cells with innervation and planar cell polarity defects. Expressions of Eya1 and Pax3, genes essential for cochlear development, are reduced in the cochleae of Foxf2 knockout mice. We conclude that FOXF2 plays a major role in cochlear development and its dysfunction leads to SNHL and developmental anomalies of the cochlea in humans and mice.


Assuntos
Cóclea/embriologia , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/fisiologia , Adulto , Animais , Criança , Cóclea/metabolismo , Cóclea/fisiologia , Desenvolvimento Embrionário , Feminino , Células Ciliadas Auditivas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Nucleares/genética , Proteínas Nucleares/fisiologia , Organogênese , Fator de Transcrição PAX3/genética , Fator de Transcrição PAX3/fisiologia , Proteínas Tirosina Fosfatases/genética , Proteínas Tirosina Fosfatases/fisiologia , Transdução de Sinais/genética , Sequenciamento Completo do Genoma
6.
Development ; 142(19): 3307-20, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26293303

RESUMO

The molecular mechanisms orchestrating early mesoderm specification are still poorly understood. In particular, how alternate cell fate decisions are regulated in nascent mesoderm remains mostly unknown. In the present study, we investigated both in vitro in differentiating embryonic stem cells, and in vivo in gastrulating embryos, the lineage specification of early mesodermal precursors expressing or not the Forkhead transcription factor FOXF1. Our data revealed that FOXF1-expressing mesoderm is derived from FLK1(+) progenitors and that in vitro this transcription factor is expressed in smooth muscle and transiently in endothelial lineages, but not in hematopoietic cells. In gastrulating embryos, FOXF1 marks most extra-embryonic mesoderm derivatives including the chorion, the allantois, the amnion and a subset of endothelial cells. Similarly to the in vitro situation, FOXF1 expression is excluded from the blood islands and blood cells. Further analysis revealed an inverse correlation between hematopoietic potential and FOXF1 expression in vivo with increased commitment toward primitive erythropoiesis in Foxf1-deficient embryos, whereas FOXF1-enforced expression in vitro was shown to repress hematopoiesis. Altogether, our data establish that during gastrulation, FOXF1 marks all posterior primitive streak extra-embryonic mesoderm derivatives with the remarkable exception of the blood lineage. Our study further suggests that this transcription factor is implicated in actively restraining the specification of mesodermal progenitors to hematopoiesis.


Assuntos
Diferenciação Celular/fisiologia , Linhagem da Célula/fisiologia , Fatores de Transcrição Forkhead/metabolismo , Células-Tronco Hematopoéticas/citologia , Mesoderma/embriologia , Linhagem Celular , Citometria de Fluxo , Perfilação da Expressão Gênica , Técnicas de Transferência de Genes , Humanos , Imuno-Histoquímica , Análise em Microsséries , Plasmídeos/genética
8.
Dev Biol ; 415(1): 14-23, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27180663

RESUMO

The secondary palate separates the oral from the nasal cavity and its closure during embryonic development is sensitive to genetic perturbations. Mice with deleted Foxf2, encoding a forkhead transcription factor, are born with cleft palate, and an abnormal tongue morphology has been proposed as the underlying cause. Here, we show that Foxf2(-/-) maxillary explants cultured in vitro, in the absence of tongue and mandible, failed to close the secondary palate. Proliferation and collagen content were decreased in Foxf2(-/-) palatal shelf mesenchyme. Phosphorylation of Smad2/3 was reduced in mutant palatal shelf, diagnostic of attenuated canonical Tgfß signaling, whereas phosphorylation of p38 was increased. The amount of Tgfß2 protein was diminished, whereas the Tgfb2 mRNA level was unaltered. Expression of several genes encoding extracellular proteins important for Tgfß signaling were reduced in Foxf2(-)(/)(-) palatal shelves: a fibronectin splice-isoform essential for formation of extracellular Tgfß latency complexes; Tgfbr3 - or betaglycan - which acts as a co-receptor and an extracellular reservoir of Tgfß; and integrins αV and ß1, which are both Tgfß targets and required for activation of latent Tgfß. Decreased proliferation and reduced extracellular matrix content are consistent with diminished Tgfß signaling. We therefore propose that gene expression changes in palatal shelf mesenchyme that lead to reduced Tgfß signaling contribute to cleft palate in Foxf2(-)(/)(-) mice.


Assuntos
Fissura Palatina/embriologia , Fatores de Transcrição Forkhead/fisiologia , Mesoderma/embriologia , Palato/embriologia , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta2/fisiologia , Animais , Colágeno/fisiologia , Matriz Extracelular/fisiologia , Proteínas da Matriz Extracelular/fisiologia , Fibronectinas/fisiologia , Fatores de Transcrição Forkhead/deficiência , Fatores de Transcrição Forkhead/genética , Regulação da Expressão Gênica no Desenvolvimento , Integrinas/fisiologia , Mandíbula/embriologia , Maxila/embriologia , Mesoderma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Técnicas de Cultura de Órgãos , Fosforilação , Processamento de Proteína Pós-Traducional , Proteoglicanas/fisiologia , Receptores de Fatores de Crescimento Transformadores beta/fisiologia , Proteína Smad2/fisiologia , Proteína Smad3/fisiologia , Língua/anormalidades , Língua/embriologia , Fator de Crescimento Transformador beta2/biossíntese , Fator de Crescimento Transformador beta2/genética
9.
Gastroenterology ; 144(5): 1001-11, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23376422

RESUMO

BACKGROUND & AIMS: The stem cell niche at the base of the intestinal crypts, as well as stemness and high clonogenicity in colon cancer cells, depend on Wnt signaling to ß-catenin. Fibroblasts modulate the Wnt pathway in normal and neoplastic epithelial cells via unclear mechanisms. We investigated how in intestinal fibroblasts the forkhead transcription factor Foxf2 controls Wnt signaling to affect numbers of stem cells and formation and growth of adenomas in mice. METHODS: We created mice with different copy numbers of Foxf2 by generating Foxf2(-/+) mice and a transgenic strain, Tg(FOXF2). Adenoma formation was investigated in Apc(Min/+) mice, stem cells were counted in mice with the Lgr5-enhanced green fluorescent protein knock-in allele, proliferation was measured by incorporation of bromodeoxyuridine, Foxf2 and Sfrp1 were localized by immunohistochemistry, and signaling pathways were analyzed by quantitative polymerase chain reaction and immunoblot assays. RESULTS: Epithelial ß-catenin was stabilized in Foxf2(-/+) mice, resulting in increased number and size of adenomas. Tg(FOXF2) mice, however, were partially resistant to intestinal neoplasia and developed fewer and smaller adenomas; Foxf2(-/+) mice developed 24-fold more tumors than Tg(FOXF2) mice. Epithelial cells of Foxf2(-/+) mice also had higher numbers of Lgr5(+) stem cells and greater amounts of crypt cell proliferation and expression of Myc (a target of Wnt signaling) than Tg(FOXF2) mice. Expression of Sfrp1, which encodes an extracellular inhibitor of Wnt, in fibroblasts increased with copy number of Foxf2. CONCLUSIONS: Foxf2 is a fibroblast factor that inhibits paracrine Wnt signaling and restricts the crypt stem cell niche in intestines of mice. Loss of Foxf2 promotes adenoma formation and growth.


Assuntos
Adenoma/genética , Neoplasias do Colo/genética , Fibroblastos/metabolismo , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , RNA Neoplásico/genética , Células-Tronco/patologia , Adenoma/metabolismo , Adenoma/patologia , Alelos , Animais , Contagem de Células , Proliferação de Células , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Fibroblastos/patologia , Fatores de Transcrição Forkhead/biossíntese , Immunoblotting , Imuno-Histoquímica , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Neoplasias Experimentais , Reação em Cadeia da Polimerase , Células-Tronco/metabolismo , Células Tumorais Cultivadas , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/genética
10.
FASEB J ; 27(9): 3660-71, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23729594

RESUMO

Partial depletion of serine/threonine protein kinase 25 (STK25), a member of the Ste20 superfamily of kinases, increases lipid oxidation and glucose uptake in rodent myoblasts. Here we show that transgenic mice overexpressing STK25, when challenged with a high-fat diet, develop reduced glucose tolerance and insulin sensitivity compared to wild-type siblings, as evidenced by impairment in glucose and insulin tolerance tests as well as in euglycemic-hyperinsulinemic clamp studies. The fasting plasma insulin concentration was elevated in Stk25 transgenic mice compared to wild-type littermates (4.9±0.8 vs. 2.6±0.4 ng/ml after 17 wk on high-fat diet, P<0.05). Overexpression of STK25 decreased energy expenditure during the dark phase of observation (P<0.05), despite increased spontaneous activity. The oxidative capacity of skeletal muscle of transgenic carriers was reduced, as evidenced by altered expression of Cpt1, Acox1, and ACC. Hepatic triglycerides and glycogen were elevated (1.6- and 1.4-fold, respectively; P<0.05) and expression of key enzymes regulating lipogenesis (Fasn), glycogen synthesis (Gck), and gluconeogenesis (G6pc, Fbp1) was increased in the liver of the transgenic mice. Our findings suggest that overexpression of STK25 in conditions of excess dietary fuels associates with a shift in the metabolic balance in peripheral tissues from lipid oxidation to storage, leading to a systemic insulin resistance.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Glucose/metabolismo , Resistência à Insulina/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Adipócitos/metabolismo , Animais , Composição Corporal/genética , Composição Corporal/fisiologia , Calorimetria Indireta , Células Cultivadas , Teste de Tolerância a Glucose , Imuno-Histoquímica , Resistência à Insulina/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Serina-Treonina Quinases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Biochem Biophys Res Commun ; 437(2): 274-9, 2013 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-23811271

RESUMO

The very low density lipoprotein receptor (VLDLr) is highly upregulated during hypoxia in mouse cardiomyocytes and in human and mouse ischemic hearts causing a detrimental lipid accumulation. To know how the gene is regulated is important for future studies. In this study, we have thoroughly mapped the 5'-flanking region of the mouse VLDLr promoter and show that the hypoxia-mediated increase in VLDLr expression is dependent on Hif-1α binding to a hypoxia responsive element (HRE) located at -162 to -158bp 5'of translation start. We show that classical HRE sites and the previously described PPARγ and Sp1 binding are not involved in the hypoxia-induced regulation of the VLDLr promoter. Using a chromatin immunoprecipitation (ChIP) assay, we show that Hif-1α specifically binds and activates the mouse VLDLr promoter at the previously described non-classical HRE in HL-1 cells. We also show that the same HRE is present and active in response to hypoxia in human cardiomyocytes, however at a different location (-812bp from translation start). These results conclude that in the hypoxic hearts of mice and men, the VLDLr gene is regulated by a direct binding of Hif-1α to the VLDLr promoter.


Assuntos
Hipóxia/fisiopatologia , Receptores de LDL/fisiologia , Animais , Sítios de Ligação , Linhagem Celular , Primers do DNA , Camundongos , PPAR gama/metabolismo , Regiões Promotoras Genéticas , Receptores de LDL/genética , Fator de Transcrição Sp1/metabolismo
12.
Am J Med Genet A ; 161A(4): 764-70, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23444129

RESUMO

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACDMPV) is a congenital malformation that leads to severe pulmonary hypertension and respiratory failure. It has been associated with deletion of, or mutation in, FOXF1 on 16q24.1, a gene encoding a forkhead transcription factor expressed in the mesenchyme of the developing lung. Here we report on the identification of a pericentric inversion on chromosome 16 (p11.2q24.1) in a case of lethal ACDMPV with atrioventricular septal defect and duodenal atresia. Array-CGH indicated that the inversion is balanced, and FISH showed that the q-arm breakpoint occurs 134 ± 10 kb upstream (5'; centromeric) of FOXF1. This is suggestive of cis-regulatory elements located more than 130 kb 5' of FOXF1, and analysis of genome-wide data sets of chromatin modifications in two different cell types suggested that the FOXF1 regulatory domain covers more than 300 kb, and perhaps up to 433 kb, upstream of the gene, but only 3 kb downstream. The 588 kb gene-free region between FOXF1 and the next gene in the centromeric direction, IRF8, is highly conserved between species and divided into two distinct regulatory domains by an insulator element. Another putative insulator occurs just downstream of FOXF1. Our results further strengthen the association between FOXF1 and a spectrum of malformations that include ACDMPV, atrioventricular septal defects, and gastrointestinal atresia. Furthermore, the presented analysis aids in defining the critical genomic region for this syndrome.


Assuntos
Inversão Cromossômica , Fatores de Transcrição Forkhead/genética , Síndrome da Persistência do Padrão de Circulação Fetal/genética , Síndrome da Persistência do Padrão de Circulação Fetal/patologia , Autopsia , Cromossomos Humanos Par 16 , Hibridização Genômica Comparativa , Evolução Fatal , Feminino , Humanos , Hibridização in Situ Fluorescente , Recém-Nascido , Fatores Reguladores de Interferon/genética
13.
J Strength Cond Res ; 27(5): 1239-52, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22344058

RESUMO

The purpose of this study was to investigate and compare skiing economy and gross efficiency in cross-country skiers of different performance levels, ages and genders; male recreational skiers and elite senior and junior cross-country skiers of both genders. The skiers performed tests involving roller skiing on a treadmill using the gear 3 and diagonal stride techniques. The elite cross-country skiers were found to have better skiing economy and higher gross efficiency (5-18%) compared with the recreational skiers (p < 0.05) and the senior elite had better economy and higher efficiency (4-5%) than their junior counterparts (p < 0.05), whereas no differences could be found between the genders. Also, large ranges in economy and gross efficiency were found in all groups. It was concluded that, in addition to V[Combining Dot Above]O2peak, skiing economy and gross efficiency have a great influence on the differences in performance times between recreational and junior and senior elite cross-country skiers, as well as between individual skiers within the different categories. Thus, we recommend cross-country skiers at all performance levels to test not only V[Combining Dot Above]O2peak, but also skiing economy and efficiency.


Assuntos
Desempenho Atlético/fisiologia , Metabolismo Energético/fisiologia , Resistência Física/fisiologia , Esqui/fisiologia , Adolescente , Adulto , Fatores Etários , Teste de Esforço/métodos , Feminino , Humanos , Modelos Lineares , Masculino , Consumo de Oxigênio , Fatores Sexuais , Espirometria , Adulto Jovem
14.
Exp Mol Med ; 54(6): 753-764, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35668101

RESUMO

Differentiation of mesenchymal stem cells (MSCs) into osteoblasts is a critical process for proper skeletal development and acquisition/maintenance of bone mass. However, since this regulatory mechanism has not yet been fully elucidated, the treatment of severe osteoporosis and fractures is a challenge. Here, through a comprehensive analysis of gene expression during the differentiation of MSCs into osteoblasts, we show that the forkhead transcription factor Foxf2 is a crucial regulator of this process. Foxf2 expression transiently increased during MSC osteoblastic differentiation. Overexpression of Foxf2 in MSCs inhibited osteoblastic differentiation, and conversely, knockdown of Foxf2 expression promoted this process. Osteoprogenitor-specific Foxf2 knockout mice developed a high bone mass phenotype due to increased bone formation. RNA-seq analysis and molecular experiments revealed that Foxf2 regulation of bone formation is mediated by Wnt2b. Knockdown of Foxf2 in mouse femurs enhanced bone regeneration in vivo. FOXF2 expression was correlated with hip bone mineral density in postmenopausal women with low bone mass. Finally, inhibition of FOXF2 promoted osteoblastic differentiation of human MSCs. This study uncovers a critical role of Foxf2 in the differentiation of MSCs into osteoblasts and provides insight into the pathogenesis associated with bone-related diseases such as osteoporosis and nonunion after fracture.


Assuntos
Osteoporose , Via de Sinalização Wnt , Animais , Diferenciação Celular/genética , Feminino , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Glicoproteínas/metabolismo , Camundongos , Camundongos Knockout , Osteoblastos/metabolismo , Osteogênese/genética , Osteoporose/genética , Proteínas Wnt/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
15.
Nat Commun ; 13(1): 7162, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36418331

RESUMO

Cells and organisms require proper membrane composition to function and develop. Phospholipids are the major component of membranes and are primarily acquired through the diet. Given great variability in diet composition, cells must be able to deploy mechanisms that correct deviations from optimal membrane composition and properties. Here, using lipidomics and unbiased proteomics, we found that the embryonic lethality in mice lacking the fluidity regulators Adiponectin Receptors 1 and 2 (AdipoR1/2) is associated with aberrant high saturation of the membrane phospholipids. Using mouse embryonic fibroblasts (MEFs) derived from AdipoR1/2-KO embryos, human cell lines and the model organism C. elegans we found that, mechanistically, AdipoR1/2-derived sphingosine 1-phosphate (S1P) signals in parallel through S1PR3-SREBP1 and PPARγ to sustain the expression of the fatty acid desaturase SCD and maintain membrane properties. Thus, our work identifies an evolutionary conserved pathway by which cells and organisms achieve membrane homeostasis and adapt to a variable environment.


Assuntos
Caenorhabditis elegans , Receptores de Adiponectina , Humanos , Animais , Camundongos , Receptores de Adiponectina/genética , Fibroblastos , Lisofosfolipídeos , Homeostase , Desenvolvimento Embrionário/genética
16.
Biol Lett ; 7(6): 833-5, 2011 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-21613283

RESUMO

Migratory land birds perform extreme endurance flights when crossing ecological barriers, such as deserts, oceans and ice-caps. When travelling over benign areas, birds are expected to migrate by shorter flight steps, since carrying the heavy fuel loads needed for long non-stop flights comes at considerable cost. Here, we show that great snipes Gallinago media made long and fast non-stop flights (4300-6800 km in 48-96 h), not only over deserts and seas but also over wide areas of suitable habitats, which represents a previously unknown migration strategy among land birds. Furthermore, the great snipes achieved very high ground speeds (15-27 m s(-1)), which was not an effect of strong tailwind support, and we know of no other animal that travels this rapidly over such a long distance. Our results demonstrate that some migratory birds are prepared to accept extreme costs of strenuous exercise and large fuel loads, even when stopover sites are available along the route and there is little tailwind assistance. A strategy of storing a lot of energy before departure, even if migration is over benign habitats, may be advantageous owing to differential conditions of fuel deposition, predation or infection risk along the migration route.


Assuntos
Migração Animal , Charadriiformes/fisiologia , Voo Animal , Animais , Meio Ambiente , Sistemas de Informação Geográfica , Masculino , Fatores de Tempo
17.
Elife ; 102021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609283

RESUMO

Many diseases are linked to dysregulation of the striatum. Striatal function depends on neuronal compartmentation into striosomes and matrix. Striatal projection neurons are GABAergic medium spiny neurons (MSNs), subtyped by selective expression of receptors, neuropeptides, and other gene families. Neurogenesis of the striosome and matrix occurs in separate waves, but the factors regulating compartmentation and neuronal differentiation are largely unidentified. We performed RNA- and ATAC-seq on sorted striosome and matrix cells at postnatal day 3, using the Nr4a1-EGFP striosome reporter mouse. Focusing on the striosome, we validated the localization and/or role of Irx1, Foxf2, Olig2, and Stat1/2 in the developing striosome and the in vivo enhancer function of a striosome-specific open chromatin region 4.4 Kb downstream of Olig2. These data provide novel tools to dissect and manipulate the networks regulating MSN compartmentation and differentiation, including in human iPSC-derived striatal neurons for disease modeling and drug discovery.


Assuntos
Diferenciação Celular/genética , Neostriado/fisiologia , Neurônios/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Feminino , Humanos , Camundongos , Neostriado/patologia
18.
J Correct Health Care ; 24(4): 382-394, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30198371

RESUMO

The aim of the study was to describe oral health status as well as risk factors related to the oral health in a prison inmate population at admission. A sample of 186 men admitted to one of Sweden's prisons were examined and interviewed to collect information. The results indicate a high prevalence of untreated oral disease and oral health risk factors in the sample. Seventy-one percent of the study population indicated drug abuse. Only 4.9% were assessed with completely healthy periodontal tissues, and 66% showed at least one tooth with untreated caries. According to the current regulations on dental care for inmates, only 11% of the study population was entitled to basic dental treatment (except emergency).


Assuntos
Nível de Saúde , Saúde Bucal/estatística & dados numéricos , Prisioneiros/estatística & dados numéricos , Adulto , Cárie Dentária/epidemiologia , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Suécia/epidemiologia
19.
Trends Genet ; 19(6): 339-44, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12801727

RESUMO

Since the first forkhead (Fox) gene was identified, the importance of this family of transcription factors has increased steadily with the discoveries of the diverse range of developmental processes that they regulate in eukaryotes. Among other processes, the Fox factors are important in the establishment of the body axis and the development of tissues from all three germ layers. In this article, we present some of the recent data on this gene family with reference to selected phenotypes observed in patients and model organisms, and the sensitivity of developmental processes to alterations in forkhead gene dosage.


Assuntos
Segmento Anterior do Olho/anormalidades , Proteínas de Ligação a DNA/genética , Anormalidades do Olho/genética , Fatores de Transcrição/genética , Animais , Segmento Anterior do Olho/patologia , Córnea/anormalidades , Córnea/patologia , Proteínas de Ligação a DNA/fisiologia , Anormalidades do Olho/patologia , Fatores de Transcrição Forkhead , Humanos , Iris/anormalidades , Iris/patologia , Camundongos , Mutação , Fatores de Transcrição/fisiologia
20.
Mol Endocrinol ; 19(8): 1960-77, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15774500

RESUMO

Two-point mutations in the human glucocorticoid receptor have been studied by computer simulations to rationalize experimental data, where mutants comprising the V571M substitution improve both transcriptional activity and affinity for aldosterone despite large distances between the mutated residue and the coactivator-binding surface and ligand-binding pocket, respectively. Our molecular dynamics simulations show that the V571M mutation modifies the coactivator-binding site defined by helices 3, 4, and 12, and that specific structural rearrangement of the coactivator-binding site correlates well with transactivation data. A similar reorganization of the coactivator-binding cleft is observed in crystallographic structures of the estrogen receptor in the presence of coactivator peptide, compared with structures without peptide, indicating that induced fit for coactivator binding is a general phenomenon for nuclear receptors. These results suggest that the V571M substitution facilitates recruitment of coactivator protein by promotion of a conformational substate reducing the energetic penalty for the induced fit of the receptor-coactivator complex. Furthermore, our simulations of V571M mutants showed reduced fluctuations of residues lining the ligand-binding pocket. This indicates that a reduction of the entropic cost for ligand binding may explain the increased affinity of V571M mutants for certain ligands.


Assuntos
Mutação Puntual , Receptores de Glucocorticoides/genética , Sítio Alostérico , Sítios de Ligação , Núcleo Celular/metabolismo , Simulação por Computador , Cristalografia por Raios X , Dimerização , Desenho de Fármacos , Humanos , Ligação de Hidrogênio , Ligantes , Modelos Moleculares , Mutação , Peptídeos/química , Ligação Proteica , Conformação Proteica , Fatores de Tempo , Ativação Transcricional
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA