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1.
Am J Hum Genet ; 107(4): 589-595, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007198

RESUMO

In the post-genomic era, genomic medicine interventions as a key component of personalized medicine and tailored-made health care are greatly anticipated following recent scientific and technological advances. Indeed, large-scale sequencing efforts that explore human genomic variation have been initiated in several, mostly developed, countries across the globe, such as the United States, the United Kingdom, and a few others. Here, we highlight the successful implementation of large-scale national genomic initiatives, namely the Genome of Greece (GoGreece) and the DNA do Brasil (DNABr), aiming to emphasize the importance of implementing such initiatives in developing countries. Based on this experience, we also provide a roadmap for replicating these projects in other low-resource settings, thereby bringing genomic medicine in these countries closer to clinical fruition.


Assuntos
Genética Médica/organização & administração , Genoma Humano , Genômica/organização & administração , Saúde Única/legislação & jurisprudência , Medicina de Precisão/métodos , Brasil , Países em Desenvolvimento , Grécia , Sequenciamento de Nucleotídeos em Larga Escala/economia , Humanos , Saúde Pública/métodos , Reino Unido , Estados Unidos
2.
Exp Eye Res ; 204: 108461, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33516761

RESUMO

PURPOSE: Fibrillin-1 and -2 are major components of tissue microfibrils that compose the ciliary zonule and cornea. While mutations in human fibrillin-1 lead to ectopia lentis, a major manifestation of Marfan syndrome (MFS), in mice fibrillin-2 can compensate for reduced/lack of fibrillin-1 and maintain the integrity of ocular structures. Here we examine the consequences of a heterozygous dominant-negative mutation in the Fbn1 gene in the ocular system of the mgΔlpn mouse model for MFS. METHODS: Eyes from mgΔlpn and wild-type mice at 3 and 6 months of age were analyzed by histology. The ciliary zonule was analyzed by scanning electron microscopy (SEM) and immunofluorescence. RESULTS: Mutant mice presented a significantly larger distance of the ciliary body to the lens at 3 and 6 months of age when compared to wild-type, and ectopia lentis. Immunofluorescence and SEM corroborated those findings in MFS mice, revealing a disorganized mesh of microfibrils on the floor of the ciliary body. Moreover, mutant mice also had a larger volume of the anterior chamber, possibly due to excess aqueous humor. Finally, losartan treatment had limited efficacy in improving ocular phenotypes. CONCLUSIONS: In contrast with null or hypomorphic mutations, expression of a dominant-negative form of fibrillin-1 leads to disruption of microfibrils in the zonule of mice. This in turn causes lens dislocation and enlargement of the anterior chamber. Therefore, heterozygous mgΔlpn mice recapitulate the major ocular phenotypes of MFS and can be instrumental in understanding the development of the disease.


Assuntos
Modelos Animais de Doenças , Fibrilina-1/genética , Síndrome de Marfan/genética , Mutação/genética , Animais , Corpo Ciliar/metabolismo , Corpo Ciliar/ultraestrutura , Ectopia do Cristalino/genética , Proteínas da Matriz Extracelular/metabolismo , Cristalino/metabolismo , Cristalino/ultraestrutura , Ligamentos/ultraestrutura , Masculino , Síndrome de Marfan/patologia , Camundongos , Camundongos Endogâmicos C57BL , Microfibrilas/ultraestrutura , Proteínas dos Microfilamentos/metabolismo , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Fenótipo
3.
Exp Eye Res ; 194: 108001, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32173378

RESUMO

Elastic fibres provide tissues with elasticity and flexibility. In the healthy human cornea, elastic fibres are limited to the posterior region of the peripheral stroma, but their specific functional role remains elusive. Here, we examine the physical and structural characteristics of the cornea during development in the mgΔloxPneo dominant-negative mouse model for Marfan syndrome, in which the physiological extracellular matrix of its elastic-fibre rich tissues is disrupted by the presence of a dysfunctional fibrillin-1 glycoprotein. Optical coherence tomography demonstrated a reduced corneal thickness in the mutant compared to wild type mice from embryonic day 16.5 until adulthood. X-ray scattering and electron microscopy revealed a disruption to both the elastic fibre and collagen fibril ultrastructure in the knockout mice, as well as abnormally low levels of the proteoglycan decorin. It is suggested that these alterations might be a result of increased transforming growth factor beta signalling. To conclude, this study has demonstrated corneal structure and ultrastructure to be altered when fibrillin-1 is disrupted and has provided insights into the role of fibrillin-1 in developing a functional cornea.


Assuntos
Córnea/anormalidades , Matriz Extracelular/metabolismo , Síndrome de Marfan/patologia , Animais , Córnea/metabolismo , Córnea/ultraestrutura , Modelos Animais de Doenças , Elasticidade , Feminino , Fibrilina-1/metabolismo , Síndrome de Marfan/metabolismo , Camundongos , Camundongos Knockout , Microscopia Eletrônica , Tomografia de Coerência Óptica/métodos
4.
Front Cardiovasc Med ; 11: 1319164, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545339

RESUMO

Introduction: Ascending thoracic aortic aneurysms arise from pathological tissue remodeling that leads to abnormal wall dilation and increases the risk of fatal dissection/rupture. Large variability in disease manifestations across family members who carry a causative genetic variant for thoracic aortic aneurysms suggests that genetic modifiers may exacerbate clinical outcomes. Decreased perlecan expression in the aorta of mgΔlpn mice with severe Marfan syndrome phenotype advocates for exploring perlecan-encoding Hspg2 as a candidate modifier gene. Methods: To determine the effect of concurrent Hspg2 and Fbn1 mutations on the progression of thoracic aortopathy, we characterized the microstructure and passive mechanical response of the ascending thoracic aorta in female mice of four genetic backgrounds: wild-type, heterozygous with a mutation in the Fbn1 gene (mgΔlpn), heterozygous with a mutation in the Hspg2 gene (Hspg2+/-), and double mutants carrying both the Fbn1 and Hspg2 variants (dMut). Results: Elastic fiber fragmentation and medial disarray progress from the internal elastic lamina outward as the ascending thoracic aorta dilates in mgΔlpn and dMut mice. Concurrent increase in total collagen content relative to elastin reduces energy storage capacity and cyclic distensibility of aortic tissues from mice that carry the Fbn1 variant. Inherent circumferential tissue stiffening strongly correlates with the severity of aortic dilatation in mgΔlpn and dMut mice. Perlecan haploinsufficiency superimposed to the mgΔlpn mutation curbs the viability of dMut mice, increases the occurrence of aortic enlargement, and reduces the axial stretch in aortic tissues. Discussion: Overall, our findings show that dMut mice are more vulnerable than mgΔlpn mice without an Hspg2 mutation, yet later endpoints and additional structural and functional readouts are needed to identify causative mechanisms.

5.
Nat Genet ; 31(2): 216-20, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12032569

RESUMO

In mammals, epigenetic marks on the X chromosomes are involved in dosage compensation. Specifically, they are required for X chromosome inactivation (XCI), the random transcriptional silencing of one of the two X chromosomes in female cells during late blastocyst development. During natural reproduction, both X chromosomes are active in the female zygote. In somatic-cell cloning, however, the cloned embryos receive one active (Xa) and one inactive (Xi) X chromosome from the donor cells. Patterns of XCIhave been reported normal in cloned mice, but have yet to be investigated in other species. We examined allele-specific expression of the X-linked monoamine oxidase type A (MAOA) gene and the expression of nine additional X-linked genes in nine cloned XX calves. We found aberrant expression patterns in nine of ten X-linked genes and hypomethylation of Xist in organs of deceased clones. Analysis of MAOA expression in bovine placentae from natural reproduction revealed imprinted XCI with preferential inactivation of the paternal X chromosome. In contrast, we found random XCI in placentae of the deceased clones but completely skewed XCI in that of live clones. Thus, incomplete nuclear reprogramming may generate abnormal epigenetic marks on the X chromosomes of cloned cattle, affecting both random and imprinted XCI.


Assuntos
Clonagem de Organismos , Mecanismo Genético de Compensação de Dose , Cromossomo X/genética , Animais , Bovinos , Metilação de DNA , Feminino , Dados de Sequência Molecular , Monoaminoxidase/genética , RNA Longo não Codificante , RNA não Traduzido/genética , Fatores de Transcrição/genética
6.
Sci Adv ; 9(10): eabo0234, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36888716

RESUMO

Ecological conditions in the Amazon rainforests are historically favorable for the transmission of numerous tropical diseases, especially vector-borne diseases. The high diversity of pathogens likely contributes to the strong selective pressures for human survival and reproduction in this region. However, the genetic basis of human adaptation to this complex ecosystem remains unclear. This study investigates the possible footprints of genetic adaptation to the Amazon rainforest environment by analyzing the genomic data of 19 native populations. The results based on genomic and functional analysis showed an intense signal of natural selection in a set of genes related to Trypanosoma cruzi infection, which is the pathogen responsible for Chagas disease, a neglected tropical parasitic disease native to the Americas that is currently spreading worldwide.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Ecossistema , Doença de Chagas/genética , Doença de Chagas/parasitologia , Povos Indígenas
7.
Acta Physiol (Oxf) ; 237(1): e13889, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36164969

RESUMO

AIM: It has been suggested that the proliferation and early differentiation of myoblasts are impaired in Marfan syndrome (MFS) mice during muscle regeneration. However, the underlying cellular and molecular mechanisms remain poorly understood. Here, we investigated muscle regeneration in MFS mouse models by analyzing the influence of the fibrotic niche on satellite cell function. METHODS: In vivo, ex vivo, and in vitro experiments were performed. In addition, we evaluated the effect of the pharmacological inhibition of fibrosis using Ang-(1-7) on regenerating skeletal muscles of MFS mice. RESULTS: The skeletal muscle of MFS mice shows an increased accumulation of collagen fibers (81.2%), number of fibroblasts (157.1%), and Smad2/3 signaling (110.5%), as well as an aberrant number of fibro-adipogenic progenitor cells in response to injury compared with wild-type mice. There was an increased number of proinflammatory and anti-inflammatory macrophages (3.6- and 3.1-fold, respectively) in regenerating muscles of wild-type mice, but not in the regenerating muscles of MFS mice. Our data show that proliferation and differentiation of satellite cells are altered (p ≤ 0.05) in MFS mice. Myoblast transplantation assay revealed that the regenerating muscles from MFS mice have reduced satellite cell self-renewal capacity (74.7%). In addition, we found that treatment with Ang-(1-7) reduces fibrosis (71.6%) and ameliorates satellite cell dysfunction (p ≤ 0.05) and muscle contractile function (p ≤ 0.05) in MFS mice. CONCLUSION: The fibrotic niche, caused by Fbn1 mutations, reduces the myogenic potential of satellite cells, affecting structural and functional muscle regeneration. In addition, the fibrosis inhibitor Ang-(1-7) partially counteracts satellite cell abnormalities and restores myofiber size and contractile force in regenerating muscles.


Assuntos
Síndrome de Marfan , Células Satélites de Músculo Esquelético , Camundongos , Animais , Síndrome de Marfan/patologia , Músculo Esquelético/fisiologia , Células Satélites de Músculo Esquelético/fisiologia , Diferenciação Celular , Modelos Animais de Doenças , Regeneração/fisiologia , Fibrose
8.
PLoS One ; 18(5): e0285418, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37159453

RESUMO

Fibrillin-1 is a pivotal structural component of the kidney's glomerulus and peritubular tissue. Mutations in the fibrillin-1 gene result in Marfan syndrome (MFS), an autosomal dominant disease of the connective tissue. Although the kidney is not considered a classically affected organ in MFS, several case reports describe glomerular disease in patients. Therefore, this study aimed to characterize the kidney in the mgΔlpn-mouse model of MFS. Affected animals presented a significant reduction of glomerulus, glomerulus-capillary, and urinary space, and a significant reduction of fibrillin-1 and fibronectin in the glomerulus. Transmission electron microscopy and 3D-ultrastructure analysis revealed decreased amounts of microfibrils which also appeared fragmented in the MFS mice. Increased collagen fibers types I and III, MMP-9, and α-actin were also observed in affected animals, suggesting a tissue-remodeling process in the kidney. Video microscopy analysis showed an increase of microvessel distribution coupled with reduction of blood-flow velocity, while ultrasound flow analysis revealed significantly lower blood flow in the kidney artery and vein of the MFS mice. The structural and hemodynamic changes of the kidney indicate the presence of kidney remodeling and vascular resistance in this MFS model. Both processes are associated with hypertension which is expected to worsen the cardiovascular phenotype in MFS.


Assuntos
Síndrome de Marfan , Animais , Camundongos , Fibrilina-1/genética , Síndrome de Marfan/genética , Modelos Animais de Doenças , Rim , Matriz Extracelular , Colágeno Tipo I
9.
Stem Cell Reports ; 18(10): 1905-1912, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37774702

RESUMO

Identifying human leukocyte antigen (HLA) haplotype-homozygous donors for the generation of induced pluripotent stem (iPS) cell lines permits the construction of biobanks immunologically compatible with significant numbers of individuals for use in therapy. However, two questions must be addressed to create such a bank: how many cell lines are necessary to match most of the recipient population and how many people should be tested to find these donors? In Japan and the UK, 50 and 100 distinct HLA-A, -B, and -DRB1 triple-homozygous haplotypes would cover 90% of those populations, respectively. Using data from the Brazilian National Registry of Bone Marrow Donors (REDOME), encompassing 4,017,239 individuals, we identified 1,906 distinct triple-homozygous HLA haplotypes. In Brazil, 559 triple-homozygous cell lines cover 95% of the population, and 3.8 million people would have to be screened. Finally, we show the contribution of the 30 most frequent triple-homozygous HLA haplotypes in Brazil to populations of different countries.


Assuntos
Células-Tronco Pluripotentes Induzidas , Humanos , Brasil , Células-Tronco Pluripotentes Induzidas/metabolismo , Antígenos HLA/metabolismo , Antígenos HLA-A/genética , Antígenos HLA-A/metabolismo , Doadores de Tecidos , Antígenos de Histocompatibilidade Classe I/metabolismo , Haplótipos/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Alelos , Frequência do Gene
10.
Front Genet ; 13: 1016341, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36588788

RESUMO

Chronic Kidney Disease (CKD) is a public health problem that presents genetic and environmental risk factors. Two alleles in the Apolipoprotein L1 (APOL1) gene were associated with chronic kidney disease; these alleles are common in individuals of African ancestry but rare in European descendants. Genomic studies on Afro-Americans have indicated a higher prevalence and severity of chronic kidney disease in people of African ancestry when compared to other ethnic groups. However, estimates in low- and middle-income countries are still limited. Precision medicine approaches could improve clinical outcomes in carriers of risk alleles in the Apolipoprotein L1 gene through early diagnosis and specific therapies. Nevertheless, to enhance the definition of studies on these variants, it would be necessary to include individuals with different ancestry profiles in the sample, such as Latinos, African Americans, and Indigenous peoples. There is evidence that measuring genetic ancestry improves clinical care for admixed people. For chronic kidney disease, this knowledge could help establish public health strategies for monitoring patients and understanding the impact of the Apolipoprotein L1 genetic variants in admixed populations. Therefore, researchers need to develop resources, methodologies, and incentives for vulnerable and disadvantaged communities, to develop and implement precision medicine strategies and contribute to consolidating diversity in science and precision medicine in clinical practice.

11.
Cell Death Dis ; 13(4): 412, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35484113

RESUMO

In acquired immune aplastic anemia (AA), pathogenic cytotoxic Th1 cells are activated and expanded, driving an immune response against the hematopoietic stem and progenitor cells (HSPCs) that provokes cell depletion and causes bone marrow failure. However, additional HSPC defects may contribute to hematopoietic failure, reflecting on disease outcomes and response to immunosuppression. Here we derived induced pluripotent stem cells (iPSCs) from peripheral blood (PB) erythroblasts obtained from patients diagnosed with immune AA using non-integrating plasmids to model the disease. Erythroblasts were harvested after hematologic response to immunosuppression was achieved. Patients were screened for germline pathogenic variants in bone marrow failure-related genes and no variant was identified. Reprogramming was equally successful for erythroblasts collected from the three immune AA patients and the three healthy subjects. However, the hematopoietic differentiation potential of AA-iPSCs was significantly reduced both quantitatively and qualitatively as compared to healthy-iPSCs, reliably recapitulating disease: differentiation appeared to be more severely affected in cells from the two patients with partial response as compared to the one patient with complete response. Telomere elongation and the telomerase machinery were preserved during reprogramming and differentiation in all AA-iPSCs. Our results indicate that iPSCs are a reliable platform to model immune AA and recapitulate clinical phenotypes. We propose that the immune attack may cause specific epigenetic changes in the HSPCs that limit adequate proliferation and differentiation.


Assuntos
Anemia Aplástica , Células-Tronco Pluripotentes Induzidas , Anemia Aplástica/genética , Anemia Aplástica/patologia , Transtornos da Insuficiência da Medula Óssea , Diferenciação Celular , Células-Tronco Hematopoéticas/patologia , Humanos
12.
Stem Cell Rev Rep ; 18(4): 1337-1354, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35325357

RESUMO

Neurodevelopmental processes of pluripotent cells, such as proliferation and differentiation, are influenced by external natural forces. Despite the presence of biogenic magnetite nanoparticles in the central nervous system and constant exposure to the Earth's magnetic fields and other sources, there is scant knowledge regarding the role of electromagnetic stimuli in neurogenesis. Moreover, emerging applications of electrical and magnetic stimulation to treat neurological disorders emphasize the relevance of understanding the impact and mechanisms behind these stimuli. Here, the effects of magnetic nanoparticles (MNPs) in polymeric coatings and the static external magnetic field (EMF) were investigated on neural induction of murine embryonic stem cells (mESCs) and human induced pluripotent stem cells (hiPSCs). The results show that the presence of 0.5% MNPs in collagen-based coatings facilitates the migration and neuronal maturation of mESCs and hiPSCs in vitro. Furthermore, the application of 0.4 Tesla EMF perpendicularly to the cell culture plane, discernibly stimulates proliferation and guide fate decisions of the pluripotent stem cells, depending on the origin of stem cells and their developmental stage. Mechanistic analysis reveals that modulation of ionic homeostasis and the expression of proteins involved in cytostructural, liposomal and cell cycle checkpoint functions provide a principal underpinning for the impact of electromagnetic stimuli on neural lineage specification and proliferation. These findings not only explore the potential of the magnetic stimuli as neural differentiation and function modulator but also highlight the risks that immoderate magnetic stimulation may affect more susceptible neurons, such as dopaminergic neurons.


Assuntos
Células-Tronco Pluripotentes Induzidas , Nanopartículas de Magnetita , Células-Tronco Pluripotentes , Animais , Neurônios Dopaminérgicos , Humanos , Campos Magnéticos , Camundongos
13.
Sci Rep ; 11(1): 9624, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953270

RESUMO

In mammals, dosage compensation of X-linked gene expression between males and females is achieved by inactivation of a single X chromosome in females, while upregulation of the single active X in males and females leads to X:autosome dosage balance. Studies in human embryos revealed that random X chromosome inactivation starts at the preimplantation stage and is not complete by day 12 of development. Alternatively, others proposed that dosage compensation in human preimplantation embryos is achieved by dampening expression from the two X chromosomes in females. Here, we characterize X-linked dosage compensation in another primate, the marmoset (Callithrix jacchus). Analyzing scRNA-seq data from preimplantation embryos, we detected upregulation of XIST at the morula stage, where female embryos presented a significantly higher expression of XIST than males. Moreover, we show an increase of X-linked monoallelically expressed genes in female embryos between the morula and late blastocyst stages, indicative of XCI. Nevertheless, dosage compensation was not achieved by the late blastocyst stage. Finally, we show that X:autosome dosage compensation is achieved at the 8-cell stage, and demonstrate that X chromosome dampening in females does not take place in the marmoset. Our work contributes to the elucidation of primate X-linked dosage compensation.


Assuntos
Blastocisto/fisiologia , Mecanismo Genético de Compensação de Dose , Desenvolvimento Embrionário/fisiologia , Regulação para Cima , Inativação do Cromossomo X , Animais , Callithrix , Feminino , Masculino , Mórula/fisiologia , Análise de Sequência de RNA , Análise de Célula Única
14.
Stem Cell Res ; 53: 102384, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34088012

RESUMO

Hypertension is a complex multifactorial disease characterized by a chronic increase of arterial pressure. Ninety percent of the cases are idiopathic and thus classified as essential hypertension. Uncontrolled arterial pressure has devasting consequences including cardiac insufficiency, stroke, dementia, chronic renal disease, ischemic heart disease and death. The hiPSC lines described here from six hypertensive patients and three controls were characterized according to established criteria and were shown to maintain pluripotency, differentiation into the three germ layers and genomic integrity. These cell lines can contribute to the understanding of the molecular mechanisms involved in hypertension in different cell types.


Assuntos
Hipertensão , Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Diferenciação Celular , Linhagem Celular , Humanos
15.
Elife ; 102021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34403333

RESUMO

Human embryogenesis entails complex signalling interactions between embryonic and extra-embryonic cells. However, how extra-embryonic cells direct morphogenesis within the human embryo remains largely unknown due to a lack of relevant stem cell models. Here, we have established conditions to differentiate human pluripotent stem cells (hPSCs) into yolk sac-like cells (YSLCs) that resemble the post-implantation human hypoblast molecularly and functionally. YSLCs induce the expression of pluripotency and anterior ectoderm markers in human embryonic stem cells (hESCs) at the expense of mesoderm and endoderm markers. This activity is mediated by the release of BMP and WNT signalling pathway inhibitors, and, therefore, resembles the functioning of the anterior visceral endoderm signalling centre of the mouse embryo, which establishes the anterior-posterior axis. Our results implicate the yolk sac in epiblast cell fate specification in the human embryo and propose YSLCs as a tool for studying post-implantation human embryo development in vitro.


Assuntos
Camadas Germinativas/crescimento & desenvolvimento , Células-Tronco Pluripotentes/metabolismo , Saco Vitelino/crescimento & desenvolvimento , Animais , Linhagem Celular , Ectoderma/crescimento & desenvolvimento , Desenvolvimento Embrionário , Humanos , Camundongos
16.
Bone ; 152: 116073, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34171513

RESUMO

Marfan syndrome (MFS) is an autosomal dominant disease affecting cardiovascular, ocular and skeletal systems. It is caused by mutations in the fibrillin-1 (FBN1) gene, leading to structural defects of connective tissue and increased activation of TGF-ß. Angiotensin II (ang-II) is involved in TGF-ß activity and in bone mass regulation. Inhibition of TGF-ß signaling by blockage of the ang-II receptor 1 (AT1R) via losartan administration leads to improvement of cardiovascular and pulmonary phenotypes, but has no effect on skeletal phenotype in the haploinsufficient mouse model of MFS mgR, suggesting a distinct mechanism of pathogenesis in the skeletal system. Here we characterized the skeletal phenotypes of the dominant-negative model for MFS mgΔlpn and tested the effect of inhibition of ang-II signaling in improving those phenotypes. As previously shown, heterozygous mice present hyperkyphosis, however we now show that only males also present osteopenia. Inhibition of ang-II production by ramipril minimized the kyphotic deformity, but had no effect on bone microstructure in male mutant animals. Histological analysis revealed increased thickness of the anterior longitudinal ligament (ALL) of the spine in mutant animals (25.8 ± 6.3 vs. 29.7 ± 7.7 µm), coupled with a reduction in type I (164.1 ± 8.7 vs. 139.0 ± 4.4) and increase in type III (86.5 ± 10.2 vs. 140.4 ± 5.6) collagen in the extracellular matrix of this ligament. In addition, we identified in the MFS mice alterations in the erector spinae muscles which presented thinner muscle fibers (1035.0 ± 420.6 vs. 655.6 ± 239.5 µm2) surrounded by increased area of connective tissue (58.17 ± 6.52 vs. 105.0 ± 44.54 µm2). Interestingly, these phenotypes were ameliorated by ramipril treatment. Our results reveal a sex-dependency of bone phenotype in MFS, where females do not present alterations in bone microstructure. More importantly, they indicate that hyperkyphosis is not a result of osteopenia in the MFS mouse model, and suggest that incompetent spine ligaments and muscles are responsible for the development of that phenotype.


Assuntos
Cifose , Síndrome de Marfan , Animais , Feminino , Fibrilina-1/genética , Losartan/farmacologia , Masculino , Síndrome de Marfan/tratamento farmacológico , Síndrome de Marfan/genética , Camundongos , Fator de Crescimento Transformador beta
17.
Biochim Biophys Acta Mol Basis Dis ; 1866(1): 165587, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678158

RESUMO

Mechanisms whereby fibrillin-1 mutations determine thoracic aorta aneurysms/dissections (TAAD) in Marfan Syndrome (MFS) are unclear. Most aortic aneurysms evolve from mechanosignaling deregulation, converging to impaired vascular smooth muscle cell (VSMC) force-generating capacity accompanied by synthetic phenotype switch. However, little is known on VSMC mechanoresponses in MFS pathophysiology. Here, we investigated traction force-generating capacity in aortic VSMC cultured from 3-month old mg∆lpn MFS mice, together with morpho-functional and proteomic data. Cultured MFS-VSMC depicted marked phenotype changes vs. wild-type (WT) VSMC, with overexpressed cell proliferation markers but either lower (calponin-1) or higher (SM alpha-actin and SM22) differentiation marker expression. In parallel, the increased cell area and its complex non-fusiform shape suggested possible transition towards a mesenchymal-like phenotype, confirmed through several markers (e.g. N-cadherin, Slug). MFS-VSMC proteomic profile diverged from that of WT-VSMC particularly regarding lower expression of actin cytoskeleton-regulatory proteins. Accordingly, MFS-VSMC displayed lower traction force-generating capacity and impaired contractile moment at physiological substrate stiffness, and markedly attenuated traction force responses to enhanced substrate rigidity. Such impaired mechanoresponses correlated with decreased number, altered morphology and delocalization of focal adhesions, as well as disorganized actin stress fiber network vs. WT-VSMC. In VSMC cultured from 6-month-old mice, phenotype changes were attenuated and both WT-VSMC and MFS-VSMC generated less traction force, presumably involving VSMC aging, but without evident senescence. In summary, MFS-VSMC display impaired force-generating capacity accompanying a mesenchymal-like phenotype switch connected to impaired cytoskeleton/focal adhesion organization. Thus, MFS-associated TAAD involves mechanoresponse impairment common to other TAAD types, but through distinct mechanisms.


Assuntos
Síndrome de Marfan/patologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/patologia , Actinas/metabolismo , Animais , Aorta/metabolismo , Aorta/patologia , Aneurisma Aórtico/metabolismo , Aneurisma Aórtico/patologia , Biomarcadores/metabolismo , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Células Cultivadas , Citoesqueleto/metabolismo , Citoesqueleto/patologia , Modelos Animais de Doenças , Feminino , Fibrilina-1/metabolismo , Adesões Focais/metabolismo , Adesões Focais/patologia , Masculino , Síndrome de Marfan/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Fenótipo , Proteômica/métodos
18.
Stem Cell Res ; 41: 101640, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31710912

RESUMO

We describe generation of human induced pluripotent stem cell (hiPSC) lines of three unrelated idiopathic late onset Parkinson disease patients and two healthy controls above 60 years of age without neurological diseases nor Ashkenazi ancestry. Human iPSC were derived from peripheral blood-erythroblasts using integration free episomal plasmids carrying four reprogramming factors OCT4, SOX2, c-MYC, KLF4 and BCL-XL. The hiPSC lines were characterized according to established criteria.


Assuntos
Técnicas de Cultura de Células/métodos , Linhagem Celular/patologia , Células-Tronco Pluripotentes Induzidas/patologia , Doença de Parkinson/patologia , Idoso , Sequência de Bases , Humanos , Fator 4 Semelhante a Kruppel , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
19.
Stem Cell Res ; 39: 101519, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31401455

RESUMO

We describe the generation and characterization of hiPSC lines of one type 1-Gaucher disease patient with Parkinson's disease and two unrelated Parkinson's disease patients heterozygous for GBA mutations. Human iPSCs were derived from lymphocytes reprogrammed with Sendai virus carrying the reprogramming factors OCT3/4, SOX2, KLF4 and MYC. The hiPSC lines were characterized according to established criteria, and retained the original GBA mutations found in the respective patients.


Assuntos
Doença de Gaucher/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Doença de Parkinson/metabolismo , Células Cultivadas , Fibroblastos/citologia , Fibroblastos/metabolismo , Imunofluorescência , Instabilidade Genômica/fisiologia , Glucosilceramidase/genética , Heterozigoto , Humanos , Fator 4 Semelhante a Kruppel , Mutação/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
PLoS One ; 14(11): e0224581, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31725753

RESUMO

AIMS: Cardiovascular manifestations are a major cause of mortality in Marfan syndrome (MFS). Animal models that mimic the syndrome and its clinical variability are instrumental for understanding the genesis and risk factors for cardiovascular disease in MFS. This study used morphological and ultrastructural analysis to the understanding of the development of cardiovascular phenotypes of the the mgΔloxPneo model for MFS. METHODS AND RESULTS: We studied 6-month-old female mice of the 129/Sv background, 6 wild type (WT) and 24 heterozygous animals from the mgΔloxPneo model. Descending thoracic aortic aneurysm and/or dissection (dTAAD) were identified in 75% of the MFS animals, defining two subgroups: MFS with (MFS+) and without (MFS-) dTAAD. Both subgroups showed increased fragmentation of elastic fibers, predominance of type I collagen surrounding the elastic fiber and fragmentation of interlaminar fibers when compared to WT. However, only MFS animals with spine tortuosity developed aortic aneurysm/dissection. The aorta of MFS+ animals were more tortuous compared to those of MFS- and WT mice, possibly causing perturbations of the luminal blood flow. This was evidenced by the detection of diminished aorta-blood flow in MFS+. Accordingly, only MFS+ animals presented a process of concentric cardiac hypertrophy and a significantly decreased ratio of left and right ventricle lumen area. CONCLUSIONS: We show that mgΔloxPneo model mimics the vascular disease observed in MFS patients. Furthermore, the study indicates role of thoracic spine deformity in the development of aorta diseases. We suggest that degradation of support structures of the aortic wall; deficiency in the sustenance of the thoracic vertebrae; and their compression over the adjacent aorta resulting in disturbed blood flow is a triad of factors involved in the genesis of dissection/aneurysm of thoracic aorta.


Assuntos
Aneurisma da Aorta Torácica , Síndrome de Marfan , Coluna Vertebral , Animais , Aorta Torácica/metabolismo , Aorta Torácica/patologia , Aorta Torácica/fisiopatologia , Aneurisma da Aorta Torácica/genética , Aneurisma da Aorta Torácica/metabolismo , Aneurisma da Aorta Torácica/patologia , Velocidade do Fluxo Sanguíneo , Modelos Animais de Doenças , Tecido Elástico/metabolismo , Feminino , Humanos , Síndrome de Marfan/genética , Síndrome de Marfan/metabolismo , Síndrome de Marfan/patologia , Camundongos , Camundongos Transgênicos , Coluna Vertebral/metabolismo , Coluna Vertebral/patologia
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