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1.
EMBO J ; 43(18): 4000-4019, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39060516

RESUMO

Ageing and fertility are intertwined. Germline loss extends the lifespan in various organisms, termed gonadal longevity. However, the original longevity signal from the somatic gonad remains poorly understood. Here, we focused on the interaction between germline stem cells (GSCs) and their niche, the distal tip cells (DTCs), to explore the barely known longevity signal from the somatic gonad in C. elegans. We found that removing germline disrupts the cell adhesions between GSC and DTC, causing a significant transcriptomic change in DTC through hmp-2/ß-catenin and two GATA transcription factors, elt-3 and pqm-1 in this niche cell. Inhibiting elt-3 and pqm-1 in DTC suppresses gonadal longevity. Moreover, we further identified the TGF-ß ligand, tig-2, as the cytokine from DTC upon the loss of germline, which evokes the downstream gonadal longevity signalling throughout the body. Our findings thus reveal the source of the longevity signalling in response to germline removal, highlighting the stem cell niche as a critical signalling hub in ageing.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Adesão Celular , Células Germinativas , Longevidade , Nicho de Células-Tronco , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Células Germinativas/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Células-Tronco/metabolismo , Células-Tronco/citologia , Transdução de Sinais , Gônadas/metabolismo
2.
EMBO J ; 42(3): e111364, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36477743

RESUMO

Early embryonic development depends on proper utilization and clearance of maternal transcriptomes. How these processes are spatiotemporally regulated remains unclear. Here we show that nuclear RNA-binding protein Rbm14 and maternal mRNAs co-phase separate into cytoplasmic condensates to facilitate vertebrate blastula-to-gastrula development. In zebrafish, Rbm14 condensates were highly abundant in blastomeres and markedly reduced after prominent activation of zygotic transcription. They concentrated at spindle poles by associating with centrosomal γ-tubulin puncta and displayed mainly asymmetric divisions with a global symmetry across embryonic midline in 8- and 16-cell embryos. Their formation was dose-dependently stimulated by m6 A, but repressed by m5 C modification of the maternal mRNA. Furthermore, deadenylase Parn co-phase separated with these condensates, and this was required for deadenylation of the mRNAs in early blastomeres. Depletion of Rbm14 impaired embryonic cell differentiations and full activations of the zygotic genome in both zebrafish and mouse and resulted in developmental arrest at the blastula stage. Our results suggest that cytoplasmic Rbm14 condensate formation regulates early embryogenesis by facilitating deadenylation, protection, and mitotic allocation of m6 A-modified maternal mRNAs, and by releasing the poly(A)-less transcripts upon regulated disassembly to allow their re-polyadenylation and translation or clearance.


Assuntos
RNA Mensageiro Estocado , Peixe-Zebra , Animais , Feminino , Camundongos , Gravidez , Blastocisto/metabolismo , Blástula/metabolismo , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Mensageiro Estocado/genética , RNA Mensageiro Estocado/metabolismo
3.
Circ Res ; 134(5): 529-546, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38348657

RESUMO

BACKGROUND: Mature endothelial cells (ECs) are heterogeneous, with subtypes defined by tissue origin and position within the vascular bed (ie, artery, capillary, vein, and lymphatic). How this heterogeneity is established during the development of the vascular system, especially arteriovenous specification of ECs, remains incompletely characterized. METHODS: We used droplet-based single-cell RNA sequencing and multiplexed error-robust fluorescence in situ hybridization to define EC and EC progenitor subtypes from E9.5, E12.5, and E15.5 mouse embryos. We used trajectory inference to analyze the specification of arterial ECs (aECs) and venous ECs (vECs) from EC progenitors. Network analysis identified candidate transcriptional regulators of arteriovenous differentiation, which we tested by CRISPR (clustered regularly interspaced short palindromic repeats) loss of function in human-induced pluripotent stem cells undergoing directed differentiation to aECs or vECs (human-induced pluripotent stem cell-aECs or human-induced pluripotent stem cell-vECs). RESULTS: From the single-cell transcriptomes of 7682 E9.5 to E15.5 ECs, we identified 19 EC subtypes, including Etv2+Bnip3+ EC progenitors. Spatial transcriptomic analysis of 15 448 ECs provided orthogonal validation of these EC subtypes and established their spatial distribution. Most embryonic ECs were grouped by their vascular-bed types, while ECs from the brain, heart, liver, and lung were grouped by their tissue origins. Arterial (Eln, Dkk2, Vegfc, and Egfl8), venous (Fam174b and Clec14a), and capillary (Kcne3) marker genes were identified. Compared with aECs, embryonic vECs and capillary ECs shared fewer markers than their adult counterparts. Early capillary ECs with venous characteristics functioned as a branch point for differentiation of aEC and vEC lineages. CONCLUSIONS: Our results provide a spatiotemporal map of embryonic EC heterogeneity at single-cell resolution and demonstrate that the diversity of ECs in the embryo arises from both tissue origin and vascular-bed position. Developing aECs and vECs share common venous-featured capillary precursors and are regulated by distinct transcriptional regulatory networks.


Assuntos
Células Endoteliais , Canais de Potássio de Abertura Dependente da Tensão da Membrana , Adulto , Humanos , Animais , Camundongos , Hibridização in Situ Fluorescente , Artérias , Encéfalo , Veias
4.
Circulation ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39155863

RESUMO

BACKGROUND: Calmodulinopathies are rare inherited arrhythmia syndromes caused by dominant heterozygous variants in CALM1, CALM2, or CALM3, which each encode the identical CaM (calmodulin) protein. We hypothesized that antisense oligonucleotide (ASO)-mediated depletion of an affected calmodulin gene would ameliorate disease manifestations, whereas the other 2 calmodulin genes would preserve CaM level and function. METHODS: We tested this hypothesis using human induced pluripotent stem cell-derived cardiomyocyte and mouse models of CALM1 pathogenic variants. RESULTS: Human CALM1F142L/+ induced pluripotent stem cell-derived cardiomyocytes exhibited prolonged action potentials, modeling congenital long QT syndrome. CALM1 knockout or CALM1-depleting ASOs did not alter CaM protein level and normalized repolarization duration of CALM1F142L/+ induced pluripotent stem cell-derived cardiomyocytes. Similarly, an ASO targeting murine Calm1 depleted Calm1 transcript without affecting CaM protein level. This ASO alleviated drug-induced bidirectional ventricular tachycardia in CalmN98S/+ mice without a deleterious effect on cardiac electrical or contractile function. CONCLUSIONS: These results provide proof of concept that ASOs targeting individual calmodulin genes are potentially effective and safe therapies for calmodulinopathies.

5.
Med Sci Monit ; 30: e942324, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38494662

RESUMO

BACKGROUND Infection and chronic rejection remain major issues for kidney transplant recipients (KTRs). The present study aimed to explore the association of CD4+/CD8+ T cell ratio (CD4+/CD8+) and platelet/lymphocyte ratio (PLR) with long-term infection and chronic renal insufficiency in KTRs. MATERIAL AND METHODS KTRs admitted to a single hospital from June 2014 to December 2021 were divided into infected (164) and non-infected (107) groups based on clinical data. The levels of CD4+/CD8+, PLR, neutrophil/lymphocyte ratio (NLR), and C-reactive Protein (CRP) in KTRs with long-term infection, and their correlation with chronic kidney insufficiency, were analyzed. Survival analysis was used to evaluate the risk factors for long-term infection and chronic kidney insufficiency. RESULTS Spearman correlation analysis showed that chronic kidney insufficiency was positively correlated with PLR, and negatively correlated with CRP and CD4+/CD8+ (P<0.05). PLR was positively correlated with CRP, procalcitonin, erythrocyte sedimentation rate, and NLR, but negatively with CD4+/CD8+. CD4+/CD8+ was correlated with CRP, NLR, and PLR (P<0.05). Survival analysis and survival curves showed that PLR and CD4+/CD8+ were risk factors for long-term infection and chronic kidney insufficiency in KTRs (P<0.05). CONCLUSIONS CD4+/CD8+ and PLR were associated with long-term complications, and were risk factors for long-term infection and chronic kidney insufficiency in KTRs.


Assuntos
Transplante de Rim , Insuficiência Renal Crônica , Humanos , Transplante de Rim/efeitos adversos , Contagem de Plaquetas , Estudos Retrospectivos , Subpopulações de Linfócitos T/metabolismo , Proteína C-Reativa/metabolismo
6.
Biotechnol Lett ; 42(7): 1203-1210, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32300998

RESUMO

OBJECTIVE: To simplify CRISPR/Cas9 genome editing in the industrial filamentous fungus Trichoderma reesei based on in vivo guide RNA (gRNA) transcription. RESULTS: Two putative RNA polymerase III U6 snRNA genes were identified in the genome of T. reesei QM6a by BLASTN using Myceliophthora. thermophila U6 snRNA gene as the template. The regions approximately 500 bp upstream of two U6 genes were efficient promoters for the in vivo expression of gRNA. The CRISPR system consisting of Cas9 and in vivo synthesized gRNA under control of the T. reesei U6 snRNA promoters was sufficient to cause a frameshift mutation in the ura5 gene via non-homologous end-joining-mediated events. CONCLUSIONS: We report a simple gene editing method using a CRISPR/Cas9-coupled in vivo gRNA transcription system in T. reesei.


Assuntos
Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Genoma Fúngico/genética , Hypocreales/genética , RNA Guia de Cinetoplastídeos/genética , Regiões Promotoras Genéticas/genética , Transcrição Gênica/genética
7.
Fish Shellfish Immunol ; 81: 168-175, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30010014

RESUMO

Shrimps, which mainly rely on their innate immune system to response to infectious pathogens, have clottable proteins as an important component of this system. While transglutaminases (TGase) are found in Litopenaeus vannamei and constitute part of the coagulation system, the specific immune-related roles played by its functional domains in the immunoregulation of shrimp has not been well understood. In the present study, we report that the Ig-like domain of L. vannamei transglutaminase (TGase-C) is the main immune-related domain among the three functional domains, as it had higher bacterial agglutinative activity against Vibrio parahaemolyticus and Streptococcus iniae. Using Co-immunoprecipitation and LC-MS/MS analysis, TGase-C was shown to interact with 474 proteins, of which 52 proteins were annotated to L. vannamei. More than half of the L. vannamei annotated proteins have immune-related functions, including apoptosis. Further analysis using pull-down assay revealed that TGase-C interacted with CAP-3 (a homologue of caspase 3). In addition, siRNA-mediated knockdown of LvTGase significantly (p < 0.01) increased the expression level of LvCAP-3 coupled with a significant (p < 0.01) increase in caspase 3/7 activity, suggesting that probably LvTGase participates in shrimp immune response by modulating the activity of LvCAP-3. These findings thus suggest the Ig-like functional domain of L. vannamei's transglutaminase is the domain that is involved in immunoregulation in shrimp.


Assuntos
Proteínas de Artrópodes/imunologia , Imunidade Inata , Penaeidae/enzimologia , Penaeidae/imunologia , Transglutaminases/imunologia , Animais , Apoptose , Regulação da Expressão Gênica , Hemócitos , Filogenia , Alinhamento de Sequência , Streptococcus iniae , Vibrio parahaemolyticus
8.
Fish Shellfish Immunol ; 56: 450-458, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27506277

RESUMO

Hemocyanin (HMC) is a multifunctional protein which plays many essential roles in invertebrate organism. Recently more and more immune-related functions have been discovered on this protein. Here the shrimp was infected with Vibrio parahaemolyticus and the shrimp sera were analyzed by two-dimensional gel electrophoresis. Totally 15 spots were identified as significantly up-regulated spots and further analyzed by MALDI-TOF/TOF mass spectrometry (MS). Four of them were identified as HMC derived truncations (HMCS1, HMCS3, HMCS4 and HMCS5). The HMCS4 primary sequence was further determined via Edman N terminal sequencing, MALDI-TOF MS and amino acid sequence alignment. The result indicated that the HMCS4 was a 165aa fragment from shrimp HMC small subunit C-terminal. The HMCS4 immunological activities were further analyzed by agglutination experiment and antibacterial assay in vitro. The results showed that the recombinant HMCS4 (rHMCS4) had strong agglutination and antibacterial activities against pathogenic bacteria at the optimum bacteriostasis concentration. In addition, the HMCS4 immunological activities were explored via mortality assay in vivo. The shrimp was challenged with V. parahaemolyticus and rHMCS4 V. parahaemolyticus mixture separately. The shrimp mortality rate was significantly decreased at 96 h post-infection with rHMCS4 injection. Our data showed that shrimp HMC truncation generation upon infection was an effective immune response against invaded pathogens. Moreover, these findings may have some potential applications in shrimp industry.


Assuntos
Proteínas de Artrópodes/genética , Hemocianinas/genética , Penaeidae/genética , Vibrio parahaemolyticus/fisiologia , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/metabolismo , Sequência de Bases , Clonagem Molecular , DNA Complementar/genética , DNA Complementar/metabolismo , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Hemocianinas/química , Hemocianinas/metabolismo , Penaeidae/imunologia , Penaeidae/microbiologia , Filogenia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Alinhamento de Sequência
9.
Biochem Biophys Res Commun ; 460(3): 838-44, 2015 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-25824031

RESUMO

Both the intestine and liver develop from the endoderm, yet little is known how these two digestive organs share and differ in their developmental programs, at the molecular level. A classical forward genetic screen, with no gene bias, is an effective way to address this question by examining the defects of the intestine and liver in obtained mutants to assess mutated genes responsible for the development of either organ or both. We report here such a screen in zebrafish. ENU was used as the mutagen because of its high mutagenic efficiency and no site preference. Embryos were collected at 3.5 dpf for RNA whole mount in situ hybridization with a cocktail probe of the intestine marker ifabp and the liver marker lfabp to check phenotypes and determine their parental heterozygosis. A total of 52 F2 putative mutants were identified, and those with general developmental defects were aborted. To rule out non-inheritable phenotypes caused by high mutation background, F2 putative mutants were outcrossed with wild type fish and a re-screen in F3 generations was performed. After complementation tests between F3 mutants with similar phenotypes originating from the same F2 families, a total of 37 F3 mutant lines originated from 22 F2 families were identified after screening 78 mutagenized genomes. Classification of mutant phenotypes indicated that 31 out of the 37 mutants showed defects in both the intestine and liver. In addition, four "intestine specific mutants" and two "liver specific mutants" showed selectively more severe phenotype in the intestine and liver respectively. These results suggested that the intestine and liver share a substantial number of essential genes during both organs development in zebrafish. Further studies of the mutants are likely to shed more insights into the molecular basis of the digestive system development in the zebrafish and vertebrate.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Intestinos/embriologia , Fígado/embriologia , Mutação , Peixe-Zebra/genética , Animais , Feminino , Hibridização In Situ , Masculino , Organogênese
10.
BMC Nephrol ; 16: 10, 2015 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-25886601

RESUMO

BACKGROUND: Kimura's disease (KD) is a slowly progressing rare, benign inflammatory disorder of the soft tissues. It typically presents as subcutaneous tumor-like nodules, located most frequently in the head and neck region. KD is often accompanied by increased peripheral eosinophilia and elevated levels of serum immunoglobulin (Ig) E. There is renal involvement in approximately 12-16% of KD cases. We report the case of a 23-year-old Chinese man who was found to have KD associated with nephrotic syndrome. CASE PRESENTATION: A 23-year-old Chinese man presented with edema in both legs and a mass in ulnar side of his right upper arm on August 8(th) 2013. Before admission to our hospital, an ultrasound examination revealed swollen lymph nodes in the medial aspect of his right upper arm, proximal to the elbow. The patient was admitted on August 19(th) 2013 as a result of edema, severe proteinuria, and low serum albumin levels. He had a white blood cell count of 7.7 × 10(9) cells/L, 48.5% eosinophils, 4+ albuminuria, 24-hour urinary protein excretion 9.3 g, serum protein 50.3 g/L; serum albumin 16 g/L and IgE 1,510 IU/ml. A biopsy of the epitrochlear nodes revealed eosinophilic hyperplastic lymphogranulomatous tissue. A renal biopsy indicated focal segmental glomerulosclerosis (FSGS) (cellular variant) with no infiltration of eosinophil in renal interstitium. The results of immune-staining on the renal biopsy were negative for IgG, IgA, IgM, C3 and C1q. The electron microscopic analysis showed podocyte effacement. His final diagnosis was Kimura's disease associated with nephrotic syndrome. He received methylprednisolone therapy as well as symptomatic treatment, and was discharged with key indicators in normal range on September 17(th) 2013. During the year following, he had methylprednisolone at a maintenance dose of 8 mg/day, and no relapses occurred up to now. CONCLUSION: Methylprednisolone therapy is effective in KD associated with nephrotic syndrome, and long-term administration of methylprednisolone at maintenance dose may be a way to prevent relapses of KD.


Assuntos
Hiperplasia Angiolinfoide com Eosinofilia/diagnóstico , Hiperplasia Angiolinfoide com Eosinofilia/tratamento farmacológico , Glomerulosclerose Segmentar e Focal/complicações , Doenças Linfáticas/complicações , Metilprednisolona/uso terapêutico , Síndrome Nefrótica/complicações , Hiperplasia Angiolinfoide com Eosinofilia/complicações , Biópsia por Agulha , Seguimentos , Glomerulosclerose Segmentar e Focal/diagnóstico , Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Humanos , Imuno-Histoquímica , Testes de Função Renal , Doenças Linfáticas/diagnóstico , Doenças Linfáticas/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Masculino , Monitorização Fisiológica , Síndrome Nefrótica/diagnóstico , Síndrome Nefrótica/tratamento farmacológico , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
11.
Cell Biochem Biophys ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014186

RESUMO

Podocyte damage plays a crucial role in the occurrence and development of diabetic nephropathy (DN). Accumulating evidence suggests that dysregulation of transcription factors plays a crucial role in podocyte damage in DN. However, the biological functions and underlying mechanisms of most transcription factors in hyperglycemia-induced podocytes damage remain largely unknown. Through integrated analysis of data mining, bioinformatics, and RT-qPCR validation, we identified a critical transcription factor forkhead box F1 (FOXF1) implicated in DN progression. Moreover, we discovered that FOXF1 was extensively down-regulated in renal tissue and serum from DN patients as well as in high glucose (HG)-induced podocyte damage. Meanwhile, our findings showed that FOXF1 might be a viable diagnostic marker for DN patients. Functional experiments demonstrated that overexpression of FOXF1 strikingly enhanced proliferation, outstandingly suppressed apoptosis, and dramatically reduced inflammation and fibrosis in HG-induced podocytes damage. Mechanistically, we found that the downregulation of FOXF1 in HG-induced podocyte damage was caused by DNMT1 directly binding to FOXF1 promoter and mediating DNA hypermethylation to block FOXF1 transcriptional activity. Furthermore, we found that FOXF1 inhibited the transcriptional expression of miR-342-3p by binding to the promoter of miR-342, resulting in reduced sponge adsorption of miR-342-3p to E2F1, promoting the expression of E2F1, and thereby inhibiting HG-induced podocytes damage. In conclusion, our findings showed that blocking the FOXF1/miR-342-3p/E2F1 axis greatly alleviated HG-induced podocyte damage, which provided a fresh perspective on the pathogenesis and therapeutic strategies for DN patients.

12.
JCI Insight ; 9(14)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39133647

RESUMO

The aggregation and prion-like propagation of tau are the hallmarks of Alzheimer's disease (AD) and other tauopathies. However, the molecular mechanisms underlying the assembly and spread of tau pathology remain elusive. Epidemiological data show that exposure to fine particulate matter (PM2.5) is associated with an increased risk of AD. However, the molecular mechanisms remain unknown. Here, we showed that PM2.5 triggered the aggregation of tau and promoted the formation of tau fibrils. Injection of PM2.5-induced tau preformed fibrils (PFFs) into the hippocampus of tau P301S transgenic mice promoted the aggregation of tau and induced cognitive deficits and synaptic dysfunction. Furthermore, intranasal administration of PM2.5 exacerbated tau pathology and induced cognitive impairment in tau P301S mice. In conclusion, our results indicated that PM2.5 exposure promoted tau pathology and induced cognitive impairments. These results provide mechanistic insight into how PM2.5 increases the risk of AD.


Assuntos
Modelos Animais de Doenças , Hipocampo , Camundongos Transgênicos , Material Particulado , Tauopatias , Proteínas tau , Animais , Material Particulado/toxicidade , Proteínas tau/metabolismo , Camundongos , Tauopatias/metabolismo , Tauopatias/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Hipocampo/efeitos dos fármacos , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/patologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/etiologia , Agregação Patológica de Proteínas/metabolismo , Humanos , Masculino
13.
Fish Shellfish Immunol ; 34(1): 129-35, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23108257

RESUMO

Infectious diseases have seriously inhibited the aquaculture of mud crab Scylla paramamosain in southeastern China. Identification of the immune molecules and characterization of the defense mechanisms will be pivotal to the reduction of these diseases. Available data show that leucine-rich repeat (LRR) proteins play a crucial role in protein-protein interactions, recognition processes or immune reactions in both invertebrates and vertebrates. In the present study, we cloned and characterized a LRR cDNA from the mud crab Scylla paramamosain (SpLRR) by using the RACE strategy. Bioinformatics analysis predicted that SpLRR contains one open reading frame of 1893 bp and encodes a LRR protein of 630 amino acids with 17 LRR domains and 5 potential N-glycosylation sites. Further, SpLRR and other arthropod LRR proteins could be clustered into one branch in a phylogenetic tree. SpLRR transcripts were detected using RT-PCR from examined tissues including heart, gill, stomach, intestine, muscle and hemocytes, whereas not from hepatopancreas. More importantly, the SpLRR mRNA expression was up-regulated after infection with Vibrio alginolyticus, Beta streptococcus or Poly I: C for 12-48 h, suggesting a novel LRR homolog in crab might be associated with the resistance to pathogens. The result could be important for future investigation of crab immune defense mechanisms.


Assuntos
Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo , Braquiúros/genética , Braquiúros/imunologia , Proteínas/genética , Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Sequência de Bases , Braquiúros/química , Braquiúros/microbiologia , Clonagem Molecular , DNA Complementar/genética , Proteínas de Repetições Ricas em Leucina , Dados de Sequência Molecular , Especificidade de Órgãos , Filogenia , Poli I-C/farmacologia , Proteínas/química , RNA/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência , Streptococcus/fisiologia , Regulação para Cima , Vibrio alginolyticus/fisiologia
14.
Clin Nephrol ; 79(6): 477-83, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23391316

RESUMO

BACKGROUND: Malnutrition-Inflammation Score (MIS) has proved to predict the prospective mortality in maintenance hemodialysis (MHD) patients. However, its value of long-term mortality predictability in peritoneal dialysis (PD) patients has not been adequately studied. METHODS: A total of 155 chronic stable PD patients from November 2005 to December 2006 were enrolled. At baseline, the MIS, Subjective Global Assessment (SGA), as well as clinical, laboratory, and anthropometric parameters were recorded. All patients were followed until October 2009 to evaluate mortality as a primary outcome. RESULTS: The MIS correlated very well with SGA and other nutrition and inflammation markers. Patients with a higher MIS had a worse survival rate compared to those with lower MIS. After adjusting for potential confounding factors, one unit increase of MIS was associated with a 1.27-fold greater death risk (hazard ratio: 1.27, 95% confidence interval: 1.19 - 1.36; p < 0.001). MIS had a superior mortality predictability compared with SGA. Moreover, univariate and multivariate analyses denoted MIS, age, dialysis vintage, and comorbidities as independent predictors of total mortality. CONCLUSION: MIS is a promising marker for malnutrition inflammation assessment and an independent predictor of long-term mortality in Chinese PD patients.


Assuntos
Falência Renal Crônica/mortalidade , Desnutrição/mortalidade , Avaliação Nutricional , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , China/epidemiologia , Feminino , Seguimentos , Humanos , Inflamação/mortalidade , Falência Renal Crônica/complicações , Falência Renal Crônica/epidemiologia , Masculino , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Desnutrição/etiologia , Pessoa de Meia-Idade , Estado Nutricional , Diálise Peritoneal/mortalidade , Valor Preditivo dos Testes , Fatores de Risco , Sensibilidade e Especificidade , Taxa de Sobrevida , Fatores de Tempo
15.
Cell Rep ; 42(11): 113342, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37897723

RESUMO

The molecular mechanisms that trigger Tau aggregation in Alzheimer's disease (AD) remain elusive. Fungi, especially Saccharomyces cerevisiae (S. cerevisiae), can be found in brain samples from patients with AD. Here, we show that the yeast protein Ure2p from S. cerevisiae interacts with Tau and facilitates its aggregation. The Ure2p-seeded Tau fibrils are more potent in seeding Tau and causing neurotoxicity in vitro. When injected into the hippocampus of Tau P301S transgenic mice, the Ure2p-seeded Tau fibrils show enhanced seeding activity compared with pure Tau fibrils. Strikingly, intracranial injection of Ure2p fibrils promotes the aggregation of Tau and cognitive impairment in Tau P301S mice. Furthermore, intranasal infection of S. cerevisiae in the nasal cavity of Tau P301S mice accelerates the aggregation of Tau. Together, these observations indicate that the yeast protein Ure2p initiates Tau pathology. Our results provide a conceptual advance that non-mammalian prions may cross-seed mammalian prion-like proteins.


Assuntos
Glutationa Peroxidase , Príons , Proteínas de Saccharomyces cerevisiae , Tauopatias , Proteínas tau , Animais , Camundongos , Modelos Animais de Doenças , Camundongos Transgênicos , Príons/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas tau/metabolismo , Tauopatias/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Glutationa Peroxidase/metabolismo
16.
Appl Biochem Biotechnol ; 195(12): 7255-7276, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36988849

RESUMO

Emerging evidences suggested that circular RNAs (circRNAs) are involved in diabetic nephropathy (DN). Accumulating evidence had suggested that the degree of podocyte is a major prognostic determinant of DN progression. However, the function and in-depth mechanisms of hsa_circ_0001162 in podocyte injury of DN remain unclear. Hsa_circ_0001162 expression was detected by real-time quantitative PCR (RT-qPCR) in peripheral blood of DN patients and high glucose-induced podocytes injury model. The cell counting kit 8, 5-ethynyl-2'-deoxyuridine, flow cytometry with Annexin V-FITC/PI staining, caspase-3 activity assay Kit, enzyme linked immunosorbent assay (ELISA), RT-qPCR and western blotting were used to evaluate the effect of hsa_circ_0001162 / miR-149-5p / MMP9 axis on high glucose-induced podocyte injury. Mechanistically, dual luciferase reporter was used to confirm the relationship of miR-149-5p and hsa_circ_0001162 or MMP9. Furthermore, RNA-pull down and immunoprecipitation assay were implemented to verify the potential regulatory effects of EIF4A3 on biogenesis of hsa_circ_0001162. Our results showed that hsa_circ_0001162 was highly expressed in peripheral blood of DN patients and high glucose-induced podocytes injury model, and the knockdown of hsa_circ_0001162 increased the proliferation, inhibited the apoptosis, and suppressed inflammatory response in high glucose-induced podocytes injury. Mechanism studies demonstrated that EIF4A3 bound with flanking sequences of hsa_circ_0001162 to promote hsa_circ_0001162 expression, upregulated hsa_circ_0001162 increased the MMP9 expression via sponging miR-149-5p, thus aggravating the high glucose-induced podocytes injury. Overall, our data demonstrated that knockdown of hsa_circ_0001162 inhibited high glucose-induced podocytes injury by regulating miR-149-5p/MMP9 axis, and intervention of hsa_circ_0001162/miR-149-5p/MMP9 axis may be a potentially promising therapeutic strategy for podocyte injury in DN patients.


Assuntos
Nefropatias Diabéticas , MicroRNAs , Podócitos , Humanos , Metaloproteinase 9 da Matriz/genética , MicroRNAs/genética , Transdução de Sinais , Apoptose/genética , Glucose/toxicidade , Proliferação de Células , Fator de Iniciação 4A em Eucariotos , RNA Helicases DEAD-box
17.
Nat Commun ; 14(1): 6670, 2023 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-37865646

RESUMO

Triggering receptor expressed on myeloid cells 2 (TREM2) is a transmembrane protein that is predominantly expressed by microglia in the brain. The proteolytic shedding of TREM2 results in the release of soluble TREM2 (sTREM2), which is increased in the cerebrospinal fluid of patients with Alzheimer's disease (AD). It remains unknown whether sTREM2 regulates the pathogenesis of AD. Here we identified transgelin-2 (TG2) expressed on neurons as the receptor for sTREM2. The microglia-derived sTREM2 binds to TG2, induces RhoA phosphorylation at S188, and deactivates the RhoA-ROCK-GSK3ß pathway, ameliorating tau phosphorylation. The sTREM2 (77-89) fragment, which is the minimal active sequence of sTREM2 to activate TG2, mimics the inhibitory effect of sTREM2 on tau phosphorylation. Overexpression of sTREM2 or administration of the active peptide rescues tau pathology and behavioral defects in the tau P301S transgenic mice. Together, these findings demonstrate that the sTREM2-TG2 interaction mediates the cross-talk between microglia and neurons. sTREM2 and its active peptide may be a potential therapeutic intervention for tauopathies including AD.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Humanos , Doença de Alzheimer/metabolismo , Fosforilação , Camundongos Transgênicos , Peptídeos/metabolismo , Cognição , Proteínas tau/metabolismo , Biomarcadores/metabolismo , Peptídeos beta-Amiloides/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Receptores Imunológicos/genética , Receptores Imunológicos/metabolismo
18.
Biofactors ; 49(1): 173-184, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36070513

RESUMO

Diabetic encephalopathy (DE) is a common complication of type 2 diabetes (T2D), especially in those patients with long T2D history. Persistent high glucose (HG) stimulation leads to neuron damage and manifests like Alzheimer's disease's pathological features such as neurofilament tangle. However, the precise mechanism of high-glucose-induced tau hyperphosphorylation is not fully revealed. We here gave evidence that Disrupted in schizophrenia 1 protein (DISC1) could interact with glycogen synthase kinase 3ß (GSK3ß) and inhibit its activity to prevent tau hyperphosphorylation. By using DB/DB mice as animal model and HG-treated N2a cell as cell model, we found that DISC1 was downregulated both in vivo and in vitro, complicated with Tau hyperphosphorylation and GSK3ß activation. Further, we identified DISC1 interacted with GSK3ß by its 198th-237th amino acid residues. Overexpression of full length DISC1 but not mutated DISC1 lacking this domain could prevent HG induced tau hyperphosphorylation. Taken together, our work revealed DISC1 could be an important negative modulators of tau phosphorylation, and suggested that preservation of DISC1 could prevent HG induced neuron damage.


Assuntos
Diabetes Mellitus Tipo 2 , Proteínas tau , Camundongos , Animais , Proteínas tau/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Glucose , Fosforilação , Proteínas do Tecido Nervoso/metabolismo
19.
Nat Commun ; 14(1): 5675, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37709743

RESUMO

Understanding of the molecular drivers of lineage diversification and tissue patterning during primary germ layer development requires in-depth knowledge of the dynamic molecular trajectories of cell lineages across a series of developmental stages of gastrulation. Through computational modeling, we constructed at single-cell resolution, a spatio-temporal transcriptome of cell populations in the germ-layers of gastrula-stage mouse embryos. This molecular atlas enables the inference of molecular network activity underpinning the specification and differentiation of the germ-layer tissue lineages. Heterogeneity analysis of cellular composition at defined positions in the epiblast revealed progressive diversification of cell types. The single-cell transcriptome revealed an enhanced BMP signaling activity in the right-side mesoderm of late-gastrulation embryo. Perturbation of asymmetric BMP signaling activity at late gastrulation led to randomization of left-right molecular asymmetry in the lateral mesoderm of early-somite-stage embryo. These findings indicate the asymmetric BMP activity during gastrulation may be critical for the symmetry breaking process.


Assuntos
Lateralidade Funcional , Gastrulação , Animais , Camundongos , Gástrula , Camadas Germinativas , Mesoderma
20.
Cell Regen ; 12(1): 15, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36949352

RESUMO

Spinal motor neurons deficiency results in a series of devastating disorders such as amyotrophic lateral sclerosis (ALS), spinal muscular atrophy (SMA) and spinal cord injury (SCI). These disorders are currently incurable, while human pluripotent stem cells (hPSCs)-derived spinal motor neurons are promising but suffered from inappropriate regional identity and functional immaturity for the study and treatment of posterior spinal cord related injuries. In this study, we have established human spinal cord neural progenitor cells (hSCNPCs) via hPSCs differentiated neuromesodermal progenitors (NMPs) and demonstrated the hSCNPCs can be continuously expanded up to 40 passages. hSCNPCs can be rapidly differentiated into posterior spinal motor neurons with high efficiency. The functional maturity has been examined in detail. Moreover, a co-culture scheme which is compatible for both neural and muscular differentiation is developed to mimic the neuromuscular junction (NMJ) formation in vitro. Together, these studies highlight the potential avenues for generating clinically relevant spinal motor neurons and modeling neuromuscular diseases through our defined hSCNPCs.

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