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1.
Mol Cell ; 83(2): 186-202.e11, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36669479

RESUMO

PGC-1α is well established as a metazoan transcriptional coactivator of cellular adaptation in response to stress. However, the mechanisms by which PGC-1α activates gene transcription are incompletely understood. Here, we report that PGC-1α serves as a scaffold protein that physically and functionally connects the DNA-binding protein estrogen-related receptor α (ERRα), cap-binding protein 80 (CBP80), and Mediator to overcome promoter-proximal pausing of RNAPII and transcriptionally activate stress-response genes. We show that PGC-1α promotes pausing release in a two-arm mechanism (1) by recruiting the positive transcription elongation factor b (P-TEFb) and (2) by outcompeting the premature transcription termination complex Integrator. Using mice homozygous for five amino acid changes in the CBP80-binding motif (CBM) of PGC-1α that destroy CBM function, we show that efficient differentiation of primary myoblasts to myofibers and timely skeletal muscle regeneration after injury require PGC-1α binding to CBP80. Our findings reveal how PGC-1α activates stress-response gene transcription in a previously unanticipated pre-mRNA quality-control pathway.


Assuntos
Precursores de RNA , Fatores de Transcrição , Animais , Camundongos , Proteínas de Ligação a DNA/genética , Músculo Esquelético/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Regiões Promotoras Genéticas , Proteínas de Ligação ao Cap de RNA/genética , RNA Polimerase II/metabolismo , Precursores de RNA/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica
2.
Nucleic Acids Res ; 52(W1): W95-W101, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38738626

RESUMO

Thousands of long noncoding RNAs (lncRNAs) have been annotated via high-throughput RNA sequencing, yet only a small fraction have been functionally investigated. Genomic knockout is the mainstream strategy for studying the biological function of protein-coding genes and lncRNAs, whereas the complexity of the lncRNA locus, especially the natural antisense lncRNAs (NAT-lncRNAs), presents great challenges. Knocking out lncRNAs often results in unintended disruptions of neighboring protein-coding genes and small RNAs, leading to ambiguity in observing phenotypes and interpreting biological function. To address this issue, we launched LncRNAway, a user-friendly web tool based on the BESST (branchpoint to 3' splicing site targeting) method, to design sgRNAs for lncRNA knockout. LncRNAway not only provides specific and effective lncRNA knockout guidelines but also integrates genotyping primers and quantitative PCR primers designing, thereby streamlining experimental procedures of lncRNA function study. LncRNAway is freely available at https://www.lncrnaway.com.


Assuntos
Internet , RNA Guia de Sistemas CRISPR-Cas , RNA Longo não Codificante , Software , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Guia de Sistemas CRISPR-Cas/genética , Humanos , Técnicas de Inativação de Genes , Sistemas CRISPR-Cas
3.
Nucleic Acids Res ; 51(9): e49, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-36938886

RESUMO

Long noncoding RNAs (lncRNAs) are >200 nt RNA transcripts without protein-coding potential. LncRNAs can be categorized into intergenic, intronic, bidirectional, sense, and antisense lncRNAs based on the genomic localization to nearby protein-coding genes. The current CRISPR-based lncRNA knockout strategy works efficiently for lncRNAs distant from the protein-coding gene, whereas it causes genomic perturbance inevitably due to technical limitations. In this study, we introduce a novel lncRNA knockout strategy, BESST, by deleting the genomic DNA fragment from the branch point to the 3' splicing site in the last intron of the target lncRNA. The BESST knockout exhibited comparable or superior repressive efficiency to RNA silencing or conventional promoter-exon1 deletion. Significantly, the BESST knockout strategy minimized the intervention of adjacent/overlap protein-coding genes by removing an average of ∼130 bp from genomic DNA. Our data also found that the BESST knockout strategy causes lncRNA nuclear retention, resulting in decapping and deadenylation of the lncRNA poly(A) tail. Further study revealed that PABPN1 is essential for the BESST-mediated decay and subsequent poly(A) deadenylation and decapping. Together, the BESST knockout strategy provides a versatile tool for investigating gene function by generating knockout cells or animals with high specificity and efficiency.


Assuntos
Técnicas de Inativação de Genes , Genoma , Genômica , RNA Longo não Codificante , Animais , Éxons/genética , Técnicas de Inativação de Genes/métodos , Técnicas de Inativação de Genes/normas , Genoma/genética , Poli A/genética , Poli A/metabolismo , Proteína I de Ligação a Poli(A)/metabolismo , Regiões Promotoras Genéticas/genética , RNA Longo não Codificante/genética
4.
J Cell Mol Med ; 28(1): e18025, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38147352

RESUMO

Smooth muscle cell (SMC) contraction and vascular tone are modulated by phosphorylation and multiple modifications of the thick filament, and thin filament regulation of SMC contraction has been reported to involve extracellular regulated kinase (ERK). Previous studies in ferrets suggest that the actin-binding protein, calponin 1 (CNN1), acts as a scaffold linking protein kinase C (PKC), Raf, MEK and ERK, promoting PKC-dependent ERK activation. To gain further insight into this function of CNN1 in ERK activation and the regulation of SMC contractility in mice, we generated a novel Calponin 1 knockout mouse (Cnn1 KO) by a single base substitution in an intronic CArG box that preferentially abolishes expression of CNN1 in vascular SMCs. Using this new Cnn1 KO mouse, we show that ablation of CNN1 has two effects, depending on the cytosolic free calcium level: (1) in the presence of elevated intracellular calcium caused by agonist stimulation, Cnn1 KO mice display a reduced amplitude of stress and stiffness but an increase in agonist-induced ERK activation; and (2) during intracellular calcium depletion, in the presence of an agonist, Cnn1 KO mice exhibit increased duration of SM tone maintenance. Together, these results suggest that CNN1 plays an important and complex modulatory role in SMC contractile tone amplitude and maintenance.


Assuntos
Calponinas , Músculo Liso Vascular , Animais , Camundongos , Músculo Liso Vascular/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Cálcio/metabolismo , Furões/metabolismo , Contração Muscular , Camundongos Knockout , Miócitos de Músculo Liso/metabolismo
5.
Circulation ; 148(1): 47-67, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37199168

RESUMO

BACKGROUND: Activation of vascular smooth muscle cell (VSMC) inflammation is vital to initiate vascular disease. The role of human-specific long noncoding RNAs in VSMC inflammation is poorly understood. METHODS: Bulk RNA sequencing in differentiated human VSMCs revealed a novel human-specific long noncoding RNA called inflammatory MKL1 (megakaryoblastic leukemia 1) interacting long noncoding RNA (INKILN). INKILN expression was assessed in multiple in vitro and ex vivo models of VSMC phenotypic modulation as well as human atherosclerosis and abdominal aortic aneurysm. The transcriptional regulation of INKILN was verified through luciferase reporter and chromatin immunoprecipitation assays. Loss-of-function and gain-of-function studies and multiple RNA-protein and protein-protein interaction assays were used to uncover a mechanistic role of INKILN in the VSMC proinflammatory gene program. Bacterial artificial chromosome transgenic mice were used to study INKILN expression and function in ligation injury-induced neointimal formation. RESULTS: INKILN expression is downregulated in contractile VSMCs and induced in human atherosclerosis and abdominal aortic aneurysm. INKILN is transcriptionally activated by the p65 pathway, partially through a predicted NF-κB (nuclear factor kappa B) site within its proximal promoter. INKILN activates proinflammatory gene expression in cultured human VSMCs and ex vivo cultured vessels. INKILN physically interacts with and stabilizes MKL1, a key activator of VSMC inflammation through the p65/NF-κB pathway. INKILN depletion blocks interleukin-1ß-induced nuclear localization of both p65 and MKL1. Knockdown of INKILN abolishes the physical interaction between p65 and MKL1 and the luciferase activity of an NF-κB reporter. Furthermore, INKILN knockdown enhances MKL1 ubiquitination through reduced physical interaction with the deubiquitinating enzyme USP10 (ubiquitin-specific peptidase 10). INKILN is induced in injured carotid arteries and exacerbates ligation injury-induced neointimal formation in bacterial artificial chromosome transgenic mice. CONCLUSIONS: These findings elucidate an important pathway of VSMC inflammation involving an INKILN/MKL1/USP10 regulatory axis. Human bacterial artificial chromosome transgenic mice offer a novel and physiologically relevant approach for investigating human-specific long noncoding RNAs under vascular disease conditions.


Assuntos
Aneurisma da Aorta Abdominal , RNA Longo não Codificante , Animais , Humanos , Camundongos , Aneurisma da Aorta Abdominal/metabolismo , Proliferação de Células , Células Cultivadas , Inflamação/genética , Inflamação/metabolismo , Luciferases/metabolismo , Camundongos Transgênicos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , NF-kappa B/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Ubiquitina Tiolesterase/metabolismo
6.
Circ Res ; 131(9): 768-787, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36134578

RESUMO

RATIONALE: Vascular smooth muscle cells (VSMCs) phenotype switch from contractile to proliferative phenotype is a pathological hallmark in various cardiovascular diseases. Recently, a subset of long noncoding RNAs was identified to produce functional polypeptides. However, the functional impact and regulatory mechanisms of long noncoding RNAs in VSMCs phenotype switching remain to be fully elucidated. OBJECTIVES: To illustrate the biological function and mechanism of a VSMC-enriched long noncoding RNA and its encoded peptide in VSMC phenotype switching and vascular remodeling. RESULTS: We identified a VSMC-enriched transcript encoded by a previously uncharacterized gene, which we called phenotype switching regulator (PSR), which was markedly upregulated during vascular remodeling. Although PSR was annotated as a long noncoding RNA, we demonstrated that the lncPSR (PSR transcript) also encoded a protein, which we named arteridin. In VSMCs, both arteridin and lncPSR were necessary and sufficient to induce phenotype switching. Mechanistically, arteridin and lncPSR regulate downstream genes by directly interacting with a transcription factor YBX1 (Y-box binding protein 1) and modulating its nuclear translocation and chromatin targeting. Intriguingly, the PSR transcription was also robustly induced by arteridin. More importantly, the loss of PSR gene or arteridin protein significantly attenuated the vascular remodeling induced by carotid arterial injury. In addition, VSMC-specific inhibition of lncPSR using adeno-associated virus attenuated Ang II (angiotensin II)-induced hypertensive vascular remodeling. CONCLUSIONS: PSR is a VSMC-enriched gene, and its transcript IncPSR and encoded protein (arteridin) coordinately regulate transcriptional reprogramming through a shared interacting partner, YBX1. This is a previously uncharacterized regulatory circuit in VSMC phenotype switching during vascular remodeling, with lncPSR/arteridin as potential therapeutic targets for the treatment of VSMC phenotype switching-related vascular remodeling.


Assuntos
RNA Longo não Codificante , Angiotensina II/metabolismo , Proliferação de Células/genética , Células Cultivadas , Cromatina/metabolismo , Humanos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Fenótipo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Fatores de Transcrição/metabolismo , Remodelação Vascular
7.
Zhongguo Zhong Yao Za Zhi ; 48(1): 234-246, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-36725276

RESUMO

This study aimed to evaluate the efficacy and safety of Chinese patent medicines containing Hirudo in the treatment of atherosclerosis(AS) by network Meta-analysis, and to provide evidence-based reference for clinical treatment of AS. The clinical randomized controlled trial(RCT) on the treatment of atherosclerosis with Chinese patent medicines containing Hirudo were searched in CNKI, Wanfang, VIP, SinoMed, PubMed and EMbase from the establishment of the databases to July 1, 2022. And data extraction and quality assessment of the included RCT was performed according to the Cochrane standards. Stata 17 and ADDIS 1.16.5 were then used for Bayesian model network Meta-analysis. Finally, 67 RCTs with a total sample size of 6 826 cases were included, 3 569 cases in the experimental group and 3 257 cases in the control group, involving three oral Chinese patent medicines. Network Meta-analysis showed that in terms of reducing intima-media thickness(IMT), the top three Chinese patent medicines were Tongxinluo Capsules+sta-tins>Maixuekang Capsules+statins>Maixuekang Capsules. In terms of reducing plaque area, the top one was Maixuekang Capsules+sta-tins, and the other Chinese patent medicines had similar efficacy. For lowering AS Crouse scores, the top three were Maixuekang Capsules>Tongxinluo Capsules+statins>Naoxintong Capsules. For decreasing plaque number, the top three were Naoxintong Capsules+sta-tins>Tongxinluo Capsules+statins>Tongxinluo Capsules. With regard to adverse reactions/events, Naoxintong Capsules+statins had the lo-west incidence. In conclusion, in Chinese patent medicines containing Hirudo for the treatment of AS, Tongxinluo Capsules+statins, Maixuekang Capsules, Maixuekang Capsules+statins, and Naoxintong Capsules+statins were the primary choices to reduce IMT, AS Crouse scores, plaque area, and plaque number, respectively. The efficacy of Chinese patent medicines containing Hirudo with or without statins was more significant than that of statins alone in the four outcome indexes. Additionally, the treatment of AS should be evaluated comprehensively, and attention should be paid to Chinese patent medicines or their combination with western medicine, to optimize the treatment effect and minimize adverse reactions as the benchmark.


Assuntos
Aterosclerose , Medicamentos de Ervas Chinesas , Inibidores de Hidroximetilglutaril-CoA Redutases , Humanos , Metanálise em Rede , Medicamentos sem Prescrição/uso terapêutico , Cápsulas , Teorema de Bayes , Espessura Intima-Media Carotídea , Medicamentos de Ervas Chinesas/uso terapêutico , Aterosclerose/tratamento farmacológico , Medicina Tradicional Chinesa
8.
Circ Res ; 126(4): 517-529, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-31815603

RESUMO

RATIONALE: The gene encoding TCF21 (transcription factor 21) has been linked to coronary artery disease risk by human genome-wide association studies in multiple racial ethnic groups. In murine models, Tcf21 is required for phenotypic modulation of smooth muscle cells (SMCs) in atherosclerotic tissues and promotes a fibroblast phenotype in these cells. In humans, TCF21 expression inhibits risk for coronary artery disease. The molecular mechanism by which TCF21 regulates SMC phenotype is not known. OBJECTIVE: To better understand how TCF21 affects the SMC phenotype, we sought to investigate the possible mechanisms by which it regulates the lineage determining MYOCD (myocardin)-SRF (serum response factor) pathway. METHODS AND RESULTS: Modulation of TCF21 expression in human coronary artery SMC revealed that TCF21 suppresses a broad range of SMC markers, as well as key SMC transcription factors MYOCD and SRF, at the RNA and protein level. We conducted chromatin immunoprecipitation-sequencing to map SRF-binding sites in human coronary artery SMC, showing that binding is colocalized in the genome with TCF21, including at a novel enhancer in the SRF gene, and at the MYOCD gene promoter. In vitro genome editing indicated that the SRF enhancer CArG box regulates transcription of the SRF gene, and mutation of this conserved motif in the orthologous mouse SRF enhancer revealed decreased SRF expression in aorta and heart tissues. Direct TCF21 binding and transcriptional inhibition at colocalized sites were established by reporter gene transfection assays. Chromatin immunoprecipitation and protein coimmunoprecipitation studies provided evidence that TCF21 blocks MYOCD and SRF association by direct TCF21-MYOCD interaction. CONCLUSIONS: These data indicate that TCF21 antagonizes the MYOCD-SRF pathway through multiple mechanisms, further establishing a role for this coronary artery disease-associated gene in fundamental SMC processes and indicating the importance of smooth muscle response to vascular stress and phenotypic modulation of this cell type in coronary artery disease risk.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular/genética , Doença da Artéria Coronariana/genética , Predisposição Genética para Doença/genética , Proteínas Nucleares/genética , Fator de Resposta Sérica/genética , Transativadores/genética , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sítios de Ligação/genética , Células Cultivadas , Regulação da Expressão Gênica , Células HEK293 , Humanos , Miócitos de Músculo Liso/citologia , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas/genética , Ligação Proteica , Fator de Resposta Sérica/metabolismo , Transdução de Sinais/genética , Transativadores/metabolismo
9.
Crit Care ; 26(1): 295, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36171582

RESUMO

BACKGROUND: The combination therapy of hydrocortisone, vitamin C, and thiamine has been proposed as a potential treatment in patients with sepsis and septic shock. However, subsequent trials have reported conflicting results in relation to survival outcomes. Hence, we performed this randomized controlled trial (RCT) to evaluate the efficacy and safety of early combination therapy among adult patients with septic shock. METHODS: This single-center, double-blind RCT enrolled adult patients with diagnosis of septic shock within 12 h from Northern Jiangsu People's Hospital between February 2019 and June 2021. Recruited patients were randomized 1:1 to receive intervention (hydrocortisone 200 mg daily, vitamin C 2 g every 6 h, and thiamine 200 mg every 12 h) or placebo (0.9% saline) for 5 days or until ICU discharge. The primary endpoint was 90-day mortality. The secondary endpoints included mortality at day 28, ICU discharge, and hospital discharge; shock reversal; 72-h Delta SOFA score; ICU-free days, vasopressor-free days, and ventilator support -free days up to day 28; ICU length of stay (LOS) and hospital LOS. RESULTS: Among 426 patients randomized, a total of 408 patients with septic shock were included in the per-protocol (PP) analysis, of which 203 were assigned to the intervention group and 205 to the placebo group. In the PP population, the primary outcome of 90-day mortality was 39.9% (81/203) and 39.0% (80/205) in the intervention and the placebo groups, respectively, and was not significantly different (P = 0.86). There was no significant difference between two groups in 28-day mortality (36.5% vs. 36.1%, P = 0.94) or the ICU mortality (31.5% vs. 28.8%, P = 0.55) and hospital mortality (34.5% vs. 33.2%, P = 0.78). No other secondary outcomes showed significant differences between two groups, including shock reversal, vasopressor-free days, and ICU LOS. Intention-to-treat analysis included all the 426 patients and confirmed these results (all P > 0.05). CONCLUSION: Among adult patients with septic shock, early use of hydrocortisone, vitamin C, and thiamine combination therapy compared with placebo did not confer survival benefits. Trial registration ClinicalTrials.gov: NCT03872011 , registration date: March 12, 2019.


Assuntos
Choque Séptico , Adulto , Ácido Ascórbico/farmacologia , Ácido Ascórbico/uso terapêutico , Quimioterapia Combinada , Humanos , Hidrocortisona , Solução Salina/uso terapêutico , Tiamina/farmacologia , Tiamina/uso terapêutico , Vasoconstritores/uso terapêutico , Vitaminas/uso terapêutico
10.
Proc Natl Acad Sci U S A ; 116(2): 546-555, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30584103

RESUMO

SENCR is a human-specific, vascular cell-enriched long-noncoding RNA (lncRNA) that regulates vascular smooth muscle cell and endothelial cell (EC) phenotypes. The underlying mechanisms of action of SENCR in these and other cell types is unknown. Here, levels of SENCR RNA are shown to be elevated in several differentiated human EC lineages subjected to laminar shear stress. Increases in SENCR RNA are also observed in the laminar shear stress region of the adult aorta of humanized SENCR-expressing mice, but not in disturbed shear stress regions. SENCR loss-of-function studies disclose perturbations in EC membrane integrity resulting in increased EC permeability. Biotinylated RNA pull-down and mass spectrometry establish an abundant SENCR-binding protein, cytoskeletal-associated protein 4 (CKAP4); this ribonucleoprotein complex was further confirmed in an RNA immunoprecipitation experiment using an antibody to CKAP4. Structure-function studies demonstrate a noncanonical RNA-binding domain in CKAP4 that binds SENCR Upon SENCR knockdown, increasing levels of CKAP4 protein are detected in the EC surface fraction. Furthermore, an interaction between CKAP4 and CDH5 is enhanced in SENCR-depleted EC. This heightened association appears to destabilize the CDH5/CTNND1 complex and augment CDH5 internalization, resulting in impaired adherens junctions. These findings support SENCR as a flow-responsive lncRNA that promotes EC adherens junction integrity through physical association with CKAP4, thereby stabilizing cell membrane-bound CDH5.


Assuntos
Junções Aderentes/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Proteínas de Membrana/metabolismo , RNA Longo não Codificante/metabolismo , Junções Aderentes/genética , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/genética , Caderinas/metabolismo , Cateninas/genética , Cateninas/metabolismo , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Proteínas de Membrana/genética , Domínios Proteicos , RNA Longo não Codificante/genética , Resistência ao Cisalhamento/fisiologia , delta Catenina
11.
J Xray Sci Technol ; 30(3): 433-445, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342075

RESUMO

Cardiac CT provides critical information for the evaluation of cardiovascular diseases. However, involuntary patient motion and physiological movement of the organs during CT scanning cause motion blur in the reconstructed CT images, degrading both cardiac CT image quality and its diagnostic value. In this paper, we propose and demonstrate an effective and efficient method for CT coronary angiography image quality grading via semi-automatic labeling and vessel tracking. These algorithms produce scores that accord with those of expert readers to within 0.85 points on a 5-point scale. We also train a neural network model to perform fully-automatic motion artifact grading. We demonstrate, using XCAT simulation tools to generate realistic phantom CT data, that supplementing clinical data with synthetic data improves the scoring performance of this network. With respect to ground truth scores assigned by expert operators, the mean square error of grading motion of the right coronary artery is reduced by 36% by synthetic data supplementation. This demonstrates that augmentation of clinical training data with realistically synthesized images can potentially reduce the number of clinical studies needed to train the network.


Assuntos
Artefatos , Tomografia Computadorizada por Raios X , Algoritmos , Angiografia por Tomografia Computadorizada/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Movimento (Física) , Imagens de Fantasmas , Tomografia Computadorizada por Raios X/métodos
12.
J Intensive Care Med ; 35(10): 971-983, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30270720

RESUMO

BACKGROUND: The efficacy of low-dose hydrocortisone therapy in the management of septic shock remains controversial in critical care for many years. Hence, we performed this meta-analysis of randomized controlled trials (RCTs) with trial sequential analysis (TSA) to evaluate its effect on clinical outcome among adult patients with septic shock. METHODS: We identified relevant RCTs published from inception to March 7, 2018 comparing low-dose hydrocortisone with placebo or no intervention in adults admitted to the intensive care unit (ICU) for septic shock. Meta-analyses were performed for the primary and secondary outcomes. The risk of bias was assessed using the Cochrane Collaboration's instrument. Trial sequential analysis was used to pool the results from the included studies for the primary outcomes. RESULTS: Thirteen studies were retrieved by our literature search strategy. There were no significant differences in 28-day mortality (odds ratio [OR] = 0.90, 95% confidence interval [CI] = 0.81-1.00; P = .05) and hospital mortality (OR = 0.91, 95% CI = 0.82-1.02; P = .09) between the 2 groups, which were confirmed by TSA. However, there was a significant improvement in shock reversal in the hydrocortisone group (OR = 1.33, 95% CI = 1.02-1.72; P = .03). Furthermore, subgroup analyses revealed that hydrocortisone plus fludrocortisone statistically reduced the rate of 28-day mortality (OR = 0.79, 95% CI = 0.64-0.97; P = .03), ICU mortality (OR = 0.77, 95% CI = 0.63-0.95; P = .02), and hospital mortality (OR = 0.77, 95% CI = 0.63-0.95; P = .01) in comparison with the placebo, the results were also confirmed by TSA. CONCLUSION: Among adult patients with septic shock, the use of low-dose hydrocortisone compared with control did not confer overall survival benefits, albeit improving shock reversal rate. The benefit of reducing 28-day mortality, ICU mortality, and hospital mortality was observed in combination use of hydrocortisone and fludrocortisone.


Assuntos
Anti-Inflamatórios/administração & dosagem , Cuidados Críticos/métodos , Hidrocortisona/administração & dosagem , Choque Séptico/tratamento farmacológico , Choque Séptico/mortalidade , Adulto , Idoso , Resultados de Cuidados Críticos , Feminino , Mortalidade Hospitalar , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Razão de Chances , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Resultado do Tratamento
13.
Proc Natl Acad Sci U S A ; 114(13): E2739-E2747, 2017 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-28292896

RESUMO

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a congenital visceral myopathy characterized by severe dilation of the urinary bladder and defective intestinal motility. The genetic basis of MMIHS has been ascribed to spontaneous and autosomal dominant mutations in actin gamma 2 (ACTG2), a smooth muscle contractile gene. However, evidence suggesting a recessive origin of the disease also exists. Using combined homozygosity mapping and whole exome sequencing, a genetically isolated family was found to carry a premature termination codon in Leiomodin1 (LMOD1), a gene preferentially expressed in vascular and visceral smooth muscle cells. Parents heterozygous for the mutation exhibited no abnormalities, but a child homozygous for the premature termination codon displayed symptoms consistent with MMIHS. We used CRISPR-Cas9 (CRISPR-associated protein) genome editing of Lmod1 to generate a similar premature termination codon. Mice homozygous for the mutation showed loss of LMOD1 protein and pathology consistent with MMIHS, including late gestation expansion of the bladder, hydronephrosis, and rapid demise after parturition. Loss of LMOD1 resulted in a reduction of filamentous actin, elongated cytoskeletal dense bodies, and impaired intestinal smooth muscle contractility. These results define LMOD1 as a disease gene for MMIHS and suggest its role in establishing normal smooth muscle cytoskeletal-contractile coupling.


Assuntos
Anormalidades Múltiplas/genética , Autoantígenos/fisiologia , Colo/anormalidades , Proteínas do Citoesqueleto/fisiologia , Pseudo-Obstrução Intestinal/genética , Proteínas Musculares/fisiologia , Bexiga Urinária/anormalidades , Animais , Autoantígenos/genética , Autoantígenos/metabolismo , Códon sem Sentido , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Feminino , Humanos , Recém-Nascido , Camundongos , Contração Muscular/genética , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Liso/fisiologia
14.
Arterioscler Thromb Vasc Biol ; 38(9): 2184-2190, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29976770

RESUMO

Objective- Unreliable antibodies often hinder the accurate detection of an endogenous protein, and this is particularly true for the cardiac and smooth muscle cofactor, MYOCD (myocardin). Accordingly, the mouse Myocd locus was targeted with 2 independent epitope tags for the unambiguous expression, localization, and activity of MYOCD protein. Approach and Results- 3cCRISPR (3-component clustered regularly interspaced short palindromic repeat) was used to engineer a carboxyl-terminal 3×FLAG or 3×HA epitope tag in mouse embryos. Western blotting with antibodies to each tag revealed a MYOCD protein product of ≈150 kDa, a size considerably larger than that reported in virtually all publications. MYOCD protein was most abundant in some adult smooth muscle-containing tissues with surprisingly low-level expression in the heart. Both alleles of Myocd are active in aorta because a 2-fold increase in protein was seen in mice homozygous versus heterozygous for FLAG-tagged Myocd. ChIP (chromatin immunoprecipitation)-quantitative polymerase chain reaction studies provide proof-of-principle data demonstrating the utility of this mouse line in conducting genome-wide ChIP-seq studies to ascertain the full complement of MYOCD-dependent target genes in vivo. Although FLAG-tagged MYOCD protein was undetectable in sections of adult mouse tissues, low-passaged vascular smooth muscle cells exhibited expected nuclear localization. Conclusions- This report validates new mouse models for analyzing MYOCD protein expression, localization, and binding activity in vivo and highlights the need for rigorous authentication of antibodies in biomedical research.


Assuntos
Sistemas CRISPR-Cas , Mapeamento de Epitopos/métodos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteínas Nucleares/análise , Proteínas Nucleares/metabolismo , Transativadores/análise , Transativadores/metabolismo , Animais , Embrião de Mamíferos , Epitopos/análise , Camundongos , Músculo Liso Vascular/química , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/química
15.
J Am Soc Nephrol ; 29(2): 416-422, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29114040

RESUMO

Podocytes contain an intricate actin cytoskeleton that is essential for the specialized function of this cell type in renal filtration. Serum response factor (SRF) is a master transcription factor for the actin cytoskeleton, but the in vivo expression and function of SRF in podocytes are unknown. We found that SRF protein colocalizes with podocyte markers in human and mouse kidneys. Compared with littermate controls, mice in which the Srf gene was conditionally inactivated with NPHS2-Cre exhibited early postnatal proteinuria, hypoalbuminemia, and azotemia. Histologic changes in the mutant mice included glomerular capillary dilation and mild glomerulosclerosis, with reduced expression of multiple canonical podocyte markers. We also noted tubular dilation, cell proliferation, and protein casts as well as reactive changes in mesangial cells and interstitial inflammation. Ultrastructure analysis disclosed foot process effacement with loss of slit diaphragms. To ascertain the importance of SRF cofactors in podocyte function, we disabled the myocardin-related transcription factor A and B genes. Although loss of either SRF cofactor alone had no observable effect in the kidney, deficiency of both recapitulated the Srf-null phenotype. These results establish a vital role for SRF and two SRF cofactors in the maintenance of podocyte structure and function.


Assuntos
Actinas/metabolismo , Podócitos/metabolismo , Podócitos/ultraestrutura , Fator de Resposta Sérica/fisiologia , Transativadores/genética , Fatores de Transcrição/genética , Actinina/genética , Actinas/genética , Animais , Citoesqueleto , Dilatação Patológica/genética , Feminino , Humanos , Túbulos Renais Distais/patologia , Túbulos Renais Proximais/patologia , Masculino , Camundongos , Camundongos Knockout , Podócitos/fisiologia , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Proteínas Repressoras/genética , Fator de Resposta Sérica/genética , Proteínas WT1
16.
Fish Shellfish Immunol ; 55: 367-73, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27298271

RESUMO

Natucin C (NC) and Natucin P (NP) are two kinds of antimicrobial peptides (AMPs). In the present study, the effects of NC-NP mixture on a tilapia species (Oreochromis niloticus) were examined. Animals were fed with either a control diet or one of five AMP-supplemented diets for eight weeks. AMP-supplemented diets contained five increasing levels of NP from G1 to G5 and one level of NC (200 mg/kg). Results showed that fish in the G3, G4 and G5 groups had significantly higher levels of total protein (TP), albumin (ALB) and globulin (GLO) in serum than fish in the control group. Fish fed with G4 and G5 diets exhibited significantly higher high-density lipoprotein cholesterol (HDL-C) levels compared to the control fish. Lipopolysaccharide (LPS) levels in all AMP-supplemented groups were significantly lower than the control. In addition, the total antioxidant capacity (TAOC) and lysozyme (LZM) activities were significantly increased in fish fed with the G3 and G4 diets, respectively compared to the control. The serum malondialdehyde (MDA) levels in fish fed with AMP-supplemented diets were significantly decreased compared to those not supplemented with AMPs. Furthermore, the mRNA expressions of tumor necrosis factor alpha (TNF-α), interleukin-1-beta (IL-1ß), gamma interferon (IFN-γ) and heat shock protein 70 (HSP70) in the hepatopancreas, spleen, kidney and gill were measured. Overall, the expression levels were enhanced in an NP dose-dependent and tissue-specific manner. The expressions of four genes in four organs (except IL-1ß in spleen, and TNF-α and HSP70 in gill) were significantly upregulated in fish fed with the G5 diet. Fish fed with the G4 diet had increased expression levels of IL-1ß in spleen and IFN-γ in kidney. The relative expression levels of TNF-α, IL-1ß and HSP70 in the hepatopancreas in fish fed with the G3 diet were significantly upregulated compared to the control. Transcriptional levels of IL-1ß and HSP70 in the hepatopancreas, IFN-γ and HSP70 in the kidney and IL-1ß in the gills of fish fed with the G2 diet were upregulated. Taken together, our results indicated that the NC-NP mixture can enhance the antioxidant capacity and innate immune ability of O. niloticus, indicating that this mixture might be a potential alternative to antibiotics when used as a feed additive.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Antioxidantes/metabolismo , Ciclídeos , Imunidade Inata/efeitos dos fármacos , Ração Animal/análise , Animais , Análise Química do Sangue/veterinária , Ciclídeos/sangue , Ciclídeos/imunologia , Dieta/veterinária
17.
Artif Organs ; 40(1): 94-100, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25981202

RESUMO

Retinal prostheses have the potential to restore partial vision. Object recognition in scenes of daily life is one of the essential tasks for implant wearers. Still limited by the low-resolution visual percepts provided by retinal prostheses, it is important to investigate and apply image processing methods to convey more useful visual information to the wearers. We proposed two image processing strategies based on Itti's visual saliency map, region of interest (ROI) extraction, and image segmentation. Itti's saliency model generated a saliency map from the original image, in which salient regions were grouped into ROI by the fuzzy c-means clustering. Then Grabcut generated a proto-object from the ROI labeled image which was recombined with background and enhanced in two ways--8-4 separated pixelization (8-4 SP) and background edge extraction (BEE). Results showed that both 8-4 SP and BEE had significantly higher recognition accuracy in comparison with direct pixelization (DP). Each saliency-based image processing strategy was subject to the performance of image segmentation. Under good and perfect segmentation conditions, BEE and 8-4 SP obtained noticeably higher recognition accuracy than DP, and under bad segmentation condition, only BEE boosted the performance. The application of saliency-based image processing strategies was verified to be beneficial to object recognition in daily scenes under simulated prosthetic vision. They are hoped to help the development of the image processing module for future retinal prostheses, and thus provide more benefit for the patients.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Reconhecimento Psicológico , Percepção Visual , Próteses Visuais , Pessoas com Deficiência Visual/reabilitação , Adulto , Algoritmos , Feminino , Lógica Fuzzy , Humanos , Masculino , Estimulação Luminosa , Desenho de Prótese , Pessoas com Deficiência Visual/psicologia , Adulto Jovem
18.
Biochem Biophys Res Commun ; 462(1): 38-45, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-25935480

RESUMO

Autophagy is evolutionarily conservative in eukaryotic cells that engulf cellular long-lived proteins and organelles, and it degrades the contents through fusion with lysosomes, via which the cell acquires recycled building blocks for the synthesis of new molecules. In this study, we revealed that peiminine induces cell death and enhances autophagic flux in colorectal carcinoma HCT-116 cells. We determined that peiminine enhances the autophagic flux by repressing the phosphorylation of mTOR through inhibiting upstream signals. Knocking down ATG5 greatly reduced the peiminine-induced cell death in wild-type HCT-116 cells, while treating Bax/Bak-deficient cells with peiminine resulted in significant cell death. In summary, our discoveries demonstrated that peiminine represses colorectal carcinoma cell proliferation and cell growth by inducing autophagic cell death.


Assuntos
Autofagia/efeitos dos fármacos , Produtos Biológicos/farmacologia , Cevanas/farmacologia , Neoplasias Colorretais/prevenção & controle , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Produtos Biológicos/química , Cevanas/química , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Feminino , Células HCT116 , Células HeLa , Humanos , Immunoblotting , Imuno-Histoquímica , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia Confocal , Estrutura Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Biochem Biophys Res Commun ; 457(1): 37-42, 2015 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25529446

RESUMO

Previous studies showed that miR-378a plays important roles in adipogenesis and obesity; however, the precise mechanisms of action remain unknown. Here, we found that miR-378a-3p expression is up-regulated in adipose tissues of high fat diet-induced obese mice, as well as during the differentiation of 3T3-L1 preadipocytes. Mir-378a-3p induced adipogenesis by targeting mitogen-activated protein kinase 1 (MAPK1). Overexpression of miR-378a-3p or silencing MAPK1 reduced MAPK1 expression and enhanced adipogenesis, whereas blockage of endogenous miR-378a-3p had the opposite effect, suggesting that miR-378a-3p promotes the adipogenesis of 3T3-L1 cells by targeting MAPK1.


Assuntos
Adipogenia , MicroRNAs/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Células 3T3-L1 , Adipogenia/genética , Animais , Sequência de Bases , Dieta Hiperlipídica , Masculino , Camundongos , MicroRNAs/genética , Modelos Biológicos , Dados de Sequência Molecular , Obesidade/genética , Obesidade/patologia , Regulação para Cima/genética
20.
J Neuroeng Rehabil ; 12: 73, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26311232

RESUMO

BACKGROUND: Epiretinal prostheses have been greatly successful in helping restore the vision of patients blinded by retinal degenerative diseases. The design of stimulating electrodes plays a crucial role in the performance of epiretinal prostheses. The objective of this study was to investigate, through computational modeling analysis, the effects on the excitation of retinal ganglion cells (RGCs) when different three-dimensional (3-D) electrodes were placed in the epiretinal space. METHODS: 3-D finite element models of retinal electrical stimulation were created in COMSOL using a platinum microelectrode, a vitreous body, multi-layered retinal tissue, and retinal pigment epithelium (RPE). Disk and non-planar electrodes with different 3-D structures were used in the epiretinal electrical stimulation. In addition, a multi-RGC model including ionic mechanisms was constructed in NEURON to study the excitability of RGCs in response to epiretinal electrical stimulation by different types of electrodes. Threshold current, threshold charge density, and the activated RGC area were the three key factors used to evaluate the stimulating electrode's performance. RESULTS: As the electrode-retina distance increased, both threshold current and threshold charge density showed an approximately linear relationship. Increasing the disk electrode's diameter resulted in an increase in threshold current and a decrease in threshold charge density. Non-planar electrodes evoked different activation responses in RGCs than the disk electrode. Concave electrodes produced superior stimulation localization and electrode safety while convex electrodes performed relatively poorly. CONCLUSIONS: Investigation of epiretinal electrical stimulation using different 3-D electrodes would further the optimization of electrode design and help improve the performance of epiretinal prostheses. The combination of finite element analysis in COMSOL and NEURON software provides an efficient way to evaluate the influences of various 3-D electrodes on epiretinal electrical stimulation. Non-planar electrodes had larger threshold currents than disk electrodes. Of the five types of electrodes, concave hemispherical electrodes may be the ideal option, considering their superior stimulation localization and electrode safety.


Assuntos
Terapia por Estimulação Elétrica/instrumentação , Terapia por Estimulação Elétrica/métodos , Eletrodos , Retina , Algoritmos , Simulação por Computador , Terapia por Estimulação Elétrica/efeitos adversos , Eletrodos/efeitos adversos , Análise de Elementos Finitos , Humanos , Potenciais da Membrana , Modelos Neurológicos , Modelos Teóricos , Próteses Neurais , Desenho de Prótese , Retina/anatomia & histologia , Células Ganglionares da Retina/fisiologia
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