Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Front Microbiol ; 15: 1402235, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974026

RESUMO

Introduction: The H9N2 subtype is a predominant avian influenza virus (AIV) circulating in Chinese poultry, forming various genotypes (A-W) based on gene segment origins. This study aims to investigate the genotypic distribution and pathogenic characteristics of H9N2 isolates from wild birds and domestic poultry in Yunnan Province, China. Methods: Eleven H9N2 strains were isolated from fecal samples of overwintering wild birds and proximate domestic poultry in Yunnan, including four from common cranes (Grus grus), two from bar-headed geese (Anser indicus), and five from domestic poultry (Gallus gallus). Phylogenetic analysis was conducted to determine the genotypes, and representative strains were inoculated into Yunnan mallard ducks to assess pathogenicity. Results: Phylogenetic analysis revealed that five isolates from domestic birds and one from a bar-headed goose belong to genotype S, while the remaining five isolates from wild birds belong to genotype A. These bird-derived strains possess deletions in the stalk domain of NA protein and the N166D mutation of HA protein, typical of poultry strains. Genotype S H9N2 demonstrated oropharyngeal shedding, while genotype A H9N2 exhibited cloacal shedding and high viral loads in the duodenum. Both strains caused significant pathological injuries, with genotype S inducing more severe damage to the thymus and spleen, while genotype A caused duodenal muscle layer rupture. Discussion: These findings suggest that at least two genotypes of H9N2 are currently circulating in Yunnan, and Yunnan mallard ducks potentially act as intermediaries in interspecies transmission. These insights highlight the importance of analyzing the current epidemiological transmission characteristics of H9N2 among wild and domestic birds in China.

2.
Mol Cancer Ther ; 22(12): 1479-1492, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37710057

RESUMO

Aberrant activation of the FGF19-FGFR4 signaling pathway plays an essential role in the tumorigenesis of hepatocellular carcinoma (HCC). As such, FGFR4 inhibition has emerged as a novel therapeutic option for the treatment of HCC and has shown preliminary efficacy in recent clinical trials for patients exhibiting aberrant FGF19 expression. Resistance to kinase inhibitors is common in oncology, presenting a major challenge in the clinical treatment process. Hence, we investigated the potential mechanisms mediating and causing resistance to FGFR4 inhibition in HCC. Upon the successful establishment of a battery of cellular models developing resistance to FGFR4 inhibitors, we have identified the activation of EGFR, MAPK, and AKT signaling as the primary mechanisms mediating the acquired resistance. Combination of inhibitors against EGFR or its downstream components restored sensitivity to FGFR4 inhibitors. In parental HCC cell lines, EGF treatment also resulted in resistance to FGFR4 inhibitors. This resistance was effectively reverted by inhibitors of the EGFR signaling pathway, suggesting that EGFR activation is a potential cause of intrinsic resistance. We further confirmed the above findings in vivo in mouse xenograft tumor models. Genomic analysis of patient samples from The Cancer Genome Atlas confirmed that a segment of patients with HCC harboring FGF19 overexpression indeed exhibited increased activation of EGFR signaling. These findings conclusively indicate that both induced and innate activation of EGFR could mediate resistance to FGFR4 inhibition, suggesting that dual blockade of EGFR and FGFR4 may be a promising future therapeutic strategy for the treatment of FGF19-FGFR4 altered HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Transdução de Sinais , Receptores ErbB/metabolismo , Linhagem Celular Tumoral , Receptor Tipo 4 de Fator de Crescimento de Fibroblastos/genética
3.
Viruses ; 15(8)2023 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-37631996

RESUMO

Fowl adenoviruses (FAdVs) are distributed worldwide in poultry and incriminated as the etiological agents for several health problems in fowls, and are capable of crossing species barriers between domestic and wild fowls. An FAdV strain was, for the first time, isolated from black-necked crane in this study, and was designated as serotype 4 Fowl aviadenovirus C (abbreviated as BNC2021) according to the phylogenetic analysis of its DNA polymerase and hexon gene. The viral genomic sequence analysis demonstrated that the isolate possessed the ORF deletions that are present in FAdV4 strains circulating in poultry fowls in China and the amino acid mutations associated with viral pathogenicity in the hexon and fiber 2 proteins. A viral challenge experiment with mallard ducks demonstrated systemic viral infection and horizontal transmission. BNC2021 induced the typical clinical signs of hepatitis-hydropericardium syndrome (HHS) with swelling and inflammation in multiple organs and showed significant viral replication in all eight organs tested in the virus-inoculated ducks and their contactees at 6 dpi. The findings highlight the importance of surveillance of FAdVs in wild birds.


Assuntos
Aviadenovirus , Sepse , Animais , Filogenia , Sorogrupo , Genômica , Aves , Patos , Hexametônio
4.
Environ Sci Pollut Res Int ; 30(45): 100675-100700, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37639095

RESUMO

This study attempts to explore the essential influencing factors of landslides and explores the effects of different datasets on landslide susceptibility mapping (LSM) at six grid resolutions (i.e., 10 m, 30 m, 300 m, 1000 m, 2000 m, and 3000 m). Firstly, the geospatial dataset of 21 influencing factors was extracted from 1847 historical landslide InSAR (Interferometric Synthetic Aperture Radar) points, which were taken as a sample for the Sino-Pakistani Karakorum Highway. Secondly, Spearman correlation coefficient (SCC), random forest feature selection (RFFS), and their combinations (SCC-RFFS) were selected at different grid resolutions to identify the essential influencing factors from the 21 original factors. A random division into training set (70%) and test set (30%) was performed. Then, the LSM models for the original influencing factors and the selected influencing factors were constructed separately using machine learning models. Finally, the reasonableness of the essential influencing factors was verified by comparing the accuracy of the models under different grid resolutions. The results show that (1) relief degree of land surface (RDLS), SPI, and rainfall have significant effects on landslide occurrence. (2) The primary elements (i.e., RDLS, slop, rainfall) are less affected by the grid resolution, while the secondary elements (TWI) are more affected by the grid resolution. (3) At 30 m, the SCC-RFFS-RF model can get the highest landslide susceptibility model accuracy. The prediction will also provide scientific guidance for the allocation of land resources on a regional and global scale, and minimize the human and economic costs along the highway, while ensuring safe highway operations.


Assuntos
Deslizamentos de Terra , Humanos , Aprendizado de Máquina , Algoritmo Florestas Aleatórias
6.
Aging (Albany NY) ; 14(7): 3143-3154, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35381577

RESUMO

Inflammatory cytokines contribute to the development of osteoporosis with sophisticated mechanisms. Globally alteration of long-chain non-coding RNA was screened in osteoporosis, while we still know little about their functional role in the inflammatory cytokine secretion. In this study, we collected the peripheral blood mononuclear cells (PBMCs) from post-menopausal osteoporosis patients to measure lncRNA MIAT (lncMIAT) expression levels, and explored the molecular mechanism of lncMIAT induced inflammatory cytokine secretion. We identified increased lncMIAT expression in the PBMCs of post-menopausal osteoporosis patients, which was an important predictive biomarker for the diagnosis. LncMIAT expression in PBMCs was positively correlated with the inflammatory cytokine secretion. Mechanism study indicated that lncMIAT increased the expression levels of p38MAPK by crosstalk with miR-216a in PBMCs. The lncMIAT/miR-216a/p38MAPK signaling contributed predominantly to the increased inflammatory cytokine secretion in the PBMCs from postmenopausal osteoporosis. In conclusion, we identified that increased lncMIAT in PBMCs induced inflammatory cytokine secretion, which contributed to the development of post-menopausal osteoporosis. lncMIAT/miR-216a axis was critical for the regulation of AMPK/p38MAPK signaling, which may be a promising therapeutic target for osteoporosis treatment by inflammatory cytokine inhibition.


Assuntos
MicroRNAs , Osteoporose Pós-Menopausa , RNA Longo não Codificante , Citocinas , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoporose Pós-Menopausa/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
7.
Ann Palliat Med ; 10(11): 11524-11528, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34872277

RESUMO

BACKGROUND: Understanding the relationship between the greater trochanter, the lesser trochanter, and the femoral head center is helpful to achieve satisfactory lower limb length in hip arthroplasty, and it may be more important when the contralateral side of the surgical hip cannot be referenced. This work aims to measure the relative position of the femoral head center, the greater trochanter, and the lesser trochanter, and analyze the relationship between these anatomical landmarks. METHODS: The femoral head diameter (D), the linear distance (G) from the femoral head center (C) to the greater trochanter, and the linear distance (L) from the femoral head center to the lesser trochanter were measured by pelvic X-ray. The basic information of the data was analyzed, the ratios of G to D and L to D were calculated, the functional relationship between the data was analyzed after the factors of gender and age were included, and the 95% reference intervals of the basic data and ratio data were calculated. RESULTS: A total of 97 patients with 194 hips were enrolled in this study. The diameter D was 5.08±0.43 cm, the distance G was 4.68±0.45 cm, and the distance L was 4.28±0.49 cm. The G/D ratio was 0.92±0.07, and the 95% reference range was 0.78-1.06. The L/D ratio was 0.84±0.08, and the 95% reference range was 0.68-1.00. Gender (g) was included in the regression analysis, and the regression equations G =1.890+0.536*D and L =1.129+0.620*D were obtained. Age was not related to the distances G and L. CONCLUSIONS: The basic data of G, D, and L was measured, and the relationship between these anatomical landmarks was analyzed.


Assuntos
Artroplastia de Quadril , Cabeça do Fêmur , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Cabeça do Fêmur/diagnóstico por imagem , Humanos , Radiografia , Valores de Referência
8.
Food Sci Nutr ; 7(7): 2374-2380, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31367366

RESUMO

This study aimed to isolate starch and evaluate its chemical and structural characteristics from six Chinese hulless barley (HB) cultivars. Starch isolated from naked barley displays A-type crystalline packing and a regular granular shape. We measured peak viscosity values ranging from 237 to 264 cP, trough viscosity values from 305 to 380 cP, breakdown values from 390 to 535 cP, final viscosities from 357 to 523 cP, setback values from 245 to 354 cP and 383 to 460 cP, peak times from 5.53 to 5.73 min, and pasting temperatures from 93.10 to 94.65°C by RVA. Transition temperatures (T 0, T p, and T c), gelatinization temperature ranges (ΔT r), and enthalpies of gelatinization (ΔH) were measured on a differential scanning calorimeter analyzer (DSC) and ranged from 57.81 to 61.25°C, 64.36 to 67.57°C, 82.03 to 84.70°C, and 21.52 to 26.89°C and 7.14 to 10.66 J/g, respectively. The varying chemical and structural characteristics of HB starch isolated from different cultivars suggested the potential for broader applications of the cereal.

9.
Theranostics ; 9(12): 3501-3514, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31281493

RESUMO

Identification of proper agents to increase or activate UCP1+ cells in adipose tissues remains a potent therapeutic strategy to combat obesity. Screening systems for UCP1 activators have been previously established and allow for unbiased discovery of effective compound(s). Methods: A previously established Ucp1-2A-GFP reporter system was applied to a chemical library containing 33 phosphatase inhibitors. Compounds that can significantly activate UCP1 expression were further tested in vivo in mouse adipose tissues. Possible underlying mechanism was explored via RNA profiling, CMAP analysis, CRISPR targeting as well as inhibitor treatments. Results: We identified BML-260, a known potent inhibitor of the dual-specific phosphatase JSP-1, that significantly increased UCP1 expression in both brown and white adipocytes. BML-260 treatment also activated oxidative phosphorylation genes, increased mitochondrial activity as well as heat generation in vitro and in vivo. Mechanistic studies revealed that effect of BML-260 on adipocytes was partly through activated CREB, STAT3 and PPAR signaling pathways, and was unexpectedly JSP-1 independent. Conclusion: The rhodanine derivate BML-260 was previously identified to be a JSP-1 inhibitor, and thus was proposed to treat inflammatory and proliferative disorders associated with dysfunctional JNK signaling. This work provides evidences that BML-260 can also exert a JSP-1-independent effect in activating UCP1 and thermogenesis in adipocytes, and be potentially applied to treat obesity.


Assuntos
Adipócitos/efeitos dos fármacos , Ativadores de Enzimas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Rodanina/análogos & derivados , Rodanina/metabolismo , Ativação Transcricional , Proteína Desacopladora 1/metabolismo , Adipócitos/enzimologia , Animais , Células Cultivadas , Ativadores de Enzimas/isolamento & purificação , Humanos , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Rodanina/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Termogênese/efeitos dos fármacos
10.
Cell Rep ; 26(4): 884-892.e4, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30673611

RESUMO

DNA variants in the SLC16A11 coding region were identified to be strongly associated with type 2 diabetes (T2DM) in a Mexican population. Previous studies suggested that these variants disrupt SLC16A11 function and therefore proposed to revive SLC16A11 levels or activity to achieve therapeutic benefit. However, with knockout mouse models, here we show that Slc16a11 depletion has no significant metabolic defects. Further studies demonstrate that reconstitution of the mutant, but not the wild-type Slc16a11, in the liver of knockout mice causes more triglyceride accumulation and induction of insulin resistance via upregulation of lipin 1, suggesting gaining of aberrant functions of the mutant protein that affects lipid metabolism. Our findings offer a different explanation to the function of these diabetic variants, challenging the concept of enhancing SLC16A11 function to treat T2DM. The contradictory results by our and previous studies suggest that how the SLC16A11 locus contributes to human metabolism warrants further investigation.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Mutação com Ganho de Função , Resistência à Insulina/genética , Transportadores de Ácidos Monocarboxílicos , Triglicerídeos , Animais , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Células HEK293 , Humanos , Camundongos , Camundongos Knockout , Transportadores de Ácidos Monocarboxílicos/genética , Transportadores de Ácidos Monocarboxílicos/metabolismo , Fosfatidato Fosfatase/genética , Fosfatidato Fosfatase/metabolismo , Triglicerídeos/genética , Triglicerídeos/metabolismo
11.
Oncotarget ; 8(19): 31612-31625, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28404942

RESUMO

Ascorbic acid, ß-glycerophosphate, and dexamethasone have been used in osteogenesis differentiation medium for in vitro cell culture, nothing is known for delivering these three bioactive compounds in vivo. In this study, we synthesized a novel bioactive scaffold by combining these three compounds with a lysine diisocyanate-based polyurethane. These bioactive compounds were released from the scaffold during the degradation process. The cell culture showed that the sponge-like structure in the scaffold was critical in providing a large surface area to support cell growth and all degradation products of the polymer were non-toxic. This bioactive scaffold enhanced the bone regeneration as evidenced by increasing the expression of three bone-related genes including collagen type I, Runx-2 and osteocalcin in rabbit bone marrow stem cells (BMSCs) in vitro and in vivo. The osteogenesis differentiation of BMSCs cultured in this bioactive scaffold was similar to that in osteogenesis differentiation medium and more extensive in this bioactive scaffold compared to the scaffold without these three bioactive compounds. These results indicated that the scaffold containing three bioactive compounds was a good osteogenesis differentiation promoter to enhance the osteogenesis differentiation and new bone formation in vivo.


Assuntos
Ácido Ascórbico/administração & dosagem , Regeneração Óssea , Dexametasona/administração & dosagem , Glicerofosfatos/administração & dosagem , Osteogênese/efeitos dos fármacos , Alicerces Teciduais , Animais , Materiais Biocompatíveis , Diferenciação Celular , Células Cultivadas , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Polímeros , Coelhos , Ratos , Engenharia Tecidual , Alicerces Teciduais/química
12.
J Cell Physiol ; 232(12): 3396-3408, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28059444

RESUMO

Tumor necrosis factor α (TNF-α)-induced osteoclast formation have been demonstrated to play an important role in the pathogenesis of estrogen deficiency-mediated bone loss, but the exact mechanisms by which TNF-α enhanced osteoclast differentiation were not fully elucidated. The class III semaphorins members were critical to regulate bone homeostasis. Here, we identified a novel mechanism whereby TNF-α increasing Semaphorin3D expression contributes to estrogen deficiency-induced osteoporosis. In this study, we found that Semaphorin3D expression was upregulated by TNF-α during the process of RANKL-induced osteoclast differentiation. Inhibition of Semaphorin3D in pre-osteoclasts could attenuate the stimulatory effects of TNF-α on osteoclast proliferation and differentiation. Mechanistically, blocking of the Jun N-terminal kinase (JNK) signaling markedly rescued TNF-α-induced Semaphorin3D expression, suggesting that JNK signaling was involved in the regulation of Semaphorin3D expression by TNF-α. In addition, silencing of Semaphorin3D in vivo could alleviate estrogen deficiency-induced osteoporosis. Our results revealed a novel function for Semaphorin3D and suggested that increased Semaphorin3D may contribute to enhanced bone loss by increased TNF-α in estrogen deficiency-induced osteoporosis. Thus, Semaphorin3D may provide a potential therapeutic target for the treatment of estrogen-deficiency induced osteoporosis.


Assuntos
Estrogênios/metabolismo , Osteoclastos/metabolismo , Osteogênese , Osteoporose/metabolismo , Semaforinas/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Estrogênios/deficiência , Feminino , MAP Quinase Quinase 4/metabolismo , Camundongos Endogâmicos C57BL , Osteoclastos/citologia , Ovariectomia , Ligante RANK/metabolismo
13.
RNA ; 23(1): 1-5, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27742910

RESUMO

Multiplex genome engineering in vivo with CRISPR/Cas9 shows great promise as a potential therapeutic approach. The ability to incorporate multiple single guide RNA (sgRNA) cassettes together with Cas9 gene expression in one AAV vector could greatly enhance the efficiency. In a recent Method article, Mefferd and coworkers indicated that small tRNA promoters could be used to drive sgRNA expression to facilitate the construction of a more effective AAV vector. In contrast, we found that when targeting endogenous genomic loci, CRISPR/Cas9 with tRNA promoter-driven sgRNA expression showed much reduced genome editing activity, compared with significant cleavage with U6 promoter-driven sgRNA expression. Though the underlying mechanisms are still under investigation, our study suggests that the CRISPR/Cas9 system with tRNA promoter-driven sgRNA expression needs to be reevaluated before it can be used for therapeutic genome editing.


Assuntos
Exorribonucleases/genética , Edição de Genes/métodos , Regiões Promotoras Genéticas , RNA Guia de Cinetoplastídeos/genética , RNA de Transferência/genética , Sistemas CRISPR-Cas , Expressão Gênica
14.
Mol Cell Endocrinol ; 439: 133-140, 2017 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-27815211

RESUMO

Glycogen and triglyceride are two major forms of energy storage in the body and provide the fuel during different phases of food deprivation. However, how glycogen metabolism is linked to fat deposition in adipose tissue has not been clearly characterized. We generated a mouse model with whole-body deletion of PPP1R3G, a glycogen-targeting subunit of protein phosphatase-1 required for glycogen synthesis. Upon feeding with high-fat diet, the body weight and fat composition are significantly reduced in the PPP1R3G-/- mice compared to the wild type controls. The metabolic rate of the mice as measured by O2 consumption and CO2 production is accelerated by PPP1R3G deletion. The high-fat diet-induced liver steatosis is also slightly relieved by PPP1R3G deletion. The glycogen level in adipose tissue is reduced by PPP1R3G deletion. In 3T3L1 cells, overexpression of PPP1R3G leads to increases of both glycogen and triglyceride levels. In conclusion, our study indicates that glycogen is actively involved in fat accumulation in adipose tissue and obesity development upon high-fat diet. Our study also suggests that PPP1R3G is an important player that links glycogen metabolism to lipid metabolism in vivo.


Assuntos
Deleção de Genes , Glicogênio/metabolismo , Obesidade/metabolismo , Proteína Fosfatase 1/deficiência , Células 3T3-L1 , Adipócitos/metabolismo , Animais , Metabolismo Basal , Glicemia/metabolismo , Dieta Hiperlipídica , Fígado Gorduroso/sangue , Fígado Gorduroso/complicações , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Obesidade/sangue , Obesidade/complicações , Obesidade/patologia , Período Pós-Prandial , Proteína Fosfatase 1/metabolismo , Triglicerídeos/metabolismo
16.
Stem Cells Int ; 2016: 8283257, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27703485

RESUMO

Objective. Nucleus pulposus (NP) and annulus fibrosus (AF) are two main components of intervertebral disc (IVD). We aimed to figure out whether NP and AF also contain stem cells and whether these stem cells share common properties with chondrocytes and/or fibroblasts in their phenotypes or whether they are completely different types of cells with different characteristics. Design. The disk cells were isolated from AF and NP tissues of the same lumbar spine of the rabbits. The properties of these disk cells were characterized by their morphology, population doubling time (PDT), stem cell marker expression, and multidifferentiation potential using tissue culture techniques, immunocytochemistry, and RT-PCR. Results. Both disk cells formed colonies in culture and expressed stem cell markers, nucleostemin, Oct-4, SSEA-4, and Stro-1, at early passages. However, after 5 passages, AFSCs became elongated and NPSCs appeared senescent. Conclusion. This study indicated that IVD contains stem cells and the characteristics of AFSCs and NPSCs are intrinsically different. The findings of this study may provide basic scientific data for understanding the properties of IVD cells and the mechanisms of lower back pain.

18.
Arterioscler Thromb Vasc Biol ; 36(5): 783-6, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26941020

RESUMO

OBJECTIVE: Although early proof-of-concept studies of somatic in vivo genome editing of the mouse ortholog of proprotein convertase subtilisin/kexin type 9 (Pcsk9) in mice have established its therapeutic potential for the prevention of cardiovascular disease, the unique nature of genome-editing technology-permanent alteration of genomic DNA sequences-mandates that it be tested in vivo against human genes in normal human cells with human genomes to give reliable preclinical insights into the efficacy (on-target mutagenesis) and safety (lack of off-target mutagenesis) of genome-editing therapy before it can be used in patients. APPROACH AND RESULTS: We used a clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated (Cas) 9 genome-editing system to target the human PCSK9 gene in chimeric liver-humanized mice bearing human hepatocytes. We demonstrated high on-target mutagenesis (approaching 50%), greatly reduced blood levels of human PCSK9 protein, and minimal off-target mutagenesis. CONCLUSIONS: This work yields important information on the efficacy and safety of CRISPR-Cas9 therapy targeting the human PCSK9 gene in human hepatocytes in vivo, and it establishes humanized mice as a useful platform for the preclinical assessment of applications of somatic in vivo genome editing.


Assuntos
Proteínas Associadas a CRISPR/genética , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Edição de Genes/métodos , Marcação de Genes/métodos , Hepatócitos/enzimologia , Pró-Proteína Convertase 9/genética , Animais , Proteínas Associadas a CRISPR/metabolismo , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Regulação para Baixo , Genótipo , Hepatócitos/transplante , Humanos , Hidrolases/deficiência , Hidrolases/genética , Subunidade gama Comum de Receptores de Interleucina/deficiência , Subunidade gama Comum de Receptores de Interleucina/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mutação , Pró-Proteína Convertase 9/biossíntese , Pró-Proteína Convertase 9/sangue
19.
EMBO J ; 35(5): 496-514, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26834238

RESUMO

The Beclin1-VPS34 complex is recognized as a central node in regulating autophagy via interacting with diverse molecules such as ATG14L for autophagy initiation and UVRAG for autophagosome maturation. However, the underlying molecular mechanism that coordinates the timely activation of VPS34 complex is poorly understood. Here, we identify that PAQR3 governs the preferential formation and activation of ATG14L-linked VPS34 complex for autophagy initiation via two levels of regulation. Firstly, PAQR3 functions as a scaffold protein that facilitates the formation of ATG14L- but not UVRAG-linked VPS34 complex, leading to elevated capacity of PI(3)P generation ahead of starvation signals. Secondly, AMPK phosphorylates PAQR3 at threonine 32 and switches on PI(3)P production to initiate autophagosome formation swiftly after glucose starvation. Deletion of PAQR3 leads to reduction of exercise-induced autophagy in mice, accompanied by a certain degree of disaggregation of ATG14L-associated VPS34 complex. Together, this study uncovers that PAQR3 can not only enhance the capacity of pro-autophagy class III PI3K due to its scaffold function, but also integrate AMPK signal to activation of ATG14L-linked VPS34 complex upon glucose starvation.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Autofagia/fisiologia , Classe III de Fosfatidilinositol 3-Quinases/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Relacionadas à Autofagia , Proteína Beclina-1 , Glucose/deficiência , Células HEK293 , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Fígado/metabolismo , Masculino , Proteínas de Membrana , Camundongos Knockout , Músculo Esquelético/metabolismo , Corrida/fisiologia , Transdução de Sinais
20.
Bone ; 84: 78-87, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26723579

RESUMO

The proinflammatory cytokines, especially tumor necrosis factor alpha (TNF-α), have been shown to inhibit osteogenic differentiation of mesenchymal stem cells (MSCs) and bone formation in estrogen-deficiency-induced osteoporosis, but the mechanisms of TNF-α impaired bone formation remain poorly understood. Semaphorins have been shown to regulate cell growth, cell migration, and cell differentiation in a variety of tissues, including bone tissue. Here, we identified a novel mechanism whereby TNF-α, suppressing Semaphorin3B expression contributes to estrogen-deficiency-induced osteoporosis. In this study, we found that TNF-α could decrease Semaphorin3B expression in osteogenic differentiation of MSCs. Overexpression of Semaphorin3B in MSCs attenuated the inhibitory effects of TNF-α on MSCs proliferation and osteoblastic differentiation. Mechanistically, activation of the Wnt/ß-catenin signaling markedly rescued TNF-α-inhibited Semaphorin3B expression, suggesting that Wnt/ß-catenin signaling was involved in the regulation of Semaphorin3B expression by TNF-α. Taken together, our results revealed a novel function for Semaphorin3B and suggested that suppressed Semaphorin3B may contribute to impaired bone formation by elevated TNF-α in estrogen-deficiency-induced osteoporosis. This study may indicate a therapeutic target gene of Semaphorin3B for osteoporosis.


Assuntos
Diferenciação Celular , Estrogênios/deficiência , Células-Tronco Mesenquimais/citologia , Osteogênese , Osteoporose/etiologia , Semaforinas/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Via de Sinalização Wnt , Animais , Proliferação de Células , Feminino , Células-Tronco Mesenquimais/metabolismo , Camundongos Endogâmicos C57BL , Osteoporose/metabolismo , Ovariectomia , Semaforinas/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...