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1.
Nature ; 630(8016): 484-492, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38811729

RESUMEN

The CRISPR system is an adaptive immune system found in prokaryotes that defends host cells against the invasion of foreign DNA1. As part of the ongoing struggle between phages and the bacterial immune system, the CRISPR system has evolved into various types, each with distinct functionalities2. Type II Cas9 is the most extensively studied of these systems and has diverse subtypes. It remains uncertain whether members of this family can evolve additional mechanisms to counter viral invasions3,4. Here we identify 2,062 complete Cas9 loci, predict the structures of their associated proteins and reveal three structural growth trajectories for type II-C Cas9. We found that novel associated genes (NAGs) tended to be present within the loci of larger II-C Cas9s. Further investigation revealed that CbCas9 from Chryseobacterium species contains a novel ß-REC2 domain, and forms a heterotetrameric complex with an NAG-encoded CRISPR-Cas-system-promoting (pro-CRISPR) protein of II-C Cas9 (PcrIIC1). The CbCas9-PcrIIC1 complex exhibits enhanced DNA binding and cleavage activity, broader compatibility for protospacer adjacent motif sequences, increased tolerance for mismatches and improved anti-phage immunity, compared with stand-alone CbCas9. Overall, our work sheds light on the diversity and 'growth evolutionary' trajectories of II-C Cas9 proteins at the structural level, and identifies many NAGs-such as PcrIIC1, which serves as a pro-CRISPR factor to enhance CRISPR-mediated immunity.


Asunto(s)
Bacterias , Bacteriófagos , Proteína 9 Asociada a CRISPR , Sistemas CRISPR-Cas , Bacterias/virología , Bacterias/genética , Bacterias/inmunología , Bacteriófagos/genética , Bacteriófagos/inmunología , Chryseobacterium/genética , Chryseobacterium/inmunología , Chryseobacterium/virología , Proteína 9 Asociada a CRISPR/química , Proteína 9 Asociada a CRISPR/genética , Proteína 9 Asociada a CRISPR/metabolismo , Sistemas CRISPR-Cas/genética , Sistemas CRISPR-Cas/inmunología , División del ADN , Sitios Genéticos/genética , Modelos Moleculares , Dominios Proteicos
2.
SSM Popul Health ; 26: 101673, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38779456

RESUMEN

Lifestyles are associated with all-cause mortality, yet limited research has explored the association in the elderly population with multimorbidity. We aim to investigate the impact of adopting a healthy lifestyle on reducing the risk of all-cause mortality in older individuals with or without multimorbidity in both China and UK. This prospective study included 29,451 and 173,503 older adults aged 60 and over from Chinese Longitudinal Healthy Longevity Survey (CLHLS) and UK Biobank. Lifestyles and multimorbidity were categorized into three groups, respectively. Cox proportional hazards regression was used to estimate the Hazard Ratios (HRs), 95% confidence intervals (95% CIs), and dose-response for all-cause mortality in relation to lifestyles and multimorbidity, as well as the combination of both factors. During a mean follow-up period of 4.7 years in CLHLS and 12.14 years in UK Biobank, we observed 21,540 and 20,720 deaths, respectively. For participants with two or more conditions, compared to those with an unhealthy lifestyle, adopting a healthy lifestyle was associated with a 27%-41% and 22%-42% reduction in mortality risk in the CLHLS and UK Biobank, respectively; Similarly, for individuals without multimorbidity, this reduction ranged from 18% to 41%. Among participants with multimorbidity, individuals with an unhealthy lifestyle had a higher mortality risk compared to those maintaining a healthy lifestyle, with HRs of 1.15 (95% CI: 1.00, 1.32) and 1.27 (95% CI: 1.16, 1.39) for two conditions, and 1.24 (95% CI: 1.06, 1.45) and 1.73 (95% CI: 1.56, 1.91) for three or more conditions in CLHLS and UK Biobank, respectively. Adherence to a healthy lifestyle can yield comparable mortality benefits for older individuals, regardless of their multimorbidity status. Furthermore, maintaining a healthy lifestyle can alleviate the mortality risks linked to a higher number of diseases.

3.
Crit Rev Eukaryot Gene Expr ; 34(4): 33-44, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38505871

RESUMEN

Acute myeloid leukemia (AML) is a highly heterogeneous disease. Exploring the pathogenesis of AML is still an important topic in the treatment of AML. The expression levels of miR-26b-5p and USP48 were measured by qRT-PCR. The expression levels of related proteins were detected by Western blot. Cell proliferation and apoptosis were detected by CCK-8 and flow cytometry, respectively. Coimmunoprecipitation was used to examine the interaction between USP48 and Wnt5a. Bioinformatics analysis showed that high levels of miR-26b-5p and low levels of USP48 were associated with poor prognosis in AML. miR-26b-5p can negatively regulate the expression of USP48. Downregulation of miR-26b-5p inhibited EMT, cell viability and proliferation of AML cells and accelerated apoptosis. Furthermore, the influence of miR-26b-5p inhibition and USP48 knockdown on AML progression could be reversed by a Wnt/ß-catenin signaling pathway inhibitor. This study revealed that miR-26b-5p regulates AML progression, possibly by targeting the USP48-mediated Wnt/ß-catenin molecular axis to affect AML cell biological behavior.


Asunto(s)
Leucemia Mieloide Aguda , MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Vía de Señalización Wnt/genética , beta Catenina/genética , Western Blotting , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Proliferación Celular/genética , Línea Celular Tumoral , Apoptosis/genética , Proteasas Ubiquitina-Específicas/metabolismo
4.
Artículo en Inglés | MEDLINE | ID: mdl-38450723

RESUMEN

BACKGROUND: The effect of a healthy lifestyle on dementia associated with multimorbidity is not well understood. Our objective is to examine whether the adoption of a healthy lifestyle could potentially reduce the elevated risk of dementia in individuals with and without multimorbidity. METHODS: We utilized data from the UK Biobank cohort. A comprehensive healthy lifestyle score, ranging from 0 to 6, was generated. Cox proportional hazards models were used to examine the associations between multimorbidity, the healthy lifestyle score, and the incidence risk of dementia. RESULTS: Over a median follow-up period of 12.5 years, 5 852 all-cause dementia were recorded. Multimorbidity including cardiovascular, metabolic, neuropsychiatric, and inflammation-related diseases was associated with a higher risk of subsequent dementia. Each additional chronic disease was associated with a hazard ratio (HR) of 1.38 (95% CI: 1.33, 1.44). Compared to individuals without multimorbidity and a healthy lifestyle score of 5-6, patients with multimorbidity and a lifestyle score of 0-1 had a significantly higher risk of dementia (HR: 3.13; 95% CI: 2.64, 3.72), but the risk was markedly attenuated among those with multimorbidity and a lifestyle score of 5-6. Among patients with 3 or more diseases, the HR for dementia was 0.53 (95%CI: 0.42, 0.68) when comparing a lifestyle score of 5-6 to 0-1. And we observed more pronounced association between them among people younger than 60 years old. CONCLUSIONS: Adherence to a combination of healthy lifestyle factors, especially at a young age, was associated with a significantly lower risk of dementia among participants with multimorbidity.


Asunto(s)
Demencia , Multimorbilidad , Humanos , Estudios Prospectivos , Factores de Riesgo , Estilo de Vida , Estilo de Vida Saludable , Demencia/epidemiología , Demencia/etiología
5.
Chemistry ; 30(25): e202304296, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38380537

RESUMEN

Sodium/potassium-ion batteries (NIBs and KIBs) are considered the most promising candidates for lithium-ion batteries in energy storage fields. Tin sulfide (SnS2) is regarded as an attractive negative candidate for NIBs and KIBs thanks to its superior power density, high-rate performance and natural richness. Nevertheless, the slow dynamics, the enormous volume change and the decomposition of polysulfide intermediates limit its practical application. Herein, microcubes SnS2 were prepared through sacrificial MnCO3 template-assisted and a facile solvothermal reaction strategy and their performance was investigated in Na and K-based cells. The unique hollow cubic structure and well-confined SnS2 nanosheets play an important role in Na+/K+ rapid kinetic and alleviating volume change. The effect of the carbon additives (Super P/C65) on the electrochemical properties were investigated thoroughly. The in operando and ex-situ characterization provide a piece of direct evidence to clarify the storage mechanism of such conversion-alloying type negative electrode materials.

6.
Science ; 383(6682): eadh4859, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38301022

RESUMEN

Ribozymes are catalytic RNAs with diverse functions including self-splicing and polymerization. This work aims to discover natural ribozymes that behave as hydrolytic and sequence-specific DNA endonucleases, which could be repurposed as DNA manipulation tools. Focused on bacterial group II-C introns, we found that many systems without intron-encoded protein propagate multiple copies in their resident genomes. These introns, named HYdrolytic Endonucleolytic Ribozymes (HYERs), cleaved RNA, single-stranded DNA, bubbled double-stranded DNA (dsDNA), and plasmids in vitro. HYER1 generated dsDNA breaks in the mammalian genome. Cryo-electron microscopy analysis revealed a homodimer structure for HYER1, where each monomer contains a Mg2+-dependent hydrolysis pocket and captures DNA complementary to the target recognition site (TRS). Rational designs including TRS extension, recruiting sequence insertion, and heterodimerization yielded engineered HYERs showing improved specificity and flexibility for DNA manipulation.


Asunto(s)
División del ADN , Endonucleasas , ARN Catalítico , Animales , Microscopía por Crioelectrón , Endonucleasas/química , Endonucleasas/genética , Hidrólisis , Intrones , Conformación de Ácido Nucleico , Empalme del ARN , ARN Catalítico/química , ARN Catalítico/genética
7.
Gene ; 894: 147949, 2024 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-37918547

RESUMEN

Alternative polyadenylation (APA) is a key molecular mechanism involved in the post-transcriptional regulation of gene expression, which has been proven to play a critical role in cell differentiation. In the present study, we performed IVT-SAPAS sequencing to profile the dynamic changes of APA sites in bovine subcutaneous preadipocytes and intramuscular preadipocytes during adipogenesis. A total of 52621 high quality APA sites were identified in preadipocytes and adipocytes. Compared with preadipocytes, the increased usage of canonical AATAAA was observed in the cell-biased APA sites of adipocytes. Furthermore, 1933 and 2140 differentially expressed APA (DE-APA) sites, as well as 341 and 337 untranslated region-APA (UTR-APA) switching genes were identified in subcutaneous preadipocytes and intramuscular preadipocytes during adipogenesis, respectively. The UTR-APA switching genes showed divergent trends in preadipocytes, among which UTR-APA switching genes in intramuscular preadipocytes tended to use shorter 3'UTR for differentiation into mature adipocytes. APA events mediated by UTR-APA switching in intramuscular adipocytes were enriched in lipid synthesis and adipocyte differentiation. TRIB3, WWTR1, and INSIG1 played important roles in the differentiation of intramuscular preadipocytes. Briefly, our results provided new insights into understanding the mechanisms of bovine adipocyte differentiation.


Asunto(s)
Tejido Adiposo , Poliadenilación , Bovinos , Animales , Tejido Adiposo/metabolismo , Adipocitos/metabolismo , Diferenciación Celular/genética , Adipogénesis/genética
8.
J Agric Food Chem ; 71(51): 20815-20825, 2023 Dec 27.
Artículo en Inglés | MEDLINE | ID: mdl-38088871

RESUMEN

Understanding the mechanism of adipogenesis is an important basis for improving meat quality traits of livestock. Alternative polyadenylation (APA) is a vital mechanism to regulate the expression of eukaryotic genes. However, how the individual APA functions in adipogenesis remains elusive. This study was intended to investigate the effect of malic enzyme 1 (ME1) APA on adipogenesis. Here, intracellular lipid droplets were stained using Oil red O. 3' RACE was used to verify APA events of the ME1 gene. Interactions between ME1 3' untranslated region (3' UTR)-APA isoforms and miRNAs, as well as differential expression of isoforms, were examined using dual-luciferase reporter and molecular experiments. The mechanism of ME1 APA on adipogenesis was explored by gain and loss of function assays. In this study, two ME1 isoforms with different 3' UTR lengths were detected during adipogenesis. Moreover, the ME1 isoform with a short 3' UTR was significantly upregulated compared with the one with a long 3' UTR. Mechanistically, only the long ME1 isoform was targeted by miR-153-3p to attenuate adipogenesis, while the short one escaped the regulation of miR-153-3p to accelerate adipogenesis. Our results reveal a novel mechanism of ME1 APA in regulating adipogenesis.


Asunto(s)
MicroARNs , Poliadenilación , Regiones no Traducidas 3' , Adipogénesis , MicroARNs/genética , MicroARNs/metabolismo , Isoformas de Proteínas/genética
9.
Animals (Basel) ; 13(19)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37835681

RESUMEN

Alternative polyadenylation (APA), including APA that occurs only in the 3' UTR (3' UTR-APA), is an important post-transcriptional regulatory mechanism that leads to distinct 3' UTRs for some genes, increasing the complexity of the transcriptome. The post-transcriptional events regulating the expression of bovine, the C-X-C motif chemokine ligand 14 (CXCL14) gene, remains largely unknown. Here, we find that the bovine CXCL14 gene produces two different lengths of mRNA isoforms due to 3' UTR-APA, and the short and long 3' UTR is 126 bp and 1155 bp, respectively. We found that the expression level of the short isoform was significantly higher than that of the long isoform by luciferase assays and overexpression of different CXCL14 3' UTR-APA isoforms. Moreover, using luciferase assay and site-directed mutagenesis experiments, the results showed that the long CXCL14 3' UTR-APA isoform is downregulated by miR-17-5p, miR-150, and miR-217. However, because the short isoform lacks the true target of miR-17-5p, miR-150, and miR-217 in its 3' UTR and thus escapes the inhibitory effect of these microRNAs, its expression level is significantly higher than that of the long isoform. Finally, we demonstrate that the short CXCL14 3' UTR-APA isoform promotes preadipocyte proliferation by cell counting kit 8 (CCK8) assays. Collectively, our results show that the CXCL14 gene is post-transcriptionally regulated through APA and microRNAs.

10.
Exp Hematol ; 128: 77-88, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37805161

RESUMEN

Acute myeloid leukemia (AML) is one of the deadliest hematologic malignancies, and its targeted therapy has developed slowly. The molecular mechanism of the pathophysiology of the disease remains to be clarified. The aim of our study was to probe the specific regulatory mechanism of miR-455-3p in AML. This study measured the levels of miR-455-3p and ubinuclein-2 (UBN2) in AML cell lines, evaluated cell viability with CCK-8, used flow cytometry to estimate the cell cycle and apoptosis, detected cell apoptosis and autophagy-related protein levels by Western blotting, and added 50 µM chloroquine (CQ) to evaluate the relationship between autophagy and AML. In animal experiments, HL-60 cells were injected into male non-obese diabetic/severe combined immunodeficiency disease (NOD/SCID) mice through the tail vein to determine survival time and observe the degree of liver and spleen damage in the mice. miR-455-3p was prominently reduced in the peripheral blood and AML cell lines, and UBN2 showed high expression. The transfected miR-455-3p mimic effectively restrained the activity of AML cells, whereas overexpression of UBN2 or the addition of the autophagy inhibitor CQ reversed the effect of miR-455-3p. The interaction between UBN2 and peroxisome proliferator-activated receptor alpha (PPARα) was confirmed by coimmunoprecipitation, and overexpression of PPARα reversed the promoting effect of UBN2 knockdown on apoptosis and autophagy in AML cells. In conclusion, miR-455-3p mediates PPARα protein expression through UBN2, exacerbating AML cell apoptosis and autophagy. This study found that miR-455-3p plays an important role in AML cell apoptosis and autophagy, which may provide novel insights for the treatment of AML diseases.


Asunto(s)
Apoptosis , Autofagia , Leucemia Mieloide Aguda , MicroARNs , PPAR alfa , Factores de Transcripción , Animales , Masculino , Ratones , Línea Celular Tumoral , Proliferación Celular , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Ratones Endogámicos NOD , Ratones SCID , MicroARNs/metabolismo , PPAR alfa/metabolismo , Factores de Transcripción/metabolismo
11.
Int J Cancer ; 153(6): 1273-1286, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37334524

RESUMEN

Chemotherapy is the standard therapy for small cell lung cancer (SCLC), but relapse is common and the 2-year survival rate remains low. Given the contribution of the tumor microenvironment (TME) to cancer development and response to treatment, we analyzed here how chemotherapy alters the TME in SCLC using single-cell RNA sequencing. The comparison between neuroendocrine cells and other epithelial cells in five chemotherapy-naive patients identified upregulation of Notch-inhibiting genes, such as DLL3 and HES6. Analysis of genes differentially expressed between five patients receiving chemotherapy and five treatment-naive patients in cells in the TME showed that chemotherapy promoted antigen presentation and senescence in neuroendocrine cells, upregulated ID1 to enhance angiogenic activities of stalk-like endothelial cells and strengthened vascular endothelial growth factor signaling in lymphatic endothelial cells. Chemotherapy also promoted the remodeling of extracellular matrix by fibroblasts and upregulated interferon-mediated antitumor immune responses by B and T cells. Our single-cell transcriptome analysis provides insights into how chemotherapy affects the TME in SCLC, which may guide efforts to make therapy more effective.


Asunto(s)
Neoplasias Pulmonares , Carcinoma Pulmonar de Células Pequeñas , Humanos , Carcinoma Pulmonar de Células Pequeñas/tratamiento farmacológico , Carcinoma Pulmonar de Células Pequeñas/genética , Carcinoma Pulmonar de Células Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Células Endoteliales/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Análisis de Expresión Génica de una Sola Célula , Recurrencia Local de Neoplasia , Microambiente Tumoral/genética , Transcriptoma , Proteínas de la Membrana/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo
12.
Cell Res ; 33(3): 229-244, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36650285

RESUMEN

CRISPR-Cas modules serve as the adaptive nucleic acid immune systems for prokaryotes, and provide versatile tools for nucleic acid manipulation in various organisms. Here, we discovered a new miniature type V system, CRISPR-Casπ (Cas12l) (~860 aa), from the environmental metagenome. Complexed with a large guide RNA (~170 nt) comprising the tracrRNA and crRNA, Casπ (Cas12l) recognizes a unique 5' C-rich PAM for DNA cleavage under a broad range of biochemical conditions, and generates gene editing in mammalian cells. Cryo-EM study reveals a 'bracelet' architecture of Casπ effector encircling the DNA target at 3.4 Å resolution, substantially different from the canonical 'two-lobe' architectures of Cas12 and Cas9 nucleases. The large guide RNA serves as a 'two-arm' scaffold for effector assembly. Our study expands the knowledge of DNA targeting mechanisms by CRISPR effectors, and offers an efficient but compact platform for DNA manipulation.


Asunto(s)
ADN , Edición Génica , ADN/genética , Endonucleasas/genética , Sistemas CRISPR-Cas , ARN Guía de Sistemas CRISPR-Cas
13.
ChemSusChem ; 16(7): e202202281, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36593175

RESUMEN

Sodium-ion and potassium-ion batteries (NIBs and KIBs) are considered promising alternatives to replace lithium-ion batteries (LIBs) in energy storage applications due to the natural abundance and low cost of Na and K. Nevertheless, a critical challenge is that the large size of Na+ /K+ leads to a huge volume change of the hosting material during electrochemical cycling, resulting in rapid capacity decay. Among negative candidates for alkali-metal-ion batteries, SnS2 is attractive due to the competitively high specific capacity, low redox potential and high abundance. Porous few-layer SnS2 nanosheets are in situ grown on reduced graphene oxide, forming a SnS2 -rGO sandwich structure via strong C-O-Sn bonds. This nano-scaled sandwich structure not only shortens Na+ /K+ and electron transport pathways but also accommodates volume expansion, thereby enabling high and stable electrochemical cycling performance of SnS2 -rGO. This work explores the influence of different conductive carbons (Super P and C65) on the SnS2 -rGO electrode. In addition, the effects of the electrolyte additive fluoroethylene carbonate (FEC) on the electrochemical performance in NIBs and KIBs is evaluated. This work provides guidelines for optimized electrode structure design, electrolyte additives and carbon additives for the realization of better NIBs and KIBs.

14.
Artículo en Inglés | MEDLINE | ID: mdl-36141516

RESUMEN

The treatment of arsenic (As) in tin tailings (TT) has been an urgent environmental problem, and stabilization/solidification (S/S) treatment is considered an effective technology to eliminate contamination of As. In this study, we developed a low-carbon and low-alkalinity material to S/S of As, and the results showed that the leaching concentration of As after treatment was lower than the Chinese soil environmental quality standard (0.1 mg/L). Based on a series of characterization tests, we found that OH- promoted the dissolution of As(III)-S, Fe-As(V), and amorphous As(III)-O species and formed Ca-As(III) and Ca-(V) species with Ca2+. Simultaneously, hydration produces calcium silicate hydrate (C-S-H) gel and ettringite by the form of adsorption and ion exchange to achieve S/S of As. We also assessed the durability of this material to acidity and temperature, and showed that the leaching concentration of As was below 0.1 mg/L at pH = 1-5 and temperature 20-60 °C. The method proposed in this study, S/S of As, has excellent effect and environmental durability, providing a new solution for harmless treatment of TT and its practical application.


Asunto(s)
Arsénico , Adsorción , Arsénico/química , Carbono/química , Suelo , Estaño
15.
Mol Cell ; 82(6): 1199-1209.e6, 2022 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-35219382

RESUMEN

A compact protein with a size of <1,000 amino acids, the CRISPR-associated protein CasX is a fundamentally distinct RNA-guided nuclease when compared to Cas9 and Cas12a. Although it can induce RNA-guided genome editing in mammalian cells, the activity of CasX is less robust than that of the widely used S. pyogenes Cas9. Here, we show that structural features of two CasX homologs and their guide RNAs affect the R-loop complex assembly and DNA cleavage activity. Cryo-EM-based structural engineering of either the CasX protein or the guide RNA produced two new CasX genome editors (DpbCasX-R3-v2 and PlmCasX-R1-v2) with significantly improved DNA manipulation efficacy. These results advance both the mechanistic understanding of CasX and its application as a genome-editing tool.


Asunto(s)
Edición Génica , ARN Guía de Kinetoplastida , Animales , Sistemas CRISPR-Cas/genética , Endonucleasas/genética , Endonucleasas/metabolismo , Edición Génica/métodos , Mamíferos/metabolismo , ARN/genética , ARN Guía de Kinetoplastida/genética , ARN Guía de Kinetoplastida/metabolismo
16.
Front Cell Dev Biol ; 9: 705302, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34422825

RESUMEN

Liver regeneration is a key compensatory process in response to liver injury serving to contain damages and to rescue liver functions. Hepatocytes, having temporarily exited the cell cycle after embryogenesis, resume proliferation to regenerate the injured liver parenchyma. In the present study we investigated the transcriptional regulation of choline kinase alpha (Chka) in hepatocytes in the context of liver regeneration. We report that Chka expression was significantly up-regulated in the regenerating livers in the partial hepatectomy (PHx) model and the acetaminophen (APAP) injection model. In addition, treatment with hepatocyte growth factor (HGF), a strong pro-proliferative cue, stimulated Chka expression in primary hepatocytes. Chka depletion attenuated HGF-induced proliferation of hepatocytes as evidenced by quantitative PCR and Western blotting measurements of pro-proliferative genes as well as EdU incorporation into replicating DNA. Of interest, deletion of Brahma-related gene 1 (Brg1), a chromatin remodeling protein, attenuated Chka induction in the regenerating livers in mice and in cultured hepatocytes. Further analysis revealed that Brg1 interacted with hypoxia-inducible factor 1 alpha (HIF-1α) to directly bind to the Chka promoter and activate Chka transcription. Finally, examination of human acute liver failure (ALF) specimens identified a positive correlation between Chka expression and Brg1 expression. In conclusion, our data suggest that Brg1-dependent trans-activation of Chka expression may contribute to liver regeneration.

17.
Redox Biol ; 46: 102079, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34454163

RESUMEN

Liver injuries induced by various stimuli share in common an acute inflammatory response, in which circulating macrophages home to the liver parenchyma to participate in the regulation of repair, regeneration, and fibrosis. In the present study we investigated the role of hepatocyte-derived C-C motif ligand 7 (CCL7) in macrophage migration during liver injury focusing on its transcriptional regulation. We report that CCL7 expression was up-regulated in the liver by lipopolysaccharide (LPS) injection (acute liver injury) or methionine-and-choline-deficient (MCD) diet feeding (chronic liver injury) paralleling increased macrophage infiltration. CCL7 expression was also inducible in hepatocytes, but not in hepatic stellate cells or in Kupffer cells, by LPS treatment or exposure to palmitate in vitro. Hepatocyte-specific deletion of Brahma-related gene 1 (BRG1), a chromatin remodeling protein, resulted in a concomitant loss of CCL7 induction and macrophage infiltration in the murine livers. Of interest, BRG1-induced CCL7 transcription and macrophage migration was completely blocked by the antioxidant N-acetylcystine. Further analyses revealed that BRG1 interacted with activator protein 1 (AP-1) to regulate CCL7 transcription in hepatocytes in a redox-sensitive manner mediated in part by casein kinase 2 (CK2)-catalyzed phosphorylation of BRG1. Importantly, a positive correlation between BRG1/CCL7 expression and macrophage infiltration was identified in human liver biopsy specimens. In conclusion, our data unveil a novel role for BRG1 as a redox-sensitive activator of CCL7 transcription.


Asunto(s)
ADN Helicasas , Proteínas Nucleares , Animales , Células Cultivadas , Quimiocina CCL7/metabolismo , Hepatocitos/metabolismo , Humanos , Hígado/metabolismo , Ratones , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Oxidación-Reducción , Factores de Transcripción
18.
J Agric Food Chem ; 69(28): 8038-8049, 2021 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-34236846

RESUMEN

Appropriately increasing intramuscular fat content can help improve meat quality, so it is necessary to explore the internal molecular mechanism of preadipocyte differentiation. The role of heme oxygenase 1 (HO1) in cell oxidative stress, energy metabolism, cell proliferation, and differentiation has gradually been revealed. Here, we used 3'RACE to identify the full-length 3' untranslated region (3'UTR) of HO1 and found that a very short 3'UTR variant was produced by alternative polyadenylation (APA). HO1 with a long 3'UTR variant was identified as a direct target of miR155-5P and miR377-3P. Our experimental results verified the inhibitory effect of HO1 on preadipocyte differentiation. In addition, our research confirms that by escaping microRNA inhibitory effects, the HO1 3'UTR short variant produced by APA has a higher level of expression. Thus, the HO1 3'UTR short variant has a stronger inhibitory effect on the preadipocyte differentiation than the HO1 3'UTR long variants in 3T3-L1.


Asunto(s)
MicroARNs , Poliadenilación , Regiones no Traducidas 3' , Células 3T3-L1 , Adipogénesis/genética , Animales , Hemo-Oxigenasa 1/genética , Proteínas de la Membrana , Ratones , MicroARNs/genética , MicroARNs/metabolismo
19.
Br J Haematol ; 192(5): 900-908, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33534930

RESUMEN

The development of alloantibodies (inhibitors) against coagulation factor VIII (FVIII) is the most serious complication of FVIII replacement therapy in patients with haemophilia A (HA). We carried out a nationwide study focussing on patients with HA with inhibitors in China to evaluate the condition and management of this population. The study retrospectively analysed patient characteristics, clinical history, manifestation, treatment strategy as well as individual haemophilia care of 493 patients with inhibitors (466 with severe HA and 27 with non-severe HA) registered all over China. The median (interquartile range) age at diagnosis of FVIII inhibitors was 13 (5-28) years in patients with severe HA and 24 (10·5-39·5) years in patients with non-severe HA. Most patients (85%) had high-titre inhibitors. Prothrombin complex concentrate and recombinant activated coagulation factor VII were used respectively in 76·2% and 29·2% of patients for acute bleeding. Only 22·3% of patients underwent immune tolerance induction (ITI) treatment, of whom 64·9% achieved negative inhibitor titre. In patients who did not undergo ITI, the inhibitors turned negative in 17·7%, and patients with low peak inhibitor titre were more likely to acquire negative titre spontaneously (odds ratio 11·524, 95% confidence interval 5·222-25·432; P = 0·000). We recorded that 3·2% of the patients died from haemophilia-related life-threatening bleeding.


Asunto(s)
Factor VIII/inmunología , Hemofilia A/inmunología , Isoanticuerpos/inmunología , Adolescente , Adulto , Anciano , Anticuerpos Biespecíficos/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Factores de Coagulación Sanguínea/uso terapéutico , Niño , Preescolar , China/epidemiología , Factor VIII/uso terapéutico , Factor VIIa/uso terapéutico , Estudios de Seguimiento , Hemofilia A/complicaciones , Hemofilia A/tratamiento farmacológico , Hemofilia A/epidemiología , Hemorragia/tratamiento farmacológico , Hemorragia/etiología , Hemostáticos/provisión & distribución , Hemostáticos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/uso terapéutico , Sistema de Registros , Índice de Severidad de la Enfermedad , Adulto Joven
20.
Ann Transl Med ; 8(22): 1496, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33313241

RESUMEN

BACKGROUND: Proliferation and migration of vascular smooth muscle cells (VSMCs) are vital processes in vascular remodeling and pathology. This study aimed to explore the expression of miR-29b and cell division cycle 7-related protein kinase (CDC7) in patients with cerebral aneurysm (CA) and their effects on the proliferation and mobility of human umbilical artery smooth muscle cells (HUASMCs). METHODS: RNA levels of miR-29b and CDC7 were evaluated in the CA tissues and adjacent normal cerebral arteries from 18 patients undergoing surgery for CA rupture. The targeting of CDC7 by miR-29b was verified with luciferase reporter assay. Both CDC7 and miR-29b overexpression and silencing vectors were introduced to validate their effects on the proliferation and mobility of HUASMCs. RESULTS: The mRNA level of miR-29b was down-regulated (P<0.05), while the mRNA level of CDC7 was markedly elevated in CA patients (P<0.05). A Luciferase reporter assay showed CDC7 is a target gene of miR-29b, and miR-29b mimic down-regulated the mRNA and protein levels of CDC7 (P<0.05). Furthermore, miR-29b mimic inhibited, while miR-29b inhibitor or CDC7 over-expression promoted the proliferation and mobility of HUASMCs (P<0.05). CONCLUSIONS: miR-29-3p inhibits cell proliferation and mobility via directly targeting CDC7, which could be a potential therapeutic target for vascular dysfunction related diseases, including atherosclerosis and CA.

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