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1.
Cell ; 187(9): 2129-2142.e17, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38670071

RESUMEN

Interspecies blastocyst complementation (IBC) provides a unique platform to study development and holds the potential to overcome worldwide organ shortages. Despite recent successes, brain tissue has not been achieved through IBC. Here, we developed an optimized IBC strategy based on C-CRISPR, which facilitated rapid screening of candidate genes and identified that Hesx1 deficiency supported the generation of rat forebrain tissue in mice via IBC. Xenogeneic rat forebrain tissues in adult mice were structurally and functionally intact. Cross-species comparative analyses revealed that rat forebrain tissues developed at the same pace as the mouse host but maintained rat-like transcriptome profiles. The chimeric rate of rat cells gradually decreased as development progressed, suggesting xenogeneic barriers during mid-to-late pre-natal development. Interspecies forebrain complementation opens the door for studying evolutionarily conserved and divergent mechanisms underlying brain development and cognitive function. The C-CRISPR-based IBC strategy holds great potential to broaden the study and application of interspecies organogenesis.


Asunto(s)
Prosencéfalo , Animales , Prosencéfalo/metabolismo , Prosencéfalo/embriología , Ratones , Ratas , Blastocisto/metabolismo , Femenino , Sistemas CRISPR-Cas/genética , Transcriptoma , Organogénesis , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Masculino , Ratones Endogámicos C57BL
2.
Cell ; 187(9): 2305-2323.e33, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38614099

RESUMEN

Cancer immunotherapy has transformed treatment possibilities, but its effectiveness differs significantly among patients, indicating the presence of alternative pathways for immune evasion. Here, we show that ITPRIPL1 functions as an inhibitory ligand of CD3ε, and its expression inhibits T cells in the tumor microenvironment. The binding of ITPRIPL1 extracellular domain to CD3ε on T cells significantly decreased calcium influx and ZAP70 phosphorylation, impeding initial T cell activation. Treatment with a neutralizing antibody against ITPRIPL1 restrained tumor growth and promoted T cell infiltration in mouse models across various solid tumor types. The antibody targeting canine ITPRIPL1 exhibited notable therapeutic efficacy against naturally occurring tumors in pet clinics. These findings highlight the role of ITPRIPL1 (or CD3L1, CD3ε ligand 1) in impeding T cell activation during the critical "signal one" phase. This discovery positions ITPRIPL1 as a promising therapeutic target against multiple tumor types.


Asunto(s)
Complejo CD3 , Activación de Linfocitos , Linfocitos T , Escape del Tumor , Microambiente Tumoral , Animales , Complejo CD3/metabolismo , Complejo CD3/inmunología , Humanos , Ratones , Linfocitos T/inmunología , Linfocitos T/metabolismo , Microambiente Tumoral/inmunología , Perros , Neoplasias/inmunología , Línea Celular Tumoral , Femenino , Unión Proteica , Proteína Tirosina Quinasa ZAP-70/metabolismo , Anticuerpos Neutralizantes/inmunología , Ratones Endogámicos C57BL
3.
Cell ; 168(3): 517-526.e18, 2017 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-28111075

RESUMEN

The gut microbiota modulate host biology in numerous ways, but little is known about the molecular mediators of these interactions. Previously, we found a widely distributed family of nonribosomal peptide synthetase gene clusters in gut bacteria. Here, by expressing a subset of these clusters in Escherichia coli or Bacillus subtilis, we show that they encode pyrazinones and dihydropyrazinones. At least one of the 47 clusters is present in 88% of the National Institutes of Health Human Microbiome Project (NIH HMP) stool samples, and they are transcribed under conditions of host colonization. We present evidence that the active form of these molecules is the initially released peptide aldehyde, which bears potent protease inhibitory activity and selectively targets a subset of cathepsins in human cell proteomes. Our findings show that an approach combining bioinformatics, synthetic biology, and heterologous gene cluster expression can rapidly expand our knowledge of the metabolic potential of the microbiota while avoiding the challenges of cultivating fastidious commensals.


Asunto(s)
Bacterias/metabolismo , Microbioma Gastrointestinal , Microbiota , Péptido Sintasas/metabolismo , Pirazinas/metabolismo , Animales , Bacillus subtilis/genética , Bacterias/clasificación , Bacterias/genética , Escherichia coli/genética , Heces/microbiología , Humanos , Péptido Sintasas/genética , Filogenia
4.
Immunity ; 54(10): 2231-2244.e6, 2021 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-34555337

RESUMEN

RNA interference (RNAi) is the major antiviral mechanism in plants and invertebrates, but the absence of detectable viral (v)siRNAs in mammalian cells upon viral infection has questioned the functional relevance of this pathway in mammalian immunity. We designed a series of peptides specifically targeting enterovirus A71 (EV-A71)-encoded protein 3A, a viral suppressor of RNAi (VSR). These peptides abrogated the VSR function of EV-A71 in infected cells and resulted in the accumulation of vsiRNAs and reduced viral replication. These vsiRNAs were functional, as evidenced by RISC-loading and silencing of target RNAs. The effects of VSR-targeting peptides (VTPs) on infection with EV-A71 as well as another enterovirus, Coxsackievirus-A16, were ablated upon deletion of Dicer1 or AGO2, core components of the RNAi pathway. In vivo, VTP treatment protected mice against lethal EV-A71 challenge, with detectable vsiRNAs. Our findings provide evidence for the functional relevance of RNAi in mammalian immunity and present a therapeutic strategy for infectious disease.


Asunto(s)
Antivirales/farmacología , Infecciones por Enterovirus/virología , ARN Viral/antagonistas & inhibidores , Animales , Chlorocebus aethiops , Enterovirus Humano A , Células HEK293 , Humanos , Ratones , Ratones Endogámicos C57BL , Péptidos/farmacología , Interferencia de ARN , ARN Interferente Pequeño/antagonistas & inhibidores , Células Vero , Replicación Viral/efectos de los fármacos
5.
Nature ; 628(8007): 400-407, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38480882

RESUMEN

AIRE is an unconventional transcription factor that enhances the expression of thousands of genes in medullary thymic epithelial cells and promotes clonal deletion or phenotypic diversion of self-reactive T cells1-4. The biological logic of AIRE's target specificity remains largely unclear as, in contrast to many transcription factors, it does not bind to a particular DNA sequence motif. Here we implemented two orthogonal approaches to investigate AIRE's cis-regulatory mechanisms: construction of a convolutional neural network and leveraging natural genetic variation through analysis of F1 hybrid mice5. Both approaches nominated Z-DNA and NFE2-MAF as putative positive influences on AIRE's target choices. Genome-wide mapping studies revealed that Z-DNA-forming and NFE2L2-binding motifs were positively associated with the inherent ability of a gene's promoter to generate DNA double-stranded breaks, and promoters showing strong double-stranded break generation were more likely to enter a poised state with accessible chromatin and already-assembled transcriptional machinery. Consequently, AIRE preferentially targets genes with poised promoters. We propose a model in which Z-DNA anchors the AIRE-mediated transcriptional program by enhancing double-stranded break generation and promoter poising. Beyond resolving a long-standing mechanistic conundrum, these findings suggest routes for manipulating T cell tolerance.


Asunto(s)
Proteína AIRE , ADN de Forma Z , Tolerancia Inmunológica , Linfocitos T , Timo , Animales , Ratones , Proteína AIRE/metabolismo , Cromatina/genética , Cromatina/metabolismo , Roturas del ADN de Doble Cadena , ADN de Forma Z/química , ADN de Forma Z/genética , ADN de Forma Z/metabolismo , Células Epiteliales/metabolismo , Variación Genética , Redes Neurales de la Computación , Factor 2 Relacionado con NF-E2/metabolismo , Regiones Promotoras Genéticas , Linfocitos T/citología , Linfocitos T/inmunología , Timo/citología , Transcripción Genética , Femenino
6.
Nature ; 625(7994): 253-258, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38200292

RESUMEN

Neutron stars and stellar-mass black holes are the remnants of massive star explosions1. Most massive stars reside in close binary systems2, and the interplay between the companion star and the newly formed compact object has been theoretically explored3, but signatures for binarity or evidence for the formation of a compact object during a supernova explosion are still lacking. Here we report a stripped-envelope supernova, SN 2022jli, which shows 12.4-day periodic undulations during the declining light curve. Narrow Hα emission is detected in late-time spectra with concordant periodic velocity shifts, probably arising from hydrogen gas stripped from a companion and accreted onto the compact remnant. A new Fermi-LAT γ-ray source is temporally and positionally consistent with SN 2022jli. The observed properties of SN 2022jli, including periodic undulations in the optical light curve, coherent Hα emission shifting and evidence for association with a γ-ray source, point to the explosion of a massive star in a binary system leaving behind a bound compact remnant. Mass accretion from the companion star onto the compact object powers the light curve of the supernova and generates the γ-ray emission.

7.
Genome Res ; 33(3): 412-426, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36958795

RESUMEN

Tn5 transposon tagments double-stranded DNA and RNA/DNA hybrids to generate nucleic acids that are ready to be amplified for high-throughput sequencing. The nucleic acid substrates for the Tn5 transposon must be explored to increase the applications of Tn5. Here, we found that the Tn5 transposon can transpose oligos into the 5' end of single-stranded DNA longer than 140 nucleotides. Based on this property of Tn5, we developed a tagmentation-based and ligation-enabled single-stranded DNA sequencing method called TABLE-seq. Through a series of reaction temperature, time, and enzyme concentration tests, we applied TABLE-seq to strand-specific RNA sequencing, starting with as little as 30 pg of total RNA. Moreover, compared with traditional dUTP-based strand-specific RNA sequencing, this method detects more genes, has a higher strand specificity, and shows more evenly distributed reads across genes. Together, our results provide insights into the properties of Tn5 transposons and expand the applications of Tn5 in cutting-edge sequencing techniques.


Asunto(s)
ADN de Cadena Simple , ADN , ADN de Cadena Simple/genética , Secuencia de Bases , ARN/genética , Análisis de Secuencia de ARN , Elementos Transponibles de ADN/genética
8.
Nucleic Acids Res ; 52(10): 5549-5571, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38499486

RESUMEN

Complex organisms generate differential gene expression through the same set of DNA sequences in distinct cells. The communication between chromatin and RNA regulates cellular behavior in tissues. However, little is known about how chromatin, especially histone modifications, regulates RNA polyadenylation. In this study, we found that FUS was recruited to chromatin by H3K36me3 at gene bodies. The H3K36me3 recognition of FUS was mediated by the proline residues in the ZNF domain. After these proline residues were mutated or H3K36me3 was abolished, FUS dissociated from chromatin and bound more to RNA, resulting in an increase in polyadenylation sites far from stop codons genome-wide. A proline mutation corresponding to a mutation in amyotrophic lateral sclerosis contributed to the hyperactivation of mitochondria and hyperdifferentiation in mouse embryonic stem cells. These findings reveal that FUS is an H3K36me3 reader protein that links chromatin-mediated alternative polyadenylation to human disease.


Asunto(s)
Histonas , Poliadenilación , Proteína FUS de Unión a ARN , Animales , Humanos , Ratones , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Diferenciación Celular/genética , Cromatina/metabolismo , Cromatina/genética , Células HEK293 , Histonas/metabolismo , Histonas/genética , Mitocondrias/metabolismo , Mitocondrias/genética , Células Madre Embrionarias de Ratones , Mutación , Poliadenilación/genética , Proteína FUS de Unión a ARN/genética , Proteína FUS de Unión a ARN/metabolismo , Línea Celular , Dominios Proteicos
9.
Proc Natl Acad Sci U S A ; 120(24): e2220867120, 2023 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-37279265

RESUMEN

The mammalian cochlear epithelium undergoes substantial remodeling and maturation before the onset of hearing. However, very little is known about the transcriptional network governing cochlear late-stage maturation and particularly the differentiation of its lateral nonsensory region. Here, we establish ZBTB20 as an essential transcription factor required for cochlear terminal differentiation and maturation and hearing. ZBTB20 is abundantly expressed in the developing and mature cochlear nonsensory epithelial cells, with transient expression in immature hair cells and spiral ganglion neurons. Otocyst-specific deletion of Zbtb20 causes profound deafness with reduced endolymph potential in mice. The subtypes of cochlear epithelial cells are normally generated, but their postnatal development is arrested in the absence of ZBTB20, as manifested by an immature appearance of the organ of Corti, malformation of tectorial membrane (TM), a flattened spiral prominence (SP), and a lack of identifiable Boettcher cells. Furthermore, these defects are related with a failure in the terminal differentiation of the nonsensory epithelium covering the outer border Claudius cells, outer sulcus root cells, and SP epithelial cells. Transcriptome analysis shows that ZBTB20 regulates genes encoding for TM proteins in the greater epithelial ridge, and those preferentially expressed in root cells and SP epithelium. Our results point to ZBTB20 as an essential regulator for postnatal cochlear maturation and particularly for the terminal differentiation of cochlear lateral nonsensory domain.


Asunto(s)
Cóclea , Células Ciliadas Auditivas , Animales , Ratones , Cóclea/metabolismo , Células Ciliadas Auditivas/fisiología , Audición/fisiología , Mamíferos , Ganglio Espiral de la Cóclea , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
10.
Mol Biol Evol ; 41(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38401527

RESUMEN

Following invasion, insects can become adapted to conditions experienced in their invasive range, but there are few studies on the speed of adaptation and its genomic basis. Here, we examine a small insect pest, Thrips palmi, following its contemporary range expansion across a sharp climate gradient from the subtropics to temperate areas. We first found a geographically associated population genetic structure and inferred a stepping-stone dispersal pattern in this pest from the open fields of southern China to greenhouse environments of northern regions, with limited gene flow after colonization. In common garden experiments, both the field and greenhouse groups exhibited clinal patterns in thermal tolerance as measured by critical thermal maximum (CTmax) closely linked with latitude and temperature variables. A selection experiment reinforced the evolutionary potential of CTmax with an estimated h2 of 6.8% for the trait. We identified 3 inversions in the genome that were closely associated with CTmax, accounting for 49.9%, 19.6%, and 8.6% of the variance in CTmax among populations. Other genomic variations in CTmax outside the inversion region were specific to certain populations but functionally conserved. These findings highlight rapid adaptation to CTmax in both open field and greenhouse populations and reiterate the importance of inversions behaving as large-effect alleles in climate adaptation.


Asunto(s)
Adaptación Fisiológica , Inversión Cromosómica , Animales , Adaptación Fisiológica/genética , Clima , Temperatura , Insectos
11.
Plant Physiol ; 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38833579

RESUMEN

The asymmetrical distribution of auxin supports high intensity blue light (HBL)-mediated phototropism. Flavonoids, secondary metabolites induced by blue light and TRANSPARENT TESTA GLABRA1 (TTG1), alter auxin transport. However, the role of TTG1 in HBL-induced phototropism in Arabidopsis (Arabidopsis thaliana) remains unclear. We found that TTG1 regulates HBL-mediated phototropism. HBL-induced degradation of CRYPTOCHROME 1 (CRY1) was repressed in ttg1-1, and depletion of CRY1 rescued the phototropic defects of the ttg1-1 mutant. Moreover, overexpression of CRY1 in a cry1 mutant background led to phototropic defects in response to HBL. These results indicated that CRY1 is involved in the regulation of TTG1-mediated phototropism in response to HBL. Further investigation showed that TTG1 physically interacts with CRY1 via its N-terminus and that the added TTG1 promotes the dimerization of CRY1. The interaction between TTG1 and CRY1 may promote HBL-mediated degradation of CRY1. TTG1 also physically interacted with blue light inhibitor of cryptochrome 1 (BIC1) and Light-Response Bric-a-Brack/Tramtrack/Broad 2 (LRB2), and these interactions either inhibited or promoted their interaction with CRY1. Exogenous gibberellins (GA) and auxins, two key plant hormones that crosstalk with CRY1, may confer the recovery of phototropic defects in the ttg1-1 mutant and CRY1-overexpressing plants. Our results revealed that TTG1 participates in the regulation of HBL-induced phototropism by modulating CRY1 levels, which are coordinated with GA or IAA signaling.

12.
Exp Cell Res ; 435(2): 113947, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38301989

RESUMEN

Cancer-associated fibroblasts (CAFs) are the main components in the tumor microenvironment. Tumors activate fibroblasts from quiescent state into activated state by secreting cytokines, and activated CAFs may in turn promote tumor progression and metastasis. Therefore, studies targeting CAFs could enrich the therapeutic options for tumor treatment. In this study, we demonstrate that the content of lipid droplets and the expression of autophagosomes were higher in CAFs than in peri-tumor fibroblasts (PTFs), which was inhibited by 5-(tetradecyloxy)-2-furoic acid(TOFA). The expression of CD36 in CAFs was higher than that in PTFs at both mRNA and protein levels. Inhibition of CD36 activity using either the CD36 inhibitor SSO or siRNA had a significant negative impact on the proliferation and migration abilities of CAFs, which was associated with reduced levels of relevant activated genes (α-SMA, FAP, Vimentin) and cytokines (IL-6, TGF-ß and VEGF-α). SSO also inhibited HCC growth and tumorigenesis in nude mice orthotopically implanted with CAFs and HCC cells. Our data further show that CD36+CAFs affected the expression of PD-1 in CTLs leading to CTL exhaustion, and that patients with high CD36 expression in CAFs were correlated with shorter overall survival (OS). Together, our data demonstrate that CAFs were active in lipid metabolism with increased lipid content and lipophagy activity. CD36 may play a key role in the regulation of the biological behaviors of CAFs, which may influence the proliferation and migration of tumor cells by reprograming the lipid metabolism in tumor cells. Thus, CD36 could be an effective therapeutic target for the treatment of HCC.


Asunto(s)
Fibroblastos Asociados al Cáncer , Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Ratones , Humanos , Carcinoma Hepatocelular/patología , Fibroblastos Asociados al Cáncer/patología , Neoplasias Hepáticas/patología , Ratones Desnudos , Reprogramación Metabólica , Línea Celular Tumoral , Fibroblastos/metabolismo , Citocinas/metabolismo , Microambiente Tumoral , Proliferación Celular
13.
Mol Ther ; 32(1): 204-217, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37952086

RESUMEN

Inner ear hair cells detect sound vibration through the deflection of mechanosensory stereocilia. Cytoplasmic protein TPRN has been shown to localize at the taper region of the stereocilia, and mutations in TPRN cause hereditary hearing loss through an unknown mechanism. Here, using biochemistry and dual stimulated emission depletion microscopy imaging, we show that the TPRN, together with its binding proteins CLIC5 and PTPRQ, forms concentric rings in the taper region of stereocilia. The disruption of TPRN rings, triggered by the competitive inhibition of the interaction of TPRN and CLIC5 or exogenous TPRN overexpression, leads to stereocilia degeneration and severe hearing loss. Most importantly, restoration of the TPRN rings can rescue the damaged auditory function of Tprn knockout mice by exogenously expressing TPRN at an appropriate level in HCs via promoter recombinant adeno-associated virus (AAV). In summary, our results reveal highly structured TPRN rings near the taper region of stereocilia that are crucial for stereocilia function and hearing. Also, TPRN ring restoration in stereocilia by AAV-Tprn effectively repairs damaged hearing, which lays the foundation for the clinical application of AAV-mediated gene therapy in patients with TPRN mutation.


Asunto(s)
Sordera , Pérdida Auditiva , Animales , Humanos , Ratones , Sordera/genética , Audición/genética , Pérdida Auditiva/genética , Pérdida Auditiva/terapia , Ratones Noqueados , Proteínas/metabolismo , Proteínas Tirosina Fosfatasas Clase 3 Similares a Receptores/metabolismo , Estereocilios/metabolismo
14.
J Lipid Res ; 65(2): 100499, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38218337

RESUMEN

Ferroptosis is a novel cell death mechanism that is mediated by iron-dependent lipid peroxidation. It may be involved in atherosclerosis development. Products of phospholipid oxidation play a key role in atherosclerosis. 1-palmitoyl-2-glutaroyl-sn-glycero-3-phosphocholine (PGPC) is a phospholipid oxidation product present in atherosclerotic lesions. It remains unclear whether PGPC causes atherosclerosis by inducing endothelial cell ferroptosis. In this study, human umbilical vein endothelial cells (HUVECs) were treated with PGPC. Intracellular levels of ferrous iron, lipid peroxidation, superoxide anions (O2•-), and glutathione were detected, and expression of fatty acid binding protein-3 (FABP3), glutathione peroxidase 4 (GPX4), and CD36 were measured. Additionally, the mitochondrial membrane potential (MMP) was determined. Aortas from C57BL6 mice were isolated for vasodilation testing. Results showed that PGPC increased ferrous iron levels, the production of lipid peroxidation and O2•-, and FABP3 expression. However, PGPC inhibited the expression of GPX4 and glutathione production and destroyed normal MMP. These effects were also blocked by ferrostatin-1, an inhibitor of ferroptosis. FABP3 silencing significantly reversed the effect of PGPC. Furthermore, PGPC stimulated CD36 expression. Conversely, CD36 silencing reversed the effects of PGPC, including PGPC-induced FABP3 expression. Importantly, E06, a direct inhibitor of the oxidized 1-palmitoyl-2-arachidonoyl-phosphatidylcholine IgM natural antibody, inhibited the effects of PGPC. Finally, PGPC impaired endothelium-dependent vasodilation, ferrostatin-1 or FABP3 inhibitors inhibited this impairment. Our data demonstrate that PGPC impairs endothelial function by inducing endothelial cell ferroptosis through the CD36 receptor to increase FABP3 expression. Our findings provide new insights into the mechanisms of atherosclerosis and a therapeutic target for atherosclerosis.


Asunto(s)
Aterosclerosis , Ciclohexilaminas , Ferroptosis , Fenilendiaminas , Animales , Ratones , Humanos , Fosfolípidos , Fosforilcolina , Éteres Fosfolípidos/metabolismo , Éteres Fosfolípidos/farmacología , Ratones Endogámicos C57BL , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Endotelio/metabolismo , Glutatión/metabolismo , Hierro/metabolismo , Proteína 3 de Unión a Ácidos Grasos
15.
Br J Cancer ; 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38824222

RESUMEN

BACKGROUND: Disorder of cell cycle represents as a major driver of hepatocarcinogenesis and constitutes an attractive therapeutic target. However, identifying key genes that respond to cell cycle-dependent treatments still facing critical challenges in hepatocellular carcinoma (HCC). Increasing evidence indicates that dynein light chain 1 (DYNLL1) is closely related to cell cycle progression and plays a critical role in tumorigenesis. In this study, we explored the role of DYNLL1 in the regulation of cell cycle progression in HCC. METHODS: We analysed clinical specimens to assess the expression and predictive value of DYNLL1 in HCC. The oncogenic role of DYNLL1 was determined by gain or loss-of-function experiments in vitro, and xenograft tumour, liver orthotopic, and DEN/CCl4-induced mouse models in vivo. Mass spectrometry analysis, RNA sequencing, co-immunoprecipitation assays, and forward and reverse experiments were performed to clarify the mechanism by which DYNLL1 activates the interleukin-2 enhancer-binding factor 2 (ILF2)/CDK4 signalling axis. Finally, the sensitivity of HCC cells to palbociclib and sorafenib was assessed by apoptosis, cell counting kit-8, and colony formation assays in vitro, and xenograft tumour models and liver orthotopic models in vivo. RESULTS: DYNLL1 was significantly higher in HCC tissues than that in normal liver tissues and closely related to the clinicopathological features and prognosis of patients with HCC. Importantly, DYNLL1 was identified as a novel hepatocarcinogenesis gene from both in vitro and in vivo evidence. Mechanistically, DYNLL1 could interact with ILF2 and facilitate the expression of ILF2, then ILF2 could interact with CDK4 mRNA and delay its degradation, which in turn activates downstream G1/S cell cycle target genes CDK4. Furthermore, palbociclib, a selective CDK4/6 inhibitor, represents as a promising therapeutic strategy for DYNLL1-overexpressed HCC, alone or particularly in combination with sorafenib. CONCLUSIONS: Our work uncovers a novel function of DYNLL1 in orchestrating cell cycle to promote HCC development and suggests a potential synergy of CDK4/6 inhibitor and sorafenib for the treatment of HCC patients, especially those with increased DYNLL1.

16.
J Hepatol ; 81(1): 135-148, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38460791

RESUMEN

BACKGROUND & AIMS: NOTCH signaling in liver sinusoidal endothelial cells (LSECs) regulates liver fibrosis, a pathological feature of chronic liver diseases. POFUT1 is an essential regulator of NOTCH signaling. Here, we investigated the role of LSEC-expressed POFUT1 in liver fibrosis. METHODS: Endothelial-specific Pofut1 knockout mice were generated and experimental liver fibrosis was induced by chronic carbon tetrachloride exposure or common bile duct ligation. Liver samples were assessed by ELISA, histology, electron microscopy, immunostaining and RNA in situ hybridization. LSECs and hepatic stellate cells (HSCs) were isolated for gene expression analysis by RNA sequencing, qPCR, and western blotting. Signaling crosstalk between LSECs and HSCs was investigated by treating HSCs with supernatant from LSEC cultures. Liver single-cell RNA sequencing datasets from patients with cirrhosis and healthy individuals were analyzed to evaluate the clinical relevance of gene expression changes observed in mouse studies. RESULTS: POFUT1 loss promoted injury-induced LSEC capillarization and HSC activation, leading to aggravated liver fibrosis. RNA sequencing analysis revealed that POFUT1 deficiency upregulated fibrinogen expression in LSECs. Consistently, fibrinogen was elevated in LSECs of patients with cirrhosis. HSCs treated with supernatant from LSECs of Pofut1 null mice showed exacerbated activation compared to those treated with supernatant from control LSECs, and this effect was attenuated by knockdown of fibrinogen or by pharmacological inhibition of fibrinogen receptor signaling, altogether suggesting that LSEC-derived fibrinogen induced the activation of HSCs. Mechanistically, POFUT1 loss augmented fibrinogen expression by enhancing NOTCH/HES1/STAT3 signaling. CONCLUSIONS: Endothelial POFUT1 prevents injury-induced liver fibrosis by repressing the expression of fibrinogen, which functions as a profibrotic paracrine signal to activate HSCs. Therapies targeting the POFUT1/fibrinogen axis offer a promising strategy for the prevention and treatment of fibrotic liver diseases. IMPACT AND IMPLICATIONS: Paracrine signals produced by liver vasculature play a major role in the development of liver fibrosis, which is a pathological hallmark of most liver diseases. Identifying those paracrine signals is clinically relevant in that they may serve as therapeutic targets. In this study, we discovered that genetic deletion of Pofut1 aggravated experimental liver fibrosis in mouse models. Moreover, fibrinogen was identified as a downstream target repressed by Pofut1 in liver endothelial cells and functioned as a novel paracrine signal that drove liver fibrosis. In addition, fibrinogen was found to be relevant to cirrhosis and may serve as a potential therapeutic target for this devastating human disease.


Asunto(s)
Células Endoteliales , Fibrinógeno , Células Estrelladas Hepáticas , Cirrosis Hepática , Ratones Noqueados , Animales , Ratones , Fibrinógeno/metabolismo , Fibrinógeno/biosíntesis , Fibrinógeno/genética , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Cirrosis Hepática/genética , Células Estrelladas Hepáticas/metabolismo , Células Endoteliales/metabolismo , Humanos , Transducción de Señal , Masculino , Tetracloruro de Carbono/toxicidad , Tetracloruro de Carbono/efectos adversos , Hígado/metabolismo , Hígado/patología , Receptores Notch/metabolismo , Receptores Notch/fisiología , Modelos Animales de Enfermedad
17.
J Gene Med ; 26(5): e3691, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38757222

RESUMEN

BACKGROUND: Pancreatic cancer is characterized by metabolic dysregulation and unique immunological profiles. Nevertheless, the comprehensive understanding of immune and metabolic dysregulation of pancreatic cancer remains unclear. In the present study, we aimed to investigate the causal relationship of circulating immune cells and pancreatic cancer and identify the blood metabolites as potential mediators. METHODS: The exposure and outcome genome-wide association studies (GWAS) data used in the present study were obtained from the GWAS open-access database (https://gwas.mrcieu.ac.uk). The study used 731 circulating immune cell features, 1400 types of blood metabolites and pancreatic cancer from GWAS. We then performed bidirectional Mendelian randomization (MR) analyses to explore the causal relationships between the circulating immune cells and pancreatic cancer, and two-step MR to discover potential mediating blood metabolites in this process. All statistical analyses were performed in R software. The STROBE-MR (i.e. Strengthening the Reporting of Observational Studies in Epidemiology using Mendelian Randomization) checklist for the reporting of MR studies was also used. RESULTS: MR analysis identified seven types of circulating immune cells causally associated with pancreatic cancer. Furthermore, there was no strong evidence that genetically predicted pancreatic cancer had an effect on these seven types of circulating immune cells. Further two-step MR analysis found 10 types of blood metabolites were causally associated with pancreatic cancer and the associations between circulating CD39+CD8+ T cells and pancreatic cancer were mediated by blood orotates with proportions of 5.18% (p = 0.016). CONCLUSIONS: The present study provides evidence supporting the causal relationships between various circulating immune cells, especially CD39+CD8+ T cells, and pancreatic cancer, with a potential effect mediated by blood orotates. Further research is needed on additional risk factors as potential mediators and establish a comprehensive immunity-metabolism network in pancreatic cancer.


Asunto(s)
Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/inmunología , Polimorfismo de Nucleótido Simple , Predisposición Genética a la Enfermedad , Metaboloma
18.
Small ; : e2310940, 2024 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-38700049

RESUMEN

Graphene supported electrocatalysts have demonstrated remarkable catalytic performance for oxygen reduction reaction (ORR). However, their durability and cycling performance are greatly limited by Oswald ripening of platinum (Pt) and graphene support corrosion. Moreover, comprehensive studies on the mechanisms of catalysts degradation under 0.6-1.6 V versus RHE (Reversible Hydrogen Electrode) is still lacking. Herein, degradation mechanisms triggered by different defects on graphene supports are investigated by two cycling protocols. In the start-up/shutdown cycling (1.0-1.6 V vs. RHE), carbon oxidation reaction (COR) leads to shedding or swarm-like aggregation of Pt nanoparticles (NPs). Theoretical simulation results show that the expansion of vacancy defects promotes reaction kinetics of the decisive step in COR, reducing its reaction overpotential. While under the load cycling (0.6-1.0 V vs. RHE), oxygen containing defects lead to an elevated content of Pt in its oxidation state which intensifies Oswald ripening of Pt. The presence of vacancy defects can enhance the transfer of electrons from graphene to the Pt surface, reducing the d-band center of Pt and making it more difficult for the oxidation state of platinum to form in the cycling. This work will provide comprehensive understanding on Pt/Graphene catalysts degradation mechanisms.

19.
Int J Obes (Lond) ; 48(3): 302-314, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38086902

RESUMEN

Overweight and obesity have emerged as global health issues among children and adolescents. Restrictions related to the COVID-19 pandemic have aggravated the threat of paediatric obesity due to the prevalent reduction in physical activity (PA) in children and adolescents. However, this has also created an opportunity for healthcare professionals to explore new strategies to address this persistent problem. A systematically conducted scoping review was performed on 15 online databases to summarise and analyse the design, efficacy, and feasibility of PA-based weight management interventions for children and adolescents during the pandemic. Finally, we reviewed 23 eligible studies that were published between 2021 and 2023. The included interventions were presented to 1938 children and adolescents and 355 parents using a virtual or virtually blended face-to-face approach during the pandemic. The intervention design included a basic PA programme with three optional components (nutritional education, sociopsychological counselling, and medication consultations). Implementation generally resulted in favourable changes in body mass index (BMI) and/or body size or composition (primary outcomes), as well as health behaviours, physical health or fitness, and individual well-being (secondary outcomes). A longer duration of exposure to the intervention, female sex, and older age were associated with a higher efficacy of the included interventions. Moreover, the interventions showed high feasibility, with medium-high participant attendance, high acceptance/satisfaction in both children and adolescents and their parents and teachers, and strong participant engagement. This may be related to the high accessibility of health information, timely social support, and enhanced self-efficacy. In conclusion, both the virtual and blended delivery of well-planned weight management interventions during the pandemic show promise for the treatment and control of paediatric obesity. The lessons learned from the pandemic may help improve the design of future interventions and inform the proper integration of new technologies that have emerged in the post-pandemic world.


Asunto(s)
COVID-19 , Manejo de la Obesidad , Obesidad Infantil , Niño , Humanos , Femenino , Adolescente , Obesidad Infantil/epidemiología , Obesidad Infantil/prevención & control , Pandemias/prevención & control , COVID-19/epidemiología , Ejercicio Físico
20.
J Transl Med ; 22(1): 170, 2024 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-38368381

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is characterized by aggressive progression and elevated mortality rates. This study aimed to investigate the regulatory effects of RBBP7 on HCC pathogenesis and the underlying mechanisms. METHODS: The expression and clinical feature of RBBP7 were evaluated using bioinformatics analysis and the assessment of clinical HCC samples. CCK8 and colony formation were employed to estimate cell proliferation function of RBBP7. Aerobic glycolysis levels of RBBP7 were evaluated by measuring ATP levels, lactic acid production, glucose uptake capacity, and the expression of relevant enzymes (PFKM, PKM2, and LDHA). The phosphorylation levels in PI3K/AKT signaling were measured by western blotting. The regulatory effect of transcription factors of specificity protein 1 (SP1) on RBBP7 mRNA expression was confirmed in dual-luciferase reporter assays and chromatin immunoprecipitation experiments. The proliferation- and glycolysis-associated proteins were assessed using immunofluorescence staining in vivo. RESULTS: We found that RBBP7 is expressed at high levels in HCC and predicts poor survival. Functional assays showed that RBBP7 promoted HCC proliferation and glycolysis. Mechanistically, it was demonstrated that RBBP7 activates the PI3K/AKT pathway, a crucial pathway in glycolysis, contributing to the progression of HCC. The outcomes of the dual-luciferase assay further confirmed that SP1 is capable of activating the promoter of RBBP7. CONCLUSIONS: RBBP7, which is up-regulated by SP1, promotes HCC cell proliferation and glycolysis through the PI3K/AKT pathway. The findings of this study suggest that RBBP7 is a potential biomarker for HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/patología , Luciferasas/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteína 7 de Unión a Retinoblastoma/genética , Proteína 7 de Unión a Retinoblastoma/metabolismo
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