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1.
Cell ; 178(3): 552-566.e20, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31327526

RESUMO

Antibacterial autophagy (xenophagy) is an important host defense, but how it is initiated is unclear. Here, we performed a bacterial transposon screen and identified a T3SS effector SopF that potently blocked Salmonella autophagy. SopF was a general xenophagy inhibitor without affecting canonical autophagy. S. Typhimurium ΔsopF resembled S. flexneri ΔvirAΔicsB with the majority of intracellular bacteria targeted by autophagy, permitting a CRISPR screen that identified host V-ATPase as an essential factor. Upon bacteria-caused vacuolar damage, the V-ATPase recruited ATG16L1 onto bacteria-containing vacuole, which was blocked by SopF. Mammalian ATG16L1 bears a WD40 domain required for interacting with the V-ATPase. Inhibiting autophagy by SopF promoted S. Typhimurium proliferation in vivo. SopF targeted Gln124 of ATP6V0C in the V-ATPase for ADP-ribosylation. Mutation of Gln124 also blocked xenophagy, but not canonical autophagy. Thus, the discovery of SopF reveals the V-ATPase-ATG16L1 axis that critically mediates autophagic recognition of intracellular pathogen.


Assuntos
Proteínas Relacionadas à Autofagia/metabolismo , Proteínas de Bactérias/genética , Macroautofagia , Salmonella/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Fatores de Virulência/genética , ADP-Ribosilação , Proteínas Relacionadas à Autofagia/deficiência , Proteínas Relacionadas à Autofagia/genética , Proteínas de Bactérias/metabolismo , Sistemas CRISPR-Cas/genética , Edição de Genes , Células HeLa , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Ligação Proteica , Salmonella/patogenicidade , Sistemas de Secreção Tipo III/metabolismo , ATPases Vacuolares Próton-Translocadoras/genética , Fatores de Virulência/metabolismo
2.
Nat Immunol ; 22(9): 1107-1117, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34385713

RESUMO

The linkage between neutrophil death and the development of autoimmunity has not been thoroughly explored. Here, we show that neutrophils from either lupus-prone mice or patients with systemic lupus erythematosus (SLE) undergo ferroptosis. Mechanistically, autoantibodies and interferon-α present in the serum induce neutrophil ferroptosis through enhanced binding of the transcriptional repressor CREMα to the glutathione peroxidase 4 (Gpx4, the key ferroptosis regulator) promoter, which leads to suppressed expression of Gpx4 and subsequent elevation of lipid-reactive oxygen species. Moreover, the findings that mice with neutrophil-specific Gpx4 haploinsufficiency recapitulate key clinical features of human SLE, including autoantibodies, neutropenia, skin lesions and proteinuria, and that the treatment with a specific ferroptosis inhibitor significantly ameliorates disease severity in lupus-prone mice reveal the role of neutrophil ferroptosis in lupus pathogenesis. Together, our data demonstrate that neutrophil ferroptosis is an important driver of neutropenia in SLE and heavily contributes to disease manifestations.


Assuntos
Ferroptose/fisiologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Neutropenia/patologia , Neutrófilos/imunologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Animais , Autoanticorpos/imunologia , Autoimunidade/imunologia , Modulador de Elemento de Resposta do AMP Cíclico/metabolismo , Humanos , Interferon-alfa/imunologia , Camundongos , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/genética , Regiões Promotoras Genéticas/genética , Espécies Reativas de Oxigênio/metabolismo
3.
Nature ; 599(7884): 290-295, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34671164

RESUMO

Mouse caspase-11 and human caspase-4 and caspase-5 recognize cytosolic lipopolysaccharide (LPS) to induce pyroptosis by cleaving the pore-forming protein GSDMD1-5. This non-canonical inflammasome defends against Gram-negative bacteria6,7. Shigella flexneri, which causes bacillary dysentery, lives freely within the host cytosol where these caspases reside. However, the role of caspase-11-mediated pyroptosis in S. flexneri infection is unknown. Here we show that caspase-11 did not protect mice from S. flexneri infection, in contrast to infection with another cytosolic bacterium, Burkholderia thailandensis8. S. flexneri evaded pyroptosis mediated by caspase-11 or caspase 4 (hereafter referred to as caspase-11/4) using a type III secretion system (T3SS) effector, OspC3. OspC3, but not its paralogues OspC1 and 2, covalently modified caspase-11/4; although it used the NAD+ donor, this modification was not ADP-ribosylation. Biochemical dissections uncovered an ADP-riboxanation modification on Arg314 and Arg310 in caspase-4 and caspase-11, respectively. The enzymatic activity was shared by OspC1 and 2, whose ankyrin-repeat domains, unlike that of OspC3, could not recognize caspase-11/4. ADP-riboxanation of the arginine blocked autoprocessing of caspase-4/11 as well as their recognition and cleavage of GSDMD. ADP-riboxanation of caspase-11 paralysed pyroptosis-mediated defence in Shigella-infected mice and mutation of ospC3 stimulated caspase-11- and GSDMD-dependent anti-Shigella humoral immunity, generating a vaccine-like protective effect. Our study establishes ADP-riboxanation of arginine as a bacterial virulence mechanism that prevents LPS-induced pyroptosis.


Assuntos
Adenosina Difosfato Ribose/metabolismo , Arginina/metabolismo , Proteínas de Bactérias/metabolismo , Caspases Iniciadoras/metabolismo , Evasão da Resposta Imune , Piroptose , Shigella flexneri/patogenicidade , Difosfato de Adenosina/metabolismo , Animais , Disenteria Bacilar/imunologia , Disenteria Bacilar/microbiologia , Feminino , Imunidade Humoral , Inflamassomos/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , NAD/metabolismo , Piroptose/efeitos dos fármacos , Vacinas contra Shigella , Shigella flexneri/imunologia , Virulência
4.
Proc Natl Acad Sci U S A ; 120(50): e2309472120, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38060560

RESUMO

Ionizable lipid nanoparticles (LNPs) pivotal to the success of COVID-19 mRNA (messenger RNA) vaccines hold substantial promise for expanding the landscape of mRNA-based therapies. Nevertheless, the risk of mRNA delivery to off-target tissues highlights the necessity for LNPs with enhanced tissue selectivity. The intricate nature of biological systems and inadequate knowledge of lipid structure-activity relationships emphasize the significance of high-throughput methods to produce chemically diverse lipid libraries for mRNA delivery screening. Here, we introduce a streamlined approach for the rapid design and synthesis of combinatorial libraries of biodegradable ionizable lipids. This led to the identification of iso-A11B5C1, an ionizable lipid uniquely apt for muscle-specific mRNA delivery. It manifested high transfection efficiencies in muscle tissues, while significantly diminishing off-targeting in organs like the liver and spleen. Moreover, iso-A11B5C1 also exhibited reduced mRNA transfection potency in lymph nodes and antigen-presenting cells, prompting investigation into the influence of direct immune cell transfection via LNPs on mRNA vaccine effectiveness. In comparison with SM-102, while iso-A11B5C1's limited immune transfection attenuated its ability to elicit humoral immunity, it remained highly effective in triggering cellular immune responses after intramuscular administration, which is further corroborated by its strong therapeutic performance as cancer vaccine in a melanoma model. Collectively, our study not only enriches the high-throughput toolkit for generating tissue-specific ionizable lipids but also encourages a reassessment of prevailing paradigms in mRNA vaccine design. This study encourages rethinking of mRNA vaccine design principles, suggesting that achieving high immune cell transfection might not be the sole criterion for developing effective mRNA vaccines.


Assuntos
Nanopartículas , Vacinas de mRNA , Músculos , Lipossomos , Transfecção
5.
Brief Bioinform ; 24(3)2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-36961325

RESUMO

Exosomes cargo tumour-characterized biomolecules secreted from cancer cells and play a pivotal role in tumorigenesis and cancer progression, thus providing their potential for non-invasive cancer monitoring. Since cancer cell-derived exosomes are often mixed with those from healthy cells in liquid biopsy of tumour patients, accurately measuring the purity of tumour cell-derived exosomes is not only critical for the early detection but also essential for unbiased identification of diagnosis biomarkers. Here, we propose 'ExosomePurity', a tumour purity deconvolution model to estimate tumour purity in serum exosomes of cancer patients based on microribonucleic acid (miRNA)-Seq data. We first identify the differently expressed miRNAs as signature to distinguish cancer cell- from healthy cell-derived exosomes. Then, the deconvolution model was developed to estimate the proportions of cancer exosomes and normal exosomes in serum. The purity predicted by the model shows high correlation with actual purity in simulated data and actual data. Moreover, the model is robust under the different levels of noise background. The tumour purity was also used to correct differential expressed gene analysis. ExosomePurity empowers the research community to study non-invasive early diagnosis and to track cancer progression in cancers more efficiently. It is implemented in R and is freely available from GitHub (https://github.com/WangHYLab/ExosomePurity).


Assuntos
Exossomos , MicroRNAs , Neoplasias , Humanos , Exossomos/genética , Biomarcadores Tumorais/genética , MicroRNAs/genética , Neoplasias/genética , Biópsia Líquida
6.
Annu Rev Microbiol ; 74: 221-245, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32660389

RESUMO

Microbial pathogens have evolved complex mechanisms to interface with host cells in order to evade host defenses and replicate. However, mammalian innate immune receptors detect the presence of molecules unique to the microbial world or sense the activity of virulence factors, activating antimicrobial and inflammatory pathways. We focus on how studies of the major virulence factor of one group of microbial pathogens, the type III secretion system (T3SS) of human pathogenic Yersinia, have shed light on these important innate immune responses. Yersinia are largely extracellular pathogens, yet they insert T3SS cargo into target host cells that modulate the activity of cytosolic innate immune receptors. This review covers both the host pathways that detect the Yersinia T3SS and the effector proteins used by Yersinia to manipulate innate immune signaling.


Assuntos
Citosol/imunologia , Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata , Sistemas de Secreção Tipo III/imunologia , Yersinia/imunologia , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Citosol/microbiologia , Humanos , Inflamassomos , Piroptose , Transdução de Sinais , Fatores de Virulência/metabolismo , Yersinia/metabolismo , Yersinia/patogenicidade
7.
FASEB J ; 38(13): e23760, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38924449

RESUMO

Hyponatremia is the most common disorder of electrolyte imbalances. It is necessary to develop new type of diuretics to treat hyponatremia without losing electrolytes. Urea transporters (UT) play an important role in the urine concentrating process and have been proved as a novel diuretic target. In this study, rat and mouse syndromes of inappropriate antidiuretic hormone secretion (SIADH) models were constructed and analyzed to determine if UTs are a promising drug target for treating hyponatremia. Experimental results showed that 100 mg/kg UT inhibitor 25a significantly increased serum osmolality (from 249.83 ± 5.95 to 294.33 ± 3.90 mOsm/kg) and serum sodium (from 114 ± 2.07 to 136.67 ± 3.82 mmol/L) respectively in hyponatremia rats by diuresis. Serum chemical examination showed that 25a neither caused another electrolyte imbalance nor influenced the lipid metabolism. Using UT-A1 and UT-B knockout mouse SIADH model, it was found that serum osmolality and serum sodium were lowered much less in UT-A1 knockout mice than in UT-B knockout mice, which suggest UT-A1 is a better therapeutic target than UT-B to treat hyponatremia. This study provides a proof of concept that UT-A1 is a diuretic target for SIADH-induced hyponatremia and UT-A1 inhibitors might be developed into new diuretics to treat hyponatremia.


Assuntos
Hiponatremia , Síndrome de Secreção Inadequada de HAD , Proteínas de Membrana Transportadoras , Camundongos Knockout , Transportadores de Ureia , Animais , Masculino , Camundongos , Ratos , Modelos Animais de Doenças , Diuréticos/farmacologia , Hiponatremia/tratamento farmacológico , Hiponatremia/metabolismo , Síndrome de Secreção Inadequada de HAD/tratamento farmacológico , Síndrome de Secreção Inadequada de HAD/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Camundongos Endogâmicos C57BL , Concentração Osmolar , Ratos Sprague-Dawley , Sódio/metabolismo
8.
Nano Lett ; 24(1): 43-50, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-37930062

RESUMO

The defect emission from h-BN at 1.55 eV is interesting as it enables optical readout of spins. It is necessary to identify the nature of the relevant point defects for its controlled introduction. However, it is challenging to engineer point defects in h-BN without changing the local atomic structure. Here, we controllably introduce boron vacancies in h-BN using an ultrahigh spatial resolution and low-energy He+ ion beam. By optimizing the He+ ion irradiation conditions, we control the quantity and location of defects spatially and along the depth of h-BN to achieve a robust photoluminescence emission at 1.55 eV from 10 K to room temperature. We show that as-generated defects activate an additional Raman mode at 1295 cm-1. Electron energy loss spectroscopy confirms introduction of boron vacancies without modification of the local h-BN crystal structure. Our results provide a deterministic strategy to create scalable boron vacancy emitters in h-BN for quantum photonics.

9.
Biophys J ; 123(12): 1690-1704, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38751113

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease characterized by dementia and memory loss in the elderly population. The amyloid-ß peptide (Aß) is one of the main pathogenic factors in AD and is known to cause damage to neuronal cellular membranes. There is no cure currently available for AD, and new approaches, including preventive strategies, are highly desirable. In this work, we explore the possibility of protecting neuronal membranes from amyloid-induced damage with naturally existing sugar trehalose. Trehalose has been shown to protect plant cellular membranes in extreme conditions and modify Aß misfolding. We hypothesize that trehalose can protect the neuronal membrane from amyloid toxicity. In this work, we studied the protective effect of trehalose against Aß1-42-induced damage in model lipid membranes (DPPC/POPC/cholesterol) using atomic force microscopy and black lipid membrane electrophysiology. Our results demonstrate that Aß1-42 damaged membranes and led to ionic current leakage across these membranes due to the formation of various defects and pores. The presence of trehalose reduced the ion current across membranes caused by Aß1-42 peptide damage, thus efficiently protecting the membranes. These findings suggest that the trehalose sugar can potentially be useful in protecting neuronal membranes against amyloid toxicity in AD.


Assuntos
Peptídeos beta-Amiloides , Bicamadas Lipídicas , Fragmentos de Peptídeos , Trealose , Trealose/farmacologia , Trealose/metabolismo , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/química , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/química , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Membrana Celular/metabolismo , Membrana Celular/efeitos dos fármacos , Fenômenos Eletrofisiológicos/efeitos dos fármacos
10.
Genes Immun ; 25(1): 66-81, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38246974

RESUMO

Interferon-γ (IFN-γ) is an important cytokine in tissue homeostasis and immune response, while studies about it in antibody-mediated rejection (ABMR) are very limited. This study aims to comprehensively elucidate the role of IFN-γ in ABMR after renal transplantation. In six renal transplantation cohorts, the IFN-γ responses (IFNGR) biological process was consistently top up-regulated in ABMR compared to stable renal function or even T cell-mediated rejection in both allografts and peripheral blood. According to single-cell analysis, IFNGR levels were found to be broadly elevated in most cell types in allografts and peripheral blood with ABMR. In allografts with ABMR, M1 macrophages had the highest IFNGR levels and were heavily infiltrated, while kidney resident M2 macrophages were nearly absent. In peripheral blood, CD14+ monocytes had the top IFNGR level and were significantly increased in ABMR. Immunofluorescence assay showed that levels of IFN-γ and M1 macrophages were sharply elevated in allografts with ABMR than non-rejection. Importantly, the IFNGR level in allografts was identified as a strong risk factor for long-term renal graft survival. Together, this study systematically analyzed multi-omics from thirteen independent cohorts and identified IFN-γ and IFNGR as determinants of ABMR and clinical outcomes in patients after renal transplantation.


Assuntos
Transplante de Rim , Humanos , Anticorpos , Rejeição de Enxerto/etiologia , Interferon gama , Fatores de Risco
11.
Am J Physiol Cell Physiol ; 327(2): C254-C269, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38798269

RESUMO

The podocyte cytoskeleton determines the stability of podocyte structure and function, and their imbalance plays a pathogenic role in podocyte diseases. However, the underlying mechanism of podocyte cytoskeleton damage is not fully understood. Here, we investigate the specific role of cuproptosis in inducing podocyte cytoskeleton injury. In in vitro and in vivo studies, exposure to high levels of copper and adriamycin (ADR) caused significant increases in copper concentration in intracellular and renal tissue. Moreover, excessive accumulation of copper induced cuproptosis, resulting in the destruction of the podocyte cytoskeleton. However, inhibition of copper accumulation to reduce cuproptosis also significantly alleviated the damage of podocyte cytoskeleton. In addition, inhibition of cuproptosis mitigated ADR-induced mitochondrial damage as well as the production of reactive oxygen species and depolarization of mitochondrial membrane potential, and restored adenosine triphosphate (ATP) synthesis. Among the transcriptome sequencing data, the difference of CXCL5 (C-X-C motif chemokine ligand 5) was the most significant. Both high copper and ADR exposure can cause upregulation of CXCL5, and CXCL5 deletion inhibits the occurrence of cuproptosis, thereby alleviating the podocyte cytoskeleton damage. This suggests that CXCL5 may act upstream of cuproptosis that mediates podocyte cytoskeleton damage. In conclusion, cuproptosis induced by excessive copper accumulation may induce podocyte cytoskeleton damage by promoting mitochondrial dysfunction, thereby causing podocyte injury. This indicates that cuproptosis plays an important role in the pathogenesis of podocyte injury and provides a basis for seeking potential targets for the treatment of chronic kidney disease.NEW & NOTEWORTHY Cuproptosis induced by excessive copper accumulation leads to podocyte cytoskeleton damage by promoting mitochondrial dysfunction, and CXCL5 acts as an upstream signal mediating the occurrence of cuproptosis.


Assuntos
Cobre , Citoesqueleto , Podócitos , Insuficiência Renal Crônica , Podócitos/metabolismo , Podócitos/patologia , Citoesqueleto/metabolismo , Citoesqueleto/patologia , Animais , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/genética , Cobre/metabolismo , Cobre/toxicidade , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Masculino , Doxorrubicina/toxicidade , Camundongos Endogâmicos C57BL , Potencial da Membrana Mitocondrial , Humanos
12.
J Cell Mol Med ; 28(6): e18129, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38426936

RESUMO

ATP citrate lyase (ACLY), as a key enzyme in lipid metabolism, plays an important role in energy metabolism and lipid biosynthesis of a variety of tumours. Many studies have shown that ACLY is highly expressed in various tumours, and its pharmacological or gene inhibition significantly inhibits tumour growth and progression. However, the roles of ACLY in oesophageal squamous cell carcinoma (ESCC) remain unclear. Here, our data showed that ACLY inhibitor significantly attenuated cell proliferation, migration, invasion and lipid synthesis in different ESCC cell lines, whereas the proliferation, migration, invasion and lipid synthesis of ESCC cells were enhanced after ACLY overexpression. Furthermore, ACLY inhibitor dramatically suppressed tumour growth and lipid metabolism in ESCC cells xenografted tumour model, whereas ACLY overexpression displayed the opposite effect. Mechanistically, ACLY protein harboured acetylated modification and interacted with SIRT2 protein in ESCC cells. The SIRT2 inhibitor AGK2 significantly increased the acetylation level of ACLY protein and inhibited the proliferation and migration of ESCC cells, while overexpression of ACLY partially reversed the inhibitory effect of AGK2 on ESCC cells. Overall, these results suggest that targeting the SIRT2/ACLY signalling axis may be a potential therapeutic strategy for ESCC patients.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , ATP Citrato (pro-S)-Liase , Sirtuína 2/genética , Sirtuína 2/metabolismo , Proliferação de Células , Neoplasias Esofágicas/metabolismo , Lipídeos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica
13.
J Cell Mol Med ; 28(7): e18207, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38506087

RESUMO

Ferroptosis, characterized by iron-dependent lipid reactive oxygen species (ROS) accumulation, plays a pivotal role in cisplatin-induced ototoxicity. Existing research has suggested that in cisplatin-mediated damage to auditory cells and hearing loss, ferroptosis is partially implicated. 4-Octyl itaconate (4-OI), derived from itaconic acid, effectively permeates cell membranes, showcasing potent anti-inflammatory as well as antioxidant effects in several disease models. Our study aimed to investigate the effect of 4-OI on cisplatin-induced ferroptosis and the underlying molecular mechanisms. The survival rates of HEI-OC1 cells and mice cochlea hair cells were measured by CCK8 and immunofluorescence, respectively. The auditory brainstem response (ABR) audiometry was used to detect changes in hearing thresholds in mice before and after treatment. Levels of ROS were evaluated by DCFH-DA. Real-time PCR quantified inflammatory cytokines TNF-α, IL-6 and IL-1ß. Network Pharmacology and RNA sequencing (RNA-seq) analysis of the potential mechanism of 4-OI resistance to cisplatin-induced ferroptosis. The expressions of ferroptosis-related factors (GPX4, SLC7A11 and PTGS2) and important antioxidant factors (NRF2, HO-1, GCLC and NQO1) were tested by real-time PCR, Western blot and immunofluorescence. Results demonstrated cisplatin-induced significant ROS and inflammatory factor release, reduced NRF2 expression, hindered nuclear translocation and activated ferroptosis. Pretreatment with 4-OI exhibited anti-inflammatory and antioxidant effects, along with resistance to ferroptosis, ultimately mitigating cisplatin-induced cell loss. In the present study, we show that 4-OI inhibits cisplatin-induced ferroptosis possibly through activation of the NRF2/HO-1 signalling pathway, thereby exerting a protective effect against cisplatin-induced damage to auditory cells, and providing a new therapeutic strategy for cisplatin-induced hearing loss.


Assuntos
Ferroptose , Perda Auditiva , Succinatos , Animais , Camundongos , Cisplatino/efeitos adversos , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/farmacologia , Apoptose , Anti-Inflamatórios/farmacologia
14.
Am J Transplant ; 24(7): 1132-1145, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38452932

RESUMO

Mycophenolate mofetil (MMF) is one of the most used immunosuppressive drugs in organ transplantation, but frequent gastrointestinal (GI) side effects through unknown mechanisms limit its clinical use. Gut microbiota and its metabolites were recently reported to play a vital role in MMF-induced GI toxicity, but the specific mechanism of how they interact with the human body is still unclear. Here, we found that secondary bile acids (BAs), as bacterial metabolites, were significantly reduced by MMF administration in the gut of mice. Microbiome data and fecal microbiota transfer model supported a microbiota-dependent effect on the reduction of secondary BAs. Supplementation of the secondary BA lithocholic acid alleviated MMF-induced weight loss, colonic inflammation, and oxidative phosphorylation damage. Genetic deletion of the vitamin D3 receptor (VDR), which serves as a primary colonic BA receptor, in colonic epithelial cells (VDRΔIEC) abolished the therapeutic effect of lithocholic acid on MMF-induced GI toxicity. Impressively, we discovered that paricalcitol, a Food and Drug Administration-approved VDR agonist that has been used in clinics for years, could effectively alleviate MMF-induced GI toxicity. Our study reveals a previously unrecognized mechanism of gut microbiota, BAs, and VDR signaling in MMF-induced GI side effects, offering potential therapeutic strategies for clinics.


Assuntos
Ácidos e Sais Biliares , Microbioma Gastrointestinal , Ácido Micofenólico , Receptores de Calcitriol , Animais , Ácido Micofenólico/farmacologia , Camundongos , Microbioma Gastrointestinal/efeitos dos fármacos , Receptores de Calcitriol/metabolismo , Ácidos e Sais Biliares/metabolismo , Imunossupressores , Camundongos Endogâmicos C57BL , Masculino , Gastroenteropatias/induzido quimicamente , Ácido Litocólico , Humanos
15.
Development ; 148(17)2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34373913

RESUMO

Neutrophils are the most abundant vertebrate leukocytes and they are essential to host defense. Despite extensive investigation, the molecular network controlling neutrophil differentiation remains incompletely understood. GFI1 is associated with several myeloid disorders, but its role and the role of its co-regulators in granulopoiesis and pathogenesis are far from clear. Here, we demonstrate that zebrafish gfi1aa deficiency induces excessive neutrophil progenitor proliferation, accumulation of immature neutrophils from the embryonic stage, and some phenotypes similar to myelodysplasia syndrome in adulthood. Both genetic and epigenetic analyses demonstrate that immature neutrophil accumulation in gfi1aa-deficient mutants is due to upregulation of cebpa transcription. Increased transcription was associated with Lsd1-altered H3K4 methylation of the cebpa regulatory region. Taken together, our results demonstrate that Gfi1aa, Lsd1 and cebpa form a regulatory network that controls neutrophil development, providing a disease progression-traceable model for myelodysplasia syndrome. Use of this model could provide new insights into the molecular mechanisms underlying GFI1-related myeloid disorders as well as a means by which to develop targeted therapeutic approaches for treatment.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/metabolismo , Proteínas de Ligação a DNA/metabolismo , Hematopoese/genética , Histona Desmetilases/metabolismo , Neutrófilos/citologia , Proteínas de Peixe-Zebra/metabolismo , Animais , Proteínas Estimuladoras de Ligação a CCAAT/genética , Diferenciação Celular , Proliferação de Células , Proteínas de Ligação a DNA/deficiência , Embrião não Mamífero , Epigênese Genética , Células Precursoras de Granulócitos/citologia , Células Precursoras de Granulócitos/metabolismo , Histona Desmetilases/genética , Neutrófilos/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/deficiência , Proteínas de Peixe-Zebra/genética
16.
Breast Cancer Res Treat ; 204(3): 465-474, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38183514

RESUMO

PURPOSE: The potential of targeting forkhead box C1 (FOXC1) as a therapeutic approach for triple-negative breast cancer (TNBC) is promising. However, a comprehensive understanding of FOXC1 regulation, particularly upstream factors, remains elusive. Expression of the L1 cell adhesion molecule (L1CAM), a transmembrane glycoprotein associated with brain metastasis, was observed to be positively associated with FOXC1 transcripts. Thus, this study aims to investigate their relationship in TNBC progression. METHODS: Publicly available FOXC1 and L1CAM transcriptomic data were obtained, and their corresponding proteins were analyzed in four TNBC cell lines. In BT549 cells, FOXC1 and L1CAM were individually silenced, while L1CAM was overexpressed in BT549-shFOXC1, MDA-MB-231, and HCC1937 cells. CCK-8, transwell, and wound healing assays were performed in these cell lines, and immunohistochemical staining was conducted in tumor samples. RESULTS: A positive correlation between L1CAM and FOXC1 transcripts was observed in publicly available datasets. In BT549 cells, knockdown of FOXC1 led to reduced L1CAM expression at both the transcriptional and protein levels, and conversely, silencing of L1CAM decreased FOXC1 protein levels, but interestingly, FOXC1 transcripts remained largely unaffected. Overexpressing L1CAM resulted in increased FOXC1 protein expression without significant changes in FOXC1 mRNA levels. This trend was also observed in BT549-shFOXC1, MDA-MB-231-L1CAM, and HCC1937-L1CAM cells. Notably, alterations in FOXC1 or L1CAM levels corresponded to changes in cell proliferation, migration, and invasion capacities. Furthermore, a positive correlation between L1CAM and FOXC1 protein expression was detected in human TNBC tumors. CONCLUSION: FOXC1 and L1CAM exhibit co-regulation at the protein level, with FOXC1 regulating at the transcriptional level and L1CAM regulating at the post-transcriptional level, and together they positively influence cell proliferation, migration, and invasion in TNBC.


Assuntos
Fatores de Transcrição Forkhead , Molécula L1 de Adesão de Célula Nervosa , Neoplasias de Mama Triplo Negativas , Humanos , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , Molécula L1 de Adesão de Célula Nervosa/genética , Molécula L1 de Adesão de Célula Nervosa/metabolismo , Molécula L1 de Adesão de Célula Nervosa/uso terapêutico , Neoplasias de Mama Triplo Negativas/patologia
17.
Small ; 20(1): e2303832, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37670542

RESUMO

Protonation has been considered essential for the pseudocapacitive energy storage of polyaniline (PANI) for years, as proton doping in PANI chains not only activates electron transport pathways, but also promotes the proceeding of redox reactions. Rarely has the ability for PANI of storing energy without protonation been investigated, and it remains uncertain whether PANI has pseudocapacitive charge storage properties in an alkaline electrolyte. Here, this work first demonstrates the pseudocapacitive energy storage for PANI without protonation using a PANI/graphene composite as a model material in an alkaline electrolyte. Using in situ Raman spectroscopy coupled with electrochemical quartz crystal microbalance (EQCM) measurements, this work determines the formation of -N= group over potential on a PANI chain and demonstrates the direct contribution of OH- in the nonprotonation type of oxidation reactions. This work finds that the PANI/graphene composite in an alkaline electrolyte has excellent cycling stability with a wider operation voltage of 1 V as well as a slightly higher specific capacitance than that in an acidic electrolyte. The findings provide a new perspective on pseudocapacitive energy storage of PANI-based composites, which will influence the selection of electrolytes for PANI materials and expand their application in energy storage fields.

18.
Small ; : e2403345, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39118557

RESUMO

Although brightness and efficiency have been continually improved, the inability to achieve superior efficiency, color stability, and low-efficiency roll-off simultaneously in white organic light-emitting diodes (OLEDs) remains a knotty problem restricting the commercial application. In this paper, emission balance for two different horizontal orientation emitting molecules is maintained by using hole transport materials and bipolar host materials to control carriers' recombination and exciton diffusion. Impressively, the obtained devices exhibit extremely stable white emission with small chromaticity coordinates variation of (0.0023, 0.0078) over a wide brightness range from 1000 to 50000 cd m-2. Meanwhile, the optimal white OLED realizes the power efficiency, current efficiency, and external quantum efficiency up to 70.68 lm W-1, 85.53 cd A-1, and 24.33%, respectively at the practical brightness of 1000 cd m-2. Owing to reduced heterogeneous interfaces and broadening recombination region, this device exhibits a high EQE over 20% under high luminance of 10000 cd m-2, demonstrating slight efficiency roll-off. The operating mechanism of the device is analyzed by versatile experimental and theoretical evidences, which concludes precise manipulation of charges and excitons is the key points to achieve these excellent performances. This work provides an effective strategy for the design of high-performance white OLEDs.

19.
J Transl Med ; 22(1): 816, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223664

RESUMO

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative condition characterized by the loss of dopaminergic neurons and the accumulation of Lewy-body protein aggregates containing misfolded α-synuclein (α-syn) in a phosphorylated form. The lack of effective models for drug screens has hindered drug development studies for PD. However, the recent development of in vitro brain-like organoids provides a new opportunity for evaluating therapeutic agents to slow the progression of this chronic disease. METHODS: In this study, we used a 3D brain-like organoid model to investigate the potential of repurposing Tilorone, an anti-viral drug, for impeding the propagation of α-synucleinopathy. We assessed the effect of Tilorone on the uptake of fluorescently labeled α-syn preformed fibrils (sPFF) and sPFF-induced apoptosis using confocal microscopy. We also examined Tilorone's impact on the phosphorylation of endogenous α-syn induced by pathogenic sPFF by immunoblotting midbrain-like organoid extracts. Additionally, quantitative RT-PCR and proteomic profiling of sPFF-treated organoids were conducted to evaluate the global impact of Tilorone treatment on tissue homeostasis in the 3D organoid model. RESULTS: Tilorone inhibits the uptake of sPFF in both mouse primary neurons and human midbrain-like organoids. Tilorone also reduces the phosphorylation of endogenous α-syn induced by pathogenic α-syn fibrils and mitigates α-syn fibril-induced apoptosis in midbrain-like organoids. Proteomic profiling of fibril-treated organoids reveals substantial alterations in lipid homeostasis by α-syn fibrils, which are reversed by Tilorone treatment. Given its safety profile in clinics, Tilorone may be further developed as a therapeutic intervention to alleviate the propagation of synucleinopathy in PD patients.


Assuntos
Mesencéfalo , Organoides , Sinucleinopatias , alfa-Sinucleína , Mesencéfalo/patologia , Mesencéfalo/efeitos dos fármacos , Mesencéfalo/metabolismo , Organoides/efeitos dos fármacos , Organoides/metabolismo , Organoides/patologia , Humanos , alfa-Sinucleína/metabolismo , Sinucleinopatias/patologia , Sinucleinopatias/metabolismo , Sinucleinopatias/tratamento farmacológico , Fosforilação/efeitos dos fármacos , Modelos Biológicos , Apoptose/efeitos dos fármacos , Animais , Doença de Parkinson/patologia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Camundongos , Proteômica
20.
BMC Microbiol ; 24(1): 160, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38724904

RESUMO

BACKGROUND: Antibiotic-associated diarrhea (AAD) refers to symptoms of diarrhea that cannot be explained by other causes after the use of antibiotics. AAD is thought to be caused by a disruption of intestinal ecology due to antibiotics. Fecal Microbiota Transplantation (FMT) is a treatment method that involves transferring microbial communities from the feces of healthy individuals into the patient's gut. METHOD: We selected 23 AAD patients who received FMT treatment in our department. Before FMT, we documented patients' bowel movement frequency, abdominal symptoms, routine blood tests, and inflammatory markers, and collected fecal samples for 16S rRNA sequencing to observe changes in the intestinal microbiota. Patients' treatment outcomes were followed up 1 month and 3 months after FMT. RESULTS: Out of the 23 AAD patients, 19 showed a clinical response to FMT with alleviation of abdominal symptoms. Among them, 82.61% (19/23) experienced relief from diarrhea, 65% (13/20) from abdominal pain, 77.78% (14/18) from abdominal distension, and 57.14% (4/7) from bloody stools within 1 month after FMT. Inflammatory markers IL-8 and CRP significantly decreased after FMT, but there were no noticeable changes in WBC, IL-6, and TNF-α before and after transplantation. After FMT, the abundance of Bacteroides and Faecalibacterium increased in patients' fecal samples, while the abundance of Escherichia-Shigella and Veillonella decreased. CONCLUSION: FMT has a certain therapeutic effect on AAD, and can alleviate abdominal symptoms and change the intestinal microbiota of patients.


Assuntos
Antibacterianos , Diarreia , Transplante de Microbiota Fecal , Fezes , Microbioma Gastrointestinal , RNA Ribossômico 16S , Humanos , Diarreia/microbiologia , Diarreia/terapia , Transplante de Microbiota Fecal/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Antibacterianos/efeitos adversos , Fezes/microbiologia , Adulto , RNA Ribossômico 16S/genética , Idoso , Resultado do Tratamento , Bactérias/classificação , Bactérias/isolamento & purificação , Bactérias/genética
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