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1.
Cell ; 169(2): 286-300.e16, 2017 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-28388412

RESUMO

The activation of mixed lineage kinase-like (MLKL) by receptor-interacting protein kinase-3 (RIPK3) results in plasma membrane (PM) disruption and a form of regulated necrosis, called necroptosis. Here, we show that, during necroptosis, MLKL-dependent calcium (Ca2+) influx and phosphatidylserine (PS) exposure on the outer leaflet of the plasma membrane preceded loss of PM integrity. Activation of MLKL results in the generation of broken, PM "bubbles" with exposed PS that are released from the surface of the otherwise intact cell. The ESCRT-III machinery is required for formation of these bubbles and acts to sustain survival of the cell when MLKL activation is limited or reversed. Under conditions of necroptotic cell death, ESCRT-III controls the duration of plasma membrane integrity. As a consequence of the action of ESCRT-III, cells undergoing necroptosis can express chemokines and other regulatory molecules and promote antigenic cross-priming of CD8+ T cells.


Assuntos
Membrana Celular/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Necrose/metabolismo , Animais , Cálcio/metabolismo , Sobrevivência Celular , Células HT29 , Humanos , Células Jurkat , Camundongos , Células NIH 3T3 , Fosfatidilserinas , Proteínas Quinases/metabolismo , Transdução de Sinais
2.
Cell ; 157(5): 1189-202, 2014 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-24813850

RESUMO

Receptor-interacting protein kinase (RIPK)-1 is involved in RIPK3-dependent and -independent signaling pathways leading to cell death and/or inflammation. Genetic ablation of ripk1 causes postnatal lethality, which was not prevented by deletion of ripk3, caspase-8, or fadd. However, animals that lack RIPK1, RIPK3, and either caspase-8 or FADD survived weaning and matured normally. RIPK1 functions in vitro to limit caspase-8-dependent, TNFR-induced apoptosis, and animals lacking RIPK1, RIPK3, and TNFR1 survive to adulthood. The role of RIPK3 in promoting lethality in ripk1(-/-) mice suggests that RIPK3 activation is inhibited by RIPK1 postbirth. Whereas TNFR-induced RIPK3-dependent necroptosis requires RIPK1, cells lacking RIPK1 were sensitized to necroptosis triggered by poly I:C or interferons. Disruption of TLR (TRIF) or type I interferon (IFNAR) signaling delayed lethality in ripk1(-/-)tnfr1(-/-) mice. These results clarify the complex roles for RIPK1 in postnatal life and provide insights into the regulation of FADD-caspase-8 and RIPK3-MLKL signaling by RIPK1.


Assuntos
Caspase 8/metabolismo , Genes Letais , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Animais Recém-Nascidos , Apoptose , Caspase 8/genética , Morte Celular , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Proteína de Domínio de Morte Associada a Fas/metabolismo , Fibroblastos/metabolismo , Inflamação/metabolismo , Interferons/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Fatores de Necrose Tumoral/metabolismo
3.
Semin Cell Dev Biol ; 156: 93-106, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-37648621

RESUMO

The plasma membrane is crucial to the survival of animal cells, and damage to it can be lethal, often resulting in necrosis. However, cells possess multiple mechanisms for repairing the membrane, which allows them to maintain their integrity to some extent, and sometimes even survive. Interestingly, cells that survive a near-necrosis experience can recognize sub-lethal membrane damage and use it as a signal to secrete chemokines and cytokines, which activate the immune response. This review will present evidence of necrotic cell survival in both in vitro and in vivo systems, including in C. elegans, mouse models, and humans. We will also summarize the various membrane repair mechanisms cells use to maintain membrane integrity. Finally, we will propose a mathematical model to illustrate how near-death experiences can transform dying cells into innate immune modulators for their microenvironment. By utilizing their membrane repair activity, the biological effects of cell death can extend beyond the mere elimination of the cells.


Assuntos
Caenorhabditis elegans , Imunidade Inata , Humanos , Animais , Camundongos , Necrose/metabolismo , Morte Celular , Membrana Celular/metabolismo
4.
Blood ; 143(1): 32-41, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-37824804

RESUMO

ABSTRACT: Chronic active Epstein-Barr virus (EBV) disease (CAEBV) is a lethal syndrome because of persistent EBV infection. When diagnosed as CAEBV, EBV infection was observed in multiple hematopoietic lineages, but the etiology of CAEBV is still elusive. Bone marrow and peripheral cells derived from 5 patients with CAEBV, 1 patient with EBV-associated hemophagocytic lymphohistiocytosis, and 2 healthy controls were analyzed. Multiple assays were applied to identify and characterize EBV-infected cells, including quantitative polymerase chain reaction, PrimeFlow, and single-cell RNA-sequencing (scRNA-seq). Based on scRNA-seq data, alterations in gene expression of particular cell types were analyzed between patients with CAEBV and controls, and between infected and uninfected cells. One patient with CAEBV was treated with allogeneic hematopoietic stem cell transplantation (HSCT), and the samples derived from this patient were analyzed again 6 months after HSCT. EBV infected the full spectrum of the hematopoietic system including both lymphoid and myeloid lineages, as well as the hematopoietic stem cells (HSCs) of the patients with CAEBV. EBV-infected HSCs exhibited a higher differentiation rate toward downstream lineages, and the EBV infection had an impact on both the innate and adaptive immunity, resulting in inflammatory symptoms. EBV-infected cells were thoroughly removed from the hematopoietic system after HSCT. Taken together, multiple lines of evidence presented in this study suggest that CAEBV disease originates from the infected HSCs, which might potentially lead to innovative therapy strategies for CAEBV.


Assuntos
Infecções por Vírus Epstein-Barr , Linfo-Histiocitose Hemofagocítica , Humanos , Herpesvirus Humano 4/genética , Doença Crônica , Linfo-Histiocitose Hemofagocítica/complicações , Células-Tronco Hematopoéticas
5.
Hepatology ; 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39348425

RESUMO

BACKGROUND AND AIMS: Patients with aggressive HCC have limited therapeutic options. Therefore, a better understanding of HCC pathogenesis is needed to improve treatment. Genomic studies of HCC have improved our understanding of cancer biology. However, the ubiquitomic characteristics of HCC remain poorly understood. We aimed to reveal the ubiquitomic characteristics of HCC and provide clinical feature biomarkers of the aggressive HCC that may be used for diagnosis or therapy in the clinic. APPROACH AND RESULTS: The comprehensive proteomic, phosphoproteomic, and ubiquitomic analyses were performed on tumors and adjacent normal liver tissues from 85 patients with HCC. HCCs displayed overexpression of drugable targets CBR1-S151 and CPNE1-S55. COL4A1, LAMC1, and LAMA4 were highly expressed in the disease free survival-poor patients. Phosphoproteomic and ubiquitomic features of HCC revealed cross talk in metabolism and metastasis. Ubiquitomics predicted diverse prognosis and clarified HCC subtype-specific proteomic signatures. Expression of biomarkers TUBA1A, BHMT2, BHMT, and ACY1 exhibited differential ubiquitination levels and displayed high prognostic risk scores, suggesting that targeting these proteins or their modified forms may be beneficial for future clinical treatment. We validated that TUBA1A K370 deubiquitination drove severe HCC and labeled an aggressive subtype of HCCs. TUBA1A K370 deubiquitination was at least partly attributed to protein kinase B-mediated USP14 activation in HCC. Notably, targeting AKT-USP14-TUBA1A complex promoted TUBA1A degradation and blocked liver tumorigenesis in vivo. CONCLUSIONS: This study expands our knowledge of ubiquitomic signatures, biomarkers, and potential therapeutic targets in HCC.

6.
Ann Neurol ; 95(3): 442-458, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38062617

RESUMO

OBJECTIVE: X-linked adrenoleukodystrophy is caused by mutations in the peroxisomal half-transporter ABCD1. The most common manifestation is adrenomyeloneuropathy, a hereditary spastic paraplegia of adulthood. The present study set out to understand the role of neuronal ABCD1 in mice and humans with adrenomyeloneuropathy. METHODS: Neuronal expression of ABCD1 during development was assessed in mice and humans. ABCD1-deficient mice and human brain tissues were examined for corresponding pathology. Next, we silenced ABCD1 in cholinergic Sh-sy5y neurons to investigate its impact on neuronal function. Finally, we tested adeno-associated virus vector-mediated ABCD1 delivery to the brain in mice with adrenomyeloneuropathy. RESULTS: ABCD1 is highly expressed in neurons located in the periaqueductal gray matter, basal forebrain and hypothalamus. In ABCD1-deficient mice (Abcd1-/y), these structures showed mild accumulations of α-synuclein. Similarly, healthy human controls had high expression of ABCD1 in deep gray nuclei, whereas X-ALD patients showed increased levels of phosphorylated tau, gliosis, and complement activation in those same regions, albeit not to the degree seen in neurodegenerative tauopathies. Silencing ABCD1 in Sh-sy5y neurons impaired expression of functional proteins and decreased acetylcholine levels, similar to observations in plasma of Abcd1-/y mice. Notably, hind limb clasping in Abcd1-/y mice was corrected through transduction of ABCD1 in basal forebrain neurons following intracerebroventricular gene delivery. INTERPRETATION: Our study suggests that the basal forebrain-cortical cholinergic pathway may contribute to dysfunction in adrenomyeloneuropathy. Rescuing peroxisomal transport activity in basal forebrain neurons and supporting glial cells might represent a viable therapeutic strategy. ANN NEUROL 2024;95:442-458.


Assuntos
Adrenoleucodistrofia , Prosencéfalo Basal , Neuroblastoma , Humanos , Animais , Camundongos , Adulto , Adrenoleucodistrofia/genética , Adrenoleucodistrofia/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Prosencéfalo Basal/metabolismo , Neurônios/metabolismo , Colinérgicos , Membro 1 da Subfamília D de Transportadores de Cassetes de Ligação de ATP/genética
7.
Mol Ther ; 32(8): 2584-2603, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38845196

RESUMO

Systemic administration of adeno-associated virus (AAV) vectors for spinal cord gene therapy has challenges including toxicity at high doses and pre-existing immunity that reduces efficacy. Intrathecal (IT) delivery of AAV vectors into cerebral spinal fluid can avoid many issues, although distribution of the vector throughout the spinal cord is limited, and vector entry to the periphery sometimes initiates hepatotoxicity. Here we performed biopanning in non-human primates (NHPs) with an IT injected AAV9 peptide display library. We identified top candidates by sequencing inserts of AAV DNA isolated from whole tissue, nuclei, or nuclei from transgene-expressing cells. These barcoded candidates were pooled with AAV9 and compared for biodistribution and transgene expression in spinal cord and liver of IT injected NHPs. Most candidates displayed increased retention in spinal cord compared with AAV9. Greater spread from the lumbar to the thoracic and cervical regions was observed for several capsids. Furthermore, several capsids displayed decreased biodistribution to the liver compared with AAV9, providing a high on-target/low off-target biodistribution. Finally, we tested top candidates in human spinal cord organoids and found them to outperform AAV9 in efficiency of transgene expression in neurons and astrocytes. These capsids have potential to serve as leading-edge delivery vehicles for spinal cord-directed gene therapies.


Assuntos
Dependovirus , Terapia Genética , Vetores Genéticos , Medula Espinal , Dependovirus/genética , Animais , Medula Espinal/metabolismo , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Humanos , Terapia Genética/métodos , Transgenes , Técnicas de Transferência de Genes , Capsídeo/metabolismo , Distribuição Tecidual , Injeções Espinhais , Transdução Genética , Macaca mulatta , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo
8.
PLoS Genet ; 18(11): e1010506, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36441670

RESUMO

Short telomeres induce a DNA damage response (DDR) that evokes apoptosis and senescence in human cells. An extant question is the contribution of telomere dysfunction-induced DDR to the phenotypes observed in aging and telomere biology disorders. One candidate is RAP1, a telomere-associated protein that also controls transcription at extratelomeric regions. To distinguish these roles, we generated a knockin mouse carrying a mutated Rap1, which was incapable of binding telomeres and did not result in eroded telomeres or a DDR. Primary Rap1 knockin embryonic fibroblasts showed decreased RAP1 expression and re-localization away from telomeres, with an increased cytosolic distribution akin to that observed in human fibroblasts undergoing telomere erosion. Rap1 knockin mice were viable, but exhibited transcriptomic alterations, proinflammatory cytokine/chemokine signaling, reduced lifespan, and decreased healthspan with increased body weight/fasting blood glucose levels, spontaneous tumor incidence, and behavioral deficits. Taken together, our data present mechanisms distinct from telomere-induced DDR that underlie age-related phenotypes.


Assuntos
Complexo Shelterina , Telômero , Animais , Humanos , Camundongos , Longevidade , Fenótipo , Telômero/genética , Encurtamento do Telômero
9.
Genes Dev ; 31(1): 46-58, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28115467

RESUMO

Resection of double-strand breaks (DSBs) plays a critical role in their detection and appropriate repair. The 3' ssDNA protrusion formed through resection activates the ATR-dependent DNA damage response (DDR) and is required for DSB repair by homologous recombination (HR). Here we report that PHF11 (plant homeodomain finger 11) encodes a previously unknown DDR factor involved in 5' end resection, ATR signaling, and HR. PHF11 was identified based on its association with deprotected telomeres and localized to sites of DNA damage in S phase. Depletion of PHF11 diminished the ATR signaling response to telomere dysfunction and genome-wide DNA damage, reduced end resection at sites of DNA damage, resulted in compromised HR and misrejoining of S-phase DSBs, and increased the sensitivity to DNA-damaging agents. PHF11 interacted with the ssDNA-binding protein RPA and was found in a complex with several nucleases, including the 5' dsDNA exonuclease EXO1. Biochemical experiments demonstrated that PHF11 stimulates EXO1 by overcoming its inhibition by RPA, suggesting that PHF11 acts (in part) by promoting 5' end resection at RPA-bound sites of DNA damage. These findings reveal a role for PHF11 in DSB resection, DNA damage signaling, and DSB repair.


Assuntos
Quebras de DNA de Cadeia Dupla , Reparo do DNA/genética , Proteínas de Ligação a DNA/metabolismo , Recombinação Homóloga/genética , Transdução de Sinais/genética , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular , Proteínas de Ligação a DNA/genética , Exodesoxirribonucleases/metabolismo , Células HEK293 , Humanos , Camundongos , Transporte Proteico , Fatores de Transcrição/genética
10.
EMBO J ; 39(21): e103420, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-32935380

RESUMO

Short telomeres are a principal defining feature of telomere biology disorders, such as dyskeratosis congenita (DC), for which there are no effective treatments. Here, we report that primary fibroblasts from DC patients and late generation telomerase knockout mice display lower nicotinamide adenine dinucleotide (NAD) levels, and an imbalance in the NAD metabolome that includes elevated CD38 NADase and reduced poly(ADP-ribose) polymerase and SIRT1 activities, respectively, affecting many associated biological pathways. Supplementation with the NAD precursor, nicotinamide riboside, and CD38 inhibition improved NAD homeostasis, thereby alleviating telomere damage, defective mitochondrial biosynthesis and clearance, cell growth retardation, and cellular senescence of DC fibroblasts. These findings reveal a direct, underlying role of NAD dysregulation when telomeres are short and underscore its relevance to the pathophysiology and interventions of human telomere-driven diseases.


Assuntos
Disceratose Congênita/genética , Disceratose Congênita/metabolismo , Fibroblastos/metabolismo , NAD/metabolismo , Telomerase/genética , Telômero/metabolismo , ADP-Ribosil Ciclase 1/genética , Animais , Encéfalo/patologia , Linhagem Celular , Senescência Celular , Disceratose Congênita/patologia , Feminino , Homeostase , Humanos , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Knockout , Mitocôndrias/metabolismo , Niacinamida/análogos & derivados , Niacinamida/metabolismo , Fenótipo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Compostos de Piridínio/metabolismo , Telomerase/metabolismo
11.
J Transl Med ; 22(1): 561, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867256

RESUMO

BACKGROUND: Fibrogenesis within ovarian endometrioma (endometrioma), mainly induced by transforming growth factor-ß (TGF-ß), is characterized by myofibroblast over-activation and excessive extracellular matrix (ECM) deposition, contributing to endometrioma-associated symptoms such as infertility by impairing ovarian reserve and oocyte quality. However, the precise molecular mechanisms that underpin the endometrioma- associated fibrosis progression induced by TGF-ß remain poorly understood. METHODS: The expression level of lysine acetyltransferase 14 (KAT14) was validated in endometrium biopsies from patients with endometrioma and healthy controls, and the transcription level of KAT14 was further confirmed by analyzing a published single-cell transcriptome (scRNA-seq) dataset of endometriosis. We used overexpression, knockout, and knockdown approaches in immortalized human endometrial stromal cells (HESCs) or human primary ectopic endometrial stromal cells (EcESCs) to determine the role of KAT14 in TGF-ß-induced fibrosis. Furthermore, an adeno-associated virus (AAV) carrying KAT14-shRNA was used in an endometriosis mice model to assess the role of KAT14 in vivo. RESULTS: KAT14 was upregulated in ectopic lesions from endometrioma patients and predominantly expressed in activated fibroblasts. In vitro studies showed that KAT14 overexpression significantly promoted a TGF-ß-induced profibrotic response in endometrial stromal cells, while KAT14 silencing showed adverse effects that could be rescued by KAT14 re-enhancement. In vivo, Kat14 knockdown ameliorated fibrosis in the ectopic lesions of the endometriosis mouse model. Mechanistically, we showed that KAT14 directly interacted with serum response factor (SRF) to promote the expression of α-smooth muscle actin (α-SMA) by increasing histone H4 acetylation at promoter regions; this is necessary for TGF-ß-induced ECM production and myofibroblast differentiation. In addition, the knockdown or pharmacological inhibition of SRF significantly attenuated KAT14-mediating profibrotic effects under TGF-ß treatment. Notably, the KAT14/SRF complex was abundant in endometrioma samples and positively correlated with α-SMA expression, further supporting the key role of KAT14/SRF complex in the progression of endometrioma-associated fibrogenesis. CONCLUSION: Our results shed light on KAT14 as a key effector of TGF-ß-induced ECM production and myofibroblast differentiation in EcESCs by promoting histone H4 acetylation via co-operating with SRF, representing a potential therapeutic target for endometrioma-associated fibrosis.


Assuntos
Endometriose , Fibrose , Fator de Resposta Sérica , Fator de Crescimento Transformador beta , Adulto , Animais , Feminino , Humanos , Camundongos , Endometriose/patologia , Endometriose/metabolismo , Endométrio/metabolismo , Endométrio/patologia , Histona Acetiltransferases/metabolismo , Miofibroblastos/metabolismo , Miofibroblastos/patologia , Fator de Resposta Sérica/metabolismo , Células Estromais/metabolismo , Células Estromais/patologia , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
12.
Appl Environ Microbiol ; 90(7): e0071424, 2024 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-38940583

RESUMO

Oligotrophic deep-water lakes are unique and sensitive ecosystems with limited nutrient availability. Understanding bacterial communities within these lakes is crucial for assessing ecosystem health, biogeochemical cycling, and responses to environmental changes. In this study, we investigated the seasonal and vertical dynamics of both free-living (FL) and particle-attached (PA) bacteria in Lake Fuxian, a typical oligotrophic deep freshwater lake in southeast China. Our findings revealed distinct seasonal and vertical dynamics of FL and PA bacterial communities, driven by similar physiochemical environmental factors. PA bacteria exhibited higher α- and ß-diversity and were enriched with Proteobacteria, Cyanobacteria, Firmicutes, Patescibacteria, Planctomycetota, and Verrucomicrobiota, while FL bacteria were enriched with Actinobacteria and Bacteroidota. FL bacteria showed enrichment in putative functions related to chemoheterotrophy and aerobic anoxygenic photosynthesis, whereas the PA fraction was enriched with intracellular parasites (mainly contributed by Rickettsiales, Chlamydiales, and Legionellales) and nitrogen metabolism functions. Deterministic processes predominantly shaped the assembly of both FL and PA bacterial communities, with stochastic processes playing a greater role in the FL fraction. Network analysis revealed extensive species interactions, with a higher proportion of positively correlated edges in the PA network, indicating mutualistic or cooperative interactions. Cyanobium, Comamonadaceae, and Roseomonas were identified as keystone taxa in the PA network, underscoring potential cooperation between autotrophic and heterotrophic bacteria in organic particle microhabitats. Overall, the disparities in bacterial diversity, community composition, putative function, and network characteristics between FL and PA fractions highlight their adaptation to distinct ecological niches within these unique lake ecosystems.IMPORTANCEUnderstanding the diversity of microbial communities, their assembly mechanisms, and their responses to environmental changes is fundamental to the study of aquatic microbial ecology. Oligotrophic deep-water lakes are fragile ecosystems with limited nutrient resources, rendering them highly susceptible to environmental fluctuations. Examining different bacterial types within these lakes offers valuable insights into the intricate mechanisms governing community dynamics and adaptation strategies across various scales. In our investigation of oligotrophic deep freshwater Lake Fuxian in China, we explored the seasonal and vertical dynamics of two bacterial types: free-living (FL) and particle-attached (PA). Our findings unveiled distinct patterns in the diversity, composition, and putative functions of these bacteria, all shaped by environmental factors. Understanding these subtleties provides insight into bacterial interactions, thereby influencing the overall ecosystem functioning. Ultimately, our research illuminates the adaptation and roles of FL and PA bacteria within these unique lake environments, contributing significantly to our broader comprehension of ecosystem stability and health.


Assuntos
Bactérias , Lagos , Microbiota , Lagos/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , China , Ecossistema , Estações do Ano
13.
BMC Microbiol ; 24(1): 348, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39277721

RESUMO

BACKGROUND: Oligotrophy and hypereutrophy represent the two extremes of lake trophic states, and understanding the distribution of bacterial communities across these contrasting conditions is crucial for advancing aquatic microbial research. Despite the significance of these extreme trophic states, bacterial community characteristics and co-occurrence patterns in such environments have been scarcely interpreted. To bridge this knowledge gap, we collected 60 water samples from Lake Fuxian (oligotrophic) and Lake Xingyun (hypereutrophic) during different hydrological periods. RESULTS: Employing 16S rRNA gene sequencing, our findings revealed distinct community structures and metabolic potentials in bacterial communities of hypereutrophic and oligotrophic lake ecosystems. The hypereutrophic ecosystem exhibited higher bacterial α- and ß-diversity compared to the oligotrophic ecosystem. Actinobacteria dominated the oligotrophic Lake Fuxian, while Cyanobacteria, Proteobacteria, and Bacteroidetes were more prevalent in the hypereutrophic Lake Xingyun. Functions associated with methanol oxidation, methylotrophy, fermentation, aromatic compound degradation, nitrogen/nitrate respiration, and nitrogen/nitrate denitrification were enriched in the oligotrophic lake, underscoring the vital role of bacteria in carbon and nitrogen cycling. In contrast, functions related to ureolysis, human pathogens, animal parasites or symbionts, and phototrophy were enriched in the hypereutrophic lake, highlighting human activity-related disturbances and potential pathogenic risks. Co-occurrence network analysis unveiled a more complex and stable bacterial network in the hypereutrophic lake compared to the oligotrophic lake. CONCLUSION: Our study provides insights into the intricate relationships between trophic states and bacterial community structure, emphasizing significant differences in diversity, community composition, and network characteristics between extreme states of oligotrophy and hypereutrophy. Additionally, it explores the nuanced responses of bacterial communities to environmental conditions in these two contrasting trophic states.


Assuntos
Bactérias , Biodiversidade , Lagos , Filogenia , RNA Ribossômico 16S , Lagos/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Microbiota/genética , Ecossistema , Microbiologia da Água , China , Nitrogênio/metabolismo , Análise de Sequência de DNA
14.
Opt Lett ; 49(17): 4954-4957, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39208004

RESUMO

In recent years, III-Nitride-based micro light-emitting diodes (micro-LEDs) have emerged in many fields and gained more attention. However, fabricating high-efficiency micro-LEDs still remains a challenge due to the presence of sidewall damage. In this study, a GaN-based single blue micro-LED with a full-M-sided hexagonal mesa was prepared. The mesa has a circumradius of 10 µm and was treated with a tetramethylammonium hydroxide (TMAH) solution. Experimental results show that the sidewall defects introduced by dry etching damage act as non-radiative recombination centers and greatly impair the performance of the device. By constructing a full-M-sided hexagonal structure and soaking in a TMAH solution, the etching damage on the sidewall can be eliminated to the greatest extent, thereby reducing sidewall defects. In consequence, the peak EQE of the devices treated with the TMAH solution exceeded 10% at low current density, an increase of 9% compared with the untreated samples. This work provides, to our knowledge, a new approach to improving the efficiency of GaN-based micro-LEDs.

15.
Anal Biochem ; 695: 115635, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39098372

RESUMO

In this paper, we introduced a novel phase-transfer strategy tailored for the efficient batch detection of ascorbic acid in vitamin C tablets. This method entailed the reaction between ascorbic acid and an excess of potassium permanganate. Subsequent reaction of the residual potassium permanganate with sodium oxalate in an acidic medium led to the generation of carbon dioxide. The quantification of the produced carbon dioxide was achieved using headspace GC, enabling the indirect measurement of ascorbic acid. The obtained findings revealed that the headspace method exhibited satisfied precision with a relative standard deviation of less than 2.11 % and high sensitivity with a limit of quantitation of 0.27 µmol. These results firmly establish the reliability of this innovative approach for determining ascorbic acid. In addition, the highly automated feature of headspace method significantly enhances the efficiency of batch sample detection and reduces the errors caused by human operation. Thus, the adoption of the transformed phase strategy has demonstrated its effectiveness in assessing ascorbic acid, especially for large-scale sample analysis in industrial applications, owing to its efficiency, precision, and sensitivity.


Assuntos
Ácido Ascórbico , Permanganato de Potássio , Comprimidos , Ácido Ascórbico/análise , Ácido Ascórbico/química , Permanganato de Potássio/química , Cromatografia Gasosa/métodos , Dióxido de Carbono/análise , Dióxido de Carbono/química
16.
FASEB J ; 37(12): e23286, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37950623

RESUMO

Drug-induced liver injury (DILI) is frequently induced by high dose of acetaminophen (APAP) and is concomitant with disturbances of gut flora. Akkermansia muciniphila is beneficial for the repair of liver injury. Lycium barbarum polysaccharide, yam polysaccharide, and chrysanthemum polysaccharide all have anti-inflammatory and antioxidation effects. The objective of this study is to investigate the potential of lycium barbarum polysaccharide, yam polysaccharide, and chrysanthemum polysaccharide (LYC) in improving DILI by increasing the abundance of A. muciniphila. Initially, screening for the optimal concentrations of wolfberry, yam, and chrysanthemum (WYC) or LYC to promote A. muciniphila proliferation in vitro and validated in antibiotic (ATB)-treated KM mice. Subsequently, APAP-induced DILI model in BALB/c mice were constructed to examine the treatment effects of LYC. Our findings indicate that the optimal concentration ratio of WYC was 2:3:2, and LYC was 1:1:1. WYC increased A. muciniphila proliferation in vitro and in ATB-treated mice under this ratio. Meanwhile, LYC increased A. muciniphila abundance in vitro and the combination LYC with A. muciniphila promoted the proliferation of A. muciniphila in ATB-treated mice. The overdose of APAP resulted in the impairment of the intestinal barrier function and subsequent leakage of lipopolysaccharide (LPS). Moreover, LYC increased A. muciniphila abundance, reduced intestinal inflammation and permeability, and upregulated the expression of the tight junction protein zonula occludens protein 1 (ZO-1) and occludin contents in the gut. Lastly, LYC inhibited LPS leakage and upregulated hepatic YAP1 expression, ultimately leading to the repair of DILI.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Chrysanthemum , Dioscorea , Lycium , Camundongos , Animais , Lipopolissacarídeos , Acetaminofen , Verrucomicrobia , Polissacarídeos/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico
17.
FASEB J ; 37(3): e22782, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36786721

RESUMO

Ischemia-reperfusion (I/R) injury is a crucial factor causing liver injury in the clinic. Recent research has confirmed that human adipose-derived stem cells (ADSCs) can differentiate into functional hepatocytes. However, the mechanism of the effects of ADSCs in the treatment of liver injury remains unclear. The characteristics of ADSCs were first identified, and exosome-derived ADSCs were isolated and characterized. The function and mechanism of action of miR-183 and arachidonate 5-lipoxygenase (ALOX5) were investigated by functional experiments in HL-7702 cells with I/R injury and in I/R rats. Our data disclosed that exosome release from ADSCs induced proliferation and inhibited apoptosis in HL-7702 cells with I/R injury. The effect of miR-183 was similar to that of exosomes derived from ADSCs. In addition, ALOX5, as a target gene of miR-183, was involved in the related functions of miR-183. Moreover, in vivo experiments confirmed that miR-183 and exosomes from ADSCs could improve liver injury in rats and inhibit the MAPK and NF-κB pathways. All of these findings demonstrate that exosomes derived from ADSCs have a significant protective effect on hepatic I/R injury by regulating the miR-183/ALOX5 axis, which might provide a therapeutic strategy for liver injury.


Assuntos
Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Traumatismo por Reperfusão , Humanos , Ratos , Animais , Linhagem Celular , MicroRNAs/genética , MicroRNAs/metabolismo , Exossomos/metabolismo , Araquidonato 5-Lipoxigenase/metabolismo , Células-Tronco Mesenquimais/metabolismo , Fígado/metabolismo , Reperfusão , Traumatismo por Reperfusão/metabolismo
18.
FASEB J ; 37(1): e22689, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36468767

RESUMO

Drug-induced liver injury (DILI) by acetaminophen (APAP) was one of the most challenging liver diseases. Wolfberry (Lycium barbarum L.), a traditional Chinese medicinal material and food supplement, has a potential effect on increasing the abundance of Akkermansia muciniphila (A. muciniphila) in mice colons. However, the effect and mechanism of wolfberry remain unclear in APAP-induced DILI. In this study, wolfberry promoted the proliferation of activated-A. muciniphila in vitro and in vivo. For the first time, we detected that the activated-A. muciniphila but not the killed-A. muciniphila increased the expression level of Yes-associated protein 1 (YAP1) in the liver and alleviated liver injury in APAP-induced DILI mice. Mechanically, A. muciniphila improved the intestinal mucosal barrier and reduced lipopolysaccharide (LPS) content in the liver, leading to the increased expression level of YAP1. Furthermore, wolfberry increased the A. muciniphila abundance in the colon and YAP1 expression in the liver from APAP-induced DILI mice, which promoted the recovery of APAP-induced liver injury. Meanwhile, wolfberry combination with A. muciniphila synergistically increased AKK abundance and YAP1 expression in the liver. Our research provides an innovative strategy to improve DILI.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Lycium , Camundongos , Animais , Acetaminofen/toxicidade , Verrucomicrobia
19.
Cell Commun Signal ; 22(1): 449, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327553

RESUMO

BACKGROUND: Diabetic retinopathy (DR) is a common microvascular complication of diabetes mellitus (DM) and a significant cause of acquired blindness in the working-age population worldwide. Aging is considered as an important risk factor for DR development. Macrophages in aged mice bear typical M2 marker proteins but simultaneously express a pro-inflammatory factor profile. This may explain why the level of intraocular inflammation does not decrease during proliferative diabetic retinopathy (PDR) despite the occurrence of neovascularization and fibrosis (M2 activation). α-Klotho (KL) was originally discovered as a soluble anti-aging factor, which is mainly expressed in kidney tubular epithelium, choroid plexus in the brain and secreted in the blood. However, the role of KL in DR pathophysiology has not been previously reported. METHODS: Type 1 (streptozotocin [STZ]-induced) and type 2 (a high-fat diet along with a low dose of STZ) diabetic mouse models were established and injected with or without KL adenovirus via the tail vein for 12 weeks. Vldlr-/- mice were injected intravitreally with or without soluble KL protein from P8 to P15. The retinal structure and function were analyzed by electroretinogram and optical coherence tomography. The neovascular lesions were analyzed by retinal flat mount and RPE flat mount. The senescence markers, macrophage morphology, and KL expression levels were detected by immunofluorescence staining. A cell model was constructed using RAW264.7 cells stimulated by 4-hydroxynonenal (4HNE) and transfected with or without KL adenovirus. The senescence-associated secretory phenotypes were detected by qRT-PCR. Senescence was detected by SA-ß-Gal staining. Serum, aqueous humor, and vitreous humor KL levels of proliferative diabetic retinopathy (PDR) patients were measured by enzyme-linked immunosorbent assay. Quantitative proteomics and bioinformatics were applied to predict the change of proteins and biological function after overexpression of KL in macrophages. The effects of KL on the HECTD1 binding to IRS1 were analyzed by bioinformatics, molecular docking, and Western Blot. RESULTS: Serum, aqueous humor, and vitreous humor KL levels were lower in patients with PDR than in those with cataracts. KL relieved the retinal structure damage, improved retina function, and inhibited retinal senescence in diabetic mice. KL administration attenuated the neovascular lesions in VLDLR-/- mice by decreasing the secretion of VEGFA and FGF2 from macrophages. KL also protected RAW264.7 cells from 4HNE-induced senescence. Additionally, it inhibited E3 ubiquitin ligase HECTD1 expression in both diabetic mouse peripheral blood mononuclear cells and 4HNE-treated RAW264.7 cells. KL inhibited HECTD1 binding to IRS1 and reduced the ubiquitination of IRS1. CONCLUSIONS: Macrophage aging is involved in DM-induced retinopathy. KL alleviates DM-induced retinal macrophage senescence by downregulating HECTD1 and decreasing IRS1 ubiquitination and degradation. Meanwhile, KL administration attenuated the neovascular lesions by altering the activation state of macrophages and decreasing the expression of VEGFA and FGF2.


Assuntos
Senescência Celular , Diabetes Mellitus Experimental , Retinopatia Diabética , Glucuronidase , Proteínas Klotho , Macrófagos , Animais , Macrófagos/metabolismo , Retinopatia Diabética/patologia , Retinopatia Diabética/metabolismo , Camundongos , Senescência Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/complicações , Glucuronidase/metabolismo , Glucuronidase/genética , Camundongos Endogâmicos C57BL , Masculino , Retina/metabolismo , Retina/patologia , Humanos , Células RAW 264.7
20.
Biomacromolecules ; 25(3): 2033-2040, 2024 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-38327086

RESUMO

The global plastic waste problem is pushing for the development of sustainable alternatives, encouraged by stringent regulations combined with increased environmental consciousness. In response, this study presents an industrial-scale proof of concept to produce self-standing, transparent, and flexible bioplastic films, offering a possible solution to plastic pollution and resource valorization. We achieve this by combining amyloid fibrils self-assembled from food waste with methylcellulose and glycerol. Specifically, soy whey and okara, two pivotal protein-rich byproducts of tofu manufacturing, emerge as sustainable and versatile precursors for amyloid fibril formation and bioplastic development. An exhaustive industrial-scale feasibility study involving the transformation of 500 L of soy whey into ∼1 km (27 kg) of bioplastic films underscores the potential of this technology. To extend the practicality of our approach, we further processed a running kilometer of film at the industrial scale into transparent windows for paper-based packaging. The mechanical properties and the water interactions of the novel film are tested and compared with those of commercially used plastic films. By pioneering the large-scale production of biodegradable bioplastics sourced from food byproducts, this work not only simultaneously addresses the dual challenges of plastic pollution and food waste but also practically demonstrates the feasibility of biopolymeric building block valorization for the development of sustainable materials in real-world scenarios.


Assuntos
Alimentos , Eliminação de Resíduos , Biopolímeros , Embalagem de Produtos , Plásticos
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