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1.
Clin Transl Med ; 14(3): e1636, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38533646

RESUMO

BACKGROUND: Inflammatory bowel diseases (IBDs) pose significant challenges in terms of treatment non-response, necessitating the development of novel therapeutic approaches. Although biological medicines that target TNF-α (tumour necrosis factor-α) have shown clinical success in some IBD patients, a substantial proportion still fails to respond. METHODS: We designed bispecific nanobodies (BsNbs) with the ability to simultaneously target human macrophage-expressed membrane TNF-α (hmTNF-α) and IL-23. Additionally, we fused the constant region of human IgG1 Fc (hIgG1 Fc) to BsNb to create BsNb-Fc.  Our study encompassed in vitro and in vivo characterization of BsNb and BsNb-Fc. RESULTS: BsNb-Fc exhibited an improved serum half-life, targeting capability and effector function than BsNb. It's demonstrated that BsNb-Fc exhibited superior anti-inflammatory effects compared to the anti-TNF-α mAb (infliximab, IFX) combined with anti-IL-12/IL-23p40 mAb (ustekinumab, UST) by Transwell co-culture assays. Notably, in murine models of acute colitis brought on by 2,4,6-trinitrobenzene sulfonic acid(TNBS) and dextran sulphate sodium (DSS), BsNb-Fc effectively alleviated colitis severity. Additionally, BsNb-Fc outperformed the IFX&UST combination in TNBS-induced colitis, significantly reducing colon inflammation in mice with colitis produced by TNBS and DSS. CONCLUSION: These findings highlight an enhanced efficacy and improved biostability of BsNb-Fc, suggesting its potential as a promising therapeutic option for IBD patients with insufficient response to TNF-α inhibition. KEY POINTS: A bispecific nanobody (BsNb) was created to target TNF-α and IL-23p19, exhibiting high affinity and remarkable stability. BsNb-Fc inhibited the release of cytokines in CD4+T cells during co-culture experiments. BsNb-Fc effectively alleviated colitis severity in mouse model with acute colitis induced by DSS or TNBS, outperforming the IFX&UST combination.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Camundongos , Humanos , Animais , Fator de Necrose Tumoral alfa , Subunidade p19 da Interleucina-23 , Inibidores do Fator de Necrose Tumoral/efeitos adversos , Colite/tratamento farmacológico , Doenças Inflamatórias Intestinais/tratamento farmacológico , Inflamação
2.
Gut ; 72(5): 882-895, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37015751

RESUMO

OBJECTIVE: Monocyte chemotactic protein-1-induced protein 1 (MCPIP1) is highly expressed in inflamed mucosa of inflammatory bowel disease (IBD) and negatively regulates immune response, while the underlying mechanisms regulating mucosal macrophage functions remain unknown. Here, we investigated the roles of MCPIP1 in modulating the differentiation and functions of intestinal macrophages in the pathogenesis of IBD. DESIGN: ScRNA-seq was used to cluster the monocyte/macrophage lineage from macrophage-specific Mcpip1-deficient (Mcpip1 ∆Mye) mice and Mcpip1 fl/fl littermates. The differentially expressed genes were confirmed by RNA-seq, luciferase assay, CUT&Tag assay and Western blotting. Effects of MCPIP1 and the activating transcription factor 3 (ATF3)-AP1S2 axis were assessed in patients with IBD. RESULTS: Mcpip1 ∆Mye mice developed more severe dextran sulfate sodium (DSS)-induced colitis characterised by an increase in macrophage migratory capacity and M1 macrophage polarisation but a decrease in the monocyte-to-macrophage maturation in gut mucosa compared with their littermates. ScRNA-seq unravelled a proinflammatory population (Ccr2+Il-1ß+Tlr2+Cx3cr1-Cd163-Mrc1-Ly6c+) of the monocyte/macrophage lineage from lamina propria CD11b+ cells and an arrest of Mcpip1 ∆Mye monocyte-to-macrophage maturation in an Atf3-Ap1s2 axis-dependent manner. Silencing of Ap1s2 or Atf3 markedly suppressed Mcpip1 ∆Mye macrophage migration, M1-like polarisation, and production of proinflammatory cytokines and chemokines. Notably, in vivo blockage of Ap1s2 ameliorated DSS-induced colitis in Mcpip1 ΔMye mice through enhancing intestinal macrophage maturation. Furthermore, MCPIP1, ATF3 and AP1S2 were highly expressed in inflamed mucosa of active patients with IBD and blockage of ATF3 or AP1S2 significantly suppressed IBD CD14+-derived M1-like macrophage polarisation and proinflammatory cytokine production. CONCLUSIONS: Macrophage-specific Mcpip1 deficiency polarises macrophages towards M1-like phenotype, arrests macrophage maturation and exacerbates intestinal inflammation in an Atf3-Ap1s2-dependent manner, thus providing novel mechanistic insight into intestinal macrophage functions during IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Ribonucleases , Animais , Camundongos , Fator 3 Ativador da Transcrição/genética , Fator 3 Ativador da Transcrição/metabolismo , Quimiocina CCL2/metabolismo , Colite/patologia , Sulfato de Dextrana/farmacologia , Inflamação/metabolismo , Mucosa Intestinal/metabolismo , Macrófagos , Camundongos Endogâmicos C57BL , Monócitos , Ribonucleases/metabolismo
3.
Gut Microbes ; 15(1): 2172668, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36729914

RESUMO

Neutrophils synergize with intestinal resident intraepithelial lymphocytes (IELs) to serve as the first-line defense and maintain intestinal homeostasis. However, the underlying mechanisms whereby neutrophils regulate IELs to inhibit intestinal inflammation are still not completely understood. Here, we found that depletion of neutrophils (especially CD177+ subset) caused expansion of colitogenic TCRγδ+CD8αα+ IELs, increased intestinal inflammation, and dysbiosis after dextran sulfate sodium exposure or Citrobacter rodentium infection in mice. scRNA-seq analysis revealed a pyroptosis-related gene signature and hyperresponsiveness to microbiota in TCRγδ+CD8αα+ IELs from colitic Cd177-/- mice. Microbiota-derived fumarate and its derivative dimethyl fumarate (DMF), as well as fumarate-producing microbiotas, decreased in the feces of colitic Cd177-/- mice. Elimination of dysbiosis by antibiotics treatment or co-housing procedure and DMF supplementation restrained TCRγδ+CD8αα+ IEL activation. Consistently, DMF significantly alleviated intestinal mucosal inflammation in mice through restricting gasdermin D (GSDMD)-induced pyroptosis of TCRγδ+CD8αα+ IELs. Therefore, our data reveal that neutrophils inhibit intestinal inflammation by promoting microbiota-derived DMF to regulate TCRγδ+CD8αα+ IEL activation in a GSDMD-mediated pyroptosis-dependent manner, and that DMF may serve as a therapeutic target for the management of intestinal inflammation.


Assuntos
Microbioma Gastrointestinal , Linfócitos Intraepiteliais , Camundongos , Animais , Fumarato de Dimetilo , Camundongos Knockout , Disbiose , Neutrófilos , Mucosa Intestinal , Inflamação , Camundongos Endogâmicos C57BL
4.
J Innate Immun ; : 1-21, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36273448

RESUMO

Monocyte chemotactic protein-1-induced protein-1 (MCPIP-1) is highly expressed in activated immune cells and negatively regulates immune responses, while the mechanisms underlying the immunoregulation of neutrophils in acute bacterial infection and liver injury remain elusive. Here, we examined the role of MCPIP-1 in regulating neutrophil functions during acute bacterial peritonitis and liver injury. Mice with myeloid cell-specific overexpression (McpipMye-tg) or knockout (McpipΔMye) of MCPIP-1 were generated. We found that reactive oxygen species and myeloperoxidase production, formation of neutrophil extracellular traps, and migratory capacity were deficient in McpipMye-tg neutrophils but enhanced in McpipΔMye neutrophils. The recruitment of neutrophils and pathogen clearance were markedly suppressed in McpipMye-tg mice following intraperitoneal infection with Salmonella typhimurium while intensified in McpipΔMye mice. Severe acute S. typhimurium-infected peritonitis and liver injury occurred in McpipMye-tg mice but were alleviated in McpipΔMye mice. RNA sequencing, RNA-binding protein immunoprecipitation and qPCR analysis revealed that MCPIP-1 downregulated the protective functions of neutrophils via degrading the mRNA of cold inducible RNA-binding protein. Consistently, MCPIP-1 was highly expressed in neutrophils of patients with acute infectious diseases, especially in those with liver injury. Collectively, we uncover that MCPIP-1 negatively regulates the antibacterial capacities of neutrophils, leading to exacerbating severe acute bacterial peritonitis and liver injury. It may serve as a candidate target for maintaining neutrophil homeostasis to control acute infectious diseases.

5.
Angew Chem Int Ed Engl ; 61(40): e202209496, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-35938902

RESUMO

Sensitive, rapid and low-cost nucleic acid detection is critical for controlling infectious pathogens. Here, we develop a ready-to-use and multimodal detection based on a rebuilding-free, ultrasensitive and selective strategy named dual hairpin ligation-induced isothermal amplification pro (DHLApro). Taking influenza A, influenza B, MERS-CoV, SARS-CoV-2 as model targets, we demonstrate DHLApro provides ≈zM level ultra-sensitivity, being equaling to 0.45 copy/µL in original sample. By simply changing the recognition module, a set of DHLApro components can be applied to a new target without performance loss. Moreover, DHLApro innovatively allows flexible logic/multiplex assay using one set of primer, for example, the "N pathogens-in-1" OR gate screening and accurate multi-channel multiplex assay. Compared with traditional methods, the cost of this logic/multiplex assay has been largely reduced and the cross-interference between the multiple primer sets is also avoided.


Assuntos
COVID-19 , Influenza Humana , Ácidos Nucleicos , COVID-19/diagnóstico , Genótipo , Humanos , Influenza Humana/diagnóstico , Lógica , Técnicas de Amplificação de Ácido Nucleico/métodos , SARS-CoV-2/genética , Sensibilidade e Especificidade
6.
J Autoimmun ; 132: 102872, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35926374

RESUMO

BACKGROUND & AIMS: As a susceptibility gene for human inflammatory bowel diseases (IBD), how avian erythroblastosis virus E26 oncogene homolog-1 (ETS-1) modulates intestinal mucosal immune response remains unclear. Here we studied the potential roles of ETS-1 in the pathogenesis of IBD. METHODS: ETS-1 expression was examined in IBD patients. CD45RBhighCD4+ T cell-transfer colitis, dextran sulfate sodium (DSS)-induced colitis, and azomethane (AOM)/DSS-induced colitis-associated cancer (CAC) models were constructed to probe the function of ETS-1 in vivo. RNA-sequencing of CD4+ T cells from Ets-1 transgenic (Tg) mice was performed to decipher the key differentially expressed genes. Adenovirus transduction was conducted to verify the therapeutic potentials of ETS-1 in vivo. RESULTS: ETS-1 expression was significantly increased in CD4+ T cells from active IBD patients compared with healthy controls, which was upregulated by TNF-α but markedly suppressed by anti-TNF-α mAb therapy. More severe colitis was observed in Rag1-/- mice reconstituted with Ets-1TgCD45RBhighCD4+ T cells or in Ets-1 Tg mice after DSS exposure compared with controls, characterized by higher TNF-α and IFN-γ expression in inflamed colon. Ets-1 Tg mice were more prone to develop AOM/DSS-induced CAC, and bone marrow chimeras further proved that lamina propria immune cells but not intestinal epithelial cells contributed to the development of colitis. RNA-sequencing and luciferase analysis revealed cold-inducible RNA-binding protein (CIRBP) as a functional target of ETS-1 to promote Th1 cell-driven immune response. Consistently, intraperitoneal administration of adenovirus-m-cirbp-shRNA ameliorated trinitrobenzene sulfonic acid (TNBS)-induced colitis of Ets-1 Tg mice. CONCLUSIONS: Our data identify that ETS-1 is highly expressed in IBD patients and promotes Th1-driven mucosal inflammation through CIRBP. CIRBP may serve as a novel therapeutic target for treatment of human IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Proteína Proto-Oncogênica c-ets-1 , Proteínas de Ligação a RNA , Células Th1 , Animais , Humanos , Camundongos , Colite/induzido quimicamente , Colite/genética , Colite/imunologia , Modelos Animais de Doenças , Inflamação , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Camundongos Transgênicos , Oncogenes , RNA , Proteínas de Ligação a RNA/genética , Células Th1/imunologia , Inibidores do Fator de Necrose Tumoral , Proteína Proto-Oncogênica c-ets-1/genética
7.
Drug Des Devel Ther ; 16: 2213-2227, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35860524

RESUMO

Purpose: To evaluate the effect of super-activated platelet lysate (sPL) on wound healing of tooth extraction sockets in rats. Methods: Rat models of the tooth extraction socket were established. Thirty-six rats were divided into control and sPL groups and sacrificed on days 7, 14, and 28 after tooth extraction. Bone formation in tooth extraction sockets were observed by microscopic computed tomography (micro-CT) and hematoxylin and eosin (HE) staining; osteoprotegerin (OPG), receptor activator of nuclear factor kappa-Β ligand (RANKL), interleukin 6(IL-6), and tumor necrosis factor-alpha (TNF-α) proteins were detected by immunohistochemistry; and chemokine and osteogenic gene expressions were detected by polymerase chain reaction (PCR). Results: sPL accelerated soft tissue wound healing in the extraction socket of rats. Micro-CT showed that the amount of bone formation and bone volume fraction were higher in the sPL group than the control 14 days after extraction. HE staining showed promotion of the formation of bony trabeculae by sPL in the apical third of the extraction socket 7 days after extraction and more mature and organized bony trabeculae in the sPL group than the control 14 days after extraction; mature bony trabeculae filling most of the fossa with lesser bone porosity in the socket in the sPL group than the control 28 days after extraction. Immunohistochemistry showed that sPL induced OPG expressions 7 and 14 days after tooth extraction but did not affect the RANKL expression while transiently promoting the IL-6 expression 7 days after extraction. PCR showed that sPL promoted chemokine expressions 7 and 14 days after extraction. The expressions of osteogenesis-related factors were higher in the sPL group than the control 7 and 28 days after extraction, while the opposite trend was observed 14 days after extraction. Conclusion: sPL has a transient pro-inflammatory effect and promotes soft tissue healing and bone formation during early wound healing of extraction sockets in rats.


Assuntos
Conservadores da Densidade Óssea , Interleucina-6 , Animais , Conservadores da Densidade Óssea/farmacologia , Osteogênese , Ratos , Extração Dentária/métodos , Alvéolo Dental , Cicatrização
8.
Clin Transl Med ; 12(3): e771, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35343079

RESUMO

G protein-coupled receptor 65 (GPR65), a susceptibility gene for inflammatory bowel diseases (IBD), has been identified to promote Th17 cell pathogenicity and induce T cell apoptosis. However, the potential role of GPR65 in modulating CD4+ T cell immune responses in the pathogenesis of IBD stills not entirely understood. Here, we displayed that GPR65 expression was increased in inflamed intestinal mucosa of IBD patients and positively associated with disease activity. It was expressed in CD4+ T cells and robustly upregulated through the TNF-α-caspase 3/8 signalling pathway. Ectopic expression of GPR65 significantly promoted the differentiation of peripheral blood (PB) CD4+ T cells from IBD patients and HC to Th1 and Th17 cells in vitro. Importantly, conditional knockout of Gpr65 in CD4+ T cells ameliorated trinitrobenzene sulfonic acid (TNBS)-induced acute murine colitis and a chronic colitis in Rag1-/- mice reconstituted with CD45RBhigh CD4+ T cells in vivo, characterised by attenuated Th1 and Th17 cell immune response in colon mucosa and decreased infiltration of CD4+ T cells, neutrophils and macrophages. RNA-seq analysis of Gpr65ΔCD4 and Gpr65flx/flx CD4+ T cells revealed that NUAK family kinase 2 (Nuak2) acts as a functional target of Gpr65 to restrict Th1 and Th17 cell immune response. Mechanistically, GPR65 deficiency promoted NUAK2 expression via the cAMP-PKA-C-Raf-ERK1/2-LKB1-mediated signalling pathway. Consistently, silencing of Nuak2 facilitated the differentiation of Gpr65ΔCD4 and Gpr65flx/flx CD4+ T cells into Th1 and Th17 cells. Therefore, our data point out that GPR65 promotes Th1 and Th17 cell immune response and intestinal mucosal inflammation by suppressing NUAK2 expression, and that targeting GPR65 and NUAK2 in CD4+ T cells may represent a novel therapeutic approach for IBD.


Assuntos
Células Th1 , Células Th17 , Animais , Diferenciação Celular/genética , Humanos , Inflamação/metabolismo , Inflamação/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Camundongos , Proteínas Serina-Treonina Quinases , Receptores Acoplados a Proteínas G , Células Th1/patologia , Células Th17/patologia
9.
J Colloid Interface Sci ; 608(Pt 2): 1782-1791, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34743047

RESUMO

TiNb2O7 (TNO) as a promising candidate anode for lithium-ion batteries (LIBs) shows obvious advantages in terms of specific capacity and safety, but which undergoes the intrinsic poor electrical and ionic conductivity. Herein, we propose a simple synthesis strategy of mesoporous TNO via a polymeric surfactant-mediated evaporation-induced sol-gel method, using polyvinylpyrrolidone (PVP) with different molecular weights (average Mw: 10000/58000/1300000) as the regulating agent, which greatly affects the lithium storage performance of the as-prepared TNO. The optimized TNO (i.e., PVP of 58000) delivers a high reversible capacity of 303.1 mAh/g at 1 C, with a retention rate of 73.4% (222.5 mAh/g) after 300 cycles. Even at 5 C, a high reversible capacity of 185.6 mAh/g can be achieved, with a retention rate of 72.3% after 1000 cycles. The superior lithium storage behavior is attributed to the fine mesoporous framework consisting of interconnected TNO nanocrystallites with high specific surface area and high mesoporosity, which greatly increases the active sites, improves the Li+ diffusion kinetics and alleviates volume fluctuation induced by the repetitive Li+ insertion-extraction processes.

10.
J Colloid Interface Sci ; 607(Pt 1): 171-180, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34500416

RESUMO

Metal oxides are prospective alternative anode materials to the commercial graphite for lithium ion batteries (LIBs), while their practical application is seriously hampered by their poor conductivities and large volume changes. Herein, we report the controllable synthesis of amorphous/crystalline MnCo2Ox nanoparticles within porous carbon nanofibers (marked as MCO@CNFs) through a facile electrospinning strategy and subsequent annealing reactions. The phase structures from Co/MnOX to amorphous MnCo2Ox and crystalline MnCo2O4.5 can be readily tuned by thermal reduction/oxidation under controlled atmosphere and temperature. When examined as anode for LIBs, the optimized MCO@CNFs delivers a high stable capacity of 780.3 mA h g-1 at 200 mA g-1 after 250 cycles, which is attributed to the synergistic effect of the distinctive amorphous structure and defective carbon nanofiber matrices. Specifically, the amorphous structure with rich defects offers more reactive sites and multiple pathways for the Li+ diffusion, while carbon hybridization sufficiently improves the electrode conductivities as well as buffers the volume changes. More importantly, we demonstrate a convenient synthesis strategy to control the metal-to-oxide structure evolution within carbon matrices, which is of great importance in exploring high-performance electrodes for next generation LIBs.

11.
Gut Microbes ; 13(1): 1968257, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34494943

RESUMO

Host-microbial cross-talk plays a crucial role in maintenance of gut homeostasis. However, how microbiota-derived metabolites, e.g., butyrate, regulate functions of neutrophils in the pathogenesis of inflammatory bowel disease (IBD) remains elusive. We sought to investigate the effects of butyrate on IBD neutrophils and elucidate the therapeutic potential in regulating mucosal inflammation. Peripheral neutrophils were isolated from IBD patients and healthy donors, and profiles of proinflammatory cytokines and chemokines were determined by qRT-PCR and ELISA, respectively. The migration and release of neutrophil extracellular traps (NETs) were studied by a Transwell model and immunofluorescence, respectively. The in vivo role of butyrate in regulating IBD neutrophils was evaluated in a DSS-induced colitis model in mice. We found that butyrate significantly inhibited IBD neutrophils to produce proinflammatory cytokines, chemokines, and calprotectins. Blockade of GPCR signaling with pertussis toxin (PTX) did not interfere the effects whereas pan-histone deacetylase (HDAC) inhibitor, trichostatin A (TSA) effectively mimicked the role of butyrate. Furthermore, in vitro studies confirmed that butyrate suppressed neutrophil migration and formation of NETs from both CD and UC patients. RNA sequencing analysis revealed that the immunomodulatory effects of butyrate on IBD neutrophils were involved in leukocyte activation, regulation of innate immune response and response to oxidative stress. Consistently, oral administration of butyrate markedly ameliorated mucosal inflammation in DSS-induced murine colitis through inhibition of neutrophil-associated immune responses such as proinflammatory mediators and NET formation. Our data thus reveal that butyrate constrains neutrophil functions and may serve as a novel therapeutic potential in the treatment of IBD.


Assuntos
Butiratos/farmacologia , Armadilhas Extracelulares/imunologia , Doenças Inflamatórias Intestinais/tratamento farmacológico , Mucosa Intestinal/patologia , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Animais , Butiratos/metabolismo , Células Cultivadas , Colite/tratamento farmacológico , Colite/microbiologia , Colite/patologia , Citocinas/análise , Modelos Animais de Doenças , Microbioma Gastrointestinal/fisiologia , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Homeostase/imunologia , Interações entre Hospedeiro e Microrganismos/fisiologia , Humanos , Ácidos Hidroxâmicos/farmacologia , Imunidade Inata/imunologia , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/imunologia , Toxina Pertussis/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores
12.
Plant Physiol Biochem ; 166: 66-77, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34090122

RESUMO

Alkali stress is an extreme complex stress type, which exerts negative effects on plants via chemical destruction, osmotic stress, ion injury, nutrient deficiency, and oxygen deficiency. Soil alkalization has produced severe problems in some area, while plant alkali tolerance is poorly understood. Sunflower (Helianthus annuus L.) is an important oilseed crop with strong alkali tolerance. Here we exposed sunflower plants to alkali stress (NaHCO3/Na2CO3 = 9:1; pH 8.7) for whole life cycle. We applied transcriptomics, metabolomics, lipidomics and phytohormone analysis to elucidate the alkali tolerance mechanism of sunflower plant. Lipidomic analysis showed that alkali stress enhanced accumulation of saccharolipids and glycerolipids and lowered the accumulation of glycerophospholipids in sunflower seeds, indicating that alkali stress can change the lipid components of sunflower seeds, and that cultivating sunflower plants on alkalized farmlands will change the quality of sunflower seed oils. In addition, alkali stress downregulated expression of two rate-controlling genes of glycolysis in the leaves of sunflower but upregulated their expression in the roots. Enhanced glycolysis process provided more carbon sources and energy for alkali stress response of sunflower roots. Under alkali stress, accumulation of many fatty acids, amino acids, carbohydrates, and organic acids was greatly stimulated in sunflower roots. Alkali stress enhanced ACC, GA1, and ABA concentrations in the leaves but not in the roots, however, alkali stress elevated accumulation of BR (typhasterol) and CTK (Isopentenyladenosine) in the roots. We propose that multiple phytohormones and bioactive molecules interact to mediate alkali tolerance of sunflower.


Assuntos
Helianthus , Álcalis , Folhas de Planta , Raízes de Plantas , Solo
13.
Plant Cell Rep ; 40(7): 1181-1197, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33945005

RESUMO

KEY MESSAGE: Puccinellia tenuiflora was domesticated for two years by growing it under non-saline conditions, providing epigenetic and biochemical insights into the initial domestication of extreme halophytes. Some halophytes have economic value as crop species. The domestication of halophytes may offer hope in solving the problem of soil salinization. We domesticated a wild halophyte, Puccinellia tenuiflora, for two years by growing it under non-saline conditions in a greenhouse and used re-sequencing, genome-wide DNA methylation, biochemical, and transcriptome analyses to uncover the mechanisms underlying alterations in the halophyte's tolerance to saline following domestication. Our results showed that non-saline domestication altered the methylation status for a number of genes and transposable elements, resulting in a much higher frequency of hypomethylation than hypermethylation. These modifications to DNA methylation were observed in many critical salinity-tolerance genes, particularly their promoter regions or transcriptional start sites. Twenty-nine potassium channel genes were hypomethylated and three were hypermethylated, suggesting that the DNA methylation status of potassium channel genes was influenced by domestication. The accelerated uptake of potassium is a major salinity tolerance characteristic of P. tenuiflora. We propose that modifications to the DNA methylation of potassium channel genes may be associated with the development of salinity tolerance in this species. By assessing whether non-saline domestication could change the salinity tolerance of P. tenuiflora, we demonstrated that non-saline domesticated plants are less tolerant to saline, which may be attributable to altered sucrose metabolism. DNA methylation and transposable elements may, therefore, be integrated into an environment-sensitive molecular engine that promotes the rapid domestication of P. tenuiflora to enable its use as a crop plant.


Assuntos
Metilação de DNA , Poaceae/genética , Tolerância ao Sal/genética , Plantas Tolerantes a Sal/genética , China , Elementos de DNA Transponíveis , Domesticação , Epigênese Genética , Regulação da Expressão Gênica de Plantas , Estudo de Associação Genômica Ampla , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Proteínas de Plantas/genética , Poaceae/fisiologia , Polimorfismo de Nucleotídeo Único , Potássio/metabolismo
14.
Front Plant Sci ; 12: 649001, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33968105

RESUMO

Halophytes and glycophytes exhibit clear differences in their tolerance to high levels of salinity. The genetic mechanisms underlying this differentiation, however, remain unclear. To unveil these mechanisms, we surveyed the evolution of salinity-tolerant gene families through comparative genomic analyses between the model halophyte Puccinellia tenuiflora and glycophytic Gramineae plants, and compared their transcriptional and physiological responses to salinity stress. Under salinity stress, the K+ concentration in the root was slightly enhanced in P. tenuiflora, but it was greatly reduced in the glycophytic Gramineae plants, which provided a physiological explanation for differences in salinity tolerance between P. tenuiflora and these glycophytes. Interestingly, several K+ uptake gene families from P. tenuiflora experienced family expansion and positive selection during evolutionary history. This gene family expansion and the elevated expression of K+ uptake genes accelerated K+ accumulation and decreased Na+ toxicity in P. tenuiflora roots under salinity stress. Positively selected P. tenuiflora K+ uptake genes may have evolved new functions that contributed to development of P. tenuiflora salinity tolerance. In addition, the expansion of the gene families involved in pentose phosphate pathway, sucrose biosynthesis, and flavonoid biosynthesis assisted the adaptation of P. tenuiflora to survival under high salinity conditions.

15.
Front Microbiol ; 12: 636788, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33746929

RESUMO

The global increase of community-associated (CA) infections with methicillin-resistant Staphylococcus aureus (MRSA) is a major healthcare problem. Although sequence type (ST) 398 MRSA was first described as a livestock-associated (LA) lineage, human-adapted MRSA (HO-MRSA) ST398 without livestock contact has subsequently been reported from China in our previous study and other later research. The proportion of ST398 HO-MRSA has also remarkably increased in recent years in China. Based on 3878 S. aureus isolates that were collected in a general hospital between 2008 and 2018, we identified 56 ST398 HO-MRSA isolates. The four early appearing isolates of them have been sequenced by whole-genome sequencing (WGS) in our previous study. Here, by usage of WGS on the later-appearing 52 isolates and analyzing the phylogenetic dynamics of the linage, we found that 50 isolates clustered together with the former 4 isolates, making it a main clade out of MSSA clones and other MRSA clones, although ST398 HO-MRSA evolved with multiple origins. Drug resistance and virulence gene analysis based on the WGS data demonstrated that ST398 HO-MRSA main clade exhibited a similar pattern in both parts. Furthermore, they all carried a conserved variant of prophage 3 to guarantee virulence and a short SCCmec type V element of class D to maintain considerable lower methicillin resistance. Further phenotypical research verified that the epidemic HO-MRSA ST398 displayed enhanced biofilm formation ability when keeping high virulence. The dual advantages of virulence and biofilm formation in the HO-MRSA ST398 subtype promote their fitness in the community and even in the healthcare environment, which poses a serious threat in clinical S. aureus infections. Therefore, further surveillance is required to prevent and control the problematic public health impact of HO-MRSA ST398 in the future.

16.
Clin Transl Med ; 11(2): e334, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33634990

RESUMO

BACKGROUND: Cyclosporine A (CsA) is routinely used to treat patients with steroid-refractory acute severe ulcerative colitis (ASUC). Here, we studied the underlying mechanisms of CsA-mediated alleviation in ASUC patients. METHODS: Neutrophil functions including expression of cytokines, apoptosis, and migration were measured by qRT-PCR, flow cytometry, and Transwell assay. Dynamic changes of glycolysis and tricarboxylic acid (TCA) cycle were measured by a Seahorse extracellular flux analyzer. Gene differences were determined and verified by RNA sequencing, qRT-PCR, and Western blotting. Small interfering RNA and inhibitors were used to knock down Sirtuin 6 (SIRT6) in HL-60 cells and block expression of SIRT6, hypoxia-inducible factor-1α (HIF-1α), and pyruvate dehydrogenase lipoamide kinase isozyme 4 (PDK4) in neutrophils. RESULTS: We found that HIF-1α expression and glycolysis significantly increased, while the release of IL-8, myeloperoxidase (MPO) and reactive oxygen species (ROS), the apoptosis, and ability of migration markedly decreased in neutrophils of ASUC patients who responded to CsA (Response group) compared with those who did not respond to CsA (Nonresponse group). We also observed that CsA-induced functional alternation of neutrophils was initiated through suppressing SIRT6 expression, which is responsible for expression of the downstream signaling molecules (e.g., HIF-1α, PFKFB3) and PDK4 ubiquitination, leading to fueling neutrophil glycolysis and TCA cycle. Furthermore, blockage of SIRT6 signaling demonstrated to be the same functional changes as CsA to decrease the migration of neutrophils. CONCLUSIONS: The data reveal a novel mechanism of CsA in alleviating ASUC by promoting neutrophil HIF-1α expression and restricting excessive neutrophil activation in a SIRT6-HIF-1α-glycolysis axis, suggesting SIRT6 as a candidate target for maintaining mucosal homeostasis and treating intestinal inflammation.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Ciclosporina/uso terapêutico , Glicólise/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imunossupressores/uso terapêutico , Neutrófilos/efeitos dos fármacos , Sirtuínas/metabolismo , Adulto , Idoso , Apoptose/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Reação em Cadeia da Polimerase , Adulto Jovem
17.
Commun Biol ; 4(1): 213, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33594251

RESUMO

The mucosa microenvironment is critical for intestinal stem cell self-renewal and reconstruction of the epithelial barrier in inflammatory bowel disease (IBD), where the mechanisms underlying cross-talk between intestinal crypts and the microenvironment remain unclear. Here, we firstly identified miR-494-3p as an important protector in colitis. miR-494-3p levels were decreased and negatively correlated with the severity in human IBD samples, as well as in colitis mice. In colitis crypts, a notable cytokine-cytokine receptor, miR-494-3p-targeted EDA2R and the ligand EDA-A2, suppressed colonic stemness and epithelial repair by inhibiting ß-catenin/c-Myc. In differentiated IECs, miR-494-3p inhibits macrophage recruitment, M1 activation and EDA-A2 secretion by targeting IKKß/NF-κB in colitis. A miR-494-3p agomir system notably ameliorated the severity of colonic colitis in vivo. Collectively, our findings uncover a miR-494-3p-mediated cross-talk mechanism by which macrophage-induced intestinal stem cell impairment aggravates intestinal inflammation.


Assuntos
Colite/metabolismo , Colo/metabolismo , Ectodisplasinas/metabolismo , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , MicroRNAs/metabolismo , Comunicação Parácrina , Células-Tronco/metabolismo , Receptor Xedar/metabolismo , Animais , Antagomirs/administração & dosagem , Células Cultivadas , Quimiotaxia , Colite/genética , Colite/patologia , Colite/prevenção & controle , Colo/patologia , Modelos Animais de Doenças , Ectodisplasinas/genética , Humanos , Quinase I-kappa B/metabolismo , Mucosa Intestinal/patologia , Ativação de Macrófagos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Organoides , Nicho de Células-Tronco , Células-Tronco/patologia , Via de Sinalização Wnt , Receptor Xedar/genética
18.
J Colloid Interface Sci ; 586: 663-672, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33198981

RESUMO

Transition metal oxides/selenides as anodes for sodium-ion batteries (SIBs) suffer from the insufficient conductivity and large volumetric expansion, which leads to the poor electrochemical performance. To address these issues, we herein demonstrate a facile selenization method to enhance the sodium storage capability of CoMoO4 nanoparticles which are encapsulated into the electrospun carbon nanofibers (CMO@carbon for short). The partially and fully selenized CoMoO4 within carbon nanofibers (denote as CMOS@carbon and CMS@carbon, respectively) can be readily obtained by controlling the annealing temperature (at 400 and 600 °C, correspondingly). When examined as anode materials for SIBs, the CMOS@carbon nanofibers display an outstanding electrochemical performance with a higher reversible capacity of 396 mA h g-1 after 200 cycles at 0.2 A g-1 and a high-rate capacity of 365 mA h g-1 at 2 A g-1, as compared with the CMO@carbon and CMS@carbon counterparts. The enhanced sodium storage performance of the CMOS@carbon can be owing to the partial selenization of the CoMoO4 nanoparticles which are rooted into the porous electrospun carbon nanofibers, thus endowing them with superior ionic/electronic charge transfer efficiencies and a cushion against the electrode pulverization during cycling. Moreover, this work proposed a useful strategy to enhance the sodium storage performance of metal oxides via controlled selenization, which is promising for exploiting the advanced anode materials for SIBs.

19.
Drug Des Devel Ther ; 14: 5535-5543, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33364749

RESUMO

PURPOSE: The aim of the present study was to evaluate the expression of inflammasome and cytokine on experimental periodontitis with super activated platelet lysate (SPL) in rats. METHODS: Periodontitis was induced by submerging cotton ligatures on the right side of the maxillary second molar in 36 Wistar rats. The rats were divided into 3 groups randomly: the rats received no treatment (control group); local injection with sterile saline (ligature+saline group) and local injection with SPL (ligature+SPL group). After treatments, the alveolar bone level and inflammation of periodontal tissue were evaluated by micro-computed tomography (micro-CT) scanning and histological examination, respectively. The expression of inflammasome and cytokine was evaluated by real-time quantitative polymerase chain reaction (RT-qPCR) assay. RESULTS: Compared with the control group, the bone loss significantly increased by 0.9 mm in the ligature+saline group and 0.4 mm in the ligature+SPL group (P < 0.001). 0.5 mm reduction in the bone loss was founded in the ligature+SPL group compared with the ligature+saline group (P < 0.001). The gene expression of CCL2, CXCL2, IL-6, IL-18, IL-1α, IL-1ß, CXCL10, CXCL16, CCL5 was significantly reduced in the ligature+SPL group compared with the ligature+saline group (P < 0.05). Compared with the ligature+saline group, the expression for inflammasome NLRP3, AIM2, CASP1 was both downregulated in the ligature+SPL group (P < 0.05). CONCLUSION: Our present study demonstrated local injection of SPL regulated the expression of inflammasome and cytokine and had a visible effect of relieving inflammation in the experimental periodontitis in rats.


Assuntos
Plaquetas/metabolismo , Citocinas/metabolismo , Inflamassomos/metabolismo , Periodontite/metabolismo , Animais , Citocinas/genética , Modelos Animais de Doenças , Feminino , Inflamassomos/genética , Periodontite/diagnóstico por imagem , Ratos , Ratos Wistar , Microtomografia por Raio-X
20.
Nanoscale ; 12(37): 19420-19428, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32955069

RESUMO

The low activity of nanozymes, which work as an alternative to natural enzymes, limits their applications in the fabrication of biosensors, drawing increasing attention aimed at improving their catalytic capacity. In this work, the peroxidase-like activity of MoS2 nanosheets (NSs) was dramatically enhanced through DNA modification, and was 4.3-times higher than that of bare MoS2 NSs. Such an enhancement of catalytic activity was mainly ascribed to the increased affinity of the DNA/MoS2 NSs toward the substrate, TMB, further accelerating electron transfer from TMB to H2O2. On the basis of DNA-tuned MoS2 NS nanozyme activity, a colorimetric sensing platform was developed for the facile detection of carcinoembryonic antigen (CEA) in a sensitive manner. Interestingly, a convenient, affordable, and instrument-free portable test kit was fabricated to visually monitor CEA via rooting the aptamer/MoS2 NS system into an agarose hydrogel. Importantly, our work illuminates the feasibility of using DNA to enhance the catalysis of nanozymes and their application potential in the label-free, portable, and visual detection of aptamer-targeted biomolecules.


Assuntos
Técnicas Biossensoriais , Colorimetria , DNA , Dissulfetos , Peróxido de Hidrogênio , Molibdênio , Peroxidase , Peroxidases
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