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1.
Nature ; 602(7898): 657-663, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35016194

RESUMO

The SARS-CoV-2 B.1.1.529 (Omicron) variant contains 15 mutations of the receptor-binding domain (RBD). How Omicron evades RBD-targeted neutralizing antibodies requires immediate investigation. Here we use high-throughput yeast display screening1,2 to determine the profiles of RBD escaping mutations for 247 human anti-RBD neutralizing antibodies and show that the neutralizing antibodies can be classified by unsupervised clustering into six epitope groups (A-F)-a grouping that is highly concordant with knowledge-based structural classifications3-5. Various single mutations of Omicron can impair neutralizing antibodies of different epitope groups. Specifically, neutralizing antibodies in groups A-D, the epitopes of which overlap with the ACE2-binding motif, are largely escaped by K417N, G446S, E484A and Q493R. Antibodies in group E (for example, S309)6 and group F (for example, CR3022)7, which often exhibit broad sarbecovirus neutralizing activity, are less affected by Omicron, but a subset of neutralizing antibodies are still escaped by G339D, N440K and S371L. Furthermore, Omicron pseudovirus neutralization showed that neutralizing antibodies that sustained single mutations could also be escaped, owing to multiple synergetic mutations on their epitopes. In total, over 85% of the tested neutralizing antibodies were escaped by Omicron. With regard to neutralizing-antibody-based drugs, the neutralization potency of LY-CoV016, LY-CoV555, REGN10933, REGN10987, AZD1061, AZD8895 and BRII-196 was greatly undermined by Omicron, whereas VIR-7831 and DXP-604 still functioned at a reduced efficacy. Together, our data suggest that infection with Omicron would result in considerable humoral immune evasion, and that neutralizing antibodies targeting the sarbecovirus conserved region will remain most effective. Our results inform the development of antibody-based drugs and vaccines against Omicron and future variants.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Evasão da Resposta Imune/imunologia , Testes de Neutralização , SARS-CoV-2/imunologia , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/classificação , Anticorpos Antivirais/classificação , COVID-19/imunologia , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Células Cultivadas , Convalescença , Epitopos de Linfócito B/química , Epitopos de Linfócito B/imunologia , Humanos , Soros Imunes/imunologia , Modelos Moleculares , Mutação , SARS-CoV-2/química , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo
2.
Nature ; 608(7923): 593-602, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35714668

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron sublineages BA.2.12.1, BA.4 and BA.5 exhibit higher transmissibility than the BA.2 lineage1. The receptor binding and immune-evasion capability of these recently emerged variants require immediate investigation. Here, coupled with structural comparisons of the spike proteins, we show that BA.2.12.1, BA.4 and BA.5 (BA.4 and BA.5 are hereafter referred collectively to as BA.4/BA.5) exhibit similar binding affinities to BA.2 for the angiotensin-converting enzyme 2 (ACE2) receptor. Of note, BA.2.12.1 and BA.4/BA.5 display increased evasion of neutralizing antibodies compared with BA.2 against plasma from triple-vaccinated individuals or from individuals who developed a BA.1 infection after vaccination. To delineate the underlying antibody-evasion mechanism, we determined the escape mutation profiles2, epitope distribution3 and Omicron-neutralization efficiency of 1,640 neutralizing antibodies directed against the receptor-binding domain of the viral spike protein, including 614 antibodies isolated from people who had recovered from BA.1 infection. BA.1 infection after vaccination predominantly recalls humoral immune memory directed against ancestral (hereafter referred to as wild-type (WT)) SARS-CoV-2 spike protein. The resulting elicited antibodies could neutralize both WT SARS-CoV-2 and BA.1 and are enriched on epitopes on spike that do not bind ACE2. However, most of these cross-reactive neutralizing antibodies are evaded by spike mutants L452Q, L452R and F486V. BA.1 infection can also induce new clones of BA.1-specific antibodies that potently neutralize BA.1. Nevertheless, these neutralizing antibodies are largely evaded by BA.2 and BA.4/BA.5 owing to D405N and F486V mutations, and react weakly to pre-Omicron variants, exhibiting narrow neutralization breadths. The therapeutic neutralizing antibodies bebtelovimab4 and cilgavimab5 can effectively neutralize BA.2.12.1 and BA.4/BA.5, whereas the S371F, D405N and R408S mutations undermine most broadly sarbecovirus-neutralizing antibodies. Together, our results indicate that Omicron may evolve mutations to evade the humoral immunity elicited by BA.1 infection, suggesting that BA.1-derived vaccine boosters may not achieve broad-spectrum protection against new Omicron variants.


Assuntos
Anticorpos Antivirais , Deriva e Deslocamento Antigênicos , COVID-19 , Epitopos de Linfócito B , Tolerância Imunológica , Mutação , SARS-CoV-2 , Enzima de Conversão de Angiotensina 2/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Deriva e Deslocamento Antigênicos/genética , Deriva e Deslocamento Antigênicos/imunologia , COVID-19/imunologia , COVID-19/transmissão , COVID-19/virologia , Vacinas contra COVID-19/imunologia , Epitopos de Linfócito B/química , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/imunologia , Humanos , Imunidade Humoral , Imunização Secundária , Testes de Neutralização , SARS-CoV-2/classificação , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo
3.
J Virol ; 98(3): e0191523, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38334327

RESUMO

As an intrinsic cellular mechanism responsible for the internalization of extracellular ligands and membrane components, caveolae-mediated endocytosis (CavME) is also exploited by certain pathogens for endocytic entry [e.g., Newcastle disease virus (NDV) of paramyxovirus]. However, the molecular mechanisms of NDV-induced CavME remain poorly understood. Herein, we demonstrate that sialic acid-containing gangliosides, rather than glycoproteins, were utilized by NDV as receptors to initiate the endocytic entry of NDV into HD11 cells. The binding of NDV to gangliosides induced the activation of a non-receptor tyrosine kinase, Src, leading to the phosphorylation of caveolin-1 (Cav1) and dynamin-2 (Dyn2), which contributed to the endocytic entry of NDV. Moreover, an inoculation of cells with NDV-induced actin cytoskeletal rearrangement through Src to facilitate NDV entry via endocytosis and direct fusion with the plasma membrane. Subsequently, unique members of the Rho GTPases family, RhoA and Cdc42, were activated by NDV in a Src-dependent manner. Further analyses revealed that RhoA and Cdc42 regulated the activities of specific effectors, cofilin and myosin regulatory light chain 2, responsible for actin cytoskeleton rearrangement, through diverse intracellular signaling cascades. Taken together, our results suggest that an inoculation of NDV-induced Src-mediated cellular activation by binding to ganglioside receptors. This process orchestrated NDV endocytic entry by modulating the activities of caveolae-associated Cav1 and Dyn2, as well as specific Rho GTPases and downstream effectors. IMPORTANCE: In general, it is known that the paramyxovirus gains access to host cells through direct penetration at the plasma membrane; however, emerging evidence suggests more complex entry mechanisms for paramyxoviruses. The endocytic entry of Newcastle disease virus (NDV), a representative member of the paramyxovirus family, into multiple types of cells has been recently reported. Herein, we demonstrate the binding of NDV to induce ganglioside-activated Src signaling, which is responsible for the endocytic entry of NDV through caveolae-mediated endocytosis. This process involved Src-dependent activation of the caveolae-associated Cav1 and Dyn2, as well as specific Rho GTPase and downstream effectors, thereby orchestrating the endocytic entry process of NDV. Our findings uncover a novel molecular mechanism of endocytic entry of NDV into host cells and provide novel insight into paramyxovirus mechanisms of entry.


Assuntos
Macrófagos , Doença de Newcastle , Vírus da Doença de Newcastle , Transdução de Sinais , Internalização do Vírus , Animais , Endocitose , Gangliosídeos/metabolismo , Macrófagos/metabolismo , Macrófagos/virologia , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/fisiologia , Proteínas rho de Ligação ao GTP/metabolismo
4.
Mol Cell ; 67(6): 1049-1058.e6, 2017 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-28938092

RESUMO

Recent studies indicate that even a homogeneous population of cells display heterogeneity in gene expression and response to environmental stimuli. Although promoter structure critically influences the cell-to-cell variation of gene expression in bacteria and lower eukaryotes, it remains unclear what controls the gene expression noise in mammals. Here we report that CTCF decreases cell-to-cell variation of expression by stabilizing enhancer-promoter interaction. We show that CTCF binding sites are interwoven with enhancers within topologically associated domains (TADs) and a positive correlation is found between CTCF binding and the activity of the associated enhancers. Deletion of CTCF sites compromises enhancer-promoter interactions. Using single-cell flow cytometry and single-molecule RNA-FISH assays, we demonstrate that knocking down of CTCF or deletion of a CTCF binding site results in increased cell-to-cell variation of gene expression, indicating that long-range promoter-enhancer interaction mediated by CTCF plays important roles in controlling the cell-to-cell variation of gene expression in mammalian cells.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica , Regiões Promotoras Genéticas , Proteínas Repressoras/metabolismo , Animais , Sítios de Ligação , Fator de Ligação a CCCTC , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Feminino , Citometria de Fluxo , Sequenciamento de Nucleotídeos em Larga Escala , Hibridização in Situ Fluorescente , Camundongos Endogâmicos C57BL , Ligação Proteica , Interferência de RNA , Proteínas Repressoras/genética , Análise de Célula Única , Transcrição Gênica , Ativação Transcricional , Transfecção
5.
Stroke ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920054

RESUMO

BACKGROUND: Dendritic cells (DCs) regulate the immune response associated with T lymphocytes, but their role in stroke remains unclear. In this study, we investigated the causal relationship between DCs and T-cell response in intracerebral hemorrhage (ICH) by focusing on TLRs (toll-like receptors) that may modulate the function of DCs. METHODS: We studied the effects of TLR4, TLR2, and TLR9 on DC-mediated T-cell response and the outcomes of ICH using male C57BL/6 and CD11c-DTx (diphtheria toxin) receptor mice. We administered specific agents intraperitoneally or orally and evaluated the results using flow cytometry, real-time polymerase chain reaction, Western blotting, immunofluorescence staining, histopathology, and behavioral tests. RESULTS: TLR4 and TLR2 activation induces DC maturation and reduces the ratio of regulatory T to T-helper 17 cells in the brain and periphery after ICH. When either of these receptors is activated, it can worsen neuroinflammation and exacerbate ICH outcomes. TLR9 also promotes DC maturation, stabilizing the number of DCs, particularly conventional DCs. TLR9 has the opposite effects on regulatory T/T-helper 17 balance, neuroinflammation, and ICH outcomes compared with TLR4 and TLR2. Upon stimulation, TLR4 and TLR9 may achieve these effects through the p38-MAPK (p38-mitogen-activated protein kinase)/MyD88 (myeloid differentiation primary response gene 88) and indoleamine 2,3-dioxygenase 1 (IDO1)/GCN2 (general control nonderepressible 2) signaling pathways, respectively. DCs act as intermediaries for TLR-mediated T-cell response. CONCLUSIONS: TLR-mediated opposing effects of DCs on T-cell response may provide novel strategies to treat ICH.

6.
J Org Chem ; 89(7): 4774-4783, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38506335

RESUMO

A facile and efficient copper-catalyzed domino-double annulation strategy was developed from easily accessible o-aminobenzamides and 2-iodoisothiocyanates, which affords a direct pathway for the synthesis of tetracyclic fused 12H-benzo[4,5]thiazolo[2,3-b]quinazolin-12-ones in moderate to good yields without the addition of ligands, bases, and external oxidants. The reaction involves a C-N bond cleavage and the formation of a C-N/C-S bond in one step with the advantages of using an inexpensive copper catalyst and easy operation. Mechanistic studies suggest that this transformation proceeds via intermolecular condensation of o-aminobenzamides with 2-iodoisothiocyanates, followed by an intramolecular Ullmann-type cross-coupling cyclization reaction.

7.
J Org Chem ; 89(7): 4579-4594, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38506748

RESUMO

A palladium-catalyzed intermolecular [2 + 2 + 2] oxidative coupling-annulation of terminal alkenes and alkynes using copper(II) as the oxidant has been developed through direct C-C bond formation. These reactions provide effective access to multiaryl-substituted benzenes with high regioselectivity in the absence of any ligands. The features of this protocol are broad substrate scope, and high atom and step economy. The aggregation-induced emission properties of selected products were further investigated. These synthesized multiaryl-substituted benzenes may be worth exploring for further applications in the fields of advanced functional materials or drugs.

8.
Fish Shellfish Immunol ; 146: 109425, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316348

RESUMO

As a series of our previous studies reported, recombinant yeast can be the oral vaccines to deliver designed protein and DNA, as well as functional shRNA, into dendritic cells (DCs) in mice for specific immune regulation. Here, we report the further optimization of oral yeast-based vaccine from two aspects (yeast characteristics and recombinant DNA constitution) to improve the effect of immune regulation. After screening four genes in negative regulation of glucan synthesis in yeast (MNN9, GUP1, PBS2 and EXG1), this research combined HDR-based genome editing technology with Cre-loxP technology to acquire 15 gene-knockout strains without drug resistance-gene to exclude biosafety risks; afterward, oral feeding experiments were performed on the mice using 15 oral recombinant yeast-based vaccines constructed by the gene-knockout strains harboring pCMV-MSTN plasmid to screen the target strain with more effective inducing mstn-specific antibody which in turn increasing weight gain effect. And subsequently based on the selected gene-knockout strain, the recombinant DNA in the oral recombinant yeast-based vaccine is optimized via a combination of protein fusion expression (OVA-MSTN) and interfering RNA technology (shRNA-IL21), comparison in terms of both weight gain effect and antibody titer revealed that the selected gene-knockout strain (GUP1ΔEXG1Δ) combined with specific recombinant DNA (pCMV-OVA-MSTN-shIL2) had a better effect of the vaccine. This study provides a useful reference to the subsequent construction of a more efficient oral recombinant yeast-based vaccine in the food and pharmaceutical industry.


Assuntos
DNA Recombinante , Saccharomyces cerevisiae , Camundongos , Animais , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , DNA Recombinante/metabolismo , Vacinas Sintéticas , RNA Interferente Pequeno , Aumento de Peso
9.
BMC Public Health ; 24(1): 1657, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907192

RESUMO

BACKGROUND: With the conflict between the promise of ageing in health and longevity and the limited availability of health resources and social support, older adults in China inevitably experience anxieties surrounding health risks. This study aims to investigate how older adults perceive the health risks that come with getting older, explore the degree to which health risks affect older adults, and advocate for active engagement in practices for managing health risks. METHODS: Using purposive sampling, three districts of Beijing (Xicheng District, Fengtai District, and Daxing District, respectively) were selected for the research. Qualitative semi-structured and in-depth interviews were conducted with 70 community-dwelling older adults who participated in the study. Data were extracted and analyzed based on a thematic framework approach. RESULTS: Three main themes were identified: (i) the anxieties of older adults concerning health risks in ageing; (ii) the priorities of older adults for health risk management in ageing; (iii) the expectations of older adults for health risk management in ageing. The primary health concerns among older adults included disease incidence and function decline. It was found that basic health management emerged as a critical need for older adults to mitigate health risks. Moreover, it was observed that healthcare support for older adults from familial, institutional, and governmental levels exhibited varying degrees of inadequacy. CONCLUSIONS: The primary source of anxieties among older adults regarding health risks predominantly stems from a perceived sense of health deprivation. It is often compounded by persistent barriers to primary care of priorities in managing health risks among older adults. In addition, the expectations of older adults for health risk management emphasize the necessity for integrated care approaches. Therefore, further research should give priority to the prevention and management of health risks, aim to reduce anxieties, provide integrated care to meet the primary needs and expectations of older adults, and ultimately strive toward the overarching goal of promoting health and longevity.


Assuntos
Ansiedade , Vida Independente , Pesquisa Qualitativa , Humanos , Idoso , Feminino , Masculino , Vida Independente/psicologia , Idoso de 80 Anos ou mais , Ansiedade/psicologia , Ansiedade/epidemiologia , Pessoa de Meia-Idade , Envelhecimento/psicologia , Entrevistas como Assunto , China/epidemiologia , Medição de Risco , Prioridades em Saúde
10.
Artigo em Inglês | MEDLINE | ID: mdl-39005076

RESUMO

BACKGROUND: Person-centered primary care measures (PCPCM) facilitate high-quality and culturally appropriate primary care. Access to PCPCM remains unequal between rural and urban areas, and the available evidence on rural PCPCM is still lacking. METHODS: A cross-sectional survey was conducted with stratified sampling by regions, and four districts (Xicheng, Fengtai, Huairou, and Daxing) in Beijing were selected to test the performance of PCPCM in both urban and rural areas. Descriptive statistical methods were used to compare the urban-rural differences in the demographic characteristics of PCPCM. Correlation and regression analyses were performed to determine the associations between PCPCM in demographics and utilization of primary care. RESULTS: The PCPCM showed good reliability and validity in both urban and rural areas (P< 0.001), slightly lower in rural areas, but scores of rural PCPCM (R-PCPCM) in all items were lower than urban PCPCM (U-PCPCM). The PCPCM score for preferring CHCs (U-PCPCM=3.31) or RHCs (R-PCPCM=3.10) was the highest. Patients in urban areas were more likely to receive higher-quality primary care than in rural areas (P < 0.001). Patients who preferred hospitals (ß=2.61, p<0.001) or CHCs (ß=0.71, p=0.003) as providers was a significant positive predictor of U-PCPCM, but it was the preference for hospitals (ß=2.95, p<0.001) for R-PCPCM. CONCLUSIONS: Urban-rural differences existed in the performance of PCPCM, with rural areas typically more difficult to access better PCPCM. To promote health equity in rural areas, healthcare providers should strive to minimize urban-rural differences in the quality and utilization of primary care services as much as feasible.

11.
J Craniofac Surg ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771212

RESUMO

Epidural fluid collection is commonly seen as a low-density accumulation beneath the dura on postoperative computed tomography scans. It is discussed less in the literature because, in most cases, the fluid amount is small, self-absorbing, and typically does not cause neurological deficits, so intervention is usually unnecessary. However, when a significant amount of fluid accumulates, patients may experience symptoms such as altered consciousness and even coma. In such cases, treatment is necessary to reduce intracranial pressure, preventing further deterioration of consciousness and potentially life-threatening situations. The authors report a case of a large epidural fluid collection following cranioplasty, resulting in progressive deterioration of consciousness in the patient. Computed tomography scans indicated brain herniation. Subsequently, percutaneous puncture and suction treatment were performed, followed by appropriate pressure dressing. The patient gradually recovered from a shallow coma to clear consciousness and was discharged after rehabilitation.

12.
Int Wound J ; 21(1): e14649, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38272796

RESUMO

Facial soft tissue injuries, often resulting in scarring, pose a challenge in reconstructive and aesthetic surgery due to the need for functional and aesthetic restoration. This study evaluates the efficacy of recombinant human growth factors (rhGFs) in scar remodelling for such injuries. A retrospective evaluation was conducted from January 2020 to January 2023, involving 100 patients with facial soft tissue injuries. Participants were divided equally into a control group, receiving standard cosmetic surgical repair, and an observation group, treated with rhGFs supplemented cosmetic surgery. The study assessed scar characteristics (pigmentation, pliability, vascularity, height), hospital stay duration, tissue healing time, complication rates and patient satisfaction. The observation group demonstrated significant improvements in all scar characteristics, with notably better pigmentation, pliability, vascularity and height compared with the control group. The rhGF treatment also resulted in reduced hospital stay duration and faster tissue healing. Notably, the total complication rate was significantly lower in the observation group (10%) compared with the control group (34%). Additionally, patient satisfaction levels were higher in the observation group, with 98% combined satisfaction compared with 76% in the control group. The application of rhGFs in treating facial soft tissue injuries significantly enhances scar remodelling, expedites healing, reduces complications and improves patient satisfaction. These findings establish rhGFs as a valuable tool in the management of facial soft tissue injuries, highlighting their potential in improving both functional and aesthetic outcomes.


Assuntos
Traumatismos Faciais , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Humanos , Cicatriz/tratamento farmacológico , Cicatriz/cirurgia , Estudos Retrospectivos , Cicatrização , Lesões dos Tecidos Moles/tratamento farmacológico , Lesões dos Tecidos Moles/cirurgia , Traumatismos Faciais/tratamento farmacológico , Traumatismos Faciais/cirurgia , Resultado do Tratamento
13.
Zhongguo Zhong Yao Za Zhi ; 49(7): 1888-1895, 2024 Apr.
Artigo em Zh | MEDLINE | ID: mdl-38812201

RESUMO

This study observed the effects of Notoginseng Radix et Rhizoma on the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(Akt)/mammalian target of rapamycin complex 1(mTORC1) signaling pathway and mitochondrial energy metabolism in the rat model of adriamycin-induced renal fibrosis with blood stasis syndrome to explore the mechanism of Notoginseng Radix et Rhizoma in protecting the kidney. Thirty male rats with adriamycin-induced renal fibrosis were randomized into model, low-, medium-, and high-dose Notoginseng Radix et Rhizoma, and positive control groups(n=6). Six clean SD male rats were selected into the normal group. The normal group and model group were administrated with normal saline, and other groups with corresponding drugs. After 8 weeks of treatment, the renal function, renal pathology, adenosine triphosphate(ATP) levels, Na~+-K~+-ATPase and Ca~(2+)-Mg~(2+)-ATPase activities, and the protein levels of ATP5B, mTORC1, 70 kDa ribosomal protein S6 kinase(P70S6K), P85, Akt, p-Akt, and SH2-containing inositol phosphatase(SHIP2) in the renal tissue were determined. Compared with the normal group, the model group showed elevated levels of blood urea nitrogen(BUN) and serum creatinine(SCr)(P<0.01). Compared with the model group, Notoginseng Radix et Rhizoma and the positive control lowered the levels of BUN and SCr, which were significant in the medium-and high-dose Noto-ginseng Radix et Rhizoma groups and the positive control group(P<0.05). Compared with the model group, Notoginseng Radix et Rhizoma and the positive control alleviated the pathological changes in the renal tissue, such as vacuolar and fibroid changes, glomerulus atrophy, cystic expansion of renal tubules, and massive infiltration of inflammatory cells. Compared with the normal group, the model group showed decreased mitochondrial ATP content and Na~+-K~+-ATPase and Ca~(2+)-Mg~(2+)-ATPase activities in the renal tissue(P<0.05), and medium-and high-dose Notoginseng Radix et Rhizoma and positive control mitigated such decreases(P<0.05). Compared with the model group, medium-and high-dose Notoginseng Radix et Rhizoma and the positive control up-regulated the protein levels of ATP5B and SHIP2 and down-regulated the protein levels of mTORC1, P70S6K, P85, Akt, and p-Akt(P<0.05 or P<0.01 or P<0.001). Notoginseng Radix et Rhizoma may exert an anti-fibrosis effect by inhibiting the activation of the PI3K/Akt/mTORC1 pathway to restore mitochondrial energy metabolism, thus protecting the kidney.


Assuntos
Medicamentos de Ervas Chinesas , Metabolismo Energético , Alvo Mecanístico do Complexo 1 de Rapamicina , Mitocôndrias , Panax notoginseng , Proteínas Proto-Oncogênicas c-akt , Ratos Sprague-Dawley , Animais , Masculino , Ratos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Panax notoginseng/química , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Metabolismo Energético/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/administração & dosagem , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/genética , Rizoma/química , Humanos , Transdução de Sinais/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/metabolismo , Insuficiência Renal/tratamento farmacológico , Insuficiência Renal/metabolismo
14.
J Biol Chem ; 298(7): 102103, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35671823

RESUMO

Base editing has emerged as a revolutionary technology for single nucleotide modifications. The cytosine and adenine base editors (CBEs and ABEs) have demonstrated great potential in clinical and fundamental research. However, screening and isolating target-edited cells remains challenging. In the current study, we developed a universal Adenine and Cytosine Base-Editing Antibiotic Resistance Screening Reporter (ACBE-ARSR) for improving the editing efficiency. To develop the reporter, the CBE-ARSR was first constructed and shown to be capable of enriching cells for those that had undergone CBE editing activity. Then, the ACBE-ARSR was constructed and was further validated in the editing assays by four different CBEs and two versions of ABE at several different genomic loci. Our results demonstrated that ACBE-ARSR, compared to the reporter of transfection (RoT) screening strategy, improved the editing efficiency of CBE and ABE by 4.6- and 1.9-fold on average, respectively. We found the highest CBE and ABE editing efficiencies as enriched by ACBE-ARSR reached 90% and 88.7%. Moreover, we also demonstrated ACBE-ARSR could be employed for enhancing simultaneous multiplexed genome editing. In conclusion, both CBE and ABE activity can be improved significantly using our novel ACBE-ARSR screening strategy, which we believe will facilitate the development of base editors and their application in biomedical and fundamental research studies.


Assuntos
Adenina , Citosina , Resistência Microbiana a Medicamentos , Edição de Genes , Testes de Sensibilidade Microbiana , Adenina/química , Citosina/química , Edição de Genes/métodos , Testes de Sensibilidade Microbiana/métodos
15.
J Biol Chem ; 298(3): 101702, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35148990

RESUMO

GlcNAc-1-phosphotransferase catalyzes the initial step in the formation of the mannose-6-phosphate tag that labels ∼60 lysosomal proteins for transport. Mutations in GlcNAc-1-phosphotransferase are known to cause lysosomal storage disorders such as mucolipidoses. However, the molecular mechanism of GlcNAc-1-phosphotransferase activity remains unclear. Mammalian GlcNAc-1-phosphotransferases are α2ß2γ2 hexamers in which the core catalytic α- and ß-subunits are derived from the GNPTAB (N-acetylglucosamine-1-phosphate transferase subunits alpha and beta) gene. Here, we present the cryo-electron microscopy structure of the Drosophila melanogaster GNPTAB homolog, DmGNPTAB. We identified four conserved regions located far apart in the sequence that fold into the catalytic domain, which exhibits structural similarity to that of the UDP-glucose glycoprotein glucosyltransferase. Comparison with UDP-glucose glycoprotein glucosyltransferase also revealed a putative donor substrate-binding site, and the functional requirements of critical residues in human GNPTAB were validated using GNPTAB-knockout cells. Finally, we show that DmGNPTAB forms a homodimer that is evolutionarily conserved and that perturbing the dimer interface undermines the maturation and activity of human GNPTAB. These results provide important insights into GlcNAc-1-phosphotransferase function and related diseases.


Assuntos
Lisossomos , Mucolipidoses , Transferases (Outros Grupos de Fosfato Substituídos) , Animais , Microscopia Crioeletrônica , Drosophila melanogaster , Lisossomos/química , Lisossomos/genética , Lisossomos/metabolismo , Mamíferos/metabolismo , Mucolipidoses/genética , Proteínas , Relação Estrutura-Atividade , Transferases (Outros Grupos de Fosfato Substituídos)/química , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo
16.
Biochem Biophys Res Commun ; 643: 48-54, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36586158

RESUMO

Gastric cancer is highly malignant and recalcitrant to first line chemotherapies that include 5-fluorouracil (5-FU). Cancer cells are addicted to methionine for their proliferation and survival. Methionine addiction of cancer is known as the Hoffman effect. Methionine restriction with recombinant methioninase (rMETase) has been shown to selectively starve cancer cells and has shown synergy with cytotoxic chemotherapy including 5-FU. The present study aimed to investigate the efficacy of rMETase alone and the combination with 5-FU on poorly differentiated human gastric cancer cell lines (MKN45, NUGC3, and NUGC4) in vitro and vivo. rMETase suppressed the tumor growth of 3 kinds of poorly differentiated gastric cancer cells in vitro. The fluorescence ubiquitination-based cell cycle indicator (FUCCI) demonstrated cancer cells treated with rMETase were selectively trapped in the S/G2 phase of the cell cycle. In the present study, subcutaneous MKN45 gastric cancer models were randomized into four groups when the tumor volume reached 100 mm3: G1: untreated control; G2: 5-FU (i.p., 50 mg/kg, weekly, three weeks); G3: oral-rMETase (o-rMETase) (p.o., 100 units/body, daily, three weeks); G4: 5-FU with o-rMETase (5-FU; i.p., 50 mg/kg, weekly, three weeks o-rMETase; p.o., 100 units/body, daily, three weeks). All mice were sacrificed on day 22. Body weight and estimated tumor volume were measured twice a week. 5-FU and o-rMETase suppressed tumor growth as monotherapies on day 18 (p = 0.044 and p = 0.044). However, 5-FU combined with o-rMETase was significantly superior to each monotherapy (p < 0.001 and p < 0.001, respectively) and induced extensive necrosis compared to other groups. The combination of 5-FU and o-rMETase shows promise for transformative therapy for poorly differentiated gastric cancer in the clinic.


Assuntos
Fluoruracila , Neoplasias Gástricas , Camundongos , Humanos , Animais , Fluoruracila/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Liases de Carbono-Enxofre , Metionina/metabolismo , Proteínas Recombinantes/farmacologia
17.
Small ; 19(39): e2300890, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37246273

RESUMO

Sliding-freestanding triboelectric nanogenerators (SF-TENGs) are desirable for application in wearable power sources; however, improving their durability is the primary challenge. Meanwhile, few studies focus on enhancing the service life of tribo-materials, especially from an anti-friction perspective during dry operation. Herein, for the first time, a surface-textured film with self-lubricating property is introduced into the SF-TENG as a tribo-material, which is obtained by the self-assembly of hollow SiO2 microspheres (HSMs) close to a polydimethylsiloxane (PDMS) surface under vacuum conditions. The PDMS/HSMs film with micro-bump topography simultaneously reduces the dynamic coefficient of friction from 1.403 to 0.195 and increases the electrical output of SF-TENG by an order of magnitude. Subsequently, a textured film and self-adapting contact synergized bidirectional rotary TENG (TAB-TENG) is developed, and the superiorities of the soft flat rotator with bidirectional reciprocating rotation are systematically investigated. The obtained TAB-TENG exhibits a remarkable output stability and an outstanding mechanical durability over 350 000 cycles. Furthermore, a smart foot system for stepping energy harvesting and wireless walking states monitoring is realized. This study proposes a pioneering strategy for extending the lifetime of SF-TENGs and advances it toward practical wearable applications.

18.
Purinergic Signal ; 19(1): 43-53, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35389158

RESUMO

This study explored the role of P2X7 receptors in spinal cord astrocytes in the electroacupuncture-induced inhibition of visceral hypersensitivity (VH) in rats with irritable bowel syndrome (IBS). Visceral hypersensitivity of IBS was intracolonically induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). Visceromotor responses to colorectal distension (CRD-20,40,60,80 mmHg) and abdominal withdrawal reflex scoring (AWRs) were recorded after electroacupuncture at bilateral Zusanli (ST36) and Sanyinjiao (SP6) acupoints to evaluate the analgesic effect of electroacupuncture on visceral pain in rats with IBS. Fluorocitric acid (FCA), an astrocyte activity inhibitor, was injected intrathecally before electroacupuncture intervention and AWRs were recorded. Western blot and real-time qPCR were used to detect the expression of NMDA and P2X7 receptor to observe the regulation effect of electroacupuncture on NMDA receptor in the spinal cord of rats with visceral hypersensitivity. Intrathecal injection of P2X7 agonist or antagonist was administered before electroacupuncture treatment. To observe the effect of P2X7 receptor in spinal astrocytes on the inhibition of visceral hyperalgesia by electroacupuncture, the changes of AWR score, NMDA receptor in the spinal cord, and GFAP expression in astrocytes were detected. Inflammation of the colon had basically subsided at day 21 post-TNBS; persistent visceral hypersensitivity could be suppressed by electroacupuncture. This analgesic effect could be inhibited by FCA. The analgesic effect, downregulation of NMDA receptor NR1 subunit, and P2X7 protein of electroacupuncture were all reversed by FCA. P2X7 receptor antagonist A740003 can cooperate with EA to carry out analgesic effect in rats with visceral pain and downregulate the expression of NR1, NR2B, and GFAP in spinal dorsal horn. However, the P2X7 receptor agonist BzATP could partially reverse the analgesic effect of EA, inhibiting the downregulatory effect of EA on the expression of NR1, NR2B, and GFAP. These results indicate that EA may downregulate the expression of the NMDA receptor by inhibiting the P2X7 receptor in the spinal cord, thereby inhibiting spinal cord sensitization in IBS rats with visceral pain, in which astrocytes are an important medium.


Assuntos
Eletroacupuntura , Hipersensibilidade , Síndrome do Intestino Irritável , Dor Visceral , Ratos , Animais , Síndrome do Intestino Irritável/metabolismo , Síndrome do Intestino Irritável/terapia , Ratos Sprague-Dawley , Astrócitos/metabolismo , Dor Visceral/metabolismo , Eletroacupuntura/métodos , Receptores de N-Metil-D-Aspartato/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Medula Espinal/metabolismo , Corno Dorsal da Medula Espinal/metabolismo , Hipersensibilidade/metabolismo , Analgésicos
19.
Sleep Breath ; 27(4): 1495-1504, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36205809

RESUMO

PURPOSE: Sleep disturbances exacerbate the progression of Alzheimer's disease (AD), but disturbances of non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep may have different effects. Neurofilament light chain (NfL), an axon-specific protein, is an indicator of the severity of neuronal apoptosis. To investigate whether or not NREM or REM sleep is crucial to neuronal survival, we examined the effects of induced NREM or REM sleep loss on NfL levels in APP/PS1 mice, a model of AD, and their wild-type (WT) C57BL/6 J littermates. METHODS: At 6 months of age, WT mice and AD mice were equally divided into six groups, namely, the WT-normal sleep (S), WT-total sleep deprivation (TSD), WT-REM deprivation (RD), AD-S, AD-TSD and AD-RD groups, according to the type of sleep intervention applied. All mice underwent 6 days of sleep intervention. Cerebrospinal fluid (CSF) and plasma NfL levels were measured at baseline and on days 2, 4 and 6, and spatial memory was assessed in the Morris water maze (MWM) test. RESULTS: Among the 18 WT and 18 AD mice, CSF and plasma NfL levels were higher in AD-TSD mice than in AD-S or AD-RD mice, while no significant difference was observed between the latter two groups. In AD-TSD mice, CSF and plasma NfL levels increased with the duration of sleep deprivation. A similar pattern of results was observed for the WT groups. CONCLUSIONS: NREM sleep loss may increase CSF and plasma NfL levels in both WT and AD mice.


Assuntos
Doença de Alzheimer , Privação do Sono , Camundongos , Animais , Filamentos Intermediários , Camundongos Endogâmicos C57BL , Sono/fisiologia
20.
Nano Lett ; 22(23): 9723-9731, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36459114

RESUMO

Strontium-containing agents have been demonstrated to elicit both bone anabolic and antiosteoporotic effects, showing great potential for the treatment of bone loss. However, an increased incidence of strontium-induced side effects restricts their clinical applications. Herein, oxidized carbon nitride nanosheets (CN) are delicately used to incorporate Sr2+ for the first time to achieve high osteogenic efficacy. The lamellar structure and enriched nitrogen species of CN provide them with a high surface area-to-volume ratio and abundant anchoring sites for Sr2+ incorporation. Importantly, Sr2+-incorporated CN (CNS) could synergistically promote osteoblast differentiation and bone regeneration at a single, very low Sr2+ dose. Mechanically, CNS could activate the FAK/RhoA signaling pathway to modulate the intracellular tension that stimulates osteoblasts differentiation. The present study will provide a new paradigm to enhance the efficacy of osteogenic metal ions by using lamellar nanocarriers.


Assuntos
Regeneração Óssea , Estrôncio , Estrôncio/farmacologia , Osteogênese , Osso e Ossos
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