Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 339
Filter
1.
Acta Pharm Sin B ; 14(9): 4028-4044, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39309487

ABSTRACT

There are only eight approved small molecule antiviral drugs for treating COVID-19. Among them, four are nucleotide analogues (remdesivir, JT001, molnupiravir, and azvudine), while the other four are protease inhibitors (nirmatrelvir, ensitrelvir, leritrelvir, and simnotrelvir-ritonavir). Antiviral resistance, unfavourable drug‒drug interaction, and toxicity have been reported in previous studies. Thus there is a dearth of new treatment options for SARS-CoV-2. In this work, a three-tier cell-based screening was employed to identify novel compounds with anti-SARS-CoV-2 activity. One compound, designated 172, demonstrated broad-spectrum antiviral activity against multiple human pathogenic coronaviruses and different SARS-CoV-2 variants of concern. Mechanistic studies validated by reverse genetics showed that compound 172 inhibits the 3-chymotrypsin-like protease (3CLpro) by binding to an allosteric site and reduces 3CLpro dimerization. A drug synergistic checkerboard assay demonstrated that compound 172 can achieve drug synergy with nirmatrelvir in vitro. In vivo studies confirmed the antiviral activity of compound 172 in both Golden Syrian Hamsters and K18 humanized ACE2 mice. Overall, this study identified an alternative druggable site on the SARS-CoV-2 3CLpro, proposed a potential combination therapy with nirmatrelvir to reduce the risk of antiviral resistance and shed light on the development of allosteric protease inhibitors for treating a range of coronavirus diseases.

2.
Acta Pharm Sin B ; 14(9): 4164-4173, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39309499

ABSTRACT

Viruses often manipulate ubiquitination pathways to facilitate their replication and pathogenesis. CUL2ZYG11B known as the substrate receptor of cullin-2 RING E3 ligase, is bound by SARS-CoV-2 ORF10 to increase its E3 ligase activity, leading to degradation of IFT46, a protein component of the intraflagellar transport (IFT) complex B. This results in dysfunctional cilia, which explains certain symptoms that are specific to COVID-19. However, the precise molecular mechanism of how ORF10 recognizes CUL2ZYG11B remains unknown. Here, we determined the crystal structure of CUL2ZYG11B complexed with the N-terminal extension (NTE) of SARS-CoV-2 ORF10 (2.9 Å). The structure reveals that the ORF10 N-terminal heptapeptide (NTH) mimics the Gly/N-degron to bind CUL2ZYG11B. Mutagenesis studies identified key residues within ORF10 that are key players in its interaction with CUL2ZYG11B both in ITC assay and in vivo cells. In addition, we prove that enhancement of CUL2ZYG11B activity for IFT46 degradation by which ORF10-mediated correlates with the binding affinity between ORF10 and CUL2ZYG11B. Finally, we used a Global Protein Stability system to show that the NTH of ORF10 mimics the Gly/N-degron motif, thereby binding competitively to CUL2ZYG11B and inhibiting the degradation of target substrates bearing the Gly/N-degron motif. Overall, this study sheds light on how SARS-CoV-2 ORF10 exploits the ubiquitination machinery for proteasomal degradation, and offers valuable insights for optimizing PROTAC-based drug design based on NTH CUL2ZYG11B interaction, while pinpointing a promising target for the development of treatments for COVID-19.

3.
Inorg Chem ; 63(38): 17608-17616, 2024 Sep 23.
Article in English | MEDLINE | ID: mdl-39250526

ABSTRACT

Exploring the relationship between semiconductor structure and surface-enhanced Raman scattering (SERS) activity was essential for the development of ultrasensitive SERS substrates. Herein, we report an ytterbium atomic doping strategy to render TiO2 (Yb-TiO2) highly SERS sensitive superior to pure TiO2, with a detection limit as low as 1 × 10-9 M for 4-mercaptobenzoic acid. First-principles density functional theory calculations reveal that ytterbium doping leads to high electrostatic properties, allowing for significant charge transfer from molecules to semiconductors. Theoretical and experimental results indicate that Yb-TiO2 has a smaller band gap and higher density of states, which effectively enhance charge transfer between molecules and substrates, resulting in significant SERS activity. More importantly, Yb-TiO2 was particularly stable in air and acid solution and can be used for trace molecule detection in extreme environments. We demonstrate a promising approach to construct ultrasensitive SERS by optimizing the electronic structure induced by geometric structures.

4.
Atherosclerosis ; 397: 118549, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39141976

ABSTRACT

BACKGROUND AND AIMS: The objective of this study was to investigate the efficacy of CRISPR/Cas9-mediated A4GALT suppression in rescuing endothelial dysfunction in Fabry disease (FD) endothelial cells (FD-ECs) derived from human induced pluripotent stem cells (hiPSCs). METHODS: We differentiated hiPSCs (WT (wild-type), WTC-11), GLA-mutant hiPSCs (GLA-KO, CMC-Fb-002), and CRISPR/Cas9-mediated A4GALT-KO hiPSCs (GLA/A4GALT-KO, Fb-002-A4GALT-KO) into ECs and compared FD phenotypes and endothelial dysfunction. We also analyzed the effect of A4GALT suppression on reactive oxygen species (ROS) formation and transcriptome profiles through RNA sequencing. RESULTS: GLA-mutant hiPSC-ECs (GLA-KO and CMC-Fb-002) showed downregulated expression of EC markers and significantly reduced α-GalA expression with increased Gb-3 deposition and intra-lysosomal inclusion bodies. However, CRISPR/Cas9-mediated A4GALT suppression in GLA/A4GALT-KO and Fb-002-A4GALT-KO hiPSC-ECs increased expression levels of EC markers and rescued these FD phenotypes. GLA-mutant hiPSC-ECs failed to form tube-like structure in tube formation assays, showing significantly decreased migration of cells into the scratched wound area. In contrast, A4GALT suppression improved tube formation and cell migration capacity. Western blot analysis revealed that MAPK and AKT phosphorylation levels were downregulated while SOD and catalase were upregulated in GLA-KO hiPSC-ECs. However, suppression of A4GALT restored these protein alterations. RNA sequencing analysis demonstrated significant transcriptome changes in GLA-mutant EC, especially in angiogenesis, cell death, and cellular response to oxidative stress. However, these were effectively restored in GLA/A4GALT-KO hiPSC-ECs. CONCLUSIONS: CRISPR/Cas9-mediated A4GALT suppression rescued FD phenotype and endothelial dysfunction in GLA-mutant hiPSC-ECs, presenting a potential therapeutic approach for FD-vasculopathy.


Subject(s)
CRISPR-Cas Systems , Cell Differentiation , Endothelial Cells , Fabry Disease , Galactosyltransferases , Induced Pluripotent Stem Cells , Reactive Oxygen Species , alpha-Galactosidase , Humans , Induced Pluripotent Stem Cells/metabolism , Fabry Disease/metabolism , Fabry Disease/genetics , Endothelial Cells/metabolism , alpha-Galactosidase/genetics , alpha-Galactosidase/metabolism , Galactosyltransferases/genetics , Galactosyltransferases/metabolism , Reactive Oxygen Species/metabolism , Phenotype , Mutation , Trihexosylceramides/metabolism , Cells, Cultured , Transcriptome , Signal Transduction , Cell Line , Oxidative Stress
5.
Stem Cell Res ; 81: 103522, 2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39163808

ABSTRACT

Gitelman's disease is caused by a genetic mutation in the solute carrier family 12 member 3 (SLC12A3) gene, which encodes the sodium chloride cotransporter. In this study, we generated a stable human induced pluripotent stem cell (hiPSC) line, WTC11-SLC12A3 (CMCi014-A-82), by knocking in the entire SLC12A3 gene at the SHS231 locus in healthy wild-type control hiPSCs (WTC11). We verified that WTC11-SLC12A3 expressed pluripotency markers and exhibited normal stem cell morphology. Furthermore, this cell line maintains a normal karyotype and can differentiate into the three germ layers. Therefore, this cell line may provide a basis for gene therapy for Gitelman's disease.

7.
Stem Cell Res ; 80: 103499, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39111000

ABSTRACT

We generated a human induced pluripotent stem cell (hiPSC) line (CMCi014-A-78) expressing a GFP reporter in the 3'-UTR region of the KLOTHO locus using CRISPR/Cas9-mediated homologous recombination to screen for candidates regulating KLOTHO. The established cell line exhibits a normal karyotype, typical stem cell morphology, expression of pluripotency markers, and the ability to differentiate into the three germ layers. Consequently, this hiPSC line could serve as a valuable resource for screening KLOTHO regulators in hiPSC-derived target cells or organoids.


Subject(s)
3' Untranslated Regions , Glucuronidase , Green Fluorescent Proteins , Induced Pluripotent Stem Cells , Klotho Proteins , Humans , Induced Pluripotent Stem Cells/metabolism , Induced Pluripotent Stem Cells/cytology , Green Fluorescent Proteins/metabolism , Green Fluorescent Proteins/genetics , Glucuronidase/metabolism , Glucuronidase/genetics , Cell Line , CRISPR-Cas Systems , Genes, Reporter , Cell Differentiation , Gene Knock-In Techniques/methods , Genetic Loci
8.
BMC Biol ; 22(1): 176, 2024 Aug 26.
Article in English | MEDLINE | ID: mdl-39183304

ABSTRACT

BACKGROUND: Casein kinase 1α (CK1α), expressed in both ovarian germ and somatic cells, is involved in the initial meiosis and primordial follicle formation of mouse oocytes. Using in vitro and in vivo experiments in this study, we explored the function and mechanism of CK1α in estrogen synthesis in mice ovarian granulosa cells. METHODS: A CK1α knockout (cKO) mouse model, targeted specifically to ovarian granulosa cells (GCs), was employed to establish the influence of CK1α on in vivo estrogen synthesis. The influence of CK1α deficiency on GCs was determined in vivo and in vitro by immunofluorescence analysis and Western blot assay. Transcriptome profiling, differentially expressed genes and gene functional enrichment analyses, and computation protein-protein docking, were further employed to assess the CK1α pathway. Furthermore, wild-type female mice were treated with the CK1α antagonist D4476 to elucidate the CK1α's role in estrogen regulation. RESULTS: Ovarian GCs CK1α deficiency impaired fertility and superovulation of female mice; also, the average litter size and the estradiol (E2) level in the serum of cKO female mice were decreased by 57.3% and 87.4% vs. control mice, respectively. This deficiency disrupted the estrous cycle and enhanced the apoptosis in the GCs. We observed that CK1α mediated the secretion of estradiol in mouse ovarian GCs via the cytochrome P450 subfamily 19 member 1 (CYP19A1). CONCLUSIONS: These findings improve the existing understanding of the regulation mechanism of female reproduction and estrogen synthesis. TRIAL REGISTRATION: Not applicable.


Subject(s)
Aromatase , Estradiol , Granulosa Cells , Mice, Knockout , Animals , Female , Mice , Aromatase/metabolism , Aromatase/genetics , Casein Kinase Ialpha/metabolism , Casein Kinase Ialpha/genetics , Estradiol/metabolism , Granulosa Cells/metabolism
9.
Animals (Basel) ; 14(14)2024 Jul 12.
Article in English | MEDLINE | ID: mdl-39061513

ABSTRACT

As a transcription factor, Nuclear Receptor Subfamily 4 Group A Member 1 (NR4A1) binds to downstream target genes to participate in cell proliferation and cell differentiation. We found that the NR4A1 reached the highest expression at 60 h after the differentiation of goat intramuscular preadipocytes. Overexpression of goat NR4A1 increased the number of intracellular lipid droplets and up-regulated the expression of adipocyte-differentiation-related marker genes including AP2, SREBP1, ACC, GPAM, and DGAT2, while the relative expression levels of Pref-1 and HSL were significantly decreased. On the contrary, after NR4A1 was knocked down by siRNA, the number of intracellular lipid droplets and the relative expression levels of LPL, CEBPα, CEBPß, ACC, and DGAT2 were significantly decreased, and the relative expression levels of Pref-1 and HSL were significantly up-regulated. These results suggest that NR4A1 promotes the differentiation of goat intramuscular preadipocytes. Transcriptome sequencing was carried out after overexpression of goat NR4A1, and the KEGG enrichment analysis result showed that the most differentially expressed genes were related to adipocyte differentiation and were enriched in the PI3K-Akt signaling pathway. LY249002, an inhibitor of the PI3K-Akt signaling pathway, was introduced and decreased the number of intracellular lipid droplets, and the relative expression levels of C/EBPα, SREBP1, AP2, C/EBPß, GPAM, ACC, DGAT1, DGAT2, and ATGL were decreased accordingly. The above results indicate that overexpression of goat NR4A1 may promote the differentiation of intramuscular preadipocytes through the PI3K-Akt signaling pathway.

10.
J Colloid Interface Sci ; 677(Pt A): 11-24, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39079212

ABSTRACT

The persistent release of tetracycline into the environment significantly endangers both ecosystems and human health. Zinc indium sulfide (ZnIn2S4) capable to degrade tetracycline pollutants under visible light irradiation has attracted extensive attentions and great effort has been devoted to augment its catalytic efficacy. In this work, we synthesized a p-n heterojunction, NiFe2O4/ZnIn2S4, to enhance the carrier migration rate and explained the intrinsic mechanism by density functional theory. When the heterojunction was formed, carriers traversed from the n-type NiFe2O4 to the p-type ZnIn2S4, instigating the emergence of a built-in electric field to facilitate the separation of carriers. 2 %-NiFe2O4/ZnIn2S4 exhibited excellent photocatalytic efficiency in tetracycline (TC) degradation and total organic carbon (TOC) removal. Compared to pure ZnIn2S4 and NiFe2O4, the TC degradation rates of 2 %-NiFe2O4/ZnIn2S4 were 2.0 times and 16.9 times higher, respectively. Additionally, 2 %-NiFe2O4/ZnIn2S4 had a saturation magnetization intensity of 3.05 emu/g, allowing for rapid recovery of the catalyst under a magnetic field. Superoxide radicals (O2-) and holes (h+) were the primary active species driving the degradation process. Furthermore, potential reaction pathways of tetracycline in this photocatalytic process were determined and bioconcentration factor and developmental toxicity of the intermediate products were accessed. This work held great potentials for wastewater treatment and provided a pathway for the development of magnetic recyclable photocatalysts.

11.
Cells ; 13(14)2024 Jul 13.
Article in English | MEDLINE | ID: mdl-39056771

ABSTRACT

Genetic or hereditary kidney disease stands as a pivotal cause of chronic kidney disease (CKD). The proliferation and widespread utilization of DNA testing in clinical settings have notably eased the diagnosis of genetic kidney diseases, which were once elusive but are now increasingly identified in cases previously deemed CKD of unknown etiology. However, despite these diagnostic strides, research into disease pathogenesis and novel drug development faces significant hurdles, chiefly due to the dearth of appropriate animal models and the challenges posed by limited patient cohorts in clinical studies. Conversely, the advent and utilization of human-induced pluripotent stem cells (hiPSCs) offer a promising avenue for genetic kidney disease research. Particularly, the development of hiPSC-derived kidney organoid systems presents a novel platform for investigating various forms of genetic kidney diseases. Moreover, the integration of the CRISPR/Cas9 technique into this system holds immense potential for efficient research on genetic kidney diseases. This review aims to explore the applications of in vitro kidney organoids generated from hiPSCs in the study of diverse genetic kidney diseases. Additionally, it will delve into the limitations of this research platform and outline future perspectives for advancing research in this crucial area.


Subject(s)
Induced Pluripotent Stem Cells , Kidney Diseases , Kidney , Organoids , Humans , Organoids/pathology , Organoids/metabolism , Induced Pluripotent Stem Cells/metabolism , Kidney Diseases/genetics , Kidney Diseases/pathology , Kidney/pathology , Animals , CRISPR-Cas Systems/genetics
12.
Polymers (Basel) ; 16(11)2024 May 24.
Article in English | MEDLINE | ID: mdl-38891444

ABSTRACT

Plasma-initiated polymerization (PIP) is generally attributed to a radical process due to its inhibiting property. However, its unique polymerization behaviors like long-lived radical and solvent effect do not comply well with the traditional radical mechanism. Herein, the PIP of methyl methacrylate (MMA) was conducted in a high-voltage DC electric field to investigate the charged nature of its radicals. Consequently, the polymerization presented a preferential distribution of polymers at the anode but not the cathode, revealing the negatively charged nature of the growing radicals. An acceleration phenomenon, accompanied by the growth in molecular weights and the reduction in molecular weight distributions (Ð), was observed at the voltages above 16 kV, suggesting the dissociation of ion pairs of growing radicals. The PIP yielded PMMA with analogous chemical and steric structures to those of PMMA from traditional radical initiation, whether in the presence or absence of the external electric field. This work offers new insights into the PIP of vinyl monomers, wherein a one-electron transfer reaction is inferred to be involved in the monomer activation.

13.
Gels ; 10(6)2024 May 31.
Article in English | MEDLINE | ID: mdl-38920925

ABSTRACT

Given the increasingly severe environmental problems caused by water pollution, the degradation of organic dyes can be effectively achieved through the utilization of photocatalysis. In this work, metal alkoxides and a combination of alcohol/hydrophobic solvents are employed to prepare BaTiO3 aerogels via a liquid-phase and template-free synthetic route. The preparation process of the aerogels solely entails facile agitation and supercritical drying, eliminating the need for additional heat treatment. The binary solvent of ethanol and toluene is identified as the optimal choice, resulting in a significantly enhanced surface area (up to 223 m2/g) and an abundant pore structure of BaTiO3 aerogels compared to that of the BaTiO3 nanoparticles. Thus, the removal efficiency of the BaTiO3 aerogel sample for MO is nearly twice as high as that of the BaTiO3 nanoparticles sample. Noble metal Ag nanoparticles' deposition onto the BaTiO3 aerogel surface is further achieved via the photochemical deposition method, which enhances the capture of photogenerated electrons, thereby ensuring an elevated level of photocatalytic efficiency. As a result, Ag nanoparticles deposited on BaTiO3 aerogel can degrade MO completely after 40 min of illumination, while the corresponding aerogel before modification can only remove 80% of MO after 60 min. The present work not only complements the preparatory investigation of intricate aerogels but also offers a fresh perspective for the development of diverse perovskite aerogels with broad applications.

14.
Cell Rep ; 43(7): 114391, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-38923459

ABSTRACT

Inhibition of nucleic acid targets is mediated by Argonaute (Ago) proteins guided by RNA or DNA. Although the mechanisms underpinning the functions of eukaryotic and "long" prokaryotic Ago proteins (pAgos) are well understood, those for short pAgos remain enigmatic. Here, we determine two cryoelectron microscopy structures of short pAgos in association with the NADase-domain-containing protein Sir2-APAZ from Geobacter sulfurreducens (GsSir2/Ago): the guide RNA-target DNA-loaded GsSir2/Ago quaternary complex (2.58 Å) and the dimer of the quaternary complex (2.93Å). These structures show that the nucleic acid binding causes profound conformational changes that result in disorder or partial dissociation of the Sir2 domain, suggesting that it adopts a NADase-active conformation. Subsequently, two RNA-/DNA-loaded GsSir2/Ago complexes form a dimer through their MID domains, further enhancing NADase activity through synergistic effects. The findings provide a structural basis for short-pAgo-mediated defense against invading nucleic acids.


Subject(s)
Argonaute Proteins , Argonaute Proteins/metabolism , Argonaute Proteins/chemistry , Geobacter/metabolism , Bacterial Proteins/metabolism , Bacterial Proteins/chemistry , Sirtuin 2/metabolism , Protein Multimerization , Protein Binding , Cryoelectron Microscopy , Enzyme Activation , Models, Molecular , Nucleic Acids/metabolism
15.
J Med Chem ; 67(12): 10211-10232, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38871484

ABSTRACT

Papain-like protease (PLpro) is a promising therapeutic target for its pivotal role in the life cycle of SARS-CoV-2. A series of 1,2,4-oxadiazole derivatives was designed and synthesized via a ring formation strategy based on SARS-CoV-2 PLpro-GRL0617 complex structure. Systematic structure-activity relationship studies revealed that introducing oxadiazole and aryl carboxylic acid moieties to GRL0617 enhanced the enzymatic inhibition activity, affinity, and deubiquitination capacity toward PLpro. 1,2,4-Oxadiazole compounds 13f and 26r, which had PLpro inhibition activity (IC50 = 1.8 and 1.0 µM) and antiviral activity against SARS-CoV-2 (EC50 = 5.4 and 4.3 µM), exhibited good metabolic stability (t1/2 > 93.2 min) and higher plasma exposure (AUC0-t = 17,380.08 and 24,289.76 ng·h/mL) in mice. Especially, compound 26r with moderate oral bioavailability of 39.1% and potent antiviral activity is worthy of further studies in vivo. Our findings provide a new insight for the discovery of antiviral agents targeting PLpro.


Subject(s)
Antiviral Agents , Drug Design , Oxadiazoles , SARS-CoV-2 , Oxadiazoles/chemistry , Oxadiazoles/pharmacology , Oxadiazoles/chemical synthesis , Oxadiazoles/pharmacokinetics , Animals , Antiviral Agents/pharmacology , Antiviral Agents/chemical synthesis , Antiviral Agents/chemistry , Antiviral Agents/pharmacokinetics , Structure-Activity Relationship , SARS-CoV-2/drug effects , Mice , Humans , Carboxylic Acids/chemistry , Carboxylic Acids/pharmacology , Carboxylic Acids/chemical synthesis , Molecular Docking Simulation , Protease Inhibitors/pharmacology , Protease Inhibitors/chemical synthesis , Protease Inhibitors/chemistry , Protease Inhibitors/pharmacokinetics , COVID-19 Drug Treatment , Coronavirus Papain-Like Proteases/antagonists & inhibitors , Coronavirus Papain-Like Proteases/metabolism
16.
Article in English | MEDLINE | ID: mdl-38934039

ABSTRACT

Background: The aim of this study is to investigate the specific pathway involved in human leukocyte antigen (HLA) sensitization using single-cell RNA-sequencing analysis and an allo-sensitized mouse model developed with an HLA.A2 transgenic mouse. Methods: For sensitization, wild-type C57BL/6 mouse received two skin grafts from C57BL/6-Tg(HLA-A2.1)1Enge/J mouse (allogeneic mouse, ALLO). For syngeneic control (SYN), skin grafts were transferred from C57BL/6 to C57BL/6. We performed single-cell RNA-sequencing analysis on splenocytes isolated from ALLO and SYN and compared the gene expression between them. Results: We generated 9,190 and 8,890 single-cell transcriptomes from ALLO and SYN, respectively. Five major cell types (B cells, T cells, natural killer cells, macrophages, and neutrophils) and their transcriptome data were annotated according to the representative differentially expressed genes of each cell cluster. The percentage of B cells was higher in ALLO than it was in SYN. Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the highly expressed genes in the B cells from ALLO were mainly associated with antigen processing and presentation pathways, allograft rejection, and the Th17 cell differentiation pathway. Upregulated genes in the T cells of ALLO were involved in the interleukin (IL)-17 signaling pathway. The ratio of Th17 cluster and Treg cluster was increased in the ALLO. On flow cytometry, the percentage of Th17 (IL-17+/CD4+ T) cells was higher and regulatory T cells (FOXP3+/CD4+ T) was lower in the ALLO compared to those in the SYN. Conclusion: Our results indicate that not only the B cell lineage but also the Th17 cells and their cytokine (IL-17) are involved in the sensitization to HLA.

17.
Gels ; 10(5)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38786208

ABSTRACT

Aerogels, as a new type of high-temperature-resistant insulation material, find extensive application in aerospace, high-temperature industrial furnaces, new energy batteries, and various other domains, yet still face some limitations such as inadequate temperature resistance and pronounced brittleness. In this work, SiC/HfC composite aerogels were prepared through a combination of sol-gel method, atmospheric pressure drying technique, and carbothermal reduction reaction. The effects of different molar ratios, calcination time, and temperatures on the microstructural features and physicochemical properties of the resulting SiC/HfC composite aerogels were investigated. The aerogel exhibited an elevated BET-specific surface area of 279.75 m2/g, while the sample displayed an extraordinarily low thermal conductivity of 0.052 W/(m·K). Most notably, the compressive strength reached an outstanding 5.93 MPa after a carbonization temperature of 1500 °C, far exceeding the values reported in prior aerogel studies. This research provided an innovative approach for advancing the development of carbide aerogels in the realm of high-temperature applications.

18.
J Agric Food Chem ; 72(21): 12119-12129, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38761152

ABSTRACT

Taurine (Tau) is a semiessential amino acid in mammals with preventive and therapeutic effects on several intestinal disorders. However, the exact function of taurine in ulcerative colitis (UC) is still largely unclear. In this study, we used two taurine-deficient mouse models (CSAD-/- and TauT-/- mice) to explore the influence of taurine on the progression of UC in both dextran sulfate sodium (DSS)-induced colitis and LPS-stimulated Caco-2 cells. We found that cysteine sulfinic acid decarboxylase (CSAD) and taurine transporter (TauT) expressions and taurine levels were markedly reduced in colonic tissues of mice treated with DSS. The CSAD and TauT knockouts exacerbated DSS-induced clinical symptoms and pathological damage and aggravated the intestinal barrier dysfunction and the colonic mucosal inflammatory response. Conversely, taurine pretreatment enhanced the intestinal barrier functions by increasing goblet cells and upregulating tight junction protein expression. Importantly, taurine bound with TLR4 and inhibited the TLR4/NF-κB pathway, ultimately reducing proinflammatory factors (TNF-α and IL-6) and oxidative stress. Our findings highlight the essential role of taurine in maintaining the intestinal barrier integrity and inhibiting intestinal inflammation, indicating that taurine is a promising supplement for colitis treatment.


Subject(s)
Colitis , Intestinal Mucosa , Mice, Inbred C57BL , Mice, Knockout , NF-kappa B , Signal Transduction , Taurine , Toll-Like Receptor 4 , Animals , Taurine/pharmacology , Taurine/administration & dosage , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism , Mice , Humans , NF-kappa B/genetics , NF-kappa B/metabolism , Signal Transduction/drug effects , Colitis/drug therapy , Colitis/metabolism , Colitis/chemically induced , Colitis/genetics , Intestinal Mucosa/metabolism , Intestinal Mucosa/drug effects , Caco-2 Cells , Male , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Dextran Sulfate/adverse effects , Carboxy-Lyases/genetics , Carboxy-Lyases/metabolism , Intestinal Barrier Function
19.
Nat Commun ; 15(1): 4176, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38755176

ABSTRACT

SETD3 is an essential host factor for the replication of a variety of enteroviruses that specifically interacts with viral protease 2A. However, the interaction between SETD3 and the 2A protease has not been fully characterized. Here, we use X-ray crystallography and cryo-electron microscopy to determine the structures of SETD3 complexed with the 2A protease of EV71 to 3.5 Å and 3.1 Å resolution, respectively. We find that the 2A protease occupies the V-shaped central cleft of SETD3 through two discrete sites. The relative positions of the two proteins vary in the crystal and cryo-EM structures, showing dynamic binding. A biolayer interferometry assay shows that the EV71 2A protease outcompetes actin for SETD3 binding. We identify key 2A residues involved in SETD3 binding and demonstrate that 2A's ability to bind SETD3 correlates with EV71 production in cells. Coimmunoprecipitation experiments in EV71 infected and 2A expressing cells indicate that 2A interferes with the SETD3-actin complex, and the disruption of this complex reduces enterovirus replication. Together, these results reveal the molecular mechanism underlying the interplay between SETD3, actin, and viral 2A during virus replication.


Subject(s)
Actins , Enterovirus A, Human , Histone Methyltransferases , Humans , Actins/metabolism , Cryoelectron Microscopy , Crystallography, X-Ray , Enterovirus A, Human/genetics , Enterovirus A, Human/metabolism , Enterovirus Infections/virology , Enterovirus Infections/metabolism , Histone-Lysine N-Methyltransferase/metabolism , Histone-Lysine N-Methyltransferase/genetics , Histone-Lysine N-Methyltransferase/chemistry , Models, Molecular , Protein Binding , Viral Proteins/metabolism , Viral Proteins/genetics , Viral Proteins/chemistry , Virus Replication
20.
Nanomaterials (Basel) ; 14(10)2024 May 13.
Article in English | MEDLINE | ID: mdl-38786804

ABSTRACT

A novel Cr-doped BaTiO3 aerogel was successfully synthesized using a co-gelation technique that involves two metallic alkoxides and a supercritical drying method. This freshly prepared aerogel has a high specific surface area of over 100 m2/g and exhibits improved responsiveness to the simulated sunlight spectrum. Methyl orange (MO) was chosen as the simulated pollutant, and the results reveal that the Cr-doped BaTiO3 aerogel, when modified with the noble metal silver (Ag), achieves a pollutant removal rate approximately 3.2 times higher than that of the commercially available P25, reaching up to 92% within 60 min. The excellent photocatalytic performance of the Ag-modified Cr-doped BaTiO3 aerogel can be primarily attributed to its extensive specific surface area and three-dimensional porous architecture. Furthermore, the incorporation of Ag nanoparticles effectively suppresses the recombination of photo-generated electrons and holes. Stability and reusability tests have confirmed the reliability of the Ag-modified Cr-doped BaTiO3 aerogel. Therefore, this material emerges as a highly promising candidate for the treatment of textile wastewater.

SELECTION OF CITATIONS
SEARCH DETAIL