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1.
Cell ; 176(6): 1447-1460.e14, 2019 03 07.
Article in English | MEDLINE | ID: mdl-30799039

ABSTRACT

The presence of DNA in the cytoplasm is normally a sign of microbial infections and is quickly detected by cyclic GMP-AMP synthase (cGAS) to elicit anti-infection immune responses. However, chronic activation of cGAS by self-DNA leads to severe autoimmune diseases for which no effective treatment is available yet. Here we report that acetylation inhibits cGAS activation and that the enforced acetylation of cGAS by aspirin robustly suppresses self-DNA-induced autoimmunity. We find that cGAS acetylation on either Lys384, Lys394, or Lys414 contributes to keeping cGAS inactive. cGAS is deacetylated in response to DNA challenges. Importantly, we show that aspirin can directly acetylate cGAS and efficiently inhibit cGAS-mediated immune responses. Finally, we demonstrate that aspirin can effectively suppress self-DNA-induced autoimmunity in Aicardi-Goutières syndrome (AGS) patient cells and in an AGS mouse model. Thus, our study reveals that acetylation contributes to cGAS activity regulation and provides a potential therapy for treating DNA-mediated autoimmune diseases.


Subject(s)
DNA/immunology , Nucleotidyltransferases/metabolism , Self Tolerance/immunology , Acetylation , Amino Acid Sequence , Animals , Aspirin/pharmacology , Autoimmune Diseases/genetics , Autoimmune Diseases/immunology , Autoimmune Diseases/metabolism , Autoimmune Diseases of the Nervous System/genetics , Autoimmune Diseases of the Nervous System/immunology , Autoimmune Diseases of the Nervous System/metabolism , Autoimmunity , Cell Line , DNA/genetics , DNA/metabolism , Disease Models, Animal , Exodeoxyribonucleases/metabolism , HEK293 Cells , HeLa Cells , Humans , Mice , Mice, Inbred C57BL , Models, Molecular , Mutation , Nervous System Malformations/genetics , Nervous System Malformations/immunology , Nervous System Malformations/metabolism , Nucleotidyltransferases/antagonists & inhibitors , Nucleotidyltransferases/chemistry , Nucleotidyltransferases/genetics , THP-1 Cells
2.
EMBO J ; 42(7): e111148, 2023 04 03.
Article in English | MEDLINE | ID: mdl-36843552

ABSTRACT

Osteoclasts are bone-resorbing polykaryons responsible for skeletal remodeling during health and disease. Coincident with their differentiation from myeloid precursors, osteoclasts undergo extensive transcriptional and metabolic reprogramming in order to acquire the cellular machinery necessary to demineralize bone and digest its interwoven extracellular matrix. While attempting to identify new regulatory molecules critical to bone resorption, we discovered that murine and human osteoclast differentiation is accompanied by the expression of Zeb1, a zinc-finger transcriptional repressor whose role in normal development is most frequently linked to the control of epithelial-mesenchymal programs. However, following targeting, we find that Zeb1 serves as an unexpected regulator of osteoclast energy metabolism. In vivo, Zeb1-null osteoclasts assume a hyperactivated state, markedly decreasing bone density due to excessive resorptive activity. Mechanistically, Zeb1 acts in a rheostat-like fashion to modulate murine and human osteoclast activity by transcriptionally repressing an ATP-buffering enzyme, mitochondrial creatine kinase 1 (MtCK1), thereby controlling the phosphocreatine energy shuttle and mitochondrial respiration. Together, these studies identify a novel Zeb1/MtCK1 axis that exerts metabolic control over bone resorption in vitro and in vivo.


Subject(s)
Bone Resorption , Osteoclasts , Mice , Animals , Humans , Osteoclasts/metabolism , Creatine Kinase, Mitochondrial Form/metabolism , Bone Resorption/genetics , Bone Resorption/metabolism , Bone and Bones , Cell Differentiation , Zinc Finger E-box-Binding Homeobox 1/genetics , Zinc Finger E-box-Binding Homeobox 1/metabolism
3.
Proc Natl Acad Sci U S A ; 121(3): e2315341121, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38190519

ABSTRACT

Wing dimorphism of insect vectors is a determining factor for viral long-distance dispersal and large-area epidemics. Although plant viruses affect the wing plasticity of insect vectors, the potential underlying molecular mechanisms have seldom been investigated. Here, we found that a planthopper-vectored rice virus, rice stripe virus (RSV), specifically induces a long-winged morph in male insects. The analysis of field populations demonstrated that the long-winged ratios of male insects are closely associated with RSV infection regardless of viral titers. A planthopper-specific and testis-highly expressed gene, Encounter, was fortuitously found to play a key role in the RSV-induced long-winged morph. Encounter resembles malate dehydrogenase in the sequence, but it does not have corresponding enzymatic activity. Encounter is upregulated to affect male wing dimorphism at early larval stages. Encounter is closely connected with the insulin/insulin-like growth factor signaling pathway as a downstream factor of Akt, of which the transcriptional level is activated in response to RSV infection, resulting in the elevated expression of Encounter. In addition, an RSV-derived small interfering RNA directly targets Encounter to enhance its expression. Our study reveals an unreported mechanism underlying the direct regulation by a plant virus of wing dimorphism in its insect vectors, providing the potential way for interrupting viral dispersal.


Subject(s)
Epidemics , Plant Viruses , Respiratory Syncytial Virus Infections , Tenuivirus , Male , Animals , Plant Viruses/genetics , Tenuivirus/genetics , Insect Vectors , Insulin-Like Peptides
4.
Nature ; 583(7818): 830-833, 2020 07.
Article in English | MEDLINE | ID: mdl-32380511

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), which has become a public health emergency of international concern1. Angiotensin-converting enzyme 2 (ACE2) is the cell-entry receptor for severe acute respiratory syndrome coronavirus (SARS-CoV)2. Here we infected transgenic mice that express human ACE2 (hereafter, hACE2 mice) with SARS-CoV-2 and studied the pathogenicity of the virus. We observed weight loss as well as virus replication in the lungs of hACE2 mice infected with SARS-CoV-2. The typical histopathology was interstitial pneumonia with infiltration of considerable numbers of macrophages and lymphocytes into the alveolar interstitium, and the accumulation of macrophages in alveolar cavities. We observed viral antigens in bronchial epithelial cells, macrophages and alveolar epithelia. These phenomena were not found in wild-type mice infected with SARS-CoV-2. Notably, we have confirmed the pathogenicity of SARS-CoV-2 in hACE2 mice. This mouse model of SARS-CoV-2 infection will be valuable for evaluating antiviral therapeutic agents and vaccines, as well as understanding the pathogenesis of COVID-19.


Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/pathology , Coronavirus Infections/virology , Lung/pathology , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Transgenes , Angiotensin-Converting Enzyme 2 , Animals , Antigens, Viral/immunology , Antigens, Viral/metabolism , Betacoronavirus/immunology , Betacoronavirus/metabolism , Bronchi/pathology , Bronchi/virology , COVID-19 , Coronavirus Infections/immunology , Disease Models, Animal , Epithelial Cells/pathology , Epithelial Cells/virology , Female , Humans , Immunoglobulin G/immunology , Lung/immunology , Lung/virology , Lymphocytes/immunology , Macrophages, Alveolar/immunology , Macrophages, Alveolar/virology , Male , Mice , Mice, Transgenic , Pandemics , Pneumonia, Viral/immunology , Receptors, Complement 3d/genetics , Receptors, Complement 3d/metabolism , SARS-CoV-2 , Virus Replication , Weight Loss
5.
Proc Natl Acad Sci U S A ; 120(39): e2305883120, 2023 Sep 26.
Article in English | MEDLINE | ID: mdl-37725637

ABSTRACT

Inspired by the development of single-atom catalysts (SACs), the fabrication of multimetallic SACs can be a promising technical approach for the in situ electro-Fenton (EF) process. Herein, dual-functional atomically dispersed Mo-Fe sites embedded in carbon nitride (C3N5) (i.e., MoFe/C3N5) were synthesized via a facile SiO2 template method. The atomically isolated bimetallic configuration in MoFe/C3N5 was identified by combining the microscopic and spectroscopic techniques. The MoFe/C3N5 catalyst on the cathode exhibited a remarkable catalytic activity toward the three electron-dominated oxygen reduction reaction in sodium sulfate, leading to a highly effective EF reaction with a low overpotential for the removal of organic contaminants from wastewater. The new catalyst showed a superior performance over its conventional counterparts, owing to the dual functions of the dual-metal active sites. Density functional theory (DFT) analysis revealed that the dual-functional 50-MoFe/C3N5 catalyst enabled a synergistic action of the Mo-Fe dual single atomic centers, which can alter the adsorption/dissociation behavior and decrease the overall reaction barriers for effective organic oxidation during the EF process. This study not only sheds light on the controlled synthesis of atomically isolated catalyst materials but also provides deeper understanding of the structure-performance relationship of the nanocatalysts with dual active sites for the catalytic EF process. Additionally, the findings will promote the advanced catalysis for the treatment of emerging organic contaminants in water and wastewater.

6.
Cereb Cortex ; 34(4)2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38602740

ABSTRACT

This study aimed to investigate the moderating role of aerobic fitness on the effect of acute exercise on improving executive function from both behavioral and cerebral aspects. Thirty-four young individuals with motor skills were divided into high- and low-fitness groups based on their maximal oxygen uptake. Both groups completed 30 min of moderate-intensity aerobic exercise on a power bike. Executive function tests (Flanker, N-back, More-odd-shifting) were performed before and after exercise and functional near-infrared spectroscopy was used to monitor prefrontal cerebral blood flow changes during the tasks. The results indicated significant differences between the two groups regarding executive function. Participants with lower aerobic fitness performed better than their higher fitness counterparts in inhibitory control and working memory, but not in cognitive flexibility. This finding suggests that the aerobic fitness may moderate the extent of cognitive benefits gained from acute aerobic exercise. Furthermore, the neuroimaging data indicated negative activation in the frontopolar area and dorsolateral prefrontal cortex in response to three complex tasks. These findings underscore the importance of considering individual aerobic fitness when assessing the cognitive benefits of exercise and could have significant implications for tailoring fitness programs to enhance cognitive performance.


Subject(s)
Executive Function , Exercise , Humans , Memory, Short-Term , Cerebrovascular Circulation , Dorsolateral Prefrontal Cortex
7.
Mol Cell ; 68(1): 185-197.e6, 2017 Oct 05.
Article in English | MEDLINE | ID: mdl-28943315

ABSTRACT

Many infections and stress signals can rapidly activate the NLRP3 inflammasome to elicit robust inflammatory responses. This activation requires a priming step, which is thought to be mainly for upregulating NLRP3 transcription. However, recent studies report that the NLRP3 inflammasome can be activated independently of transcription, suggesting that the priming process has unknown essential regulatory steps. Here, we report that JNK1-mediated NLRP3 phosphorylation at S194 is a critical priming event and is essential for NLRP3 inflammasome activation. We show that NLRP3 inflammasome activation is disrupted in NLRP3-S194A knockin mice. JNK1-mediated NLRP3 S194 phosphorylation is critical for NLRP3 deubiquitination and facilitates its self-association and the subsequent inflammasome assembly. Importantly, we demonstrate that blocking S194 phosphorylation prevents NLRP3 inflammasome activation in cryopyrin-associated periodic syndromes (CAPS). Thus, our study reveals a key priming molecular event that is a prerequisite for NLRP3 inflammasome activation. Inhibiting NLRP3 phosphorylation could be an effective treatment for NLRP3-related diseases.


Subject(s)
Inflammasomes/genetics , Macrophages/immunology , Mitogen-Activated Protein Kinase 8/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Shock, Septic/genetics , Amino Acid Sequence , Animals , Deubiquitinating Enzymes/genetics , Deubiquitinating Enzymes/immunology , Escherichia coli/chemistry , Female , Gene Expression Regulation , HEK293 Cells , Humans , Inflammasomes/immunology , Lipopolysaccharides/pharmacology , Macrophages/pathology , Male , Mice , Mice, Transgenic , Mitogen-Activated Protein Kinase 8/immunology , NLR Family, Pyrin Domain-Containing 3 Protein/deficiency , NLR Family, Pyrin Domain-Containing 3 Protein/immunology , Phosphorylation , Sequence Alignment , Sequence Homology, Amino Acid , Shock, Septic/chemically induced , Shock, Septic/mortality , Shock, Septic/pathology , Signal Transduction , Survival Analysis
8.
Cell Mol Life Sci ; 81(1): 133, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38472560

ABSTRACT

Acute lung injury (ALI) is a common clinical syndrome, which often results in pulmonary edema and respiratory distress. It has been recently reported that phosphatidylethanolamine binding protein 4 (PEBP4), a basic cytoplasmic protein, has anti-inflammatory and hepatoprotective effects, but its relationship with ALI remains undefined so far. In this study, we generated PEBP4 knockout (KO) mice to investigate the potential function of PEBP4, as well as to evaluate the capacity of alveolar fluid clearance (AFC) and the activity of phosphatidylinositide 3-kinases (PI3K)/serine-theronine protein kinase B (PKB, also known as AKT) signaling pathway in lipopolysaccharide (LPS)-induced ALI mice models. We found that PEBP4 deficiency exacerbated lung pathological damage and edema, and increased the wet/dry weight ratio and total protein concentration of bronchoalveolar lavage fluid (BALF) in LPS-treated mice. Meanwhile, PEBP4 KO promoted an LPS-induced rise in the pulmonary myeloperoxidase (MPO) activity, serum interleuin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α levels, and pulmonary cyclooxygenase-2 (COX-2) expression. Mechanically, PEBP4 deletion further reduced the protein expression of Na+ transport markers, including epithelial sodium channel (ENaC)-α, ENaC-γ, Na,K-ATPase α1, and Na,K-ATPase ß1, and strengthened the inhibition of PI3K/AKT signaling in LPS-challenged mice. Furthermore, we demonstrated that selective activation of PI3K/AKT with 740YP or SC79 partially reversed all of the above effects caused by PEBP4 KO in LPS-treated mice. Altogether, our results indicated the PEBP4 deletion has a deterioration effect on LPS-induced ALI by impairing the capacity of AFC, which may be achieved through modulating the PI3K/AKT pathway.


Subject(s)
Acute Lung Injury , Lipopolysaccharides , Animals , Mice , Acute Lung Injury/chemically induced , Lipopolysaccharides/pharmacology , Lung/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Sodium-Potassium-Exchanging ATPase/metabolism , Sodium-Potassium-Exchanging ATPase/pharmacology , Sodium-Potassium-Exchanging ATPase/therapeutic use , Tumor Necrosis Factor-alpha/metabolism
9.
Nano Lett ; 24(27): 8351-8360, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38916238

ABSTRACT

Targeting telomere maintenance has emerged as a promising strategy for hepatocellular carcinoma (HCC) treatment. However, given the duality of the telomere-telomerase axis in telomere maintenance, a comprehensive strategy is urgently needed. Herein, we develop a poly(amino acid) (D-PAAs)-based strategy for spatiotemporal codelivery of telomerase inhibitor, BIBR1523, and AKT inhibitor, isobavachalcone. By leveraging D-PAAs' modifiability, we synthesize polymer-inhibitor conjugates (PB and PI) and a folic acid-decorated tumor-targeting vector (PF). These building blocks undergo micellization to fabricate a codelivery nanomedicine (P-BI@P-FA) by exploiting D-PAAs' noncovalent assembly. P-BI@P-FA improves the pharmacokinetics, tumor selectivity, and bioavailability of small molecule inhibitors and initiates a dual telomere-specific inhibition by combining telomerase deactivation with telomere disruption. Furthermore, a hybrid tumor-targeting magnetic nanosystem is designed using D-PAAs and manganese dioxide to showcase magnetic resonance imaging capacities. Our D-PAAs-based strategy addresses the pressing need for telomere-specific HCC treatment while allowing for diagnostic application, presenting a promising avenue for nanomedicine design.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Magnetic Resonance Imaging , Nanomedicine , Telomerase , Telomere , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/pathology , Telomerase/antagonists & inhibitors , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/drug therapy , Humans , Nanomedicine/methods , Telomere/metabolism , Magnetic Resonance Imaging/methods , Animals , Mice , Cell Line, Tumor , Amino Acids/chemistry , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/therapeutic use
10.
Lancet Oncol ; 25(2): 184-197, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38211606

ABSTRACT

BACKGROUND: Triple-negative breast cancers display heterogeneity in molecular drivers and immune traits. We previously classified triple-negative breast cancers into four subtypes: luminal androgen receptor (LAR), immunomodulatory, basal-like immune-suppressed (BLIS), and mesenchymal-like (MES). Here, we aimed to evaluate the efficacy and safety of subtyping-based therapy in the first-line treatment of triple-negative breast cancer. METHODS: FUTURE-SUPER is an ongoing, open-label, randomised, controlled phase 2 trial being conducted at Fudan University Shanghai Cancer Center (FUSCC), Shanghai, China. Eligible participants were females aged 18-70 years, with an Eastern Cooperative Oncology Group performance status of 0-1, and histologically confirmed, untreated metastatic or recurrent triple-negative breast cancer. After categorising participants into five cohorts according to molecular subtype and genomic biomarkers, participants were randomly assigned (1:1) with a block size of 4, stratified by subtype, to receive, in 28-day cycles, nab-paclitaxel (100 mg/m2, intravenously on days 1, 8, and 15) alone (control group) or with a subtyping-based regimen (subtyping-based group): pyrotinib (400 mg orally daily) for the LAR-HER2mut subtype, everolimus (10 mg orally daily) for the LAR-PI3K/AKTmut and MES-PI3K/AKTmut subtypes, camrelizumab (200 mg intravenously on days 1 and 15) and famitinib (20 mg orally daily) for the immunomodulatory subtype, and bevacizumab (10 mg/kg intravenously on days 1 and 15) for the BLIS/MES-PI3K/AKTWT subtype. The primary endpoint was investigator-assessed progression-free survival for the pooled subtyping-based group versus the control group in the intention-to-treat population (all randomly assigned participants). Safety was analysed in all patients with safety records who received at least one dose of study drug. This study is registered with ClinicalTrials.gov (NCT04395989). FINDINGS: Between July 28, 2020, and Oct 16, 2022, 139 female participants were enrolled and randomly assigned to the subtyping-based group (n=69) or control group (n=70). At the data cutoff (May 31, 2023), the median follow-up was 22·5 months (IQR 15·2-29·0). Median progression-free survival was significantly longer in the pooled subtyping-based group (11·3 months [95% CI 8·6-15·2]) than in the control group (5·8 months [4·0-6·7]; hazard ratio 0·44 [95% CI 0·30-0·65]; p<0·0001). The most common grade 3-4 treatment-related adverse events were neutropenia (21 [30%] of 69 in the pooled subtyping-based group vs 16 [23%] of 70 in the control group), anaemia (five [7%] vs none), and increased alanine aminotransferase (four [6%] vs one [1%]). Treatment-related serious adverse events were reported for seven (10%) of 69 patients in the subtyping-based group and none in the control group. No treatment-related deaths were reported in either group. INTERPRETATION: These findings highlight the potential clinical benefits of using molecular subtype-based treatment optimisation in patients with triple-negative breast cancer, suggesting a path for further clinical investigation. Phase 3 randomised clinical trials assessing the efficacy of subtyping-based regimens are now underway. FUNDING: National Natural Science Foundation of China, Natural Science Foundation of Shanghai, Shanghai Hospital Development Center, and Jiangsu Hengrui Pharmaceuticals. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Subject(s)
Triple Negative Breast Neoplasms , Humans , Female , Triple Negative Breast Neoplasms/drug therapy , Triple Negative Breast Neoplasms/pathology , Proto-Oncogene Proteins c-akt , Phosphatidylinositol 3-Kinases/therapeutic use , Neoplasm Recurrence, Local/drug therapy , China , Antineoplastic Combined Chemotherapy Protocols/adverse effects
11.
J Proteome Res ; 2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39037832

ABSTRACT

Dental caries is a chronic oral infectious disease, and Streptococcus mutans (S. mutans) plays an important role in the formation of dental caries. Trans-cinnamaldehyde (CA) exhibits broad-spectrum antibacterial activity; however, its target and mechanism of action of CA on S. mutans needs to be further explored. In this study, it was verified that CA could inhibit the growth and biofilm formation of S. mutans. Further proteomic analysis identified 33, 55, and 78 differentially expressed proteins (DEPs) in S. mutans treated with CA for 1, 2, and 4 h, respectively. Bioinformatics analysis showed that CA interfered with carbohydrate metabolism, glycolysis, pyruvate metabolism, and the TCA cycle, as well as amino acid metabolism of S. mutans. Protein interactions suggested that pyruvate dehydrogenase (PDH) plays an important role in the antibacterial effect of CA. Moreover, the upstream and downstream pathways related to PDH were verified by various assays, and the results proved that CA not only suppressed the glucose and sucrose consumption and inhibited glucosyltransferase (GTF) and lactate dehydrogenase (LDH) activities but also decreased the ATP production. Interestingly, the protein interaction, qRT-PCR, and molecular docking analysis showed that PDH might be the target of CA to fight S. mutans. In summary, the study shows that CA interferes with the carbohydrate metabolism of bacteria by inhibiting glycolysis and the tricarboxylic acid (TCA) cycle via binding to PDH, which verifies that PDH is a potential target for the development of new drugs against S. mutans.

12.
J Biol Chem ; 299(12): 105481, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38041932

ABSTRACT

Singlet oxygen (1O2) has a very short half-life of 10-5 s; however, it is a strong oxidant that causes growth arrest and necrotic lesions on plants. Its signaling pathway remains largely unknown. The Arabidopsis flu (fluorescent) mutant accumulates a high level of 1O2 and shows drastic changes in nuclear gene expression. Only two plastid proteins, EX1 (executer 1) and EX2 (executer 2), have been identified in the singlet oxygen signaling. Here, we found that the transcription factor abscisic acid insensitive 4 (ABI4) binds the promoters of genes responsive to 1O2-signals. Inactivation of the ABI4 protein in the flu/abi4 double mutant was sufficient to compromise the changes of almost all 1O2-responsive-genes and rescued the lethal phenotype of flu grown under light/dark cycles, similar to the flu/ex1/ex2 triple mutant. In addition to cell death, we reported for the first time that 1O2 also induces cell wall thickening and stomatal development defect. Contrastingly, no apparent growth arrest was observed for the flu mutant under normal light/dim light cycles, but the cell wall thickening (doubled) and stomatal density reduction (by two-thirds) still occurred. These results offer a new idea for breeding stress tolerant plants.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Abscisic Acid/metabolism , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Cell Wall/metabolism , Gene Expression Regulation, Plant , Light , Singlet Oxygen/metabolism , Transcriptome , Plant Stomata/metabolism
13.
Immunology ; 172(3): 486-499, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38547355

ABSTRACT

To explore the effect of K33 only mutant ubiquitin (K33O) on bone marrow-derived dendritic cells' (BMDCs') maturity, antigen uptake capability, surface molecule expressions and BMDC-mediated CTL priming, and further investigate the role of PI3K-Akt engaged in K33O-increased BMDC maturation, antigen uptake and presentation, surface molecule expressions and BMDC-based CTL priming. BMDCs were conferred K33O and other ubiquitin mutants (K33R, K48R, K63R-mutant ubiquitin) incubation or LY294002 and wortmannin pretreatment. PI3K-Akt phosphorylation, antigen uptake, antigenic presentation and CD86/MHC class I expression in BMDC were determined by western blot or flow cytometry. BMDC-based CTL proliferation and priming were determined by in vitro mixed lymphocyte reaction (MLR), ex vivo enzyme-linked immunospot assay (Elispot) and flow cytometry with intracellular staining, respectively. The treatment with K33O effectively augmented PI3K-Akt phosphorylation, BMDCs' antigen uptake, antigenic presentation, CD86/MHC class I and CD11c expressions. MLR, Elispot and flow cytometry revealed that K33O treatment obviously enhanced CTL proliferation, CTL priming and perforin/granzyme B expression. The pretreatment with PI3K-Akt inhibitors efficiently abrogated K33O's effects on BMDC. The replenishment of K33 only mutant ubiquitin augments BMDC-mediated CTL priming in bone marrow-derived dendritic cells via PI3K-Akt signalling.


Subject(s)
Antigen Presentation , Bone Marrow Cells , Dendritic Cells , Phosphatidylinositol 3-Kinases , Proto-Oncogene Proteins c-akt , Signal Transduction , T-Lymphocytes, Cytotoxic , Ubiquitin , Dendritic Cells/immunology , Dendritic Cells/metabolism , Animals , Mice , Proto-Oncogene Proteins c-akt/metabolism , Ubiquitin/metabolism , T-Lymphocytes, Cytotoxic/immunology , Bone Marrow Cells/immunology , Bone Marrow Cells/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Antigen Presentation/immunology , Mice, Inbred C57BL , Phosphorylation , Lymphocyte Activation , Cell Differentiation , Mutation , Morpholines/pharmacology , Lymphocyte Culture Test, Mixed , Cell Proliferation , B7-2 Antigen/metabolism , B7-2 Antigen/genetics , B7-2 Antigen/immunology , Cells, Cultured , Chromones/pharmacology , Wortmannin/pharmacology , Androstadienes/pharmacology
14.
J Am Chem Soc ; 146(5): 2919-2927, 2024 Feb 07.
Article in English | MEDLINE | ID: mdl-38277794

ABSTRACT

Dicarboxylic acids and derivatives are important building blocks in organic synthesis, biochemistry, and the polymer industry. Although catalytic dicarboxylation with CO2 represents a straightforward and sustainable route to dicarboxylic acids, it is still highly challenging and limited to generation of achiral or racemic dicarboxylic acids. To date, catalytic asymmetric dicarboxylation with CO2 to give chiral dicarboxylic acids has not been reported. Herein, we report the first asymmetric dicarboxylation of 1,3-dienes with CO2 via Cu catalysis. This strategy provides an efficient and environmentally benign route to chiral dicarboxylic acids with high regio-, chemo-, and enantioselectivities. The copper self-relay catalysis, that is, Cu-catalyzed boracarboxylation of 1,3-dienes to give carboxylated allyl boronic ester intermediates and subsequent carboxylation of C-B bonds to give dicarboxylates, is key to the success of this dicarboxylation. Moreover, this protocol exhibits broad substrate scope, good functional group tolerance, easy product derivatizations, and facile synthesis of chiral liquid crystalline polyester and drug-like scaffolds.

15.
J Am Chem Soc ; 146(20): 14267-14277, 2024 May 22.
Article in English | MEDLINE | ID: mdl-38717595

ABSTRACT

Converting CO2 to synthetic hydrocarbon fuels is of increasing interest. In light of progress in electrified CO2 to ethylene, we explored routes to dimerize to 1-butene, an olefin that can serve as a building block to ethylene longer-chain alkanes. With goal of selective and active dimerization, we investigate a series of metal-organic frameworks having bimetallic catalytic sites. We find that the tunable pore structure enables optimization of selectivity and that periodic pore channels enhance activity. In a tandem system for the conversion of CO2 to 1-C4H8, wherein the outlet cathodic gas from a CO2-to-C2H4 electrolyzer is fed directly (via a dehumidification stage) into the C2H4 dimerizer, we study the highest-performing MOF found herein: M' = Ru and M″ = Ni in the bimetallic two-dimensional M'2(OAc)4M″(CN)4 MOF. We report a 1-C4H8 production rate of 1.3 mol gcat-1 h-1 and a C2H4 conversion of 97%. From these experimental data, we project an estimated cradle-to-gate carbon intensity of -2.1 kg-CO2e/kg-1-C4H8 when CO2 is supplied from direct air capture and when the required energy is supplied by electricity having the carbon intensity of wind.

16.
J Am Chem Soc ; 146(12): 8641-8649, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38470826

ABSTRACT

Renewable-energy-powered electrosynthesis has the potential to contribute to decarbonizing the production of propylene glycol, a chemical that is used currently in the manufacture of polyesters and antifreeze and has a high carbon intensity. Unfortunately, to date, the electrooxidation of propylene under ambient conditions has suffered from a wide product distribution, leading to a low faradic efficiency toward the desired propylene glycol. We undertook mechanistic investigations and found that the reconstruction of Pd to PdO occurs, followed by hydroxide formation under anodic bias. The formation of this metastable hydroxide layer arrests the progressive dissolution of Pd in a locally acidic environment, increases the activity, and steers the reaction pathway toward propylene glycol. Rh-doped Pd further improves propylene glycol selectivity. Density functional theory (DFT) suggests that the Rh dopant lowers the energy associated with the production of the final intermediate in propylene glycol formation and renders the desorption step spontaneous, a concept consistent with experimental studies. We report a 75% faradic efficiency toward propylene glycol maintained over 100 h of operation.

17.
Emerg Infect Dis ; 30(2): 321-324, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38270156

ABSTRACT

Among persons born in China before 1980 and tested for vaccinia virus Tiantan strain (VVT), 28.7% (137/478) had neutralizing antibodies, 71.4% (25/35) had memory B-cell responses, and 65.7% (23/35) had memory T-cell responses to VVT. Because of cross-immunity between the viruses, these findings can help guide mpox vaccination strategies in China.


Subject(s)
Mpox (monkeypox) , Smallpox , Humans , Smallpox/prevention & control , Vaccination , Antibodies, Neutralizing , China/epidemiology , Vaccinia virus
18.
Br J Haematol ; 204(4): 1307-1324, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38462771

ABSTRACT

Multiple myeloma (MM) is the second most common malignant haematological disease with a poor prognosis. The limit therapeutic progress has been made in MM patients with cancer relapse, necessitating deeper research into the molecular mechanisms underlying its occurrence and development. A genome-wide CRISPR-Cas9 loss-of-function screening was utilized to identify potential therapeutic targets in our research. We revealed that COQ2 plays a crucial role in regulating MM cell proliferation and lipid peroxidation (LPO). Knockout of COQ2 inhibited cell proliferation, induced cell cycle arrest and reduced tumour growth in vivo. Mechanistically, COQ2 promoted the activation of the MEK/ERK cascade, which in turn stabilized and activated MYC protein. Moreover, we found that COQ2-deficient MM cells increased sensitivity to the LPO activator, RSL3. Using an inhibitor targeting COQ2 by 4-CBA enhanced the sensitivity to RSL3 in primary CD138+ myeloma cells and in a xenograft mouse model. Nevertheless, co-treatment of 4-CBA and RSL3 induced cell death in bortezomib-resistant MM cells. Together, our findings suggest that COQ2 promotes cell proliferation and tumour growth through the activation of the MEK/ERK/MYC axis and targeting COQ2 could enhance the sensitivity to ferroptosis in MM cells, which may be a promising therapeutic strategy for the treatment of MM patients.


Subject(s)
Multiple Myeloma , Animals , Humans , Mice , Cell Line, Tumor , Cell Proliferation , CRISPR-Cas Systems , Disease Models, Animal , Lipid Peroxidation , Mitogen-Activated Protein Kinase Kinases/therapeutic use , Multiple Myeloma/drug therapy
19.
Biochem Biophys Res Commun ; 719: 150127, 2024 Jul 30.
Article in English | MEDLINE | ID: mdl-38761634

ABSTRACT

Alzheimer's disease is characterized by abnormal ß-amyloid and tau accumulation, mitochondrial dysfunction, oxidative stress, and synaptic dysfunction. Here, we aimed to assess the mechanisms and signalling pathways in the neuroprotective effect of gastrodin, a phenolic glycoside, on murine neuroblastoma N2a cells expressing human Swedish mutant APP (N2a/APP). We found that gastrodin increased the levels of presynaptic-SNAP, synaptophysin, and postsynaptic-PSD95 and reduced phospho-tau Ser396, APP and Aß1-42 levels in N2a/APP cells. Gastrodin treatment reduced reactive oxygen species generation, lipid peroxidation, mitochondrial fragmentation and DNA oxidation; restored mitochondrial membrane potential and intracellular ATP production. Upregulated phospho-GSK-3ß and reduced phospho-ERK and phospho-JNK were involved in the protective effect of gastrodin. In conclusion, we demonstrated the neuroprotective effect of gastrodin in the N2a/APP cell line by ameliorating the impairment on synaptic and mitochondrial function, reducing tau phosphorylation, Aß1-42 levels as well as reactive oxygen species generation. These results provide new mechanistic insights into the potential effect of gastrodin in the treatment of Alzheimer's disease.


Subject(s)
Benzyl Alcohols , Glucosides , Mitochondria , Neuroprotective Agents , Oxidative Stress , Reactive Oxygen Species , Synapses , Glucosides/pharmacology , Benzyl Alcohols/pharmacology , Oxidative Stress/drug effects , Animals , Mice , Mitochondria/drug effects , Mitochondria/metabolism , Neuroprotective Agents/pharmacology , Cell Line, Tumor , Reactive Oxygen Species/metabolism , Synapses/drug effects , Synapses/metabolism , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/metabolism , Amyloid beta-Protein Precursor/genetics , Humans , Alzheimer Disease/metabolism , Alzheimer Disease/drug therapy , Alzheimer Disease/pathology , tau Proteins/metabolism , Membrane Potential, Mitochondrial/drug effects , Peptide Fragments
20.
Biochem Biophys Res Commun ; 693: 149199, 2024 Jan 22.
Article in English | MEDLINE | ID: mdl-38118311

ABSTRACT

With economic development and overnutrition, including high-fat diets (HFD) and high-glucose diets (HGD), the incidence of obesity in children is increasing, and thus, the incidence of precocious puberty is increasing. Therefore, it is of great importance to construct a suitable animal model of overnutrition-induced precocious puberty for further in-depth study. Here, we fed a HFD, HGD, or HFD combined with a HGD to pups after P-21 weaning, while weaned pups fed a normal diet served as the control group. The results showed that HFD combined with a HGD increased the body weight (BW) of weaned rat pups. In addition, a HFD, HGD, and HFD combined with a HGD lowered the age at which vaginal opening occurred and accelerated the vaginal cell cycle. Furthermore, a HFD combined with a HGD increased the weight of the uterus and ovaries of weaned rat pups. Additionally, a HFD combined with a HGD promoted the development of reproductive organs in weaned female rat pups. Ultimately, a HFD combined with a HGD was found to elevate the serum levels of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), follicle stimulating hormone (FSH), leptin, adiponectin, and oestradiol (E2) and increase hypothalamic GnRH, Kiss-1, and GPR54 expression levels in weaned female rat pups. The current study found that overnutrition, such as that through a HFD combined with HGD, could induce precocious puberty in weaned female rat pups. In addition, a rat model of overnutrition-induced precocious puberty was established.


Subject(s)
Pediatric Obesity , Puberty, Precocious , Humans , Child , Animals , Rats , Female , Rats, Sprague-Dawley , Puberty, Precocious/chemically induced , Pediatric Obesity/complications , Gonadotropin-Releasing Hormone , Diet, High-Fat/adverse effects , Glucose
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