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1.
Sci Rep ; 14(1): 21860, 2024 09 19.
Article de Anglais | MEDLINE | ID: mdl-39300102

RÉSUMÉ

No single treatment significantly reduces the mortality rate and improves neurological outcomes after intracerebral haemorrhage (ICH). New evidence suggests that pyroptosis-specific proteins are highly expressed in the perihaematomal tissues of patients with ICH and that the disulfiram (DSF) inhibits pyroptosis. An ICH model was established in C57BL/6 mice by intracranial injection of collagenase, after which DSF was used to treat the mice. Cell model of ICH was constructed, and DSF was used to treat the cells. HE, TUNEL, Nissl, FJC and IF staining were performed to evaluate the morphology of brain tissues; Western blotting and ELISA were performed to measure the protein expression of NOD-like receptor protein 3 (NLRP3)/Caspase-1/gasdermin D (GSDMD) classical pyroptosis pathway and Toll-likereceptor4 (TLR4)/nuclear factor-kappaB (NF-κB) inflammatory signaling pathway and blood‒brain barrier-associated factoes, and the wet/dry weight method was used to determine the brain water content. The expression of proteins related to the NLRP3/Caspase-1/GSDMD pathway and the TLR4/NF-κB pathway was upregulated in tissues surrounding the haematoma compared with that in control tissues; Moreover, the expression of the blood-brain barrier structural proteins occludin and zonula occludens-1 (ZO-1) was downregulated, and the expression of Aquaporin Protein-4 (AQP4) and matrix metalloprotein 9 (MMP-9) was upregulated. DSF significantly inhibited these changes, reduced the haematoma volume, decreased the brain water content, reduced neuronal death and degeneration and improved neurological function after ICH. ICH activated the classical pyroptosis pathway and TLR4/NF-κB inflammatory pathway, disruped the expression of blood-brain barrier structural proteins, and exacerbated brain injury and neurological dysfunction. DSF inhibited these changes and exerted the therapeutic effects on pathological changes and dysfunction caused by ICH.


Sujet(s)
Barrière hémato-encéphalique , Disulfirame , Souris de lignée C57BL , Facteur de transcription NF-kappa B , Protéine-3 de la famille des NLR contenant un domaine pyrine , Pyroptose , Transduction du signal , Récepteur de type Toll-4 , Animaux , Pyroptose/effets des médicaments et des substances chimiques , Barrière hémato-encéphalique/effets des médicaments et des substances chimiques , Barrière hémato-encéphalique/métabolisme , Souris , Protéine-3 de la famille des NLR contenant un domaine pyrine/métabolisme , Disulfirame/pharmacologie , Transduction du signal/effets des médicaments et des substances chimiques , Mâle , Récepteur de type Toll-4/métabolisme , Facteur de transcription NF-kappa B/métabolisme , Modèles animaux de maladie humaine , Caspase-1/métabolisme , Protéines de liaison aux phosphates/métabolisme , Hémorragies intracrâniennes/traitement médicamenteux , Hémorragies intracrâniennes/métabolisme , Occludine/métabolisme , Protéine-1 de la zonula occludens/métabolisme , Matrix metalloproteinase 9/métabolisme , Humains , Gasdermines
2.
Angew Chem Int Ed Engl ; : e202413413, 2024 Sep 07.
Article de Anglais | MEDLINE | ID: mdl-39243218

RÉSUMÉ

π frameworks, defined as a type of porous supramolecular materials weaved from conjugated molecular units by π-π stacking interactions, provide a new direction in photocatalysis. However, such examples are rarely reported. Herein, we report a supramolecular-nanocage-based π framework constructed from a photoactive Cu(I) complex unit. Structurally, 24 Cu(I) complex units stack together through π-π stacking interactions, forming a truncated octahedral nanocage with sodalite topology. The inner diameter of the nanocage is 2.8 nm. By sharing four open faces, each nanocage connects with four equivalent ones, forming a 3D porous π framework (π-2). π-2 shows good thermal and chemical stability, which can adsorb CO2, iodine, and methyl orange molecules. More importantly, π-2 can serve as a photocatalyst for hydrogen evolution reaction. With ultrafine Pt subnanometer particles (0.9±0.1 nm) incorporated into the nanocages as a co-catalyst, the hydrogen evolution rate reaches a record-high value of 517551 µmol/gPt/h in the absence of any additional photosensitizers. The high photocatalytic activity can be ascribed to the ultrafine size of the Pt particles, as well as the fast electron transfer from π-2 to the highly active Pt upon illumination. π-2 represents the unique stable supramolecular-cage-based π framework with excellent photocatalytic activity.

3.
Inorg Chem ; 63(36): 16897-16907, 2024 Sep 09.
Article de Anglais | MEDLINE | ID: mdl-39197012

RÉSUMÉ

Exploiting a photocatalyst with high stability and excellent activity for Cr(VI) reduction under mild conditions is crucial yet challenging. Herein, the rigid aromatic multicarboxylate ligand with chromophore anthracene was selected to coordinate with multivalent metal ion manganese and to obtain a stable two-dimensional (2D) Mn-based metal-organic framework (MOF), LCUH-120, which can efficiently and quickly convert Cr(VI) into Cr(III) under light without the need for any additional photosensitizer. The efficient photosensitive anthracene group serves as a photosensitizer center and multivalent Mn(II) ion as a photocatalyst center in LCUH-120, and the conversion of Cr(VI) to Cr(III) can be realized completely in just 40 min. Specifically, the rate constant (k) and reduction rate of the Cr(VI) photocatalytic reaction can be high up to 0.134 min-1 and 2.50 mgCr(VI) g-1cata min-1 in an acidic environment (pH = 2), respectively. Compared to our previously reported three-dimensional (3D) Sm-MOF, LCUH-120 exhibits a significantly higher catalytic reaction rate, which might be ascribed to the fact that the photocatalyst center Mn node can improve the rate of electron transfer and promote the separation of holes and photogenerated electrons. In an acidic environment, the reaction mechanism can be verified through various contrast experiments and theoretical simulations.

4.
J Cell Mol Med ; 28(16): e70004, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39159174

RÉSUMÉ

Ischemia and hypoxia activate astrocytes into reactive types A1 and A2, which play roles in damage and protection, respectively. However, the function and mechanism of A1 and A2 astrocyte exosomes are unknown. After astrocyte exosomes were injected into the lateral ventricle, infarct volume, damage to the blood-brain barrier (BBB), apoptosis and the expression of microglia-related proteins were measured. The dual luciferase reporter assay was used to detect the target genes of miR-628, and overexpressing A2-Exos overexpressed and knocked down miR-628 were constructed. qRT-PCR, western blotting and immunofluorescence staining were subsequently performed. A2-Exos obviously reduced the infarct volume, damage to the BBB and apoptosis and promoted M2 microglial polarization. RT-PCR showed that miR-628 was highly expressed in A2-Exos. Dual luciferase reporter assays revealed that NLRP3, S1PR3 and IRF5 are target genes of miR-628. After miR-628 was overexpressed or knocked down, the protective effects of A2-Exos increased or decreased, respectively. A2-Exos reduced pyroptosis and BBB damage and promoted M2 microglial polarization through the inhibition of NLRP3, S1PR3 and IRF5 via the delivery of miR-628. This study explored the mechanism of action of A2-Exos and provided new therapeutic targets and concepts for treating cerebral ischemia.


Sujet(s)
Astrocytes , Barrière hémato-encéphalique , Encéphalopathie ischémique , Exosomes , microARN , Lésion d'ischémie-reperfusion , microARN/génétique , microARN/métabolisme , Animaux , Astrocytes/métabolisme , Lésion d'ischémie-reperfusion/métabolisme , Lésion d'ischémie-reperfusion/génétique , Lésion d'ischémie-reperfusion/anatomopathologie , Lésion d'ischémie-reperfusion/thérapie , Exosomes/métabolisme , Encéphalopathie ischémique/métabolisme , Encéphalopathie ischémique/génétique , Encéphalopathie ischémique/thérapie , Encéphalopathie ischémique/anatomopathologie , Barrière hémato-encéphalique/métabolisme , Mâle , Apoptose/génétique , Microglie/métabolisme , Microglie/anatomopathologie , Souris
5.
Angew Chem Int Ed Engl ; 63(36): e202405451, 2024 Sep 02.
Article de Anglais | MEDLINE | ID: mdl-39031893

RÉSUMÉ

Hydrogen-bonded organic frameworks (HOFs) are outstanding candidates for photocatalytic hydrogen evolution. However, most of reported HOFs suffer from poor stability and photocatalytic activity in the absence of Pt cocatalyst. Herein, a series of metal HOFs (Co2-HOF-X, X=COOMe, Br, tBu and OMe) have been rationally constructed based on dinuclear cobalt complexes, which exhibit exceptional stability in the presence of strong acid (12 M HCl) and strong base (5 M NaOH) for at least 10 days. More impressively, by varying the -X groups of the dinuclear cobalt complexes, the microenvironment of Co2-HOF-X can be modulated, giving rise to obviously different photocatalytic H2 production rates, following the -X group sequence of -COOMe>-Br>-tBu>-OMe. The optimized Co2-HOF-COOMe shows H2 generation rate up to 12.8 mmol g-1 h-1 in the absence of any additional noble-metal photosensitizers and cocatalysts, which is superior to most reported Pt-assisted photocatalytic systems. Experiments and theoretical calculations reveal that the -X groups grafted on Co2-HOF-X possess different electron-withdrawing ability, thus regulating the electronic structures of Co catalytic centres and proton activation barrier for H2 production, and leading to the distinctly different photocatalytic activity.

6.
Angew Chem Int Ed Engl ; : e202411639, 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38976517

RÉSUMÉ

Dinuclear metal synergistic catalysis (DMSC) has been proved an effective approach to enhance catalytic efficiency in photocatalytic CO2 reduction reaction, while it remains challenge to design dinuclear metal complexes that can show DMSC effect. The main reason is that the influence of the microenvironment around dinuclear metal centres on catalytic activity has not been well recognized and revealed. Herein, we report a dinuclear cobalt complex featuring a planar structure, which displays outstanding catalytic efficiency for photochemical CO2-to-CO conversion. The turnover number (TON) and turnover frequency (TOF) values reach as high as 14457 and 0.40 s-1 respectively, 8.6 times higher than those of the corresponding mononuclear cobalt complex. Control experiments and theoretical calculations revealed that the enhanced catalytic efficiency of the dinuclear cobalt complex is due to the indirect DMSC effect between two CoII ions, energetically feasible one step two-electron transfer process by Co2 I,I intermediate to afford Co2 II,II(CO2 2-) intermediate and fast mass transfer closely related with the planar structure.

7.
Biomaterials ; 311: 122695, 2024 Dec.
Article de Anglais | MEDLINE | ID: mdl-38954960

RÉSUMÉ

Integrating immunotherapy with nanomaterials-based chemotherapy presents a promising avenue for amplifying antitumor outcomes. Nevertheless, the suppressive tumor immune microenvironment (TIME) and the upregulation of cyclooxygenase-2 (COX-2) induced by chemotherapy can hinder the efficacy of the chemoimmunotherapy. This study presents a TIME-reshaping strategy by developing a steric-hindrance effect tuned zinc-based metal-organic framework (MOF), designated as CZFNPs. This nanoreactor is engineered by in situ loading of the COX-2 inhibitor, C-phycocyanin (CPC), into the framework building blocks, while simultaneously weakening the stability of the MOF. Consequently, CZFNPs achieve rapid pH-responsive release of zinc ions (Zn2+) and CPC upon specific transport to tumor cells overexpressing folate receptors. Accordingly, Zn2+ can induce reactive oxygen species (ROS)-mediated cytotoxicity therapy while synchronize with mitochondrial DNA (mtDNA) release, which stimulates mtDNA/cGAS-STING pathway-mediated innate immunity. The CPC suppresses the chemotherapy-induced overexpression of COX-2, thus cooperatively reprogramming the suppressive TIME and boosting the antitumor immune response. In xenograft tumor models, the CZFNPs system effectively modulates STING and COX-2 expression, converting "cold" tumors into "hot" tumors, thereby resulting in ≈ 4-fold tumor regression relative to ZIF-8 treatment alone. This approach offers a potent strategy for enhancing the efficacy of combined nanomaterial-based chemotherapy and immunotherapy.


Sujet(s)
Inhibiteurs de la cyclooxygénase 2 , Cyclooxygenase 2 , Immunothérapie , Protéines membranaires , Réseaux organométalliques , Animaux , Immunothérapie/méthodes , Cyclooxygenase 2/métabolisme , Humains , Réseaux organométalliques/composition chimique , Réseaux organométalliques/pharmacologie , Protéines membranaires/métabolisme , Lignée cellulaire tumorale , Souris , Inhibiteurs de la cyclooxygénase 2/pharmacologie , Inhibiteurs de la cyclooxygénase 2/usage thérapeutique , Souris de lignée BALB C , Espèces réactives de l'oxygène/métabolisme , Nanoparticules/composition chimique , Tumeurs/traitement médicamenteux , Tumeurs/thérapie , Femelle , Microenvironnement tumoral/effets des médicaments et des substances chimiques
8.
Bioorg Chem ; 150: 107584, 2024 Sep.
Article de Anglais | MEDLINE | ID: mdl-38964146

RÉSUMÉ

Developing multitargeted ligands as promising therapeutics for Alzheimer's disease (AD) has been considered important. Herein, a novel class of cinnamamide/ester-triazole hybrids with multifaceted effects on AD was developed based on the multitarget-directed ligands strategy. Thirty-seven cinnamamide/ester-triazole hybrids were synthesized, with most exhibiting significant inhibitory activity against Aß-induced toxicity at a single concentration in vitro. The most optimal hybrid compound 4j inhibited copper-induced Aß toxicity in AD cells. its action was superior to that of donepezil and memantine. It also moderately inhibited intracellular AChE activity and presented favorable bioavailability and blood-brain barrier penetration with low toxicity in vivo. Of note, it ameliorated cognitive impairment, neuronal degeneration, and Aß deposition in Aß1-42-injured mice. Mechanistically, the compound regulated APP processing by promoting the ADAM10-associated nonamyloidogenic signaling and inhibiting the BACE1-mediated amyloidogenic pathway. Moreover, it suppressed intracellular AChE activity and tau phosphorylation. Therefore, compound 4j may be a promising multitargeted active molecule against AD.


Sujet(s)
Maladie d'Alzheimer , Peptides bêta-amyloïdes , Cinnamates , Triazoles , Maladie d'Alzheimer/traitement médicamenteux , Maladie d'Alzheimer/métabolisme , Animaux , Triazoles/composition chimique , Triazoles/pharmacologie , Triazoles/synthèse chimique , Cinnamates/composition chimique , Cinnamates/pharmacologie , Cinnamates/synthèse chimique , Humains , Souris , Peptides bêta-amyloïdes/métabolisme , Peptides bêta-amyloïdes/antagonistes et inhibiteurs , Relation structure-activité , Structure moléculaire , Esters/composition chimique , Esters/pharmacologie , Esters/synthèse chimique , Relation dose-effet des médicaments , Acetylcholinesterase/métabolisme , Anticholinestérasiques/composition chimique , Anticholinestérasiques/pharmacologie , Anticholinestérasiques/synthèse chimique , Découverte de médicament , Neuroprotecteurs/composition chimique , Neuroprotecteurs/pharmacologie , Neuroprotecteurs/synthèse chimique , Fragments peptidiques/métabolisme , Fragments peptidiques/antagonistes et inhibiteurs , Mâle
9.
Inorg Chem ; 63(29): 13594-13601, 2024 Jul 22.
Article de Anglais | MEDLINE | ID: mdl-38973091

RÉSUMÉ

The development of low-cost and efficient photocatalysts to achieve water splitting to hydrogen (H2) is highly desirable but remains challenging. Herein, we design and synthesize two porous polymers (Co-Salen-P and Fe-Salen-P) by covalent bonding of salen metal complexes and pyrene chromophores for photocatalytic H2 evolution. The catalytic results demonstrate that the two polymers exhibit excellent catalytic performance for H2 generation in the absence of additional noble-metal photosensitizers and cocatalysts. Particularly, the H2 generation rate of Co-Salen-P reaches as high as 542.5 µmol g-1 h-1, which is not only 6 times higher than that of Fe-Salen-P but also higher than a large amount of reported Pt-assisted photocatalytic systems. Systematic studies show that Co-Salen-P displays faster charge separation and transfer efficiencies, thereby accounting for the significantly improved photocatalytic activity. This study provides a facile and efficient way to fabricate high-performance photocatalysts for H2 production.

10.
Sci Rep ; 14(1): 15175, 2024 07 02.
Article de Anglais | MEDLINE | ID: mdl-38956251

RÉSUMÉ

In the current study, we aimed to investigate whether disulfiram (DSF) exerts a neuroprotective role in cerebral ischemiareperfusion (CI-RI) injury by modulating ferredoxin 1 (FDX1) to regulate copper ion (Cu) levels and inhibiting inflammatory responses. To simulate CI-RI, a transient middle cerebral artery occlusion (tMCAO) model in C57/BL6 mice was employed. Mice were administered with or without DSF before and after tMCAO. Changes in infarct volume after tMCAO were observed using TTC staining. Nissl staining and hematoxylin-eosin (he) staining were used to observe the morphological changes of nerve cells at the microscopic level. The inhibitory effect of DSF on initial inflammation was verified by TUNEL assay, apoptosis-related protein detection and iron concentration detection. FDX1 is the main regulatory protein of copper death, and the occurrence of copper death will lead to the increase of HSP70 stress and inflammatory response. Cuproptosis-related proteins and downstream inflammatory factors were detected by western blotting, immunofluorescence staining, and immunohistochemistry. The content of copper ions was detected using a specific kit, while electron microscopy was employed to examine mitochondrial changes. We found that DSF reduced the cerebral infarction volume, regulated the expression of cuproptosis-related proteins, and modulated copper content through down regulation of FDX1 expression. Moreover, DSF inhibited the HSP70/TLR-4/NLRP3 signaling pathway. Collectively, DSF could regulate Cu homeostasis by inhibiting FDX1, acting on the HSP70/TLR4/NLRP3 pathway to alleviate CI/RI. Accordingly, DSF could mitigate inflammatory responses and safeguard mitochondrial integrity, yielding novel therapeutic targets and mechanisms for the clinical management of ischemia-reperfusion injury.


Sujet(s)
Cuivre , Disulfirame , Homéostasie , Inflammation , Souris de lignée C57BL , Lésion d'ischémie-reperfusion , Animaux , Lésion d'ischémie-reperfusion/métabolisme , Lésion d'ischémie-reperfusion/traitement médicamenteux , Lésion d'ischémie-reperfusion/anatomopathologie , Disulfirame/pharmacologie , Souris , Cuivre/métabolisme , Homéostasie/effets des médicaments et des substances chimiques , Mâle , Inflammation/métabolisme , Inflammation/traitement médicamenteux , Inflammation/anatomopathologie , Régulation négative/effets des médicaments et des substances chimiques , Infarctus du territoire de l'artère cérébrale moyenne/métabolisme , Infarctus du territoire de l'artère cérébrale moyenne/traitement médicamenteux , Modèles animaux de maladie humaine , Ferrosulfoprotéines/métabolisme , Encéphalopathie ischémique/métabolisme , Encéphalopathie ischémique/traitement médicamenteux , Encéphalopathie ischémique/anatomopathologie , Apoptose/effets des médicaments et des substances chimiques , Mitochondries/métabolisme , Mitochondries/effets des médicaments et des substances chimiques , Neuroprotecteurs/pharmacologie , Récepteur de type Toll-4/métabolisme
11.
J Imaging Inform Med ; 2024 Jul 08.
Article de Anglais | MEDLINE | ID: mdl-38977614

RÉSUMÉ

This study is to analyze and compare the diagnostic efficacy of the ADNEX model and O-RADS in Northeast China for benign and malignant ovarian-adnexal tumors. From July 2020 to February 2022, ultrasound images of 312 ovarian-adnexal masses included in the study were analyzed retrospectively, and the properties of these masses were identified using the ADNEX model and O-RADS. The diagnostic efficiency of the ADNEX model and O-RADS was analyzed using a ROC curve, and the capacities of the two models in differentiating benign and malignant ovarian masses at the optimum cutoff value were compared, as well as the consistency of their diagnosis results was evaluated. The study included 312 ovarian-adnexal masses, including 145 malignant masses and 167 benign masses from 287 patients with an average age of (46.8 ± 11.3) years. The AUC of the ADNEX model was 0.974, and the optimum cutoff value was the risk value > 24.2%, with the corresponding sensitivity and specificity being 97.93 and 86.83, respectively. The AUC of the O-RADS was 0.956, and the optimum cutoff value was > O-RADS 3, with the corresponding sensitivity and specificity being 97.24 and 85.03, respectively. The AUCs of the two models were 0.924 and 0.911 at the optimum cutoff values, with no statistical differences between them (P = 0.284). Consistency analysis: the kappa values of the two models for the determination and pathological results of masses were 0.840 and 0.815, respectively, and that for the diagnostic outcomes was 0.910. Both the ADNEX model and O-RADS had good diagnostic performance in people from Northeast China. Their diagnostic capabilities were similar, and diagnostic results were highly consistent at the optimum cutoff values.

12.
Chembiochem ; 25(16): e202400406, 2024 Aug 19.
Article de Anglais | MEDLINE | ID: mdl-38850275

RÉSUMÉ

The use of traditional Ag-based antibacterial agents is usually accompanied by uncontrollable silver release, which makes it difficult to find a balance between antibacterial performance and biosafety. Herein, we prepared a core-shell system of ZIF-8-derived amorphous carbon-coated Ag nanoparticles (Ag@C) as an ideal research model to reveal the synergistic effect and structure-activity relationship of the structural transformation of carbon shell and Ag core on the regulation of silver release behavior. It is found that Ag@C prepared at 600 °C (AC6) exhibits the best ion release kinetics due to the combination of relatively simple shell structure and lower crystallinity of the Ag core, thereby exerting stronger antibacterial properties (>99.999 %) at trace doses (20 µg mL-1) compared with most other Ag-based materials. Meanwhile, the carbon shell prevents the metal Ag from being directly exposed to the organism and thus endows AC6 with excellent biocompatibility. In animal experiments, AC6 can effectively promote wound healing by inactivating drug-resistant bacteria while regulating the expression of TNF-α and CD31. This work provides theoretical support for the scientific design and clinical application of controllable ion-releasing antibacterial agents.


Sujet(s)
Antibactériens , Nanoparticules métalliques , Tests de sensibilité microbienne , Argent , Argent/composition chimique , Argent/pharmacologie , Antibactériens/pharmacologie , Antibactériens/composition chimique , Animaux , Nanoparticules métalliques/composition chimique , Souris , Cicatrisation de plaie/effets des médicaments et des substances chimiques , Résistance bactérienne aux médicaments/effets des médicaments et des substances chimiques , Carbone/composition chimique , Carbone/pharmacologie , Infection de plaie/traitement médicamenteux , Infection de plaie/microbiologie , Infection de plaie/anatomopathologie , Libération de médicament , Humains , Staphylococcus aureus/effets des médicaments et des substances chimiques
13.
Medicine (Baltimore) ; 103(25): e38537, 2024 Jun 21.
Article de Anglais | MEDLINE | ID: mdl-38905411

RÉSUMÉ

The China mortality prediction model in trauma, based on the International Classification of Diseases, Tenth Revision, Clinical Modification lexicon (CMPMIT-ICD-10), is a novel model for predicting outcomes in patients who experienced trauma. This model has not yet been validated using data acquired from patients at other trauma centers in China. This retrospective study used data retrieved from the Peking University People's Hospital discharge database and included all patients admitted for trauma between 2012 and 2022 for model validation. Model performance was categorized into discrimination and calibration. In total, 23,299 patients were included in this study, with an overall mortality rate of 1.2%. CMPMIT-ICD-10 showed good discrimination and calibration, with an area under the curve of 0.84 (95% confidence interval: 0.82-0.87) and a Brier score of 0.02. The performance of the CMPMIT-ICD-10 during validation was satisfactory, and the application of the model will be scaled up in future studies.


Sujet(s)
Classification internationale des maladies , Plaies et blessures , Humains , Chine/épidémiologie , Mâle , Études rétrospectives , Femelle , Adulte d'âge moyen , Plaies et blessures/mortalité , Plaies et blessures/classification , Adulte , Sujet âgé , Centres de traumatologie/statistiques et données numériques
14.
Proc Natl Acad Sci U S A ; 121(20): e2318384121, 2024 May 14.
Article de Anglais | MEDLINE | ID: mdl-38713627

RÉSUMÉ

The reaction kinetics of photocatalytic CO2 reduction is highly dependent on the transfer rate of electrons and protons to the CO2 molecules adsorbed on catalytic centers. Studies on uncovering the proton effect in catalysts on photocatalytic activity of CO2 reduction are significant but rarely reported. In this paper, we, from the molecular level, revealed that the photocatalytic activity of CO2 reduction is closely related to the proton availability in catalysts. Specifically, four dinuclear Co(II) complexes based on Robson-type ligands with different number of carboxylic groups (-nCOOH; n = 0, 2, 4, 6) were designed and synthesized. All these complexes show photocatalytic activity for CO2 reduction to CO in a water-containing system upon visible-light illumination. Interestingly, the CO yields increase positively with the increase of the carboxylic-group number in dinuclear Co(II) complexes. The one containing -6COOH shows the best photocatalytic activity for CO2 reduction to CO, with the TON value reaching as high as 10,294. The value is 1.8, 3.4, and 7.8 times higher than those containing -4COOH, -2COOH, and -0COOH, respectively. The high TON value also makes the dinuclear Co(II) complex with -6COOH outstanding among reported homogeneous molecular catalysts for photocatalytic CO2 reduction. Control experiments and density functional theory calculation indicated that more carboxylic groups in the catalyst endow the catalyst with more proton relays, thus accelerating the proton transfer and boosting the photocatalytic CO2 reduction. This study, at a molecular level, elucidates that more carboxylic groups in catalysts are beneficial for boosting the reaction kinetics of photocatalytic CO2 reduction.

15.
Neuroscience ; 549: 121-137, 2024 Jun 21.
Article de Anglais | MEDLINE | ID: mdl-38754722

RÉSUMÉ

Myeloid differentiation primary response gene 88 (MyD88), a downstream molecule directly linked to Toll-like receptor (TLRs) and IL1 receptor, has been implicated in ischemia-reperfusion injury across various organs. However, its role in cerebral ischemia-reperfusion injury (CIRI) remains unclear. Five transient middle cerebral artery occlusion (tMCAO) microarray datasets were obtained from the Gene Expression Omnibus (GEO) database. We screened these datasets for differentially expressed genes (DEGs) using the GSE35338 and GSE58720 datasets and performed weighted gene co-expression network analysis (WGCNA) using the GSE30655, GSE28731, and GSE32529 datasets to identify the core module related to tMCAO. A protein-protein interaction (PPI) network was constructed using the intersecting DEGs and genes in the core module. Finally, we identified Myd88 was the core gene. In addition, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Set Enrichment Analysis (GSEA) validated that TNFα, IL17, and MyD88 signaling pathways were significantly enriched in tMCAO. Subsequently, we investigated the mechanistic role of MyD88 in the tMCAO model using male C57BL/6 mice. MyD88 expression increased significantly 24 h after reperfusion. After intraperitoneal administration of TJ-M2010-5, a MyD88-specific inhibitor, during reperfusion, the infarction volumes in the mice were ameliorated. TJ-M2010-5 inhibits the activation of microglia and astrocytes. Moreover, it attenuates the upregulation of inflammatory cytokines TNFα, IL17, and MMP9 while preserving the expression level of ZO1 after tMCAO, thereby safeguarding against blood-brain barrier (BBB) disruption. Finally, our findings suggest that MyD88 regulates the IRAK4/IRF5 signaling pathway associated with microglial activation. MyD88 participates in CIRI by regulating the inflammatory response and BBB damage following tMCAO.


Sujet(s)
Barrière hémato-encéphalique , Souris de lignée C57BL , Facteur de différenciation myéloïde-88 , Lésion d'ischémie-reperfusion , Facteur de différenciation myéloïde-88/métabolisme , Animaux , Lésion d'ischémie-reperfusion/métabolisme , Lésion d'ischémie-reperfusion/anatomopathologie , Barrière hémato-encéphalique/métabolisme , Barrière hémato-encéphalique/effets des médicaments et des substances chimiques , Barrière hémato-encéphalique/anatomopathologie , Mâle , Souris , Infarctus du territoire de l'artère cérébrale moyenne/métabolisme , Inflammation/métabolisme , Encéphalopathie ischémique/métabolisme , Encéphalopathie ischémique/anatomopathologie , Transduction du signal/effets des médicaments et des substances chimiques , Transduction du signal/physiologie , Microglie/métabolisme , Microglie/effets des médicaments et des substances chimiques , Cartes d'interactions protéiques , Pipérazines , Thiazoles
16.
Sci Rep ; 14(1): 5300, 2024 03 04.
Article de Anglais | MEDLINE | ID: mdl-38438409

RÉSUMÉ

Arterial occlusion-induced ischemic stroke (IS) is a highly frequent stroke subtype. Nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor that modulates antioxidant genes. Its role in IS is still unelucidated. The current study focused on constructing a transient middle cerebral artery occlusion (tMCAO) model for investigating the NRF2-related mechanism underlying cerebral ischemia/reperfusion (I/R) injury. Each male C57BL/6 mouse was injected with/with no specific NRF2 activator post-tMCAO. Changes in blood-brain barrier (BBB)-associated molecule levels were analyzed using western-blotting, PCR, immunohistochemistry, and immunofluorescence analysis. NRF2 levels within cerebral I/R model decreased at 24-h post-ischemia. NRF2 activation improved brain edema, infarct volume, and neurological deficits after MCAO/R. Similarly, sulforaphane (SFN) prevented the down-regulated tight junction proteins occludin and zonula occludens 1 (ZO-1) and reduced the up-regulated aquaporin 4 (AQP4) and matrix metalloproteinase 9 (MMP9) after tMCAO. Collectively, NRF2 exerted a critical effect on preserving BBB integrity modulating ferroptosis and inflammation. Because NRF2 is related to BBB injury regulation following cerebral I/R, this provides a potential therapeutic target and throws light on the underlying mechanism for clinically treating IS.


Sujet(s)
Ferroptose , Accident vasculaire cérébral ischémique , Lésion d'ischémie-reperfusion , Accident vasculaire cérébral , Animaux , Mâle , Souris , Barrière hémato-encéphalique , Infarctus cérébral , Inflammation , Ischémie , Souris de lignée C57BL , Facteur-2 apparenté à NF-E2 , Accident vasculaire cérébral/traitement médicamenteux
17.
Autoimmunity ; 57(1): 2332340, 2024 Dec.
Article de Anglais | MEDLINE | ID: mdl-38545756

RÉSUMÉ

Interferon-beta (IFN-ß) is one of the classical drugs for immunomodulatory therapy in relapsing-remitting multiple sclerosis (RRMS) patients, but the drug responsiveness of different patients varies. Currently, there is no valid model to predict IFN-ß responsiveness. This research attempted to develop an IFN-ß responsiveness prediction model based on mRNA expression in RRMS patient peripheral blood mononuclear cells. Peripheral blood mononuclear cell mRNA expression datasets including 50 RRMS patients receiving IFN-ß treatment were obtained from GEO. Among the datasets, 24 cases from GSE24427 were included in a training set, and 18 and 9 cases from GSE19285 and GSE33464, respectively, were adopted as two independent test sets. In the training set, blood samples were collected immediately before first, second, month 1, 12, and 24 IFN-ß injection, and the mRNA expression data at four time points, namely, two days, one month, one year and two years after the onset of IFN-ß treatment, were compared with pre-treatment data to identify IFN-stimulated genes (ISGs). The ISGs at the one-month time point were used to construct the drug responsiveness prediction model. Next, the drug responsiveness model was verified in the two independent test sets to examine the performance of the model in predicting drug responsiveness. Finally, we used CIBERSORTx to estimate the content of cell subtypes in samples and evaluated whether differences in the proportions of cell subtypes were related to differences in IFN-ß responsiveness. Among the four time points, one month was the time point when the training set GSE24427 and test set GSE33464 had the highest number of ISGs. Functional analysis showed that these one-month ISGs were enriched in biological functions such as the innate immune response, type-I interferon signalling pathway, and other IFN-ß-associated functions. Based on these ISGs, we obtained a four-factor prediction model for IFN-ß responsiveness including MX1, MX2, XAF1, and LAMP3. In addition, the model demonstrated favourable predictive performance within the training set and two external test sets. A higher proportion of activated NK cells and lower naive CD4/total CD4 ratio might indicate better drug responsiveness. This research developed a polygene-based biomarker model that could predict RRMS patient IFN-ß responsiveness in the early treatment period. This model could probably help doctors screen out patients who would not benefit from IFN-ß treatment early and determine whether a current treatment plan should be continued.


Sujet(s)
Sclérose en plaques récurrente-rémittente , Sclérose en plaques , Humains , ARN messager/génétique , Agranulocytes , Interféron bêta/usage thérapeutique , Interféron bêta/génétique , Sclérose en plaques récurrente-rémittente/diagnostic , Sclérose en plaques récurrente-rémittente/traitement médicamenteux , Sclérose en plaques récurrente-rémittente/génétique
18.
Chemistry ; 30(7): e202303345, 2024 Feb 01.
Article de Anglais | MEDLINE | ID: mdl-37964711

RÉSUMÉ

Homonuclear dual-atomic catalysts showcase unique electronic modulation due to their dual metal centres, providing new direction in development of efficient catalysts for CO2 electroreduction. This article highlights a few cutting-edge homonuclear dual-atomic catalysts, focusing on their inherent advantages in efficient and selective CO2 electroreduction, to spotlight the potential application of dual-atomic catalysts in CO2 electroreduction.

19.
Angew Chem Int Ed Engl ; 63(10): e202318735, 2024 Mar 04.
Article de Anglais | MEDLINE | ID: mdl-38108581

RÉSUMÉ

Covalent organic frameworks (COFs) have been widely studied in photocatalytic CO2 reduction reaction (CO2 RR). However, pristine COFs usually exhibit low catalytic efficiency owing to the fast recombination of photogenerated electrons and holes. In this study, we fabricated a stable COF-based composite (GO-COF-366-Co) by covalently anchoring COF-366-Co on the surface of graphene oxide (GO) for the photocatalytic CO2 reduction. Interestingly, in absolute acetonitrile (CH3 CN), GO-COF-366-Co shows a high selectivity of 94.4 % for the photoreduction of CO2 to formate, with a formate yield of 15.8 mmol/g, which is approximately four times higher than that using the pristine COF-366-Co. By contrast, in CH3 CN/H2 O (v : v=4 : 1), the main product for the photocatalytic CO2 reduction over GO-COF-366-Co is CO (96.1 %), with a CO yield as high as 52.2 mmol/g, which is also approximately four times higher than that using the pristine COF-366-Co. Photoelectrochemical experiments demonstrate the covalent bonding of COF-366-Co and GO to form the GO-COF-366-Co composite facilitates charge separation and transfer significantly, thereby accounting for the enhanced catalytic activity. In addition, theoretical calculations and in situ Fourier transform infrared spectroscopy reveal H2 O can stabilize the *COOH intermediate to further form a *CO intermediate via O-H(aq)⋅⋅⋅O(*COOH) hydrogen bonding, thus explaining the regulated photocatalytic performance.

20.
Adv Healthc Mater ; 12(32): e2302020, 2023 Dec.
Article de Anglais | MEDLINE | ID: mdl-37767984

RÉSUMÉ

Solid tumors are characterized by enhanced metabolism of lipid, particularly cholesterol, inspiring the exploration of metabolic therapy through cholesterol oxidase (COD)-mediated cholesterol deprivation. However, the therapeutic efficacy of COD is limited due to the hypoxic tumor microenvironment and the protective autophagy triggered by cholesterol deprivation. Herein, a combination therapy for metabolically treating solid tumors through COD in conjunction with molybdenum oxide nanodots (MONDs), which serve as both potent oxygen generators and autophagy inhibitors, is reported. MONDs convert H2 O2 (arising from COD-mediated cholesterol oxidation) into O2 , which is then recycled by COD to form reciprocal feedback for cholesterol depletion. Concurrently, MONDs can overcome autophagy-induced therapeutic resistance frequently occurring in conventional nutrient deprivation therapy by activating AKT/mTOR pathway phosphorylation. Combination therapy in the xenograft model results in an ≈5-fold increase in therapeutic efficiency as compared with COD treatment alone. This functionally cooperative metabolic coupling strategy holds great promise as a novel polytherapy approach that will benefit patients with solid tumors.


Sujet(s)
Autophagie , Tumeurs , Humains , Rétroaction , Tumeurs/traitement médicamenteux , Cholestérol , Phosphorylation , Lignée cellulaire tumorale , Microenvironnement tumoral
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