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1.
Small ; : e2400760, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566543

RESUMO

Industrial-level hydrogen production from the water electrolysis requires reducing the overpotential (η) as much as possible at high current density, which is closely related to intrinsic activity of the electrocatalysts. Herein, A-site cation deficiency engineering is proposed to screen high-performance catalysts, demonstrating effective Pr0.5- xLa0.5BaCo2O5+ δ (P0.5- xLBC) perovskites toward alkaline hydrogen evolution reaction (HER). Among all perovskite compositions, Pr0.4La0.5BaCo2O5+ δ (P0.4LBC) exhibits superior HER performance along with unique operating stability at large current densities (J = 500-2000 mA cm-2 geo). The overpotential of ≈636 mV is achieved in P0.4LBC at 2000 mA cm-2 geo, which outperforms commercial Pt/C benchmark (≈974 mV). Furthermore, the Tafel slope of P0.4LBC (34.1 mV dec-1) is close to that of Pt/C (35.6 mV dec-1), reflecting fast HER kinetics on the P0.4LBC catalyst. Combined with experimental and theoretical results, such catalytic activity may benefit from enhanced electrical conductivity, enlarged Co-O covalency, and decreased desorption energy of H* species. This results highlight effective A-site cation-deficient strategy for promoting electrochemical properties of perovskites, highlighting potential water electrolysis at ampere-level current density.

2.
Cell Insight ; 3(3): 100163, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38572176

RESUMO

Tuberculosis (TB) remains a prevalent global infectious disease caused by genetically closely related tubercle bacilli in Mycobacterium tuberculosis complex (MTBC). For a century, the Bacillus Calmette-Guérin (BCG) vaccine has been the primary preventive measure against TB. While it effectively protects against extrapulmonary forms of pediatric TB, it lacks consistent efficacy in providing protection against pulmonary TB in adults. Consequently, the exploration and development of novel TB vaccines, capable of providing broad protection to populations, have consistently constituted a prominent area of interest in medical research. This article presents a concise overview of the novel TB vaccines currently undergoing clinical trials, discussing their classification, protective efficacy, immunogenicity, advantages, and limitations. In vaccine development, the careful selection of antigens that can induce strong and diverse specific immune responses is essential. Therefore, we have summarized the molecular characteristics, biological function, immunogenicity, and relevant studies associated with the chosen antigens for TB vaccines. These insights gained from vaccines and immunogenic proteins will inform the development of novel mycobacterial vaccines, particularly mRNA vaccines, for effective TB control.

3.
J Mol Cell Biol ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578631

RESUMO

The recognition of cytosolic nucleic acid triggers the DNA/RNA sensor-IRF3 axis-mediated production of type I interferons (IFNs), which are essential for antiviral immune responses. However, the inappropriate activation of these signaling pathways is implicated in autoimmune conditions. Here, we report that indomethacin, a widely used nonsteroidal anti-inflammatory drug, inhibits nucleic acid-triggered IFN production. We found that both DNA- and RNA-stimulated IFN expression can be effectively blocked by indomethacin. Interestingly, indomethacin also prohibits the nuclear translocation of IRF3 following cytosolic nucleic acid recognition. Importantly, in cell lines and a mouse model of Aicardi-Goutières syndrome, indomethacin administration blunts self-DNA-induced autoimmune responses. Thus, our study reveals a previously unknown function of indomethacin and provides a potential treatment for cytosolic nucleic acid-stimulated autoimmunity.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38584973

RESUMO

Background: Bridging repair has emerged as a promising and reliable treatment strategy for the massive rotator cuff tears (MRCTs). However, there remains a lack of evidence on which bridging graft provides the better repair results, and a dearth of animal studies comparing bridging repairs with different grafts. The purpose of this study was to evaluate the histological and biomechanical outcomes of commonly used grafts (autologous fascia lata (FL), acellular dermal matrix graft (ADM), and polyethylene terephthalate (PET) patch). Methods: A total of 66 male New Zealand White Rabbits were used to mimic a model of unilateral chronic MRCTs. The rabbits were randomly divided into three groups: (1) FL group, which underwent bridging repair with autologous FL; (2) ADM group, which underwent bridging with ADM; and (3) PET group, which underwent bridging with PET patch. Tissue samples were collected and subjected to histological analysis using Hematoxylin and eosin, Picrosirius red, Safranin O/Fast green staining, and Immunostaining. Collagen diameter and fibril density in the regenerated tendon was analyzed with transmission electron microscopy (TEM). Additionally, biomechanical tests were performed at 6 and 12 weeks after repair. Results: The regenerated tendon successfully reattached to the footprint in all experimental groups. At 6 weeks after repair, the FL group had a significantly higher Modified Tendon Histological Evaluation (MTHE) score at the regenerated tendon than the PET group (13.2 ± 1.64 vs 9.6 ± 1.95, respectively; P = 0.038). The picrosirius red staining results showed that the FL group had a significantly higher type I collagen content than the ADM and PET groups at 6 weeks, and this difference was sustained with the PET group at 12 weeks (P < 0.05). Immunofluorescence analysis against CD68 indicated that the number of macrophage infiltrates was significantly lower in the FL group than in the ADM and PET groups (P < 0.05). At 12 weeks after repair, the area of Safranin O metachromasia was significant greater in ADM group than that in the PET group (P = 0.01). The FL group showed a significantly larger collagen diameter in the regenerated tendon than the PET group (P < 0.05), as indicated by TEM results. Furthermore, the FL group resulted in a greater failure load (at 6 weeks; 118.40 ± 16.70 N vs 93.75 ± 9.06 N, respectively; P = 0.019) and elastic modulus (at 6 weeks; 12.28 ± 1.94 MPa vs 9.58 ± 0.79 MPa, respectively; P = 0.024; at 12 weeks; 15.02 ± 2.36 MPa vs 11.63 ± 1.20 MPa, respectively; P = 0.032) than the ADM group. Conclusions: This study demonstrated that all three grafts could successfully bridging chronic MRCTs in a rabbit model. However, autologous FL promoted tendon regeneration and maturation, and enhanced the tensile properties of the tendon-to-bone complex when compared with ADM and PET grafts.

5.
Zhongguo Yi Liao Qi Xie Za Zhi ; 48(2): 179-183, 2024 Mar 30.
Artigo em Chinês | MEDLINE | ID: mdl-38605618

RESUMO

Objective: To introduce a locating device for the entry point of intramedullary nail based on the inertial navigation technology, which utilizes multi-dimensional angle information to assist in rapid and accurate positioning of the ideal direction of femoral anterograde intramedullary nails' entry point, and to verify its clinical value through clinical tests. Methods: After matching the locating module with the developing board, which are the two components of the locating device, they were placed on the skin surface of the proximal femur of the affected side. Anteroposterior fluoroscopy was performed. The developing angle corresponding to the ideal direction of entry point was selected based on the X-ray image, and then the yaw angle of the locating module was reset to zero. After resetting, the locating module was combined with the surgical instrument to guide the insertion angle of the guide wire. The ideal direction of entry point was accurately located based on the angle guidance. By setting up an experimental group and a control group for clinical surgical operations, the number of guide wire insertion times, surgical time, fluoroscopy frequency, and intraoperative blood loss with or without the locating device was recorded. Results: Compared to the control group, the experimental group showed significant improvement in the number of guide wire insertion times, surgical time, fluoroscopy frequency, and intraoperative blood loss, with a statistically significant difference (P<0.01). Conclusion: The locating device can assist doctors in quickly locating the entry point of intramedullary nail, effectively reducing the fluoroscopy frequency and surgical time by improving the success rate of the guide wire insertion with one shot, improving surgical efficiency, and possessing certain clinical value.


Assuntos
Fixação Intramedular de Fraturas , Cirurgia Assistida por Computador , Humanos , Pinos Ortopédicos , Perda Sanguínea Cirúrgica , Fluoroscopia/métodos , Fixação Intramedular de Fraturas/métodos , Cirurgia Assistida por Computador/métodos
6.
Nano Lett ; 24(15): 4408-4414, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38567928

RESUMO

Tuning the interfacial Schottky barrier with van der Waals (vdW) contacts is an important solution for two-dimensional (2D) electronics. Here we report that the interlayer dipoles of 2D vdW superlattices (vdWSLs) can be used to engineer vdW contacts to 2D semiconductors. A bipolar WSe2 with Ba6Ta11S28 (BTS) vdW contact was employed to exhibit this strategy. Strong interlayer dipoles can be formed due to charge transfer between the Ba3TaS5 and TaS2 layers. Mechanical exfoliation breaks the superlattice and produces two distinguished surfaces with TaS2 and Ba3TaS5 terminations. The surfaces thus have opposite surface dipoles and consequently different work functions. Therefore, all the devices fall into two categories in accordance with the rectifying direction, which were verified by electrical measurements and scanning photocurrent microscopy. The growing vdWSL family along with the addition surface dipoles enables prospective vdW contact designs and have practical application in nanoelectronics and nano optoelectronics.

7.
Anal Chim Acta ; 1302: 342516, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38580411

RESUMO

Conventional plate electrodes were commonly used in electrochemical flow injection analysis and only part of molecules diffused to the plane of electrodes could be detected, which would limit the performance of electrochemical detection. In this study, a low-cost native stainless steel wire mesh (SSWM) electrode was integrated into a 3D-printed device for electrochemical flow injection analysis with a pass-through mode, which is different compared with previous flow-through mode. This strategy was applied for sensitive analysis of hydrogen peroxide (H2O2) released from cells. Under the optimal conditions (the applied potentials, the flow rate and the sample volume), the device exhibits high sensitivity toward H2O2. Linear relationships could be achieved between electrochemical responses and the concentration of H2O2 ranging from 1 nM to 1 mM. The excellent analytical performance of the SSWM-based device could be attributed to the pass-through mode based on the mesh microstructure and intrinsic catalytic properties for H2O2 by stainless steel. This approach could be further successfully extended for screening of H2O2 released from HeLa cells with electrochemical responses linear to the number of cells in a range of 3 - 1.35 × 104 cells with an injection volume of 30 µL. This study revealed the potential of mesh electrodes in electrochemical flow injection analysis for cellular function and pathology and its possible extension in cell counting and on-line analysis.


Assuntos
Análise de Injeção de Fluxo , Peróxido de Hidrogênio , Humanos , Células HeLa , Peróxido de Hidrogênio/análise , Aço Inoxidável , Técnicas Eletroquímicas , Eletrodos
8.
Biomed Rep ; 20(5): 82, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38628627

RESUMO

Dihydromyricetin (DHM) is a natural flavonoid compound with multiple antitumour effects, including inhibition of proliferation, promotion of apoptosis, inhibition of invasion and migration, clearance of reactive oxygen species (ROS) and induction of autophagy. For example, DHM can effectively block the progression of the tumour cell cycle and inhibit cell proliferation. In different types of cancer cells, DHM can regulate the PI3K/Akt pathway, mTOR, and NF-κB pathway components, such as p53, and endoplasmic reticulum stress can alter the accumulation of ROS or induce autophagy to promote the apoptosis of tumour cells. In addition, when DHM is used in combination with various known chemotherapy drugs, such as paclitaxel, nedaplatin, doxorubicin, oxaliplatin and vinblastine, it can increase the sensitivity of tumour cells to DHM and increase the therapeutic effect of chemotherapy drugs. In the present review, the multiple molecular and cellular mechanisms underlying the antitumour effect of DHM, as well as its ability to increase the effects of various traditional antitumour drugs were summarized. Through the present review, it is expected by the authors to draw attention to the potential of DHM as an antitumour drug and provide valuable references for the clinical translation of DHM research and the development of related treatment strategies.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38657125

RESUMO

Cuprous thiocyanate (CuSCN) emerges as a prime candidate among inorganic hole-transport materials, particularly suitable for the fabrication of perovskite solar cells. Nonetheless, there is an Ohmic contact degradation between the perovskite and CuSCN layers. This is induced by polar solvents and undesired purities, which reduce device efficiency and operational stability. In this work, we introduce amidinothiourea (ASU) as an intermediate layer between perovskites and CuSCN to overcome the above obstacles. The characterization results confirm that ASU-modified perovskites have eliminated trap-induced defects by strong chemical bonding between -NH- and C═S from ASU and under-coordinated ions in perovskites. The interfacial engineering based on the ASU also reduces the potential barrier between the perovskite and CuSCN layers. The ASU-treated perovskite solar cells (PSC) with a gold electrode obtains an improved power conversion efficiency (PCE) from 16.36 to 18.03%. Furthermore, after being stored for 1800 h in ambient air (relative humidity (RH) = 45%), the related device without encapsulation maintains over 90% of its initial efficiency. The further combination of ASU and carbon-tape electrodes demonstrates its potential to fabricate low-cost but stable carbon-based PSCs. This work finds a universal approach for the fabrication of efficient and stable PSCs with different device structures.

10.
Nano Lett ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38647318

RESUMO

The discovery of room-temperature ferromagnetism in van der Waals (vdW) materials opens new avenues for exploring low-dimensional magnetism and its applications in spintronics. Recently, the observation of the room-temperature topological Hall effect in the vdW ferromagnet Fe3GaTe2 suggests the possible existence of room-temperature skyrmions, yet skyrmions have not been directly observed. In this study, real-space imaging was employed to investigate the domain evolution of the labyrinth and skyrmion structure. First, Néel-type skyrmions can be created at room temperature. In addition, the influence of flake thickness and external magnetic field (during field cooling) on both labyrinth domains and the skyrmion lattice is unveiled. Due to the competition between magnetic anisotropy and dipole interactions, the specimen thickness significantly influences the density of skyrmions. These findings demonstrate that Fe3GaTe2 can host room-temperature skyrmions of various sizes, opening up avenues for further study of magnetic topological textures at room temperature.

11.
BMJ ; 384: e078581, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443074

RESUMO

OBJECTIVE: To evaluate the diagnostic accuracy and safety of using magnetically guided capsule endoscopy with a detachable string (ds-MCE) for detecting and grading oesophagogastric varices in adults with cirrhosis. DESIGN: Prospective multicentre diagnostic accuracy study. SETTING: 14 medical centres in China. PARTICIPANTS: 607 adults (>18 years) with cirrhosis recruited between 7 January 2021 and 25 August 2022. Participants underwent ds-MCE (index test), followed by oesophagogastroduodenoscopy (OGD, reference test) within 48 hours. The participants were divided into development and validation cohorts in a ratio of 2:1. MAIN OUTCOME MEASURES: The primary outcomes were the sensitivity and specificity of ds-MCE in detecting oesophagogastric varices compared with OGD. Secondary outcomes included the sensitivity and specificity of ds-MCE for detecting high risk oesophageal varices and the diagnostic accuracy of ds-MCE for detecting high risk oesophagogastric varices, oesophageal varices, and gastric varices. RESULTS: ds-MCE and OGD examinations were completed in 582 (95.9%) of the 607 participants. Using OGD as the reference standard, ds-MCE had a sensitivity of 97.5% (95% confidence interval 95.5% to 98.7%) and specificity of 97.8% (94.4% to 99.1%) for detecting oesophagogastric varices (both P<0.001 compared with a prespecified 85% threshold). When using the optimal 18% threshold for luminal circumference of the oesophagus derived from the development cohort (n=393), the sensitivity and specificity of ds-MCE for detecting high risk oesophageal varices in the validation cohort (n=189) were 95.8% (89.7% to 98.4%) and 94.7% (88.2% to 97.7%), respectively. The diagnostic accuracy of ds-MCE for detecting high risk oesophagogastric varices, oesophageal varices, and gastric varices was 96.3% (92.6% to 98.2%), 96.9% (95.2% to 98.0%), and 96.7% (95.0% to 97.9%), respectively. Two serious adverse events occurred with OGD but none with ds-MCE. CONCLUSION: The findings of this study suggest that ds-MCE is a highly accurate and safe diagnostic tool for detecting and grading oesophagogastric varices and is a promising alternative to OGD for screening and surveillance of oesophagogastric varices in patients with cirrhosis. TRIAL REGISTRATION: ClinicalTrials.gov NCT03748563.


Assuntos
Endoscopia por Cápsula , Varizes Esofágicas e Gástricas , Varizes , Adulto , Humanos , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/etiologia , Cirrose Hepática/complicações , Estudos Prospectivos
12.
Research (Wash D C) ; 7: 0331, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38550779

RESUMO

The presence of endotoxemia is strongly linked to the development of endothelial dysfunction and disruption of myocardial microvascular reactivity. These factors play a crucial role in the progression of endotoxemic cardiomyopathy. Sepsis-related multiorgan damage involves the participation of the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs). However, whether DNA-PKcs contributes to endothelial dysfunction and myocardial microvascular dysfunction during endotoxemia remains unclear. Hence, we conducted experiments in mice subjected to lipopolysaccharide (LPS)-induced endotoxemic cardiomyopathy, as well as assays in primary mouse cardiac microvascular endothelial cells. Results showed that endothelial-cell-specific DNA-PKcs ablation markedly attenuated DNA damage, sustained microvessel perfusion, improved endothelial barrier function, inhibited capillary inflammation, restored endothelium-dependent vasodilation, and improved heart function under endotoxemic conditions. Furthermore, we show that upon LPS stress, DNA-PKcs recognizes a TQ motif in cofilin2 and consequently induces its phosphorylation at Thr25. Phosphorylated cofilin2 shows increased affinity for F-actin and promotes F-actin depolymerization, resulting into disruption of the endothelial barrier integrity, microvascular inflammation, and defective eNOS-dependent vasodilation. Accordingly, cofilin2-knockin mice expressing a phospho-defective (T25A) cofilin2 mutant protein showed improved endothelial integrity and myocardial microvascular function upon induction of endotoxemic cardiomyopathy. These findings highlight a novel mechanism whereby DNA-PKcs mediates cofilin2Thr25 phosphorylation and subsequent F-actin depolymerization to contribute to endotoxemia-related cardiac microvascular dysfunction.

13.
Biomed Pharmacother ; 174: 116456, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38552441

RESUMO

Acute lung injury (ALI) is a common and critical respiratory disorder caused by various factors, with viral infection being the leading contributor. Dehydroandrographolide (DAP), a constituent of the Chinese herbal plant Andrographis paniculata, exhibits a range of activities including anti-inflammatory, in vitro antiviral and immune-enhancing effects. This study evaluated the anti-inflammatory effects and pharmacokinetics (PK) profile of DAP in ALI mice induced by intratracheal instillation of Poly(I:C) (PIC). The results showed that oral administration of DAP (10-40 mg/kg) effectively suppressed the increase in lung wet-dry weight ratio, total cells, total protein content, accumulation of immune cells, inflammatory cytokines and neutrophil elastase levels in bronchoalveolar lavage fluid of PIC-treated mice. DAP concentrations, determined by an LC-MS/MS method, in plasma after receiving DAP (20 mg/kg) were unchanged compared to those in normal mice. However, DAP concentrations and relative PK parameters in the lungs were significantly altered in PIC-treated mice, exhibiting a relatively higher maximum concentration, larger AUC, and longer elimination half-life than those in the lungs of normal mice. These results demonstrated that DAP could improve lung edema and inflammation in ALI mice, and suggested that lung injury might influence the PK properties of DAP, leading to increased lung distribution and residence. Our study provides evidence that DAP displays significant anti-inflammatory activity against viral lung injury and is more likely to distribute to damaged lung tissue.

14.
Front Immunol ; 15: 1338096, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38495892

RESUMO

Type III interferon (IFN-λ), a new member of the IFN family, was initially considered to possess antiviral functions similar to those of type I interferon, both of which are induced via the JAK/STAT pathway. Nevertheless, recent findings demonstrated that IFN-λ exerts a nonredundant antiviral function at the mucosal surface, preferentially produced in epithelial cells in contrast to type I interferon, and its function cannot be replaced by type I interferon. This review summarizes recent studies showing that IFN-λ inhibits the spread of viruses from the cell surface to the body. Further studies have found that the role of IFN-λ is not only limited to the abovementioned functions, but it can also can exert direct and/or indirect effects on immune cells in virus-induced inflammation. This review focuses on the antiviral activity of IFN-λ in the mucosal epithelial cells and its action on immune cells and summarizes the pathways by which IFN-λ exerts its action and differentiates it from other interferons in terms of mechanism. Finally, we conclude that IFN-λ is a potent epidermal antiviral factor that enhances the respiratory mucosal immune response and has excellent therapeutic potential in combating respiratory viral infections.


Assuntos
Interferon Tipo I , Viroses , Humanos , Interferon lambda , Janus Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo , Interferon Tipo I/metabolismo , Epitélio/metabolismo , Antivirais/farmacologia , Antivirais/uso terapêutico
15.
ACS Cent Sci ; 10(2): 291-301, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38435525

RESUMO

The base excision repair glycosylase MUTYH prevents mutations associated with the oxidatively damaged base, 8-oxo-7,8-dihydroguanine (OG), by removing undamaged misincorporated adenines from OG:A mispairs. Defects in OG:A repair in individuals with inherited MUTYH variants are correlated with the colorectal cancer predisposition syndrome known as MUTYH-associated polyposis (MAP). Herein, we reveal key structural features of OG required for efficient repair by human MUTYH using structure-activity relationships (SAR). We developed a GFP-based plasmid reporter assay to define SAR with synthetically generated OG analogs in human cell lines. Cellular repair results were compared with kinetic parameters measured by adenine glycosylase assays in vitro. Our results show substrates lacking the 2-amino group of OG, such as 8OI:A (8OI = 8-oxoinosine), are not repaired in cells, despite being excellent substrates in in vitro adenine glycosylase assays, new evidence that the search and detection steps are critical factors in cellular MUTYH repair functionality. Surprisingly, modification of the O8/N7H of OG, which is the distinguishing feature of OG relative to G, was tolerated in both MUTYH-mediated cellular repair and in vitro adenine glycosylase activity. The lack of sensitivity to alterations at the O8/N7H in the SAR of MUTYH substrates is distinct from previous work with bacterial MutY, indicating that the human enzyme is much less stringent in its lesion verification. Our results imply that the human protein relies almost exclusively on detection of the unique major groove position of the 2-amino group of OG within OGsyn:Aanti mispairs to select contextually incorrect adenines for excision and thereby thwart mutagenesis. These results predict that MUTYH variants that exhibit deficiencies in OG:A detection will be severely compromised in a cellular setting. Moreover, the reliance of MUTYH on the interaction with the OG 2-amino group suggests that disrupting this interaction with small molecules may provide a strategy to develop potent and selective MUTYH inhibitors.

16.
Heliyon ; 10(5): e27159, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38468952

RESUMO

Colorectal cancer (CRC) is one of the most common cancers and the second most deadly cancer across the globe. Colorectal cancer stem cells (CCSCs) fuel CRC growth, metastasis, relapse, and chemoresistance. A complete understanding of the modulatory mechanisms of CCSC biology is essential for developing efficacious CRC treatment. In the current study, we characterized the expression and function of GTP binding protein 2 (GTPBP2) in a chemical-induced mouse CRC model. We found that GTPBP2 was expressed at a higher level in CD133+CD44+ CCSCs compared with other CRC cells. Using a lentivirus-based Cas9/sgRNA system, GTPBP2 expression was ablated in CRC cells in vitro. GTPBP2 deficiency caused the following effects on CCSCs: 1) Significantly accelerating proliferation and increasing the proportions of cells at G1, S, and G2/M phase; 2) Impairing resistance to 5-Fluorouracil; 3) Weakening self-renewal but not impacting cell migration. In addition, GTPBP2 deficiency remarkably decreased ß-catenin expression while increasing ß-catenin phosphorylation in CCSCs. These effects of GTPBP2 were present in CCSCs but not in other CRC cell populations. The Wnt agonist SKL2001 completely abolished these changes in GTPBP2-deficient CCSCs. When GTPBP2-deficient CCSCs were implanted in nude mice, they exhibited consistent changes compared with GTPBP2-expressing CCSCs. Collectively, this study indicates that GTPBP2 positively modulates Wnt signaling to reinforce the quiescence, self-renewal, and chemoresistance of mouse CCSCs. Therefore, we disclose a novel mechanism underlying CCSC biology and GTPBP2 could be a therapeutic target in future CRC treatment.

17.
Biochem Pharmacol ; 223: 116138, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38494062

RESUMO

Central nervous system lymphoma (CNSL) is a type of hematological tumor. Treatment of CNSL is difficult due to the existence of the blood-brain barrier (BBB). Here, we used exosomes (Exos), a type of extracellular vesicle, and iRGD to construct a new drug carrier system and use it to load doxorubicin (DOX). The results of in vitro and in vivo experiments showed that the iRGD-Exo-DOX system can efficiently and securely transport DOX through the BBB and target tumor cells. The results suggest that iRGD-Exo-DOX may cross the BBB through brain microvascular endothelial cell-mediated endocytosis. Together, our study indicates an impactful treatment of central nervous system tumors.


Assuntos
Neoplasias do Sistema Nervoso Central , Linfoma , Humanos , Barreira Hematoencefálica , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Linfoma/tratamento farmacológico , Linhagem Celular Tumoral
18.
Int J Med Sci ; 21(4): 755-764, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464835

RESUMO

Alcoholic liver disease (ALD) poses a substantial global health challenge, with its pathogenesis deeply rooted in mitochondrial dysfunction. Our study explores the pivotal roles of Phosphoglycerate mutase family member 5 (Pgam5) and Voltage-Dependent Anion Channel 1 (VDAC1) in the progression of ALD, providing novel insights into their interplay and impact on mitochondrial integrity. We demonstrate that Pgam5 silencing preserves hepatocyte viability and attenuates ethanol-induced apoptosis, underscoring its detrimental role in exacerbating hepatocyte dysfunction. Pgam5's influence extends to the regulation of VDAC1 oligomerization, a key process in mitochondrial permeability transition pore (mPTP) opening, mitochondrial swelling, and apoptosis initiation. Notably, the inhibition of VDAC1 oligomerization through Pgam5 silencing or pharmacological intervention (VBIT-12) significantly preserves mitochondrial function, evident in the maintenance of mitochondrial membrane potential and reduced reactive oxygen species (ROS) production. In vivo experiments using hepatocyte-specific Pgam5 knockout (Pgam5hKO) and control mice reveal that Pgam5 deficiency mitigates ethanol-induced liver histopathology, inflammation, lipid peroxidation, and metabolic disorder, further supporting its role in ALD progression. Our findings highlight the critical involvement of Pgam5 and VDAC1 in mitochondrial dysfunction in ALD, suggesting potential therapeutic targets. While promising, these findings necessitate further research, including human studies, to validate their clinical applicability and explore broader implications in liver diseases. Overall, our study provides a significant advancement in understanding ALD pathophysiology, paving the way for novel therapeutic strategies targeting mitochondrial pathways in ALD.


Assuntos
Hepatopatias Alcoólicas , Doenças Mitocondriais , Animais , Humanos , Camundongos , Etanol/toxicidade , Etanol/metabolismo , Hepatopatias Alcoólicas/genética , Mitocôndrias/genética , Mitocôndrias/metabolismo , Fosfoglicerato Mutase/genética , Fosfoglicerato Mutase/metabolismo , Canal de Ânion 1 Dependente de Voltagem/genética , Canal de Ânion 1 Dependente de Voltagem/metabolismo
19.
J Nanobiotechnology ; 22(1): 103, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468261

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) is a prevalent inflammatory autoimmune disease characterised by persistent inflammation and joint damage with elevated levels of reactive oxygen species (ROS). Current treatment modalities for RA have significant limitations, including poor bioavailability, severe side effects, and inadequate targeting of inflamed joints. Herein, we synthesised cerium/manganese oxide nanoparticles (NPs) as efficient drug carriers with antioxidant and catalytic-like functions that can eliminate ROS to facilitate the polarization of macrophages phenotype from M1 to M2 and alleviate inflammation. Methotrexate (MTX), a first-line RA medication, was loaded into the NPs, which were further modified with bovine serum albumin (BSA) and integrated into dissolving hyaluronic acid-based microneedles (MNs) for transdermal delivery. RESULT: This innovative approach significantly enhanced drug delivery efficiency, reduced RA inflammation, and successfully modulated macrophage polarization toward an anti-inflammatory phenotype. CONCLUSION: This research not only presents a promising drug delivery strategy for RA but also contributes broadly to the field of immune disease treatment by offering an advanced approach for macrophage phenotypic reprogramming.


Assuntos
Artrite Reumatoide , Cério , Compostos de Manganês , Nanopartículas , Óxidos , Humanos , Manganês/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Artrite Reumatoide/tratamento farmacológico , Macrófagos , Inflamação , Cério/farmacologia
20.
Blood Adv ; 2024 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-38457926

RESUMO

Multiple myeloma (MM) cells are addicted to MYC and its direct transactivation target IRF4 for proliferation and survival. MYC and IRF4 are still considered "undruggable" as the majority of small molecule inhibitors suffers from low potency, suboptimal pharmacokinetic properties and undesirable off-target effects. Indirect inhibition of MYC/IRF4 emerges as a therapeutic vulnerability in MM. Here, we uncover an unappreciated tumor suppressive role of C-terminal Binding Protein 2 (CTBP2) in MM via strong inhibition of the MYC-IRF4 axis. In contrast to epithelial cancers, CTBP2 is frequently downregulated in MM, in association with shortened survival, hyperproliferative features and adverse clinical outcomes. Restoration of CTBP2 exhibited potent anti-tumor effects against MM in vitro and in vivo, with marked repression of MYC-IRF4 network genes. Mechanistically, CTBP2 impeded transcription of MYC and IRF4 by histone H3 lysine 27 deacetylation (H3K27ac), and indirectly via activation of MYC repressor IFIT3. In addition, activation of interferon gene signature by CTBP2 suggested its concomitant immunomodulatory role in MM. Epigenetic studies revealed contribution of polycomb-mediated silencing and DNA methylation to CTBP2 inactivation in MM. Notably, inhibitors of Enhance of zeste homolog 2 (EZH2), histone deacetylase (HDACs) and DNA methyltransferase (DNMTs) currently under evaluation in clinical trials were effective in restoring CTBP2 expression in MM. Our findings indicated that loss of CTBP2 plays an essential role in myelomagenesis and decipher an additional mechanistic link on MYC-IRF4 dysregulation in MM. We envision that identification of novel critical regulators would facilitate the development of selective and effective approaches for treating this MYC/IRF4-addicted malignancy.

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