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1.
Mol Pharmacol ; 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38769019

RESUMEN

Remdesivir (RDV), a broad-spectrum antiviral agent, is often used together with dexamethasone (DEX) for hospitalized COVID­19 patients requiring respiratory support. Potential hepatic adverse drug reaction is a safety concern associated with the use of RDV. We previously reported that DEX co-treatment effectively mitigates RDV-induced hepatotoxicity and reduces elevated serum ALT and AST levels in cultured human primary hepatocytes (HPH) and hospitalized COVID-19 patients, respectively. Yet, the precise mechanism behind this protective drug-drug interaction remains largely unknown. We show here that through the activation of p38, c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinases 1 and 2 (ERK1/2) signaling, RDV induces apoptosis (cleavage of caspases 8, 9, and 3), autophagy (increased autophagosome and LC3-II), and mitochondrial damages (decreased membrane potential, respiration, ATP levels, and increased expression of Bax and the released cytosolic cytochrome C) in HPH. Importantly, co-treatment with DEX partially reversed RDV-induced apoptosis, autophagy, and cell death. Mechanistically, DEX deactivates/dephosphorylates p38, JNK, and ERK1/2 signaling by enhancing the expression of dual specificity protein phosphatase 1 (DUSP1), a mitogen-activated protein kinase (MAPK) phosphatase, in a glucocorticoid receptor (GR)-dependent manner. Knockdown of GR in HPH attenuates DEX-mediated DUSP1 induction, MAPK dephosphorylation, as well as protection against RDV-induced hepatotoxicity. Collectively, our findings suggest a molecular mechanism by which DEX modulates the GR-DUSP1-MAPK regulatory axis to alleviate the adverse actions of RDV in the liver. Significance Statement The research uncovers the molecular mechanisms by which dexamethasone safeguards against remdesivir-associated liver damage in the context of COVID-19 treatment.

2.
Opt Lett ; 49(8): 2053-2056, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38621074

RESUMEN

Plasmonic nanosensors and the dynamic control of light fields are of the utmost significance in the field of micro- and nano-optics. Here, our study successfully demonstrates a plasmonic nanosensor in a compact coupled resonator system and obtains the pressure-induced transparency phenomenon for the first time to our knowledge. The proposed structure consists of a groove and slot cavity coupled in the metal-insulator-metal waveguide, whose mechanical and optical characteristics are investigated in detail using the finite element method. Simulation results show that we construct a quantitative relationship among the resonator deformation quantity, the applied pressure variation, and the resonant wavelength offset by combining the mechanical and optical properties of the proposed system. The physical features contribute to highly efficient plasmonic nanosensors for refractive index and optical pressure sensing with sensitivity of 1800 nm/RIU and 7.4 nm/MPa, respectively. Furthermore, the light waves are coupled to each other in the resonators, which are detuned due to the presence of pressure, resulting in the pressure-induced transparency phenomenon. It is noteworthy to emphasize that, unlike previously published works, our numerical results take structural deformation-induced changes in optical properties into account, making them trustworthy and practical. The proposed structure introduces a novel, to the best of our knowledge, approach for the dynamic control of light fields and has special properties that can be utilized for the realization of various integrated components.

3.
Biochem Biophys Res Commun ; 711: 149911, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38603832

RESUMEN

Macrophages play a crucial role in host response and wound healing, with M2 polarization contributing to the reduction of foreign-body reactions induced by the implantation of biomaterials and promoting tissue regeneration. Electrical stimulation (ES) and micropatterned substrates have a significant impact on the macrophage polarization. However, there is currently a lack of well-established cell culture platforms for studying the synergistic effects of these two factors. In this study, we prepared a graphene free-standing substrate with 20 µm microgrooves using capillary forces induced by water evaporation. Subsequently, we established an ES cell culture platform for macrophage cultivation by integrating a self-designed multi-well chamber cell culture device. We observed that graphene microgrooves, in combination with ES, significantly reduce cell spreading area and circularity. Results from immunofluorescence, ELISA, and flow cytometry demonstrate that the synergistic effect of graphene microgrooves and ES effectively promotes macrophage M2 phenotypic polarization. Finally, RNA sequencing results reveal that the synergistic effects of ES and graphene microgrooves inhibit the macrophage actin polymerization and the downstream PI3K signaling pathway, thereby influencing the phenotypic transition. Our results demonstrate the potential of graphene-based microgrooves and ES to synergistically modulate macrophage polarization, offering promising applications in regenerative medicine.


Asunto(s)
Estimulación Eléctrica , Grafito , Macrófagos , Grafito/química , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Animales , Ratones , Células RAW 264.7 , Polaridad Celular/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal
4.
Nat Commun ; 15(1): 2563, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38519460

RESUMEN

Numerous studies have demonstrated the correlation between human gut bacteria and host physiology, mediated primarily via nuclear receptors (NRs). Despite this body of work, the systematic identification and characterization of microbe-derived ligands that regulate NRs remain a considerable challenge. In this study, we discover a series of diindole molecules produced from commensal bacteria metabolites that act as specific agonists for the orphan constitutive androstane receptor (CAR). Using various biophysical analyses we show that their nanomolar affinities are comparable to those of synthetic CAR agonists, and that they can activate both rodent and human CAR orthologues, which established synthetic agonists cannot. We also find that the diindoles, diindolylmethane (DIM) and diindolylethane (DIE) selectively up-regulate bona fide CAR target genes in primary human hepatocytes and mouse liver without causing significant side effects. These findings provide new insights into the complex interplay between the gut microbiome and host physiology, as well as new tools for disease treatment.


Asunto(s)
Receptor de Androstano Constitutivo , Microbiota , Ratones , Animales , Humanos , Receptores Citoplasmáticos y Nucleares/metabolismo , Hepatocitos/metabolismo , Ligandos
5.
Microbiol Res ; 282: 127659, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38430890

RESUMEN

The presence of a multibasic cleavage site in the Spike protein of SARS-CoV-2 makes it prone to be cleaved by Furin at the S1/S2 junction (aa. 685-686), which enhances the usage of TMPRSS2 to promote cell-cell fusion to form syncytia. Syncytia may contribute to pathology by facilitating viral dissemination, cytopathicity, immune evasion, and inflammation. However, the role of other SARS-CoV-2 encoding viral proteins in syncytia formation remains largely unknown. Here, we report that SARS-CoV-2 M protein effectively inhibits syncytia formation triggered by Spike or its variants (Alpha, Delta, Omicron, etc.) and prevents Spike cleavage into S1 and S2 based on a screen assay of 20 viral proteins. Mechanistically, M protein interacts with Furin and inhibits its enzymatic activity, preventing the cleavage of Spike. In addition, M interacts with Spike independent of its cytoplasmic tail, retaining it within the cytoplasm and reducing cell membrane localization. Our findings offer new insights into M protein's role in regulating Spike's function and underscore the importance of functional interplay among viral proteins, highlighting potential avenues for SARS-CoV-2 therapy development.


Asunto(s)
COVID-19 , Furina , Humanos , SARS-CoV-2 , Membrana Celular , Proteínas de la Membrana , Glicoproteína de la Espiga del Coronavirus
6.
Clocks Sleep ; 6(1): 183-199, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38534801

RESUMEN

Previous work has demonstrated the modest impact of environmental interventions that manipulate lighting, sound, or temperature on sleep inertia symptoms. The current study sought to expand on previous work and measure the impact of a multimodal intervention that collectively manipulated light, sound, and ambient temperature on sleep inertia. Participants slept in the lab for four nights and were awoken each morning by either a traditional alarm clock or the multimodal intervention. Feelings of sleep inertia were measured each morning through Psychomotor Vigilance Test (PVT) assessments and ratings of sleepiness and mood at five time-points. While there was little overall impact of the intervention, the participant's chronotype and the length of the lighting exposure on intervention mornings both influenced sleep inertia symptoms. Moderate evening types who received a shorter lighting exposure (≤15 min) demonstrated more lapses relative to the control condition, whereas intermediate types exhibited a better response speed and fewer lapses. Conversely, moderate evening types who experienced a longer light exposure (>15 min) during the intervention exhibited fewer false alarms over time. The results suggest that the length of the environmental intervention may play a role in mitigating feelings of sleep inertia, particularly for groups who might exhibit stronger feelings of sleep inertia, including evening types.

7.
Methods Mol Biol ; 2749: 85-90, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38133776

RESUMEN

Accurate evaluation of potential drug risks such as drug-induced liver injury (DILI) continues to be a challenge faced by pharmaceutical industry and regulatory agencies. Preclinical testing has served as a foundation for the evaluation of the potential risks and effectiveness of investigational new drug (IND) products in humans. However, current two-dimensional (2D) in vitro human primary hepatocyte (HPH) culture systems cannot accurately depict and simulate the rich environment and complex processes observed in vivo, while animal studies present inherited species-specific differences and low throughput scales. Thus, there is a continued demand to establish new approaches that can better characterize DILI during drug discovery and development. Among others, the three-dimensional (3D) hepatic spheroid model comprising self-aggregated primary human hepatocytes cocultured with non-parenchymal cells (NPCs) appears to be a more accurate representation of the natural hepatic microenvironment with intercellular interactions between hepatocytes, stellate cells, Kupffer cells, liver sinusoidal endothelial cells (LSECs), and other cell types. This model holds the potential to improve the ability for long-term functional and toxicological studies. Here, we provide methodological details for this human hepatic spheroid coculture model system.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Células Endoteliales , Animales , Humanos , Técnicas de Cocultivo , Células Endoteliales/metabolismo , Hígado , Hepatocitos/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo
8.
Opt Express ; 31(22): 35697-35708, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-38017735

RESUMEN

Electromagnetically induced absorption (EIA) exhibits abnormal dispersion and novel fast-light features, making it a crucial aspect of nanophotonics. Here, the EIA phenomenon is numerically predicted in a compact plasmonic waveguide system by introducing a slot resonator above a square cavity. Simulation results reveal that the EIA response can be easily tuned by altering the structure's parameters, and double EIA valleys can be observed with an additional slot resonator. Furthermore, the investigated structures demonstrate a fast-light effect with an optical delay of ∼ -1.0 ps as a result of aberrant dispersion at the EIA valley, which enable promising applications in the on-chip fast-light area. Finally, a plasmonic nanosensor with a sensitivity of ∼1200 nm/RIU and figure of merit of ∼16600 is achieved based on Fano resonance. The special features of our suggested structure are applicable in realization of various integrated components for the development of multifunctional high-performance nano-photonic devices.

9.
Macromol Biosci ; 23(11): e2300190, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37483061

RESUMEN

Hollow polymer microcapsules as drug carriers have the advantages of drug protection, storage, and controlled release. Microcapsules combined with tissue engineering scaffolds such as electrospun microfibers can enhance long-term local drug retention. However, the combination methods of microcapsules and fibers still need to be further explored. Here, different technical approaches to functionalize electrospun polycaprolactone (PCL) microfibers with silk fibroin (SF) microcapsules through encapsulation and surface immobilization are developed, including direct blending and emulsion electrospinning for encapsulation, as well as covalent and cleavable disulfide-linkage for surface immobilization. The results of "blending" approach show that silk microcapsules with different sizes could be uniformly encapsulated inside electrospun fibers without aggregation. To further reduce the use of organic solvents, the microcapsules in the aqueous phase can be uniformly distributed in the PCL organic phase and successfully electrospun into fibers using surfactant span-80. For surface immobilization, silk microcapsules are efficiently covalent binding to the surface of electrospun PCL fibers via click chemistry and exhibited noncytotoxic. Based on this method, with the incorporation of a disulfide bond, the linkages between microcapsule and fiber could be cleaved under reducing conditions. These microcapsule-electrospun fiber combination methods provide sufficient options for different drug delivery requirements.


Asunto(s)
Fibroínas , Seda , Seda/química , Cápsulas , Andamios del Tejido/química , Fibroínas/química , Disulfuros
10.
ACS Appl Mater Interfaces ; 15(31): 37775-37783, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37467111

RESUMEN

Electrical conductivity, cell-guided surface topology, and drug storage capacity of biomaterials are attractive properties for the repair and regeneration of anisotropic tissues with electrical sensitivity, such as nerves. However, designing and fabricating implantable biomaterials with all these functions remain challenging. Herein, we developed a freestanding graphene substrate with micropatterned surfaces by a simple templating method. Importantly, the raised surface micropatterns had an internal hollow structure. The morphology results showed that the template microgroove width and the graphene nanosheet size were important indicators of the formation of the hollow structures. Through real-time monitoring and theoretical analysis of the formation process, it was found that the main formation mechanism was the delamination and interlayer movement of the graphene nanosheets triggered by the evaporation-induced capillary force. Finally, we achieved the controlled release of loaded microparticles and promoted the orientation of rat dorsal root ganglion neurons by applying an electric field to the hollow micropatterns. This capillarity-induced self-assembly strategy paves the way for the development of high-performance graphene micropatterned films with a hollow structure that have potential for clinical application in the repair of nerve injury.


Asunto(s)
Grafito , Ratas , Animales , Grafito/química , Acción Capilar , Almacenaje de Medicamentos , Neuronas , Materiales Biocompatibles
11.
Adv Healthc Mater ; 12(26): e2300885, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37256720

RESUMEN

In the surgical treatment of urinary diseases, ureteral stents are commonly used interventional medical devices. Although polymer ureteral stents with polyurethane as the main constituent are widely used in the clinic, the need for secondary surgery to remove them and their propensity to cause bacterial infections greatly limit their effectiveness. To satisfy clinical requirements, an electrospinning-based strategy to fabricate PLGA ureteral stents with silver@graphdiyne is innovated. Silver (Ag) nanoparticles are uniformly loaded on the surface of graphdiyne (GDY) flakes. It is found that the incorporation of Ag nanoparticles into GDY markedly increases their antibacterial properties. Subsequently, the synthesized and purified Ag@GDY is homogeneously blended with poly(lactic-co-glycolic acid) (PLGA) as an antimicrobial agent, and electrospinning along with high-speed collectors is used to make tubular stents. The antibacterial effect of Ag@GDY and the porous microstructure of the stents can effectively prevent bacterial biofilm formation. Furthermore, the stents gradually decrease in toughness but increase in strength during the degradation process. The cellular and subcutaneous implantation experiments demonstrate the moderate biocompatibility of the stents. In summary, considering these performance characteristics and the technical feasibility of the approach taken, this study opens new possibilities for the design and application of biodegradable ureteral stents.


Asunto(s)
Antiinfecciosos , Nanopartículas del Metal , Nanocompuestos , Plata/farmacología , Stents/microbiología , Antibacterianos/farmacología , Antibacterianos/química
12.
Opt Lett ; 48(7): 1754-1757, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37221758

RESUMEN

Imaging through scattering media is a fascinating subject in the computational imaging domain. The methods based on speckle correlation imaging have found tremendous versatility. However, a darkroom condition without any stray light is required because the speckle contrast is easily disturbed by ambient light, which can lead to the reduction in object reconstruction quality. Here, we report a plug-and-play (PnP) algorithm to restore the object through scattering media under the non-darkroom environment. Specifically, the PnPGAP-FPR method is established via the generalized alternating projection (GAP) optimization framework, Fienup phase retrieval (FPR) method, and FFDNeT. The proposed algorithm is demonstrated experimentally and shows significant effectiveness and flexible scalability, which describe the potential for its practical applications.

13.
Artículo en Inglés | MEDLINE | ID: mdl-37021899

RESUMEN

Training noise-robust deep neural networks (DNNs) in label noise scenario is a crucial task. In this paper, we first demonstrates that the DNNs learning with label noise exhibits over-fitting issue on noisy labels because of the DNNs is too confidence in its learning capacity. More significantly, however, it also potentially suffers from under-learning on samples with clean labels. DNNs essentially should pay more attention on the clean samples rather than the noisy samples. Inspired by the sample-weighting strategy, we propose a meta-probability weighting (MPW) algorithm which weights the output probability of DNNs to prevent DNNs from over-fitting to label noise and alleviate the under-learning issue on the clean sample. MPW conducts an approximation optimization to adaptively learn the probability weights from data under the supervision of a small clean dataset, and achieves iterative optimization between probability weights and network parameters via meta-learning paradigm. The ablation studies substantiate the effectiveness of MPW to prevent the deep neural networks from overfitting to label noise and improve the learning capacity on clean samples. Furthermore, MPW achieves competitive performance with other state-of-the-art methods on both synthetic and real-world noises.

14.
ACS Appl Mater Interfaces ; 15(16): 20228-20239, 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37052205

RESUMEN

Aqueous cold sintering of two lithium-based compounds, the electrolyte Li6.25La3Zr2Al0.25O12 (LLZAO) and cathode material LiCoO2 (LCO), is reported. For LLZAO, a relative density of ∼87% was achieved, whereas LCO was sintered to ∼95% with 20 wt % LLZAO as a flux/binder. As-cold sintered LLZAO exhibited a low total conductivity (10-8 S/cm) attributed to an insulating grain boundary blocking layer of Li2CO3. The blocking layer was reduced with a post-annealing process or, more effectively, by replacing deionized water with 5 M LiCl during cold sintering to achieve a total conductivity of ∼3 × 10-5 S/cm (similar to the bulk conductivity). For LCO-LLZAO composites, scanning electron microscopy and X-ray computer tomography indicated a continuous LCO matrix with the LLZAO phase evenly distributed but isolated throughout the ceramics. [001] texturing during cold sintering resulted in an order of magnitude difference in electronic conductivity between directions perpendicular and parallel to the c-axis at room temperature. The electronic conductivity (∼10-2 S/cm) of cold sintered LCO-LLZAO ceramics at room temperature was comparable to that of single crystals and higher than those synthesized via either conventional sintering or hot pressing.

15.
Hepatol Commun ; 7(3): e0034, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36809346

RESUMEN

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a global pandemic that has caused more than 600 million cases and over six million deaths worldwide. Despite the availability of vaccination, COVID-19 cases continue to grow making pharmacological interventions essential. Remdesivir (RDV) is an FDA-approved antiviral drug for treatment of both hospitalized and non-hospitalized COVID-19 patients, albeit with potential for hepatotoxicity. This study characterizes the hepatotoxicity of RDV and its interaction with dexamethasone (DEX), a corticosteroid often co-administered with RDV for inpatient treatment of COVID-19. METHODS: Human primary hepatocytes and HepG2 cells were used as in vitro models for toxicity and drug-drug interaction studies. Real-world data from hospitalized COVID-19 patients were analyzed for drug-induced elevation of serum ALT and AST. RESULTS: In cultured hepatocytes, RDV markedly reduced the hepatocyte viability and albumin synthesis, while it increased the cleavage of caspase-8 and caspase-3, phosphorylation of histone H2AX, and release of ALT and AST in a concentration-dependent manner. Importantly, co-treatment with DEX partially reversed RDV-induced cytotoxic responses in human hepatocytes. Moreover, data from COVID-19 patients treated with RDV with and without DEX co-treatment suggested that among 1037 patients matched by propensity score, receiving the drug combination was less likely to result in elevation of serum AST and ALT levels (≥ 3 × ULN) compared to the RDV alone treated patients (OR = 0.44, 95% CI = 0.22-0.92, p = 0.03). CONCLUSION: Our findings obtained from in vitro cell-based experiments and patient data analysis provide evidence suggesting combination of DEX and RDV holds the potential to reduce the likelihood of RDV-induced liver injury in hospitalized COVID-19 patients.


Asunto(s)
COVID-19 , Enfermedad Hepática Inducida por Sustancias y Drogas , Humanos , Tratamiento Farmacológico de COVID-19 , Hepatocitos , Dexametasona
16.
Opt Lett ; 48(2): 287-290, 2023 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-36638439

RESUMEN

Imaging dynamic strongly scattering scenes remains a significant challenge because it is typically believed that moving objects and dynamic media provide huge barriers. Instead, we use the dynamics of objects and media and put forward a recursion-driven bispectral imaging (ReDBI) framework here for the reconstruction of a stationary or moving object hidden behind the dynamic media. ReDBI avoids the errors introduced by speckle modulation and phase-retrieval algorithms in the existing studies. We also quantitatively assess the reconstruction difficulty of character and shape objects with the benchmark of the minimum number of speckle images (MNSI) required to achieve a high-quality reconstruction, which can help to comprehend the media's transfer properties.


Asunto(s)
Algoritmos , Diagnóstico por Imagen
17.
J Hazard Mater ; 445: 130512, 2023 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-36463743

RESUMEN

Graphdiyne (GDY) is a novel two-dimensional (2D) carbon allotrope that has attracted much attention in materials, physics, chemistry, and microelectronics for its excellent properties. Much effort has been devoted to exploring the biomedical applications of GDY in 2D carbon nanomaterials, especially for smart drugs and gene delivery. However, few studies have focused on the biocompatibility and potential environmental hazards of GDY and its derivatives. In this study, graphdiyne oxide (GDYO) and graphene oxide (GO) were obtained using different oxidation methods. Their cytotoxicity and hemolysis in vitro and biocompatibility in subcutaneous and peritoneal locations in vivo were compared. GDYO had very low biotoxicity in vitro and was moderately biocompatible in the muscle and abdominal cavity in vivo. Highly oxidized products and graphdiyne quantum dots (GDQDs) were observed in peritoneal cells. GDYO had better biocompatibility and its sheet size was easily diminished through oxidative degradation. Therefore, GDYO is a good candidate for use in 2D carbon nanomaterials in biomedicine.


Asunto(s)
Óxidos , Puntos Cuánticos , Óxidos/toxicidad , Óxidos/química , Puntos Cuánticos/toxicidad , Carbono/química , Oxidación-Reducción
18.
Research (Wash D C) ; 2022: 9825237, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36474603

RESUMEN

The development of small-diameter vascular grafts that can meet the long-term patency required for implementation in clinical practice presents a key challenge to the research field. Although techniques such as the braiding of scaffolds can offer a tunable platform for fabricating vascular grafts, the effects of braided silk fiber skeletons on the porosity, remodeling, and patency in vivo have not been thoroughly investigated. Here, we used finite element analysis of simulated deformation and compliance to design vascular grafts comprised of braided silk fiber skeletons with three different degrees of porosity. Following the synthesis of low-, medium-, and high-porosity silk fiber skeletons, we coated them with hemocompatible sulfated silk fibroin sponges and then evaluated the mechanical and biological functions of the resultant silk tubes with different porosities. Our data showed that high-porosity grafts exhibited higher elastic moduli and compliance but lower suture retention strength, which contrasted with low-porosity grafts. Medium-porosity grafts offered a favorable balance of mechanical properties. Short-term in vivo implantation in rats indicated that porosity served as an effective means to regulate blood leakage, cell infiltration, and neointima formation. High-porosity grafts were susceptible to blood leakage, while low-porosity grafts hindered graft cellularization and tended to induce intimal hyperplasia. Medium-porosity grafts closely mimicked the biomechanical behaviors of native blood vessels and facilitated vascular smooth muscle layer regeneration and polarization of infiltrated macrophages to the M2 phenotype. Due to their superior performance and lack of occlusion, the medium-porosity vascular grafts were evaluated in long-term (24-months) in vivo implantation. The medium-porosity grafts regenerated the vascular smooth muscle cell layers and collagen extracellular matrix, which were circumferentially aligned and resembled the native artery. Furthermore, the formed neoarteries pulsed synchronously with the adjacent native artery and demonstrated contractile function. Overall, our study underscores the importance of braided silk fiber skeleton porosity on long-term vascular graft performance and will help to guide the design of next-generation vascular grafts.

19.
Stem Cell Res Ther ; 13(1): 435, 2022 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-36056394

RESUMEN

BACKGROUND: Skin ageing caused by long-term ultraviolet (UV) irradiation is a complex biological process that involves multiple signalling pathways. Stem cell-conditioned media is believed to have anti-ageing effects on the skin. The purpose of this study was to explore the biological effects of UVB irradiation and anti-photoaging effects of human umbilical cord mesenchymal stem cell-conditioned medium (hUC-MSC-CM) on HaCaT cells using multi-omics analysis with a novel cellular photoaging model. METHODS: A cellular model of photoaging was constructed by irradiating serum-starved HaCaT cells with 20 mJ/cm2 UVB. Transcriptomics and proteomics analyses were used to explore the biological effects of UVB irradiation on photoaged HaCaT cells. Changes in cell proliferation, apoptosis, and migration, the cell cycle, and expression of senescence genes and proteins were measured to assess the protective effects of hUC-MSC-CM in the cellular photoaging model. RESULTS: The results of the multi-omics analysis revealed that UVB irradiation affected various biological functions of cells, including cell proliferation and the cell cycle, and induced a senescence-associated secretory phenotype. hUC-MSC-CM treatment reduced cell apoptosis, inhibited G1 phase arrest in the cell cycle, reduced the production of reactive oxygen species, and promoted cell motility. The qRT-PCR results indicated that MYC, IL-8, FGF-1, and EREG were key genes involved in the anti-photoaging effects of hUC-MSC-CM. The western blotting results demonstrated that C-FOS, C-JUN, TGFß, p53, FGF-1, and cyclin A2 were key proteins involved in the anti-photoaging effects of hUC-MSC-CM. CONCLUSION: Serum-starved HaCaT cells irradiated with 20 mJ/cm2 UVB were used to generate an innovative cellular photoaging model, and hUC-MSC-CM demonstrates potential as an anti-photoaging treatment for skin.


Asunto(s)
Células Madre Mesenquimatosas , Envejecimiento de la Piel , Medios de Cultivo Condicionados/metabolismo , Medios de Cultivo Condicionados/farmacología , Factor 1 de Crecimiento de Fibroblastos/metabolismo , Humanos , Células Madre Mesenquimatosas/metabolismo , Cordón Umbilical
20.
JCI Insight ; 7(12)2022 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-35579950

RESUMEN

Cyclophosphamide (CPA) and doxorubicin (DOX) are key components of chemotherapy for triple-negative breast cancer (TNBC), although suboptimal outcomes are commonly associated with drug resistance and/or intolerable side effects. Through an approach combining high-throughput screening and chemical modification, we developed CN06 as a dual activator of the constitutive androstane receptor (CAR) and nuclear factor erythroid 2-related factor 2 (Nrf2). CN06 enhances CAR-induced bioactivation of CPA (a prodrug) by provoking hepatic expression of CYP2B6, while repressing DOX-induced cytotoxicity in cardiomyocytes in vitro via stimulating Nrf2-antioxidant signaling. Utilizing a multicellular coculture model incorporating human primary hepatocytes, TNBC cells, and cardiomyocytes, we show that CN06 increased CPA/DOX-mediated TNBC cell death via CAR-dependent CYP2B6 induction and subsequent conversion of CPA to its active metabolite 4-hydroxy-CPA, while protecting against DOX-induced cardiotoxicity by selectively activating Nrf2-antioxidant signaling in cardiomyocytes but not in TNBC cells. Furthermore, CN06 preserves the viability and function of human iPSC-derived cardiomyocytes by modulating antioxidant defenses, decreasing apoptosis, and enhancing the kinetics of contraction and relaxation. Collectively, our findings identify CAR and Nrf2 as potentially novel combined therapeutic targets whereby CN06 holds the potential to improve the efficacy/toxicity ratio of CPA/DOX-containing chemotherapy.


Asunto(s)
Cardiotoxicidad , Neoplasias de la Mama Triple Negativas , Antioxidantes/farmacología , Cardiotoxicidad/prevención & control , Receptor de Androstano Constitutivo , Ciclofosfamida , Citocromo P-450 CYP2B6 , Doxorrubicina/farmacología , Humanos , Factor 2 Relacionado con NF-E2/metabolismo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico
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