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1.
Hepatology ; 79(3): 589-605, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37695548

RESUMO

BACKGROUND AND AIMS: Immune cells play a crucial role in liver aging. However, the impact of dynamic changes in the local immune microenvironment on age-related liver injury remains poorly understood. We aimed to characterize intrahepatic immune cells at different ages to investigate key mechanisms associated with liver aging. APPROACH AND RESULTS: We carried out single-cell RNA sequencing on mouse liver tissues at 4 different ages, namely, the newborn, suckling, young, and aged stages. The transcriptomic landscape, cellular classification, and intercellular communication were analyzed. We confirmed the findings by multiplex immunofluorescence staining, flow cytometry, in vitro functional experiments, and chimeric animal models. Nine subsets of 89,542 immune cells with unique properties were identified, of which Cxcl2+ macrophages within the monocyte/macrophage subset were preferentially enriched in the aged liver. Cxcl2+ macrophages presented a senescence-associated secretory phenotype and recruited neutrophils to the aged liver through the CXCL2-CXCR2 axis. Through the secretion of IL-1ß and TNF-α, Cxcl2+ macrophages stimulated neutrophil extracellular traps formation. Targeting the CXCL2-CXCR2 axis limited the neutrophils migration toward the liver and attenuated age-related liver injury. Moreover, the relationship between Cxcl2+ macrophages and neutrophils in age-related liver injury was further validated by human liver transplantation samples. CONCLUSIONS: This in-depth study illustrates that the mechanism of Cxcl2+ macrophage-driven neutrophil activation involves the CXCL2-CXCR2 axis and provides a potential therapeutic strategy for age-related liver injury.


Assuntos
Fígado , Neutrófilos , Camundongos , Animais , Recém-Nascido , Humanos , Idoso , Quimiocina CXCL2 , Macrófagos , Envelhecimento
2.
Opt Express ; 30(6): 9222-9232, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35299356

RESUMO

The application of digital holography in several fields is limited since speckle destroys the original information of the reconstructed image. This paper proposes a neighborhood filter based on multiple sub-reconstructed images according to the random distribution of speckle noise. In this method, the denoised value is equal to the weighted sum of neighboring pixel values, and the weight is calculated by the degree of correlation between different positions of multiple sub-holograms. The experimental results show that the method can greatly reduce the speckle noise, and its noise reduction performance is superior to traditional digital image processing algorithms.

3.
Opt Lett ; 47(2): 397-400, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35030615

RESUMO

This Letter presents a non-local means filter based on the Pearson correlation coefficient and Butterworth high-pass filter. In the method, the new gray value of the denoising pixel is equal to the weighted sum of the surrounding pixel values. We use the Pearson correlation coefficient between the pixels to calculate the weight of the surrounding pixels to the denoising pixel, then use Butterworth high-pass filter to optimize. Experimental results show that the method effectively reduces the speckle noise of digital holography and the image details are also very rich. At the same time, its performance is still better when compared with methods such as BM3D.

4.
Appl Opt ; 61(25): 7474-7481, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36256052

RESUMO

In the field of digital holography, the speckle caused by coherent light greatly disturbs the quality of the reconstruction. This paper presents an innovative method to efficiently reduce speckle noise with a nonlocal means filter based on cosine similarity that determines the weight of each traversal pixel to the target pixel by comparing the similarity between the target pixel neighborhood and the traversal pixel neighborhood. Experimental results with qualitative and quantitative analysis indicate that the proposed method significantly improves noise reduction performance while preserving the details of the original image. Compared with other general image-processing methods, this well-directed method is more in line with the characteristics of holographic speckle noise and has obvious advantages in various metrics.

5.
Appl Opt ; 61(4): 1035-1040, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35201076

RESUMO

In digital holography, the phase is most important, and the quality of the reconstructed phase determines the final reconstructed image effect. However, noise is inevitably introduced in the process of recording the hologram. For regions without object light, the phase has a random distribution, which affects the final phase quality. This kind of noise is called abnormal phase fluctuations in this paper. The correlation between amplitude and phase in digital holography is used to judge whether there is useful phase information. Through structural similarity and the light-dark relationship, a credible probability mask is introduced to extract the phase that needs to be preserved. The simulation and experimental results show that abnormal phase fluctuations are successfully removed, and the useful phase information is retained.

6.
Int J Mol Sci ; 23(23)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36499226

RESUMO

Currently, the production of furan aldehydes from raw biomass suffers from low furfural yield and high energy consumption. In this study, a recyclable and practical method was explored for the preparation of furfural from corn stover by the one-pot reaction by acidic lithium bromide solution (ALBS) without pretreatment and enzymolysis. In the ALBS reaction, the furan aldehydes were generated by the degradation of lignocellulose; however, the products were unstable and were further dehydrated to form humins. So, dehydration reaction was inhibited in this study, and the high yield of furan aldehydes was obtained, in which 2.94 g/L of furfural and 2.78 g/L of 5-hydroxymethyl furfural (5-HMF) were generated with high solid loading (10 wt%), the presence of commercial catalyst ZSM-5 and co-solvent tetrahydrofuran (THF) at 140 °C for 200 min. Via this method, almost 100% of hemicellulose was transformed to furfural, and 40.71% of cellulose was transformed to 5-HMF, which was based on the theoretical yield of HMF (8.35 g) from glucose (29.30 g) produced from cellulose. After the reaction, the catalyst ZSM-5 was the main component in the solid residue and kept a suitable performance. THF azeotrope was easily separated from the slurry by evaporation. During the removal of THF, lignin was precipitated from the liquid phase and showed lower molecular weight and abundant active groups, which was a potential feedstock for producing valuable aromatics and polymers. Thus, in a one-pot reaction, the ideal yield of furan aldehydes from raw biomass was obtained on a lab scale, and the catalyst, THF, and LiBr were easily recycled, which provided an option to realize the economical production of sustainable furan aldehydes from raw biomass.


Assuntos
Aldeídos , Zea mays , Furaldeído/química , Ácidos , Celulose
7.
Med Res Rev ; 40(5): 2049-2084, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32525247

RESUMO

The continuous emergency of drug-resistant cancers and the low specificity of anticancer agents have been the major challenges in the control and treatment of cancer, making an urgent need to develop novel anticancer agents with high efficacy. Chalcones, precursors of flavonoids and isoflavonoids, exhibit structural heterogeneity and can act on various drug targets. Chalcones which demonstrated potential in vitro and in vivo activity against both drug-susceptible and drug-resistant cancers, are useful templates for the development of novel anticancer agents. Hybridization of chalcone moiety with other anticancer pharmacophores could provide the hybrids which have the potential to overcome drug resistance and improve the specificity, so it represents a promising strategy to develop novel anticancer agents. This review emphasizes the development, the mechanisms of action as well as structure-activity relationships of chalcone hybrids with potential therapeutic application for many cancers in recent 10 years.


Assuntos
Antineoplásicos , Chalcona , Chalconas , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Chalcona/farmacologia , Chalcona/uso terapêutico , Chalconas/farmacologia , Chalconas/uso terapêutico , Humanos , Estrutura Molecular , Neoplasias/tratamento farmacológico , Relação Estrutura-Atividade
8.
Stem Cells ; 36(4): 589-601, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29314417

RESUMO

Neural stem/progenitor cells (NSPCs) transplantation provides an alternative approach for various central nervous system (CNS) diseases treatment, while the difficulties in NSPC acquisition and expansion limit their further application. Unveiling the mechanism of NSPC stemness regulation may contribute to its further application. Nestin, generally recognized as a marker of NSPCs, plays a crucial role in the CNS development and NSPC stemness maintenance. Here, we report that Nestin loss triggers mitochondrial network remodeling and enhances oxidative phosphorylation (OXPHOS) in NSPCs treated with Nestin RNA interference (RNAi). Mitochondrial morphology is dynamically controlled by the balance between fission and fusion mediators; one of these mediators, the pro-fission factor, dynamin-related protein 1 (Drp1), shows decreased activation in Nestin-knockdown cells. Upstream, Drp1 phosphorylation is under control of the cytosolic cyclin-dependent kinase 5 (Cdk5). Inhibition of Cdk5 using RNAi or a chemical inhibitor (roscovitine) induces mitochondrial elongation and promotes mitochondrial respiration, indicating that Cdk5-dependent Drp1 phosphorylation participates in mitochondrial metabolism and NSPC stemness regulation. Strikingly, Nestin knockdown results in Cdk5 redistribution, with less remaining in the cytosol, leading to mitochondrial remodeling. We identify Nestin1-640 sequesters Cdk5 in the cytosol and phosphorylates Drp1 subsequently. Together, our results show that a Nestin-Cdk5-Drp1 axis negatively regulates mitochondrial OXPHOS, which is indispensable for the maintenance of NSPC stemness. Stem Cells 2018;36:589-601.


Assuntos
Quinase 5 Dependente de Ciclina/metabolismo , Dinaminas/metabolismo , Mitocôndrias/metabolismo , Nestina/metabolismo , Células-Tronco Neurais/metabolismo , Transdução de Sinais/fisiologia , Animais , Camundongos , Células-Tronco Neurais/citologia , Fosforilação Oxidativa
9.
Bioorg Chem ; 91: 103162, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31382058

RESUMO

In this work, a series of novel moxifloxacin-amide-1,2,3-triazole-isatin hybrids 7a-l were designed and synthesized. The in vitro antibacterial activity against a panel of clinically important Gram-positive and Gram-negative bacteria including drug-resistant pathogens was also evaluated. All hybrids showed considerable activity against the tested pathogens with MIC values of ≤0.03 to 128 µg/mL, and some of them such as hybrids 7e, 7g and 7j were comparable to or better than the parent moxifloxacin (MIC: ≤0.03-8 µg/mL). Moreover, hybrids 7e, 7g and 7j also demonstrated low cytotoxicity towards CHO cells. However, the in vivo pharmacokinetic profiles of these three hybrids were generally far inferior to the parent moxifloxacin. The structure-activity relationship and structure-cytotoxicity relationship were also studied and discussed which may help with the identification of new chemical entities as potent antibacterial agents.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Desenho de Fármacos , Isatina/química , Moxifloxacina/química , Triazóis/química , Infecções Bacterianas/patologia , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
10.
Eur Spine J ; 27(10): 2506-2517, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29086028

RESUMO

PURPOSE: Propionibacterium acnes may be considered a new pathogeny for disc degeneration, but its pathological role has remained unclear. This study was designed to determine whether the latent infection of P. acnes was associated with chronic inflammation in degenerated intervertebral discs via quantification of the levels of a series of cytokines and neutrophils. METHODS: Here, 76 degenerated intervertebral discs were harvested from patients with lower back pain and/or sciatica. Discs with and without P. acnes infection were distinguished and identified using anaerobic culture combined with 16S rDNA PCR and histological examination. Then, cytokines of TNF-α, IL-1ß, IL-6, IL-8, MCP-1, MIP-1α, and IP-10, and the numbers of neutrophils were quantified and compared. The severity of disc degeneration and the prevalence of Modic changes were also evaluated between discs with and without P. acnes. RESULTS: After anaerobic culture and PCR examination, 15 intervertebral discs were placed in the P. acnes-positive group. Another 15 discs were selected from the remaining bacteria-free samples and formed a matched P. acnes-negative group. IL-8, MIP-1α, MCP-1, IP-10, TNF-α, and neutrophils were much higher in P. acnes-positive group than that in the matched P. acnes-negative group. However, only IL-8, MIP-1α, and neutrophils were statistically significant. Furthermore, 7 of 15 P. acnes-positive samples were histologically positive and a subgroup analysis suggested that both histological and PCR-positive samples had the highest concentrations of cytokines of IL-8, MIP-1α, TNF-α, and MCP-1 and the greatest numbers of neutrophils. PCR-positive but histologically negative samples showed the second-greatest, and matched P. acnes-negative samples showed the fewest. However, the difference was only statistically significant between samples found positive under both histology and PCR and samples found negative for P. acnes. Finally, P. acnes-positive group had significantly lower height of intervertebral discs and there was a trend with higher proportion of Modic changes in P. acnes-positive group, but without statistical results. CONCLUSIONS: Latent P. acnes infection was associated with chronic inflammation in degenerated intervertebral discs, especially in the samples with visible bacteria in histology, which manifested as increased numbers of cytokines and neutrophils. Discs with P. acnes infection had much severer disc degeneration and P. acnes-associated chronic inflammation may be the reason.


Assuntos
Infecções por Bactérias Gram-Positivas , Inflamação , Degeneração do Disco Intervertebral , Propionibacterium acnes , Doença Crônica , Infecções por Bactérias Gram-Positivas/complicações , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Inflamação/complicações , Inflamação/epidemiologia , Inflamação/microbiologia , Disco Intervertebral/microbiologia , Degeneração do Disco Intervertebral/complicações , Degeneração do Disco Intervertebral/epidemiologia , Degeneração do Disco Intervertebral/microbiologia , Projetos Piloto
11.
Eur Spine J ; 24(11): 2496-502, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26287263

RESUMO

PURPOSE: Propionibacterium acnes (P. acnes) in the intervertebral disc may result in low back pain. The purpose of this study was to determine how P. acnes accesses the disc. METHODS: Patients with low back pain and/or sciatica were examined using X-ray and MRI before surgery. The intervertebral disc space height was measured on X-ray image. Disc and muscle samples were obtained from 46 patients undergoing discectomy at the lumbar spine. The tear of annulus was inspected before discectomy. In the disc and muscle tissue cultures, 16S rDNA gene specific for P. acnes was examined using PCR. RESULTS: The discs from 11 (23.9 %) patients were identified as 16S rDNA positive, in which two patients also had 16S rDNA in their muscles. 16S rDNA gene was significantly more likely to appear in the discs with annular tear than those without tear (P < 0.05). The disc space height was significantly decreased when the disc contained P. acnes. CONCLUSION: P. acnes is significantly more likely to be present in herniated discs with an annular tear than in herniated discs without such a tear. Since in the vast majority of these cases, no P. acnes was found in control muscle samples, a true infection with P. acnes is far more likely than a contamination.


Assuntos
Disco Intervertebral/microbiologia , Dor Lombar/microbiologia , Vértebras Lombares/microbiologia , Propionibacterium acnes/isolamento & purificação , Adulto , Idoso , DNA Bacteriano/análise , Discotomia , Feminino , Infecções por Bactérias Gram-Positivas , Humanos , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/lesões , Disco Intervertebral/cirurgia , Deslocamento do Disco Intervertebral/microbiologia , Deslocamento do Disco Intervertebral/cirurgia , Dor Lombar/diagnóstico por imagem , Vértebras Lombares/cirurgia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , RNA Ribossômico 16S/análise , Radiografia , Ciática/microbiologia , Adulto Jovem
12.
Proc Natl Acad Sci U S A ; 109(24): 9281-6, 2012 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-22623525

RESUMO

Surface enhanced Raman spectroscopy (SERS) is an attractive analytical technique, which enables single-molecule sensitive detection and provides its special chemical fingerprints. During the past decades, researchers have made great efforts towards an ideal SERS substrate, mainly including pioneering works on the preparation of uniform metal nanostructure arrays by various nanoassembly and nanotailoring methods, which give better uniformity and reproducibility. Recently, nanoparticles coated with an inert shell were used to make the enhanced Raman signals cleaner. By depositing SERS-active metal nanoislands on an atomically flat graphene layer, here we designed a new kind of SERS substrate referred to as a graphene-mediated SERS (G-SERS) substrate. In the graphene/metal combined structure, the electromagnetic "hot" spots (which is the origin of a huge SERS enhancement) created by the gapped metal nanoislands through the localized surface plasmon resonance effect are supposed to pass through the monolayer graphene, resulting in an atomically flat hot surface for Raman enhancement. Signals from a G-SERS substrate were also demonstrated to have interesting advantages over normal SERS, in terms of cleaner vibrational information free from various metal-molecule interactions and being more stable against photo-induced damage, but with a comparable enhancement factor. Furthermore, we demonstrate the use of a freestanding, transparent and flexible "G-SERS tape" (consisting of a polymer-layer-supported monolayer graphene with sandwiched metal nanoislands) to enable direct, real time and reliable detection of trace amounts of analytes in various systems, which imparts high efficiency and universality of analyses with G-SERS substrates.

13.
Front Endocrinol (Lausanne) ; 15: 1358278, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948522

RESUMO

Objective: This study aims to determine whether the live birth rates were similar between GnRH antagonist original reference product Cetrotide® and generic Ferpront®, in gonadotropin-releasing hormone (GnRH) antagonist protocol for controlled ovarian stimulation (COS). Methods: This retrospective cohort study investigates COS cycles utilizing GnRH antagonist protocols. The research was conducted at a specialized reproductive medicine center within a tertiary care hospital, spanning the period from October 2019 to October 2021. Within this timeframe, a total of 924 cycles were administered utilizing the GnRH antagonist originator, Cetrotide® (Group A), whereas 1984 cycles were undertaken using the generic, Ferpront® (Group B). Results: Ovarian reserve markers, including anti-Mullerian hormone, antral follicle number, and basal follicular stimulating hormone, were lower in Group A compared to Group B. Propensity score matching (PSM) was performed to balance these markers between the groups. After PSM, baseline clinical features were similar, except for a slightly longer infertile duration in Group A versus Group B (4.43 ± 2.92 years vs. 4.14 ± 2.84 years, P = 0.029). The duration of GnRH antagonist usage was slightly longer in Group B than in Group A (6.02 ± 1.41 vs. 5.71 ± 1.48 days, P < 0.001). Group B had a slightly lower number of retrieved oocytes compared to Group A (14.17 ± 7.30 vs. 14.96 ± 7.75, P = 0.024). However, comparable numbers of usable embryos on day 3 and good-quality embryos were found between the groups. Reproductive outcomes, including biochemical pregnancy loss, clinical pregnancy, miscarriage, and live birth rate, did not differ significantly between the groups. Multivariate logistic regression analyses suggested that the type of GnRH antagonist did not independently impact the number of oocytes retrieved, usable embryos, good-quality embryos, moderate to severe OHSS rate, clinical pregnancy, miscarriage, or live birth rate. Conclusion: The retrospective analysis revealed no clinically significant differences in reproductive outcomes between Cetrotide® and Ferpront® when used in women undergoing their first and second COS cycles utilizing the GnRH antagonist protocol.


Assuntos
Hormônio Liberador de Gonadotropina , Antagonistas de Hormônios , Indução da Ovulação , Humanos , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hormônio Liberador de Gonadotropina/análogos & derivados , Feminino , Estudos Retrospectivos , Indução da Ovulação/métodos , Gravidez , Adulto , Antagonistas de Hormônios/uso terapêutico , Antagonistas de Hormônios/administração & dosagem , Antagonistas de Hormônios/efeitos adversos , Taxa de Gravidez , Coeficiente de Natalidade , Medicamentos Genéricos/uso terapêutico , Reserva Ovariana/efeitos dos fármacos
14.
Plant Commun ; 5(4): 100834, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38327057

RESUMO

ATP is the primary form of energy for plants, and a shortage of cellular ATP is generally acknowledged to pose a threat to plant growth and development, stress resistance, and crop quality. The overall metabolic processes that contribute to the ATP pool, from production, dissipation, and transport to elimination, have been studied extensively. Considerable evidence has revealed that in addition to its role in energy supply, ATP also acts as a regulatory signaling molecule to activate global metabolic responses. Identification of the eATP receptor DORN1 contributed to a better understanding of how plants cope with disruption of ATP homeostasis and of the key points at which ATP signaling pathways intersect in cells or whole organisms. The functions of SnRK1α, the master regulator of the energy management network, in restoring the equilibrium of the ATP pool have been demonstrated, and the vast and complex metabolic network mediated by SnRK1α to adapt to fluctuating environments has been characterized. This paper reviews recent advances in understanding the regulatory control of the cellular ATP pool and discusses possible interactions among key regulators of ATP-pool homeostasis and crosstalk between iATP/eATP signaling pathways. Perception of ATP deficit and modulation of cellular ATP homeostasis mediated by SnRK1α in plants are discussed at the physiological and molecular levels. Finally, we suggest future research directions for modulation of plant cellular ATP homeostasis.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Trifosfato de Adenosina/metabolismo , Transdução de Sinais , Homeostase
15.
Med Oncol ; 41(3): 75, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38381181

RESUMO

Lenvatinib is a multitargeted tyrosine kinase inhibitor capable of promoting apoptosis, suppressing angiogenesis, inhibiting tumor cell proliferation, and modulating the immune response. In multiple cancer types, lenvatinib has presented manageable safety and is currently approved as an effective first-line therapy. However, with the gradual increase in lenvatinib application, the inevitable progression of resistance to lenvatinib is becoming more prevalent. A series of recent researches have reported the mechanisms underlying the development of lenvatinib resistance in tumor therapy, which are related to the regulation of cell death or proliferation, histological transformation, metabolism, transport processes, and epigenetics. In this review, we aim to outline recent discoveries achieved in terms of the mechanisms and potential predictive biomarkers of lenvatinib resistance as well as to summarize untapped approaches available for improving the therapeutic efficacy of lenvatinib in patients with various types of cancers.


Assuntos
Apoptose , Epigênese Genética , Compostos de Fenilureia , Quinolinas , Humanos , Biomarcadores , Proliferação de Células
16.
Heart Lung ; 67: 53-61, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38701700

RESUMO

BACKGROUND: The association between coffee and caffeine intake and the risk of COPD and lung function has not been thoroughly discussed in Americans, with subgroup and threshold effects remaining unclear. OBJECTIVES: This study investigated the association between coffee and caffeine consumption and the risk of chronic obstructive pulmonary disease (COPD) as well as lung function utilizing data from the NHANES 2007-2012. METHODS: We assessed the associations of coffee and caffeine consumption with the risk of COPD and lung function parameters, including FEV1 and FVC, adjusting for common demographic and disease characteristics in a cross-sectional analysis of NHANES data. RESULTS: A total of 9763 participants were included in the study, and 592 were diagnosed with COPD. Multivariate regression models revealed positive associations between coffee and caffeine consumption and the risk of COPD and lung function. Subgroup analyses stratified by sex, DM, hypertension status, and smoking habits identified potential effect modifiers as well as inflection points from threshold effect examinations. CONCLUSIONS: The results of this cross-sectional study indicated significant positive correlations between coffee and caffeine consumption and the risk of COPD. Additionally, positive correlations between exposure variables and FEV1 and FVC were detected. Among the stratification factors, smoking status exhibited the most potential for modifying effects. Future practices and research are needed to validate the results and explore the underlying mechanisms.


Assuntos
Cafeína , Café , Inquéritos Nutricionais , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Café/efeitos adversos , Masculino , Feminino , Cafeína/efeitos adversos , Cafeína/administração & dosagem , Estudos Transversais , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Fatores de Risco , Idoso , Adulto , Volume Expiratório Forçado
17.
Adv Sci (Weinh) ; 11(32): e2404171, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39031840

RESUMO

Hepatic ischemia-reperfusion injury (HIRI) is a prevalent issue during liver resection and transplantation, with currently no cure or FDA-approved therapy. A promising drug, Cyclosporin A (CsA), ameliorates HIRI by maintaining mitochondrial homeostasis but has systemic side effects due to its low bioavailability and high dosage requirements. This study introduces a biomimetic CsA delivery system that directly targets hepatic lesions using mesenchymal stem cell (MSC) membrane-camouflaged liposomes. These hybrid nanovesicles (NVs), leveraging MSC-derived proteins, demonstrate efficient inflammatory chemotaxis, transendothelial migration, and drug-loading capacity. In a HIRI mouse model, the biomimetic NVs accumulated at liver injury sites entered hepatocytes, and significantly reduced liver damage and restore function using only one-tenth of the CsA dose typically required. Proteomic analysis verifies the protection mechanism, which includes reactive oxygen species inhibition, preservation of mitochondrial integrity, and reduced cellular apoptosis, suggesting potential for this biomimetic strategy in HIRI intervention.


Assuntos
Ciclosporina , Modelos Animais de Doenças , Lipossomos , Células-Tronco Mesenquimais , Traumatismo por Reperfusão , Animais , Ciclosporina/farmacologia , Ciclosporina/administração & dosagem , Traumatismo por Reperfusão/prevenção & controle , Camundongos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Biomimética/métodos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Masculino , Camundongos Endogâmicos C57BL
18.
Nat Commun ; 15(1): 4760, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834654

RESUMO

Older livers are more prone to hepatic ischaemia/reperfusion injury (HIRI), which severely limits their utilization in liver transplantation. The potential mechanism remains unclear. Here, we demonstrate older livers exhibit increased ferroptosis during HIRI. Inhibiting ferroptosis significantly attenuates older HIRI phenotypes. Mass spectrometry reveals that fat mass and obesity-associated gene (FTO) expression is downregulated in older livers, especially during HIRI. Overexpressing FTO improves older HIRI phenotypes by inhibiting ferroptosis. Mechanistically, acyl-CoA synthetase long chain family 4 (ACSL4) and transferrin receptor protein 1 (TFRC), two key positive contributors to ferroptosis, are FTO targets. For ameliorative effect, FTO requires the inhibition of Acsl4 and Tfrc mRNA stability in a m6A-dependent manner. Furthermore, we demonstrate nicotinamide mononucleotide can upregulate FTO demethylase activity, suppressing ferroptosis and decreasing older HIRI. Collectively, these findings reveal an FTO-ACSL4/TFRC regulatory pathway that contributes to the pathogenesis of older HIRI, providing insight into the clinical translation of strategies related to the demethylase activity of FTO to improve graft function after older donor liver transplantation.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato , Coenzima A Ligases , Ferroptose , Fígado , Receptores da Transferrina , Traumatismo por Reperfusão , Regulação para Cima , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia , Animais , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Ferroptose/genética , Fígado/metabolismo , Fígado/patologia , Camundongos , Receptores da Transferrina/metabolismo , Receptores da Transferrina/genética , Masculino , Coenzima A Ligases/metabolismo , Coenzima A Ligases/genética , Camundongos Endogâmicos C57BL , Humanos , Transplante de Fígado , Estabilidade de RNA/genética , Antígenos CD
19.
Artigo em Inglês | MEDLINE | ID: mdl-37624506

RESUMO

Deoxynivalenol (DON) is a mycotoxin that significantly threatens the food and feed industry. Corn steep liquor (CSL) is an acidic byproduct of the corn starch industry, and DON is concentrated in CSL once the material is contaminated. In this work, a Pichia kudriavzevii strain that could remove DON from CSL was isolated and characterized. The strain P. kudriavzevii E4-205 showed detoxifying activity in a pH range of 4.0~7.0 and temperature of 25~42 °C, and 39.4% DON was reduced by incubating this strain in CSL supernatant diluted by 2-fold (5 µg/mL DON) for 48 h at pH 5.0 and 30 °C. Further mechanism studies showed that P. kudriavzevii E4-205 could adsorb DON by the cell wall and degrade DON by intracellular enzymes with NADH as a cofactor. The degradation product was identified as 3,7,8,15-tetrahydroxyscirpene by liquid chromatography-tandem mass spectrometry. DON adsorption by inactivated cells was characterized, and the adsorption followed pseudo first-order kinetics. This study revealed a novel mechanism by which microbes degrade DON and might serve as a guide for the development of DON biological detoxification methods.

20.
Cell Death Discov ; 9(1): 273, 2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37507381

RESUMO

The therapeutic potential of umbilical cord-mesenchymal stem cell (UC-MSC) transplantation in liver fibrosis has been highlighted. However, the fate of transplanted MSCs in the fibrotic microenvironment remains unclear. In this study, we aim to uncover the fate of transplanted MSCs and develop targeting strategies that could enhance the therapeutic efficacy of MSC therapy in liver fibrosis. We used human UC-MSCs as the study object. For in vitro experiments, we stimulated UC-MSCs with several fibrotic-related factors (Liver fibrotic Factors, LF), including TGFß, TNFα and IFNγ for downstream investigations. We co-cultured LF-treated UC-MSCs with hepatic stellate cell line LX-2 to assess the anti-fibrotic effect. We showed that upon LF stimulation, UC-MSCs exhibited reduced anti-fibrotic activity and underwent rapid senescence. Pathway analysis showed that JAK/STAT3 signaling was highly activated upon LF stimulation, which significantly elevated senescence-associated secretory phenotype (SASP) and senescence in UC-MSCs and could be reversed by a specific JAK inhibitor AG490. Moreover, using both carbon tetrachloride (CCl4) and 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induce fibrosis models, we demonstrated that AG490 pretreatment promoted UC-MSCs survival within the fibrotic liver microenvironment and exhibited enhance therapeutic efficacy. Overall, we showed that targeting MSC senescence in vivo through AG490 pretreatment could enhance the anti-fibrotic activities of UC-MSCs.

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