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1.
Materials (Basel) ; 17(15)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39124442

RESUMEN

Engineered geopolymer composites (EGCs) exhibit excellent tensile ductility and crack control ability, making them promising for concrete structure repair. However, their widespread use is limited by high costs of reinforcement fiber and a lack of an EGC-concrete interface bonding mechanism. This study investigated a hybrid PE/PVA fiber-reinforced EGC using domestically produced unoiled PVA fibers to replace commonly used PE fibers. The bond performance of the EGC-concrete interface was evaluated through direct tensile and slant shear tests, focusing on the effects of PE fiber content (1%, 2%, and 3%), fiber hybrid ratios (2.0:0.0, 1.5:0.5, 1.0:1.0, 0.5:1.5, and 0.0:2.0), concrete substrate strength (C30, C50, and C70), and the ratio of fly ash (FA) to ground granulated blast furnace slag (GGBS) (6:4, 7:3, and 8:2) on interface bond strength. Results showed that the EGCs' compressive strength ranged from 77.1 to 108.9 MPa, with increased GGBS content significantly enhancing the compressive strength and elastic modulus. Most of the specimens exhibited strain-hardening behavior after initial cracking. Interface bonding tests revealed that a PE/PVA ratio of 1.0 increased tensile bond strength by 8.5% compared with using 2.0% PE fiber alone. Increasing the PE fiber content, PVA/PE ratio, GGBS content, and concrete substrate strength all improved the shear bond strength. This improvement was attributed to the flexible fibers' ability to restrict thermo-hydro damage and deflect and blunt microcracks, enhancing the interface's failure resistance. Cost analysis showed that replacing 50% of the PE fiber in EGC with unoiled PVA fiber reduced costs by 44.2% compared with PE fiber alone, offering the best cost-performance ratio. In summary, hybrid PE/PVA fiber EGC has promising prospects for improving economic efficiency while maintaining tensile ductility and crack-control ability. Future optimization of fiber ratios and interface design could further enhance its potential for concrete repair applications.

2.
Small ; : e2401194, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38984765

RESUMEN

High-sensitive uncooled mid-wave infrared (MWIR) photodetection with fast speed is highly desired for biomedical imaging, optical communication, and night vision technology. Low-dimensional materials with low dark current and broadband photoresponse hold great promise for use in MWIR detection. Here, this study reports a high-performance MWIR photodetector based on a titanium trisulfide (TiS3) nanoribbon. This device demonstrates an ultra-broadband photoresponse ranging from the visible spectrum to the MWIR spectrum (405-4275 nm). In the MWIR spectral range, the photodetector achieves competitive high photoresponsivity (R) of 21.1 A W-1, and an impressive specific detectivity (D*) of 5.9 × 1010 cmHz1/2 W-1 in ambient air. Remarkably, the photoresponse speed in the MWIR with τr = 1.3 ms and τd = 1.5 ms is realized which is much faster than the thermal time constant of 15 ms. These findings pave the way for highly sensitive, room-temperature MWIR photodetectors with exceptionally fast response speed.

3.
JMIR Mhealth Uhealth ; 12: e50783, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38833298

RESUMEN

BACKGROUND: Young women often face substantial psychological challenges in the initial years following cancer diagnosis, leading to a comparatively lower quality of life than older survivors. While mobile apps have emerged as potential interventions, their effectiveness remains inconclusive due to the diversity in intervention types and variation in follow-up periods. Furthermore, there is a particular dearth of evidence regarding the efficacy of these apps' intelligent features in addressing psychological distress with these apps. OBJECTIVE: This study aims to evaluate the effectiveness of a mobile app with intelligent design called "AI-TA" on cancer-related psychological health and ongoing symptoms with a randomized controlled design. METHODS: Women aged 18 to 45 years diagnosed with breast cancer were randomly assigned to the intervention or control group. The intervention was AI-TA, which included 2-way web-based follow-up every 2 weeks. Both intention-to-treat (ITT) and per-protocol (PP) analyses employed repeated measurement analysis of variance. The participants' background features, primary outcomes (psychological distress and frequency, self-efficacy, and social support), and secondary outcomes (quality of life) were measured using multiple instruments at 3 time points (baseline, 1-month intervention, and 3-month intervention). RESULTS: A total of 124 participants were randomly allocated to the control group (n=62, 50%) or intervention group (n=62, 50%). In total, 92.7% (115/124) of the participants completed the intervention. Significant improvements in psychological symptoms (Memorial Symptom Assessment Scale-Short Form) were observed in the ITT group from baseline to 1-month intervention relative to the control group (ITT vs control: 1.17 vs 1.23; P<.001), which persisted at 3-month follow-up (ITT vs control: 0.68 vs 0.91; P<.001). Both the ITT and PP groups exhibited greater improvements in self-efficacy (Cancer Behavior Inventory-Brief Version) than the control group at 1-month (ITT vs PP vs control: 82.83 vs 77.12 vs 65.35; P<.001) and 3-month intervention (ITT vs PP vs control: 92.83 vs 89.30 vs 85.65; P<.001). However, the change in social support (Social Support Rating Scale) did not increase significantly until 3-month intervention (ITT vs control: 50.09 vs 45.10; P=.002) (PP vs control: 49.78 vs 45.10; P<.001). All groups also experienced beneficial effects on quality of life (Functional Assessment of Cancer Therapy-Breast), which persisted at 3-month follow-up (P<.001). CONCLUSIONS: The intelligent mobile app AI-TA incorporating intelligent design shows promise for reducing psychological and cancer-related symptoms among young survivors of breast cancer. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2200058823; https://www.chictr.org.cn/showproj.html?proj=151195.


Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Aplicaciones Móviles , Calidad de Vida , Humanos , Femenino , Aplicaciones Móviles/normas , Aplicaciones Móviles/estadística & datos numéricos , Neoplasias de la Mama/psicología , Neoplasias de la Mama/terapia , Adulto , Persona de Mediana Edad , Adolescente , Supervivientes de Cáncer/psicología , Supervivientes de Cáncer/estadística & datos numéricos , Calidad de Vida/psicología , Encuestas y Cuestionarios , Autoeficacia
6.
Nature ; 628(8008): 630-638, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38538795

RESUMEN

Lysosomes are degradation and signalling centres crucial for homeostasis, development and ageing1. To meet diverse cellular demands, lysosomes remodel their morphology and function through constant fusion and fission2,3. Little is known about the molecular basis of fission. Here we identify HPO-27, a conserved HEAT repeat protein, as a lysosome scission factor in Caenorhabditis elegans. Loss of HPO-27 impairs lysosome fission and leads to an excessive tubular network that ultimately collapses. HPO-27 and its human homologue MROH1 are recruited to lysosomes by RAB-7 and enriched at scission sites. Super-resolution imaging, negative-staining electron microscopy and in vitro reconstitution assays reveal that HPO-27 and MROH1 self-assemble to mediate the constriction and scission of lysosomal tubules in worms and mammalian cells, respectively, and assemble to sever supported membrane tubes in vitro. Loss of HPO-27 affects lysosomal morphology, integrity and degradation activity, which impairs animal development and longevity. Thus, HPO-27 and MROH1 act as self-assembling scission factors to maintain lysosomal homeostasis and function.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Lisosomas , Animales , Humanos , Caenorhabditis elegans/citología , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/ultraestructura , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/ultraestructura , Homeostasis , Longevidad , Lisosomas/metabolismo , Lisosomas/ultraestructura , Secuencias de Aminoácidos , Microscopía Electrónica
7.
ACS Nano ; 18(12): 8961-8970, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38470346

RESUMEN

Valley excitons dominate the optoelectronic response of transition-metal dichalcogenides and are drastically affected by structural and environmental inhomogeneities localized in these materials. Critical to understanding and controlling these nanoscale excitonic changes is the ability to correlate the imaging of excitonic states with crystalline structures on the atomic scale. Here, we apply scanning tunneling microscope-induced luminescence microscopy to image valley excitons in a semiconducting transition-metal dichalcogenide monolayer decoupled by a 10 nanometer-thick hexagonal-boron-nitride flake incorporated in a lateral homojunction on an Au electrode surface. This design enables the observation of chiral excitonic emission arising from neutral and charged valley excitons of the monolayer semiconductor at ambipolar voltages with a quantum efficiency up to ∼10-5 photon/electron. The measured light helicity demonstrates considerable circular polarization dependent on the sample voltage, reaching as much as 40%. The real-space luminescence imaging maps─at subnanometer resolution─of the valley excitons reveal striking spatial variations associated with localized inhomogeneities, including surface impurities and possibly nanoscale dielectric and/or potential disorders in the monolayer. Our study introduces a promising format for 2D materials to explore and tailor their optoelectronic processes at the atomic scale.

8.
Cell Rep ; 42(8): 112822, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37471224

RESUMEN

C9orf72 repeat expansions are the most common genetic cause of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS). Poly(GR) proteins are toxic to neurons by forming cytoplasmic inclusions that sequester RNA-binding proteins including stress granule (SG) proteins. However, little is known of the factors governing poly(GR) inclusion formation. Here, we show that poly(GR) infiltrates a finely tuned network of protein-RNA interactions underpinning SG formation. It interacts with G3BP1, the key driver of SG assembly and a protein we found is critical for poly(GR) inclusion formation. Moreover, we discovered that N6-methyladenosine (m6A)-modified mRNAs and m6A-binding YTHDF proteins not only co-localize with poly(GR) inclusions in brains of c9FTD/ALS mouse models and patients with c9FTD, they promote poly(GR) inclusion formation via the incorporation of RNA into the inclusions. Our findings thus suggest that interrupting interactions between poly(GR) and G3BP1 or YTHDF1 proteins or decreasing poly(GR) altogether represent promising therapeutic strategies to combat c9FTD/ALS pathogenesis.


Asunto(s)
Esclerosis Amiotrófica Lateral , Demencia Frontotemporal , Animales , Ratones , Humanos , Esclerosis Amiotrófica Lateral/patología , ADN Helicasas/metabolismo , Gránulos de Estrés , Expansión de las Repeticiones de ADN , Proteínas de Unión a Poli-ADP-Ribosa/genética , Proteínas de Unión a Poli-ADP-Ribosa/metabolismo , ARN Helicasas/genética , ARN Helicasas/metabolismo , Proteínas con Motivos de Reconocimiento de ARN/metabolismo , Demencia Frontotemporal/metabolismo , Cuerpos de Inclusión/metabolismo , Proteínas de Choque Térmico/metabolismo , ARN/metabolismo , Proteína C9orf72/genética , Proteína C9orf72/metabolismo
9.
Acta Pharmacol Sin ; 44(8): 1687-1700, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36964308

RESUMEN

Aberrant NLRP3 activation has been implicated in the pathogenesis of numerous inflammation-associated diseases. However, no small molecular inhibitor that directly targets NLRP3 inflammasome has been approved so far. In this study, we show that Atranorin (C19H18O8), the secondary metabolites of lichen family, effectively prevents NLRP3 inflammasome activation in macrophages and dendritic cells. Mechanistically, Atranorin inhibits NLRP3 activation induced cytokine secretion and cell pyroptosis through binding to ASC protein directly and therefore restraining ASC oligomerization. The pharmacological effect of Atranorin is evaluated in NLRP3 inflammasome-driven disease models. Atranorin lowers serum IL-1ß and IL-18 levels in LPS induced mice acute inflammation model. Also, Atranorin protects against MSU crystal induced mice gouty arthritis model and lowers ankle IL-1ß level. Moreover, Atranorin ameliorates intestinal inflammation and epithelial barrier dysfunction in DSS induced mice ulcerative colitis and inhibits NLRP3 inflammasome activation in colon. Altogether, our study identifies Atranorin as a novel NLRP3 inhibitor that targets ASC protein and highlights the potential therapeutic effects of Atranorin in NLRP3 inflammasome-driven diseases including acute inflammation, gouty arthritis and ulcerative colitis.


Asunto(s)
Artritis Gotosa , Colitis Ulcerosa , Ratones , Animales , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Artritis Gotosa/tratamiento farmacológico , Artritis Gotosa/metabolismo , Inflamación/metabolismo , Interleucina-1beta/metabolismo , Ratones Endogámicos C57BL
10.
Emerg Microbes Infect ; 12(1): 2149353, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36395071

RESUMEN

Numerous vaccines have been developed to address the current COVID-19 pandemic, but safety, cross-neutralizing efficacy, and long-term protectivity of currently approved vaccines are still important issues. In this study, we developed a subunit vaccine, ASD254, by using a nanoparticle vaccine platform to encapsulate the SARS-CoV-2 spike receptor-binding domain (RBD) protein. As compared with the aluminum-adjuvant RBD vaccine, ASD254 induced higher titers of RBD-specific antibodies and generated 10- to 30-fold more neutralizing antibodies. Mice vaccinated with ASD254 showed protective immune responses against SARS-CoV-2 challenge, with undetectable infectious viral loads and reduced typical lesions in lung. Besides, neutralizing antibodies in vaccinated mice lasted for at least one year and were effective against various SARS-CoV-2 variants of concern, including B.1.1.7 (Alpha), B.1.351 (Beta), P.1 (Gamma), B.1.617.2 (Delta), and B.1.1.529 (Omicron). Furthermore, particle size, polydispersity index, and zeta-potential of ASD254 remained stable after 8-month storage at 4°C. Thus, ASD254 is a promising nanoparticle vaccine with good immunogenicity and stability to be developed as an effective vaccine option in controlling upcoming waves of COVID-19.


Asunto(s)
Anticuerpos Neutralizantes , Vacunas contra la COVID-19 , COVID-19 , Nanopartículas , Animales , Humanos , Ratones , Anticuerpos Antivirales , COVID-19/prevención & control , Pandemias , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/genética , Vacunas de Subunidad/inmunología , Vacunas contra la COVID-19/inmunología
11.
J Photochem Photobiol B ; 238: 112604, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36525776

RESUMEN

Ultraviolet-B (UVB) exposure on the skin triggers apoptosis, oxidative stress and acute inflammatory responses, which eventually increases the risk of various skin disorders. Hemin, an iron-binding porphyrin, has been clinically used for porphyria treatment. However, whether hemin contributes to the skin protection against UVB injury remains to be elucidated. Here, we found that hemin treatment (10 and 20 mg/kg) by intraperitoneal administration could dramatically relieve UVB irradiation-induced skin damage featured by erythema, edema, epidermal hyperplasia and collagen loss in C57BL/6 J mice. Importantly, hemin treatment attenuated UVB irradiation-triggered cell apoptosis in skin epidermis. Consistently, hemin (10, 20 µM) treatment decreased Caspase-3 activation and protected against UVB-induced apoptosis in HaCaT cells. Besides, hemin treatment reduced the infiltration of neutrophils in skin under UVB irradiation, thus restrained neutrophil extracellular traps (NET) formation and myeloperoxidase (MPO) release. We further revealed that hemin inhibited the expression of inflammation associated cytokines and chemokines in UVB-induced HaCaT cells and blocked the chemotaxis of dHL-60 cells to preconditioned media from HaCaT culture upon UVB irradiation. Furthermore, hemin inhibited the excessive maturation and mobilization of bone marrow neutrophils and rectified the proportion of abnormally elevated neutrophils in the blood under UVB irradiation. In conclusion, our study showed that hemin treatment protects against UVB-induced skin damage through inhibiting keratinocytes apoptosis, and suppressing neutrophils infiltration in the skin via externally restraining the keratinocyte attraction and internally regulating bone marrow neutrophil maturation and mobilization, suggesting that hemin is an effective drug candidate for the therapy of UVB damage.


Asunto(s)
Hemina , Enfermedades de la Piel , Ratones , Animales , Hemina/farmacología , Hemina/metabolismo , Infiltración Neutrófila , Ratones Endogámicos C57BL , Piel/metabolismo , Queratinocitos/metabolismo , Apoptosis , Inflamación/metabolismo , Rayos Ultravioleta
12.
Mater Today Bio ; 17: 100480, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36353390

RESUMEN

Most existing vaccines use activators that polarize the immune response to T-helper (Th) 2 response for antibody production. Our positively charged chitosan (Cs)-based nanocomplex (CNC) drives the Th1 response through unknown mechanisms. As receptors for the positively charged CNC are not determined, the physico-chemical properties are hypothesized to correlate with its immunomodulatory effects. To clarify the effects of surface charge and size on the immune response, smaller CNC and negatively charged CNC encapsulating ovalbumin are tested on dendritic cell (DC) 2.4 â€‹cells. The negatively charged CNC loses activity, but the smaller CNC does not. To further evaluate the material effects, we replace Cs by poly-amino acids. Compared with the negatively charged nanocomplex, the positively charged one preserves its activity. Using immature bone marrow-derived DCs (BMDC) enriched from BALB/c mice as a model to analyze DC differentiation, treatments with positively charged nanocomplexes evidently increase the proportions of Langerin+ dermal DC, CD11blo interstitial DC, and CD8a+ conventional DC. Additionally, vaccination with two doses containing positively charged nanocomplexes are safe and increase ovalbumin-specific IgG and recall T-cell responses in mice. Overall, a positive charge seems to contribute to the immunological effect of nanocomplexes on elevating the Th1 response by modulating DC differentiation.

13.
Nano Lett ; 22(23): 9630-9637, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36383028

RESUMEN

Two-dimensional transition metal dichalcogenides (TMDs) have shown great importance in the development of novel ultrathin optoelectronic devices owing to their exceptional electronic and photonic properties. Effectively tuning their electronic band structures is not only desired in electronics applications but also can facilitate more novel properties. In this work, we demonstrate that large electronic tuning on a WSe2 monolayer can be realized by different facets of a Au-foil substrate, forming in-plane p-n junctions with remarkable built-in electric fields. This facet-dependent tuning effect is directly visualized by using scanning tunneling microscopy and differential conductance (dI/dV) spectroscopy. First-principles calculations reveal that the atomic arrangement of the Au facet effectively changes the interfacial coupling and charge transfer, leading to different magnitudes of charge doping in WSe2. Our study would be beneficial for future customized fabrication of TMD-junction devices via facet-specific construction on the substrate.

14.
Science ; 378(6615): 94-99, 2022 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-36201573

RESUMEN

Frontotemporal dementia and amyotrophic lateral sclerosis (FTD-ALS) are associated with both a repeat expansion in the C9orf72 gene and mutations in the TANK-binding kinase 1 (TBK1) gene. We found that TBK1 is phosphorylated in response to C9orf72 poly(Gly-Ala) [poly(GA)] aggregation and sequestered into inclusions, which leads to a loss of TBK1 activity and contributes to neurodegeneration. When we reduced TBK1 activity using a TBK1-R228H (Arg228→His) mutation in mice, poly(GA)-induced phenotypes were exacerbated. These phenotypes included an increase in TAR DNA binding protein 43 (TDP-43) pathology and the accumulation of defective endosomes in poly(GA)-positive neurons. Inhibiting the endosomal pathway induced TDP-43 aggregation, which highlights the importance of this pathway and TBK1 activity in pathogenesis. This interplay between C9orf72, TBK1, and TDP-43 connects three different facets of FTD-ALS into one coherent pathway.


Asunto(s)
Esclerosis Amiotrófica Lateral , Proteína C9orf72 , Proteínas de Unión al ADN , Demencia Frontotemporal , Proteínas Serina-Treonina Quinasas , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/metabolismo , Animales , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Expansión de las Repeticiones de ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Endosomas/metabolismo , Demencia Frontotemporal/genética , Demencia Frontotemporal/metabolismo , Ratones , Mutación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo
15.
Colloids Surf B Biointerfaces ; 220: 112897, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36215893

RESUMEN

Poor long-term stability and formation of irreversible aggregates when subjected to a freeze-drying process greatly limits the clinical application of gold nanoparticles (GNPs) as a vaccine carrier. In this study, we synthesized a GNP-antigen conjugate with high colloidal stability by using a thiolated polyethylene glycol (PEG) linker to conjugate a model antigen (ovalbumin; OVA) onto the GNP surface (i.e. GNP-OVA) and demonstrated this conjugate had self-adjuvanting properties to augment antigen-specific immune responses. The synthesized GNP had an average hydrodynamic size of 13.8 ± 2.1 nm (n = 3); after conjugation of OVA, the diameter increased to 28.6 ± 7.3 nm (n = 3). The obtained GNP-OVA can maintain a stable dispersion state in aqueous solutions for at least 12 months and withstand stresses during lyophilization without creating irreversible aggregates. Compared with OVA alone or a mixture of PEG-functionalized GNP (GNP-PEG) and OVA (i.e. GNP-PEG/OVA), the chemical conjugation of OVA onto GNP-PEG substantially increased antigen uptake and upregulated major histocompatibility complex class II expression in macrophages. This indicated that the GNP can function as not only an adjuvant to promote the phagocytic activity of macrophages but also a carrier to deliver the conjugated antigen into the immune cells for the enhancement of its antigen presentation capability. Importantly, OVA-specific immunoglobulin G levels in the mice immunized with GNP-OVA were 4.1 and 2.9 times higher than those in the mice injected with OVA and GNP-PEG/OVA, respectively. These results demonstrated that the GNP-antigen conjugate exhibited remarkable stability either in liquid or freeze-dried form, which makes it attractive for further pharmaceutical applications. Moreover, covalently linking antigens onto the GNP surface was enabled to enhance the immunogenicity of antigens and boost immune responses, showing the potential of the GNP conjugation strategy for vaccine development.


Asunto(s)
Oro , Nanopartículas del Metal , Ratones , Animales , Oro/química , Nanopartículas del Metal/química , Antígenos/química , Adyuvantes Inmunológicos/química , Ovalbúmina/química , Polietilenglicoles , Inmunidad
16.
Eur J Med Chem ; 240: 114598, 2022 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-35849940

RESUMEN

Hepatocellular carcinoma (HCC) is the most common primary liver malignancy and ranks third in mortality rate worldwide. Brefeldin A (BFA, 1), a natural Arf1 inhibitor, qualifies extremely superior antitumor activity against HCC while its low aqueous solubility, poor bioavailability, and high toxicity have greatly hindered its translation to the clinic. Herein, a series of BFA-cinnamic acid ester derivatives was rationally designed and synthesized via introducing active cinnamic acid and its analogues into the structure of 1. Their in vitro cytotoxic activities on five cancer cell lines, including HepG2, BEL-7402, HeLa, Eca-109 and PANC-1, were evaluated using MTT assay. As expected, favorable cytotoxic activity was observed on majority of the mono-substituted derivatives. Especially, the most potent brefeldin A 4-O-(4)-dimethylaminocinnamate (CHNQD-01269, 33) with improved aqueous solubility, demonstrated the strong cytotoxic activity against HepG2 and BEL-7402 cell lines with IC50 values of 0.29 and 0.84 µM, respectively. More importantly, 33 performed low toxicity on normal liver cell line L-02 with the selectivity index (SI) of 9.69, which was more than 17-fold higher than that of 1. Results from mechanistic studies represented that 33 blocked the cell cycle in the G1 phase, and induced apoptosis via elevating reactive oxygen species (ROS) production and increasing expression of apoptosis-related proteins of HepG2 cells. Docking experiment also suggested 33 a promising Arf1 inhibitor, which was confirmed by the cellular thermal shift assay that 33 displayed a significant effect on the stability of Arf1 protein. Furthermore, 33 possessed high safety profile (MTD >100 mg/kg, ip) and favorable pharmacokinetic properties. Notably, the superior antiproliferative activity was verified in HepG2 tumor-bearing xenograft model in which 33 markedly suppressed the tumor growth (TGI = 46.17%) in nude mice at a dose of 10 mg/kg once a day for 16 d. The present study provided evidence of exploiting this series of highly efficacious derivatives, especially 33, for the treatment of HCC.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Antineoplásicos/química , Apoptosis , Brefeldino A/química , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Proliferación Celular , Cinamatos , Ensayos de Selección de Medicamentos Antitumorales , Ésteres/farmacología , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Ratones , Ratones Desnudos , Relación Estructura-Actividad
17.
Antiviral Res ; 203: 105347, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35643150

RESUMEN

Zika virus (ZIKV) is a flavivirus that causes severe neuropathology in newborns and adults. There is no ZIKV-specific treatment or preventative. Therefore, it is urgent to develop safe and effective anti-ZIKV agents. Hemin, an iron-binding porphyrin, has been authorized by FDA to treat acute porphyria since the 1970s. Here, we aim to evaluate the anti-ZIKV effect of hemin in SNB-19 cells (a human glioma cell line) and explore the underlying mechanism based on the virus life cycle and functions of the host cell. Our study found that hemin has a strong activity to protect SNB-19 cells from ZIKV infection presented by decreased expression of viral proteins and virus yield. Meanwhile, ZIKV infection caused STAT1/IRF1 signaling activation and induced inflammatory responses in SNB-19 cells, which was relieved by hemin treatment. HO-1 has been reported to be potently induced by hemin and play a broad-spectrum antiviral effect. Intriguingly, hemin could still exert anti-ZIKV activity upon HO-1 siRNA treatment. Then, we conducted a time-of-addition assay, the result indicated hemin works mainly by interfering with the virus entry process. Further experiments excluded the effects of hemin on AXL-dependent viral adsorption and clathrin-mediated endocytosis processes. Subsequently, by fluorescence spectroscopy studies, intracellular fusion assay and syncytia formation assay, we revealed that hemin acts on the process of virus-endosome fusion. This study elaborated that hemin could play anti-ZIKV activity by disrupting the virus-endosome fusion process and shed new light on developing novel agents against ZIKV infection.


Asunto(s)
Infección por el Virus Zika , Virus Zika , Animales , Chlorocebus aethiops , Virus ADN , Endosomas , Hemina/farmacología , Humanos , Recién Nacido , Células Vero , Internalización del Virus , Replicación Viral , Infección por el Virus Zika/metabolismo
18.
Biochem Pharmacol ; 200: 115033, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35395242

RESUMEN

As a chronic metabolic disease affecting epidemic proportions worldwide, the pathogenesis of Nonalcoholic Fatty Liver Disease (NAFLD) is not clear yet. There is also a lack of precise biomarkers and specific medicine for the diagnosis and treatment of NAFLD. Methionine metabolic cycle, which is critical for the maintaining of cellular methylation and redox state, is involved in the pathophysiology of NAFLD. However, the molecular basis and mechanism of methionine metabolism in NAFLD are not completely understood. Here, we mainly focus on specific enzymes that participates in methionine cycle, to reveal their interconnections with NAFLD, in order to recognize the pathogenesis of NAFLD from a new angle and at the same time, explore the clinical characteristics and therapeutic strategies.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Biomarcadores/metabolismo , Humanos , Hígado/metabolismo , Metionina/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Oxidación-Reducción
19.
Biochem Pharmacol ; 198: 114952, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35149050

RESUMEN

PURPOSE: Allergic asthma is a chronic inflammatory disorder with airway hyperresponsiveness and tissue remodeling as the main pathological characteristics. The etiology of asthma is relatively complicated, involving genetic susceptibility, epigenetic regulation, environmental factors, and immune imbalance. Colony stimulating factor 1 receptor (CSF-1R), highly expressed in myeloid monocytes, plays an important role in regulating inflammation. However, the pathological role of CSF-1R and the therapeutic effects of CSF-1R inhibitor in allergic airway inflammation remain indistinct. METHODS: The house dust mite (HDM)-triggered allergic airway inflammation model was conducted to fully uncover the efficacies of CSF-1R inhibition, as illustrated by histopathological examinations, biochemical analysis, ELISA, RT-PCR, Western blotting assay, immunofluorescence, and flow cytometry. Furthermore, bone marrow-derived macrophages (BMDMs) were differentiated and polarized upon IL-4/IL-13 induction to clarify the underlying mechanisms of CSF-1R inhibition. RESULTS: Herein, we presented that the expression of CSF-1R was increased in HDM-induced experimental asthma and inhibition of CSF-1R displayed dramatic effects on the disease severity of asthma, referring to suppressing the secretion of allergic mediators, dysfunction of airway epithelium, and infiltration of inflammatory cells. Furthermore, CSF-1R inhibitor could markedly restrain the polarization and expression of transcriptional factors of alternatively activated macrophages (AAMs) in the presence of IL-4/IL-13 and reduce the recruitment of CSF-1R-dominant macrophages, both in acute and chronic allergic airway inflammation model. CONCLUSION: Collectively, our findings demonstrated the molecular pathological mechanism of CSF-1R in allergic airway diseases and suggested that targeting CSF-1R might be an alternative intervention strategy on the homeostasis of airway immune microenvironment in asthma.


Asunto(s)
Asma , Hipersensibilidad , Animales , Asma/metabolismo , Modelos Animales de Enfermedad , Epigénesis Genética , Hipersensibilidad/metabolismo , Inflamación , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Pulmón/metabolismo , Macrófagos/metabolismo , Pyroglyphidae
20.
Mar Life Sci Technol ; 4(1): 88-97, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37073350

RESUMEN

Marine natural products play critical roles in the chemical defense of many marine organisms and are essential, reputable sources of successful drug leads. Sixty-seven 14-membered resorcylic acid lactone derivatives 3-27 and 30-71 of the natural product zeaenol (1) isolated from the marine-derived fungus Cochliobolus lunatus were semisynthesized by chlorination, acylation, esterification, and acetalization in one to three steps. The structures of these new derivatives were established by HRESIMS and NMR techniques. All the compounds (1-71) were evaluated for their antialgal and antiplasmodial activities. Among them, 14 compounds displayed antifouling activities against adhesion of the fouling diatoms. In particular, 9 and 34 exhibited strong and selective inhibitory effects against the diatoms Navicula laevissima and Navicula exigua (EC50 = 6.67 and 8.55 µmol/L), respectively, which were similar in efficacy to those of the positive control SeaNine 211 (EC50 = 2.90 and 9.74 µmol/L). More importantly, 38, 39, and 69-71 showed potent antiplasmodial activities against Plasmodium falciparum with IC50 values ranging from 3.54 to 9.72 µmol/L. Very interestingly, the five antiplasmodial derivatives displayed non-toxicity in the cytotoxicity assays and the zebrafish embryos model, thus, representing potential promising antiplasmodial drug agents. The preliminary structure-activity relationships indicated that biphenyl substituent at C-2, acetonide at positions C-5' and C-6', and tri- or tetra-substituted of acyl groups increased the antiplasmodial activity. Therefore, combining evaluation of chemical ecology with pharmacological models will be implemented as a systematic strategy, not only for environmentally friendly antifoulants but also for structurally novel drugs. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-021-00103-0.

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