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1.
Plant Cell ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38869214

RESUMO

Anthocyanins play critical roles in protecting plant tissues against diverse stresses. The complicated regulatory networks induced by various environmental factors modulate the homeostatic level of anthocyanins. Here, we show that anthocyanin accumulation is induced by brassinosteroids (BRs) in Arabidopsis (Arabidopsis thaliana) shoots and shed light on the underlying regulatory mechanism. We observed that anthocyanin levels are altered considerably in BR-related mutants, and BRs induce anthocyanin accumulation by up-regulating the expression of anthocyanin biosynthetic genes. Our genetic analysis indicated that BRASSINAZOLE RESISTANT 1 (BZR1) and PRODUCTION OF ANTHOCYANIN PIGMENT 1 (PAP1) are essential for BR-induced anthocyanin accumulation. The BR-responsive transcription factor BZR1 directly binds to the PAP1 promoter, regulating its expression. In addition, we found that intense anthocyanin accumulation caused by the pap1-D dominant mutation is significantly reduced in BR mutants, implying that BR activity is required for PAP1 function after PAP1 transcription. Moreover, we demonstrated that BZR1 physically interacts with PAP1 to cooperatively regulate the expression of PAP1 target genes, such as TRANSPARENT TESTA 8 (TT8), DIHYDROFLAVONOL 4-REDUCTASE (DFR), and LEUKOANTHOCYANIDIN DIOXYGENASE (LDOX). Our findings indicate that BZR1 functions as an integral component of the PAP1-containing transcription factor complex, contributing to increased anthocyanin biosynthesis. Notably, we also show that functional interaction of BZR1 with PAP1 is required for anthocyanin accumulation induced by low nitrogen stress. Taken together, our results demonstrate that BR-regulated BZR1 promotes anthocyanin biosynthesis through cooperative interaction with PAP1 of the MBW complex.

2.
Nucleic Acids Res ; 52(14): 8063-8071, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-38917331

RESUMO

Enabling the precise control of protein functions with artificially programmed reaction patterns is beneficial for investigating biological processes. Although several strategies have been established that employ the programmability of nucleic acid, they have been limited to DNA hybridization without external stimuli or target binding. Here, we report an approach for the DNA-mediated control of the tripartite split-GFP assembly via aptamers with responsiveness to intracellular small molecules as stimuli. We designed a novel structure-switching aptamer-peptide conjugate as a hetero modulator for split GFP in response to ATP. By conjugating two peptides (S10/11) derived from the tripartite split-GFP to ATP aptamer, we achieved GFP reassembly using only ATP as a trigger molecule. The response to ATP at ≥4 mM concentrations indicated that it can be applied to respond to intracellular ATP in live cells. Furthermore, our hetero-modulator exhibited high and long-term stability, with a half-life of approximately four days in a serum stability assay, demonstrating resistance to nuclease degradation. We validated that our aptamer-modulator split GFP was successfully reconstituted in the cell in response to intracellular ATP levels. Our aptamer-modulated split GFP platform can be utilized to monitor a wide range of intracellular metabolites by replacing the aptamer sequence.


Assuntos
Trifosfato de Adenosina , Aptâmeros de Nucleotídeos , Proteínas de Fluorescência Verde , Peptídeos , Trifosfato de Adenosina/metabolismo , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Fluorescência Verde/genética , Humanos , Peptídeos/química , Peptídeos/metabolismo , DNA/química , DNA/metabolismo , Fluorescência , Células HeLa
3.
Brief Bioinform ; 25(1)2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-38180831

RESUMO

The enzyme-linked immunosorbent spot (ELISpot) assay is a powerful in vitro immunoassay that enables cost-effective quantification of antigen-specific T-cell reactivity. It is used widely in the context of cancer and infectious diseases to validate the immunogenicity of predicted epitopes. While technological advances have kept pace with the demand for increased throughput, efforts to increase scale are bottlenecked by current assay design and deconvolution methods, which have remained largely unchanged. Current methods for designing pooled ELISpot experiments offer limited flexibility of assay parameters, lack support for high-throughput scenarios and do not consider peptide identity during pool assignment. We introduce the ACE Configurator for ELISpot (ACE) to address these gaps. ACE generates optimized peptide-pool assignments from highly customizable user inputs and handles the deconvolution of positive peptides using assay readouts. In this study, we present a novel sequence-aware pooling strategy, powered by a fine-tuned ESM-2 model that groups immunologically similar peptides, reducing the number of false positives and subsequent confirmatory assays compared to existing combinatorial approaches. To validate ACE's performance on real-world datasets, we conducted a comprehensive benchmark study, contextualizing design choices with their impact on prediction quality. Our results demonstrate ACE's capacity to further increase precision of identified immunogenic peptides, directly optimizing experimental efficiency. ACE is freely available as an executable with a graphical user interface and command-line interfaces at https://github.com/pirl-unc/ace.


Assuntos
Benchmarking , Imunoadsorventes , Epitopos , Peptídeos
4.
Nat Mater ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39060469

RESUMO

Conducting polymers are mixed ionic-electronic conductors that are emerging candidates for neuromorphic computing, bioelectronics and thermoelectrics. However, fundamental aspects of their many-body correlated electron-ion transport physics remain poorly understood. Here we show that in p-type organic electrochemical transistors it is possible to remove all of the electrons from the valence band and even access deeper bands without degradation. By adding a second, field-effect gate electrode, additional electrons or holes can be injected at set doping states. Under conditions where the counterions are unable to equilibrate in response to field-induced changes in the electronic carrier density, we observe surprising, non-equilibrium transport signatures that provide unique insights into the interaction-driven formation of a frozen, soft Coulomb gap in the density of states. Our work identifies new strategies for substantially enhancing the transport properties of conducting polymers by exploiting non-equilibrium states in the coupled system of electronic charges and counterions.

5.
Ann Intern Med ; 177(3): 291-302, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38437702

RESUMO

BACKGROUND: Some data suggest a higher incidence of diagnosis of autoimmune inflammatory rheumatic diseases (AIRDs) among patients with a history of COVID-19 compared with uninfected patients. However, these studies had methodological shortcomings. OBJECTIVE: To investigate the effect of COVID-19 on long-term risk for incident AIRD over various follow-up periods. DESIGN: Binational, longitudinal, propensity-matched cohort study. SETTING: Nationwide claims-based databases in South Korea (K-COV-N cohort) and Japan (JMDC cohort). PARTICIPANTS: 10 027 506 Korean and 12 218 680 Japanese patients aged 20 years or older, including those with COVID-19 between 1 January 2020 and 31 December 2021, matched to patients with influenza infection and to uninfected control patients. MEASUREMENTS: The primary outcome was onset of AIRD (per appropriate codes from the International Classification of Diseases, 10th Revision) 1, 6, and 12 months after COVID-19 or influenza infection or the respective matched index date of uninfected control patients. RESULTS: Between 2020 and 2021, among the 10 027 506 Korean participants (mean age, 48.4 years [SD, 13.4]; 50.1% men), 394 274 (3.9%) and 98 596 (0.98%) had a history of COVID-19 or influenza, respectively. After propensity score matching, beyond the first 30 days after infection, patients with COVID-19 were at increased risk for incident AIRD compared with uninfected patients (adjusted hazard ratio, 1.25 [95% CI, 1.18 to 1.31]) and influenza-infected control patients (adjusted hazard ratio, 1.30 [CI, 1.02 to 1.59]). The risk for incident AIRD was higher with more severe acute COVID-19. Similar patterns were observed in the Japanese cohort. LIMITATIONS: Referral bias due to the pandemic; residual confounding. CONCLUSION: SARS-CoV-2 infection was associated with increased risk for incident AIRD compared with matched patients without SARS-CoV-2 infection or with influenza infection. The risk for incident AIRD was higher with greater severity of acute COVID-19. PRIMARY FUNDING SOURCE: National Research Foundation of Korea.


Assuntos
COVID-19 , Influenza Humana , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , COVID-19/epidemiologia , Estudos de Coortes , SARS-CoV-2 , Estudos Longitudinais
6.
Chem Soc Rev ; 53(9): 4674-4706, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38529583

RESUMO

High power conversion efficiency (PCE) and long-term stability are essential prerequisites for the commercialization of polymer solar cells (PSCs). Small-molecule acceptors (SMAs) are core materials that have led to recent, rapid increases in the PCEs of the PSCs. However, a critical limitation of the resulting PSCs is their poor long-term stability. Blend morphology degradation from rapid diffusion of SMAs with low glass transition temperatures (Tgs) is considered the main cause of the poor long-term stability of the PSCs. The recent emergence of oligomerized SMAs (OSMAs), composed of two or more repeating SMA units (i.e., dimerized and trimerized SMAs), has shown great promise in overcoming these challenges. This innovation in material design has enabled OSMA-based PSCs to reach impressive PCEs near 19% and exceptional long-term stability. In this review, we summarize the evolution of OSMAs, including their research background and recent progress in molecular design. In particular, we discuss the mechanisms for high PCE and stability of OSMA-based PSCs and suggest useful design guidelines for high-performance OSMAs. Furthermore, we reflect on the existing hurdles and future directions for OSMA materials towards achieving commercially viable PSCs with high PCEs and operational stabilities.

7.
Nano Lett ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619226

RESUMO

Halide perovskite-based resistive switching memory (memristor) has potential in an artificial synapse. However, an abrupt switch behavior observed for a formamidinium lead triiodide (FAPbI3)-based memristor is undesirable for an artificial synapse. Here, we report on the δ-FAPbI3/atomic-layer-deposited (ALD)-SnO2 bilayer memristor for gradual analogue resistive switching. In comparison to a single-layer δ-FAPbI3 memristor, the heterojunction δ-FAPbI3/ALD-SnO2 bilayer effectively reduces the current level in the high-resistance state. The analog resistive switching characteristics of δ-FAPbI3/ALD-SnO2 demonstrate exceptional linearity and potentiation/depression performance, resembling an artificial synapse for neuromorphic computing. The nonlinearity of long-term potentiation and long-term depression is notably decreased from 12.26 to 0.60 and from -8.79 to -3.47, respectively. Moreover, the δ-FAPbI3/ALD-SnO2 bilayer achieves a recognition rate of ≤94.04% based on the modified National Institute of Standards and Technology database (MNIST), establishing its potential in an efficient artificial synapse.

8.
Nano Lett ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856974

RESUMO

In this study, we examined the nanostructured molecular packing and orientations of poly[[N,N'-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5'-(2,2'-bithiophene)] (P(NDI2OD-T2)) films formed on water for the application of nanotechnology-based organic electronic devices. First, the nanoscale molecule-substrate interaction between the polymer and water was modulated by controlling the alkyl side chain length in NDI-based copolymers. Increasing alkyl side chain lengths induced a nanomorphological transition from face-on to edge-on orientation, confirmed by molecular dynamics simulations revealing nanostructural behavior. Second, the nanoscale intermolecular interactions of P(NDI2OD-T2) were controlled by varying the volume ratio of the high-boiling-point additive solvent in the binary solvent blends. As the additive solvent ratio increased, the nanostructured molecular orientation of the P(NDI2OD-T2) films on water changed remarkably from edge-on to bimodal with more face-on crystallites, thereby affecting charge transport. Our finding provides essential insights for precise nanoscale morphological control on water substrates, enabling the formation of high-performance polymer films for organic electronic devices.

9.
Nano Lett ; 24(30): 9322-9330, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-38924488

RESUMO

Electrochemical CO2 reduction reaction (eCO2RR) over Cu-based catalysts is a promising approach for efficiently converting CO2 into value-added chemicals and alternative fuels. However, achieving controllable product selectivity from eCO2RR remains challenging because of the difficulty in controlling the oxidation states of Cu against robust structural reconstructions during the eCO2RR. Herein, we report a novel strategy for tuning the oxidation states of Cu species and achieving eCO2RR product selectivity by adjusting the Cu content in CuMgAl-layered double hydroxide (LDH)-based catalysts. In this strategy, the highly stable Cu2+ species in low-Cu-containing LDHs facilitated the strong adsorption of *CO intermediates and further hydrogenation into CH4. Conversely, the mixed Cu0/Cu+ species in high-Cu-containing LDHs derived from the electroreduction during the eCO2RR accelerated C-C coupling reactions. This strategy to regulate Cu oxidation states using LDH nanostructures with low and high Cu molar ratios produced an excellent eCO2RR performance for CH4 and C2+ products, respectively.

10.
BMC Bioinformatics ; 25(1): 236, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997639

RESUMO

BACKGROUND: Homologous recombination deficiency (HRD) stands as a clinical indicator for discerning responsive outcomes to platinum-based chemotherapy and poly ADP-ribose polymerase (PARP) inhibitors. One of the conventional approaches to HRD prognostication has generally centered on identifying deleterious mutations within the BRCA1/2 genes, along with quantifying the genomic scars, such as Genomic Instability Score (GIS) estimation with scarHRD. However, the scarHRD method has limitations in scenarios involving tumors bereft of corresponding germline data. Although several RNA-seq-based HRD prediction algorithms have been developed, they mainly support cohort-wise classification, thereby yielding HRD status without furnishing an analogous quantitative metric akin to scarHRD. This study introduces the expHRD method, which operates as a novel transcriptome-based framework tailored to n-of-1-style HRD scoring. RESULTS: The prediction model has been established using the elastic net regression method in the Cancer Genome Atlas (TCGA) pan-cancer training set. The bootstrap technique derived the HRD geneset for applying the expHRD calculation. The expHRD demonstrated a notable correlation with scarHRD and superior performance in predicting HRD-high samples. We also performed intra- and extra-cohort evaluations for clinical feasibility in the TCGA-OV and the Genomic Data Commons (GDC) ovarian cancer cohort, respectively. The innovative web service designed for ease of use is poised to extend the realms of HRD prediction across diverse malignancies, with ovarian cancer standing as an emblematic example. CONCLUSIONS: Our novel approach leverages the transcriptome data, enabling the prediction of HRD status with remarkable precision. This innovative method addresses the challenges associated with limited available data, opening new avenues for utilizing transcriptomics to inform clinical decisions.


Assuntos
Recombinação Homóloga , Neoplasias , Transcriptoma , Humanos , Transcriptoma/genética , Recombinação Homóloga/genética , Neoplasias/genética , Algoritmos , Feminino , Perfilação da Expressão Gênica/métodos
11.
Stroke ; 55(3): e61-e76, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38235581

RESUMO

Accumulating evidence supports a link between sleep disorders, disturbed sleep, and adverse brain health, ranging from stroke to subclinical cerebrovascular disease to cognitive outcomes, including the development of Alzheimer disease and Alzheimer disease-related dementias. Sleep disorders such as sleep-disordered breathing (eg, obstructive sleep apnea), and other sleep disturbances, as well, some of which are also considered sleep disorders (eg, insomnia, sleep fragmentation, circadian rhythm disorders, and extreme sleep duration), have been associated with adverse brain health. Understanding the causal role of sleep disorders and disturbances in the development of adverse brain health is complicated by the common development of sleep disorders among individuals with neurodegenerative disease. In addition to the role of sleep disorders in stroke and cerebrovascular injury, mechanistic hypotheses linking sleep with brain health and biomarker data (blood-based, cerebrospinal fluid-based, and imaging) suggest direct links to Alzheimer disease-specific pathology. These potential mechanisms and the increasing understanding of the "glymphatic system," and the recognition of the importance of sleep in poststroke recovery, as well, support a biological basis for the indirect (through the worsening of vascular disease) and direct (through specific effects on neuropathology) connections between sleep disorders and brain health. Given promising evidence for the benefits of treatment and prevention, sleep disorders and disturbances represent potential targets for early treatment that may improve brain health more broadly. In this scientific statement, we discuss the evidence supporting an association between sleep disorders and disturbances and poor brain health ranging from stroke to dementia and opportunities for prevention and early treatment.


Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Transtornos do Sono-Vigília , Acidente Vascular Cerebral , Humanos , Doença de Alzheimer/complicações , American Heart Association , Sono , Encéfalo/patologia , Acidente Vascular Cerebral/complicações , Transtornos do Sono-Vigília/complicações
12.
J Am Chem Soc ; 146(32): 22387-22395, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39088737

RESUMO

Preventing ion migration in perovskite photovoltaics is key to achieving stable and efficient devices. The activation energy for ion migration is affected by the chemical environment surrounding the ions. Thus, the migration of organic cations in lead halide perovskites can be mitigated by engineering their local interactions, for example through hydrogen bonding. Ion migration also leads to ionic losses via interfacial reactions. Undesirable reactivities of the organic cations can be eliminated by introducing protecting groups. In this work, we report bis(2-oxo-3-oxazolidinyl) phosphinic chloride (BOP-Cl) as a perovskite ink additive with the following benefits: (1) The phosphoryl and two oxo groups form six-membered intermolecular hydrogen-bonded rings with the formamidinium cation (FA), mitigating ion migrations. (2) The hydrogen bonding reduces the electrophilicity of the ammonium protons by donating electron density, therefore reducing its reactivity with the surface oxygen on the metal oxide. Furthermore, the molecule can react to form a protecting group on the nucleophilic oxygen at the tin oxide transport layer surface through the elimination of chlorine. As a result, we achieve perovskite solar cells with an efficiency of 25.0% and improved MPP stability T93 = 1200 h at 40-45 °C compared to a control device (T86 = 550 h). In addition, we show a negative correlation between the strength of hydrogen bonding of different phosphine oxide derivatives to the organic cations and the degree of metastable behavior (e.g., initial burn-in) of the device.

13.
J Am Chem Soc ; 146(28): 19434-19448, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38959476

RESUMO

Immuno-photodynamic therapy (IPDT) has emerged as a new modality for cancer treatment. Novel photosensitizers can help achieve the promise inherent in IPDT, namely, the complete eradication of a tumor without recurrence. We report here a small molecule photosensitizer conjugate, LuCXB. This IPDT agent integrates a celecoxib (cyclooxygenase-2 inhibitor) moiety with a near-infrared absorbing lutetium texaphyrin photocatalytic core. In aqueous environments, the two components of LuCXB are self-associated through inferred donor-acceptor interactions. A consequence of this intramolecular association is that upon photoirradiation with 730 nm light, LuCXB produces superoxide radicals (O2-•) via a type I photodynamic pathway; this provides a first line of defense against the tumor while promoting IPDT. For in vivo therapeutic applications, we prepared a CD133-targeting, aptamer-functionalized exosome-based nanophotosensitizer (Ex-apt@LuCXB) designed to target cancer stem cells. Ex-apt@LuCXB was found to display good photosensitivity, acceptable biocompatibility, and robust tumor targetability. Under conditions of photoirradiation, Ex-apt@LuCXB acts to amplify IPDT while exerting a significant antitumor effect in both liver and breast cancer mouse models. The observed therapeutic effects are attributed to a synergistic mechanism that combines antiangiogenesis and photoinduced cancer immunotherapy.


Assuntos
Celecoxib , Lutécio , Fotoquimioterapia , Fármacos Fotossensibilizantes , Porfirinas , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Animais , Humanos , Porfirinas/química , Porfirinas/farmacologia , Camundongos , Lutécio/química , Celecoxib/química , Celecoxib/farmacologia , Imunoterapia , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Antineoplásicos/química , Feminino
14.
Curr Issues Mol Biol ; 46(1): 513-526, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38248335

RESUMO

The process of skin aging is intricate, involving intrinsic aging, influenced by internal factors, and extrinsic aging, mainly caused by exposure to UV radiation, resulting in photoaging. Photoaging manifests as skin issues such as wrinkles and discoloration. The skin microbiome, a diverse community of microorganisms on the skin's surface, plays a crucial role in skin protection and can be affected by factors like humidity and pH. Probiotics, beneficial microorganisms, have been investigated for their potential to enhance skin health by regulating the skin microbiome. This can be accomplished through oral probiotics, impacting the gut-skin axis, or topical applications introducing live bacteria to the skin. Probiotics mitigate oxidative stress, suppress inflammation, and maintain the skin's extracellular matrix, ultimately averting skin aging. However, research on probiotics derived from human skin is limited, and there is no established product for preventing photoaging. The mechanism by which probiotics shield the skin microbiome and skin layers from UV radiation remains unclear. Recently, researchers have discovered Lactobacillus in the skin, with reports indicating a decrease in this microorganism with age. In a recent study, scientists isolated Lactobacillus iners KOLBM20 from the skin of individuals in their twenties and confirmed its effectiveness. A comparative analysis of genetic sequences revealed that strain KOLBM20 belongs to the Lactobacillus genus and closely relates to L. iners DSM13335(T) with a 99.20% similarity. Importantly, Lactobacillus iners KOLBM20 displayed anti-wrinkle properties by inhibiting MMP-1. This investigation demonstrated the inhibitory effect of KOLBM20 strain lysate on MMP-1 expression. Moreover, the data suggest that KOLBM20 strain lysate may prevent UVB-induced MMP-1 expression by inhibiting the activation of the ERK, JNK, and p38 signaling pathways induced by UVB. Consequently, KOLBM20 strain lysate holds promise as a potential therapeutic agent for preventing and treating skin photoaging.

15.
Nat Prod Rep ; 41(8): 1294-1317, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-38916377

RESUMO

Covering: up to December 2023Decalin-containing tetramic acid derivatives, especially 3-decalinoyltetramic acids (3-DTAs), are commonly found as fungal secondary metabolites. Numerous biological activities of this class of compounds, such as antibiotic, antiviral, antifungal, antiplasmodial, and antiprotozoal properties, have been the subject of ongoing research. For this reason, these molecules have attracted a lot of interest from the scientific community and various efforts including semi-synthesis, co-culturing with bacteria and biosynthetic gene sequencing have been made to obtain more derivatives. In this review, 3-DTAs are classified into four major groups based on the absolute configuration of the bicyclic decalin ring. Their biosynthetic pathways, various biological activities, and structure-activity relationship are then introduced.


Assuntos
Fungos , Pirrolidinonas , Relação Estrutura-Atividade , Fungos/química , Fungos/metabolismo , Pirrolidinonas/farmacologia , Pirrolidinonas/química , Pirrolidinonas/isolamento & purificação , Pirrolidinonas/metabolismo , Estrutura Molecular , Naftalenos/farmacologia , Naftalenos/química , Naftalenos/isolamento & purificação , Naftalenos/metabolismo , Antifúngicos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/biossíntese , Antibacterianos/isolamento & purificação
16.
Nat Prod Rep ; 41(8): 1318, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-38984501

RESUMO

Correction for 'Biosynthesis, biological activities, and structure-activity relationships of decalin-containing tetramic acid derivatives isolated from fungi' by Hyun Woo Kim et al., Nat. Prod. Rep., 2024, https://doi.org/10.1039/d4np00013g.

17.
Antimicrob Agents Chemother ; 68(4): e0095623, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38446062

RESUMO

Viral RNA-dependent RNA polymerase (RdRp), a highly conserved molecule in RNA viruses, has recently emerged as a promising drug target for broad-acting inhibitors. Through a Vero E6-based anti-cytopathic effect assay, we found that BPR3P0128, which incorporates a quinoline core similar to hydroxychloroquine, outperformed the adenosine analog remdesivir in inhibiting RdRp activity (EC50 = 0.66 µM and 3 µM, respectively). BPR3P0128 demonstrated broad-spectrum activity against various severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern. When introduced after viral adsorption, BPR3P0128 significantly decreased SARS-CoV-2 replication; however, it did not affect the early entry stage, as evidenced by a time-of-drug-addition assay. This suggests that BPR3P0128's primary action takes place during viral replication. We also found that BPR3P0128 effectively reduced the expression of proinflammatory cytokines in human lung epithelial Calu-3 cells infected with SARS-CoV-2. Molecular docking analysis showed that BPR3P0128 targets the RdRp channel, inhibiting substrate entry, which implies it operates differently-but complementary-with remdesivir. Utilizing an optimized cell-based minigenome RdRp reporter assay, we confirmed that BPR3P0128 exhibited potent inhibitory activity. However, an enzyme-based RdRp assay employing purified recombinant nsp12/nsp7/nsp8 failed to corroborate this inhibitory activity. This suggests that BPR3P0128 may inhibit activity by targeting host-related RdRp-associated factors. Moreover, we discovered that a combination of BPR3P0128 and remdesivir had a synergistic effect-a result likely due to both drugs interacting with separate domains of the RdRp. This novel synergy between the two drugs reinforces the potential clinical value of the BPR3P0128-remdesivir combination in combating various SARS-CoV-2 variants of concern.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , COVID-19 , Pirazóis , Quinolinas , Humanos , SARS-CoV-2/metabolismo , RNA Polimerase Dependente de RNA/metabolismo , Simulação de Acoplamento Molecular , Tratamento Farmacológico da COVID-19 , Antivirais/química
18.
Biochem Biophys Res Commun ; 721: 150108, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38762931

RESUMO

Drug-tolerant persister (DTP) cells remain following chemotherapy and can cause cancer relapse. However, it is unclear when acquired resistance to chemotherapy emerges. Here, we compared the gene expression profiles of gastric cancer patient-derived cells (GC PDCs) and their respective xenograft tumors with different sensitivities to 5-fluorouracil (5-FU) by using immunodeficient female BALB/c-nu mice. RNA sequencing analysis of 5-FU-treated PDCs demonstrated that DNA replication/cell cycle-related genes were transiently induced in the earlier phase of DTP cell emergence, while extracellular matrix (ECM)-related genes were sustainably upregulated during long-term cell survival in 5-FU-resistant residual tumors. NicheNet analysis, which uncovers cell-cell signal interactions, indicated the transforming growth factor-ß (TGF-ß) pathway as the upstream regulator in response to 5-FU treatment. This induced ECM-related gene expression in the 5-FU-resistant tumor model. In the 5-FU-resistant residual tumors, there was a marked upregulation of cancer cell-derived TGF-ß1 expression and increased phosphorylation of SMAD3, a downstream regulator of the TGF-ß receptor. By contrast, these responses were not observed in a 5-FU-sensitive tumor model. We further found that TGF-ß-related upregulation of ECM genes was preferentially observed in non-responders to chemotherapy with 5-FU and/or oxaliplatin among 22 patient-derived xenograft tumors. These observations suggest that chemotherapy-induced activation of the TGF-ß1/SMAD3/ECM-related gene axis is a potential biomarker for the emergence of drug resistance in GCs.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Matriz Extracelular , Fluoruracila , Regulação Neoplásica da Expressão Gênica , Camundongos Endogâmicos BALB C , Transdução de Sinais , Neoplasias Gástricas , Fator de Crescimento Transformador beta , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Humanos , Animais , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Feminino , Transdução de Sinais/efeitos dos fármacos , Matriz Extracelular/metabolismo , Matriz Extracelular/efeitos dos fármacos , Camundongos , Fator de Crescimento Transformador beta/metabolismo , Camundongos Nus , Linhagem Celular Tumoral , Proteína Smad3/metabolismo , Proteína Smad3/genética , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Eur Respir J ; 63(5)2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38359963

RESUMO

BACKGROUND: We previously identified ezetimibe, an inhibitor of Niemann-Pick C1-like intracellular cholesterol transporter 1 and European Medicines Agency-approved lipid-lowering agent, as a potent autophagy activator. However, its efficacy against pulmonary fibrosis has not yet been evaluated. This study aimed to determine whether ezetimibe has therapeutic potential against idiopathic pulmonary fibrosis. METHODS: Primary lung fibroblasts isolated from both humans and mice were employed for mechanistic in vitro experiments. mRNA sequencing of human lung fibroblasts and gene set enrichment analysis were performed to explore the therapeutic mechanism of ezetimibe. A bleomycin-induced pulmonary fibrosis mouse model was used to examine in vivo efficacy of the drug. Tandem fluorescent-tagged microtubule-associated protein 1 light chain 3 transgenic mice were used to measure autophagic flux. Finally, the medical records of patients with idiopathic pulmonary fibrosis from three different hospitals were reviewed retrospectively, and analyses on survival and lung function were conducted to determine the benefits of ezetimibe. RESULTS: Ezetimibe inhibited myofibroblast differentiation by restoring the mechanistic target of rapamycin complex 1-autophagy axis with fine control of intracellular cholesterol distribution. Serum response factor, a potential autophagic substrate, was identified as a primary downstream effector in this process. Similarly, ezetimibe ameliorated bleomycin-induced pulmonary fibrosis in mice by inhibiting mechanistic target of rapamycin complex 1 activity and increasing autophagic flux, as observed in mouse lung samples. Patients with idiopathic pulmonary fibrosis who regularly used ezetimibe showed decreased rates of all-cause mortality and lung function decline. CONCLUSION: Our study presents ezetimibe as a potential novel therapeutic for idiopathic pulmonary fibrosis.


Assuntos
Anticolesterolemiantes , Autofagia , Modelos Animais de Doenças , Reposicionamento de Medicamentos , Ezetimiba , Fibrose Pulmonar Idiopática , Ezetimiba/uso terapêutico , Ezetimiba/farmacologia , Animais , Fibrose Pulmonar Idiopática/tratamento farmacológico , Humanos , Camundongos , Autofagia/efeitos dos fármacos , Masculino , Anticolesterolemiantes/uso terapêutico , Anticolesterolemiantes/farmacologia , Feminino , Camundongos Transgênicos , Bleomicina , Pulmão/patologia , Pulmão/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/efeitos dos fármacos , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Camundongos Endogâmicos C57BL , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Colesterol/metabolismo
20.
Small ; : e2400333, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528427

RESUMO

Redox-active organic compounds gather significant attention for their potential application as electrodes in alkali ion batteries, owing to the structural versatility, environmental friendliness, and cost-effectiveness. However, their practical applications of such compounds are impeded by insufficient active sites with limited capacity, dissolution in electrolytes, and sluggish kinetics. To address these issues, a naphthol group-containing triarylamine polymer, namely poly[6,6'-(phenylazanediyl)bis(naphthol)] (poly(DNap-OH)) is rationally designed and synthesized, via oxidative coupling polymerization. It is capable of endowing favorable steric structures that facilitate fast ion diffusion, excellent chemical stability in organic electrolytes, and additional redox-active sites that enable a bipolar redox reaction. By exploiting these advantages, poly(DNap-OH) cathodes demonstrate remarkable cycling stability in both lithium-ion batteries (LIBs) and potassium-ion batteries (PIBs), showcasing enhanced specific capacity and redox reaction kinetics in comparison to the conventional poly(4-methyltriphenylamine) cathodes. Overall, this work offers insights into molecular design strategies for the development of high-performance organic cathodes in alkali-ion batteries.

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