Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
1.
Sensors (Basel) ; 23(3)2023 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-36772534

RESUMO

Integrated sensing and communications (ISAC) is emerging as a key technology of 6G. Owing to the low peak-to-average power ratio (PAPR) property, discrete Fourier transform spread orthogonal frequency-division multiplexing (DFT-s-OFDM) is helpful to improve the sensing range and suitable for high-frequency transmission. However, compared to orthogonal frequency-division multiplexing (OFDM), the sensing accuracy of DFT-s-OFDM is relatively poor. In this paper, frequency-domain spectral shaping (FDSS) is adopted to enhance the performances of DFT-s-OFDM including sensing accuracy and PAPR by adjusting the correlation of signals. Specifically, we first establish a signal model for the ISAC system, followed by the description of performance indicators. Then, we analyze the influence of amplitude fluctuation of frequency domain signals on sensing performance, which shows the design idea of FDSS-enhanced DFT-s-OFDM. Further, a FDSS-enhanced DFT-s-OFDM framework is introduced for ISAC, where two types of FDSS filters including a pre-equalization filter and an isotropic orthogonal transform algorithm (IOTA) filter are designed. The simulation results show that the proposed scheme can obtain about 4 dB performance gain in terms of sensing accuracy over DFT-s-OFDM. In addition, FDSS-enhanced DFT-s-OFDM can significantly reduce PAPR and improve the power amplifier efficiency.

2.
Sensors (Basel) ; 22(13)2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35808399

RESUMO

High frequency wireless communication aims to provide ultra high-speed transmissions for various application scenarios. The waveform design for high frequency communication is challenging due to the requirements for high spectrum efficiency, as well as good hardware compatibility. With high flexibility and low peak-to-average power ratio (PAPR), discrete Fourier transformation spreading-based orthogonal frequency division multiplexing (DFT-s-OFDM) can be a promising candidate waveform. To further enhance the spectral efficiency, we integrate faster-than-Nyquist (FTN) signaling in DFT-s-OFDM, and find that the PAPR performance can also be improved. While FTN can introduce increased inter-symbol interference (ISI), in this paper, we deploy an isotropic orthogonal transform algorithm (IOTA) filter for FTN-enhanced DFT-s-OFDM, where the compact time-frequency structure of the IOTA filter can significantly reduce the ISI. Simulation results show that the proposed waveform is capable of achieving good performance in PAPR, bit error rate (BER) and throughput, simultaneously, with 3.5 dB gain in PAPR and 50% gain in throughput.

3.
BMC Plant Biol ; 21(1): 514, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34736393

RESUMO

BACKGROUND: Coleorhiza hairs, are sheath-like outgrowth organs in the seeds of Poaceae family that look like root hair but develop from the coleorhiza epidermal cells during seed imbibition. The major role of coleorhiza hair in seed germination involves facilitating water uptake and nutrient supply for seed germination. However, molecular basis of coleorhiza hair development and underlying genes and metabolic pathways during seed germination are largely unknown and need to be established. RESULTS: In this study, a comparative transcriptome analysis of coleorhiza hairs from japonica and indica rice suggested that DEGs in embryo samples from seeds with embryo in air (EIA) as compared to embryo from seeds completely covered by water (CBW) were enriched in water deprivation, abscisic acid (ABA) and auxin metabolism, carbohydrate catabolism and phosphorus metabolism in coleorhiza hairs in both cultivars. Up-regulation of key metabolic genes in ABA, auxin and dehydrin and aquaporin genes may help maintain the basic development of coleorhiza hair in japonica and indica in EIA samples during both early and late stages. Additionally, DEGs involved in glutathione metabolism and carbon metabolism are upregulated while DEGs involved in amino acid and nucleotide sugar metabolism are downregulated in EIA suggesting induction of oxidative stress-alleviating genes and less priority to primary metabolism. CONCLUSIONS: Taken together, results in this study could provide novel aspects about the molecular signaling that could be involved in coleorhiza hair development in different types of rice cultivars during seed germination and may give some hints for breeders to improve seed germination efficiency under moderate drought conditions.


Assuntos
Oryza/metabolismo , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas/fisiologia , Germinação/fisiologia , Ácidos Indolacéticos/metabolismo , Oryza/genética , Transcriptoma/genética
4.
Plant Physiol ; 182(3): 1510-1526, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31857423

RESUMO

Rice (Oryza sativa) molecular breeding has gained considerable attention in recent years, but inaccurate genome annotation hampers its progress and functional studies of the rice genome. In this study, we applied single-molecule long-read RNA sequencing (lrRNA_seq)-based proteogenomics to reveal the complexity of the rice transcriptome and its coding abilities. Surprisingly, approximately 60% of loci identified by lrRNA_seq are associated with natural antisense transcripts (NATs). The high-density genomic arrangement of NAT genes suggests their potential roles in the multifaceted control of gene expression. In addition, a large number of fusion and intergenic transcripts have been observed. Furthermore, 906,456 transcript isoforms were identified, and 72.9% of the genes can generate splicing isoforms. A total of 706,075 posttranscriptional events were subsequently categorized into 10 subtypes, demonstrating the interdependence of posttranscriptional mechanisms that contribute to transcriptome diversity. Parallel short-read RNA sequencing indicated that lrRNA_seq has a superior capacity for the identification of longer transcripts. In addition, over 190,000 unique peptides belonging to 9,706 proteoforms/protein groups were identified, expanding the diversity of the rice proteome. Our findings indicate that the genome organization, transcriptome diversity, and coding potential of the rice transcriptome are far more complex than previously anticipated.


Assuntos
Oryza/genética , Oryza/metabolismo , Proteogenômica/métodos , Proteoma/metabolismo , RNA Antissenso/genética , Análise de Sequência de RNA , Transcriptoma
5.
Surg Innov ; 28(4): 419-426, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33275087

RESUMO

Introduction. Complex anal fistula (CAF) is a challenging anorectal condition. Although numerous treatments for its management have been proposed, none is ideal. Herein, we investigated the clinical efficacy of video-assisted modified ligation of the intersphincteric fistula tract (LIFT) in comparison with the incision-thread-drawing procedure for Parks type II anal fistulas. Methods. Male and female adult patients with Parks type II anal fistula who were randomized to receive one of two procedures in the Anorectal Surgery Unit of the Affiliated People's Hospital of Ningbo University: video-assisted modified LIFT (test group, 30 cases) or incision thread drawing (control group, 30 cases). Healing and recurrence, postoperative pain, and postoperative autonomous anal control ability were compared. Results. In the test group, the pain scores were significantly lower (P = .001) and wound healing was faster (P = .001). However, there were no marked differences between groups in operative efficacy or postoperative infection rate (all P > .05). We followed all the patients for more than 18 months, with the test group having lower Jorge-Wexner incontinence (P = .005) and fecal incontinence (FI) severity index (P = .000) scores. No significant difference in recurrence (χ2 = .351, P = .554) or healing (χ2 = 1.071, P = .301) rate was found between the 2 groups. Conclusions. We established that video-assisted modified LIFT is superior in repairing Parks type II anal fistulas, with less trauma, quicker recovery, and better anal function.


Assuntos
Incontinência Fecal , Fístula Retal , Adulto , Canal Anal , Feminino , Humanos , Ligadura , Masculino , Fístula Retal/cirurgia , Recidiva , Resultado do Tratamento
6.
Plant J ; 94(4): 612-625, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29495079

RESUMO

Rice (Oryza sativa L.) has two ecotypes, upland and lowland rice, that have been observed to show different tolerance levels under flooding stress. In this study, two rice cultivars, upland (Up221, flooding-intolerant) and lowland (Low88, flooding-tolerant), were initially used to study their molecular mechanisms in response to flooding germination. We observed that variations in the OsCBL10 promoter sequences in these two cultivars might contribute to this divergence in flooding tolerance. Further analysis using another eight rice cultivars revealed that the OsCBL10 promoter could be classified as either a flooding-tolerant type (T-type) or a flooding-intolerant type (I-type). The OsCBL10 T-type promoter only existed in japonica lowland cultivars, whereas the OsCBL10 I-type promoter existed in japonica upland, indica upland and indica lowland cultivars. Flooding-tolerant rice cultivars containing the OsCBL10 T-type promoter have shown lower Ca2+ flow and higher α-amylase activities in comparison to those in flooding-intolerant cultivars. Furthermore, the OsCBL10 overexpression lines were sensitive to both flooding and hypoxic treatments during rice germination with enhanced Ca2+ flow in comparison to wild-type. Subsequent findings also indicate that OsCBL10 may affect OsCIPK15 protein abundance and its downstream pathways. In summary, our results suggest that the adaptation to flooding stress during rice germination is associated with two different OsCBL10 promoters, which in turn affect OsCBL10 expression in different cultivars and negatively affect OsCIPK15 protein accumulation and its downstream cascade.


Assuntos
Adaptação Fisiológica , Calcineurina/metabolismo , Cálcio/metabolismo , Oryza/genética , Regiões Promotoras Genéticas/genética , Calcineurina/genética , Ecótipo , Inundações , Variação Genética , Germinação , Oryza/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Sementes/genética , Sementes/fisiologia , Especificidade da Espécie , Estresse Fisiológico
7.
BMC Plant Biol ; 19(1): 445, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31651235

RESUMO

BACKGROUND: Apple is one of the most popular fruit crops world-wide and its skin color is an important quality consideration essential for commercial value. However, the strategy on genetic breeding for red skin apple and the genetic basis of skin color differentiation is very limited and still largely unknown. RESULTS: Here, we reported a bud sport mutant of Fuji apple with red skin color and enhanced anthocyanins accumulation. Quantitative SWATH-MS (sequential window acquisition of all theoretical spectra-mass spectrometry) proteomics investigations revealed proteome changes in the apple red skin bud mutation and a total of 451 differentially expressed proteins were identified in apple skin. The mutant showed significantly increased expression levels of photosynthesis-related proteins, stress-related proteins as well as anthocyanins biosynthesis pathway. On the other hand, substantial downregulation of mitogen-activated protein kinase 4 (MAPK4) and mevalonate kinase (MVK) were detected, indicating a promising role for the red skin color development in the mutant. Furthermore, we also hypothesize that a post-transcriptional regulation of the skin color formation occurs in the mutant through the advanced SWATH-MS analysis. CONCLUSION: Our work provides important information on the application of proteomic methods for analysing proteomes changes in Fuji apple and highlights a clade of regulatory proteins potentially contributing for the molecular breeding of fruit skin color.


Assuntos
Antocianinas/metabolismo , Regulação da Expressão Gênica de Plantas , Malus/fisiologia , Proteínas de Plantas/metabolismo , Proteoma , Frutas/genética , Frutas/imunologia , Frutas/metabolismo , Frutas/fisiologia , Malus/genética , Espectrometria de Massas , Mutação , Fotossíntese , Pigmentação , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteômica
8.
J Exp Bot ; 70(5): 1597-1611, 2019 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-30690492

RESUMO

Moderate soil drying imposed at the post-anthesis stage significantly increases starch accumulation in inferior grains of rice, but how this process is regulated at the level of gene expression remains unclear. In this study, we applied moderate drying (MD) treatments to the soil at the post-anthesis stage and followed the dynamics of the conversion process of soluble sugars to starch in inferior grains using RNA-seq analysis. An elevated level of ABA induced by MD was consistently associated with down-regulation of ABA8ox2, suggesting that lower expression of this gene may be responsible for the higher ABA content, potentially resulting in better filling in inferior grains. In addition, MD treatments up-regulated genes encoding five key enzymes involved sucrose-to-starch conversion and increased the activities of enzymes responsible for soluble-sugar reduction and starch accumulation in inferior grains. Differentially expressed transcription factors, including NAC, GATA, WRKY, and M-type MADS, were predicted to interact with other proteins in mediating filling of inferior grains as a response to MD. Transient expression analysis showed that NAC activated WAXY expression by binding to its promoter, indicating that NAC played a key role in starch synthesis of inferior grains under MD treatment. Our results provide new insights into the molecular mechanisms that regulate grain filling in inferior grains of rice under moderate soil drying.


Assuntos
Dessecação , Grão Comestível/crescimento & desenvolvimento , Oryza/fisiologia , Solo/química , Transcriptoma , Grão Comestível/genética
9.
J Exp Bot ; 70(3): 817-833, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30535157

RESUMO

Post-transcriptional mechanisms (PTMs), including alternative splicing (AS) and alternative translation initiation (ATI), may explain the diversity of proteins involved in plant development and stress responses. Transcriptional regulation is important during the hypoxic germination of rice seeds, but the potential roles of PTMs in this process have not been characterized. We used a combination of proteomics and RNA sequencing to discover how AS and ATI contribute to plant responses to hypoxia. In total, 10 253 intron-containing genes were identified. Of these, ~1741 differentially expressed AS (DAS) events from 811 genes were identified in hypoxia-treated seeds compared with controls. Over 95% of these were not present in the list of differentially expressed genes. In particular, regulatory pathways such as the spliceosome, ribosome, endoplasmic reticulum protein processing and export, proteasome, phagosome, oxidative phosphorylation, and mRNA surveillance showed substantial AS changes under hypoxia, suggesting that AS responses are largely independent of transcriptional regulation. Considerable AS changes were identified, including the preferential usage of some non-conventional splice sites and enrichment of splicing factors in the DAS data sets. Taken together, these results not only demonstrate that AS and ATI function during hypoxic germination but they have also allowed the identification of numerous novel proteins/peptides produced via ATI.


Assuntos
Processamento Alternativo , Germinação/genética , Oryza/crescimento & desenvolvimento , Biossíntese de Proteínas , Anaerobiose , Oryza/genética , Oxigênio/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/fisiologia
10.
Plant J ; 91(3): 518-533, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28407323

RESUMO

In eukaryotes, mechanisms such as alternative splicing (AS) and alternative translation initiation (ATI) contribute to organismal protein diversity. Specifically, splicing factors play crucial roles in responses to environment and development cues; however, the underlying mechanisms are not well investigated in plants. Here, we report the parallel employment of short-read RNA sequencing, single molecule long-read sequencing and proteomic identification to unravel AS isoforms and previously unannotated proteins in response to abscisic acid (ABA) treatment. Combining the data from the two sequencing methods, approximately 83.4% of intron-containing genes were alternatively spliced. Two AS types, which are referred to as alternative first exon (AFE) and alternative last exon (ALE), were more abundant than intron retention (IR); however, by contrast to AS events detected under normal conditions, differentially expressed AS isoforms were more likely to be translated. ABA extensively affects the AS pattern, indicated by the increasing number of non-conventional splicing sites. This work also identified thousands of unannotated peptides and proteins by ATI based on mass spectrometry and a virtual peptide library deduced from both strands of coding regions within the Arabidopsis genome. The results enhance our understanding of AS and alternative translation mechanisms under normal conditions, and in response to ABA treatment.


Assuntos
Ácido Abscísico/farmacologia , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Proteogenômica/métodos , Plântula/efeitos dos fármacos , Plântula/metabolismo , Processamento Alternativo/genética , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Éxons/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Genoma de Planta/efeitos dos fármacos , Genoma de Planta/genética , Íntrons/genética , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Plântula/genética
11.
Plant Cell Physiol ; 58(8): 1391-1404, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575477

RESUMO

Carbon reserves in rice straw (stem and sheath) before flowering contribute to a significant portion of grain filling. However, the molecular mechanism of carbon reserve remobilization from straw to grains remains unclear. In this study, super rice LYP9 and conventional rice 9311 showed different carbon reserve remobilization behaviors. The transcriptomic profiles of straws of LYP9 and 9311 were analyzed at three stages of grain filling. Among the differentially expressed genes (DGs), 5,733 genes were uniquely up- or down-regulated at 30 days after anthesis (DAA) between LYP9 and 9311 in comparison with 681 at 10 DAA and 495 at 20 DAA, suggesting that the gene expression profile of LYP9 was very different from that of 9311 at the late stage of grain filling. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and Gene Ontology (GO) classification of DGs both showed that the carbohydrate catabolic pathway, plant hormone signal transduction and photosynthesis pathway were enriched in DGs, suggesting their roles in carbon reserve remobilization, which explains to a certain extent the difference in non-structural carbohydrate content, photosynthesis and ABA content between the two cultivars during grain filling. Further comparative analysis and confirmation by quantitative real-time PCR and enzyme assays suggest that genes involved in trehalose synthesis (trehalose-phosphate phosphatase and trehalose 6-phosphate synthase/phosphatase), starch degradation (ß-amylase) and sucrose synthesis (sucrose-phosphate synthase and sucrose synthase) were important for carbon reserve remobilization, whereas ABA content was determined by the counteraction of NCED1 and ABA8ox1 genes. The higher expression level of all these genes and ABA content in 9311 resulted in better efficiency of carbon reserve remobilization in 9311 than in LYP9.


Assuntos
Regulação da Expressão Gênica de Plantas , Oryza/metabolismo , Caules de Planta/metabolismo , Sementes/crescimento & desenvolvimento , Ácido Abscísico/genética , Ácido Abscísico/metabolismo , Metabolismo dos Carboidratos/genética , Ontologia Genética , Oryza/genética , Oryza/crescimento & desenvolvimento , Caules de Planta/genética , Sementes/genética , Análise de Sequência de RNA , Amido/genética , Amido/metabolismo , Sacarose/metabolismo
12.
Nanotechnology ; 28(30): 305402, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28581437

RESUMO

Silver nanowires (AgNWs) and graphene are both promising candidates as a transparent conductive electrode (TCE) to replace expensive and fragile indium tin oxide (ITO) TCE. A synergistically optimized performance is expected when the advantages of AgNWs and graphene are combined. In this paper, the AgNW-graphene hybrid electrode is constructed by depositing a graphene layer on top of the network of AgNWs. Compared with the pristine AgNWs electrode, the AgNW-graphene TCE exhibits reduced sheet resistance, lower surface roughness, excellent long-term stability, and corrosion resistance in corrosive liquids. The graphene layer covering the AgNWs provides additional conduction pathways for electron transport and collection by the electrode. Benefiting from these advantages of the hybrid electrodes, we achieve a power conversion efficiency of 8.12% of inverted organic solar cells using PTB7:PC71BM as the active layer, which is compared to that of the solar cells based on standard ITO TCE but about 10% higher than that based on AgNWs TCE.

13.
Proc Natl Acad Sci U S A ; 110(4): 1548-53, 2013 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-23319631

RESUMO

Maintaining nitric oxide (NO) homeostasis is essential for normal plant physiological processes. However, very little is known about the mechanisms of NO modulation in plants. Here, we report a unique mechanism for the catabolism of NO based on the reaction with the plant hormone cytokinin. We screened for NO-insensitive mutants in Arabidopsis and isolated two allelic lines, cnu1-1 and 1-2 (continuous NO-unstressed 1), that were identified as the previously reported altered meristem program 1 (amp1) and as having elevated levels of cytokinins. A double mutant of cnu1-2 and nitric oxide overexpression 1 (nox1) reduced the severity of the phenotypes ascribed to excess NO levels as did treating the nox1 line with trans-zeatin, the predominant form of cytokinin in Arabidopsis. We further showed that peroxinitrite, an active NO derivative, can react with zeatin in vitro, which together with the results in vivo suggests that cytokinins suppress the action of NO most likely through direct interaction between them, leading to the reduction of endogenous NO levels. These results provide insights into NO signaling and regulation of its bioactivity in plants.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Citocininas/metabolismo , Óxido Nítrico/metabolismo , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Carboxipeptidases/genética , Carboxipeptidases/metabolismo , Citocininas/química , Citocininas/genética , Flores/crescimento & desenvolvimento , Flores/metabolismo , Genes de Plantas , Mutação , Doadores de Óxido Nítrico/farmacologia , Nitroprussiato/farmacologia , Ácido Peroxinitroso/metabolismo , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Zeatina/metabolismo , Zeatina/farmacologia
14.
Sci Adv ; 10(6): eadi9284, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38324683

RESUMO

Gasdermin D (GSDMD) serves as a vital mediator of inflammasome-driven pyroptosis. In our study, we have identified NU6300 as a specific GSDMD inhibitor that covalently interacts with cysteine-191 of GSDMD, effectively blocking its cleavage while not affecting earlier steps such as ASC oligomerization and caspase-1 processing in AIM2- and NLRC4-mediated inflammation. On the contrary, NU6300 robustly inhibits these earlier steps in NLRP3 inflammasome, confirming a unique feedback inhibition effect in the NLRP3-GSDMD pathway upon GSDMD targeting. Our study reveals a previously undefined mechanism of GSDMD inhibitors: NU6300 impairs the palmitoylation of both full-length and N-terminal GSDMD, impeding the membrane localization and oligomerization of N-terminal GSDMD. In vivo studies further demonstrate the efficacy of NU6300 in ameliorating dextran sodium sulfate-induced colitis and improving survival in lipopolysaccharide-induced sepsis. Overall, these findings highlight the potential of NU6300 as a promising lead compound for the treatment of inflammatory diseases.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Inflamassomos/metabolismo , Cisteína/metabolismo , Gasderminas , Lipoilação
15.
J Med Chem ; 67(9): 7516-7538, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38686671

RESUMO

The NLRP3 inflammasome has been recognized as a promising therapeutic target in drug discovery for inflammatory diseases. Our initial research identified a natural sesquiterpene isoalantolactone (IAL) as the active scaffold targeting NLRP3 inflammasome. To improve its activity and metabolic stability, a total of 64 IAL derivatives were designed and synthesized. Among them, compound 49 emerged as the optimal lead, displaying the most potent inhibitory efficacy on nigericin-induced IL-1ß release in THP-1 cells, with an IC50 value of 0.29 µM, approximately 27-fold more potent than that of IAL (IC50: 7.86 µM), and exhibiting higher metabolic stability. Importantly, 49 remarkably improved DSS-induced ulcerative colitis in vivo. Mechanistically, we demonstrated that 49 covalently bound to cysteine 279 in the NACHT domain of NLRP3, thereby inhibiting the assembly and activation of NLRP3 inflammasome. These results provided compelling evidence to further advance the development of more potent NLRP3 inhibitors based on this scaffold.


Assuntos
Desenho de Fármacos , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Sesquiterpenos , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Humanos , Inflamassomos/metabolismo , Inflamassomos/antagonistas & inibidores , Animais , Sesquiterpenos/farmacologia , Sesquiterpenos/síntese química , Sesquiterpenos/química , Camundongos , Relação Estrutura-Atividade , Interleucina-1beta/metabolismo , Células THP-1 , Colite Ulcerativa/tratamento farmacológico , Colite Ulcerativa/metabolismo , Camundongos Endogâmicos C57BL
16.
Eur J Med Chem ; 251: 115234, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36893624

RESUMO

P2X7R, which is a member of the purinergic P2 receptor family, is widely expressed in many immune cells, such as macrophages, lymphocytes, monocytes, and neutrophils. P2X7R is upregulated in response to proinflammatory stimulation, which is closely related to a variety of inflammatory diseases. The inhibition of P2X7 receptors has resulted in the elimination or reduction of symptoms in animal models of arthritis, depression, neuropathic pain, multiple sclerosis, and Alzheimer's disease. Therefore, the development of P2X7R antagonists is of great significance for the treatment of various inflammatory diseases. This review classifies the reported P2X7R antagonists according to their different cores, focuses on the structure-activity relationship (SAR) of the compounds, and analyzes some common substituents and strategies in the design of lead compounds, with the hope of providing valuable information for the development of new and efficient P2X7R antagonists.


Assuntos
Neuralgia , Animais , Relação Estrutura-Atividade , Macrófagos , Monócitos , Receptores Purinérgicos P2X7 , Antagonistas do Receptor Purinérgico P2X/farmacologia
17.
J Med Chem ; 66(21): 14447-14473, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37879043

RESUMO

NLRP3 inflammasome is a multiprotein complex involved in host immune response─which exerts various biological effects by mediating the maturation and secretion of IL-1ß and IL-18─and pyroptosis. However, its aberrant activation could cause amplification of inflammatory effects, thereby triggering a range of ailments, including Alzheimer's disease, Parkinson's disease, rheumatoid arthritis, gout, type 2 diabetes mellitus, and cancer. For the past few years, as an attractive anti-inflammatory target, NLRP3-targeting small-molecule inhibitors have been widely reported by both the academic and the industrial communities. In order to deeply understand the advancement of NLRP3 inflammasome inhibitors, we provide comprehensive insights and commentary on drugs currently under clinical investigation, as well as other NLRP3 inflammasome inhibitors from a chemical structure point of view, with an aim to provide new insights for the further development of clinical drugs for NLRP3 inflammasome-mediated diseases.


Assuntos
Artrite Reumatoide , Diabetes Mellitus Tipo 2 , Humanos , Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Interleucina-1beta , Piroptose
18.
J Med Chem ; 66(19): 13428-13451, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37756547

RESUMO

NLRP3 is an intracellular sensor protein that causes inflammasome formation and pyroptosis in response to a wide range of stimuli. Aberrant activation of NLRP3 inflammasome has been implicated in various chronic inflammatory diseases, making it a promising target for therapeutic intervention. In this work, a series of novel triazinone inhibitors of NLRP3 inflammasome were designed and synthesized. Compound L38 was identified for its excellent activity and acceptable metabolic stability among 41 compounds. Additionally, mechanism studies indicated that L38 inhibited NLRP3 inflammasome activation and pyroptosis by suppressing gasdermin D cleavage, ASC oligomerization, and NLRP3 inflammasome assembly while leaving mitochondrial ROS production, lysosome damage, and chloride/potassium efflux unaffected. Further investigation revealed that L38 could bind to the NACHT domain to exert inflammatory properties. Importantly, L38 exhibited positive therapeutic effects in DSS-induced ulcerative colitis mouse model. Taken together, this study presents a promising inhibitor of NLRP3 inflammasome deserving further investigation.


Assuntos
Colite Ulcerativa , Inflamassomos , Camundongos , Animais , Inflamassomos/metabolismo , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Camundongos Endogâmicos C57BL
19.
J Med Chem ; 66(16): 11365-11389, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37582195

RESUMO

Sepsis-associated acute kidney injury (AKI) is a serious clinical problem, without effective drugs. Abnormal activation of the purinergic P2X7 receptor (P2X7R) in septic kidneys makes its antagonist a promising therapeutic approach. Herein, a series of novel P2X7R antagonists were designed, synthesized, and structurally optimized. Based on in vitro potency in human/mouse P2X7R using HEK293 cells, hepatic microsomal stability, and pharmacokinetic and preliminary in vivo assessments, compound 14a was identified by respective human and mouse P2X7R IC50 values of 64.7 and 10.1 nM, together with favorable pharmacokinetic properties. Importantly, 14a dose-dependently alleviated kidney dysfunction and pathological injury in both lipopolysaccharide (LPS)- and cecal ligation/perforation (CLP)-induced septic AKI mice with a good safety profile. Mechanistically, 14a could suppress NLRP3 inflammasome activation to inhibit the expression of cleaved caspase-1, gasdermin D, IL-1ß, and IL-18 in the injured kidneys of septic mice. Collectively, these results highlighted that P2X7R antagonist 14a exerted a therapeutic potential against septic AKI.


Assuntos
Injúria Renal Aguda , Sepse , Animais , Humanos , Camundongos , Injúria Renal Aguda/tratamento farmacológico , Caspase 1/metabolismo , Células HEK293 , Inflamassomos/metabolismo , Rim/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Antagonistas do Receptor Purinérgico P2X/farmacologia , Antagonistas do Receptor Purinérgico P2X/uso terapêutico , Receptores Purinérgicos P2X7 , Sepse/tratamento farmacológico
20.
Phytomedicine ; 109: 154617, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36610140

RESUMO

BACKGROUND: Searching the targets of natural products is very important for drug discovery and elucidating the mechanism of drug action and disease. Honokiol (HK), as the major active component of Magnolia officinalis Rehder & E.H.Wilson, has been widely used in medicine and cosmetics. Among its bioactivities, its anti-inflammatory activity is particularly impressive. However, the target protein of HK in anti-inflammatory action and its regulatory mechanism are unclear. PURPOSE: Here, we identified the target protein and molecular mechanism of the anti- inflammatory action of HK. METHODS: First, an LPS-induced septic shock model and DSS-induced ulcerative colitis model were used to assess the anti-inflammatory efficacy of HK. Second, the drug affinity responsive target stability, proteomics analysis, thermal shift assays and cellular thermal shift assays were used to identify and validate the target of HK. Finally, western blot, ELISA, LDH immunofluorescence staining, shRNA and LC/MS for L-leucine analysis were performed to determine the mechanism of the anti-inflammatory action of HK. RESULTS: This study revealed that HK significantly alleviated LPS-induced septic shock and DSS-induced ulcerative colitis in vivo, suggesting that HK has significant anti-inflammatory activity. HK treatment dramatically reduced IL-1ß release and caspase-1 activation at different time points, showing that HK could inhibit both NLRP3 inflammasome priming and activation processes in cells. HK also suppressed adaptor apoptosis speck-like protein oligomerization. Mechanistically, SLC3A2 was identified as a direct target of HK in THP-1 cells. HK downregulated SLC3A2 expression by promoting its degradation via proteasome-mediated proteolysis. Further study demonstrated that HK triggered SLC3A2 to suppress NLRP3 inflammasome activation by significantly reducing the content of L-leucine transported into cells and lysosomes to block the mTORC1 pathway. CONCLUSIONS: Our work identified HK as a promising anti-inflammatory drug candidate through the SLC3A2/L-leucine/mTORC1/NLRP3 pathways.


Assuntos
Colite Ulcerativa , Choque Séptico , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Lipopolissacarídeos , Leucina , Anti-Inflamatórios/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA