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1.
Poult Sci ; 103(10): 104080, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-39106705

RESUMO

Aflatoxin B1 (AFB1) is a mycotoxin which is responsible for severe damage to the immune system of humans and livestock. Licochalcone A (Lico A), a polyphenol derived from turmeric, has attracted great attention due to its wonderful antioxidant properties. Ferroptosis, an iron-dependent cell death related to oxidative stress, which plays a crucial role in the resistance of phytochemical to immune-associated injury. Nevertheless, effects of Lico A on the bursa of broilers exposed to AFB1 remain unclear. In this work, broilers were fed diets supplemented with 2 mg/kg of AFB1 and 50 mg/kg of Lico A. Meanwhile, various concentrations of Lico A and AFB1 (15 µM) were used to stimulate macrophages. These results revealed that AFB1 resulted in more severe bursa atrophy and relative weight reduction; the expression of pro-ferroptosis protein ACSL4 and the content of malondialdehyde (MDA) were significantly elevated, while the expression of anti-ferroptosis proteins GPX4, xCT, FSP1 and the content of Glutathione (GSH) was obviously reduced. However, Lico A treatment effectively reversed these effects in the bursa of broilers. Meanwhile, in bursa and macrophages, Lico A mitigated the expression of AFB1-induced apoptosis-associated protein (Caspase-3, Bax, Bcl-2) as well as antioxidant protein (Nrf2, GCLM, HO-1). Importantly, ferroptosis was also observed in macrophages induced by AFB1. Lico A efficaciously alleviated AFB1-induced mitochondrial membrane potential decrease and reactive oxygen species (ROS) production in macrophages; in contrast, Lico A evidently inhibited AFB1-triggered ROS generation and cytotoxicity, which was disabled by the addition of Erastin. Moreover, Liproxstatin-1 significantly inhibited ROS generation induced by AFB1. In summary, the present study elucidates that the main mechanism by which Lico A attenuates AFB1-induced immunotoxicity is through the suppression of ferroptosis, apoptosis, mitochondrial damage and oxidative stress, which is promising for the improvement of immunotoxic effects of AFB1.

2.
Beilstein J Org Chem ; 20: 1476-1485, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38978744

RESUMO

Polyketides are a major class of natural products, including bioactive medicines such as erythromycin and rapamycin. They are often rich in stereocenters biosynthesized by the ketoreductase (KR) domain within the polyketide synthase (PKS) assembly line. Previous studies have identified conserved motifs in KR sequences that enable the bioinformatic prediction of product stereochemistry. However, the reliability and applicability of these prediction methods have not been thoroughly assessed. In this study, we conducted a comprehensive bioinformatic analysis of 1,762 KR sequences from cis-AT PKSs to reevaluate the residues involved in conferring stereoselectivity. Our findings indicate that the previously identified fingerprint motifs remain valid for KRs in ß-modules from actinobacteria, but their reliability diminishes for KRs from other module types or taxonomic origins. Additionally, we have identified several new motifs that exhibit a strong correlation with the stereochemical outcomes of KRs. These updated fingerprint motifs for stereochemical prediction not only enhance our understanding of the enzymatic mechanisms governing stereocontrol but also facilitate accurate stereochemical prediction and genome mining of polyketides derived from modular cis-AT PKSs.

3.
Front Plant Sci ; 15: 1413595, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974979

RESUMO

In response to the issue of harvesting machine failures affecting crop harvesting timing, this study develops an emergency scheduling model and proposes a hybrid optimization algorithm that combines a genetic algorithm and an ant colony algorithm. By enhancing the genetic algorithm's crossover and mutation methods and incorporating the ant colony algorithm, the proposed algorithm can prevent local optima, thus minimizing disruptions to the overall scheduling plan. Field data from Deyang, Sichuan Province, were utilized, and simulations on various harvesting machines experiencing random faults were conducted. Results indicated that the improved genetic algorithm reduced the optimal comprehensive scheduling cost during random fault occurrences by 47.49%, 19.60%, and 32.45% compared to the basic genetic algorithm and by 34.70%, 14.80%, and 24.40% compared to the ant colony algorithm. The improved algorithm showcases robust global optimization capabilities, high stability, and rapid convergence, offering effective emergency scheduling solutions in case of harvesting machine failures. Furthermore, a visual management system for agricultural machinery scheduling was developed to provide software support for optimizing agricultural machinery scheduling.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39054601

RESUMO

Low-cost sodium-ion batteries have demonstrated great prospects in energy storage, among which layered transition metal oxides hold great potential as a cathode material. However, the notorious phase transition in layered cathode materials has greatly hampered their cycle life due to large volume changes upon desodiation/sodiation. In this study, by adopting an O3-type NaNi1/3Fe1/3Mn1/3O2 (NFM) with controlled synthesis temperatures, we have revealed that the grain size is closely related to its phase transition behaviors. The layered material with a smaller grain size and more distorted lattice tends to experience a shorter plateau of the O3-P3-O3 phase transitions during the charge/discharge process. Despite having a lower nominal discharge capacity without the phase transition plateau, its cycling stability increases from 77.4% to 96.2% after 100 cycles with greatly reduced intragranular cracks. The smaller grain size and lattice distortion act as a barrier that prevents the smooth layer from gliding upon sodium intercalation and deintercalation. This study focuses on the influence of grain size on battery cycle stability and provides a basis for future analysis of the structural instability of layered materials.

5.
J Neuroinflammation ; 21(1): 186, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080649

RESUMO

Under subarachnoid hemorrhage (SAH) conditions, astrocytes undergo a marked intensification of glycolytic activity, resulting in the generation of substantial amounts of lactate to maintain the energy demand for neurons and other brain cells. Lactate has garnered increasing attention in recent years because of its emerging role in critical biological processes such as inflammation regulation and neuroprotection, particularly through its histone lactylation. Bromodomain-containing protein 4 (BRD4) plays a crucial role in maintaining neural development and promoting memory formation in the central nervous system. Nonetheless, the function and regulatory mechanism of BRD4 and histone lactylation in astrocytes following SAH remain elusive. Our findings indicate that BRD4, a crucial epigenetic regulator, plays a definitive role in histone lactylation. Both in vitro and in vivo, these results demonstrated that targeted silencing of BRD4 in astrocytes can significantly reduce H4K8la lactylation, thereby aggravating the A1 polarization of astrocytes and ultimately affecting the recovery of neural function and prognosis in mice after SAH. In summary, BRD4 plays a pivotal role in modulating astrocyte polarization following SAH via histone lactylation. Targeting this mechanism might offer an efficient therapeutic strategy for SAH.


Assuntos
Astrócitos , Proteínas que Contêm Bromodomínio , Histonas , Hemorragia Subaracnóidea , Fatores de Transcrição , Animais , Masculino , Camundongos , Astrócitos/metabolismo , Proteínas que Contêm Bromodomínio/metabolismo , Polaridade Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Histonas/metabolismo , Camundongos Endogâmicos C57BL , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Hemorragia Subaracnóidea/metabolismo , Hemorragia Subaracnóidea/patologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
6.
Fitoterapia ; 177: 106142, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39067487

RESUMO

The investigation of the leaves of Pittosporum elevaticostatum Chang et Yan led to the isolation of fifteen pentacyclic triterpenoids (1-15), including five previously undescribed ones (1-5), and nine others (16-24). The structures of compounds 1-5 were elucidated based on comprehensive spectroscopic techniques, including one dimension (1D) and 2D nuclear magnetic resonance (NMR), high resolution electrospray ionization mass spectroscopy (HR-ESI-MS), and other methods. Compounds 2 and 13 demonstrated significant inhibitory activity against Listeria monocytogenes (L. monocytogenes) with minimum inhibitory concentration (MIC) values of 32 µM. Scanning electron microscopy (SEM) observations revealed insights into the antibacterial mechanism, indicating that compounds 2 and 13 either prevent biofilm formation of dispersed the preformed cell membranes. Additionally, compounds 1, 5, 7, and 12 exhibited anti-inflammatory activity on lipopolysaccharide (LPS)-stimulated BV-2 microglial cells with IC50 values ranging from 11.27 to 17.80 µM.

7.
Phytomedicine ; 130: 155756, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38833791

RESUMO

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is a persistent liver condition that affects both human health and animal productive efficiency on a global scale. A number of naturally occurring compounds activate nuclear factor erythroid 2-related factor 2 (Nrf2) as a transcription factor with important protective effects against many liver diseases, including NAFLD. Raffinose (Ra), an oligosaccharide extracted from several plants, exhibits diverse biological functions. However, the uncertainty lies in determining whether the activation of Nrf2 by Ra can provide a preventive effect on liver lipotoxicity. PURPOSE: The aim of this study was to shed light on the molecular pathways by which Ra possesses its protective benefits against NAFLD. METHODS: Experimental protocols were established using WT and Nrf2-null (Nrf2-/-) mice. Liver samples from each group were collected for Western blot, RT-qPCR, H & E, Sirius red and Oil red O staining. Additionally, serums were processed for ELISA. ALM12 cells were gathered for Western blot and immunofluorescence. Moreover, to elucidate the molecular mechanism of Ra, molecular docking was performed. RESULTS: Our results indicated that Ra remarkably alleviated liver lipotoxic in vivo and in vitro. Ra treatment effectively corrected hepatic steatosis, the release of AST, ALT, TG, and TC, as well as the depletion of HDL and LDL. Meanwhile, Ra efficiently prevented inflammation by inhibiting the TLR4-MyD88-NF-κB pathway and pyroptosis. Additionally, these findings implied that Ra reduced the production of fibrosis-related proteins, which enhanced collagen deposition. Molecular docking revealed that Ra possessed the ability to bind specific regions of Nrf2, resulting in the enhancement of Nrf2 activation and nuclear translocation. Ra treatment restored serum redox factors and antioxidant enzymes to normal levels; however, these alterations were clearly reversed in Nrf2-/- mice. CONCLUSION: This study reveals novel information on Ra's protective benefits against liver injury caused by abnormal lipid metabolism; these effects are mostly mediated by Nrf2 activation, suggesting a potential new medicine or treatment strategy for NAFLD.


Assuntos
Fator 2 Relacionado a NF-E2 , Hepatopatia Gordurosa não Alcoólica , Piroptose , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Fator 2 Relacionado a NF-E2/metabolismo , Piroptose/efeitos dos fármacos , Camundongos , Receptor 4 Toll-Like/metabolismo , Masculino , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Inflamação/tratamento farmacológico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Simulação de Acoplamento Molecular , Antioxidantes/farmacologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Camundongos Knockout , Transdução de Sinais/efeitos dos fármacos , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo
8.
Adv Mater ; : e2406175, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38880979

RESUMO

Microstructural engineering on nickel-rich layered oxide (NRLO) cathode materials is considered a promising approach to increase both the capacity and lifespan of lithium-ion batteries by introducing high valence-state elements. However, rational regulation on NRLO microstructures based on a deep understanding of its capacity enhancement mechanism remains challenging. Herein for the first time, it is demonstrated that an increase of 14 mAh g-1 in reversible capacity at the first cycle can be achieved via tailoring the micro and nano structure of NRLO through introducing tungsten. Aberration-corrected scanning transmission electron microscopy (STEM) characterization reveals that the formation of a modified microstructure featured as coherent spinel twin boundaries. Theoretical modeling and electrochemical investigations further demonstrate that the capacity increase mechanism is related to such coherent spinel twin boundaries, which can lower the Li+ diffusion barrier and thus allow more Li+ to participate in deeper phase transitions. Meanwhile, the surface and grain boundaries of NRLOs are found to be modified by generating a dense and uniform LiWxOy phase, which further extends its cycle life by reducing side reactions with electrolytes. This work enables a comprehensive understanding of the capacity-increased mechanism and endows the remarkable potential of microstructural engineering for capacity- and lifespan-increased NRLOs.

9.
Future Oncol ; 20(18): 1267-1274, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38639577

RESUMO

Objective: Observational studies showed that Type 2 diabetes increased the risk of breast cancer, and vice versa. However, it is uncertain whether the link is causal or just due to confounding factors. Using bidirectional Mendelian randomization analysis, we assessed the bidirectional causal relationship from a genetic level. Methods: Large genome-wide association studies yielded summary-level data for Type 2 diabetes and breast cancer. Results: Genetically predicted Type 2 diabetes presented no statistically significant association with overall breast cancer or its subtypes. Similarly, genetically predicted overall breast cancer or its subtypes had no causal effect on Type 2 diabetes. Sensitivity analyses yielded similar results. Conclusion: Our bidirectional Mendelian randomization studies revealed no causal links between Type 2 diabetes and breast cancer.


[Box: see text].


Assuntos
Neoplasias da Mama , Diabetes Mellitus Tipo 2 , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/epidemiologia , Neoplasias da Mama/genética , Neoplasias da Mama/etiologia , Neoplasias da Mama/epidemiologia , Feminino , Fatores de Risco , Causalidade
10.
mSystems ; 9(4): e0126323, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38470142

RESUMO

Bacterial secondary metabolites serve as an important source of molecules for drug discovery. They also play an important function in mediating the interactions of microbial producers with their living environment and surrounding organisms. However, little is known about the genetic novelty, distribution, and community-level impacts of soil bacterial biosynthetic potential on a large geographic scale. Here, we constructed the first catalog of 11,149 biosynthetic gene clusters (BGCs) from agricultural soils across China and unearthed hidden biosynthetic potential for new natural product discovery from the not-yet-cultivated soil bacteria. Notably, we revealed soil pH as the strongest environmental driver of BGC biogeography and predicted that soil acidification and global climate change could damage the biosynthetic potential of the soil microbiome. The co-occurrence network of bacterial genomes revealed two BGC-rich species, i.e., Nocardia niigatensis from Actinobacteriota and PSRF01 from Acidobacteriota, as the module hub and connector, respectively, indicating their keystone positions in the soil microbial communities. We also uncovered a dominant role of BGC-inferred biotic interactions over environmental drivers in structuring the soil microbiome. Overall, this study achieved novel insights into the BGC landscape in agricultural soils of China, substantially expanding our understanding of the diversity and novelty of bacterial secondary metabolism and the potential role of secondary metabolites in microbiota assembly.IMPORTANCEBacterial secondary metabolites not only serve as the foundation for numerous therapeutics (e.g., antibiotics and anticancer drugs), but they also play critical ecological roles in mediating microbial interactions (e.g., competition and communication). However, our knowledge of bacterial secondary metabolism is limited to only a small fraction of cultured strains, thus restricting our comprehensive understanding of their diversity, novelty, and potential ecological roles in soil ecosystems. Here, we used culture-independent metagenomics to explore biosynthetic potentials in agricultural soils of China. Our analyses revealed a high degree of genetic diversity and novelty within biosynthetic gene clusters in agricultural soil environments, offering valuable insights for biochemists seeking to synthesize novel bioactive products. Furthermore, we uncovered the pivotal role of BGC-rich species in microbial communities and the significant relationship between BGC richness and microbial phylogenetic turnover. This information emphasizes the importance of biosynthetic potential in the assembly of microbial communities.


Assuntos
Microbiota , Solo , Solo/química , Filogenia , Microbiologia do Solo , Microbiota/genética , Bactérias/genética , Família Multigênica/genética
11.
Nat Commun ; 15(1): 1503, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374176

RESUMO

Nickel-rich layered oxide cathodes promise ultrahigh energy density but is plagued by the mechanical failure of the secondary particle upon (de)lithiation. Existing approaches for alleviating the structural degradation could retard pulverization, yet fail to tune the stress distribution and root out the formation of cracks. Herein, we report a unique strategy to uniformize the stress distribution in secondary particle via Kirkendall effect to stabilize the core region during electrochemical cycling. Exotic metal/metalloid oxides (such as Al2O3 or SiO2) is introduced as the heterogeneous nucleation seeds for the preferential growth of the precursor. The calcination treatment afterwards generates a dopant-rich interior structure with central Kirkendall void, due to the different diffusivity between the exotic element and nickel atom. The resulting cathode material exhibits superior structural and electrochemical reversibility, thus contributing to a high specific energy density (based on cathode) of 660 Wh kg-1 after 500 cycles with a retention rate of 86%. This study suggests that uniformizing stress distribution represents a promising pathway to tackle the structural instability facing nickel-rich layered oxide cathodes.

12.
Aging Dis ; 15(1): 390-407, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37307837

RESUMO

Neuroinflammation plays a crucial role in the pathogenesis and progression of Alzheimer's disease (AD). The Sterile Alpha and Toll Interleukin Receptor Motif-containing protein 1 (SARM1) has been shown to promote axonal degeneration and is involved in neuroinflammation. However, the role of SARM1 in AD remains unclear. In this study, we found that SARM1 was reduced in hippocampal neurons of AD model mice. Interestingly, conditional knockout (CKO) of SARM1 in the central nervous system (CNS, SARM1Nestin-CKO mice) delayed the cognitive decline in APP/PS1 AD model mice. Furthermore, SARM1 deletion reduced the Aß deposition and inflammatory infiltration in the hippocampus and inhibited neurodegeneration in APP/PS1 AD model mice. Further investigation into the underlying mechanisms revealed that the signaling of tumor necrosis factor-α (TNF-α) was downregulated in the hippocampus tissues of APP/PS1;SARM1Nestin-CKO mice, thereby alleviating the cognitive decline, Aß deposition and inflammatory infiltration. These findings identify unrecognized functions of SARM1 in promoting AD and reveal the SARM1-TNF-α pathway in AD model mice.


Assuntos
Doença de Alzheimer , Camundongos , Animais , Doença de Alzheimer/genética , Nestina , Camundongos Transgênicos , Fator de Necrose Tumoral alfa , Doenças Neuroinflamatórias , Transtornos da Memória/genética , Proteínas do Citoesqueleto/genética , Proteínas do Domínio Armadillo/genética
13.
Front Bioeng Biotechnol ; 11: 1233476, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37520291

RESUMO

With the increasing incidence of esophageal cancer, its diagnosis and treatment have become one of the key issues in medical research today. However, the current diagnostic and treatment methods face many unresolved issues, such as low accuracy of early diagnosis, painful treatment process for patients, and high recurrence rate after recovery. Therefore, new methods for the diagnosis and treatment of esophageal cancer need to be further explored, and the rapid development of nanomaterials has brought new ideas for solving this problem. Nanomaterials used as drugs or drug delivery systems possess several advantages, such as high drug capacity, adjustably specific targeting capability, and stable structure, which endow nanomaterials great application potential in cancer therapy. However, even though the nanomaterials have been widely used in cancer therapy, there are still few reviews on their application in esophageal cancer, and systematical overview and analysis are deficient. Herein, we overviewed the application of nanodrug systems in therapy and diagnosis of esophageal cancer and summarized some representative case of their application in diagnosis, chemotherapy, targeted drug, radiotherapy, immunity, surgery and new therapeutic method of esophageal cancer. In addition, the nanomaterials used for therapy of esophageal cancer complications, esophageal stenosis or obstruction and oesophagitis, are also listed here. Finally, the challenge and the future of nanomaterials used in cancer therapy were discussed.

14.
Neuroscience ; 524: 220-232, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37290684

RESUMO

Apolipoprotein E (apoE, protein; APOE, gene), divided into three alleles of E2, E3 and E4 in humans, is associated with the progression of white matter lesion load. However, mechanism evidence has not been reported regarding the APOE genotype in early white matter injury (WMI) under subarachnoid hemorrhage (SAH) conditions. In the present study, we investigated the effects of APOE gene polymorphisms, by constructing microglial APOE3 and APOE4-specific overexpression, on WMI and underlying mechanisms of microglia phagocytosis in a mice model of SAH. A total of 167 male C57BL/6J mice (weight 22-26 g) were used. SAH and bleeding environment were induced by endovascular perforation in vivo and oxyHb in vitro, respectively. Multi-technology approaches, including immunohistochemistry, high throughput sequencing, gene editing for adeno-associated viruses, and several molecular biotechnologies were used to validate the effects of APOE polymorphisms on microglial phagocytosis and WMI after SAH. Our results revealed that APOE4 significantly aggravated the WMI and decreased neurobehavioral function by impairing microglial phagocytosis after SAH. Indicators negatively associated with microglial phagocytosis increased like CD16, CD86 and the ratio of CD16/CD206, while the indicators positively associated with microglial phagocytosis decreased like Arg-1 and CD206. The increased ROS and aggravating mitochondrial damage demonstrated that the damaging effects of APOE4 in SAH may be associated with microglial oxidative stress-dependent mitochondrial damage. Inhibiting mitochondrial oxidative stress by Mitoquinone (mitoQ) can enhance the phagocytic function of microglia. In conclusion, anti-oxidative stress and phagocytosis protection may serve as promising treatments in the management of SAH.


Assuntos
Lesões Encefálicas , Hemorragia Subaracnóidea , Substância Branca , Camundongos , Humanos , Animais , Masculino , Apolipoproteína E4/genética , Apolipoproteína E4/metabolismo , Microglia/metabolismo , Hemorragia Subaracnóidea/genética , Hemorragia Subaracnóidea/metabolismo , Substância Branca/patologia , Camundongos Endogâmicos C57BL , Apolipoproteínas E/genética , Lesões Encefálicas/patologia , Apolipoproteína E3/metabolismo , Fagocitose/genética
15.
NPJ Biofilms Microbiomes ; 9(1): 30, 2023 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-37270554

RESUMO

The gut microbiota is now well known to affect the host's immune system. One way of bacterial communication with host cells is via the secretion of vesicles, small membrane structures containing various cargo. Research on vesicles secreted by Gram-positive gut bacteria, their mechanisms of interaction with the host and their immune-modulatory effects are still relatively scarce. Here we characterized the size, protein content, and immune-modulatory effects of extracellular vesicles (EVs) secreted by a newly sequenced Gram-positive human gut symbiont strain - Bifidobacterium longum AO44. We found that B. longum EVs exert anti-inflammatory effects, inducing IL-10 secretion from both splenocytes and dendritic cells (DC)-CD4+ T cells co-cultures. Furthermore, the EVs protein content showed enrichment in ABC transporters, quorum sensing proteins, and extracellular solute-binding proteins, which were previously shown to have a prominent function in the anti-inflammatory effect of other strains of B. longum. This study underlines the importance of bacterial vesicles in facilitating the gut bacterial immune-modulatory effects on the host and sheds light on bacterial vesicles as future therapeutics.


Assuntos
Bifidobacterium longum , Vesículas Extracelulares , Humanos , Fagocitose , Bactérias , Anti-Inflamatórios/farmacologia
16.
Biochem Pharmacol ; 212: 115583, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37148978

RESUMO

PD-1/PD-L1 blockade has achieved substantial clinical results in cancer treatment. However, the expression of other immune checkpoints leads to resistance and hinders the efficacy of PD-1/PD-L1 blockade. T cell immunoglobulin and mucin domain 3 (TIM-3), a non-redundant immune checkpoint, synergizes with PD-1 to mediate T cell dysfunction in tumor microenvironment. Development of small molecules targeting TIM-3 is a promising strategy for cancer immunotherapy. Here, to identify small molecule inhibitors targeting TIM-3, the docking pocket in TIM-3 was analyzed by Molecular Operating Environment (MOE) and the Chemdiv compound database was screened. The small molecule SMI402 could bind to TIM-3 with high affinity and prevent the ligation of PtdSer, HMGB1, and CEACAM1. SMI402 reinvigorated T cell function in vitro. In the MC38-bearing mouse model, SMI402 inhibited tumor growth by increasing CD8+ T and natural killing (NK) cells infiltration at the tumor site, as well as restoring the function of CD8+ T and NK cells. In conclusions, the small molecule SMI402 shows promise as a leading compound which targets TIM-3 for cancer immunotherapy.


Assuntos
Receptor Celular 2 do Vírus da Hepatite A , Neoplasias , Animais , Camundongos , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Receptor de Morte Celular Programada 1 , Antígeno B7-H1 , Neoplasias/tratamento farmacológico , Imunoterapia/métodos , Microambiente Tumoral
17.
J Neurotrauma ; 40(15-16): 1779-1795, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37078148

RESUMO

Traumatic brain injury (TBI) affects persons of all ages and is recognized as a major cause of death and disability worldwide; it also brings heavy life burden to patients and their families. The treatment of those with secondary injury after TBI is still scarce, however. Alternative splicing (AS) is a crucial post-transcriptional regulatory mechanism associated with various physiological processes, while the contribution of AS in treatment after TBI is poorly illuminated. In this study, we performed and analyzed the transcriptome and proteome datasets of brain tissue at multiple time points in a controlled cortical impact (CCI) mouse model. We found that AS, as an independent change against the transcriptional level, is a novel mechanism linked to cerebral edema after TBI. Bioinformatics analysis further indicated that the transformation of splicing isoforms after TBI was related to cerebral edema. Accordingly, we found that the fourth exon of transient receptor potential channel melastatin 4 (Trpm4) abrogated skipping at 72 h after TBI, resulting in a frameshift of the encoded amino acid and an increase in the proportion of spliced isoforms. Using magnetic resonance imaging (MRI), we have shown the numbers of 3nEx isoforms of Trpm4 may be positively correlated with volume of cerebral edema. Thus alternative splicing of Trpm4 becomes a noteworthy mechanism of potential influence on edema. In summary, alternative splicing of Trpm4 may drive cerebral edema after TBI. Trpm4 is a potential therapeutic targeting cerebral edema in patients with TBI.


Assuntos
Edema Encefálico , Lesões Encefálicas Traumáticas , Canais de Cátion TRPM , Camundongos , Animais , Edema Encefálico/genética , Edema Encefálico/tratamento farmacológico , Processamento Alternativo/genética , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/genética , Lesões Encefálicas Traumáticas/metabolismo , Encéfalo/patologia , Isoformas de Proteínas/genética , Canais de Cátion TRPM/genética , Canais de Cátion TRPM/metabolismo
18.
Plant Cell ; 35(8): 3053-3072, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37100425

RESUMO

The ketocarotenoid fucoxanthin and its derivatives can absorb blue-green light enriched in marine environments. Fucoxanthin is widely adopted by phytoplankton species as a main light-harvesting pigment, in contrast to land plants that primarily employ chlorophylls. Despite its supreme abundance in the oceans, the last steps of fucoxanthin biosynthesis have remained elusive. Here, we identified the carotenoid isomerase-like protein CRTISO5 as the diatom fucoxanthin synthase that is related to the carotenoid cis-trans isomerase CRTISO from land plants but harbors unexpected enzymatic activity. A crtiso5 knockout mutant in the model diatom Phaeodactylum tricornutum completely lacked fucoxanthin and accumulated the acetylenic carotenoid phaneroxanthin. Recombinant CRTISO5 converted phaneroxanthin into fucoxanthin in vitro by hydrating its carbon-carbon triple bond, instead of functioning as an isomerase. Molecular docking and mutational analyses revealed residues essential for this activity. Furthermore, a photophysiological characterization of the crtiso5 mutant revealed a major structural and functional role of fucoxanthin in photosynthetic pigment-protein complexes of diatoms. As CRTISO5 hydrates an internal alkyne physiologically, the enzyme has unique potential for biocatalytic applications. The discovery of CRTISO5 illustrates how neofunctionalization leads to major diversification events in evolution of photosynthetic mechanisms and the prominent brown coloration of most marine photosynthetic eukaryotes.


Assuntos
Diatomáceas , Xantofilas , Simulação de Acoplamento Molecular , Xantofilas/metabolismo , Carotenoides/metabolismo , Clorofila/metabolismo , Diatomáceas/genética , Diatomáceas/metabolismo
19.
Nat Nanotechnol ; 18(6): 602-610, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36894781

RESUMO

The ionic conductivity of composite solid-state electrolytes does not meet the application requirements of solid-state lithium (Li) metal batteries owing to the harsh space charge layer of different phases and low concentration of movable Li+. Herein, we propose a robust strategy for creating high-throughput Li+ transport pathways by coupling the ceramic dielectric and electrolyte to overcome the low ionic conductivity challenge of composite solid-state electrolytes. A highly conductive and dielectric composite solid-state electrolyte is constructed by compositing the poly(vinylidene difluoride) matrix and the BaTiO3-Li0.33La0.56TiO3-x nanowires with a side-by-side heterojunction structure (PVBL). The polarized dielectric BaTiO3 greatly promotes the dissociation of Li salt to produce more movable Li+, which locally and spontaneously transfers across the interface to coupled Li0.33La0.56TiO3-x for highly efficient transport. The BaTiO3-Li0.33La0.56TiO3-x effectively restrains the formation of the space charge layer with poly(vinylidene difluoride). These coupling effects contribute to a quite high ionic conductivity (8.2 × 10-4 S cm-1) and lithium transference number (0.57) of the PVBL at 25 °C. The PVBL also homogenizes the interfacial electric field with electrodes. The LiNi0.8Co0.1Mn0.1O2/PVBL/Li solid-state batteries stably cycle 1,500 times at a current density of 180 mA g-1, and pouch batteries also exhibit an excellent electrochemical and safety performance.


Assuntos
Eletrólitos , Lítio , Íons , Metais
20.
Chembiochem ; 24(9): e202200775, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36856079

RESUMO

Bioinformatics has become an indispensable tool for natural products research in the genomic era. One of the key challenges is to accurately convert sequence data of a biosynthetic gene cluster into chemical information such as the enzymatic function or the biosynthetic product structure. Type II polyketide synthase is the most bioinformatically well-studied class of non-modular biosynthetic machinery and represents a model system to showcase bioinformatic applications in natural products research. This review takes a bioinformatics-centered perspective and summarizes the past advances and future opportunities of bioinformatics-guided research on type II polyketide synthases. How bioinformatics has contributed to deepen the chemical understanding of type II PKSs will be discussed with the focus on enzymology, evolution, structural prediction of the biosynthetic products, genome mining, and the global analyses of their polyketide products.


Assuntos
Produtos Biológicos , Policetídeo Sintases , Policetídeo Sintases/genética , Policetídeo Sintases/química , Modelos Biológicos , Produtos Biológicos/química , Biologia Computacional
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