Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 253
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Mol Cell ; 82(7): 1278-1287.e5, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35271814

RESUMO

Cholesterol molecules specifically bind to the resting αßTCR to inhibit cytoplasmic CD3ζ ITAM phosphorylation through sequestering the TCR-CD3 complex in an inactive conformation. The mechanisms of cholesterol-mediated inhibition of TCR-CD3 and its activation remain unclear. Here, we present cryoelectron microscopy structures of cholesterol- and cholesterol sulfate (CS)-inhibited TCR-CD3 complexes and an auto-active TCR-CD3 variant. The structures reveal that cholesterol molecules act like a latch to lock CD3ζ into an inactive conformation in the membrane. Mutations impairing binding of cholesterol molecules to the tunnel result in the movement of the proximal C terminus of the CD3ζ transmembrane helix, thereby activating the TCR-CD3 complex in human cells. Together, our data reveal the structural basis of TCR inhibition by cholesterol, illustrate how the cholesterol-binding tunnel is allosterically coupled to TCR triggering, and lay a foundation for the development of immunotherapies through directly targeting the TCR-CD3 complex.


Assuntos
Complexo Receptor-CD3 de Antígeno de Linfócitos T , Linfócitos T , Complexo CD3/genética , Complexo CD3/metabolismo , Colesterol/metabolismo , Microscopia Crioeletrônica , Humanos , Complexo Receptor-CD3 de Antígeno de Linfócitos T/genética , Complexo Receptor-CD3 de Antígeno de Linfócitos T/metabolismo , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo
2.
Mol Cell ; 82(22): 4340-4352.e6, 2022 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-36309016

RESUMO

Adhesion G-protein-coupled receptors (aGPCRs) play key roles in a diversity of physiologies. A hallmark of aGPCR activation is the removal of the inhibitory GAIN domain and the dipping of the cleaved stalk peptide into the ligand-binding pocket of receptors; however, the detailed mechanism remains obscure. Here, we present cryoelectron microscopy (cryo-EM) structures of ADGRL3 in complex with Gq, Gs, Gi, and G12. The structures reveal unique ligand-engaging mode, distinctive activation conformation, and key mechanisms of aGPCR activation. The structures also reveal the uncharted structural information of GPCR/G12 coupling. A comparison of Gq, Gs, Gi, and G12 engagements with ADGRL3 reveals the key determinant of G-protein coupling on the far end of αH5 of Gα. A detailed analysis of the engagements allows us to design mutations that specifically enhance one pathway over others. Taken together, our study lays the groundwork for understanding aGPCR activation and G-protein-coupling selectivity.


Assuntos
Proteínas de Ligação ao GTP , Receptores Acoplados a Proteínas G , Ligantes , Microscopia Crioeletrônica , Receptores Acoplados a Proteínas G/metabolismo , Proteínas de Ligação ao GTP/metabolismo
3.
PLoS Biol ; 21(12): e3002384, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38048367

RESUMO

Neurons in primary visual cortex (area V1) are strongly driven by both sensory stimuli and non-sensory events. However, although the representation of sensory stimuli has been well characterized, much less is known about the representation of non-sensory events. Here, we characterize the specificity and organization of non-sensory representations in rat V1 during a freely moving visual decision task. We find that single neurons encode diverse combinations of task features simultaneously and across task epochs. Despite heterogeneity at the level of single neuron response patterns, both visual and nonvisual task variables could be reliably decoded from small neural populations (5 to 40 units) throughout a trial. Interestingly, in animals trained to make an auditory decision following passive observation of a visual stimulus, some but not all task features could also be decoded from V1 activity. Our results support the view that even in V1-the earliest stage of the cortical hierarchy-bottom-up sensory information may be combined with top-down non-sensory information in a task-dependent manner.


Assuntos
Córtex Visual , Percepção Visual , Animais , Ratos , Neurônios/fisiologia , Estimulação Luminosa/métodos , Córtex Visual Primário , Córtex Visual/fisiologia , Percepção Visual/fisiologia
4.
Proc Natl Acad Sci U S A ; 120(32): e2219905120, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37527341

RESUMO

Plasmodium falciparum multidrug resistance protein 1 (PfMDR1), an adenosine triphosphate (ATP)-binding cassette (ABC) transporter on the digestive vacuole (DV) membrane of the parasite, is associated with the resistance to antimalarial drugs. To understand the mechanisms of PfMDR1, we determined the cryo-electron microscopy structures of this transporter in different states. The transporter in the apo state shows an inward-facing conformation with a large cavity opening to the cytoplasm. Upon ATP binding and dimerization of the nucleotide-binding domains (NBDs), PfMDR1 displays an outward-facing conformation with a cavity toward the DV lumen. Drug resistance-associated mutations were investigated in both structures for their effects, and Y184F was identified as an allosteric activity-enhancing mutation. The amphiphilic substrate-binding site of PfMDR1 was revealed by the complex structure with the antimalarial drug mefloquine and confirmed by mutagenesis studies. Remarkably, a helical structure was found to hinder NBD dimerization and inhibit PfMDR1 activity. The location of this regulatory domain in the N terminus is different from the well-studied R domain in the internal linker region of other ABC transporter family members. The lack of the phosphorylation site of this domain also suggests a different regulation mechanism.


Assuntos
Antimaláricos , Malária Falciparum , Humanos , Plasmodium falciparum , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Microscopia Crioeletrônica , Antimaláricos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Resistência a Medicamentos/genética , Malária Falciparum/parasitologia
5.
Nano Lett ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940365

RESUMO

Cell migration requires the interplay among diverse migration patterns. The molecular basis of distinct migration programs is undoubtedly vital but not fully explored. Meanwhile, the lack of tools for investigating spontaneous migratory plasticity in a single living cell also adds to the hindrance. Here, we developed a micro/nanotechnology-enabled single-cell analytical platform to achieve coherent monitoring of spontaneous migratory pattern and signaling molecules. Via the platform, we unveiled a previously unappreciated STAT3 regionalization on the multifunctional regulations of migration. Specifically, nuclear STAT3 is associated with amoeboid migration, while cytoplasmic STAT3 promotes mesenchymal movement. Opposing effects of JAK2 multisite phosphorylation shape its response to STAT3 distribution in a dynamic and antagonistic manner, eventually triggering a reversible amoeboid-mesenchymal transition. Based on the above results, bioinformatics further revealed a possible downstream regulator of nucleocytoplasmic STAT3. Thus, our platform, as an exciting technological advance in single-cell migration research, can provide in-depth mechanism interpretations of tumor metastasis and progression.

6.
Small ; : e2403136, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770989

RESUMO

Hollandite-type manganese dioxide (α-MnO2) is recognized as a promising cathode material upon high-performance aqueous zinc-ion batteries (ZIBs) owing to the high theoretical capacities, high working potentials, unique Zn2+/H+ co-insertion chemistry, and environmental friendliness. However, its practical applications limited by Zn2+ accommodation, where the strong coulombic interaction and sluggish kinetics cause significant lattice deformation, fast capacity degradation, insufficient rate capability, and undesired interface degradation. It remains challenging to accurately modulate H+ intercalation while suppressing Zn2+ insertion for better lattice stability and electrochemical kinetics. Herein, proton Grotthuss transfer channels are first tunneled by shielding MnO2 with hydrophilic-zincophobic heterointerface, fulfilling the H+-dominating diffusion with the state-of-the-art ZIBs performance. Local atomic structure and theoretical simulation confirm that surface-engineered α-MnO2 affords to the synergy of Mn electron t2g-eg activation, oxygen vacancy enrichment, selective H+ Grotthuss transfer, and accelerated desolvation kinetics. Consequently, fortified α-MnO2 achieves prominent low current density cycle stability (≈100% capacity retention at 1 C after 400 cycles), remarkable long-lifespan cycling performance (98% capacity retention at 20 C after 12 000 cycles), and ultrafast rate performance (up to 30 C). The study exemplifies a new approach of heterointerface engineering for regulation of H+-dominating Grotthuss transfer and lattice stabilization in α-MnO2 toward reliable ZIBs.

7.
Cancer Cell Int ; 24(1): 32, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38229092

RESUMO

BACKGROUND: Bladder cancer is the second most common genitourinary malignancy worldwide. The death rate of bladder cancer has increased every year. However, the molecular mechanism of bladder cancer is not sufficiently studied. Deubiquitinating enzymes (DUBs) play an important role in carcinogenesis. Several studies have demonstrated that USP5 associated with malignancy and pathological progression in hepatocellular carcinoma, colorectal and non-small cell lung cancer. However, the role of USP5 in bladder cancer need to be explored. METHODS: The USP5 expression was analysed using the web server GEPIA. To explore USP5 function in bladder cancer, we constructed USP5-knockout cell lines in T24 cells. A FLAG-USP5 (WT USP5) plasmid and a plasmid FLAG-USP5 C335A (catalytic-inactive mutant) used to overexpress USP5 in EJ cells. CCK8, colony formation, transwell and scratch assays were used to assess cell viability, proliferation and migration. RNA sequencing (RNA-seq) and dual-luciferase reporter assays were performed to screen the pathway. Coimmunoprecipitation and immunofluorescence were used to explore the interaction between USP5 and c-Jun. Cycloheximide (CHX) chase assays were performed to establish the effect of USP5 on c-Jun stability. Xenograft mouse model was used to study the role of USP5 in bladder cancer. RESULTS: USP5 expression is increased in bladder cancer patients. Genetic ablation of USP5 markedly inhibited bladder cancer cell proliferation, viability, and migration both in vitro and in vivo. RNA-seq and luciferase pathway screening showed that USP5 activated JNK signalling, and we identified the interaction between USP5 and c-Jun. USP5 was found to activate c-Jun by inhibiting its ubiquitination. CONCLUSIONS: Our results show that high USP5 expression promotes bladder cancer progression by stabilizing c-Jun and that USP5 is a potential therapeutic target in bladder cancer.

8.
Nat Chem Biol ; 18(3): 281-288, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34937912

RESUMO

Sphingosine-1-phosphate receptor 1 (S1PR1) is a master regulator of lymphocyte egress from the lymph node and an established drug target for multiple sclerosis (MS). Mechanistically, therapeutic S1PR1 modulators activate the receptor yet induce sustained internalization through a potent association with ß-arrestin. However, a structural basis of biased agonism remains elusive. Here, we report the cryo-electron microscopy (cryo-EM) structures of Gi-bound S1PR1 in complex with S1P, fingolimod-phosphate (FTY720-P) and siponimod (BAF312). In combination with functional assays and molecular dynamics (MD) studies, we reveal that the ß-arrestin-biased ligands direct a distinct activation path in S1PR1 through the extensive interplay between the PIF and the NPxxY motifs. Specifically, the intermediate flipping of W2696.48 and the retained interaction between F2656.44 and N3077.49 are the key features of the ß-arrestin bias. We further identify ligand-receptor interactions accounting for the S1PR subtype specificity of BAF312. These structural insights provide a rational basis for designing novel signaling-biased S1PR modulators.


Assuntos
Cloridrato de Fingolimode , Esclerose Múltipla , Microscopia Crioeletrônica , Cloridrato de Fingolimode/farmacologia , Cloridrato de Fingolimode/uso terapêutico , Humanos , Esclerose Múltipla/tratamento farmacológico , Receptores de Esfingosina-1-Fosfato , beta-Arrestinas
9.
Cell Commun Signal ; 22(1): 340, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38907234

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC) is recognized as the most aggressive and immunologically infiltrated subtype of breast cancer. A high circulating neutrophil-to-lymphocyte ratio (NLR) is strongly linked to a poor prognosis among patients with breast cancer, emphasizing the critical role of neutrophils. Although the involvement of neutrophils in tumor metastasis is well documented, their interactions with primary tumors and tumor cells are not yet fully understood. METHODS: Clinical data were analyzed to investigate the role of neutrophils in breast cancer. In vivo mouse model and in vitro co-culture system were used for mechanism researches. Blocking experiments were further performed to identify therapeutic agents against TNBC. RESULTS: TNBC cells secreted GM-CSF to sustain the survival of mature neutrophils and upregulated CD11b expression. Through CD11b, neutrophils specifically binded to ICAM1 on TNBC cells, facilitating adhesion. Transcriptomic sequencing combined with human and murine functional experiments revealed that neutrophils, through direct CD11b-ICAM1 interactions, activated the MAPK signaling pathway in TNBC cells, thereby enhancing tumor cell invasion and migration. Atorvastatin effectively inhibited ICAM1 expression in tumor cells, and tumor cells with ICAM1 knockout or treated with atorvastatin were unresponsive to neutrophil activation. The MAPK pathway and MMP9 expression were significantly inhibited in the tumor tissues of TNBC patients treated with atorvastatin. CONCLUSIONS: Targeting CD11b-ICAM1 with atorvastatin represented a potential clinical approach to reduce the malignant characteristics of TNBC.


Assuntos
Antígeno CD11b , Adesão Celular , Molécula 1 de Adesão Intercelular , Neutrófilos , Neoplasias de Mama Triplo Negativas , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neutrófilos/metabolismo , Humanos , Animais , Antígeno CD11b/metabolismo , Antígeno CD11b/genética , Feminino , Molécula 1 de Adesão Intercelular/metabolismo , Molécula 1 de Adesão Intercelular/genética , Camundongos , Linhagem Celular Tumoral , Progressão da Doença , Movimento Celular
10.
Cancer Control ; 31: 10732748241255212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38769789

RESUMO

OBJECTIVE: A high number of Non-Small Cell Lung Cancer (NSCLC) patients with brain metastasis who have not had surgery often have a negative outlook. Radiotherapy remains a most common and effective method. Nomograms were developed to forecast the cancer-specific survival (CSS) and overall survival (OS) in NSCLC individuals with nonoperative brain metastases who underwent radiotherapy. METHODS: Information was gathered from the Surveillance, Epidemiology, and End Results (SEER) database about patients diagnosed with NSCLC who had brain metastases not suitable for surgery. Nomograms were created and tested using multivariate Cox regression models to forecast CSS and OS at intervals of 1, 2, and 3 years. RESULTS: The research involved 3413 individuals diagnosed with NSCLC brain metastases who had undergone radiotherapy but had not experienced surgery. These participants were randomly divided into two categories. The analysis revealed that gender, age, ethnicity, marital status, tumor location, tumor laterality, tumor grade, histology, T stage, N stage, chemotherapy, tumor size, lung metastasis, bone metastasis, and liver metastasis were significant independent predictors for OS and CSS. The C-index for the training set for predicting OS was .709 (95% CI, .697-.721), and for the validation set, it was .705 (95% CI, .686-.723), respectively. The C-index for predicting CSS was .710 (95% CI, .697-.722) in the training set and .703 (95% CI, .684-.722) in the validation set, respectively. The nomograms model, as suggested by the impressive C-index, exhibits outstanding differentiation ability. Moreover, the ROC and calibration curves reveal its commendable precision and distinguishing potential. CONCLUSIONS: For the first time, highly accurate and reliable nomograms were developed to predict OS and CSS in NSCLC patients with non-surgical brain metastases, who have undergone radiotherapy treatment. The nomograms may assist in tailoring counseling strategies and choosing the most effective treatment method.


Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nomogramas , Programa de SEER , Humanos , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Masculino , Feminino , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/mortalidade , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Pessoa de Meia-Idade , Idoso , Prognóstico , Adulto
11.
BMC Psychiatry ; 24(1): 146, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38383298

RESUMO

BACKGROUND: To investigate the incidence of depression in middle-aged and elderly patients with diabetes in China and the influencing factors to provide a theoretical basis to improve the mental health of middle-aged and elderly patients with diabetes and formulate prevention, control, and intervention strategies. METHODS: The sample of this study was obtained from the China Health and Aging Tracking Survey (CHARLS) 2018 survey data, and middle-aged and older patients with diabetes(responding "Yes" to the questionnaire: "Have you ever been told by a doctor that you have diabetes or elevated blood glucose [including abnormal glucose tolerance and elevated fasting glucose]?") aged ≥ 45 years were selected as study subjects (n = 2,613 ). Depressive symptoms of the study subjects were determined using the simplified version of the Depression Scale for Epidemiological Surveys scores(a score ≥ 10 was defined as depression), influence factors were analyzed using binary logistic regression, and proportion of depressive symptoms was standardized using the sex ratio of the seventh census. RESULTS: Among the 2,613 middle-aged and elderly patients with diabetes, 1782 (68.2%) had depressive symptoms and 831 (31.8%) had no depressive symptoms. There were 481 (27.0%) patients aged 45-59 years, 978 (54.9%) aged 60-74 years, and 323 (18.1%) aged ≥ 75 years. The depression rate among middle-aged and elderly Chinese patients with diabetes after standardization correction was 67.5%. Binary logistic regression results showed that age, education level, life satisfaction, marital satisfaction, self-rated health grade, somatic pain, visual impairment, physical disability, and the presence of comorbid chronic diseases were factors that influenced the onset of depression in middle-aged and elderly Chinese patients with diabetes (P < 0.05). CONCLUSION: According to a survey analysis of the CHARLS 2018 data, depression is influenced by a combination of factors among middle-aged and elderly patients with diabetes in China. Therefore, for this population, targeted prevention and control should be carried out for key populations, such as middle-aged and elderly people, poor physical health, and low life satisfaction and marital satisfaction, from various dimensions (e.g., demographic and sociological factors, physical health status, and life satisfaction and marital satisfaction).


Assuntos
Depressão , Diabetes Mellitus , Idoso , Pessoa de Meia-Idade , Humanos , Depressão/epidemiologia , Depressão/psicologia , Incidência , Diabetes Mellitus/epidemiologia , Envelhecimento , Glucose , China/epidemiologia , Estudos Longitudinais
12.
BMC Anesthesiol ; 24(1): 81, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413909

RESUMO

BACKGROUND: This study was identified the risk factors for and designed to investigate influence of postoperative moderate-to-severe pain of post anaesthesia care unit (PACU) in patients with malignancy. METHODS: A retrospective study was performed on 22,600 cancer patients with malignancy who underwent elective radical surgery in the new hospital of First Affiliated Hospital of Wenzhou Medical University, between January 2016 and June 2021. All patients were transferred to the PACU after tracheal extubation. Patients were divided into two groups according to a visual analogue scale (VAS) score of > 3: the no-moderate-severe-pain group and moderate-to-severe-pain group. Data pertaining to demographic, surgical, anaesthetic, and other factors were recorded. Lasso and logistic regression analysis was performed to explore the risk factors, then a nomogram was constructed to predict the moderate-severe-pain in the PACU. Validation was performed by using another 662 cancer patients in old hospital. The ROC curves and calibration curve were used to evaluate the accuracy and predictive ability of the nomogram. RESULTS: The incidence of postoperative moderate-to-severe pain of PACU in patients with malignancy was 1.42%. Gender, type of surgery, postoperative use of PCA, intraoperative adjuvant opioid agonists, NSAIDS, epidural analgesia, duration of anaesthesia, intraoperative massive haemorrhage, PACU vomiting were independent predictors for postoperative moderate-to-severe pain of PACU in the patients with malignancy. The area under the ROC curve of the predictive models in the primary and validation groups were 0.817 and 0.786, respectively. Moderate-to-severe pain in the PACU correlated with hypertension, hyperglycaemia, agitation, and hypoxemia (P < 0.05). CONCLUSIONS: The prediction model for postoperative moderate-to-severe pain of PACU in patients with malignancy has good predictive ability and high accuracy, which is helpful for PACU medical staff to identify and prevent postoperative moderate-to-severe pain in advance. TRIAL REGISTRATION: The study was approved by the Clinical Research Ethics Committee of the First Affiliated Hospital of Wenzhou Medical University (No.KY2021-097) and registered in the Chictr.org.cn registration system on 06/12/2021 (ChiCTR2100054013).


Assuntos
Analgesia Epidural , Anestesia , Neoplasias , Humanos , Estudos Retrospectivos , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/prevenção & controle , Neoplasias/complicações , Neoplasias/cirurgia
13.
Sensors (Basel) ; 24(11)2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38894081

RESUMO

Radio frequency interference (RFI) significantly hampers the target detection performance of frequency-modulated continuous-wave radar. To address the problem and maintain the target echo signal, this paper proposes a priori assumption on the interference component nature in the radar received signal, as well as a method for interference estimation and mitigation via time-frequency analysis. The solution employs Fourier synchrosqueezed transform to implement the radar's beat signal transformation from time domain to time-frequency domain, thus converting the interference mitigation to the task of time-frequency distribution image restoration. The solution proposes the use of image processing based on the dual-tree complex wavelet transform and combines it with the spatial domain-based approach, thereby establishing a dual-domain fusion interference filter for time-frequency distribution images. This paper also presents a convolutional neural network model of structurally improved UNet++, which serves as the interference estimator. The proposed solution demonstrated its capability against various forms of RFI through the simulation experiment and showed a superior interference mitigation performance over other CNN model-based approaches.

14.
Funct Integr Genomics ; 23(4): 345, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-37996761

RESUMO

Neuroinflammation and oxidative stress damage are involved in the pathogenesis of cerebral ischemia-reperfusion injury (CIRI). Ferroptosis emerged as a new player in the regulation of lipid peroxidation processes. This study aimed at exploring the potential involvement of ciprofol on ferroptosis-associated CIRI and subsequent neurological deficits in the mouse model of transient cerebral ischemia and reperfusion. Cerebral ischemia was built in male C57BL/6 J wild-type (WT) and Nrf2-knockout (Nrf2 KO) mice in the manner of middle cerebral artery occlusion (MCAO) followed by reperfusion. Ciprofol improved autonomic behavior, alleviated reactive oxygen species output and ferroptosis-induced neuronal death by nucleus transportation of NFE2 like BZIP transcription factor 2 (Nrf2) and the promotion of heme oxygenase 1 (Ho-1), solute carrier family 7 member 11 (SLC7A11/xCT), and glutathione peroxidase 4 (GPX4). Additionally, ciprofol improved neurological scores and reduced infarct volume, brain water content, and necrotic neurons. Cerebral blood flow in MCAO-treated mice was also improved. Furthermore, absence of Nrf2 abrogated the neuroprotective actions of ciprofol on antioxidant capacity and sensitized neurons to oxidative stress damage. In vitro, the primary-cultured cortical neurons from mice were pre-treated with oxygen-glucose deprivation/reperfusion (OGD/R), followed by ciprofol administration. Ciprofol effectively reversed OGD/R-induced ferroptosis and accelerated transcription of GPX4 and xCT. In conclusion, we investigated the ciprofol-induced inhibition effect of ferroptosis-sheltered neurons from lipid preoxidation in the pathogenesis of CIRI via Nrf2-xCT-GPX4 signaling pathway.


Assuntos
Anestésicos , Isquemia Encefálica , Fármacos Neuroprotetores , Estresse Oxidativo , Traumatismo por Reperfusão , Animais , Masculino , Camundongos , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/farmacologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Anestésicos/farmacologia
15.
Anal Chem ; 95(47): 17246-17255, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37963214

RESUMO

Biomacromolecules exist and function in a crowded and spatially confined intracellular milieu. Single-cell analysis has been an essential tool for deciphering the molecular mechanisms of cell biology and cellular heterogeneity. However, a sound understanding of in vivo environmental effects on single-cell quantification has not been well established. In this study, via cell mimicking with giant unilamellar vesicles and single-cell analysis by an approach called plasmonic immunosandwich assay (PISA) that we developed previously, we investigated the effects of two in vivo environmental factors, i.e., molecular crowding and spatial confinement, on quantitative biochemistry in the cytoplasm of single cells. We find that molecular crowding greatly affects the biomolecular interactions and immunorecognition-based detection while the effect of spatial confinement in cell-sized space is negligible. Without considering the effect of molecular crowding, the results by PISA were found to be apparently under-quantitated, being only 29.5-50.0% of those by the calibration curve considering the effect of molecular crowding. We further demonstrated that the use of a calibration curve established with standard solutions containing 20% (wt) polyethylene glycol 6000 can well offset the effect of intracellular crowding and thereby provide a simple but accurate calibration for the PISA measurement. Thus, this study not only sheds light on how intracellular environmental factors influence biomolecular interactions and immunorecognition-based single-cell quantification but also provides a simple but effective strategy to make the single-cell analysis more accurate.

16.
J Neuroinflammation ; 20(1): 284, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38037161

RESUMO

BACKGROUND: Neuroinflammation mediated by microglial pyroptosis is an important pathogenic mechanism of septic encephalopathy (SAE). It has been reported that TRIM45 is associated with tumours and inflammatory diseases. However, the role of TRIM45 in SAE and the relationship between TRIM45 and microglial pyroptosis are unknown. In this study, we found that TRIM45 played an important role in regulating microglial pyroptosis and the molecular mechanism. METHODS: SAE was induced by intraperitoneal injection of LPS in WT and AAV-shTRIM45 mice. BV2 cells were treated with LPS/ATP in vitro. Cognitive function was assessed by the Morris water maze. Nissl staining was used to evaluate histological and structural lesions. ELISA was used to dectect neuroinflammation. qPCR was used to detect the mRNA levels of inflammatory cytokines, NLRP3, and autophagy genes. Western blotting and immunofluorescence analysis were used to analyse the expression of the proteins. Changes in reactive oxygen species (ROS) in cells were observed by flow cytometry. Changes in mitochondrial membrane potential in BV2 cells were detected by JC-1 staining. Peripheral blood mononuclear cells were extracted from blood by density gradient centrifugation and then used for qPCR, western blotting and flow detection. To further explore the mechanism, we used the overexpression plasmids TRIM45 and Atg5 as well as siRNA-TRIM45 and siRNA-Atg5 to analyse the downstream pathway of NLRP3. The protein and mRNA levels of TRIM45 in peripheral blood mononuclear cells from sepsis patients were examined. RESULTS: Knocking down TRIM45 protected against neuronal damage and cognitive impairment in septic mice. TRIM45 knockdown inhibited microglial pyroptosis and the secretion of inflammatory cytokines in vivo and in vitro, which was mediated by NLRP3/Gsdmd-N activation. Overexpression of TRIM45 could activate NLRP3 and downstream proteins. Further examination showed that TRIM45 regulated the activation of NLRP3 by altering Atg5 and regulating autophagic flux. It was also found that overexpression and knockdown of TRIM45 affected the changes in ROS and mitochondrial membrane potential. Thus, knocking down TRIM45 could reduce microglial pyroptosis, the secretion of proinflammatory cytokines, and neuronal damage and improve cognitive function. In addition, the level of TRIM45 protein in septic patients was increased. There was a positive linear correlation between APACHE II score and TRIM45, between SOFA score and TRIM45. Compared to group GCS > 9, level of TRIM45 were increased in group GCS ≤ 8. CONCLUSION: TRIM45 plays a key role in neuroinflammation caused by LPS, and the mechanism may involve TRIM45-mediated exacerbation of microglial pyroptosis via the Atg5/NLRP3 axis.


Assuntos
Piroptose , Encefalopatia Associada a Sepse , Animais , Humanos , Camundongos , Citocinas/genética , Inflamassomos , Leucócitos Mononucleares , Lipopolissacarídeos , Microglia , Doenças Neuroinflamatórias , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Espécies Reativas de Oxigênio , Proteínas Repressoras , RNA Mensageiro , RNA Interferente Pequeno
17.
Opt Lett ; 48(19): 5049-5052, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37773382

RESUMO

In this work, we propose a compact effective surface plasmon polariton (CESPP) transmission line (TL) based on a structural dispersion-induced surface plasmon polaritons (SPPs) mode, which can enhance confinement while ensuring that the working bandwidth is not reduced. The dispersion relation of the CESPPs proposed in this article indicates that the shallower the groove, the stronger the confinement. Furthermore, the CESPPs may facilitate longitudinal miniaturization, since the configuration of the unit cell is simple. The coupling effect between two CESPP TLs has been well studied, revealing that excellent cross talk suppression can be achieved. The measurement results exhibit strong agreement with full-wave simulations, suggesting that the proposed CESPP TL holds significant potential for valuable applications in modern high-speed circuits.

18.
Neurochem Res ; 48(12): 3597-3609, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37561258

RESUMO

BACKGROUND AND PURPOSE: Morphine is amongst the most effective analgesics available for the management of severe pain. However, prolonged morphine treatment leads to analgesic tolerance which limits its clinical usage. Previous studies have demonstrated that melatonin ameliorates morphine tolerance by reducing neuroinflammation. However, little is known about the relationship between Toll like receptor 2 (TLR2) and neuroinflammation in morphine tolerance. The aim of this study was to explore the role of TLR2 in morphine tolerance and its connections with melatonin and Nod-like receptor protein 3 (NLRP3) inflammasome. METHODS: Sprague-Dawley rats were treated with morphine for 7 days and tail-flick latency test was performed to identify the induction of analgesic tolerance. The roles of TLR2 in microglia activation and morphine tolerance were assessed pharmacologically, and the possible interactions between melatonin, TLR2 and NLRP3 inflammasome were investigated. KEY RESULTS: Morphine tolerance was accompanied by increased TLR2 expression and NLRP3 inflammasome activation in spinal cord. whereas melatonin level was down-regulated. Chronic melatonin administration resulted in a reduced TLR2 expression and NLRP3 inflammasome activation. Moreover, the analgesic effect of morphine was partially restored. Inhibition of TLR2 suppressed the microglia and NLRP3 inflammasome activation, as well as restored the spinal melatonin level while attenuated the development of morphine tolerance. Furthermore, the inhibition of microglia activation ameliorated morphine tolerance via inhibiting TLR2-NLRP3 inflammasome signaling in spinal cord. CONCLUSION: In this study, we directly demonstrate a TLR2-melatonin negative feedback loop regulating microglia and NLRP3 inflammasome activation during the development of morphine tolerance.


Assuntos
Melatonina , Morfina , Ratos , Animais , Morfina/farmacologia , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Receptor 2 Toll-Like/metabolismo , Melatonina/farmacologia , Melatonina/uso terapêutico , Melatonina/metabolismo , Proteínas NLR/metabolismo , Doenças Neuroinflamatórias , Retroalimentação , Ratos Sprague-Dawley , Analgésicos/farmacologia , Microglia/metabolismo
19.
Immunol Invest ; 52(7): 925-939, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37732637

RESUMO

Acute lung injury (ALI) is a common lung disease with increasing morbidity and mortality rates due to the lack of specific drugs. Impaired alveolar fluid clearance (AFC) is a primary pathological feature of ALI. Epithelial sodium channel (ENaC) is a primary determinant in regulating the transport of Na+ and the clearance of alveolar edema fluid. Therefore, ENaC is an important target for the development of drugs for ALI therapy. However, the role of ENaC in the progression of ALI remains unclear. Inhibition of early growth response factor (EGR-1) expression has been reported to induce a protective effect on ALI; therefore, we evaluated whether EGR-1 participates in the progression of ALI by regulating ENaC-α in alveolar epithelium. We investigated the potential mechanism of EGR-1-mediated regulation of ENaC in ALI. We investigated whether EGR-1 aggravates the pulmonary edema response in ALI by regulating ENaC. ALI mouse models were established by intrabronchial injection of lipopolysaccharides (LPS). Lentiviruses with EGR-1 knockdown were transfected into LPS-stimulated A549 cells. We found that EGR-1 expression was upregulated in the lung tissues of ALI mice and in LPS-induced A549 cells, and was negatively correlated with ENaC-α expression. Knockdown of EGR-1 increased ENaC-α expression and relieved cellular edema in ALI. Moreover, EGR-1 regulated ENaC-α expression at the transcriptional level, and correspondingly promoted pulmonary edema and aggravated ALI symptoms. In conclusion, our study demonstrated that EGR-1 could promote pulmonary edema by downregulating ENaC-α at the transcriptional level in ALI. Our study provides a new potential therapeutic strategy for treatment of ALI.


EGR-1 expression was increased in LPS-induced ALI mice and associated with aggravated pulmonary edemaEGR-1 induced pulmonary edema relying on regulating the expression of ENaC-α at the transcriptional level by manipulating the promoter.


Assuntos
Lesão Pulmonar Aguda , Edema Pulmonar , Animais , Humanos , Camundongos , Células A549 , Lesão Pulmonar Aguda/induzido quimicamente , Canais Epiteliais de Sódio/genética , Lipopolissacarídeos
20.
Macromol Rapid Commun ; 44(22): e2300420, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37775102

RESUMO

Tactile sensing is required for electronic skin and intelligent robots to function properly. However, the dielectric layer's poor structural compressibility in conventional pressure sensors results in a limited pressure sensing range and low sensitivity. To solve this issue, a flexible pressure sensor with a crocodile-inspired fillable gradient structure is provided. The fillable gradient structure and grooves in the pressure sensor accommodate the deformed microstructure that permits the enhancement of the media layer compressibility via COMSOL finite element simulation and optimization. The pressure sensor exhibits a high sensitivity of up to 0.97 k Pa-1 (0-4 kPa), a wide pressure detection range (7 Pa-380 kPa), and outstanding repeatability. The sensor can detect Morse code, robotic grabbing, and human motion monitoring. As a result, flexible sensors with a bionic fillable gradient structure pave the way for wearable devices and offer a novel method for achieving highly precise tactile perception.


Assuntos
Dispositivos Eletrônicos Vestíveis , Humanos , Pressão , Biônica/métodos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA