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1.
Nat Methods ; 21(4): 692-702, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38443508

RESUMO

The serotonergic system plays important roles in both physiological and pathological processes, and is a therapeutic target for many psychiatric disorders. Although several genetically encoded GFP-based serotonin (5-HT) sensors were recently developed, their sensitivities and spectral profiles are relatively limited. To overcome these limitations, we optimized green fluorescent G-protein-coupled receptor (GPCR)-activation-based 5-HT (GRAB5-HT) sensors and developed a red fluorescent GRAB5-HT sensor. These sensors exhibit excellent cell surface trafficking and high specificity, sensitivity and spatiotemporal resolution, making them suitable for monitoring 5-HT dynamics in vivo. Besides recording subcortical 5-HT release in freely moving mice, we observed both uniform and gradient 5-HT release in the mouse dorsal cortex with mesoscopic imaging. Finally, we performed dual-color imaging and observed seizure-induced waves of 5-HT release throughout the cortex following calcium and endocannabinoid waves. In summary, these 5-HT sensors can offer valuable insights regarding the serotonergic system in both health and disease.


Assuntos
Receptores Acoplados a Proteínas G , Serotonina , Humanos , Camundongos , Animais , Serotonina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Córtex Cerebral/metabolismo
2.
Nat Methods ; 21(4): 680-691, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38036855

RESUMO

Dopamine (DA) plays multiple roles in a wide range of physiological and pathological processes via a large network of dopaminergic projections. To dissect the spatiotemporal dynamics of DA release in both dense and sparsely innervated brain regions, we developed a series of green and red fluorescent G-protein-coupled receptor activation-based DA (GRABDA) sensors using a variety of DA receptor subtypes. These sensors have high sensitivity, selectivity and signal-to-noise ratio with subsecond response kinetics and the ability to detect a wide range of DA concentrations. We then used these sensors in mice to measure both optogenetically evoked and behaviorally relevant DA release while measuring neurochemical signaling in the nucleus accumbens, amygdala and cortex. Using these sensors, we also detected spatially resolved heterogeneous cortical DA release in mice performing various behaviors. These next-generation GRABDA sensors provide a robust set of tools for imaging dopaminergic activity under a variety of physiological and pathological conditions.


Assuntos
Dopamina , Núcleo Accumbens , Camundongos , Animais , Núcleo Accumbens/fisiologia , Receptores Dopaminérgicos , Encéfalo , Receptores Acoplados a Proteínas G
3.
J Neurochem ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468468

RESUMO

Depressive disorders are a common and debilitating form of mental illness with significant impacts on individuals and society. Despite the high prevalence, the underlying causes and mechanisms of depressive disorders are still poorly understood. Neurochemical systems, including serotonin, norepinephrine, and dopamine, have been implicated in the development and perpetuation of depressive symptoms. Current treatments for depression target these neuromodulator systems, but there is a need for a better understanding of their role in order to develop more effective treatments. Monitoring neurochemical dynamics during depressive symptoms is crucial for gaining a better a understanding of their involvement in depressive disorders. Genetically encoded sensors have emerged recently that offer high spatial-temporal resolution and the ability to monitor neurochemical dynamics in real time. This review explores the neurochemical systems involved in depression and discusses the applications and limitations of current monitoring tools for neurochemical dynamics. It also highlights the potential of genetically encoded sensors for better characterizing neurochemical dynamics in depression-related behaviors. Furthermore, potential improvements to current sensors are discussed in order to meet the requirements of depression research.

4.
Small ; : e2310082, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38470193

RESUMO

Electrochemical conversion of nitrate, a prevalent water pollutant, to ammonia (NH3 ) is a delocalized and green path for NH3 production. Despite the existence of different nitrate reduction pathways, selectively directing the reaction pathway on the road to NH3 is now hindered by the absence of efficient catalysts. Single-atom catalysts (SACs) are extensively investigated in a wide range of catalytic processes. However, their application in electrocatalytic nitrate reduction reaction (NO3 - RR) to NH3 is infrequent, mostly due to their pronounced inclination toward hydrogen evolution reaction (HER). Here, Ni single atoms on the electrochemically active carrier boron, nitrogen doped-graphene (BNG) matrix to modulate the atomic coordination structure through a boron-spanning strategy to enhance the performance of NO3 - RR is designed. Density functional theory (DFT) study proposes that BNG supports with ionic characteristics, offer a surplus electric field effect as compared to N-doped graphene, which can ease the nitrate adsorption. Consistent with the theoretical studies, the as-obtained NiSA@BNG shows higher catalytic activity with a maximal NH3 yield rate of 168 µg h-1  cm-2 along with Faradaic efficiency of 95% and promising electrochemical stability. This study reveals novel ways to rationally fabricate SACs' atomic coordination structure with tunable electronic properties to enhance electrocatalytic performance.

5.
Opt Lett ; 49(11): 2942-2945, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824298

RESUMO

In this Letter, an optically transparent and broadband absorber designed using a multi-objective genetic algorithm (MOGA) is proposed. The absorption of the multilayer lossy frequency selective surface-based absorber is calculated by multilayer absorption equations and equivalent circuit models. To solve the problem of the unbalanced structure absorption bandwidth and thickness, an algorithm is used for optimizing the geometric and sheet resistance parameters of the structure. A multilayer and optically transparent absorber with 90% absorption bandwidth covering a frequency range of 2-18 GHz (S-band to Ku-band) is developed based on the MOGA design method with optical transmittance of 60%. Its total thickness consists of a wavelength of only 0.095, and it has high oblique incidence stability, which makes it useful in the stealth technology and transparent electromagnetic shielding applications.

6.
Drug Metab Dispos ; 51(6): 771-781, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36863865

RESUMO

Icaritin (ICT) is a prenylflavonoid derivative that has been approved by National Medical Products Administration for the treatment of hepatocellular carcinoma. This study aims to evaluate the potential inhibitory effect of ICT against cytochrome P450 (CYP) enzymes and to elucidate the inactivation mechanisms. Results showed that ICT inactivated CYP2C9 in a time-, concentration-, and NADPH-dependent manner with Ki = 1.896 µM, Kinact = 0.02298 minutes-1, and Kinact/Ki = 12 minutes-1 mM-1, whereas the activities of other CYP isozymes was minimally affected. Additionally, the presence of CYP2C9 competitive inhibitor, sulfaphenazole, superoxide dismutase/catalase system, and GSH all protected CYP2C9 from ICT-induced activity loss. Moreover, the activity loss was neither recovered by washing the ICT-CYP2C9 preincubation mixture nor the addition of potassium ferricyanide. These results, collectively, implied the underlying inactivation mechanism involved the covalent binding of ICT to the apoprotein and/or the prosthetic heme of CYP2C9. Furthermore, an ICT-quinone methide (QM)-derived GSH adduct was identified, and human glutathione S-transferases (GST) isozymes GSTA1-1, GSTM1-1, and GSTP1-1 were shown to be substantially involved in the detoxification of ICT-QM. Interestingly, our systematic molecular modeling work predicted that ICT-QM was covalently bound to C216, a cysteine residue located in the F-G loop downstream of substrate recognition site (SRS) 2 in CYP2C9. The sequential molecular dynamics simulation confirmed the binding to C216 induced a conformational change in the active catalytic center of CYP2C9. Lastly, the potential risks of clinical drug-drug interactions triggered by ICT as a perpetrator were extrapolated. In summary, this work confirmed that ICT was an inactivator of CYP2C9. SIGNIFICANCE STATEMENT: This study is the first to report the time-dependent inhibition of CYP2C9 by icaritin (ICT) and the intrinsic molecular mechanism behind it. Experimental data indicated that the inactivation was via irreversible covalent binding of ICT-quinone methide to CYP2C9, while molecular modeling analysis provided additional evidence by predicting C216 as the key binding site which influenced the structural confirmation of CYP2C9's catalytic center. These findings suggest the potential of drug-drug interactions when ICT is co-administered with CYP2C9 substrates clinically.


Assuntos
Sistema Enzimático do Citocromo P-450 , Isoenzimas , Humanos , Citocromo P-450 CYP2C9 , Sistema Enzimático do Citocromo P-450/metabolismo
7.
Chem Res Toxicol ; 36(9): 1483-1494, 2023 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-37622730

RESUMO

Genipin (GP) is the reactive aglycone of geniposide, the main component of traditional Chinese medicine Gardeniae Fructus (GF). The covalent binding of GP to cellular proteins is suspected to be responsible for GF-induced hepatotoxicity and inhibits drug-metabolizing enzyme activity, although the mechanisms remain to be clarified. In this study, the mechanisms of GP-induced human hepatic P450 inactivation were systemically investigated. Results showed that GP inhibited all tested P450 isoforms via distinct mechanisms. CYP2C19 was directly and irreversibly inactivated without time dependency. CYP1A2, CYP2C9, CYP2D6, and CYP3A4 T (testosterone as substrate) showed time-dependent and mixed-type inactivation, while CYP2B6, CYP2C8, and CYP3A4 M (midazolam as substrate) showed time-dependent and irreversible inactivation. For CYP3A4 inactivation, the kinact/KI values in the presence or absence of NADPH were 0.26 or 0.16 min-1 mM-1 for the M site and 0.62 or 0.27 min-1 mM-1 for the T site. Ketoconazole and glutathione (GSH) both attenuated CYP3A4 inactivation, suggesting an active site occupation- and reactive metabolite-mediated inactivation mechanism. Moreover, the in vitro and in vivo formation of a P450-dependent GP-S-GSH conjugate indicated the involvement of metabolic activation and thiol residues binding in GP-induced enzyme inactivation. Lastly, molecular docking analysis simulated potential binding sites and modes of GP association with CYP2C19 and CYP3A4. We propose that direct covalent binding and metabolic activation mediate GP-induced P450 inactivation and alert readers to potential risk factors for GP-related clinical drug-drug interactions.


Assuntos
Citocromo P-450 CYP3A , Gardenia , Humanos , Citocromo P-450 CYP2C19 , Simulação de Acoplamento Molecular , Sistema Enzimático do Citocromo P-450
8.
ORL J Otorhinolaryngol Relat Spec ; 85(3): 156-162, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37075713

RESUMO

INTRODUCTION: Spontaneous cerebrospinal fluid rhinorrhea (SCSFR) is the most common type of cerebrospinal fluid leakage and may cause serious cerebral complications. The aim of this research was to investigate the relationship between the degree of pneumatization variants of the paranasal sinus and skull base and the incidence of SCSFR. METHODS: In total, 131 patients with SCSFR were analyzed, and 50 patients suffering from the nasal septal deviation were selected as controls. The pneumatization of the paranasal sinus and skull base was observed by CT scan. RESULTS: Among the 137 fistulas, 55 (40.15%) were found in the ethmoid sinus. The incidences of Onodi cells (27.27 vs. 8%) and type 3 lateral recess of the sphenoid sinus (LRSS, 70.37 vs. 22%) in the SCSFR subgroups were significantly higher than those in the control group (p < 0.05). Moreover, the occurrence of SCSFR was linearly correlated with the classification of Onodi cells and LRSS (p < 0.05). There was no significant difference in the incidence of frontal cells, anterior clinoid process pneumatization, and posterior clinoid process pneumatization between the SCSFR patients and the controls. CONCLUSION: The most common site of SCSFR is the ethmoid sinus. The excessive pneumatization of the Onodi cell and LRSS increases the risk for the occurrence of SCSFR in the ethmoid sinus and sphenoid sinus, respectively. The possible association between the paranasal sinus ontogeny and SCSFR pathophysiology needs further studies.


Assuntos
Rinorreia de Líquido Cefalorraquidiano , Seios Paranasais , Humanos , Rinorreia de Líquido Cefalorraquidiano/diagnóstico por imagem , Estudos de Casos e Controles , Seios Paranasais/diagnóstico por imagem , Seio Esfenoidal/diagnóstico por imagem , Base do Crânio/diagnóstico por imagem
9.
Sensors (Basel) ; 23(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37420814

RESUMO

A low-profile broadband dual-polarized antenna is investigated for base station applications. It consists of two orthogonal dipoles, fork-shaped feeding lines, an artificial magnetic conductor (AMC), and parasitic strips. By utilizing the Brillouin dispersion diagram, the AMC is designed as the antenna reflector. It has a wide in-phase reflection bandwidth of 54.7% (1.54-2.70 GHz) and a surface-wave bound range of 0-2.65 GHz. This design effectively reduces the antenna profile by over 50% compared to traditional antennas without an AMC. For demonstration, a prototype is fabricated for 2G/3G/LTE base station applications. Good agreement between the simulations and measurements is observed. The measured -10-dB impedance bandwidth of our antenna is 55.4% (1.58-2.79 GHz), with a stable gain of 9.5 dBi and a high isolation of more than 30 dB across the impedance passband. As a result, this antenna is an excellent candidate for miniaturized base station antenna applications.


Assuntos
Utensílios Domésticos , Impedância Elétrica
10.
Opt Express ; 30(22): 40515-40530, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36298983

RESUMO

Topological photonics has become a new and fascinating area in recent years, which enables electromagnetic waves to propagate with negligible backscattering and excellent robustness even when encountering sharp corners or defects. But the flexible tunability of edge and corner states is challenging once the topological photonic crystals (PhCs) have been fabricated. In this paper, we propose a new all-dielectric PhC with C3 symmetry constructed by hexagonal array of petal-like aperture embedded in silicon background. The proposed configuration has much wider energy gap than its triangular counterpart, and hence is suitable for wideband and high-capacity applications. When the apertures are filled with liquid crystals (LCs), the topologically-protected edge and corner states can be regulated through changing the refractive index of the LCs under different bias voltages. Moreover, the robustness of topological protection of edge and corner states is further demonstrated. This is the first demonstration of LC based tunable valley higher-order photonic topological insulator. The tunability of the proposed topological PhCs may be beneficial for development of tunable optical waveguides, reconfigurable topological microcavities, and other intelligent topological optical/terahertz devices.

11.
Fish Shellfish Immunol ; 131: 570-581, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36257557

RESUMO

Nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome is an important inflammasome in mammals, which is of great significance to eliminate pathogens. However, the research of the NLRP3 inflammasome in teleost is limited. Tetraodon nigroviridis has the characteristics of small genome and easy feeding, which can be used as a model for the study of fish immune function. In present study, three NLRP3 inflammasome component genes (NLRP3, ASC and caspase-1) in T. nigroviridis has been cloned. Real-time fluorescence quantitative PCR showed that TnNLRP3 (T. nigroviridis NLRP3), TnASC (T. nigroviridis ASC) and Tncaspase-1 (T. nigroviridis caspase-1) mRNA in various tissues from health T. nigroviridis were highly expressed in immune-related tissues, such as spleen, gill, head kidney and intestine. After Vibrio parahemolyticus infection, the expression of TnNLRP3, TnASC and Tncaspase-1 mRNA in spleen, gill, head kidney reached a peak at 24 h, and the expression levels of these genes in intestine were the highest at 48 h. After the transfection of TnASC-pAcGFP-N1 monomer GFP plasmid into cos-7 cells, ASC specks, the activation marker of NLRP3 inflammasome, were observed. Bimolecular fluorescence complementarity and fluorescence colocation experiment showed that TnASC and Tncaspase-1 of TnNLRP3 inflammasome were co-located near the cell nucleus, and potentially interacted with each other. NLRP3 inflammasome inducer nigericin and agonist ATP could significantly induce the expression of TnNLRP3, TnASC and Tncaspase-1 mRNA, and activation of NLRP3 inflammasome could promote the generation of mature TnIL-1ß (T. nigroviridis IL-1ß). These results uncover that T. nigroviridis NLRP3 inflammasome could participate in the antibacterial immune response and the generation of mature TnIL-1ß after activation.


Assuntos
Inflamassomos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Interleucina-1beta/genética , Caspase 1/genética , Proteínas de Transporte/metabolismo , RNA Mensageiro , Mamíferos/genética , Mamíferos/metabolismo
12.
Fish Shellfish Immunol ; 120: 102-110, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34737057

RESUMO

Vibrio parahaemolyticus is an important marine pathogen that cause inflammation even death in teleost. It has brought huge economic losses to aquaculture and serious threats to the sustainable development of marine fisheries. Here, we isolated the DNA, RNA, and total flagellin from V. parahaemolyticus, and obtained the primary spleen and head kidney cells (including leukocytes) from Tetraodon nigroviridis. V. parahaemolyticus DNA, RNA, and total flagellin were used to treat the T. nigroviridis primary cells described above. The results show that the nitric oxide (NO) production and respiratory burst response were significantly induced after stimulation with V. parahaemolyticus total flagellin in T. nigroviridis head kidney and spleen cells. And total flagellin could promote the gene expression and protein production of IL-1ß in T. nigroviridis leukocytes. T. nigroviridis TLR5M (TnTLR5M) and TLR5S (TnTLR5S) ORF sequences were obtained as the main recognition receptor for flagellin. Real-time fluorescent quantitative PCR (qRT-PCR) was performed to detect the expression of pattern recognition receptor TnTLR5M and TnTLR5S, the important signal molecule of inflammatory system TnMyD88 and TnTRAF6, and inflammatory cytokines TnIL-1ß and TnIFN-γ2. The results show that there were a significant upregulation after challenge with V. parahaemolyticus total flagellin. We further demonstrated that the total flagellin of V. parahaemolyticus could activate the luciferase activity of the NF-κB reporter gene mediated by TnTLR5M. Overall, our results suggest that V. parahaemolyticus total flagellin activated the NO production, respiratory burst response, and inflammatory cytokines expressions, such as TnIL-1ß and TnIFN-γ2, through the TnTLR5M-NF-κB signaling pathway in T. nigroviridis.


Assuntos
Flagelina , Tetraodontiformes , Vibrio parahaemolyticus , Animais , Citocinas/imunologia , Proteínas de Peixes/genética , Flagelina/imunologia , Interferon gama/imunologia , Interleucina-1beta/imunologia , NF-kappa B/genética , Tetraodontiformes/imunologia , Tetraodontiformes/microbiologia , Receptor 5 Toll-Like/genética , Vibrio parahaemolyticus/imunologia
13.
Proc Natl Acad Sci U S A ; 116(17): 8370-8379, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30971491

RESUMO

Metabotropic GABAB receptors mediate a significant fraction of inhibitory neurotransmission in the brain. Native GABAB receptor complexes contain the principal subunits GABAB1 and GABAB2, which form an obligate heterodimer, and auxiliary subunits, known as potassium channel tetramerization domain-containing proteins (KCTDs). KCTDs interact with GABAB receptors and modify the kinetics of GABAB receptor signaling. Little is known about the molecular mechanism governing the direct association and functional coupling of GABAB receptors with these auxiliary proteins. Here, we describe the high-resolution structure of the KCTD16 oligomerization domain in complex with part of the GABAB2 receptor. A single GABAB2 C-terminal peptide is bound to the interior of an open pentamer formed by the oligomerization domain of five KCTD16 subunits. Mutation of specific amino acids identified in the structure of the GABAB2-KCTD16 interface disrupted both the biochemical association and functional modulation of GABAB receptors and G protein-activated inwardly rectifying K+ channel (GIRK) channels. These interfacial residues are conserved among KCTDs, suggesting a common mode of KCTD interaction with GABAB receptors. Defining the binding interface of GABAB receptor and KCTD reveals a potential regulatory site for modulating GABAB-receptor function in the brain.


Assuntos
Peptídeos e Proteínas de Sinalização Intracelular , Proteínas do Tecido Nervoso , Receptores de GABA-B , Sítios de Ligação/genética , Cristalografia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Modelos Moleculares , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Ligação Proteica/genética , Receptores de GABA-B/química , Receptores de GABA-B/genética , Receptores de GABA-B/metabolismo , Transdução de Sinais/genética
14.
Sensors (Basel) ; 22(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36502245

RESUMO

This paper presents the development of a visual-perception system on a dual-arm mobile robot for human-robot interaction. This visual system integrates three subsystems. Hand gesture recognition is utilized to trigger human-robot interaction. Engagement and intention of the participants are detected and quantified through a cognitive system. Visual servoing uses YOLO to identify the object to be tracked and hybrid, model-based tracking to follow the object's geometry. The proposed visual-perception system is implemented in the developed dual-arm mobile robot, and experiments are conducted to validate the proposed method's effects on human-robot interaction applications.


Assuntos
Robótica , Humanos , Algoritmos , Percepção Visual
15.
Clin Otolaryngol ; 47(6): 664-671, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36073732

RESUMO

OBJECTIVE: To investigate the associations between weekly alcohol consumption and the risk and surgical outcome of Chronic Rhinosinusitis (CRS). DESIGN: A case-control study. SETTING AND PARTICIPANTS: The study population consisted of 1095 CRS patients and 909 healthy collected from the first affiliated hospital of Zhengzhou University between May 2018 and December 2019. MAIN OUTCOME MEASURES: Unconditional multivariate logistic regression analysis and Cox proportional hazards regression analysis were performed to estimate the association of alcohol consumption with the risk and surgical outcomes of CRS. Odds ratios (OR) or hazard ratio (HR) with 95% confidence intervals (CI) were calculated separately. The Kruskal-Wallis test was used to explore the possible molecular mechanisms. RESULTS: As compared with nondrinkers, the multivariable-adjusted OR (95% CI) values of current drinkers consuming 7.5-22 drinks and >22 drinks per week were 2.158 (1.249-3.729) and 5.373 (2.912-9.911), respectively. The rate of mucosal epithelialization after CRS surgery for patients who drank 7.5-22 drinks and >22 drinks per week was lower than that of nondrinkers [HR (95% CI) = 0.487 (0.351-0.675) and 0.252 (0.184-0.346), respectively]. The association of alcohol consumption with the risk and surgical outcome of CRS was dose dependent (p < .01). Alcohol consumption increased the risk of CRS and extended the time of mucosal epithelialization after CRS surgery by possibly increasing serum IgE levels (p < .05). CONCLUSION: Higher alcohol consumption of >7.5 drinks per week was an independent risk factor for CRS and extended the time of mucosal epithelialization after surgery. As a potential underlying mechanism, alcohol consumption increases serum IgE levels.


Assuntos
Consumo de Bebidas Alcoólicas , Imunoglobulina E , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Estudos de Casos e Controles , China/epidemiologia , Humanos , Estudos Prospectivos , Fatores de Risco , Resultado do Tratamento
16.
Am J Physiol Cell Physiol ; 319(3): C569-C578, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32755449

RESUMO

Mutations in connexin 30 (Cx30) are known to cause severe congenital hearing impairment; however, the mechanism by which Cx30 mediates homeostasis of endocochlear gap junctions is unclear. We used a gene deletion mouse model to explore the mechanisms of Cx30 in preventing hearing loss. Our results suggest that despite severe loss of the auditory brain-stem response and endocochlear potential at postnatal day 18, Cx30-/- mice only show sporadic loss of the outer hair cells. This inconsistency in the time course and severity of hearing and hair cell losses in Cx30-/- mice might be explained, in part, by an increase in reactive oxygen species generation beginning at postnatal day 10. The expression of oxidative stress genes was increased in Cx30-/- mice in the stria vascularis, spiral ligament, and organ of Corti. Furthermore, Cx30 deficiency caused mitochondrial dysfunction at postnatal day 18, as assessed by decreased ATP levels and decreased expression of mitochondrial complex I proteins, especially in the stria vascularis. Proteomic analysis further identified 444 proteins that were dysregulated in Cx30-/- mice, including several that are involved in mitochondria electron transport, ATP synthesis, or ion transport. Additionally, proapoptotic proteins, including Bax, Bad, and caspase-3, were upregulated at postnatal day 18, providing a molecular basis to explain the loss of hearing that occurs before hair cell loss. Therefore, our results are consistent with an environment of oxidative stress and mitochondrial damage in the cochlea of Cx30-/- mice that is coincident with hearing loss but precedes hair cell loss.


Assuntos
Morte Celular/fisiologia , Conexinas/genética , Perda Auditiva Neurossensorial/metabolismo , Perda Auditiva/genética , Animais , Cóclea/metabolismo , Junções Comunicantes/metabolismo , Camundongos Knockout , Proteômica
17.
Fish Shellfish Immunol ; 101: 159-167, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32194248

RESUMO

Inhibitor of nuclear factor kappa-B kinase subunit alpha (IKKα) plays crucial roles in regulating activation of nuclear factor kappa-B (NF-κB) in response to pathogens infections. Here, we cloned and identified IKKα gene of orange-spotted grouper (Epinephelus coioides), named as EcIKKα. The gene transcript contained a 2262 bp open reading frame, which encoded 753 amino acids. The typically conserved IKKα structure, including serine kinase domain (KD), leucine chain (LZ) structure, helix-loop-helix (HLH) motif and IKKß-NEMO-binding domain, was identified in EcIKKα. Phylogenetic analysis suggested that EcIKKα had the closest relationship with large yellow croaker (Larimichthy crocea) IKKα. Ecikkα was ubiquitously expressed in all tissues tested and the highest expression level was in ovary. After lipopolysaccharide (LPS), flagellin, polyinosinic-polycytidylic acid (poly I:C), polyadenylic-polyuridylic acid (poly A:U), and Vibrio parahaemolyticus stimulation, the expression of Ecikkα increased in grouper spleen (GS) cells. In the luciferase assay, NF-κB-luc activity was significantly up-regulated when human embryonic kidney 293T (HEK 293T) cells were transfected with EcIKKα plasmid. Moreover, overexpression of EcIKKα significantly increased LPS- and flagellin-induced proinflammatory cytokines (interleukin-6 (il-6) and tumor necrosis factor-α (tnf-α)) expression, but did not significantly affect poly I:C- and poly A:U-induced cytokines (il-6 and tnf-α) expression. Overall, these results suggested that EcIKKα functions like that of mammals to activate NF-κB, and it could be involved in host defense against invading pathogens.


Assuntos
Bass/genética , Bass/imunologia , Doenças dos Peixes/imunologia , Regulação da Expressão Gênica/imunologia , Quinase I-kappa B/genética , Quinase I-kappa B/imunologia , Imunidade Inata/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Citocinas/metabolismo , Proteínas de Peixes/química , Proteínas de Peixes/genética , Proteínas de Peixes/imunologia , Expressão Gênica/imunologia , Perfilação da Expressão Gênica/veterinária , Quinase I-kappa B/química , NF-kappa B/metabolismo , Moléculas com Motivos Associados a Patógenos/metabolismo , Filogenia , Alinhamento de Sequência/veterinária , Vibrioses/imunologia , Vibrioses/veterinária , Vibrio parahaemolyticus/fisiologia
18.
BMC Bioinformatics ; 20(1): 355, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31234779

RESUMO

BACKGROUND: Essential proteins are distinctly important for an organism's survival and development and crucial to disease analysis and drug design as well. Large-scale protein-protein interaction (PPI) data sets exist in Saccharomyces cerevisiae, which provides us with a valuable opportunity to predict identify essential proteins from PPI networks. Many network topology-based computational methods have been designed to detect essential proteins. However, these methods are limited by the completeness of available PPI data. To break out of these restraints, some computational methods have been proposed by integrating PPI networks and multi-source biological data. Despite the progress in the research of multiple data fusion, it is still challenging to improve the prediction accuracy of the computational methods. RESULTS: In this paper, we design a novel iterative model for essential proteins prediction, named Randomly Walking in the Heterogeneous Network (RWHN). In RWHN, a weighted protein-protein interaction network and a domain-domain association network are constructed according to the original PPI network and the known protein-domain association network, firstly. And then, we establish a new heterogeneous matrix by combining the two constructed networks with the protein-domain association network. Based on the heterogeneous matrix, a transition probability matrix is established by normalized operation. Finally, an improved PageRank algorithm is adopted on the heterogeneous network for essential proteins prediction. In order to eliminate the influence of the false negative, information on orthologous proteins and the subcellular localization information of proteins are integrated to initialize the score vector of proteins. In RWHN, the topology, conservative and functional features of essential proteins are all taken into account in the prediction process. The experimental results show that RWHN obviously exceeds in predicting essential proteins ten other competing methods. CONCLUSIONS: We demonstrated that integrating multi-source data into a heterogeneous network can preserve the complex relationship among multiple biological data and improve the prediction accuracy of essential proteins. RWHN, our proposed method, is effective for the prediction of essential proteins.


Assuntos
Mapeamento de Interação de Proteínas/métodos , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Algoritmos , Domínios Proteicos , Mapas de Interação de Proteínas , Proteínas de Saccharomyces cerevisiae/química
19.
BMC Cancer ; 19(1): 104, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30678643

RESUMO

BACKGROUND: microRNA (miR)-342-3p is frequently dysregulated in human cancers. In the present study, we aimed to explore the expression, prognostic significance, and biological relevance of miR-342-3p in nasopharyngeal carcinoma (NPC). METHODS: We examined miR-342-3p expression in 79 paired NPC specimens and corresponding normal tissues and analyzed its prognostic impact on overall survival of NPC patients. Gain- and loss-of-function experiments were conducted to determine the biological roles of miR-342-3p. RESULTS: Compared with matched normal nasopharyngeal tissues, miR-342-3p was significantly downregulated in NPC (P = 0.0038). Low miR-342-3p expression was significantly correlated with reduced overall survival (P = 0.0084). Ectopic expression of miR-342-3p significantly suppressed proliferation, colony formation, and invasion of NPC cells. In contrast, depletion of miR-342-3p facilitated NPC cell proliferation and invasion. In vivo xenograft studies confirmed that overexpression of miR-342-3p restrained the growth of NPC xenograft tumors. Mechanistically, FOXQ1 served as a functional target of miR-342-3p. There was a significantly negative correlation between miR-342-3p and FOXQ1 expression (r = - 0.487, P = 0.004) in NPC specimens. Overexpression of FOXQ1 rescued the inhibitory effects of miR-342-3p on NPC cell growth and invasion. CONCLUSIONS: miR-342-3p downregulation predicts poor prognosis in NPC patients and shows suppressive activity against NPC growth and invasion through repression of FOXQ1. Restoration of miR-342-3p may represent a potential therapeutic strategy for NPC.


Assuntos
Fatores de Transcrição Forkhead/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , MicroRNAs/metabolismo , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Mutação , Carcinoma Nasofaríngeo/mortalidade , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Invasividade Neoplásica , Prognóstico , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Alcohol Clin Exp Res ; 43(6): 1180-1190, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30964201

RESUMO

BACKGROUND: Alcohol alters synaptic transmission in the brain. The N-methyl-D-aspartate (NMDA) receptor (NMDAR), a subtype of glutamate-gated ion channel, is an important synaptic target of alcohol in the brain. We and others have previously identified 4 alcohol-sensitive positions in the third and fourth membrane-associated (M) domains, designated M31-2 and M41-2 , of the GluN1, GluN2A, and GluN2B NMDAR subunits. In the present study, we tested whether the corresponding positions in the GluN2C subunit also regulate alcohol sensitivity and ion channel gating. METHODS: We performed alanine- and tryptophan-scanning mutagenesis in the GluN2C subunit followed by expression in HEK 293 cells and electrophysiological patch-clamp recording. RESULTS: Alanine substitution at the M31 (F634) and M41-2 (M821 and M823) positions did not alter ethanol (EtOH) sensitivity, whereas substitution of alanine at the M32 position (F635) yielded nonfunctional receptors. Tryptophan substitution at the M31-2 positions did not change EtOH sensitivity, whereas tryptophan substitution at the M41 position increased, and at the M42 position decreased, EtOH sensitivity. The increased EtOH sensitivity of the tryptophan mutant at M41 is in marked contrast to previous results observed in the GluN2A and GluN2B subunits. In addition, this mutant exhibited increased desensitization, but to a much lesser extent compared to the corresponding mutations in GluN2A and GluN2B. A series of mutations at M41 altered EtOH sensitivity, glutamate potency, and desensitization. Seven amino acid substitutions (of 15 tested) at this position yielded nonfunctional receptors. Among the remaining mutants at M41 , EtOH sensitivity was not significantly correlated with hydrophobicity, molecular volume, or polarity of the substituent, or with glutamate EC50 values, but was correlated with maximal steady-state-to-peak current ratio, a measure of desensitization. CONCLUSIONS: The identity and characteristics of alcohol-sensitive positions in the GluN2C subunit differ from those previously reported for GluN2A and GluN2B subunits, despite the high homology among these subunits.


Assuntos
Depressores do Sistema Nervoso Central/efeitos adversos , Etanol/efeitos adversos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Células HEK293 , Humanos , Mutagênese Sítio-Dirigida , Receptores de N-Metil-D-Aspartato/genética
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