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1.
EMBO J ; 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39134659

RESUMEN

Sex determination in animals is not only determined by karyotype but can also be modulated by environmental cues like temperature via unclear transduction mechanisms. Moreover, in contrast to earlier views that sex may exclusively be determined by either karyotype or temperature, recent observations suggest that these factors rather co-regulate sex, posing another mechanistic mystery. Here, we discovered that certain wild-isolated and mutant C. elegans strains displayed genotypic germline sex determination (GGSD), but with a temperature-override mechanism. Further, we found that BiP, an ER chaperone, transduces temperature information into a germline sex-governing signal, thereby enabling the coexistence of GGSD and temperature-dependent germline sex determination (TGSD). At the molecular level, increased ER protein-folding requirements upon increased temperatures lead to BiP sequestration, resulting in ERAD-dependent degradation of the oocyte fate-driving factor, TRA-2, thus promoting male germline fate. Remarkably, experimentally manipulating BiP or TRA-2 expression allows to switch between GGSD and TGSD. Physiologically, TGSD allows C. elegans hermaphrodites to maintain brood size at warmer temperatures. Moreover, BiP can also influence germline sex determination in a different, non-hermaphroditic nematode species. Collectively, our findings identify thermosensitive BiP as a conserved temperature sensor in TGSD, and provide mechanistic insights into the transition between GGSD and TGSD.

2.
J Cell Sci ; 134(18)2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34435628

RESUMEN

Selectins and integrins are key players in the adhesion and signaling cascade that recruits leukocytes to inflamed tissues. Selectin binding induces ß2 integrin binding to slow leukocyte rolling. Here, a micropipette was used to characterize neutrophil adhesion to E-selectin and intercellular adhesion molecule-1 (ICAM-1) at room temperature. The time-dependent adhesion frequency displayed two-stage kinetics, with an E-selectin-mediated fast increase to a low plateau followed by a slow increase to a high plateau mediated by intermediate-affinity binding of integrin αLß2 to ICAM-1. The αLß2 activation required more than 5 s contact to E-selectin and spleen tyrosine kinase (Syk) activity. A multi-zone channel was used to analyze αLß2 activation by P-selectin in separate zones of receptors or antibodies, finding an inverse relationship between the rolling velocity on ICAM-1 and P-selectin dose, and a P-selectin dose-dependent change from bent to extended conformations with a closed headpiece that was faster at 37°C than at room temperature. Activation of αLß2 exhibited different levels of cooperativity and persistent times depending on the strength and duration of selectin stimulation. These results define the precise timing and kinetics of intermediate activation of αLß2 by E- and P-selectins.


Asunto(s)
Selectina E , Antígeno-1 Asociado a Función de Linfocito , Antígenos CD18 , Adhesión Celular , Selectina E/genética , Selectina E/metabolismo , Molécula 1 de Adhesión Intercelular , Cinética , Neutrófilos/metabolismo , Selectina-P
3.
Horm Metab Res ; 55(6): 420-425, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36599457

RESUMEN

Pancreatic cancer (PC) has the lowest survival rate and the highest mortality rate among all cancers due to lack of effective treatments. The objective of the current study was to identify potential therapeutic targets in PC. Three transcriptome datasets, namely GSE62452, GSE46234, and GSE101448, were analyzed for differentially expressed genes (DEGs) between cancer and normal samples. Several bioinformatics methods, including functional analysis, pathway enrichment, hub genes, and drugs were used to screen therapeutic targets for PC. Fisher's exact test was used to analyze functional enrichments. To screen DEGs, the paired t-test was employed. The statistical significance was considered at p <0.05. Overall, 60 DEGs were detected. Functional enrichment analysis revealed enrichment of the DEGs in "multicellular organismal process", "metabolic process", "cell communication", and "enzyme regulator activity". Pathway analysis demonstrated that the DEGs were primarily related to "Glycolipid metabolism", "ECM-receptor interaction", and "pathways in cancer". Five hub genes were examined using the protein-protein interaction (PPI) network. Among these hub genes, 10 known drugs targeted to the CPA1 gene and CLPS gene were found. Overall, CPA1 and CLPS genes, as well as candidate drugs, may be useful for PC in the future.


Asunto(s)
Perfilación de la Expresión Génica , Neoplasias Pancreáticas , Humanos , Perfilación de la Expresión Génica/métodos , Biomarcadores de Tumor/genética , Detección Precoz del Cáncer/métodos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/diagnóstico , Biología Computacional/métodos , Neoplasias Pancreáticas
4.
Org Biomol Chem ; 21(37): 7639-7642, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37682085

RESUMEN

This work describes an environmentally friendly method for the synthesis of benzoxazinones, quinoxalinones and benzothiazoles by the reaction of α-arylglyoxylic acids and ortho-functionalized aniline. In this reaction, no other reagents are needed except for reactants and solvents. The reaction was carried out at a mild temperature of 50 °C with only water and/or carbon dioxide as the by-product. Therefore, the reaction has high practical atom economy. In addition, this strategy could be scaled up to the gram level, and the natural product Cephamandole A could be synthesized on a mass scale.

5.
Ecotoxicol Environ Saf ; 267: 115649, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37913580

RESUMEN

Pesticide resistance inflicts significant economic losses on a global scale each year. To address this pressing issue, substantial efforts have been dedicated to unraveling the resistance mechanisms, particularly the newly discovered microbiota-derived pesticide resistance in recent decades. Previous research has predominantly focused on investigating microbiota-derived pesticide resistance from the perspective of the pest host, associated microbes, and their interactions. However, a gap remains in the quantification of the contribution by the pest host and associated microbes to this resistance. In this study, we investigated the toxicity of phoxim by examining one resistant and one sensitive Delia antiqua strain. We also explored the critical role of associated microbiota and host in conferring phoxim resistance. In addition, we used metaproteomics to compare the proteomic profile of the two D. antiqua strains. Lastly, we investigated the activity of detoxification enzymes in D. antiqua larvae and phoxim-degrading gut microbes, and assessed their respective contributions to phoxim resistance in D. antiqua. The results revealed contributions by D. antiqua and its gut bacteria to phoxim resistance. Metaproteomics showed that the two D. antiqua strains expressed different protein profiles. Detoxifying enzymes including Glutathione S-transferases, carboxylesterases, Superoxide Dismutase, Glutathione Peroxidase, and esterase B1 were overexpressed in the resistant strain and dominated in differentially expressed insect proteins. In addition, organophosphorus hydrolases combined with a group of ABC type transporters were overexpressed in the gut microbiota of resistant D. antiqua compared to the sensitive strain. 85.2% variation of the larval mortality resulting from phoxim treatment could be attributed to the combined effects of proteins from both from gut bacteria and D. antiqua, while the individual contribution of proteins from gut bacteria or D. antiqua alone accounted for less than 10% of the variation in larval mortality caused by phoxim. The activity of the overexpressed insect enzymes and the phoxim-degrading activity of gut bacteria in resistant D. antiqua larvae were further confirmed. This work enhances our understanding of microbiota-derived pesticide resistance and illuminates new strategies for controlling pesticide resistance in the context of insect-microbe mutualism.


Asunto(s)
Microbioma Gastrointestinal , Plaguicidas , Animales , Cebollas , Proteómica , Transportadoras de Casetes de Unión a ATP , Arildialquilfosfatasa , Larva
6.
Anesthesiology ; 136(5): 802-822, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35303056

RESUMEN

BACKGROUND: Slick, a sodium-activated potassium channel, has been recently identified in somatosensory pathways, but its functional role is poorly understood. The authors of this study hypothesized that Slick is involved in processing sensations of pain and itch. METHODS: Immunostaining, in situ hybridization, Western blot, and real-time quantitative reverse transcription polymerase chain reaction were used to investigate the expression of Slick in dorsal root ganglia and the spinal cord. Mice lacking Slick globally (Slick-/-) or conditionally in neurons of the spinal dorsal horn (Lbx1-Slick-/-) were assessed in behavioral models. RESULTS: The authors found Slick to be enriched in nociceptive Aδ-fibers and in populations of interneurons in the spinal dorsal horn. Slick-/- mice, but not Lbx1-Slick-/- mice, showed enhanced responses to noxious heat in the hot plate and tail-immersion tests. Both Slick-/- and Lbx1-Slick-/- mice demonstrated prolonged paw licking after capsaicin injection (mean ± SD, 45.6 ± 30.1 s [95% CI, 19.8 to 71.4]; and 13.1 ± 16.1 s [95% CI, 1.8 to 28.0]; P = 0.006 [Slick-/- {n = 8} and wild-type {n = 7}, respectively]), which was paralleled by increased phosphorylation of the neuronal activity marker extracellular signal-regulated kinase in the spinal cord. In the spinal dorsal horn, Slick is colocalized with somatostatin receptor 2 (SSTR2), and intrathecal preadministration of the SSTR2 antagonist CYN-154806 prevented increased capsaicin-induced licking in Slick-/- and Lbx1-Slick-/- mice. Moreover, scratching after intrathecal delivery of the somatostatin analog octreotide was considerably reduced in Slick-/- and Lbx1-Slick-/- mice (Slick-/- [n = 8]: 6.1 ± 6.7 bouts [95% CI, 0.6 to 11.7]; wild-type [n =8]: 47.4 ± 51.1 bouts [95% CI, 4.8 to 90.2]; P = 0.039). CONCLUSIONS: Slick expressed in a subset of sensory neurons modulates heat-induced pain, while Slick expressed in spinal cord interneurons inhibits capsaicin-induced pain but facilitates somatostatin-induced itch.


Asunto(s)
Capsaicina , Células del Asta Posterior , Animales , Capsaicina/efectos adversos , Capsaicina/metabolismo , Ganglios Espinales/metabolismo , Ratones , Dolor , Células del Asta Posterior/metabolismo , Canales de Potasio , Prurito/inducido químicamente , Células Receptoras Sensoriales/metabolismo , Canales de Sodio , Somatostatina/efectos adversos , Somatostatina/metabolismo , Médula Espinal/metabolismo
7.
Analyst ; 147(6): 1222-1235, 2022 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-35212697

RESUMEN

Microvascular thrombosis and inflammation (thromboinflammation) are major causes of morbidity and mortality in critically ill patients with limited therapeutic options. Platelets are central to thromboinflammation, and microvascular platelet thrombi are highly effective at recruiting and activating leukocytes at sites of endothelial injury. Whilst parallel-plate flow chambers, microslides and straight microchannel assays have been widely used to recapitulate leukocyte adhesive behavior on 2-dimensional (2D) surfaces, none of these methods achieve high fidelity 3-dimensional (3D) geometries emulating microvascular platelet thrombi. As a result, the role of hydrodynamic factors in regulating leukocyte interactions with platelet thrombi remains ill-defined. Here, we report a microfluidic post model that allows visualization and analysis of neutrophil-platelet interactions in a 3D flow field. We have utilized the unique mechanosensitive features of platelets to enable selective micropatterning of the 3D posts with human or mouse platelets. By modulating the activation status of platelets, our method enables precise control of platelet surface reactivity and neutrophil recruitment. In addition, our microfluidic post assay accurately recapitulated the rolling versus stationary adhesion behavior of single neutrophils and demonstrated the efficacy of the P-selectin and Mac-1 blocking antibodies to reduce neutrophil recruitment and stationary adhesion, respectively. Moreover, the geometry of posts had a major influence on the efficiency of neutrophil recruitment and adhesion stability. This new post method highlights the importance of platelet 3D geometries in facilitating efficient, localized neutrophil recruitment. These findings have potentially important implications for the potent proinflammatory function of microvascular platelet thrombi.


Asunto(s)
Plaquetas , Trombosis , Animales , Adhesión Celular , Humanos , Inflamación , Leucocitos , Ratones , Microfluídica , Neutrófilos
8.
Fish Shellfish Immunol ; 122: 170-180, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35150828

RESUMEN

Glutaminolysis has been proved to play an irreplaceable role in vertebrate immunity, including effects on cytokine production, bacterial killing, and redox homeostasis maintenance. Our previous metabolomics analysis indicated that glutaminolysis metabolic substrates glutamine (Gln) and metabolites glutamate (Glu) were significantly lower in Skin ulceration syndrome (SUS)-diseased Apostichopus japonicus. To further delineate the role of glutaminolysis, we assayed the levels of Gln and Glu. We found that their contents in coelomocytes were decreased, accompanied by an increase in glutathione (GSH) in pathogen-challenged Apostichopus japonicus. Consistently, the mRNA transcripts of three key genes in glutaminolysis (AjASCT2, AjGOT, and AjGCS) were significantly induced. Moreover, the increased MDA and NADPH/NADP + levels in response to pathogen infection indicated that oxidative stress occurs during the immune response. The metabolic regulator AMPKß could regulate glutaminolysis in vertebrates by inducing cells to take up extracellular Gln. To explore the underlying regulatory mechanism behind glutaminolysis that occurred in coelomocytes, the full-length cDNA of AMPKß was identified from A. japonicus (designated as AjAMPKß). AjAMPKß expression was significantly induced in the coelomocytes after pathogen challenge, which was consistent with the expression of key genes of glutaminolysis. A functional assay indicated that AjAMPKß silencing by siRNA transfection could increase the levels of Gln and Glu and depress the production of GSH. Moreover, the expression of glutaminolysis-related genes was significantly inhibited, and the reduction of redox homeostasis indexes (MDA and NADPH/NADP+) was also observed. Contrastingly, AjAMPKß overexpression promoted redox homeostasis balance. Intracellular ROS is mostly responsible for breaking redox homeostasis and leading to oxidative stress, contributing to cell fate changes in immune cells. Exogenous Gln and GSH treatments could significantly reduce ROS level while the AjAMPKß silencing induced the level of ROS and accelerated the necrosis rate. All these results collectively revealed that AjAMPKß could modulate cellular redox homeostasis by affecting the glutaminolysis in A. japonicus.


Asunto(s)
Stichopus , Vibrio , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Homeostasis , Inmunidad Innata/genética , Oxidación-Reducción , Vibrio/fisiología
9.
J Appl Microbiol ; 133(5): 2680-2693, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35543356

RESUMEN

AIM: Oxalic acid (OA) is one of the pathogenic factors of Botrytis cinerea. Trichoderma afroharzianum exerts both antagonistic and oxalate-degrading effects on B. cinerea. This study aimed to investigate the relationship between the elimination of OA by T. afroharzianum and its antagonistic effects on B. cinerea. METHODS AND RESULTS: Reversed-phase high performance liquid chromatogram (RP-HPLC) analysis showed that T. afroharzianum LTR-2 eliminated 10- or 20-mmol/L OA within 120 h, with the degradation being particularly efficient at the concentration of 20 mmol/L. RNA-seq analysis showed that the oxalate decarboxylase (OXDC) gene Toxdc, ß-1,3-exoglucanase gene Tglu and aspartic protease gene Tpro of LTR-2 were significantly upregulated after treatment with 20-mmol/L OA. RT-qPCR analysis showed that under the conditions of confrontation, Toxdc and three cell wall degrading enzyme (CWDE) genes were upregulated before physical contact with B. cinerea. In addition, RT-qPCR analysis showed that OA synthesis in B. cinerea was not significantly affected by LTR-2. CONCLUSIONS: The results revealed a correlation between OA degradation and mycoparasitism in T. afroharzianum when antagonising B. cinerea at the transcriptional level. SIGNIFICANCE AND IMPACT OF THE STUDY: The relationship between OA degradation by T. afroharzianum and its effects against B. cinerea provide a new perspective on the antagonism of T. afroharzianum against B. cinerea. In addition, this study provides theoretical data for the scientific application of T. afroharzianum in the field of biocontrol.


Asunto(s)
Ácido Oxálico , Trichoderma , Ácido Oxálico/metabolismo , Trichoderma/genética , Trichoderma/metabolismo , Enfermedades de las Plantas , Botrytis/genética , Botrytis/metabolismo , Pared Celular/metabolismo , Péptido Hidrolasas/metabolismo
10.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36430212

RESUMEN

Brassica carinata (BBCC, 2n = 34) is commonly known as Ethiopian mustard, Abyssinian mustard, or carinata. Its excellent agronomic traits, including resistance to biotic and abiotic stresses, make it a potential genetic donor for interspecific hybridization. Myzus persicae (green peach aphid, GPA) is one of the most harmful pests of Brassica crops, significantly effecting the yield and quality. However, few aphid-resistant Brassica crop germplasms have been utilized in breeding practices, while the underlying biochemical basis of aphid resistance still remains poorly understood. In this study, we examined the genetic diversity of 75 B. carinata accessions and some plant characteristics that potentially contribute to GPA resistance. Initially, the morphological characterization showed abundant diversity in the phenotypic traits, with the dendrogram indicating that the genetic variation of the 75 accessions ranged from 0.66 to 0.98. A population structure analysis revealed that these accessions could be grouped into two main subpopulations and one admixed group, with the majority of accessions (86.67%) clustering in one subpopulation. Subsequently, there were three GPA-resistant B. carinata accessions, BC13, BC47, and BC51. The electrical penetration graph (EPG) assay detected resistance factors in the leaf mesophyll tissue and xylem. The result demonstrated that the Ethiopian mustard accessions were susceptible when the phloem probing time, the first probe time, and the G-wave time were 20.51-32.51 min, 26.36-55.54 s, and 36.18-47.84 min, respectively. In contrast, resistance of the Ethiopian mustard accessions was observed with the phloem probing time, the first probe time, and G-wave time of 41.18-70.78 min, 181.07-365.85 s, and 18.03-26.37 min, respectively. In addition, the epidermal characters, leaf anatomical structure, glucosinolate composition, defense-related enzyme activities, and callose deposition were compared between the resistant and susceptible accessions. GPA-resistant accessions had denser longitudinal leaf structure, higher wax content on the leaf surface, higher indole glucosinolate level, increased polyphenol oxidase (PPO) activity, and faster callose deposition than the susceptible accessions. This study validates that inherent physical and chemical barriers are evidently crucial factors in the resistance against GPA infestation. This study not only provide new insights into the biochemical basis of GPA resistance but also highlights the GPA-resistant B. carinata germplasm resources for the future accurate genetic improvement of Brassica crops.


Asunto(s)
Áfidos , Animales , Glucosinolatos , Planta de la Mostaza/genética , Etiopía , Fitomejoramiento , Productos Agrícolas , Variación Genética
11.
J Immunol ; 203(3): 760-768, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31201236

RESUMEN

A T cell clone is able to distinguish Ags in the form of peptide-MHC complexes with high specificity and sensitivity; however, how subtle differences in peptide-MHC structures translate to distinct T cell effector functions remains unknown. We hypothesized that mitochondrial positioning and associated calcium responses play an important role in T cell Ag recognition. We engineered a microfluidic system to precisely manipulate and synchronize a large number of cell-cell pairing events, which provided simultaneous real-time signaling imaging and organelle tracking with temporal precision. In addition, we developed image-derived metrics to quantify calcium response and mitochondria movement. Using myelin proteolipid altered peptide ligands and a hybridoma T cell line derived from a mouse model of experimental autoimmune encephalomyelitis, we observed that Ag potency modulates calcium response at the single-cell level. We further developed a partial least squares regression model, which highlighted mitochondrial positioning as a strong predictor of calcium response. The model revealed T cell mitochondria sharply alter direction within minutes following exposure to agonist peptide Ag, changing from accumulation at the immunological synapse to retrograde movement toward the distal end of the T cell body. By quantifying mitochondria movement as a highly dynamic process with rapidly changing phases, our result reconciles conflicting prior reports of mitochondria positioning during T cell Ag recognition. We envision applying this pipeline of methodology to study cell interactions between other immune cell types to reveal important signaling phenomenon that is inaccessible because of data-limited experimental design.


Asunto(s)
Antígenos de Diferenciación de Linfocitos T/inmunología , Linfocitos T CD4-Positivos/inmunología , Calcio/metabolismo , Técnicas Analíticas Microfluídicas/métodos , Mitocondrias/metabolismo , Animales , Línea Celular Tumoral , Encefalomielitis Autoinmune Experimental/inmunología , Humanos , Hibridomas , Ratones , Transducción de Señal/inmunología
12.
Ecotoxicol Environ Saf ; 225: 112785, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34544021

RESUMEN

Neonicotinoids are among the most widely used insecticides worldwide, and as such, have garnered increasing attention from the scientific community in regards to their potentially negative environmental impacts. Recently, the degradability of neonicotinoid in soil has gained more attentions. However, what role soil microbes play in this degradation remains vastly underexplored. In this study, we compared the capacity of soil microbes sampled from different geographic regions and fields to degrade the neonicotinoid insecticide imidacloprid. Additionally, the composition of microbiota having low, middle, and high degradation activity was analyzed via high throughput sequencing. Correlations between microbiota composition and degradation activities were analyzed and reconfirmed. The results showed that the composition of soil microbiota and their degradation activity (ranged from zero to 96.25%) varied significantly between soil samples from different geographic locations. Correlation analysis showed that Paracoccus and Achromobacter bacteria were positively correlated with high degradation activity. Imidacloprid degradation experiments using these bacteria showed that Achromobacter sp. alone exhibited degradation activity reaching and sustaining 100% by day 20 while Paracoccus sp. did not. However, combining these bacteria resulted in increased degradation activity which reached 100% at day 15 relative to that achieved by Achromobacter sp. alone. This study demonstrated the capacity of soil microbes to degrade imidacloprid, and identified two promising bacterial candidates that could be potentially used in future to reduce imidacloprid accumulation in soils.


Asunto(s)
Achromobacter , Insecticidas , Paracoccus , Contaminantes del Suelo , Bacterias , Biodegradación Ambiental , Neonicotinoides , Nitrocompuestos , Suelo , Microbiología del Suelo
13.
Int J Mol Sci ; 22(1)2021 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-33401689

RESUMEN

The sodium-activated potassium channel Slack (KNa1.1, Slo2.2, or Kcnt1) is highly expressed in populations of sensory neurons, where it mediates the sodium-activated potassium current (IKNa) and modulates neuronal activity. Previous studies suggest that Slack is involved in the processing of neuropathic pain. However, mechanisms underlying the regulation of Slack activity in this context are poorly understood. Using whole-cell patch-clamp recordings we found that Slack-mediated IKNa in sensory neurons of mice is reduced after peripheral nerve injury, thereby contributing to neuropathic pain hypersensitivity. Interestingly, Slack is closely associated with ATP-sensitive P2X3 receptors in a population of sensory neurons. In vitro experiments revealed that Slack-mediated IKNa may be bidirectionally modulated in response to P2X3 activation. Moreover, mice lacking Slack show altered nocifensive responses to P2X3 stimulation. Our study identifies P2X3/Slack signaling as a mechanism contributing to hypersensitivity after peripheral nerve injury and proposes a potential novel strategy for treatment of neuropathic pain.


Asunto(s)
Adenosina Trifosfato/análogos & derivados , Calcio/farmacología , Proteínas del Tejido Nervioso/metabolismo , Neuralgia/metabolismo , Canales de potasio activados por Sodio/metabolismo , Receptores Purinérgicos P2X3/metabolismo , Células Receptoras Sensoriales/fisiología , Adenosina Trifosfato/farmacología , Animales , Escala de Evaluación de la Conducta , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas del Tejido Nervioso/genética , Técnicas de Placa-Clamp , Nervios Periféricos/patología , Canales de Potasio/metabolismo , Canales de Potasio/fisiología , Canales de potasio activados por Sodio/genética , Receptores Purinérgicos P2X3/fisiología , Células Receptoras Sensoriales/efectos de los fármacos , Células Receptoras Sensoriales/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Transducción de Señal/fisiología
14.
Nat Mater ; 18(7): 760-769, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30911119

RESUMEN

Integrins are membrane receptors that mediate cell adhesion and mechanosensing. The structure-function relationship of integrins remains incompletely understood, despite the extensive studies carried out because of its importance to basic cell biology and translational medicine. Using a fluorescence dual biomembrane force probe, microfluidics and cone-and-plate rheometry, we applied precisely controlled mechanical stimulations to platelets and identified an intermediate state of integrin αIIbß3 that is characterized by an ectodomain conformation, ligand affinity and bond lifetimes that are all intermediate between the well-known inactive and active states. This intermediate state is induced by ligand engagement of glycoprotein (GP) Ibα via a mechanosignalling pathway and potentiates the outside-in mechanosignalling of αIIbß3 for further transition to the active state during integrin mechanical affinity maturation. Our work reveals distinct αIIbß3 state transitions in response to biomechanical and biochemical stimuli, and identifies a role for the αIIbß3 intermediate state in promoting biomechanical platelet aggregation.


Asunto(s)
Fenómenos Mecánicos , Agregación Plaquetaria , Complejo GPIIb-IIIa de Glicoproteína Plaquetaria/metabolismo , Fenómenos Biomecánicos , Humanos , Ligandos , Transducción de Señal
15.
Chemistry ; 26(19): 4246-4250, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32012367

RESUMEN

The radical-radical coupling reaction is an important synthetic strategy. In this study, the iron-catalyzed radical-radical cross-coupling reaction based on the decarboxylation of keto acids and decarbonylation of aliphatic aldehydes to obtain valuable aryl ketones is reported for the first time. Remarkably, when tertiary aldehydes were used as carbonyl sources, ketone esters were selectively obtained instead of ketones. The gram-scale preparation of aryl ketone through this strategy was easily achieved by using only 3 mol % of the iron catalyst. As a proof-of-concept, the bioactive molecule flurprimidol was synthesized in two steps by using this strategy.

16.
Fish Shellfish Immunol ; 102: 350-360, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32371258

RESUMEN

Succinate dehydrogenase (SDH) is a mitochondrial enzyme with the unique ability to participate in both the tricarboxylic acid cycle and the electron transport chain to produce reactive oxygen species (ROS). The B subunit of SDH is required for succinate oxidation, which is critical for pro-inflammatory response. In this study, we cloned the iron-sulfur protein subunit of SDH from Apostichopus japonicus (denoted as AjSDHB) via RACE technology and explored its role in the immune system as a response to pathogen infection. The full-length cDNA of AjSDHB was 1442 bp with a complete open reading frame of 858 bp encoding 286 amino acids. Simple modular architecture research tool analysis revealed that AjSDHB contained two conserved domains, including a 2Fe-2S iron-sulfur cluster binding domain and a 4Fe-4S dicluster domain, without a signal peptide. Multiple sequence alignment demonstrated that AjSDHB shared a high degree of structural conservation and sequence identities with other counterparts from invertebrates and vertebrates. Phylogenetic analysis supported the finding that AjSDHB is a new member of the SDHB protein subfamily. Tissue distribution analysis revealed that AjSDHB was expressed in all examined tissues and particularly highly expressed in the muscles. AjSDHB transcripts were markedly induced in coelomocytes both by Vibrio splendidus challenge in vivo and lipopolysaccharide exposure in vitro. Function analysis showed that siRNA-mediated AjSDHB knockdown could substantially reduce the mitochondrial membrane potential (ΔΨm) and further decrease mitochondrial ROS production in A. japonicus coelomocytes. By contrast, AjSDHB overexpression considerably increased ΔΨm and mitochondrial ROS production of A. japonicus coelomocytes. These results supported the idea that AjSDHB is involved in the innate immunity of A. japonicus through its participation in mitochondrial ROS generation.


Asunto(s)
Proteínas Hierro-Azufre/genética , Especies Reactivas de Oxígeno/metabolismo , Stichopus/genética , Stichopus/inmunología , Stichopus/metabolismo , Succinato Deshidrogenasa/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas Hierro-Azufre/metabolismo , Lipopolisacáridos/farmacología , Mitocondrias/metabolismo , Filogenia , Alineación de Secuencia , Stichopus/enzimología , Succinato Deshidrogenasa/genética , Vibrio/fisiología
17.
Mol Pain ; 14: 1744806918796057, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30152258

RESUMEN

Extracellular regulated protein kinase (ERK) pathway activation in astrocytes and neurons has been reported to be critical for neuropathic pain development after chronic constriction injury. TGN-020 was found to be the most potent aquaporin 4 inhibitor among the agents studied. The present study aimed to assess whether the inhibition of aquaporin 4 had an analgesic effect on neuropathic pain and whether the inhibition of astrocytic activation and ERK pathway was involved in the analgesic effect of TGN-020. We thus found that TGN-020 upregulated the threshold of thermal and mechanical allodynia, downregulated the expression of interleukin-1ß, interleukin-6, and tumor necrosis factor-α, attenuated the astrocytic activation and suppressed the activation of mitogen-activated protein kinase pathways in the spinal dorsal horn and dorsal root ganglion. Additionally, TGN-020 suppressed ERK phosphorylation in astrocytes and neurons after injury. The findings suggested that the analgesic effects of TGN-020 in neuropathic pain were mediated mainly by the downregulation of chronic constriction injury-induced astrocytic activation and inflammation, which is via the inhibition of ERK pathway in the spinal dorsal horn and dorsal root ganglion.


Asunto(s)
Analgésicos/uso terapéutico , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Neuralgia/tratamiento farmacológico , Niacinamida/análogos & derivados , Tiadiazoles/uso terapéutico , Animales , Acuaporina 4/antagonistas & inhibidores , Acuaporina 4/metabolismo , Modelos Animales de Enfermedad , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/etiología , Masculino , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Niacinamida/uso terapéutico , Umbral del Dolor/efectos de los fármacos , Fosfopiruvato Hidratasa/metabolismo , Ratas , Ratas Sprague-Dawley , Regulación hacia Arriba/efectos de los fármacos
18.
Horm Metab Res ; 50(1): 65-72, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29329467

RESUMEN

Several groups have reported the important role of estradiol (E2) and testosterone (T) in postmenopausal osteoporosis (PMOP). Because aromatase catalyzes the conversion of T to E2, the purpose of this study was to determine the influence of aromatase activity on the bone mineral density (BMD) in postmenopausal women. A total of 344 postmenopausal women were selected for this study. Serum E2, T, sex hormone-binding globulin (SHBG), calcium (Ca), alkaline phosphatase (ALP), C-terminal telopeptide of type I collagen (CTX), and procollagen type I amino-terminal propeptide (PINP) were examined. The E2/T was positively associated with total hip BMD and PINP (p<0.05). When E2/T was divided into quartiles, participants in lower quartiles of E2/T were likely to have higher PINP and lower BMD (p<0.05). The prevalence of osteoporosis significantly increased as E2/T ratio decreased. The receiver operating characteristic (ROC) curves were constructed for serum E2, free E2 index (FEI), and E2/T, to assess their diagnostic accuracy in PMOP. The overall area under the curve (AUC) were 0.83 (95% CI=0.77-0.88) for E2, 0.87 (95% CI=0.82-0.92) for FEI, and 0.89 (95% CI=0.85-0.94), respectively. In conclusion, the study suggests that in postmenopausal women, aromatase activity could be an important determinant of skeletal health. The women with lower aromatase activity may have greater likelihood of PMOP and the E2/T was expected to be a valuable indicator for the prediction of PMOP and to monitor the process of osteoporosis.


Asunto(s)
Aromatasa/metabolismo , Pueblo Asiatico , Densidad Ósea , Estradiol/metabolismo , Cadera/fisiopatología , Osteoporosis Posmenopáusica/metabolismo , Osteoporosis Posmenopáusica/fisiopatología , Globulina de Unión a Hormona Sexual/metabolismo , Anciano , Biomarcadores/metabolismo , Enfermedades Óseas Metabólicas/epidemiología , Remodelación Ósea , Femenino , Humanos , Funciones de Verosimilitud , Modelos Lineales , Persona de Mediana Edad , Osteoporosis Posmenopáusica/epidemiología , Posmenopausia , Prevalencia , Curva ROC
19.
Nano Lett ; 17(9): 5429-5436, 2017 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-28753017

RESUMEN

The success of cancer chemotherapy is impeded by poor drug delivery efficiency due to the existence of a series of pathophysiological barriers in the tumor. In this study, we reported a tumor acidity-triggered ligand-presenting (ATLP) nanoparticle for cancer therapy. The ATLP nanoparticles were composed of an acid-responsive diblock copolymer as a sheddable matrix and an iRGD-modified polymeric prodrug of doxorubicin (iPDOX) as an amphiphilic core. A PEG corona of the polymer matrix protected the iRGD ligand from serum degradation and nonspecific interactions with the normal tissues while circulating in the blood. The ATLP nanoparticles specifically accumulated at the tumor site through the enhanced permeability and retention (EPR) effect, followed by acid-triggered dissociation of the polymer matrix within the tumoral acidic microenvironment (pH ∼ 6.8) and subsequently exposing the iRGD ligand for facilitating tumor penetration and cellular uptake of the PDOX prodrug. Additionally, the acid-triggered dissociation of the polymer matrix induced a 4.5-fold increase of the fluorescent signal for monitoring nanoparticle activation in vivo. Upon near-infrared (NIR) laser irradiation, activation of Ce6-induced significant reactive oxygen species (ROS) generation, promoted drug diffusion inside the tumor mass and circumvented the acquired drug resistance by altering the gene expression profile of the tumor cells. The ATLP strategy might provide a novel insight for cancer nanomedicine.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Preparaciones de Acción Retardada/química , Doxorrubicina/administración & dosificación , Nanopartículas/química , Ácidos/química , Animales , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/uso terapéutico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Doxorrubicina/farmacocinética , Doxorrubicina/uso terapéutico , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Concentración de Iones de Hidrógeno , Ligandos , Células MCF-7 , Ratones Desnudos , Microambiente Tumoral/efectos de los fármacos
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