RESUMO
Initiation and progression of leaf senescence are triggered by various environmental stressors and phytohormones. Jasmonic acid (JA) and darkness accelerate leaf senescence in plants. However, the mechanisms that integrate these two factors to initiate and regulate leaf senescence have not been identified. Here, we report a transcriptional regulatory module centred on a novel tomato WRKY transcription factor, SlWRKY37, responsible for both JA- and dark-induced leaf senescence. The expression of SlWRKY37, together with SlMYC2, encoding a master transcription factor in JA signalling, was significantly induced by both methyl jasmonate (MeJA) and dark treatments. SlMYC2 binds directly to the promoter of SlWRKY37 to activate its expression. Knock out of SlWRKY37 inhibited JA- and dark-induced leaf senescence. Transcriptome analysis and biochemical experiments revealed SlWRKY53 and SlSGR1 (S. lycopersicum senescence-inducible chloroplast stay-green protein 1) as direct transcriptional targets of SlWRKY37 to control leaf senescence. Moreover, SlWRKY37 interacted with a VQ motif-containing protein SlVQ7, and the interaction improved the stability of SlWRKY37 and the transcriptional activation of downstream target genes. Our results reveal the physiological and molecular functions of SlWRKY37 in leaf senescence, and offer a target gene to retard leaf yellowing by reducing sensitivity to external senescence signals, such as JA and darkness.
Assuntos
Solanum lycopersicum , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Senescência Vegetal , Regulação da Expressão Gênica de Plantas , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Folhas de Planta/metabolismoRESUMO
Phytomelatonin is a small multifunctional molecule found ubiquitously in plants, which plays an important role in plant growth, development, and biotic and abiotic stress responses. The classical biosynthetic and metabolic pathways of phytomelatonin have been elucidated, and uncovering alternative pathways has deepened our understanding of phytomelatonin synthesis. Phytomelatonin functions mainly via two pathways. In the direct pathway, phytomelatonin mediates the stress-induced reactive oxygen species burst through its strong antioxidant capacity. In the indirect pathway, phytomelatonin acts as a signal to activate signaling cascades and crosstalk with other plant hormones. The phytomelatonin receptor PMTR1/CAND2 was discovered in 2018, which enhanced our understanding of phytomelatonin function. This review summarizes the classical and potential pathways involved in phytomelatonin synthesis and metabolism. To elucidate the functions of phytomelatonin, we focus on the crosstalk between phytomelatonin and other phytohormones. We propose two models to explain how PMTR1 transmits the phytomelatonin signal through the G protein and MAPK cascade. This review will facilitate the identification of additional signaling molecules that function downstream of the phytomelatonin signaling pathway, thus improving our understanding of phytomelatonin signal transmission.
Assuntos
Melatonina , Reguladores de Crescimento de Plantas , Antioxidantes , Melatonina/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Estresse FisiológicoRESUMO
Jasmonic acid (JA) is a key regulator of plant defense responses. Although the transcription factor MYC2, the master regulator of the JA signaling pathway, orchestrates a hierarchical transcriptional cascade that regulates the JA responses, only a few transcriptional regulators involved in this cascade have been described. Here, we identified the basic helix-loop-helix (bHLH) transcription factor gene in tomato (Solanum lycopersicum), METHYL JASMONATE (MeJA)-INDUCED GENE (SlJIG), the expression of which was strongly induced by MeJA treatment. Genetic and molecular biology experiments revealed that SlJIG is a direct target of MYC2. SlJIG knockout plants generated by gene editing had lower terpene contents than the wild type from the lower expression of TERPENE SYNTHASE (TPS) genes, rendering them more appealing to cotton bollworm (Helicoverpa armigera). Moreover, SlJIG knockouts exhibited weaker JA-mediated induction of TPSs, suggesting that SlJIG may participate in JA-induced terpene biosynthesis. Knocking out SlJIG also resulted in attenuated expression of JA-responsive defense genes, which may contribute to the observed lower resistance to cotton bollworm and to the fungus Botrytis cinerea. We conclude that SlJIG is a direct target of MYC2, forms a MYC2-SlJIG module, and functions in terpene biosynthesis and resistance against cotton bollworm and B. cinerea.
Assuntos
Proteínas de Arabidopsis , Solanum lycopersicum , Animais , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ciclopentanos/metabolismo , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas , Insetos , Solanum lycopersicum/genética , Solanum lycopersicum/metabolismo , Oxilipinas/metabolismo , Oxilipinas/farmacologia , TerpenosRESUMO
Pentatricopeptide repeat (PPR) proteins play important roles in the post-transcriptional modification of organellar RNAs in plants. However, the function of most PPR proteins remains unknown. Here, we characterized the rice (Oryza sativa L.) chlorophyll deficient 4 (cde4) mutant which exhibits an albino phenotype during early leaf development, with decreased chlorophyll contents and abnormal chloroplasts at low-temperature (20°C). Positional cloning revealed that CDE4 encodes a P-type PPR protein localized in chloroplasts. In the cde4 mutant, plastid-encoded polymerase (PEP)-dependent transcript levels were significantly reduced, but transcript levels of nuclear-encoded genes were increased compared to wild-type plants at 20°C. CDE4 directly binds to the transcripts of the chloroplast genes rpl2, ndhA, and ndhB. Intron splicing of these transcripts was defective in the cde4 mutant at 20°C, but was normal at 32°C. Moreover, CDE4 interacts with the guanylate kinase VIRESCENT 2 (V2); overexpression of V2 enhanced CDE4 protein stability, thereby rescuing the cde4 phenotype at 20°C. Our results suggest that CDE4 participates in plastid RNA splicing and plays an important role in rice chloroplast development under low-temperature conditions.
Assuntos
Cloroplastos/fisiologia , Oryza/genética , Proteínas de Plantas/genética , Splicing de RNA , RNA de Cloroplastos/metabolismo , Proteínas de Arabidopsis , Clorofila/metabolismo , Guanilato Quinases/metabolismo , Oryza/metabolismo , Desenvolvimento Vegetal , Proteínas de Plantas/metabolismo , TemperaturaRESUMO
The SNAT enzyme participates in the biosynthesis of melatonin, which is reported to regulate thermotolerance in many plants. However, the mechanistic basis of this regulation remains unclear. In this study, we identified the SlSNAT gene, which is responsible for melatonin biosynthesis in tomato. SlSNAT expression levels were 3- and 5-fold higher in SlSNAT overexpression lines OX-2 and OX-6, respectively. The melatonin levels were 3- and 4-fold higher than those in wild type. The melatonin levels decreased by 50% when the expression of SlSNAT was downregulated to 40%. Overexpression of SlSNAT in tomato plants provided significantly enhanced thermotolerance with better growth performance in Photosystem II (PSII) maximum photochemical quantum yield (Fv/Fm) and alleviated heat injury. Both exogenous melatonin treatment and endogenous melatonin manipulation by SlSNAT overexpression decreased the levels of reactive oxygen species�accumulation and Fv/Fm. The SlSNAT overexpression line showed protected ribulose bisphosphate carboxylase oxygenase proteins and upregulated response of heat transcription factors and heat shock proteins under heat stress. HSP40, a DnaJ-type chaperone, was found to interact with SlSNAT in the chloroplast. Downregulation of HSP40 showed lower melatonin synthesis under heat stress. HSP40 functions as a chaperone to protect the SNAT enzyme during melatonin synthesis under heat stress. HSP40 interacted with SlSNAT and together participated in melatonin-related thermotolerance regulation in tomato.
Assuntos
Proteínas de Choque Térmico HSP40/metabolismo , Melatonina/biossíntese , Proteínas de Plantas/metabolismo , Solanum lycopersicum/fisiologia , Termotolerância/fisiologia , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico HSP40/genética , Resposta ao Choque Térmico/genética , Solanum lycopersicum/genética , Modelos Biológicos , Proteínas de Plantas/genética , Ligação Proteica , Espécies Reativas de Oxigênio/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Termotolerância/genéticaRESUMO
Improving plant water-use efficiency (WUE) is important to plant survival and crop yield in the context of water limitation. In this study, SlTLFP8 (Tubby-like F-box protein 8) was identified as an osmotic-induced gene in tomato. Transgenic tomato with up-regulated expression of SlTLFP8 showed enhanced water-deficient resistance, whereas knockout mutants generated by CRISPR/Cas9 were more sensitive to water deficit. SlTLFP8 overexpression significantly enhanced WUE by suppressing transpiration under both water-sufficient and water-deficient conditions. Further study showed that overexpressing SlTLFP8 significantly increased leaf epidermal cell size and thereby decreased stomatal density 10-20%, conversely SlTLFP8 knockout resulted in decreased cell size and thereby increased stomatal density 20-50%. SlTLFP8 overexpression and knockout modulated ploidy levels in leaf cells. Changes in expression of cell cycle related genes also indicated that SlTLFP8 affected cell size and stomatal density through endocycle transition. Despite changes in stomata density and transpiration, altering the expression of SlTLFP8 did not change photosynthesis. Additionally, biomass was not altered and there was little difference in fruit yield for transgenic and wild type lines under water-sufficient and water-deficient conditions. Our results demonstrate the effect of SlTLFP8 on endoreduplication and the potential of SlTLFP8 for improvement of WUE. BRIEF SUMMERY: This work found a new mechanism of TLP (Tubby like protein) response to water-deficient stress. SlTLFP8, a member of TLP family, regulates water-deficient resistance by modulating water loss via affecting stomatal density. Expression of SlTLFP8 was induced by osmotic stress. Transgenic tomato lines with SlTLFP8 overexpression or SlTLFP8 knockout showed significantly differences in water-use efficiency (WUE) and water-deficient resistance. The difference of leaf water loss caused by transpiration is the main explanation of the difference in WUE and water-deficient resistance. Additionally, overexpressing SlTLFP8 significantly decreased stomatal density, while SlTLFP8 knockout resulted in increased stomatal density, and SlTLFP8 affected stomatal density through endoreduplication and altered epidermal cell size. Despite changes in stomata density, altering the expression of SlTLFP8 did not result in distinct changes in photosynthesis, biomass and yield of tomato.
Assuntos
Endorreduplicação , Proteínas F-Box/fisiologia , Proteínas de Plantas/fisiologia , Estômatos de Plantas/anatomia & histologia , Transpiração Vegetal , Água/metabolismo , Proteína 9 Associada à CRISPR , Sistemas CRISPR-Cas , Tamanho Celular , Proteínas F-Box/metabolismo , Técnicas de Silenciamento de Genes , Solanum lycopersicum/genética , Solanum lycopersicum/fisiologia , Proteínas de Plantas/metabolismo , Estômatos de Plantas/fisiologia , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Nine new sesquiterpene quinones/hydroquinones (1-7, 10, and 12), three solvent-generated artifacts (8, 9, and 11), and three known compounds, 5-epi-smenospongine (13), smenospongine (14), and smenospongiadine (15), were isolated from the marine sponge Spongia pertusa Esper. The planar structures of the new compounds were elucidated on the basis of spectroscopic analyses. Their absolute configurations were determined by comparison between the calculated and experimental ECD spectra. In the cytotoxicity bioassay, compounds 13-15 exhibited activities against the human cancer cell lines U937, HeLa, and HepG2, with most potent cytotoxicities to U937 cells with IC50 values of 2.8, 1.5, and 0.6 µM, respectively. In addition, compound 6 displayed CDK-2 affinity with a Kd value of 4.8 µM in a surface plasmon resonance assay.
Assuntos
Células Hep G2/efeitos dos fármacos , Hidroquinonas/isolamento & purificação , Hidroquinonas/farmacologia , Poríferos/química , Quinonas/farmacologia , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Hidroquinonas/química , Concentração Inibidora 50 , Estrutura Molecular , Quinonas/química , Quinonas/isolamento & purificação , Sesquiterpenos/químicaRESUMO
BACKGROUND: Administration of onabotulinumtoxinA (BoNT-A) to peripheral tissues outside the calvaria reduces the number of days chronic migraine patients experience headache. Because the headache phase of a migraine attack, especially those preceded by aura, is thought to involve activation of meningeal nociceptors by endogenous stimuli such as changes in intracranial pressure (i.e. mechanical) or chemical irritants that appear in the meninges as a result of a yet-to-be-discovered sequence of molecular/cellular events triggered by the aura, we sought to determine whether extracranial injections of BoNT-A alter the chemosensitivity of meningeal nociceptors to stimulation of their intracranial receptive fields. MATERIAL AND METHODS: Using electrophysiological techniques, we identified 161 C- and 135 Aδ-meningeal nociceptors in rats and determined their mechanical response threshold and responsiveness to chemical stimulation of their dural receptive fields with TRPV1 and TRPA1 agonists seven days after BoNT-A administration to different extracranial sites. Two paradigms were compared: distribution of 5 U BoNT-A to the lambdoid and sagittal sutures alone, and 1.25 U to the sutures and 3.75 U to the temporalis and trapezius muscles. RESULTS: Seven days after it was administered to tissues outside the calvaria, BoNT-A inhibited responses of C-type meningeal nociceptors to stimulation of their intracranial dural receptive fields with the TRPV1 agonist capsaicin and the TRPA1 agonist mustard oil. BoNT-A inhibition of responses to capsaicin was more effective when the entire dose was injected along the suture lines than when it was injected into muscles and sutures. As in our previous study, BoNT-A had no effect on non-noxious mechanosensitivity of C-fibers or on responsiveness of Aδ-fibers to mechanical and chemical stimulation. DISCUSSION: This study demonstrates that extracranial administration of BoNT-A suppresses meningeal nociceptors' responses to stimulation of their intracranial dural receptive fields with capsaicin and mustard oil. The findings suggest that surface expression of TRPV1 and TRPA1 channels in dural nerve endings of meningeal nociceptors is reduced seven days after extracranial administration of BoNT-A. In the context of chronic migraine, reduced sensitivity to molecules that activate meningeal nociceptors through the TRPV1 and TRPA1 channels can be important for BoNT-A's ability to act as a prophylactic.
Assuntos
Toxinas Botulínicas Tipo A/farmacologia , Meninges/efeitos dos fármacos , Transtornos de Enxaqueca/fisiopatologia , Fármacos Neuromusculares/farmacologia , Nociceptores/efeitos dos fármacos , Animais , Capsaicina/farmacologia , Suturas Cranianas/efeitos dos fármacos , Masculino , Músculo Esquelético/efeitos dos fármacos , Mostardeira , Óleos de Plantas/farmacologia , Ratos , Ratos Sprague-Dawley , Fármacos do Sistema Sensorial/farmacologia , Canal de Cátion TRPA1 , Canais de Cátion TRPC/agonistas , Canais de Cátion TRPV/agonistasRESUMO
OBJECTIVE: To examine changes in the response properties of meningeal nociceptors that might lead to migraine pain and examine endogenous processes that could play a role in mediating them using a clinically relevant model of migraine triggering, namely infusion of the nitric oxide (NO) donor nitroglycerin (NTG). METHODS: Single-unit recordings made in the trigeminal ganglion of rats were used to test changes in the activity and mechanosensitivity of meningeal nociceptors in response to administration of the migraine trigger NTG or another NO donor S-nitroso-N-acetyl-DL-penicillamine (SNAP) at doses relevant to the human model of migraine headache. Immunohistochemistry and pharmacological manipulations were used to investigate the possible role of meningeal vascular signaling in mediating the responses of meningeal nociceptors to NO. RESULTS: Infusion of NTG promoted a delayed and robust increase in the mechanosensitivity of meningeal nociceptors, with a time course resembling the development of the delayed migraine headache. A similar sensitization was elicited by dural application of NTG and SNAP. NTG-evoked delayed meningeal nociceptor sensitization was associated with a robust extracellular signal-regulated kinase (ERK) phosphorylation in meningeal arteries. Pharmacological blockade of meningeal ERK phosphorylation inhibited the development of NTG-evoked delayed meningeal nociceptor sensitization. INTERPRETATION: The development of delayed mechanical sensitization evoked by the migraine trigger NTG is potentially of great importance as the first finding of a neurophysiological correlate of migraine headache in meningeal nociceptors. The arterial ERK phosphorylation and its involvement in mediating the NTG-evoked delayed sensitization points to an important, yet unappreciated, role of the meningeal vasculature in the genesis of migraine pain.
Assuntos
MAP Quinases Reguladas por Sinal Extracelular/fisiologia , Meninges/irrigação sanguínea , Meninges/enzimologia , Transtornos de Enxaqueca/enzimologia , Nociceptores/enzimologia , Animais , Masculino , Meninges/efeitos dos fármacos , Transtornos de Enxaqueca/induzido quimicamente , Doadores de Óxido Nítrico/toxicidade , Nociceptores/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Gânglio Trigeminal/efeitos dos fármacos , Gânglio Trigeminal/enzimologiaRESUMO
BACKGROUND: Meningeal and other trigeminal nociceptors are thought to play important roles in the initiation of migraine headache. Currently, the only approved peripherally administered chronic migraine prophylactic drug is onabotulinumtoxinA. The purpose of this study was to determine how botulinum neurotoxin type A (BoNT-A) affects naïve and sensitized meningeal nociceptors. MATERIAL AND METHODS: Using electrophysiological techniques, we identified 43 C- and 36 Aδ-meningeal nociceptors, and measured their spontaneous and evoked firing before and after BoNT-A administration to intracranial dura and extracranial suture-receptive fields. RESULTS: As a rule, BoNT-A inhibited C- but not Aδ-meningeal nociceptors. When applied to nonsensitized C-units, BoNT-A inhibited responses to mechanical stimulation of the dura with suprathreshold forces. When applied to sensitized units, BoNT-A reversed mechanical hypersensitivity. When applied before sensitization, BoNT-A prevented development of mechanical hypersensitivity. When applied extracranially to suture branches of intracranial meningeal nociceptors, BoNT-A inhibited the mechanical responsiveness of the suture branch but not dural axon. In contrast, BoNT-A did not inhibit C-unit responses to mechanical stimulation of the dura with threshold forces, or their spontaneous activity. DISCUSSION: The study provides evidence for the ability of BoNT-A to inhibit mechanical nociception in peripheral trigeminovascular neurons. These findings suggest that BoNT-A interferes with neuronal surface expression of high-threshold mechanosensitive ion channels linked preferentially to mechanical pain by preventing their fusion into the nerve terminal membrane.
Assuntos
Toxinas Botulínicas Tipo A/farmacologia , Meninges/efeitos dos fármacos , Transtornos de Enxaqueca/fisiopatologia , Neurotoxinas/farmacologia , Nociceptores/efeitos dos fármacos , Animais , Eletrofisiologia , Masculino , Mecanotransdução Celular/fisiologia , Microeletrodos , Dor/fisiopatologia , Ratos , Ratos Sprague-DawleyRESUMO
We proposed recently that induction of delayed activation of trigeminovascular neurons by cortical spreading depression (CSD) can explain the delayed onset of headache after the migraine aura ("aura"). This prompted us to search for ways to block the neuronal activation by CSD - a preclinical correlate of an attempt to find a drug that can block the initiation of headache when administered shortly after onset of aura (i.e., preemptively). Because migraine headache and epileptic seizures are comorbid chronic neurological disorders characterized by hyperexcitable brain networks, we began the search for such goal with an M-type potassium channel opener. We opted to use ezogabine, recently approved by the FDA as adjunctive treatment of partial onset seizures in adults, because it is a selective KCNQ2/3 channel opener. When CSD was induced before ezogabine injection (8.25 mg/kg, i.p.), 40% (6/15) of the units doubled their firing rate about 45 min later for about 95 min. Similarly, when CSD was induced before vehicle was injected (4% DMSO, 0.5% methylcellulose), 50% (3/6) of the units doubled their firing rate about 30 min later for about 120 min. When CSD was triggered 1h after ezogabine injection, it activated only 8% of the units. By itself, ezogabine injection resulted in a 30% attenuation of ongoing firing in all 10 control units. Thus, activation of KCNQ2/3 channels during the aura is unlikely to preempt the onset of headache but may reduce the incidence of migraine if given during prodromes that precede the headache by hours. Given the mechanistic similarities between migraine aura and epileptic seizures, it may be worthwhile to determine whether preemptive administration of ezogabine can prevent oncoming seizures in patients whose warning signs precede their seizures by more than an hour.
Assuntos
Anticonvulsivantes/administração & dosagem , Carbamatos/administração & dosagem , Depressão Alastrante da Atividade Elétrica Cortical/efeitos dos fármacos , Nociceptores/efeitos dos fármacos , Fenilenodiaminas/administração & dosagem , Gânglio Trigeminal/citologia , Potenciais de Ação/efeitos dos fármacos , Animais , Depressão Alastrante da Atividade Elétrica Cortical/fisiologia , Esquema de Medicação , Masculino , Medição da Dor , Estimulação Física , Ratos , Ratos Sprague-Dawley , Estimulação Química , Fatores de TempoRESUMO
The development of efficient electrocatalysts for large-scale water electrolysis is crucial and challenging. Research efforts towards interface engineering and electronic structure modulation can be leveraged to enhance the electrochemical performance of the developed catalysts. In this work, a surface-engineered Co-Ni3N/NF heterostructure electrode was prepared based on Kirkendall effect for high-current water electrolysis. In the experiments, the textural feature and intrinsic activity of the Co-Ni3N/NF heterostructure were tuned through cobalt-doping and the creation of structural defects. As a result, the increased surface energy endowed Co-Ni3N/NF heterostructure with superhydrophilic and superaerophobic properties. Meanwhile, the contact area of the gas-liquid-solid three phases was optimized. With a large underwater bubble contact angle (CA) of 169°, the electrolyte solution can infiltrate the Co-Ni3N/NF electrode within 150 ms. Sequentially, the generated gas bubbles were able to detach at high frequency, which ensured the rapid mass exchange. The performance tests showed that the optimal Co-Ni3N/NF electrode sample reached current densities of 100 mA cm-2 and 500 mA cm-2 at the overpotentials of 98 mV and 123 mV, respectively. Benefiting from the reduction of hydrogen embrittlement, the HER performance of the prepared Co-Ni3N/NF electrode sample decreased slightly after 100 h durability test, but the overall structure remained well. Those results allowed us to conclude that the prepared Co-Ni3N/NF electrocatalyst holds the promises for large-scale water electrolysis in industries. More specifically, this work provided a new perspective that the efficiency of electrocatalysts for large-scale water electrolysis can be enhanced by constructing a heterostructure with good wettability and gas repellency.
RESUMO
Background: Asthmatic patients with comorbid bronchiectasis (ACB) show significantly severe condition with various inflammatory phenotypes; bronchiectasis is a heterogeneous disease caused by asthma and other multiple etiological factors. We aimed to investigate the inflammatory characteristics and their clinical significance in asthmatic patients according to the presence and onset time of bronchiectasis. Methods: This prospective cohort study recruited outpatients with stable asthma. All the enrolled patients were divided into the non-bronchiectasis group and the ACB group, and the ACB group was separated into the bronchiectasis-prior group and the asthma-prior group. Demographic and clinical data were collected, and peripheral blood and induced sputum eosinophil counts, sputum pathogens, the fraction of exhaled nitric oxide (FeNO), lung function, and chest high-resolution computed tomography were examined. Results: A total of 602 patients (mean age: 55.36±14.58 years) were included, of which 255 (42.4%) were males. Bronchiectasis was present in 268 (44.5%) patients, with 171 (28.41%) in the asthma-prior group and 97 (16.11%) in the bronchiectasis-prior group. For the asthma-prior group, the presence of bronchiectasis was positively correlated with age, presence of nasal polyps, severe asthma, ≥1 pneumonia in the last 12 months, ≥1 severe exacerbation of asthma in the last 12 months (SEA), peripheral blood eosinophil counts, and sputum eosinophil ratio; the extent and severity of bronchiectasis were positively correlated with ≥1 SEA and FeNO levels; and the bronchiectasis severity index (BSI) scores were positively correlated with ≥1 SEA and immunoglobulin E levels. For the bronchiectasis-prior group, bronchiectasis was positively correlated with previous pulmonary tuberculosis or pneumonia in childhood and ≥1 pneumonia in the last 12 months and negatively correlated with forced expiratory volume in one second (FEV1) % and the FeNO level. The extent and severity of bronchiectasis were positively correlated with ≥1 pneumonia in the last 12 months and negatively correlated with FEV1%. The BSI scores were positively correlated with the duration of bronchiectasis. Conclusions: The sequence of bronchiectasis onset may indicate distinct inflammatory characteristics and may be helpful in targeted therapy for patients with asthma.
RESUMO
OBJECTIVE: Cortical spreading depression (CSD) has long been implicated in migraine attacks that begin with visual aura. Having shown that a wave of CSD can trigger long-lasting activation of meningeal nociceptors--the first-order neurons of the trigeminovascular pathway thought to underlie migraine headache--we now report that CSD can activate central trigeminovascular neurons in the spinal trigeminal nucleus (C1-2). METHODS: Stimulation of the cortex with pinprick or KCl granule was used to induce CSD in anesthetized rats. Neuronal activity was monitored in C1-2 using single-unit recording. RESULTS: In 25 trigeminovascular neurons activated by CSD, mean firing rate (spikes/s) increased from 3.6 ± 1.2 before CSD (baseline) to 6.1 ± 1.8 after CSD (p < 0.0001) for a period >13 minutes. Neuronal activity returned to baseline level after 30.0 ± 3.1 minutes in 14 units, and remained elevated for 66.0 ± 8.3 (22-108) minutes through the entire recording period in the other 11 units. Neuronal activation began within 0.9 ± 0.4 (0-2.5) minutes after CSD in 7 neurons located in laminae I-II, or after a latency of 25.1 ± 4.0 (7-75) minutes in 9 neurons located in laminae I-II, and 9 neurons located in laminae III-V. In 27 trigeminovascular neurons not activated by CSD, mean firing rate was 2.0 ± 0.7 at baseline and 1.8 ± 0.7 after CSD. INTERPRETATION: We propose that CSD constitutes a nociceptive stimulus capable of activating peripheral and central trigeminovascular neurons that underlie the headache of migraine with aura.
Assuntos
Potenciais de Ação/fisiologia , Depressão Alastrante da Atividade Elétrica Cortical/fisiologia , Neurônios/fisiologia , Nervo Trigêmeo/fisiologia , Núcleo Espinal do Trigêmeo/citologia , Animais , Mapeamento Encefálico , Masculino , Neurônios/classificação , Nociceptores/fisiologia , Estimulação Física/métodos , Ratos , Ratos Sprague-Dawley , Estatísticas não Paramétricas , Estimulação QuímicaRESUMO
BACKGROUND: Peripheral nociceptive action of the proinflammatory cytokines IL-1ß and IL-6 has been implicated in the pathogenesis of numerous pain syndromes. An increase in the level of these cytokines in jugular venous blood has been reported during migraine attacks, suggesting their potential involvement in mediating the intracranial headache of migraine. METHODS: In this work we examined, using in vivo single-unit recording of meningeal nociceptors in the trigeminal ganglion of anesthetized rats, whether the peripheral actions of IL-1ß and IL-6 can promote the activation and sensitization of nociceptors that innervate the intracranial meninges, two neural processes that are believed to play a key role in promoting the intracranial throbbing pain of migraine. RESULTS: We found that meningeal application of IL-1ß leads to the activation and mechanical sensitization of about 70% and 45% of the nociceptors respectively. In contrast, IL-6 was a very poor modulator of meningeal nociceptors' response properties affecting overall only about 20% of the nociceptors. CONCLUSIONS: Our study provides for the first time in vivo electrophysiological evidence that meningeal action of IL-1ß can promote the activation and increased mechanosensitivity of intracranial meningeal nociceptors and that IL-6 generally lacks these properties. Future studies are required to examine the mechanism that plays a role in mediating the nociceptive effects of IL-1ß on meningeal nociceptors, which may serve as a target for migraine therapy.
Assuntos
Interleucina-1beta/imunologia , Interleucina-6/imunologia , Meninges/imunologia , Transtornos de Enxaqueca/imunologia , Nociceptores/imunologia , Anestesia , Animais , Inflamação/imunologia , Inflamação/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Mecanorreceptores/imunologia , Mecanorreceptores/metabolismo , Meninges/metabolismo , Transtornos de Enxaqueca/metabolismo , Nociceptores/metabolismo , Ratos , Ratos Sprague-Dawley , Gânglio Trigeminal/imunologia , Gânglio Trigeminal/metabolismoRESUMO
Huangqin Decoction (HQD), a traditional Chinese medicine formula from the Shang Han Lun written by Zhang Zhongjing, has been used in China for nearly two thousand years. According to the traditional Chinese medicine and previous literature, HQD has the effect of clearing heat, removing toxins, relieving diarrhea and pain. Therefore, HQD was used to prevent or cure many diseases, such as inflammation, diarrhea, malaria, and other acute or chronic gastrointestinal diseases. The effect of HQD, one-herb-absent HQD treatments and enrofloxacin (ENR) on the average daily gain (ADG), mortality rates, visceral index and toll-like receptors (TLRs), inflammatory factors and intestinal microflora in E. coli O78-inoculated chicks were investigated. HQD supplementation increased ADG and reduced the mortality rates caused by E. coli challenge, decreased the heart, liver, bursa of Fabricius (BF) and spleen index. HQD supplementation decreased the serum lysozyme (LZM), IL-1ß, TNF-α, IL-10, IL-6 level, down-regulated the mRNA expression of TLR4, -5 and -15 in the spleen by E. coli challenged chicks, and up-regulated the mRNA expression of TLR4, -5 and -15 in BF. At the phylum level, HQD supplementation reversed the increase of Operational Taxonomic Unit (OTUs), decreased the relative abundance of harmful bacteria Proteobacteria, increased the relative abundance of probiotic bacteria Bacteroidetes and Firmicutes. At the genus level, HQD decreased the relative abundance of harmful bacteria Escherichia-Shigella and Pseudomonas. It means that HQD treatment reversed the change of the gut microbiota structure. Compared with HQD, HQD-DZ and HQD-HQ increased the mortality rates. HQD-HQ decreased the ADG and liver index. HQD-GC decreased the spleen index. All herb-absent increased the serum IL-6, but only the HQD-HQ and HQD-SY increased the serum TNF-α. All herb-absent did not activate the TLRs signaling pathways in spleen and BF of chicks. The harmful bacteria Escherichia-Shigella were increased in HQD-HQ and HQD-DZ treatments. HQD-DZ treatment also increased the level of Proteobacteria. The results showed that dietary supplementation with HQD, by down-regulating the mRNA expression of TLR4, -5 and -15 in the spleen, further decreasing the serum LZM and IL-1ß, TNF-α, IL-10, IL-6 level, improves the immune function and reverses the change of fecal microbiome in chicks challenged with E. coli. In herb-absent supplementation, the results showed that SY and DZ play a key role in reducing the levels of inflammatory factors and keeping fecal microbiome balance respectively. More importantly, HQ is indispensable in HQD, not only play a key role in reducing the level of inflammatory factors, but also in keeping the balance of fecal microflora.
Assuntos
Microbioma Gastrointestinal , Scutellaria baicalensis , Animais , Galinhas/microbiologia , Diarreia , Enrofloxacina/farmacologia , Escherichia coli/fisiologia , Imunidade , Interleucina-10/farmacologia , Interleucina-6/farmacologia , Muramidase/farmacologia , RNA Mensageiro/farmacologia , Scutellaria baicalensis/química , Receptor 4 Toll-Like , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Tubby-like protein (TLP) plays an important role in plant growth and development. In this investigation, the characteristics of 11 members in the SlTLP family were studied. SlTLP genes were classified into two subgroups, and the members containing the F-box domain were renamed SlTLFPs. Subcellular localization indicated that most of the SlTLPs were localized in the nucleus. Expression pattern analysis revealed that eight genes (SlTLFP1, 3, 5, 7-10, and SlTLP11) showed differential expression across various tissues, while SlTLFP2, 4, and 6 were widely expressed in all the organs tested. Most SlTLP genes were induced by biotic and abiotic stress treatments such as Botrytis cinerea, temperature, MeJA, and ABA. TLP proteins in tomato have no transcriptional activation activity, and most members with an F-box domain could interact with SUPPRESSOR OF KINETOCHORE PROTEIN 1 (SlSkp1) or Cullin1 (Cul1) or both. Experiments on CRISPR edited SlTLFP8 showed that the N-terminal F-box domain was necessary for its function such as DNA ploidy and stomata size regulation. Our findings suggested that the F-box domain interacts with Skp1 and Cul1 to form the SCF complex, suggesting that SlTLFPs, at least SlTLFP8, function mainly through the F-box domain as an E3 ligase.
Assuntos
Proteínas F-Box , Solanum lycopersicum , DNA/metabolismo , Proteínas F-Box/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ubiquitina-Proteína Ligases/metabolismoRESUMO
Attacks of migraine with aura represent a phenomenon in which abnormal neuronal activity in the cortex produces sensory disturbances (aura) some 20-40 min before the onset of headache. The purpose of this study was to determine whether cortical spreading depression (CSD)--an event believed to underlie visual aura--can give rise to activation of nociceptors that innervate the meninges--an event believed to set off migraine headache. CSD was induced in anesthetized male rats by stimulation of the visual cortex with electrical pulses, pin prick, or KCl; single-unit activity of meningeal nociceptors was monitored in vivo in the rat before and after CSD. Regardless of the method of cortical stimulation, induction of CSD was recorded in 64 trials. In 31 of those trials, CSD induced a twofold increase in meningeal nociceptor firing rate that persisted for 37.0 +/- 4.6 min in trials in which activity returned to baseline, or >68 min in trials in which activity remained heightened at the time recording was interrupted. In two-thirds of the trials, onset of long-lasting neuronal activation began approximately 14 min after the wave of CSD. The findings demonstrates for the first time that induction of CSD by focal stimulation of the rat visual cortex can lead to long-lasting activation of nociceptors that innervate the meninges. We suggest that migraine with aura is initiated by waves of CSD that lead up to delayed activation of the trigeminovascular pathway.
Assuntos
Depressão Alastrante da Atividade Elétrica Cortical/fisiologia , Meninges/fisiologia , Nociceptores/fisiologia , Córtex Visual/fisiologia , Potenciais de Ação , Animais , Estimulação Elétrica , Masculino , Meninges/fisiopatologia , Enxaqueca com Aura/fisiopatologia , Neurotoxinas/toxicidade , Estimulação Física , Cloreto de Potássio/toxicidade , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Córtex Visual/efeitos dos fármacos , Córtex Visual/fisiopatologiaRESUMO
ãTwo Bacillus strains were screened and identified using 16S rRNA gene sequencing the phenotypic tests, and then characterized in vitro for the probiotic characteristics. They were able to tolerate pH 2.5 for 2.5 h, following 0.3% bile salts and 0.1% pancreatin treatment for 5 h. They exhibited good ability to attach to intestinal epithelial cells and were susceptible to most of the antibiotics and being killed by several. Further and more important, they showed good proteolytic activity to food protein as gelatin and milk, with even higher activity than the reference strain. Thus, these two Bacillus strains are considered as potential proteolytic probiotic strains to food proteins.
Assuntos
Bacillus , Probióticos , Antibacterianos , Bacillus/genética , Proteínas Alimentares , Fezes , RNA Ribossômico 16S/genéticaRESUMO
Herein, we identified the tomato SlMYB102 gene as a MYB family transcription factor of the R2R3-MYB subfamily. We additionally determined that the SlMYB102 promoter region contains photoresponsive, abiotic stress-responsive, and hormone-responsive regulatory elements, and we detected higher SlMYB102 expression in the reproductive organs of tomato than that in vegetative organs, with the expression being highest in ripe fruits and in roots. SlMYB102 expression was also shown to be cold-inducible. The protein encoded by SlMYB102 localized to the nucleus wherein it was found to mediate the transcriptional activation of target genes through its C-terminal domain. Overexpression of SlMYB102 in tomato plants conferred enhanced tolerance to cold stress. Under such cold stress conditions, we found that proline levels in the leaves of SlMYB102 overexpressing transgenic plants were higher than those in WT plants. In addition, S1MYB102 overexpression was associated with the enhanced expression of cold response genes including SlCBF1, SlCBF3, SlDREB1, SlDEB2, and SlICE1. We also found that the overexpression of SlMYB102 further enhanced the cold-induced upregulation of SlP5CS and SlAPX2. Taken together, these results suggest that SlMYB102 may be involved in the C-repeat binding transcription factor (CBF) and proline synthesis pathways, thereby improving tomato plant cold resistance.