Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 573
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Plant Mol Biol ; 114(1): 6, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38265739

RESUMO

tRNA-derived small RNAs (tsRNAs), a new category of regulatory small non-coding RNA existing in almost all branches of life, have recently attracted broad attention. Increasing evidence has shown that tsRNAs are not random degradation debris of tRNAs, but products cleaved by specific endoribonucleases, with versatile functions in response to various developmental and environmental cues. However, it is still unclear about the diversity, biogenesis and function of tsRNAs in plants. In this study, we comprehensively profiled 10-60 nts small RNAs in Arabidopsis thaliana leaf with or without wounding stress and identified four 16 nts tiny tRFs (tRNA-derived fragments) sharply increased after wounding, namely tRF5'Ala. Notably, genetic, biochemical and bioinformatic data indicated that RNS2, a member of class II RNase T2 enzymes, was the main endoribonuclease responsible for the biogenesis of tRF5'Ala. Moreover, tRF5'Ala was highly abundant and conserved in Arabidopsis and rice pollen. However, tRF5'Ala did not associate with AGO 1 in vivo or display any inhibitory effect on the translation of a luciferase mRNA in vitro. Altogether, our study highlights the discovery of a novel class of tiny tsRNAs drastically increased under wounding stress as well as their generation by RNS2, which provides a new insight into tsRNAs research in plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ribonucleases , Biologia Computacional , RNA , RNA de Transferência , Proteínas de Arabidopsis/genética , Ribonucleases/genética
2.
Epilepsia ; 65(5): 1360-1373, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38517356

RESUMO

OBJECTIVES: Responsive neurostimulation (RNS) is an established therapy for drug-resistant epilepsy that delivers direct electrical brain stimulation in response to detected epileptiform activity. However, despite an overall reduction in seizure frequency, clinical outcomes are variable, and few patients become seizure-free. The aim of this retrospective study was to evaluate aperiodic electrophysiological activity, associated with excitation/inhibition balance, as a novel electrographic biomarker of seizure reduction to aid early prognostication of the clinical response to RNS. METHODS: We identified patients with intractable mesial temporal lobe epilepsy who were implanted with the RNS System between 2015 and 2021 at the University of Utah. We parameterized the neural power spectra from intracranial RNS System recordings during the first 3 months following implantation into aperiodic and periodic components. We then correlated circadian changes in aperiodic and periodic parameters of baseline neural recordings with seizure reduction at the most recent follow-up. RESULTS: Seizure reduction was correlated significantly with a patient's average change in the day/night aperiodic exponent (r = .50, p = .016, n = 23 patients) and oscillatory alpha power (r = .45, p = .042, n = 23 patients) across patients for baseline neural recordings. The aperiodic exponent reached its maximum during nighttime hours (12 a.m. to 6 a.m.) for most responders (i.e., patients with at least a 50% reduction in seizures). SIGNIFICANCE: These findings suggest that circadian modulation of baseline broadband activity is a biomarker of response to RNS early during therapy. This marker has the potential to identify patients who are likely to respond to mesial temporal RNS. Furthermore, we propose that less day/night modulation of the aperiodic exponent may be related to dysfunction in excitation/inhibition balance and its interconnected role in epilepsy, sleep, and memory.


Assuntos
Ritmo Circadiano , Epilepsia Resistente a Medicamentos , Epilepsia do Lobo Temporal , Humanos , Epilepsia do Lobo Temporal/terapia , Epilepsia do Lobo Temporal/fisiopatologia , Masculino , Feminino , Adulto , Ritmo Circadiano/fisiologia , Estudos Retrospectivos , Pessoa de Meia-Idade , Epilepsia Resistente a Medicamentos/terapia , Epilepsia Resistente a Medicamentos/fisiopatologia , Convulsões/fisiopatologia , Convulsões/terapia , Estimulação Encefálica Profunda/métodos , Resultado do Tratamento , Adulto Jovem , Eletroencefalografia/métodos
3.
Epilepsia ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052021

RESUMO

OBJECTIVE: Although >30% of epilepsy patients have drug-resistant epilepsy (DRE), typically those with generalized or multifocal disease have not traditionally been considered surgical candidates. Responsive neurostimulation (RNS) of the centromedian (CM) region of the thalamus now appears to be a promising therapeutic option for this patient population. We present outcomes following CM RNS for 13 patients with idiopathic generalized epilepsy (IGE) and eight with multifocal onsets that rapidly generalize to bilateral tonic-clonic (focal to bilateral tonic-clonic [FBTC]) seizures. METHODS: A retrospective review of all patients undergoing bilateral CM RNS by the senior author through July 2022 were reviewed. Electrodes were localized and volumes of tissue activation were modeled in Lead-DBS. Changes in patient seizure frequency were extracted from electronic medical records. RESULTS: Twenty-one patients with DRE underwent bilateral CM RNS implantation. For 17 patients with at least 1 year of postimplantation follow-up, average seizure reduction from preoperative baseline was 82.6% (SD = 19.0%, median = 91.7%), with 18% of patients Engel class 1, 29% Engel class 2, 53% Engel class 3, and 0% Engel class 4. There was a trend for average seizure reduction to be greater for patients with nonlesional FBTC seizures than for other patients. For patients achieving at least Engel class 3 outcome, median time to worthwhile seizure reduction was 203.5 days (interquartile range = 110.5-343.75 days). Patients with IGE with myoclonic seizures had a significantly shorter time to worthwhile seizure reduction than other patients. The surgical targeting strategy evolved after the first four subjects to achieve greater anatomic accuracy. SIGNIFICANCE: Patients with both primary and rapidly generalized epilepsy who underwent CM RNS experienced substantial seizure relief. Subsets of these patient populations may particularly benefit from CM RNS. The refinement of lead targeting, tuning of RNS system parameters, and patient selection are ongoing areas of investigation.

4.
Wound Repair Regen ; 32(4): 407-418, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38602090

RESUMO

An argon-based low-temperature plasma jet (LTPJ) was used to treat chronically infected wounds in Staphylococcus aureus-laden mice. Based on physicochemical property analysis and in vitro antibacterial experiments, the effects of plasma parameters on the reactive nitrogen and oxygen species (RNOS) content and antibacterial capacity were determined, and the optimal treatment parameters were determined to be 4 standard litre per minute and 35 W. Additionally, the plasma-treated activation solution had a bactericidal effect. Although RNOS are related to the antimicrobial effect of plasma, excess RNOS may be detrimental to wound remodelling. In vivo studies demonstrated that medium-dose LTPJ promoted MMP-9 expression and inhibited bacterial growth during the early stages of healing. Moreover, LTPJ increased collagen deposition, reduced inflammation, and restored blood vessel density and TGF-ß levels to normal in the later stages of wound healing. Therefore, when treating chronically infected wounds with LTPJ, selecting the medium dose of plasma is more advantageous for wound recovery. Overall, our study demonstrated that low-temperature plasma jets may be a potential tool for the treatment of chronically infected wounds.


Assuntos
Gases em Plasma , Staphylococcus aureus , Cicatrização , Infecção dos Ferimentos , Animais , Cicatrização/efeitos dos fármacos , Camundongos , Gases em Plasma/farmacologia , Infecção dos Ferimentos/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Modelos Animais de Doenças , Infecções Estafilocócicas , Masculino , Espécies Reativas de Nitrogênio/metabolismo
5.
J Pineal Res ; 76(1): e12937, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38241678

RESUMO

Seed germination (SG) is the first stage in a plant's life and has an immense importance in sustaining crop production. Abiotic stresses reduce SG by increasing the deterioration of seed quality, and reducing germination potential, and seed vigor. Thus, to achieve a sustainable level of crop yield, it is important to improve SG under abiotic stress conditions. Melatonin (MEL) is an important biomolecule that interplays in developmental processes and regulates many adaptive responses in plants, especially under abiotic stresses. Thus, this review specifically summarizes and discusses the mechanistic basis of MEL-mediated SG under abiotic stresses. MEL regulates SG by regulating some stress-specific responses and some common responses. For instance, MEL induced stress specific responses include the regulation of ionic homeostasis, and hydrolysis of storage proteins under salinity stress, regulation of C-repeat binding factors signaling under cold stress, starch metabolism under high temperature and heavy metal stress, and activation of aquaporins and accumulation of osmolytes under drought stress. On other hand, MEL mediated regulation of gibberellins biosynthesis and abscisic acid catabolism, redox homeostasis, and Ca2+ signaling are amongst the common responses. Nonetheless factors such as endogenous MEL contents, plant species, and growth conditions also influence above-mentioned responses. In conclusion, MEL regulates SG under abiotic stress conditions by interacting with different physiological mechanisms.


Assuntos
Germinação , Melatonina , Germinação/fisiologia , Melatonina/farmacologia , Sementes , Estresse Fisiológico , Plantas/metabolismo , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Environ Sci Technol ; 58(36): 16087-16099, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39205652

RESUMO

This study aims to fine-tune the plasma composition with a particular emphasis on reactive nitrogen species (RNS) including nitrogen dioxide (NO2), dinitrogen pentoxide (N2O5), and nitrous oxide (N2O), produced by a self-constructed cylindrical dielectric barrier discharge (CDBD). We demonstrated the effective manipulation of the plasma chemical profile by optimizing electrical properties, including the applied voltage and frequency, and by adjusting the nitrogen and oxygen ratios in the gas mixture. Additionally, quantification of these active species was achieved using Fourier transform infrared spectroscopy. The study further extends to exploring the aerosol polymerization of acrylamide (AM) into polyacrylamide (PAM), serving as a model reaction to evaluate the reactivity of different plasma-generated species, highlighting the significant role of NO2 in achieving high polymerization yields. Complementing our experimental data, molecular dynamics (MD) simulations, based on the ReaxFF reactive force field potential, explored the interactions between reactive oxygen species, specifically hydroxyl radicals (OH) and hydrogen peroxide (H2O2), with water molecules. Understanding these interactions, combined with the optimization of plasma chemistry, is crucial for enhancing the effectiveness of DBD plasma in environmental applications like air purification and water treatment.


Assuntos
Simulação de Dinâmica Molecular , Óxido Nitroso , Espécies Reativas de Nitrogênio , Espécies Reativas de Nitrogênio/química , Óxido Nitroso/química , Gases em Plasma/química , Dióxido de Nitrogênio/química , Peróxido de Hidrogênio/química
7.
Plant Cell Rep ; 43(11): 263, 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39412663

RESUMO

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are critical for plant development as well as for its stress response. They can function as signaling molecules to orchestrate a well-defined response of plants to biotic stress. These responses are further fine-tuned by phytohormones, such as salicylic acid, jasmonic acid, and ethylene, to modulate immune response. In the past decades, the intricacies of redox and phytohormonal signaling have been uncovered during plant-pathogen interactions. This review explores the dynamic interplay of these components, elucidating their roles in perceiving biotic threats and shaping the plant's defense strategy. Molecular regulators and sites of oxidative burst have been explored during pathogen perception. Further, the interplay between various components of redox and phytohormonal signaling has been explored during bacterial, fungal, viral, and nematode infections as well as during insect pest infestation. Understanding these interactions highlights gaps in the current knowledge and provides insights into engineering crop varieties with enhanced resistance to pathogens and pests. This review also highlights potential applications of manipulating regulators of redox signaling to bolster plant immunity and ensure global food security. Future research should explore regulators of these signaling pathways as potential target to develop biotic stress-tolerant crops. Further insights are also needed into roles of endophytes and host microbiome modulating host ROS and RNS pool for exploiting them as biocontrol agents imparting resistance against pathogens in plants.


Assuntos
Reguladores de Crescimento de Plantas , Plantas , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Estresse Fisiológico , Espécies Reativas de Oxigênio/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Plantas/metabolismo , Plantas/parasitologia , Plantas/microbiologia , Plantas/imunologia , Imunidade Vegetal , Transdução de Sinais , Doenças das Plantas/microbiologia , Doenças das Plantas/parasitologia , Doenças das Plantas/imunologia , Interações Hospedeiro-Patógeno , Oxirredução
8.
Plant Cell Rep ; 43(8): 198, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39023775

RESUMO

KEY MESSAGE: Plants respond to environmental challenges by producing reactive species such as ROS and RNS, which play critical roles in signaling pathways that lead to adaptation and survival strategies. Understanding these pathways, as well as their detection methods and effects on plant development and metabolism, provides insight into increasing crop tolerance to combined stresses. Plants encounter various environmental stresses (abiotic and biotic) that affect plant growth and development. Plants sense biotic and abiotic stresses by producing different molecules, including reactive species, that act as signaling molecules and stimulate secondary messengers and subsequent gene transcription. Reactive oxygen and nitrogen species (ROS and RNS) are produced in both physiological and pathological conditions in the plasma membranes, chloroplasts, mitochondria, and endoplasmic reticulum. Various techniques, including spectroscopy, chromatography, and fluorescence methods, are used to detect highly reactive, short-half-life ROS and RNS either directly or indirectly. In this review, we highlight the roles of ROS and RNS in seed germination, root development, senescence, mineral nutrition, and post-harvest control. In addition, we provide information on the specialized metabolism involved in plant growth and development. Secondary metabolites, including alkaloids, flavonoids, and terpenoids, are produced in low concentrations in plants for signaling and metabolism. Strategies for improving crop performance under combined drought and pathogen stress conditions are discussed in this review.


Assuntos
Plantas , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Transdução de Sinais , Estresse Fisiológico , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Plantas/metabolismo , Fenômenos Fisiológicos Vegetais , Desenvolvimento Vegetal
9.
Plant Cell Rep ; 43(10): 236, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39313563

RESUMO

KEY MESSAGE: AOX gene family in motion marks in-born efficiency of respiration adjustment; can serve for primer screening, genotype ranking, in vitro-plant discrimination and a SMART perspective for multiple-resilient plant holobiont selection. The bacteria Xylella fastidiosa (Xf) is a climate-dependent, global threat to many crops of high socio-economic value, including grapevine. Currently designed breeding strategies for Xf-tolerant or -resistant genotypes insufficiently address the danger of biodiversity loss by focusing on selected threats, neglecting future environmental conditions. Thus, breeding strategies should be validated across diverse populations and acknowledge temperature changes and drought by minimizing the metabolic-physiologic effects of multiple stress-induced oxygen shortages. This research hypothesizes that multiple-resilient plant holobionts achieve lifelong adaptive robustness through early molecular and metabolic responses in primary stress target cells, which facilitate efficient respiration adjustment and cell cycle down-regulation. To validate this concept open-access transcriptome data were analyzed of xylem tissues of Xf-tolerant and -resistant Vitis holobionts from diverse trials and genetic origins from early hours to longer periods after Xf-inoculation. The results indicated repetitive involvement of alternative oxidase (AOX) transcription in episodes of down-regulated transcripts of cytochrome c oxidase (COX) at various critical time points before disease symptoms emerged. The relation between transcript levels of COX and AOX ('relCOX/AOX') was found promising for plant discrimination and primer screening. Furthermore, transcript levels of xylem-harbored bacterial consortia indicated common regulation with Xf and revealed stress-induced early down-regulation and later enhancement. LPS priming promoted the earlier increase in bacterial transcripts after Xf-inoculation. This proof-of-principle study highlights a SMART perspective for AOX-assisted plant selection towards multiple-resilience that includes Xf-tolerance. It aims to support timely future plant diagnostics and in-field substitution, sustainable agro-management, which protects population diversity and strengthens both conventional breeding and high-tech, molecular breeding research. Furthermore, the results suggested early up-regulation of bacterial microbiota consortia in vascular-enriched tissues as a novel additional trait for future studies on Xf-tolerance.


Assuntos
Proteínas Mitocondriais , Oxirredutases , Doenças das Plantas , Proteínas de Plantas , Vitis , Xylella , Xylella/genética , Xylella/fisiologia , Vitis/microbiologia , Vitis/genética , Oxirredutases/genética , Oxirredutases/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Regulação da Expressão Gênica de Plantas , Família Multigênica , Xilema/microbiologia , Xilema/genética
10.
Plant Cell Rep ; 43(6): 152, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806834

RESUMO

KEY MESSAGE: Sodium nitroprusside mediates drought stress responses in tomatoes by modulating nitrosative and oxidative pathways, highlighting the interplay between nitric oxide, hydrogen sulfide, and antioxidant systems for enhanced drought tolerance. While nitric oxide (NO), a signalling molecule, enhances plant tolerance to abiotic stresses, its precise contribution to improving tomato tolerance to drought stress (DS) through modulating oxide-nitrosative processes is not yet fully understood. We aimed to examine the interaction of NO and nitrosative signaling, revealing how sodium nitroprusside (SNP) could mitigate the effects of DS on tomatoes. DS-seedlings endured 12% polyethylene glycol (PEG) in a 10% nutrient solution (NS) for 2 days, then transitioned to half-strength NS for 10 days alongside control plants. DS reduced total plant dry weight, chlorophyll a and b, Fv/Fm, leaf water potential (ΨI), and relative water content, but improved hydrogen peroxide (H2O2), proline, and NO content. The SNP reduced the DS-induced H2O2 generation by reducing thiol (-SH) and the carbonyl (-CO) groups. SNP increased not only NO but also the activity of L-cysteine desulfhydrase (L-DES), leading to the generation of H2S. Decreases in S-nitrosoglutathione reductase (GSNOR) and NADPH oxidase (NOX) suggest a potential regulatory mechanism in which S-nitrosylation [formation of S-nitrosothiol (SNO)] may influence protein function and signaling pathways during DS. Moreover, SNP improved ascorbate (AsA) and glutathione (GSH) and reduced oxidized glutathione (GSSG) levels in tomato plants under drought. Furthermore, the interaction of NO and H2S, mediated by L-DES activity, may serve as a vital cross-talk mechanism impacting plant responses to DS. Understanding these signaling interactions is crucial for developing innovative drought-tolerance strategies in crops.


Assuntos
Secas , Peróxido de Hidrogênio , Óxido Nítrico , Nitroprussiato , Solanum lycopersicum , Nitroprussiato/farmacologia , Solanum lycopersicum/fisiologia , Solanum lycopersicum/metabolismo , Solanum lycopersicum/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Glutationa/metabolismo , Antioxidantes/metabolismo , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/fisiologia , Plântula/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Nitrosação/efeitos dos fármacos , Clorofila/metabolismo
11.
J Nanobiotechnology ; 22(1): 17, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172992

RESUMO

There is a growing body of evidence indicating a close association between inflammatory bowel disease (IBD) and disrupted intestinal homeostasis. Excessive production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), along with an increase in M1 proinflammatory macrophage infiltration during the activation of intestinal inflammation, plays a pivotal role in disrupting intestinal homeostasis in IBD. The overabundance of ROS/RNS can cause intestinal tissue damage and the disruption of crucial gut proteins, which ultimately compromises the integrity of the intestinal barrier. The proliferation of M1 macrophages contributes to an exaggerated immune response, further compromising the intestinal immune barrier. Currently, intestinal nanomaterials have gained widespread attention in the context of IBD due to their notable characteristics, including the ability to specifically target regions of interest, clear excess ROS/RNS, and mimic biological enzymes. In this review, we initially elucidated the gut microenvironment in IBD. Subsequently, we delineate therapeutic strategies involving two distinct types of nanomedicine, namely inorganic nanoparticles and natural product nanomaterials. Finally, we present a comprehensive overview of the promising prospects associated with the application of nanomedicine in future clinical settings for the treatment of IBD (graphic abstract). Different classes of nanomedicine are used to treat IBD. This review primarily elucidates the current etiology of inflammatory bowel disease and explores two prominent nanomaterial-based therapeutic approaches. First, it aims to eliminate excessive reactive oxygen species and reactive nitrogen species. Second, they focus on modulating the polarization of inflammatory macrophages and reducing the proportion of pro-inflammatory macrophages. Additionally, this article delves into the treatment of inflammatory bowel disease using inorganic metal nanomaterials and natural product nanomaterials.


Assuntos
Produtos Biológicos , Doenças Inflamatórias Intestinais , Nanopartículas , Humanos , Espécies Reativas de Oxigênio/metabolismo , Doenças Inflamatórias Intestinais/tratamento farmacológico , Espécies Reativas de Nitrogênio/metabolismo
12.
Mikrochim Acta ; 191(9): 523, 2024 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112841

RESUMO

An antifouling peptide hydrogel-based electrochemical biosensor was developed for real-time monitoring of hydrogen peroxide (H2O2) and nitric oxide (NO) released by 3D cultured breast cancer cells upon drug stimulation. Platinum nanoparticles (Pt NPs) were electrodeposited on titanium mesh (Pt NPs/TM) to enhance sensitivity and shown to possess excellent electrocatalytic ability toward H2O2 and NO. The composite hydrogel formed by co-assembling of N-fluorenylmethoxycarbonyl diphenylalanine (Fmoc-FF) and a fluorine methoxycarbonyl group-functionalized Lys-(Fmoc)-Asp was coated on Pt NPs/TM electrode surface to provide cellular scaffolding. Their favorable biocompatibility promoted cell adhesion and growth, while good hydrophilicity endowed the sensor with greatly enhanced antifouling capability in complex cell culture environments. The biosensor successfully determined H2O2 and NO secretion from both non-metastatic and metastatic breast cancer cells in real time. Our results demonstrated robust associations between reactive oxygen species (ROS) and reactive nitrogen species (RNS) production and cell malignancy, with the main difference in oxidative stress between the two subtypes of cells being NO release, particularly emphasizing RNS's critical leading in driving cancer metastasis and invasion progression. This sensor holds great potential for cell-release research under the in vivo-like microenvironment and could reveal RNS as an attractive therapeutic target for treating breast cancer.


Assuntos
Técnicas Biossensoriais , Neoplasias da Mama , Técnicas Eletroquímicas , Hidrogéis , Peróxido de Hidrogênio , Óxido Nítrico , Platina , Humanos , Técnicas Biossensoriais/métodos , Peróxido de Hidrogênio/química , Hidrogéis/química , Neoplasias da Mama/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico/análise , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Platina/química , Nanopartículas Metálicas/química , Feminino , Peptídeos/química , Peptídeos/farmacologia , Linhagem Celular Tumoral , Titânio/química , Células MCF-7 , Técnicas de Cultura de Células em Três Dimensões/métodos
13.
Int J Mol Sci ; 25(15)2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39126104

RESUMO

Melatonin regulates vital physiological processes in animals, such as the circadian cycle, sleep, locomotion, body temperature, food intake, and sexual and immune responses. In plants, melatonin modulates seed germination, longevity, circadian cycle, photoperiodicity, flowering, leaf senescence, postharvest fruit storage, and resistance against biotic and abiotic stresses. In plants, the effect of melatonin is mediated by various regulatory elements of the redox network, including RNS and ROS. Similarly, the radical gas NO mediates various physiological processes, like seed germination, flowering, leaf senescence, and stress responses. The biosynthesis of both melatonin and NO takes place in mitochondria and chloroplasts. Hence, both melatonin and nitric oxide are key signaling molecules governing their biological pathways independently. However, there are instances when these pathways cross each other and the two molecules interact with each other, resulting in the formation of N-nitrosomelatonin or NOMela, which is a nitrosated form of melatonin, discovered recently and with promising roles in plant development. The interaction between NO and melatonin is highly complex, and, although a handful of studies reporting these interactions have been published, the exact molecular mechanisms governing them and the prospects of NOMela as a NO donor have just started to be unraveled. Here, we review NO and melatonin production as well as RNS-melatonin interaction under normal and stressful conditions. Furthermore, for the first time, we provide highly sensitive, ozone-chemiluminescence-based comparative measurements of the nitric oxide content, as well as NO-release kinetics between NOMela and the commonly used NO donors CySNO and GSNO.


Assuntos
Melatonina , Óxido Nítrico , Plantas , Melatonina/metabolismo , Óxido Nítrico/metabolismo , Plantas/metabolismo , Doadores de Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/farmacologia , Transdução de Sinais , Fenômenos Fisiológicos Vegetais
14.
Int J Mol Sci ; 25(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39201563

RESUMO

Nitric oxide (NO) has been firmly established as a key signaling molecule in plants, playing a significant role in regulating growth, development and stress responses. Given the imperative of sustainable agriculture and the urgent need to meet the escalating global demand for food, it is imperative to safeguard crop plants from the effects of climate fluctuations. Plants respond to environmental challenges by producing redox molecules, including reactive oxygen species (ROS) and reactive nitrogen species (RNS), which regulate cellular, physiological, and molecular processes. Nitric oxide (NO) plays a crucial role in plant stress tolerance, acting as a signaling molecule or free radical. NO is involved in various developmental processes in plants through diverse mechanisms. Exogenous NO supplementation can alleviate the toxicity of abiotic stresses and enhance plant resistance. In this review we summarize the studies regarding the production of NO in peroxisomes, and how its molecule and its derived products, (ONOO-) and S-nitrosoglutathione (GSNO) affect ROS metabolism in peroxisomes. Peroxisomal antioxidant enzymes including catalase (CAT), are key targets of NO-mediated post-translational modification (PTM) highlighting the dynamic metabolism of ROS and RNS in peroxisomes.


Assuntos
Óxido Nítrico , Peroxissomos , Processamento de Proteína Pós-Traducional , Espécies Reativas de Nitrogênio , Espécies Reativas de Oxigênio , Peroxissomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Óxido Nítrico/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Plantas/metabolismo
15.
Molecules ; 29(13)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38999186

RESUMO

Panax notoginseng is a highly valued perennial medicinal herb in China and is widely used in clinical treatments. The main purpose of this study was to elucidate the changes in the composition of P. notoginseng saponins (PNSs), which are the main bioactive substances, triggered by arbuscular mycorrhizal fungi (AMF) via ultrahigh-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS). A total of 202 putative terpenoid metabolites were detected, of which 150 triterpene glycosides were identified, accounting for 74.26% of the total. Correlation analysis, principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) of the metabolites revealed that the samples treated with AMF (group Ce) could be clearly separated from the CK samples. In total, 49 differential terpene metabolites were identified between the Ce and CK groups, of which 38 and 11 metabolites were upregulated and downregulated, respectively, and most of the upregulated differentially abundant metabolites were mainly triterpene glycosides. The relative abundances of the two major notoginsenosides (MNs), ginsenosides Rd and Re, and 13 rare notoginsenosides (RNs), significantly increased. The differential saponins, especially RNs, were more easily clustered into one branch and had a high positive correlation. It could be concluded that the biosynthesis and accumulation of some RNs share the same pathways as those triggered by AMF. This study provides a new way to obtain more notoginsenoside resources, particularly RNs, and sheds new light on the scientization and rationalization of the use of AMF agents in the ecological planting of medicinal plants.


Assuntos
Metabolômica , Micorrizas , Panax notoginseng , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Triterpenos , Panax notoginseng/microbiologia , Panax notoginseng/química , Triterpenos/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Micorrizas/metabolismo , Metabolômica/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Saponinas/metabolismo , Saponinas/química , Análise de Componente Principal , Metaboloma
16.
Plant Cell Physiol ; 63(12): 1764-1786, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-34910215

RESUMO

Melatonin, a tryptophan-derived molecule, is endogenously generated in animal, plant, fungal and prokaryotic cells. Given its antioxidant properties, it is involved in a myriad of signaling functions associated with various aspects of plant growth and development. In higher plants, melatonin (Mel) interacts with plant regulators such as phytohormones, as well as reactive oxygen and nitrogen species including hydrogen peroxide (H2O2), nitric oxide (NO) and hydrogen sulfide (H2S). It shows great potential as a biotechnological tool to alleviate biotic and abiotic stress, to delay senescence and to conserve the sensory and nutritional quality of postharvest horticultural products which are of considerable economic importance worldwide. This review provides a comprehensive overview of the biochemistry of Mel, whose endogenous induction and exogenous application can play an important biotechnological role in enhancing the marketability and hence earnings from postharvest horticultural crops.


Assuntos
Melatonina , Melatonina/farmacologia , Peróxido de Hidrogênio , Antioxidantes , Produtos Agrícolas , Reguladores de Crescimento de Plantas/farmacologia
17.
Small ; 19(41): e2302331, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37246260

RESUMO

A therapeutic strategy that could address colitis of multiple etiologies while restoring the dysbiosis of gut microbiota is attractive. Here, Aurozyme, a novel nanomedicine comprised of gold nanoparticles (AuNPs) and glycyrrhizin (GL) with a glycol chitosan coating layer, as a promising approach for colitis, is demonstrated. The unique feature of Aurozyme is the conversion of harmful peroxidase-like activity of AuNPs to beneficial catalase-like activity due to the amine-rich environment provided by the glycol chitosan. This conversion process enables Aurozyme to oxidize the hydroxyl radicals derived from AuNP, producing water and oxygen molecules. In fact, Aurozyme effectively scavenges reactive oxygen/reactive nitrogen species (ROS/RNS) and damage-associated molecular patterns (DAMPs), which can attenuate the M1 polarization of macrophage. It exhibits prolonged adhesion to the lesion site, promoting sustained anti-inflammatory effects and restoring intestinal function in colitis-challenged mice. Additionally, it increases the abundance and diversity of beneficial probiotics, which are essential for maintaining microbial homeostasis in the gut. The work highlights the transformative potential of nanozymes for the comprehensive treatment of inflammatory disease and represents an innovative switching technology of enzyme-like activity by Aurozyme.


Assuntos
Colite , Nanopartículas Metálicas , Camundongos , Animais , Peroxidase , Catalase , Ouro , Colite/tratamento farmacológico , Antioxidantes , Espécies Reativas de Oxigênio , Oxigênio
18.
Epilepsia ; 64(4): 811-820, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36727550

RESUMO

OBJECTIVE: There are three neurostimulation devices available to treat generalized epilepsy: vagus nerve stimulation (VNS), deep brain stimulation (DBS), and responsive neurostimulation (RNS). However, the choice between them is unclear due to lack of head-to-head comparisons. A systematic comparison of neurostimulation outcomes in generalized epilepsy has not been performed previously. The goal of this meta-analysis was to determine whether one of these devices is better than the others to treat generalized epilepsy. METHODS: Following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a systematic review of PubMed, Embase, and Web of Science was performed for studies reporting seizure outcomes following VNS, RNS, and DBS implantation in generalized drug-resistant epilepsy between the first pivotal trial study for each modality through August 2022. Specific search criteria were used for VNS ("vagus", "vagal", or "VNS" in the title and "epilepsy" or "seizure"), DBS ("deep brain stimulation", "DBS", "anterior thalamic nucleus", "centromedian nucleus", or "thalamic stimulation" in the title and "epilepsy" or "seizure"), and RNS ("responsive neurostimulation" or "RNS" in the title and "epilepsy" or "seizure"). From 4409 articles identified, 319 underwent full-text reviews, and 20 studies were included. Data were pooled using a random-effects model using the meta package in R. RESULTS: Sufficient data for meta-analysis were available from seven studies for VNS (n = 510) and nine studies for DBS (n = 87). Data from RNS (five studies, n = 18) were insufficient for meta-analysis. The mean (SD) follow-up durations were as follows: VNS, 39.1 (23.4) months; DBS, 23.1 (19.6) months; and RNS, 22.3 (10.6) months. Meta-analysis showed seizure reductions of 48.3% (95% confidence interval [CI] = 38.7%-57.9%) for VNS and 64.8% (95% CI = 54.4%-75.2%) for DBS (p = .02). SIGNIFICANCE: Our meta-analysis indicates that the use of DBS may lead to greater seizure reduction than VNS in generalized epilepsy. Results from RNS use are promising, but further research is required.


Assuntos
Núcleos Anteriores do Tálamo , Epilepsia Resistente a Medicamentos , Epilepsia Generalizada , Epilepsia , Estimulação do Nervo Vago , Humanos , Epilepsia/terapia , Epilepsia Resistente a Medicamentos/terapia , Convulsões/terapia , Epilepsia Generalizada/terapia , Estimulação do Nervo Vago/métodos , Resultado do Tratamento
19.
Cell Biol Int ; 47(2): 327-340, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36342241

RESUMO

The serious problems of conventional breast cancer therapy strategies such as drug resistance, severe side effects, and lack of selectivity prompted the development of various cold atmospheric plasma (CAP) devices. Due to its advanced technology, CAP can produce a unique environment rich in reactive oxygen and nitrogen species (RONS), photons, charged ions, and an electric field, making it a promising revolutionary platform for cancer therapy. Despite substantial technological successes, CAP-based therapeutic systems are encounter with distinct limitations, including low control of the generated RONS, poor knowledge about its anticancer mechanisms, and challenges concerning designing, manufacturing, clinical translation, and commercialization, which must be resolved. The latest developments in CAP-based therapeutic systems for breast cancer treatment are discussed in this review. More significantly, the integration of CAP-based medicine approaches with other breast cancer therapies, including chemo- and nanotherapy is thoroughly addressed.


Assuntos
Neoplasias da Mama , Gases em Plasma , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Gases em Plasma/uso terapêutico , Espécies Reativas de Oxigênio , Espécies Reativas de Nitrogênio , Oxigênio
20.
Epilepsy Behav ; 142: 109182, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36972642

RESUMO

OBJECTIVES: Different neurostimulation modalities are available to treat drug-resistant focal epilepsy when surgery is not an option including vagus nerve stimulation (VNS), responsive neurostimulation (RNS), and deep brain stimulation (DBS). Head-to-head comparisons of efficacy do not exist between them nor are likely to be available in the future. We performed a meta-analysis on VNS, RNS, and DBS outcomes to compare seizure reduction efficacy for focal epilepsy. METHODS: We systematically reviewed the literature for reported seizure outcomes following implantation with VNS, RNS, and DBS in focal-onset seizures and performed a meta-analysis. Prospective or retrospective clinical studies were included. RESULTS: Sufficient data were available at years one (n = 642, two (n = 480), and three (n = 385) for comparing the three modalities with each other. Seizure reduction for the devices at years one, two, and three respectively were: RNS: 66.3%, 56.0%, 68.4%; DBS- 58.4%, 57.5%, 63.8%; VNS 32.9%, 44.4%, 53.5%. Seizure reduction at year one was greater for RNS (p < 0.01) and DBS (p < 0.01) compared to VNS. CONCLUSIONS: Our findings indicate the seizure reduction efficacy of RNS is similar to DBS, and both had greater seizure reductions compared to VNS in the first-year post-implantation, with the differences diminishing with longer-term follow-up. SIGNIFICANCE: The results help guide neuromodulation treatment in eligible patients with drug-resistant focal epilepsy.


Assuntos
Estimulação Encefálica Profunda , Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Estimulação do Nervo Vago , Humanos , Estudos Retrospectivos , Estudos Prospectivos , Estimulação Encefálica Profunda/métodos , Epilepsias Parciais/terapia , Epilepsia Resistente a Medicamentos/terapia , Convulsões/terapia , Estimulação do Nervo Vago/métodos , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA