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1.
Int J Mol Sci ; 22(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068540

RESUMO

Spodopteraexigua, a multifeeding insect pest, has developed a high level of resistance to chlorantraniliprole, which is a benzoylurea insecticide that targets the ryanodine receptors (RyRs). Herein, the resistant strain (SE-Sel) and sensitive strain (SE-Sus) were obtained by bidirectional screening for six generations. The potential oviposited eggs and oviposition rate of the SE-Sel strain were dramatically lower than those of the SE-Sus strain; on the contrary, the weights of prepupae and preadult were significantly increased. As a post-mating response, the higher number of non-oviposited eggs in the SE-Sel strain was caused by a lower mating rate. In addition, the expression levels of vitellogenin (SeVg) and its receptor (SeVgR) in the SE-Sel strain were consistently lower than those in the SE-Sus strain. An RyRI4743M mutation, contributing to the resistance to chlorantraniliprole, was located in the S3 transmembrane segments and might have affected the release of calcium ions; it led to the upregulated expression of the neuropeptide SeNPF and its receptor SeNPFR, and the mating and oviposition rate were significantly recovered when the SeNPF was knocked down though RNA interference (RNAi) in the male adult of the SE-Sel strain. Moreover, the expression of the juvenile hormone-binding proteins SeJHBWDS3 and SeJHBAN in the male adult of the SE-Sel strain was significantly decreased, which proved the existence of a fitness cost from another angle. Therefore, these results indicate that the fitness cost accompanied by chlorantraniliprole resistance in S. exigua may be related to the decrease in mating desire due to SeNPF overexpression.


Assuntos
Proteínas de Insetos/genética , Resistência a Inseticidas/genética , Spodoptera/genética , ortoaminobenzoatos/farmacologia , Animais , Proteínas de Transporte/genética , Resistência à Doença/efeitos dos fármacos , Resistência à Doença/genética , Proteínas do Ovo/genética , Aptidão Genética/genética , Inseticidas/farmacologia , Mutação/genética , Neuropeptídeos/genética , Interferência de RNA , Receptores de Superfície Celular/genética , Receptores de Neuropeptídeos/genética , Spodoptera/efeitos dos fármacos , Vitelogeninas/genética , ortoaminobenzoatos/efeitos adversos
2.
Int J Mol Sci ; 22(8)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924175

RESUMO

Antithrombin (AT) is a natural anticoagulant that interacts with activated proteases of the coagulation system and with heparan sulfate proteoglycans (HSPG) on the surface of cells. The protein, which is synthesized in the liver, is also essential to confer the effects of therapeutic heparin. However, AT levels drop in systemic inflammatory diseases. The reason for this decline is consumption by the coagulation system but also by immunological processes. Aside from the primarily known anticoagulant effects, AT elicits distinct anti-inflammatory signaling responses. It binds to structures of the glycocalyx (syndecan-4) and further modulates the inflammatory response of endothelial cells and leukocytes by interacting with surface receptors. Additionally, AT exerts direct antimicrobial effects: depending on AT glycosylation it can bind to and perforate bacterial cell walls. Peptide fragments derived from proteolytic degradation of AT exert antibacterial properties. Despite these promising characteristics, therapeutic supplementation in inflammatory conditions has not proven to be effective in randomized control trials. Nevertheless, new insights provided by subgroup analyses and retrospective trials suggest that a recommendation be made to identify the patient population that would benefit most from AT substitution. Recent experiment findings place the role of various AT isoforms in the spotlight. This review provides an overview of new insights into a supposedly well-known molecule.


Assuntos
Antitrombinas/farmacologia , Resistência à Doença/efeitos dos fármacos , Suscetibilidade a Doenças , Interações Hospedeiro-Patógeno , Inflamação/etiologia , Inflamação/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antitrombinas/uso terapêutico , Biomarcadores , Gerenciamento Clínico , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Imunomodulação/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/patologia , Especificidade de Órgãos , Transdução de Sinais/efeitos dos fármacos
3.
Fish Shellfish Immunol ; 113: 96-105, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33826939

RESUMO

The present study was conducted to investigate the effects of dietary cinnamaldehyde nanoemulsion (CNE) on growth, digestive activities, antioxidant and immune responses and resistance against Streptococcus agalactiae (S. agalactiae) in Nile tilapia. Four experimental diets were formulated containing CNE at levels of 0, 100, 200 and 300 mg/kg diet for 12 weeks. At the end of the experiment, all fish were challenged by S. agalactiae. The results showed that the final body weight was increased in fish groups fed 200 and 300 mg CNE/kg diet by 18.4 and 17.2% with respect to the control group. Moreover, feed conversion ratio and digestive enzymes' activities were improved in groups fed 200 and 300 then 100 mg of dietary CNE/kg diet. Groups fed CNE exhibited a significant increase in serum immune-related parameters when compared with control group. Additionally, the hypocholesterolemic effects was achieved after CNE feeding unlike the control group in a dose dependent manner. With increasing dietary CNE levels, genes expression of cytokines and antioxidant enzymes were upregulated. Less severe adverse clinical symptoms and respectable cumulative mortalities associated with S. agalactiae infection were observed in fish fed CNE. To our knowledge, this study was the first offering a protective effect of CNE against S. agalactiae infection in Nile tilapia with a maximum down-regulation of cylE and hylB virulence genes expression noticed in group fed 300 mg of CNE/kg diet (up to 0.10 and 0.19- fold, respectively). Therefore, the present study recommended that an incorporation of CNE at level of 300 mg/kg diet for Nile tilapia could promote their growth, enhance their immunity and antioxidant status and provide protection against virulent S. agalactiae.


Assuntos
Acroleína/análogos & derivados , Antioxidantes/metabolismo , Ciclídeos/imunologia , Doenças dos Peixes/imunologia , Imunidade Inata/genética , Nanoestruturas/administração & dosagem , Infecções Estreptocócicas/veterinária , Acroleína/administração & dosagem , Acroleína/metabolismo , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/efeitos dos fármacos , Resistência à Doença/imunologia , Relação Dose-Resposta a Droga , Emulsões/administração & dosagem , Infecções Estreptocócicas/imunologia , Streptococcus agalactiae/fisiologia
4.
Fish Shellfish Immunol ; 112: 56-63, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33640538

RESUMO

The effects of dietary ß-glucan on innate immune responses have been shown in a number of different vertebrate species. However, there is conflicting information about the period of administration (shorter vs. longer), and it is also unclear to what extent ß-glucan's effects can be observed post-treatment in fish. Thus, we fed Nile tilapia for 0 (control group; 45 days of control diet), 15 (30 days of control followed by 15 days of ß-glucan), 30 (15 days of control followed by 30 days of ß-glucan) or 45 days with a diet containing 0.1% of ß-glucan (MacroGard®). We evaluated the growth performance at the end of the ß-glucan feeding trial and the innate immune function immediately after the feeding trial and 7 and 14 days post-feeding trial. In addition, at day 10 post-feeding trial, we assessed the tilapia's resistance against a bacterial infection. No significant differences were observed in growth performance between the groups; however, fish fed with ß-glucan for 30 and 45 days had higher (approx. 8%) relative weight gain compared to the control. Regardless of the administration period, fish fed with ß-glucan had higher innate immune responses immediately after the feeding trial such as lysozyme activity in plasma, liver and intestine and respiratory burst compared to the control, and in general these differences were gradually reduced over the withdrawal period (up to 14 days). No differences were observed in the plasma hemolytic activity of the complement or myeloperoxidase activity in plasma or intestine. Moreover, fish from the control group had early mortalities (2 vs. 4-5 days post-infection, respectively) and a lower survival rate (60 vs. 80%, respectively) compared to fish fed with ß-glucan for 15 or 30 days, and, interestingly, fish fed for 45 days with ß-glucan had no mortality. This study indicates that regardless of the administration period (i.e., 15 up to 45 days), the ß-glucan improved the innate immune responses and the tilapia's resistance to disease, and this protection could be observed up to 10 days post-feeding trial, adding in vivo evidence that ß-glucan may contribute to a trained innate immunity. Additionally, we showed that a longer period of administration did not cause immunosuppression as previously hypothesized but promoted further growth and immune performance. These findings are relevant to the aquaculture industry and demonstrate that a longer ß-glucan feeding protocol may be considered to achieve better results.


Assuntos
Ciclídeos/imunologia , Resistência à Doença/efeitos dos fármacos , Doenças dos Peixes/imunologia , Imunidade Inata/efeitos dos fármacos , beta-Glucanas/metabolismo , Aeromonas/fisiologia , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/imunologia , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/veterinária , Distribuição Aleatória , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/fisiologia , beta-Glucanas/administração & dosagem
5.
Arch Microbiol ; 203(4): 1641-1647, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33432379

RESUMO

To investigate the molecular mechanism of Trichoderma L-amino acid oxidase (Th-LAAO) in protecting and in promoting growth of cabbage infected with Botrytis cinerea, a three-way interaction system was established. Cabbage leaves treated with purified Th-LAAO significantly constrained damaged leaf area caused by B. cinerea infection. In response to Th-LAAO treatment, the expression levels of genes involved in photosynthesis, such as ribulose-1,5-bisphosphate carboxylase oxygenase, Rubisco activase, and ATP synthase increased 2.54, 2.18, and 1.41 folds, respectively. The transcription levels of sucrose transport protein 1 increased 7.6 fold. As to the expression of defense-related genes, the transcription level of ascorbate peroxidase increased 1.46 fold. On the contrary, pathogenesis-related protein 1, chitinase, ß-1,3 glucanase, and glutathione S-transferase decreased significantly. Overall, the results indicated that Th-LAAO may stimulate CO2 fixation and sucrose transport and elicit host defense responses in cabbage against B. cinerea, and this elicitation of defense response is likely to contribute to induced systemic resistance of host plant.


Assuntos
Brassica , Resistência à Doença , L-Aminoácido Oxidase , Trichoderma , Botrytis/fisiologia , Brassica/efeitos dos fármacos , Brassica/genética , Brassica/microbiologia , Resistência à Doença/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , L-Aminoácido Oxidase/isolamento & purificação , L-Aminoácido Oxidase/farmacologia , Fotossíntese/efeitos dos fármacos , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/microbiologia , Trichoderma/química , Trichoderma/enzimologia
6.
Plant Sci ; 302: 110712, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33288019

RESUMO

Actin remodelling by a membrane-associated oxidative process can sense perturbations of membrane integrity and activate defence. In the current work, we show that glycyrrhizin, a muscle relaxant used in Traditional Chinese Medicine, can activate oxidative burst and actin remodelling in tobacco BY-2 cells, which could be suppressed by diphenylene iodonium, an inhibitor of NADPH oxidases. Glycyrrhizin caused a dose-dependent delay of proliferation, and induced cell death, which was suppressed by addition of indole-acetic acid, a natural auxin that can mitigate RboH dependent actin remodelling. To test, whether the actin remodelling induced by glycyrrhizin was followed by activation of defence, several events of basal immunity were probed. We found that glycyrrhizin induced a transient extracellular alkalinisation, indicative of calcium influx. Furthermore, transcripts of phytoalexins genes, were activated in cells of the grapevine Vitis rupestris, and this induction was followed by accumulation of the glycosylated stilbene α-piceid. We also observed that glycyrrhizin was able to induce actin bundling in leaves of a transgenic grape, especially in guard cells. We discuss these data in frame of a model, where glycyrrhizin, through stimulation of RboH, can cause actin remodelling, followed by defence responses, such as calcium influx, induction of phytoalexins transcripts, and accumulation of stilbene glycosides.


Assuntos
Actinas/metabolismo , Glycyrrhiza uralensis , Ácido Glicirrízico/farmacologia , Proteínas de Plantas/metabolismo , Vitis/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Resistência à Doença/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glycyrrhiza uralensis/química , Medicina Tradicional Chinesa , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Estilbenos/metabolismo , Tabaco/efeitos dos fármacos , Vitis/imunologia , Vitis/metabolismo
7.
PLoS One ; 15(8): e0236633, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32785249

RESUMO

The induction of general plant defense responses following the perception of external elicitors is now regarded as the first level of the plant immune response. Depending on the involvement or not of these molecules in pathogenicity, this induction of defense is called either Pathogen-Associated Molecular Pattern (PAMP) Triggered Immunity or Pattern Triggered Immunity-both abbreviated to PTI. Because PTI is assumed to be a widespread and stable form of resistance to infection, understanding the mechanisms driving it becomes a major goal for the sustainable management of plant-pathogen interactions. However, the induction of PTI is complex. Our hypotheses are that (i) the recognition by the plant of PAMPs vs non-PAMP elicitors leads to specific defense profiles and (ii) the responses specifically induced by PAMPs target critical life history traits of the pathogen that produced them. We thus analyzed, using a metabolomic approach coupled with transcriptomic and hormonal analyses, the defense profiles induced in potato foliage treated with either a Concentrated Culture Filtrate (CCF) from Phytophthora infestans or two non-PAMP preparations, ß-aminobutyric acid (BABA) and an Ulva spp. Extract, used separately. Each elicitor induced specific defense profiles. CCF up-regulated sesquiterpenes but down-regulated sterols and phenols, notably α-chaconine, caffeoyl quinic acid and rutin, which decreased spore production of P. infestans in vitro. CCF thus induces both defense and counter-defense responses. By contrast, the Ulva extract triggered the synthesis of a large-spectrum of antimicrobial compounds through the phenylpropanoid/flavonoid pathways, while BABA targeted the primary metabolism. Hence, PTI can be regarded as a heterogeneous set of general and pathogen-specific responses triggered by the molecular signatures of each elicitor, rather than as a uniform, non-specific and broad-spectrum set of general defense reactions.


Assuntos
Resistência à Doença/imunologia , Doenças das Plantas/imunologia , Imunidade Vegetal/imunologia , Solanum tuberosum/imunologia , Aminobutiratos/farmacologia , Resistência à Doença/efeitos dos fármacos , Flavonoides/biossíntese , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Fenóis/metabolismo , Phytophthora infestans/imunologia , Phytophthora infestans/patogenicidade , Doenças das Plantas/microbiologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Imunidade Vegetal/efeitos dos fármacos , Sesquiterpenos/metabolismo , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/microbiologia , Esteróis/metabolismo , Ulva/química
8.
Int J Food Microbiol ; 334: 108807, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-32835997

RESUMO

The main goal of this study was to describe impact of preharvest application of methyl salicylate (MeSA), acetyl salicylic acid (ASA) and salicylic acid (SA) on the reduction of disease caused by Botrytis cinerea in two table grape cultivars ('Crimson' and 'Magenta'). Based on previous studies, MeSA and SA were applied at 0.1 and 0.01 mM for both cultivars, while ASA was applied at 1 mM in 'Crimson' and 0.1 mM in 'Magenta'. At time of harvest, berry maturity-quality attributes, bioactive compounds and antioxidant enzymes were determined. In addition, grapes were artificially inoculated with B. cinerea spores, and the berries were ranked for visual decay incidence after 5 days of inoculation. Salicylates preharvest treatments led to higher total acidity, content of bioactive compounds and activity of antioxidant enzymes in treated than in control berries. The application of salicylate derivatives induced resistance to B. cinerea spoilage, since higher percentage of berries with no symptoms was observed and on the contrary, the highest percentages of berries were obtained in control grapes. All preharvest treatments with SA, ASA and MeSA alleviated postharvest disease caused by B. cinerea probably due to increasing levels of phenolic compounds and activity of antioxidant enzymes, although the best results were obtained with MeSA at 0.1 mM. Also, for this treatment and dose, higher quality properties, such as higher concentrations of ascorbic, succinic and fumaric acids, were observed compared with no treated-grapes.


Assuntos
Antioxidantes/metabolismo , Botrytis/efeitos dos fármacos , Doenças das Plantas/prevenção & controle , Ácido Salicílico/farmacologia , Vitis/microbiologia , Aspirina/farmacologia , Resistência à Doença/efeitos dos fármacos , Conservação de Alimentos/métodos , Fenóis/metabolismo , Doenças das Plantas/microbiologia , Salicilatos/farmacologia , Vitis/efeitos dos fármacos , Vitis/metabolismo
9.
Tohoku J Exp Med ; 251(3): 175-181, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32641644

RESUMO

The novel coronavirus disease 2019 (COVID-19) is now officially declared as a pandemic by the World Health Organization (WHO), and most parts of the world are taking drastic measures to restrict human movements to contain the infection. Millions around the world are wondering, if there is anything that could be done, other than maintaining high personal hygiene, and be vigilant of the symptoms, to reduce the spread of the disease and chances of getting infected, or at least to lessen the burden of the disease, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The National and International health agencies, including the National Institutes of Health (NIH), the Centers for Disease Control and Prevention (CDC), and the WHO have provided clear guidelines for both preventive and treatment suggestions. In this article, I will briefly discuss, why keeping adequate zinc balance might enhance the host response and be protective of viral infections.


Assuntos
Betacoronavirus , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Zinco/fisiologia , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/uso terapêutico , Fatores Etários , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/fisiologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Suplementos Nutricionais , Resistência à Doença/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Sistema Imunitário/efeitos dos fármacos , Micronutrientes/fisiologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/imunologia , Replicação Viral/efeitos dos fármacos , Zinco/administração & dosagem , Zinco/deficiência , Zinco/farmacologia
10.
Aquat Toxicol ; 224: 105494, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32422488

RESUMO

Little is known about the impacts of dietary exposure to inorganic mercury (Hg) for a long duration on the health indicators, growth, and disease resistance in Oreochromis niloticus. Accordingly, the current study was designed to assess the effects of Hg contaminated diets on blood biochemistry, growth, chemical composition, Hg bioaccumulation in the tissues, histopathology of liver and head kidneys, and disease resistance to Aeromonas hydrophila of O. niloticus. Also, the efficiency of citronella oil, geranium oil (GO), curcumin (CUR), Bacillus toyonensis (BT), and Bacillus subtilis (BS) as dietary supplements on reversing the negative impacts of Hg were assessed. A total of 240 tilapia fingerlings were assigned to eight dietary treatments fed on the basal diet (G1), G1 diet contaminated with 50 ppm Hg (G2), whereas the other groups fed the G2 diet and enriched with 400 mg CO (G3), 400 mg GO (G4), 200 mg CUR (G5), 7 × 107 cells BT (G6), 7 × 107 cells BS (G7), and 7 × 107 BT + BS/ kg diet (G8) for 16 weeks. The obtained results showed that fish fed on the G2 diet had significantly impaired growth performance indicators, blood parameters, and resistance to bacterial infection compared with fish in the control group. Additionally, distinct pathological perturbations in liver and head kidneys were observed. In contrast, fish groups G3 to G8 had a significant enhancement in the growth performance, Hg bioaccumulation in fish tissues, blood biochemistry, and resistance against A. hydrophila infection compared with fish in the G2 group. Maximum improvement was recorded in G5, G6, and G8. Conclusively, from both health and an economic point of view, these results suggested that several benefits might be gained by adding these additives, especially CUR, BT, and BT + BS, on growth enhancement and ameliorating Hg negative impacts in O. niloticus.


Assuntos
Ração Animal/análise , Bioacumulação , Ciclídeos/crescimento & desenvolvimento , Resistência à Doença/efeitos dos fármacos , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Negativas/veterinária , Mercúrio/toxicidade , Poluentes Químicos da Água/toxicidade , Aeromonas hydrophila/patogenicidade , Animais , Ciclídeos/imunologia , Ciclídeos/microbiologia , Dieta , Suplementos Nutricionais , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Rim Cefálico/efeitos dos fármacos , Rim Cefálico/metabolismo , Rim Cefálico/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Mercúrio/metabolismo , Poluentes Químicos da Água/metabolismo
11.
Sci Rep ; 10(1): 7467, 2020 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-32366860

RESUMO

High temperature inhibits wheat grain filling. Polyamines (PAs) are closely associated with plant resistance caused by abiotic stress. However, little is known about the effect of PAs on the grain filling of wheat under heat stress. Two wheat varieties differing in heat resistance were used, and endogenous PAs levels were measured during grain filling under normal growth conditions outside the greenhouse (CK), artificially simulated high temperature (HT), artificially simulated high temperature plus exogenous application of spermine (HT + Spm) and artificially simulated high temperature plus spermidine (HT + Spd) treatments. Additionally, the variation of antioxidant enzymatic activities and osmotic adjustable substances content in grains was measured during grain filling. The results showed that compared with HT,HT + Spm and HT + Spd significantly increased grain weight of XC 6 (heat-resistant variety) by 19% and 5%, and XC 31 (heat-sensitive variety) by 31% and 34%, activity of superoxide dismutase (SOD), peroxidase (POD)and catalase (CAT) and content of Spm, Spd, and proline (Pro) increased significantly, while putrescine (Put), malondialdehyde (MDA) and soluble sugar (SS)contentdecreased during grain filling; The correlation analysis showed that grain weight was negatively correlated with the content of PUT, MDA, Pro and activity of SOD and CAT and positively correlated with the content of Spd and activity of POD in grains. Our results indicated that exogenous Spm and Spd could alleviate the heat injury of grain filling.


Assuntos
Resistência à Doença/efeitos dos fármacos , Resposta ao Choque Térmico/efeitos dos fármacos , Temperatura Alta , Espermidina/farmacologia , Espermina/farmacologia , Triticum/crescimento & desenvolvimento , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo
12.
Int J Mol Sci ; 21(5)2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32155845

RESUMO

Jasmonates (JAs), the group of lipid-derived hormones, were found to control the defense responses in a myriad of plants. Meaningfully, the macrolactones of 12-hydroxy jasmonate isoleucine (12OH-JA-Ile) were reported to induce the defensive response of wild tobacco. However, little to nothing has been known about the elicitation effect of JA-Ile-macrolactones on woody plants to harmful organisms, let alone its underlying mechanisms. Here, we first optimized the synthetic routine using mild toxic reagent isobutyl chloroformate instead of ethyl chloroformate for conjugation, and we used acetonitrile (MeCN) instead of ethyl alcohol for the better dissolution of p-toluenesulfonic acid (p-TsOH) to gain JA-Ile-macrolactones. JA-Ile-macrolactone 5b-treated tea plants significantly inhibited the larvae weight gain of Ectropis obliqua larvae and the lesions caused by Colletotrichum camelliae. Furthermore, the expression level of CsOPR3 was significantly upregulated in 5b-treated leaves. Meanwhile, 5b reduced the accumulation of eriodictyol 7-O-glucuronide (EDG) in tea plants, which was confirmed to promote the growth rate of E. obliqua larvae by artificial diet assay. In conclusion, our study proved that the exogenous application of 5b could induce the tea plant resistance both to herbivore E. obliqua and pathogen C. camelliae, and EDG was identified as one of the secondary metabolites that could influence the growth rate of E. obliqua, but it did not directly influence the infection of C. camelliae in vitro. Further research should be carried out to clarify the mechanism through which 5b induces tea plant resistance to C. camelliae.


Assuntos
Camellia sinensis/efeitos dos fármacos , Colletotrichum/patogenicidade , Ciclopentanos/química , Resistência à Doença/efeitos dos fármacos , Isoleucina/análogos & derivados , Lactonas/farmacologia , Mariposas/patogenicidade , Doenças das Plantas/prevenção & controle , Animais , Camellia sinensis/genética , Camellia sinensis/imunologia , Camellia sinensis/microbiologia , Resistência à Doença/imunologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Herbivoria , Isoleucina/química , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/imunologia , Larva/microbiologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/imunologia , Folhas de Planta/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
13.
PLoS One ; 15(3): e0230362, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32176712

RESUMO

Fungi in the genus Cercospora cause crop losses world-wide on many crop species. The wide host range and success of these pathogens has been attributed to the production of a photoactivated toxin, cercosporin. We engineered tobacco for resistance to Cercospora nicotianae utilizing two strategies: 1) transformation with cercosporin autoresistance genes isolated from the fungus, and 2) transformation with constructs to silence the production of cercosporin during disease development. Three C. nicotianae cercosporin autoresistance genes were tested: ATR1 and CFP, encoding an ABC and an MFS transporter, respectively, and 71cR, which encodes a hypothetical protein. Resistance to the pathogen was identified in transgenic lines expressing ATR1 and 71cR, but not in lines transformed with CFP. Silencing of the CTB1 polyketide synthase and to a lesser extent the CTB8 pathway regulator in the cercosporin biosynthetic pathway also led to the recovery of resistant lines. All lines tested expressed the transgenes, and a direct correlation between the level of transgene expression and disease resistance was not identified in any line. Resistance was also not correlated with the degree of silencing in the CTB1 and CTB8 silenced lines. We conclude that expression of fungal cercosporin autoresistance genes as well as silencing of the cercosporin pathway are both effective strategies for engineering resistance to Cercospora diseases where cercosporin plays a critical role.


Assuntos
Ascomicetos/genética , Resistência à Doença/genética , Farmacorresistência Fúngica/genética , Inativação Gênica , Genes Fúngicos , Engenharia Genética , Perileno/análogos & derivados , Tabaco/microbiologia , Ascomicetos/efeitos dos fármacos , Resistência à Doença/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Perileno/farmacologia , Plantas Geneticamente Modificadas , Transformação Genética , Transgenes
14.
Plant Physiol Biochem ; 150: 263-269, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32171165

RESUMO

Tobacco mosaic virus (TMV) is one of the most damaging plant viruses from an economic and research point of view. Epigallocatechin-3-Gallate (EGCG), a flavonoid type secondary metabolite can selectively improve plant defense against pathogens; however, the effect of EGCG on plant defense against TMV and the underlying mechanism(s) remain elusive. In this study, exogenous EGCG application increased plant resistance to TMV as revealed by significantly decreased transcript levels of TMV-coat protein (CP) in tomato leaves. A time-course of H2O2 concentrations in tomato leaves showed that TMV inoculation rapidly increased the H2O2 accumulation, reaching its peak at 3 days post-inoculation (dpi) which remained the highest until 6 dpi. However, the combined treatment of EGCG and TMV remarkably decreased the concentrations of H2O2 at 3 and 6 dpi. Meanwhile, the transcript levels of RESPIRATORY BURST OXIDASE HOMOLOG 1 (SlRBOH1) were significantly increased by either EGCG or TMV inoculation, but the EGCG treatment along with TMV caused a further upregulation in the SlRBOH1 transcripts compared with that in only TMV-inoculated plants. Chemical scavenging of H2O2 or silencing SlRBOH1 both compromised the EGCG-induced enhanced resistance to TMV. Furthermore, EGCG-induced elevation in the activity of antioxidant enzymes was abolished by SlRBOH1 silencing, suggesting that EGCG enhanced defense against TMV by increasing the antioxidant enzyme activity via RBOH1-dependent H2O2 signaling. Taken together, our results suggest that EGCG functioned to maintain a delicate balance between ROS signaling and ROS scavenging via RBOH1, which enhanced tomato resistance to TMV.


Assuntos
Catequina/análogos & derivados , Resistência à Doença , Lycopersicon esculentum , Transdução de Sinais , Vírus do Mosaico do Tabaco , Catequina/farmacologia , Resistência à Doença/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Lycopersicon esculentum/virologia , Proteínas de Plantas/metabolismo , Transdução de Sinais/efeitos dos fármacos
15.
J Plant Physiol ; 246-247: 153129, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32050138

RESUMO

Micronutrients provide a potentially interesting alternative to fungicides for the protection of crops against fungal pathogens. Here we studied the effect of foliar-applied manganese (Mn) in the form of MnSO4 on severity of anthracnose disease, caused by Colletotrichum lagenarium in cucumber (Cucumis sativus L.) plant. The study was done aimed to characterize the optimum dose and application time of Mn fertilizer on disease suppression as well as to identify the defense mechanisms by which Mn-treated plants resist to fungal disease. In preliminary tests, Mn was applied at different concentrations (1.8, 4.5 and 7.2 mM) and various time points (three days before or two hours before inoculation, or three days after inoculation). Results showed that application of Mn either before or after inoculation suppressed the fungal infection in leaves and cotyledons, with a higher efficiency when applied three days prior to inoculation. However, all applied concentrations of Mn equally reduced the disease severity. Mn treatment in the absence of the pathogen promoted lignification and reactive oxygen species (ROS) accumulation. Also, pre-inoculation Mn treatment enhanced pathogen-induced lignification, callose or ROS production and reduced pathogen-induced cell death. The increase of lignin, callose and ROS induction by Mn application were 34, 30 and 31 % compared to control, respectively. Together, the results suggested the effectiveness of Mn treatments on anthracnose alleviation in cucumber plants. The findings here have a practical importance in plant physiology studies to identify the resistance-relevant mechanisms to pathogens and in sustainable agriculture to control the fungal diseases by a safe method.


Assuntos
Colletotrichum/fisiologia , Cucumis sativus/efeitos dos fármacos , Manganês/metabolismo , Doenças das Plantas/microbiologia , Cucumis sativus/metabolismo , Cucumis sativus/microbiologia , Resistência à Doença/efeitos dos fármacos , Manganês/administração & dosagem , Micronutrientes/administração & dosagem , Micronutrientes/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia
16.
Mol Plant Microbe Interact ; 33(4): 600-611, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31999214

RESUMO

The common bean rust fungus reduces harvests of the dry, edible common bean. Natural resistance genes in the plant can provide protection until a fungal strain that breaks resistance emerges. In this study, we demonstrate that benzo(1,2,3)thiadiazole-7-carbothioic acid S-methyl ester (BTH) sprayed on susceptible beans induces resistance to common bean rust. Protection occurred as soon as 72 h after treatment and resulted in no signs of disease 10 days after inoculation with rust spores. By contrast, the susceptible control plants sustained heavy infections and died. To understand the effect BTH has on the bean proteome, we measured the changes of accumulation for 3,973 proteins using mass spectrometry. The set of 409 proteins with significantly increased accumulation in BTH-treated leaves included receptor-like kinases SOBIR1, CERK1, and LYK5, which perceive pathogens, and EDS1, a regulator of the salicylic acid defense pathway. Other proteins that likely contributed to resistance included pathogenesis-related proteins, a full complement of enzymes that catalyze phenylpropanoid biosynthesis, and protein receptors, transporters, and enzymes that modulate other defense responses controlled by jasmonic acid, ethylene, brassinosteroid, abscisic acid, and auxin. Increases in the accumulation of proteins required for vesicle-mediated protein secretion and RNA splicing occurred as well. By contrast, more than half of the 168 decreases belonged to chloroplast proteins and proteins involved in cell expansion. These results reveal a set of proteins needed for rust resistance and reaffirm the utility of BTH to control disease by amplifying the natural immune system of the bean plant.


Assuntos
Resistência à Doença , Phaseolus , Proteoma , Tiadiazóis , Basidiomycota/fisiologia , Resistência à Doença/efeitos dos fármacos , Phaseolus/efeitos dos fármacos , Phaseolus/microbiologia , Proteoma/efeitos dos fármacos , Tiadiazóis/farmacologia
17.
Fish Shellfish Immunol ; 98: 324-333, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31981775

RESUMO

Microbial exopolysaccharides (EPS) from Lactococcus have been found to have an important role in the probiotic activity of this bacterium; however, the immunomodulatory and antioxidant activities have not been fully explored in aquaculture. In the present study, we investigated EPS-2 from Lactococcus lactis Z-2, isolated from healthy common carp, for its immunomodulatory and antioxidant effects and disease resistance against Aeromonas hydrophila in Cyprinus carpio L. We found that the molecular weight of EPS-2 was 18.65 KDa. The monosaccharide composition of this polymer was rhamnose, xylose, mannose, glucose, and galactose at a molar percentage of 13.3%, 14.1%, 18.5%, 27.4%, and 26.7%, respectively. EPS-2 treatment could modulate the immune responses in vitro and in vivo. In vitro tests showed that EPS-2 could significantly enhance the proliferation and phagocytosis activities (P < 0.05) as well as induce the production of nitic oxide (NO), pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6), and anti-inflammatory cytokines (IL-10, TGF-ß) (P < 0.05) in head kidney cells. When the fish were gavaged with three different concentrations of EPS-2 (250, 500, 1000 µg/mL) for 7 days and infected with A. hydrophila, different expression patterns of the NO, cytokines, lysozyme (LZM), and alkaline phosphatase (AKP) in the serum and of antioxidants (T-AOC, SOD, CAT, GSH, GSH-Px and MDA) in hepatopancreas were observed. Before infection with A. hydrophila, EPS-2 supplementation significantly up-regulated the NO production, protein levels of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6), LZM and AKP activities, and levels of antioxidant molecules compared to those in the negative (G1) group (P < 0.05), whereas levels of NO and pro-inflammatory cytokines and LZM and AKP activities were significantly lower than those in the positive (G2) group after infection (P < 0.05). However, whether infected or not, the expression levels of anti-inflammatory cytokines (IL-10, TGF-ß) were significantly increased in the EPS-2 treatment groups (P < 0.05). These results indicate that EPS-2 has immunomodulatory and antioxidant effects on common carp, both in vitro and/or in vivo, and can be applied as a common carp feed supplement to enhance fish immunity and disease resistance against A. hydrophila.


Assuntos
Aeromonas hydrophila/fisiologia , Antioxidantes/metabolismo , Carpas/imunologia , Resistência à Doença/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Lactococcus lactis/química , Polissacarídeos Bacterianos/farmacologia , Animais , Carpas/microbiologia , Proliferação de Células , Citocinas/metabolismo , Suplementos Nutricionais , Rim Cefálico/citologia , Rim Cefálico/efeitos dos fármacos , Rim Cefálico/imunologia , Óxidos de Nitrogênio/metabolismo , Fagocitose , Probióticos/farmacologia
18.
Aquat Toxicol ; 220: 105406, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31945653

RESUMO

Currently, feed adulteration and contamination with melamine (MEL) are considered one of the serious issues in the aquatic industry. With the limited studies of MEL exposure alone in fish, its adverse impacts on fish cannot be evaluated well. Accordingly, this study aimed to investigate the effects of MEL containing diets on the immune response, disease resistance to Aeromonas hydrophila, growth performance, chemical composition, immune-related genes expression, and histopathology of both spleen and head kidneys. Also, the efficacy of curcumin (CUR) dietary supplementation to alleviate MEL negative impacts were evaluated. A total of 180 apparently healthy Oreochromis niloticus (O. niloticus) were divided into four groups with three replicates fed the basal diet only, basal diet fortified with 200 mg/kg CUR, basal diet containing 1 % MEL, or a basal diet containing CUR + MEL. The results displayed that MEL significantly reduced growth performance indices and body crude lipid contents. Anemic, leukopenic, lymphocytopenic, heterocytopenic, esonipenic, hypoproteinemic and hypoalbuminic conditions were apparent. Moreover, depleted immune and antioxidant indicators including lysozyme activity, nitric oxide, immunoglobulin M, complement 3, glutathione peroxidase, and superoxide dismutase enzyme activity were recorded. Also, MEL reduced the disease resistance of O. niloticus to bacterial infection. Furthermore, MEL induced downregulation of mRNA levels of interleukin 1ß and tumor necrosis factor α in the spleen together with obvious pathological perturbations in both spleen and head kidneys. The CUR addition resulted in a significant enhancement in most indices. These results may conclude that MEL could alter both innate and adaptive immune responses via the negative transcriptional effect on immune-related genes together with the oxidative damage of the immune organs. Furthermore, CUR dietary supplements could be advantageous for mitigating MEL negative impacts, thus offering a favorable aquafeed additive for O. niloticus.


Assuntos
Ração Animal/análise , Ciclídeos , Curcumina/farmacologia , Citocinas/biossíntese , Resistência à Doença/efeitos dos fármacos , Contaminação de Alimentos/análise , Triazinas/toxicidade , Aeromonas hydrophila/crescimento & desenvolvimento , Animais , Antioxidantes/metabolismo , Ciclídeos/sangue , Ciclídeos/crescimento & desenvolvimento , Ciclídeos/metabolismo , Suplementos Nutricionais , Resistência à Doença/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Rim Cefálico/efeitos dos fármacos , Rim Cefálico/metabolismo , Estresse Oxidativo/efeitos dos fármacos
19.
Plant Physiol Biochem ; 147: 322-335, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31911359

RESUMO

It is well known that parasitic weeds such as Orobanche (broomrape) significantly decrease crop growth and yield. Although hormonal priming is a well-known inducer of plant resistance against broomrapes (Orobanche spp.), the metabolic events associated with such resistance are poorly understood. Therefore, the current work was undertaken to elucidate the role of SA in inducing tomato resistance against Orobanche, considering its impact on carbon and nitrogen metabolism of the host. Total carbon and nitrogen and levels of carbon (sugars, organic acids and fatty acids) and nitrogen (amino acids and polyamines)-containing metabolites as well as the activities of some key enzymes involved in their metabolic pathways were evaluated. Broomrape infection significantly disrupted C/N ratio in the host roots. On contrary, SA treatment markedly induced accumulation of sugars, organic acids, fatty acids, amino acids as well as polyamines in healthy plants. Under broomrape challenge, SA mitigated the infection-induced growth inhibition by improving the level of nitrogen-containing osmoprotectants (proline, arginine and some polyamines). However, a decrease was observed in some C and N assimilates which are well known to be potentially transferred to the parasite, such as sucrose, asparagine, alanine, serine and glutamate. Interestingly, SA treatment induced the catapolism of polyamines and fatty acids in the host root. Accordingly, our study suggests that SA-induced resistance against broomrape relies on the rational utilization of C and N assimilates in a manner that disturbs the sink strength of the parasite and/or activates the defense pool of the host.


Assuntos
Carbono , Resistência à Doença , Lycopersicon esculentum , Nitrogênio , Orobanche , Ácido Salicílico , Carbono/metabolismo , Resistência à Doença/efeitos dos fármacos , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/parasitologia , Nitrogênio/metabolismo , Orobanche/fisiologia , Ácido Salicílico/farmacologia
20.
Fish Shellfish Immunol ; 96: 254-261, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31839587

RESUMO

The dietary effects of a native medicinal plant from Iran, common mallow (Malvae sylvestris), was evaluated on growth performance, innate immune parameters, mucosal immune parameters, and resistance of rainbow trout (Oncorhynchus mykiss) against Yersinia ruckeri. Therefore, 360 fish (initial weight 10.42 ± 0.09 g) were randomly distributed into 12 fiberglass tanks. Experimental diets supplemented with 0 (as control- C), 1% (M1), 3% (M2) and 5% (M3) levels of M. sylvestris flowers extract were fed to the fish based on 3% of body weight for 8 weeks. At the terminal sampling, growth performance, liver and digestive enzymes activities, blood and mucosal immune responses were determined. Results showed that M2 and M3 had greater final weight, weight gain, SGR, survival rate and lower FCR; higher levels of total protein, albumin, globulin, and lower cortisol levels in comparison to control; 5% extract also lowered cholesterol and glucose levels as well as Lactate Dehydrogenase (LDH) activity. We reported higher values of hematocrit, hemoglobin, Mean Corpuscular Hemoglobin (MCH), Mean Corpuscular Volume (MCV), White Blood Cell (WBC), Red Blood Cell (RBC) and lymphocytes for treated groups. Innate immune responses (Alternative complement activity (ACH50) in M2 and M3 group, total Immunoglobulin (Ig) and lysozyme in M3), mucosal immune parameters (ACH50, total Ig for M2 and M3 group and lysozyme in all treated groups) were enhanced. Activities of digestive enzymes (protease in all treated groups, amylase for 3 and 5%, while lipase only for 5%) and lower activity of liver ALT enzyme in individuals treated with highest dose was observed. Overall results indicated that the extract can positively affect growth performance and immune responses of rainbow trout.


Assuntos
Resistência à Doença , Doenças dos Peixes/imunologia , Imunidade Inata , Malva/química , Oncorhynchus mykiss/imunologia , Extratos Vegetais/farmacologia , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Resistência à Doença/efeitos dos fármacos , Relação Dose-Resposta a Droga , Imunidade Inata/efeitos dos fármacos , Imunidade nas Mucosas/efeitos dos fármacos , Oncorhynchus mykiss/crescimento & desenvolvimento , Distribuição Aleatória , Yersiniose/imunologia , Yersiniose/veterinária , Yersinia ruckeri/fisiologia
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