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1.
Mol Biol Rep ; 48(1): 41-55, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33454908

RESUMO

Mosquito-transmitted diseases like zika, dengue, chikungunya, and yellow fever are known to affect human health worldwide. Numerous synthetic insecticides have been used as vector control for these diseases, but there is the challenge of environmental toxicity and vector resistance. This study investigated the medicinal and insecticidal potential of Lentinus squarrosulus against Aedes aegypti. The fruiting bodies were identified morphologically as well as using internal transcribed spacer (ITS) sequences for its molecular characterization. Genomic deoxyribonucleic acid (DNA) yield was confirmed with NanoDrop Spectrophotometer ND-1000 and amplified with ITSl and ITS4 primers. The amplicons were sequenced and the National Center for Biotechnology Information (NCBI) database identified the nucleotides. Its ethanol extract was subjected to phytochemical screening and gas chromatography mass spectrometry (GC-MS) analysis and tested against the pupa and fourth instar larva of Aedes aegypti with percentage mortality monitored. The Macrofungus was identified morphologically and confirmed with molecular characterization as Lentinus squarrosulus (LS). The gene sequence was deposited in GenBank (Accession number MK629662.1). GC-MS analysis showed that its ethanol extract has 25 bioactive compounds with 9,12-Octadecadienoic acid, ethyl ester having the highest percentage of 43.32% as well as methyl-2-oxo-1-pyrrolidine acetate and 17-octadecynoic acid having the lowest percentage (0.09%). The macrofungus contained varied concentrations of phytochemicals including phenols (159 mg/g GAE), tannins (1.6 mg/g TAE), and flavonoids (31.4 mg/g QE). The ethanol extract had significant potent effects on Aedes aegypti larva and pupa which could be due to the occurrence and abundance of 9,12-octadecadienoic acid in LS. The LC50 of the extract for larvicidal and pupicidal activities were 2.95 mg/mL and 3.55 mg/mL, respectively, while its LC90 were 6.31 mg/mL and 5.75 mg/mL respectively. Lentinus squarrosulus had insecticidal effects against the Aedes aegypti larva and pupa and possessed great potential as a source of alternative medicine and eco-friendly insecticides.


Assuntos
Aedes/efeitos dos fármacos , Lentinula/química , Extratos Vegetais/farmacologia , Viroses/prevenção & controle , Aedes/patogenicidade , Animais , Etanol/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Inseticidas/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Larva/patogenicidade , Mosquitos Vetores/efeitos dos fármacos , Mosquitos Vetores/patogenicidade , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Viroses/epidemiologia
2.
J Comp Pathol ; 172: 88-92, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31690421

RESUMO

A 7-month-old female mixed breed foal with a 2-day history of recumbency and inability to open its mouth convulsed acutely and died and was submitted for necropsy examination. The foal was thin and large patches of haemorrhage were present throughout the peritoneal wall, the diaphragmatic surfaces and the retroperitoneum. Numerous nematode larvae were visible on the serosal surfaces and penetrated and embedded into the subserosa associated with the haemorrhages. The dorsal portion of the abdominal diaphragm had a partial tear and large numbers of nematodes were within the muscle fibres. Histologically, the larvae had a smooth cuticle, polymyarian/coelomyarian musculature and multinucleated intestinal cells, and were typically surrounded by haemorrhage, neutrophils, dense fibrovascular connective tissue and rare multinucleated giant cells. Parasitological examination identified the larvae as Strongylus edentatus based on the morphology of the buccal capsule. Additionally, there was severe muscle necrosis of the tongue and liver tissue analysis detected selenium deficiency. S. edentatus infections are uncommon in California, USA, and are typically non-lethal. In this case, the selenium deficiency may have led to immunosuppression, resulting in the hyperinfection with S. edentatus, and to the muscle damage and tear of the diaphragm. Although ivermectin treatment was indicated in the history, inadequate deworming or anthelmintic resistance may have played a role in the severity of infection.


Assuntos
Doenças dos Cavalos/patologia , Doenças dos Cavalos/parasitologia , Infecções Equinas por Strongyloidea/patologia , Strongylus , Animais , Feminino , Cavalos , Larva/parasitologia , Larva/patogenicidade , Fígado/química , Músculos/parasitologia , Músculos/patologia , Peritônio/parasitologia , Peritônio/patologia , Selênio/análise , Strongylus/isolamento & purificação
3.
Plant Signal Behav ; 13(7): e1489668, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29947577

RESUMO

Tobacco hornworm (Manduca sexta, THW) is a voracious pest of tomato and potato. StZFP2 is a Q-type C2H2 zinc finger transcription factor (TF) that is induced upon wounding and infestation. Previous work has shown that Q-type C2H2 TFs are involved in stress responses and when over expressed, can enhance protection against drought, salinity or pathogen infection. Twelve transgenic lines (S1-S12) were tested that over-express StZFP2. Feeding S6 or S8 to THW significantly lowered larval weight (21-37%) as well as increased expression of StPIN2 in comparison to untransformed Kennebec. The increase in StPIN2, a classic marker for insect defense in potato, is consistent with the decreases in larval weight gain.


Assuntos
Manduca/patogenicidade , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/parasitologia , Solanum tuberosum/metabolismo , Solanum tuberosum/parasitologia , Animais , Larva/patogenicidade , Solanum lycopersicum/genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Solanum tuberosum/genética
4.
PLoS One ; 12(12): e0189803, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29244856

RESUMO

Gastrointestinal nematodes are a significant concern for animal health and well-being, and anthelmintic treatment is mainly performed through the use of chemical products. However, bioactive compounds produced by plants have shown promise for development as novel anthelmintics. The aim of this study is to assess the anthelmintic activity of protein fractions from Spigelia anthelmia on the gastrointestinal nematode Haemonchus contortus. Plant parts were separated into leaves, stems and roots, washed with distilled water, freeze-dried and ground into a fine powder. Protein extraction was performed with sodium phosphate buffer (75 mM, pH 7.0). The extract was fractionated using ammonium sulfate (0-90%) and extensively dialyzed. The resulting fractions were named LPF (leaf protein fraction), SPF (stem protein fraction) and RPF (root protein fraction), and the protein contents and activities of the fractions were analyzed. H. contortus egg hatching (EHA), larval exsheathment inhibition (LEIA) and larval migration inhibition (LMIA) assays were performed. Proteomic analysis was conducted, and high-performance liquid chromatography (HPLC) chromatographic profiles of the fractions were established to identify proteins and possible secondary metabolites. S. anthelmia fractions inhibited H. contortus egg hatching, with LPF having the most potent effects (EC50 0.17 mg mL-1). During LEIA, SPF presented greater efficiency than the other fractions (EC50 0.25 mg mL-1). According to LMIA, the fractions from roots, stems and leaves also reduced the number of larvae, with EC50 values of 0.11, 0.14 and 0.21 mg mL-1, respectively. Protein analysis indicated the presence of plant defense proteins in the S. anthelmia fractions, including protease, protease inhibitor, chitinase and others. Conversely, secondary metabolites were absent in the S. anthemia fractions. These results suggest that S. anthelmia proteins are promising for the control of the gastrointestinal nematode H. contortus.


Assuntos
Anti-Helmínticos/uso terapêutico , Hemoncose/tratamento farmacológico , Haemonchus/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Animais , Anti-Helmínticos/química , Cromatografia Líquida de Alta Pressão , Hemoncose/parasitologia , Hemoncose/veterinária , Haemonchus/patogenicidade , Larva/efeitos dos fármacos , Larva/patogenicidade , Loganiaceae/química , Extratos Vegetais/química , Folhas de Planta/química , Proteínas de Plantas/administração & dosagem , Proteínas de Plantas/química , Proteômica
5.
PLoS One ; 11(5): e0155682, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27214257

RESUMO

Ginkgo biloba is a typical relic plant that rarely suffers from pest hazards. This study analyzed the pattern of G. biloba pest hazards in Beijing; tested the antifeedant activity of G. biloba extracts, including ginkgo flavonoids, ginkgolide, and bilobalide, against Hyphantria cunea larvae; determined the activities of glutathione transferase (GSTs), acetylcholinesterase (AChE), carboxylesterase (CarE) and mixed-functional oxidase (MFO), in larvae after feeding on these G. biloba secondary metabolites; and screened for effective botanical antifeedants in the field. In this study, no indicators of insect infestation were found for any of the examined leaves of G. biloba; all tested secondary metabolites showed significant antifeedant activity and affected the activity of the four larval detoxifying enzymes. Ginkgolide had the highest antifeedant activity and the most significant effect on the detoxifying enzymes (P<0.05). Spraying leaves with G. biloba extracts or ginkgolide both significantly repelled H. cunea larvae in the field (P<0.05), although the former is more economical and practical. This study investigated the antifeedant activity of G. biloba secondary metabolites against H. cunea larvae, and the results provide new insights into the mechanism of G. biloba pest resistance. This study also developed new applications of G. biloba secondary metabolites for effective pest control.


Assuntos
Comportamento Alimentar/efeitos dos fármacos , Ginkgo biloba/química , Mariposas/efeitos dos fármacos , Controle Biológico de Vetores , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Pequim , Ginkgo biloba/metabolismo , Ginkgo biloba/parasitologia , Larva/efeitos dos fármacos , Larva/patogenicidade , Mariposas/crescimento & desenvolvimento , Mariposas/patogenicidade , Controle Biológico de Vetores/métodos , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle , Extratos Vegetais/metabolismo , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Metabolismo Secundário
6.
Parasitol Res ; 113(7): 2475-81, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24802866

RESUMO

Mosquitoes in the larval stage are attractive targets for pesticides because mosquitoes breed in water, and thus, it is easy to deal with them in this habitat. The use of conventional pesticides in the water sources, however, introduces many risks to people and/or the environment. Natural pesticides, especially those derived from plants, are more promising in this aspect. Aromatic plants and their essential oils are very important sources of many compounds that are used in different respects. Insecticides of botanical origin may serve as suitable alternative to chemical insecticides. Acetone, chloroform, ethyl acetate, methanol, and petroleum benzine leaf extracts of Clausena dentata were tested against the fourth instar larvae of Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti (Diptera: Culicidae). Larval mortality was observed after 24 h of exposure. The highest larval mortality was found in acetone leaf extract, C. quinquefasciatus (LC50 = 0.150278 mg/ml; LC90 = 7.302613 mg/ml), A. aegypti (LC50 = 0.169495 mg/ml; LC90 = 1.10034 mg/ml), and A. stephensi (LC50 = 0.045684 mg/ml; LC90 = 0.045684 mg/ml). GC-MS analysis of plant extracts of acetone solvent revealed 16 compounds, of which the major compounds were benzene,1,2,3-trimethoxy-5-(2-propenyl) (14.97%), Z,Z-6,28-heptatriactontadien-2-one (6.81%), 2-allyl-4-methylphenol (28.14%), 2-allyl-4-methylphenol (17.34%), and 2,6,10,14,18,22-tetracosahexaene, 2,6,10,15,19,23-hexamethyl (10.35%). Our result shows acetone leaf extracts of C. dentata have the potential to be used as an ideal eco-friendly approach for mosquito control.


Assuntos
Clausena/química , Insetos Vetores/crescimento & desenvolvimento , Inseticidas/química , Fenóis/química , Extratos Vegetais/química , Aedes/crescimento & desenvolvimento , Animais , Anopheles/crescimento & desenvolvimento , Culex/crescimento & desenvolvimento , Dengue/prevenção & controle , Filariose/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Concentração Inibidora 50 , Inseticidas/isolamento & purificação , Larva/crescimento & desenvolvimento , Larva/patogenicidade , Malária/prevenção & controle , Controle de Mosquitos , Fenóis/isolamento & purificação , Folhas de Planta/química
7.
Infect Immun ; 81(7): 2546-53, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23649095

RESUMO

Heligmosomoides bakeri is a nematode with parasitic development exclusively in the small intestine of infected mice that induces a potent STAT6-dependent Th2 immune response. We previously demonstrated that host protective expulsion of adult H. bakeri worms from a challenge infection was delayed in selenium (Se)-deficient mice. In order to explore mechanisms associated with the delayed expulsion, 3-week-old female BALB/c mice were placed on a torula yeast-based diet with or without 0.2 ppm Se, and after 5 weeks, they were inoculated with H. bakeri infective third-stage larvae (L3s). Two weeks after inoculation, the mice were treated with an anthelmintic and then rested, reinoculated with L3s, and evaluated at various times after reinoculation. Analysis of gene expression in parasite-induced cysts and surrounding tissue isolated from the intestine of infected mice showed that the local-tissue Th2 response was decreased in Se-deficient mice compared to that in Se-adequate mice. In addition, adult worms recovered from Se-deficient mice had higher ATP levels than worms from Se-adequate mice, indicating greater metabolic activity in the face of a suboptimal Se-dependent local immune response. Notably, the process of worm expulsion was restored within 2 to 4 days after feeding a Se-adequate diet to Se-deficient mice. Expulsion was associated with an increased local expression of Th2-associated genes in the small intestine, intestinal glutathione peroxidase activity, secreted Relm-ß protein, anti-H. bakeri IgG1 production, and reduced worm fecundity and ATP-dependent metabolic activity.


Assuntos
Heligmosomatoidea/imunologia , Imunidade Celular/efeitos dos fármacos , Selênio/deficiência , Infecções por Strongylida/imunologia , Trifosfato de Adenosina/metabolismo , Animais , Anti-Helmínticos/farmacologia , Ativação Enzimática , Feminino , Fertilidade , Regulação da Expressão Gênica/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Heligmosomatoidea/patogenicidade , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/imunologia , Larva/imunologia , Larva/patogenicidade , Camundongos , Camundongos Endogâmicos BALB C , Selênio/farmacologia , Infecções por Strongylida/parasitologia , Células Th2/citologia , Células Th2/imunologia , Fatores de Tempo
8.
Parasite Immunol ; 34(4): 199-209, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22394222

RESUMO

Withania somnifera is an ayurvedic Indian medicinal plant whose immunomodulatory activities have been widely used as a home remedy for several ailments. We recently observed immunostimulatory properties in the root extracts of chemotypes NMITLI-101, NMITLI-118, NMITLI-128 and pure withanolide, withaferin A. In the present study, we evaluated the potential immunoprophylactic efficacies of these extracts against an infective pathogen. Our results show that administration of aqueous ethanol extracts (10 mg/kg) and withaferin A (0·3 mg/kg), 7 days before and after challenge with human filarial parasite Brugia malayi, offers differential protection in Mastomys coucha with chemotype 101R offering best protection (53·57%) as compared to other chemotypes. Our findings also demonstrate that establishment of B. malayi larvae was adversely affected by pretreatment with withaferin A as evidenced by 63·6% reduction in adult worm establishment. Moreover, a large percentage of the established female worms (66·2%) also showed defective embryogenesis. While the filaria-specific immunological response induced by withaferin A and NMITLI-101 showed a mixed Th1/Th2 phenotype, 118R stimulated production of IFN-γ and 128R increased levels of IL-4. Taken together, our findings reveal potential immunoprophylactic properties of W. somnifera, and further studies are needed to ascertain the benefits of this plant against other pathogens as well.


Assuntos
Brugia Malayi/efeitos dos fármacos , Filariose Linfática/imunologia , Filariose Linfática/prevenção & controle , Murinae/parasitologia , Extratos Vegetais , Withania/química , Vitanolídeos , Animais , Brugia Malayi/crescimento & desenvolvimento , Brugia Malayi/patogenicidade , Citocinas/biossíntese , Filariose Linfática/parasitologia , Feminino , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/patogenicidade , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Plantas Medicinais/classificação , Doenças dos Roedores/imunologia , Doenças dos Roedores/parasitologia , Doenças dos Roedores/prevenção & controle , Células Th1/imunologia , Células Th2/imunologia , Resultado do Tratamento , Withania/classificação , Vitanolídeos/administração & dosagem , Vitanolídeos/farmacologia
9.
New Phytol ; 191(4): 1069-1082, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21592133

RESUMO

Induction studies focusing on target metabolites may not reveal metabolic changes occurring in plants after various challenges. By contrast, metabolic fingerprinting can be a powerful tool to find patterns that are either treatment-specific or general and was therefore used to depict plant responses after various challenges. Plants of Plantago lanceolata were challenged by mechanical damage, specialist herbivores (aphids or sawfly larvae), generalist herbivores (Lepidopteran caterpillars) or phytohormones (jasmonic or salicylic acid). After 3 d of treatment, local and systemic leaves were analyzed for characteristic target metabolites (iridoid glucosides and verbascoside) by gas chromatography coupled with mass spectrometry (GC-MS) and for metabolic fingerprints by liquid chromatography coupled with time of flight mass spectrometry (LC-TOF-MS). Whereas only marginal changes in target metabolite concentrations were found, metabolic fingerprints were substantially affected especially by generalist and phytohormone treatments. By contrast, mechanical damage and specialist herbivory caused fewer changes. Responses to generalists partly overlapped with the changes caused by jasmonic acid, but many additional peaks were up-regulated. Furthermore, many peaks were co-induced by jasmonic and salicylic acid. The surprisingly high co-induction of peaks by both phytohormones suggests that the signaling pathways regulate a set of common targets. Furthermore, only metabolic fingerprinting could reveal that herbivores induce additional species-specific pathways beyond these phytohormone responses.


Assuntos
Herbivoria , Metaboloma , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/metabolismo , Plantago/metabolismo , Animais , Afídeos/patogenicidade , Ciclopentanos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas/métodos , Glucosídeos/metabolismo , Glucosídeos Iridoides/metabolismo , Larva/patogenicidade , Oxilipinas/farmacologia , Fenóis/metabolismo , Folhas de Planta/parasitologia , Plantago/efeitos dos fármacos , Plantago/parasitologia , Transdução de Sinais , Estresse Mecânico
10.
Plant J ; 66(4): 591-602, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21284755

RESUMO

Aromatic L-amino acid decarboxylases (AADCs) are key enzymes operating at the interface between primary and secondary metabolism. The Arabidopsis thaliana genome contains two genes, At2g20340 and At4g28680, encoding pyridoxal 5'-phosphate-dependent AADCs with high homology to the recently identified Petunia hybrida phenylacetaldehyde synthase involved in floral scent production. The At4g28680 gene product was recently biochemically characterized as an L-tyrosine decarboxylase (AtTYDC), whereas the function of the other gene product remains unknown. The biochemical and functional characterization of the At2g20340 gene product revealed that it is an aromatic aldehyde synthase (AtAAS), which catalyzes the conversion of phenylalanine and 3,4-dihydroxy-L-phenylalanine to phenylacetaldehyde and dopaldehyde, respectively. AtAAS knock-down and transgenic AtAAS RNA interference (RNAi) lines show significant reduction in phenylacetaldehyde levels and an increase in phenylalanine, indicating that AtAAS is responsible for phenylacetaldehyde formation in planta. In A. thaliana ecotype Columbia (Col-0), AtAAS expression was highest in leaves, and was induced by methyl jasmonate treatment and wounding. Pieris rapae larvae feeding on Col-0 leaves resulted in increased phenylacetaldehyde emission, suggesting that the emitted aldehyde has a defensive activity against attacking herbivores. In the ecotypes Sei-0 and Di-G, which emit phenylacetaldehyde as a predominant flower volatile, the highest expression of AtAAS was found in flowers and RNAi AtAAS silencing led to a reduction of phenylacetaldehyde formation in this organ. In contrast to ecotype Col-0, no phenylacetaldehyde accumulation was observed in Sei-0 upon wounding, suggesting that AtAAS and subsequently phenylacetaldehyde contribute to pollinator attraction in this ecotype.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Folhas de Planta/metabolismo , Tirosina Descarboxilase/metabolismo , Acetaldeído/análogos & derivados , Acetaldeído/metabolismo , Acetatos/farmacologia , Animais , Arabidopsis/efeitos dos fármacos , Arabidopsis/parasitologia , Proteínas de Arabidopsis/genética , Descarboxilases de Aminoácido-L-Aromático/genética , Ciclopentanos/farmacologia , Comportamento Alimentar , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Insetos/patogenicidade , Larva/patogenicidade , Odorantes , Oxilipinas/farmacologia , Filogenia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/parasitologia , Pólen/genética , Pólen/metabolismo , Interferência de RNA , Homologia de Sequência de Aminoácidos , Tirosina Descarboxilase/genética , Compostos Orgânicos Voláteis/metabolismo , Volatilização
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