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1.
Langmuir ; 40(37): 19689-19700, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39235286

RESUMO

Matrine (MT) is a kind of alkaloid extracted from Sophora and is a promising substitute for chemical nematicides and botanical pesticides. The present study utilized sodium alginate (SA), zeolite imidazole salt skeleton (ZIF), and MT as raw materials to prepare a pH-response-release nematicide through the electrostatic spray technique. Zinc metal-organic framework (ZIF-8) was initially synthesized, followed by the successful loading of MT. Subsequently, the electrostatic spray process was employed to encapsulate it in SA, resulting in the formation of MT/ZIF-8@SA microcapsules. The efficiency of encapsulation and drug loadings can reach 79.93 and 26.83%, respectively. Soybean cyst nematode (SCN) is one of the important pests that harm crops; acetic acid produced by plant roots and CO2 produced by root respiration causing a decrease in the pH of the surrounding environment, which is most attractive to the SCN when the pH is between 4.5 and 5.4. MT/ZIF-8@SA releases the loaded MT in response to acetic acid produced by roots and acidic oxides produced by root respiration. The rate of release was 37.67% higher at pH 5.25 compared with pH 8.60. The control efficiency can reach 89.08% under greenhouse conditions. The above results demonstrate that the prepared MT/ZIF-8@SA not only exhibited excellent efficacy but also demonstrated a pH-responsive release of the nematicide.


Assuntos
Alginatos , Alcaloides , Cápsulas , Glycine max , Matrinas , Quinolizinas , Eletricidade Estática , Alginatos/química , Alcaloides/química , Alcaloides/farmacologia , Animais , Concentração de Íons de Hidrogênio , Quinolizinas/química , Glycine max/química , Glycine max/parasitologia , Cápsulas/química , Estruturas Metalorgânicas/química , Estruturas Metalorgânicas/farmacologia , Antinematódeos/química , Antinematódeos/farmacologia , Nematoides/efeitos dos fármacos , Liberação Controlada de Fármacos , Ácido Glucurônico/química , Ácidos Hexurônicos/química
2.
PLoS Pathog ; 20(9): e1012475, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39235992

RESUMO

Drug-resistant parasitic nematodes pose a grave threat to plants, animals, and humans. An innovative paradigm for treating parasitic nematodes is emphasized in this opinion. This approach relies on repurposing methuosis (a death characterized by accumulation of large vacuoles) inducing anticancer drugs as anthelmintics. We review drugs/chemicals that have shown to kill nematodes or cancerous cells by inducing multiple vacuoles that eventually coalesce and rupture. This perspective additionally offers a succinct summary on Structure-Activity Relationship (SAR) of methuosis-inducing small molecules. This strategy holds promise for the development of broad-spectrum anthelmintics, shedding light on shared molecular mechanisms between cancer and nematodes in response to these inducers, thereby potentially transforming both therapeutic domains.


Assuntos
Anti-Helmínticos , Antineoplásicos , Reposicionamento de Medicamentos , Humanos , Animais , Anti-Helmínticos/farmacologia , Antineoplásicos/farmacologia , Nematoides/efeitos dos fármacos , Neoplasias/tratamento farmacológico
3.
Int J Mol Sci ; 25(17)2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39273159

RESUMO

Southern root-knot nematodes are among the most pernicious phytoparasites; they are responsible for substantial yield losses in agricultural crops worldwide. The limited availability of nematicides for the prevention and control of plant-parasitic nematodes necessitates the urgent development of novel nematicides. Natural products have always been a key source for the discovery of pesticides. Waltherione A, an alkaloid, exhibits potent nematocidal activity. In this study, we designed and synthesized a series of quinoline and quinolone derivatives from Waltherione A, leveraging a strategy of structural simplification. Bioassays have revealed that the quinoline derivatives exhibit better activity than quinolone derivatives in terms of both nematocidal and fungicidal activities. Notably, compound D1 demonstrated strong nematocidal activity, with a 72 h LC50 of 23.06 µg/mL, and it effectively controlled the infection of root-knot nematodes on cucumbers. The structure-activity relationship suggests that the quinoline moiety is essential for the nematocidal efficacy of Waltherione A. Additionally, compound D1 exhibited broad-spectrum fungicidal activity, with an EC50 of 2.98 µg/mL against Botrytis cinerea. At a concentration of 200 µg/mL, it significantly inhibited the occurrence of B. cinerea on tomato fruits, with an inhibitory effect of 96.65%, which is slightly better than the positive control (90.30%).


Assuntos
Antinematódeos , Antinematódeos/farmacologia , Antinematódeos/síntese química , Antinematódeos/química , Relação Estrutura-Atividade , Animais , Desenho de Fármacos , Doenças das Plantas/parasitologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Cucumis sativus/parasitologia , Cucumis sativus/microbiologia , Fungicidas Industriais/farmacologia , Fungicidas Industriais/síntese química , Fungicidas Industriais/química , Quinolinas/química , Quinolinas/farmacologia , Quinolinas/síntese química , Nematoides/efeitos dos fármacos , Tylenchoidea/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Quinolonas/farmacologia , Quinolonas/química , Quinolonas/síntese química , Estrutura Molecular
4.
Int J Mol Sci ; 25(16)2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39201243

RESUMO

MaltAtt-1 is an antimicrobial peptide isolated from Monochamus alternatus with nematocidal activity against pine wood nematode. In this study, a eukaryotic expression system based on Komagataella phaffii GS115 was established, and its secretory expression of MaltAtt-1 was realized. The basic properties and secondary and tertiary structures of the antimicrobial peptide MaltAtt-1 were identified by bioinformatics analysis. MaltAtt-1 is a hydrophilic stable protein, mainly composed of an α-helix (Hh), ß-folds (Ee), and irregular curls (Cc). The optimal fermentation conditions for MaltAtt-1 were determined by a single-factor test and the Box-Behnken response surface method, including an induction time of 72 h, induction temperature of 30 °C, culture medium of pH 7.6, methanol volume fraction of 2.0%, and an initial glycerol concentration of 1%. The stability of MaltAtt-1 indicated its resistant to UV irradiation and repeated freezing and thawing, but the antibacterial activity decreased significantly under the influence of high temperature and a strong acid and base, and it decreased significantly to 1.1 cm and 0.83 cm at pH 2.0 and pH 10.0, respectively. The corrected mortality of B. xylophilus achieved 71.94% in 3 h at a concentration of 300 mg·L-1 MaltAtt-1 exposure. The results provide a theoretical basis for the antimicrobial peptide MaltAtt-1 to become a new green and efficient nematicide.


Assuntos
Peptídeos Antimicrobianos , Animais , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Nematoides/efeitos dos fármacos , Pinus/parasitologia , Pinus/química , Saccharomycetales/metabolismo , Concentração de Íons de Hidrogênio , Fermentação , Estabilidade Proteica , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/farmacologia
5.
Parasitol Int ; 103: 102940, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39094680

RESUMO

The use of medicinal plants as a means of combating parasites is becoming increasingly popular due to general resistance to synthetic anthelmintics. Goats typically respond less well to anthelminthic treatments, which may increase their resistance to nematodes. For this purpose, the anthelmintic effect of Pelargonium quercetorum Agnew (P. quercetorum) extract was tested in an in vivo study against gastrointestinal parasites of goats. A total of 40 goats naturally infected with mixed gastrointestinal nematode species were divided into four groups: the first group was treated with albendazole (7.5 mg/kg), the second group received a single dose of closantel (7.5 mg/kg), the third group received plant extract (7.5 mg/kg), and the fourth group served as an untreated control. Fecal egg counts (FEC) were carried out on day 14, as well as day 0, which was prior to the first treatment dose. According to the results, maximum reduction in FEC percentage was observed in P. quercetorum treated group (63.41%). Furthermore, nematode parasites responded poorly to synthetic drugs, although there was a 4.72% and 45.54% decrease in FEC in the albendazole and closantel-treated groups, respectively. Although no significant difference was found between the treatment groups, the P. quercetorum treated group showed a significant reduction in fecal egg count after treatment. Based on findings, a P. quercetorum based anthelmintic could be a sustainable alternative to combat parasite infestation. Therefore, further studies are needed to determine the optimal dose rate and frequency of doses required for effective control of gastrointestinal parasites in goats.


Assuntos
Albendazol , Anti-Helmínticos , Fezes , Doenças das Cabras , Cabras , Nematoides , Infecções por Nematoides , Contagem de Ovos de Parasitas , Pelargonium , Extratos Vegetais , Animais , Doenças das Cabras/parasitologia , Doenças das Cabras/tratamento farmacológico , Contagem de Ovos de Parasitas/veterinária , Infecções por Nematoides/veterinária , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Infecções por Nematoides/prevenção & controle , Fezes/parasitologia , Anti-Helmínticos/uso terapêutico , Anti-Helmínticos/farmacologia , Anti-Helmínticos/administração & dosagem , Pelargonium/química , Nematoides/efeitos dos fármacos , Albendazol/uso terapêutico , Albendazol/farmacologia , Albendazol/administração & dosagem , Extratos Vegetais/farmacologia , Gastroenteropatias/parasitologia , Gastroenteropatias/veterinária , Gastroenteropatias/tratamento farmacológico , Salicilanilidas/farmacologia , Salicilanilidas/administração & dosagem , Enteropatias Parasitárias/veterinária , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/parasitologia
6.
Rev Bras Parasitol Vet ; 33(3): e010524, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39140497

RESUMO

This review outlines the current state of anthelmintic resistance (AHR) of gastrointestinal nematodes (GINs) among cattle in Argentina and Brazil, emphasizing the economic repercussions, animal health and welfare. The analysis explores factors associated with AHR and proposes a potential solution: the use of drug combinations. Both countries are grappling with a severe AHR scenario in cattle, having progressed through incipient, established, and advanced phases, leading to extreme cases of animal mortality due to ineffective control strategies. Genera such as Cooperia and Haemonchus have the highest reports of resistance, with Oesophagostomum radiatum also posing significant problems. While oral benzimidazoles and levamisole remain effective in most herds, moxidectin is entering an advanced resistance phase, and avermectins are increasingly deemed ineffective. The review explores the impact ofclimate, mixed grazing, animal movement and other husbandry practices, and the relationship between ectoparasite control and the emergence of resistant helminths. Notably, the discussion includes the strategic use of drug combinations as a valuable approach to address resistant GINs control in livestock, highlighting its significant potential to mitigate the challenges posed by AHR in the cattle industry of these countries.


Assuntos
Anti-Helmínticos , Doenças dos Bovinos , Resistência a Medicamentos , Nematoides , Infecções por Nematoides , Animais , Bovinos/parasitologia , Brasil , Argentina , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Infecções por Nematoides/veterinária , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Anti-Helmínticos/uso terapêutico , Nematoides/efeitos dos fármacos
7.
Vet Parasitol ; 331: 110253, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39032481

RESUMO

Gastrointestinal nematode (GIN) infection poses the most significant obstacle to the sustainable development of small ruminant (sheep and goat) farming globally. Resistance of GINs to synthetic anthelmintic drugs has led to rising interest in exploring alternative methods for parasite control, such as the utilization of bioactive plants with anti-parasitic properties. In this investigation, black seed (Nigella sativa), a shrub high in secondary antioxidant compounds, and sericea lespedeza (Lespedeza cuneata), a perennial legume high in tannins with anti-parasitic properties were combined to determine if two bioactive plants containing different types of secondary compounds can provide a stronger anti-parasitic effect than sericea lespedeza alone. In a 49-day trial, naturally parasitized 6-7-month-old intact male Spanish goats (n = 15/treatment) were fed pelletized feeds encompassing sericea lespedeza leaf meal (SL), a combination of black seed meal (BS) and sericea lespedeza leaf meal (BS-SL - 75 % SL, 25 % BS), or alfalfa (Medicago sativa, control parasitized; CONP), with an additional group of dewormed kids given the alfalfa pellets (Control treated; CONT). Weekly measurements of animal weights and samples of blood and feces were collected to determine the packed cell volume (PCV), GIN fecal egg counts (FEC), and coccidia fecal oocyte counts (FOC), respectively. All animals were processed at the end of the trial (60 total), with adult Haemonchus contortus worms recovered from the abomasum of each goat for counting and sex determination. Carcass weights were recorded after processing. Goats given the SL and BS-SL treatments had lower FEC (P<0.05) than the parasitized alfalfa (CONP) goats. At the end of the study, the SL and BS-SL groups' FOC values were lower (P < 0.05) than the CONT and CONP groups. A rise in PCV values was seen over time for all groups; SL, BS-SL, and CONT animals exhibited higher PCV values (P < 0.05) in comparison to the CONP goats. The parasitized goats fed SL-only pellets showed greater feed intake and animal body weights (P < 0.05) compared to goats fed BS-SL or alfalfa pellets. However, the treatments had no effect on the weight of the goats' carcasses. Although the H. contortus adult worm counts in the CONT goats (alfalfa-dewormed) were lower (P < 0.05) than in the CONP goats (alfalfa-parasitized), they did not differ from the SL or BS-SL animals. This study indicates that sericea lespedeza leaf meal pellet diet, either by itself or in combination with black seed meal, showed promising results as an anthelmintic and may prove to be an effective alternative to exclusive use of conventional deworming drugs. The addition of black seed did not appear to enhance the effectiveness of sericea lespedeza in this study.


Assuntos
Ração Animal , Doenças das Cabras , Cabras , Lespedeza , Infecções por Nematoides , Animais , Doenças das Cabras/parasitologia , Masculino , Ração Animal/análise , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Lespedeza/química , Coccidiose/veterinária , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Folhas de Planta/química , Gastroenteropatias/veterinária , Gastroenteropatias/parasitologia , Dieta/veterinária , Sementes/química , Nigella sativa/química , Nematoides/efeitos dos fármacos , Nematoides/fisiologia , Contagem de Ovos de Parasitas/veterinária , Fezes/parasitologia , Coccídios/efeitos dos fármacos , Coccídios/fisiologia , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Anti-Helmínticos/administração & dosagem
8.
Plant Sci ; 347: 112185, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38986912

RESUMO

The cyclic peptides, cyclotides, are identified mostly with 29-31-aa (amino acid residues) but rarely with ≥ 34-aa in plants. Viola philippica is a well-known medicinal plant but a rare metallophyte with cyclotides. A hypothesis was hence raised that the potential novel 34-aa cyclotide of Viola philippica would clearly broaden the structural and functional diversities of plant cyclotides. After homology-cloning the cyclotide precursor gene of VpCP5, a 34-aa cyclotide (viphi I) was identified to be larger than 22 other known cyclotides in V. philippica. It had a chimeric primary structure, due to its unusual loop structures (8 residues in loop 2 and 6 residues in loop 5) and aa composition (3 E and 5 R), by using phylogenetic analyses and an in-house cyclotide analysis tool, CyExcel_V1. A plasmid pCYC-viphi_I and a lab-used recombinant process were specially constructed for preparing viphi I. Typically, 0.12 or 0.25 mg ml-1 co-exposed viphi I could significantly remain cell activities with elevating Cd2+-exposed doses from 10-8 to 10-6 mol l-1 in MCF7 cells. In the model nematode Caenorhabditis elegans, IC50 values of viphi I to inhibit adult ratios and to induce death ratios, were 184.7 and 585.9 µg ml-1, respectively; the median lifespan of adult worms decreased from 14 to 2 d at viphi I doses ranging from 0.05 to 2 mg ml-1. Taken together, the newly identified viphi I exhibits functional potentials against cadmium and nematodes, providing new insights into structural and functional diversity of chimeric cyclotides in plants.


Assuntos
Cádmio , Ciclotídeos , Viola , Animais , Ciclotídeos/genética , Ciclotídeos/química , Viola/genética , Viola/metabolismo , Sequência de Aminoácidos , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Caenorhabditis elegans/genética , Caenorhabditis elegans/efeitos dos fármacos , Nematoides/efeitos dos fármacos , Nematoides/genética
9.
Nat Commun ; 15(1): 5529, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956039

RESUMO

Left unchecked, plant-parasitic nematodes have the potential to devastate crops globally. Highly effective but non-selective nematicides are justifiably being phased-out, leaving farmers with limited options for managing nematode infestation. Here, we report our discovery of a 1,3,4-oxadiazole thioether scaffold called Cyprocide that selectively kills nematodes including diverse species of plant-parasitic nematodes. Cyprocide is bioactivated into a lethal reactive electrophilic metabolite by specific nematode cytochrome P450 enzymes. Cyprocide fails to kill organisms beyond nematodes, suggesting that the targeted lethality of this pro-nematicide derives from P450 substrate selectivity. Our findings demonstrate that Cyprocide is a selective nematicidal scaffold with broad-spectrum activity that holds the potential to help safeguard our global food supply.


Assuntos
Antinematódeos , Sistema Enzimático do Citocromo P-450 , Nematoides , Animais , Sistema Enzimático do Citocromo P-450/metabolismo , Nematoides/efeitos dos fármacos , Antinematódeos/farmacologia , Sulfetos/farmacologia , Sulfetos/química
10.
Mar Pollut Bull ; 205: 116668, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38972217

RESUMO

Two concentrations (6.25 and 1.25 mg/L) were used for two Parkinson's disease medications, Benserazide, and Trihexyphenidyl, to test their effects on the meiobenthic nematofauna. It is predicted that these highly hydrosoluble drugs will end up in marine environments. The results showed that both medications when added alone, induced (i) important changes in the numbers and (ii) taxonomic composition. The impact of Benserazide and Trihexyphenidyl was also reflected in the (iii) functional traits of nematofauna, with the most affected categories following exposure being the trophic group 1B, the clavate tails, the circular amphids, the c-p2 life history, and the body length of 1-2 mm. These results were supported by the molecular interactions of the studied drugs with both GLD-3 and SDP proteins of Caenorhabditis elegans. (iv) The mixtures of both drugs did not show any changes in the nematode communities, suggesting that no synergistic or antagonistic interactions exist between them.


Assuntos
Antiparkinsonianos , Benserazida , Caenorhabditis elegans , Triexifenidil , Animais , Antiparkinsonianos/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/fisiologia , Poluentes Químicos da Água , Nematoides/efeitos dos fármacos
11.
PLoS One ; 19(6): e0301554, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38861496

RESUMO

In Sudan, resistance to benzimidazoles has been reported recently in cattle and goats from South Darfur. Herein, ivermectin efficacy against gastrointestinal nematodes (GINs) was evaluated in sheep and goats in three study areas in South Darfur. The faecal egg count reduction test (FECRT) was used to evaluate the efficacy of ivermectin in sheep and goats naturally infected with GINs in the region of Bulbul (goats: n = 106), Kass (goats: n = 40) and Nyala (Domaia (sheep: n = 47, goats: n = 77) and the University farm (goats: n = 52)), using different treatment plans, and the efficacy was evaluated 12 days after treatment. Ivermectin efficacy was also evaluated in goats experimentally infected using local Haemonchus contortus isolates from Kass and Nyala. Nematodes surviving ivermectin treatment in goats in Bulbul and Nyala were harvested and larvae used to infect worm-free male sheep (n = 6, ≤6 months old). Infected sheep were dosed subcutaneously with ivermectin every eight days with increasing doses from 0.2 mg/kg to 1.6 mg/kg bodyweight (bw). Reduced ivermectin efficacy was identified in sheep and goats in the four study locations. Using a paired statistic, the efficacy of a therapeutic dose in sheep was 75.6% (90% upper credible limit (UCrL): 77.5%), while twice the recommended dose led to a reduction of 92.6% (90% UCrL: 93.3%). In goats, the FECRs of a therapeutic dose were 72.9-95.3% (90% UCrL range: 73.6-95.7%) in Bulbul, Nyala Domaia, Nyala University farm and Kass. Twice the dose recommended for goats in Bulbul revealed a 90% UCrL of 87.6%. All post-treatment faecal cultures contained only Haemonchus spp. larvae. The experimental infection trials in sheep and goats supported our findings from field trials and calculated upper 90% CrL of below 98.9%. For the first time highly ivermectin resistant H. contortus populations have been identified in sheep and goats in Sudan, and resistance was experimentally confirmed.


Assuntos
Resistência a Medicamentos , Doenças das Cabras , Cabras , Ivermectina , Infecções por Nematoides , Doenças dos Ovinos , Animais , Cabras/parasitologia , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Ovinos/parasitologia , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/parasitologia , Doenças das Cabras/tratamento farmacológico , Doenças das Cabras/parasitologia , Sudão , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Fezes/parasitologia , Masculino , Contagem de Ovos de Parasitas/veterinária , Nematoides/efeitos dos fármacos , Anti-Helmínticos/uso terapêutico , Anti-Helmínticos/farmacologia , Haemonchus/efeitos dos fármacos
12.
Toxins (Basel) ; 16(6)2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38922168

RESUMO

Claviceptaceous endophytic fungi in the genus Epichloë mostly form a symbiotic relationship with cool-season grasses. Epichloë spp. are capable of producing bioactive alkaloids such as peramines, lolines, ergot alkaloids, and indole-diterpenes, which protect the host plant from herbivory by animals, insects, and nematodes. The host also benefits from enhanced tolerance to abiotic stresses, such as salt, drought, waterlogging, cold, heavy metals, and low nitrogen stress. The bioactive alkaloids produced can have both direct and indirect effects towards plant parasitic nematodes. Direct interaction with nematodes' motile stages can cause paralysis (nematostatic effect) or death (nematicidal effect). Indirectly, the metabolites may induce host immunity which inhibits feeding and subsequent nematode development. This review highlights the different mechanisms through which this interaction and the metabolites produced have been explored in the suppression of plant parasitic nematodes and also how the specific interactions between different grass genotypes and endophyte strains result in variable suppression of different nematode species. An understanding of the different grass-endophyte interactions and their successes and failures in suppressing various nematode species is essential to enable the proper selection of grass-endophyte combinations to identify the alkaloids produced, concentrations required, and determine which nematodes are sensitive to which specific alkaloids.


Assuntos
Alcaloides , Endófitos , Nematoides , Poaceae , Animais , Alcaloides/farmacologia , Endófitos/metabolismo , Poaceae/parasitologia , Nematoides/efeitos dos fármacos , Epichloe/metabolismo , Doenças das Plantas/parasitologia , Doenças das Plantas/microbiologia
13.
PLoS One ; 19(6): e0306390, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38935803

RESUMO

The economic impact of gastrointestinal (GI) nematode infections on livestock production is well documented worldwide. Increasing evidence supports the hypothesis that parasite colonization induces significant changes in the GI tract environment and, therefore, in the landscape where the microbiota and parasites occur. Understanding the interactions between bacterial and parasite populations in the digestive tract of livestock may be useful to design parasite control strategies based on microbiota modification. The aims of this work were to investigate the impact of the oxytetracycline-mediated manipulation of the gut microbial community on the composition of GI nematode populations in naturally infected sheep and to explore changes in the GI microbial communities after nematode population treatment with the anthelmintic compound monepantel. Extensive manipulation of the GI microbiota with a therapeutic dose of the long-acting oxytetracycline formulation did not induce significant changes in the GI nematode burden. The gut microbiota of treated animals returned to control levels 17 days after treatment, suggesting strong resilience of the sheep microbial community to antibiotic-mediated microbiota perturbation. A significant decrease of the bacterial Mycoplasmataceae family (Log2FC = -4, Padj = 0.001) and a marked increase of the Methanobacteriaceae family (Log2FC = 2.9, Padj = 0.018) were observed in the abomasum of sheep receiving the monepantel treatment. While a comprehensive evaluation of the interactions among GI mycoplasma, methanobacteria and nematode populations deserves further assessment, the bacteria-nematode population interactions should be included in future control programs in livestock production. Understanding how bacteria and parasites may influence each other in the GI tract environment may substantially contribute to the knowledge of the role of microbiota composition in nematode parasite establishment and the role of the parasites in the microbiota composition.


Assuntos
Microbioma Gastrointestinal , Trato Gastrointestinal , Nematoides , Infecções por Nematoides , Oxitetraciclina , Doenças dos Ovinos , Animais , Ovinos/parasitologia , Ovinos/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/microbiologia , Doenças dos Ovinos/tratamento farmacológico , Infecções por Nematoides/veterinária , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Infecções por Nematoides/microbiologia , Nematoides/microbiologia , Nematoides/efeitos dos fármacos , Nematoides/fisiologia , Oxitetraciclina/farmacologia , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/parasitologia , Aminoacetonitrila/análogos & derivados , Aminoacetonitrila/farmacologia , Bactérias/efeitos dos fármacos
14.
Int J Parasitol Drugs Drug Resist ; 25: 100547, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38733882

RESUMO

Anthelmintic resistance in sheep parasitic gastrointestinal nematodes is widespread and a severe health and economic issue but prevalence of resistance and involved parasite species are unknown in Germany. Here, the faecal egg count reduction test (FECRT) was performed on eight farms using fenbendazole, ivermectin and moxidectin and on four farms using only moxidectin. A questionnaire was used to obtain data on management practices to potentially identify risk factors for presence of resistance. All requirements of the recently revised WAAVP guideline for diagnosing anthelmintic resistance using the FECRT were applied. Nematode species composition in pre- and post-treatment samples was analysed with the nemabiome approach. Using the eggCounts statistic package, resistance against fenbendazole, ivermectin and moxidectin was found on 7/8, 8/8 and 8/12 farms, respectively. No formal risk factor analysis was conducted since resistance was present on most farms. Comparison with the bayescount R package results revealed substantial agreement between methods (Cohen's κ = 0.774). In contrast, interpretation of data comparing revised and original WAAVP guidelines resulted in moderate agreement (Cohen's κ = 0.444). The FECR for moxidectin was significantly higher than for ivermectin and fenbendazole. Nemabiome data identified 4 to 12 species in pre-treatment samples and treatments caused a small but significant decrease in species diversity (inverse Simpson index). Non-metric multidimensional scaling and k-means clustering were used to identify common patterns in pre- and post-treatment samples. However, post-treatment samples were scattered among the pre-treatment samples. Resistant parasite species differed between farms. In conclusion, the revised FECRT guideline allows robust detection of anthelmintic resistance. Resistance was widespread and involved multiple parasite species. Resistance against both drug classes on the same farm was common. Further studies including additional drugs (levamisole, monepantel, closantel) should combine sensitive FECRTs with nemabiome data to comprehensively characterise the anthelmintic susceptibility status of sheep nematodes in Germany.


Assuntos
Anti-Helmínticos , Fazendas , Fezes , Macrolídeos , Contagem de Ovos de Parasitas , Doenças dos Ovinos , Animais , Ovinos , Alemanha/epidemiologia , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/epidemiologia , Contagem de Ovos de Parasitas/métodos , Contagem de Ovos de Parasitas/veterinária , Fezes/parasitologia , Anti-Helmínticos/farmacologia , Macrolídeos/farmacologia , Ivermectina/farmacologia , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/tratamento farmacológico , Fenbendazol/farmacologia , Resistência a Medicamentos , Nematoides/efeitos dos fármacos , Nematoides/classificação , Nematoides/isolamento & purificação
15.
Chem Biodivers ; 21(8): e202401152, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38771298

RESUMO

A chemical investigation of a methanol extract derived from a solid-state rice culture of the nematode-cyst associated fungus Laburnicola nematophila K01 led to the isolation and characterization of a previously undescribed penillic acid analogue named laburnicolamine (1). The chemical structure was elucidated through comprehensive 1D and 2D NMR spectroscopic analyses in methanol-d4 and DMSO-d6, alongside with HR-ESI-MS spectrometry. The absolute configuration of 1 was concluded through the electronic circular dichroism (ECD) and time-dependent density functional theory-ECD (TDDFT-ECD) computations compared to its acquired spectrum. Biological assays revealed that compound 1 exhibited no significant cytotoxic, antimicrobial, or nematicidal activity.


Assuntos
Testes de Sensibilidade Microbiana , Animais , Humanos , Teoria da Densidade Funcional , Nematoides/efeitos dos fármacos , Conformação Molecular , Estrutura Molecular , Hypocreales/química
16.
Parasitol Res ; 123(5): 207, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713234

RESUMO

Biomarkers are specific molecular, histological, or physiological characteristics of normal or pathogenic biological processes and are promising in the diagnosis of gastrointestinal nematodes (GINs). Although some biomarkers have been validated for infection by Ostertagia sp. in cattle raised in temperate regions, there is a lack of information for tropical regions. The aim of this project was to assess potential biomarkers and validate the most promising. In the first study, 36 bovines (Nelore breed) naturally infected by GINs were distributed into two groups: infected (not treated with anthelmintic) and treated (treated with fenbendazole on days 0, 7, 14, 21, 28, 42, and 56). The variables of interest were live weight, fecal egg count, hemogram, serum biochemical markers, phosphorus, gastrin, and pepsinogen. In the second step, pepsinogen was assessed in cattle of the Nelore breed distributed among three groups: infected (not treated with anthelmintic), MOX (treated with moxidectin), and IVM + BZD (treated with ivermectin + albendazole). In the first study, no difference between groups was found for weight, albumin, hematocrit (corpuscular volume [CV]), erythrocytes, or hemoglobin. Negative correlations were found between pepsinogen and both CV and albumin, and albumin was negatively correlated with the percentage of Haemonchus sp. in the fecal culture. Among the biomarkers, only pepsinogen differentiated treated and infected (beginning with the 28th day of the study). In the second study, a reduction in pepsinogen was found after anthelmintic treatment. Therefore, pepsinogen is a promising biomarker of worms in cattle naturally infected by the genera Haemonchus and Cooperia in tropical areas.


Assuntos
Biomarcadores , Doenças dos Bovinos , Fezes , Infecções por Nematoides , Clima Tropical , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Doenças dos Bovinos/tratamento farmacológico , Biomarcadores/sangue , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Infecções por Nematoides/tratamento farmacológico , Fezes/parasitologia , Contagem de Ovos de Parasitas , Anti-Helmínticos/uso terapêutico , Nematoides/isolamento & purificação , Nematoides/classificação , Nematoides/efeitos dos fármacos , Gastroenteropatias/parasitologia , Gastroenteropatias/veterinária , Enteropatias Parasitárias/veterinária , Enteropatias Parasitárias/parasitologia , Fenbendazol/uso terapêutico
17.
J Dairy Res ; 91(1): 19-24, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38757385

RESUMO

The objective of this study was to determine the effect of dietary calcium soaps from garlic (Allium sativum) and willow (Salix babylonica) extracts on nematode loads, nutrient intake and digestibility, nitrogen balance and rumen fermentation kinetics in dairy goats. Nine adult non-lactating Saanen goats were grouped into a complete randomized block design with 3 treatments (n = 3) over a period of 28 d. Animals were fed a diet based on alfalfa hay and a concentrate that was supplemented (65 g/kg DM) with calcium soaps of safflower (control), garlic or willow. Intake of dry matter (DM), organic matter (OM) and neutral detergent fiber (NDF) were not affected by dietary calcium soaps. However, the highest digestibility of DM and OM were observed in willow supplemented goats. In vitro gas kinetics and fermentation profile were not affected by diets. Results from fecal egg count indicated a reduction in total count, Haemonchus spp. and Trychostrongylus spp. for both garlic and willow compared to control. Our results suggest that calcium soaps of garlic or willow extracts can be used to reduce gastrointestinal parasites in goats without compromising productive traits or rumen function.


Assuntos
Ração Animal , Dieta , Digestão , Fermentação , Alho , Cabras , Nitrogênio , Extratos Vegetais , Rúmen , Salix , Animais , Cabras/fisiologia , Alho/química , Salix/química , Rúmen/parasitologia , Rúmen/metabolismo , Digestão/efeitos dos fármacos , Nitrogênio/metabolismo , Feminino , Extratos Vegetais/farmacologia , Ração Animal/análise , Dieta/veterinária , Doenças das Cabras/parasitologia , Doenças das Cabras/prevenção & controle , Suplementos Nutricionais , Nematoides/efeitos dos fármacos , Nutrientes , Fezes/parasitologia , Fezes/química , Contagem de Ovos de Parasitas/veterinária , Fenômenos Fisiológicos da Nutrição Animal , Cálcio
18.
ACS Nano ; 18(21): 13781-13793, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38752333

RESUMO

Pine wood nematode (PWN) disease is a globally devastating forest disease caused by infestation with PWN, Bursaphelenchus xylophilus, which mainly occurs through the vector insect Japanese pine sawyer (JPS), Monochamus alternatus. PWN disease is notoriously difficult to manage effectively and is known as the "cancer of pine trees." In this study, dual enzyme-responsive nanopesticides (AVM@EC@Pectin) were prepared using nanocoating avermectin (AVM) after modification with natural polymers. The proposed treatment can respond to the cell wall-degrading enzymes secreted by PWNs and vector insects during pine tree infestation to intelligently release pesticides to cut off the transmission and infestation pathways and realize the integrated control of PWN disease. The LC50 value of AVM@EC@Pectin was 11.19 mg/L for PWN and 26.31 mg/L for JPS. The insecticidal activity of AVM@EC@Pectin was higher than that of the commercial emulsifiable concentrate (AVM-EC), and the photostability, adhesion, and target penetration were improved. The half-life (t1/2) of AVM@EC@Pectin was 133.7 min, which is approximately twice that of AVM-EC (68.2 min). Sprayed and injected applications showed that nanopesticides had superior bidirectional transportation, with five-times higher AVM contents detected in the roots relative to those of AVM-EC when sprayed at the top. The safety experiment showed that the proposed treatment had lower toxicity and higher safety for nontarget organisms in the application environment and human cells. This study presents a green, safe, and effective strategy for the integrated management of PWN disease.


Assuntos
Biomassa , Ivermectina , Pinus , Animais , Pinus/parasitologia , Pinus/química , Ivermectina/análogos & derivados , Ivermectina/farmacologia , Ivermectina/química , Ivermectina/metabolismo , Doenças das Plantas/parasitologia , Doenças das Plantas/prevenção & controle , Nematoides/efeitos dos fármacos , Inseticidas/farmacologia , Inseticidas/química , Nanopartículas/química , Humanos
19.
J Hazard Mater ; 472: 134474, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38696961

RESUMO

Body size is a key life-history trait of organisms, which has important ecological functions. However, the relationship between soil antibiotic resistance gene (ARG) distribution and organisms' body size has not been systematically reported so far. Herein, the impact of organic fertilizer on the soil ARGs and organisms (bacteria, fungi, and nematode) at the aggregate level was analyzed. The results showed that the smaller the soil aggregate size, the greater the abundance of ARGs, and the larger the body size of bacteria and nematodes. Further analysis revealed significant positive correlations of ARG abundance with the body sizes of bacteria, fungi, and nematodes, respectively. Additionally, the structural equation model demonstrated that changes in soil fertility mainly regulate the ARG abundance by affecting bacterial body size. The random forest model revealed that total phosphorus was the primary soil fertility factor influencing the body size of organisms. Therefore, these findings proposed that excessive application of phosphate fertilizers could increase the risk of soil ARG transmission by increasing the body size of soil organisms. This study highlights the significance of organisms' body size in determining the distribution of soil ARGs and proposes a new disadvantage of excessive fertilization from the perspective of ARGs.


Assuntos
Bactérias , Tamanho Corporal , Resistência Microbiana a Medicamentos , Fertilizantes , Fungos , Nematoides , Microbiologia do Solo , Solo , Tamanho Corporal/efeitos dos fármacos , Bactérias/genética , Bactérias/efeitos dos fármacos , Animais , Solo/química , Fungos/genética , Fungos/efeitos dos fármacos , Nematoides/efeitos dos fármacos , Nematoides/genética , Resistência Microbiana a Medicamentos/genética
20.
Animal ; 18(6): 101156, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38718708

RESUMO

Gastrointestinal nematodes (GINs) are a significant threat to the sustainability of global sheep production. Periparturient ewes play a key role in GIN epidemiology, with increased GIN faecal egg counts (FECs) in these ewes resulting in heavy pasture contamination that facilitates parasitic gastroenteritis in immunologically naïve lambs later during the grazing period. Traditionally, blanket anthelmintic treatment would suppress GIN egg outputs in these ewes and subsequent pasture contamination. However, farmers are now advised to implement targeted selective treatment (TST) to reduce anthelmintic use and subsequent anthelmintic resistance development, yet, there is currently limited evidence to determine optimal TST strategies in ewes. In this study, the characteristics of 226 ewes on seven Welsh farms were assessed postlambing to identify factors associated with their individual strongyle FECs using negative binomial mixed model analysis. Nemabiome analysis was conducted on 34 ewes across two study farms using the Oxford Nanopore MinIon platform with an aim of identifying factors associated with variations in ewe nemabiome composition within flocks. The best-fitted model of ewe FEC incorporated ewe body condition score, dag score, breed, and an interaction effect between ewe age and litter size as fixed factors. The addition of a mean FEC value for ewes of a specific litter size on each farm further improved model fit and reduced between-farm variance in the model. Nemabiome analysis revealed significant variation in within flock nemabiome diversity on individual farms, with significantly reduced nemabiome diversity recorded in ewes exhibiting dags and in twin-bearing ewes on respective farms, whilst T. circumcincta was present as a significantly higher proportion of the nemabiome in Suffolk ewes and twin bearing ewes (P < 0.05) in respective flocks. Our data demonstrate that commonly recorded ewe characteristics can be exploited to predict individual periparturient ewe FEC and subsequently may be used as a guide for TST strategies on sheep farms once specific TST thresholds are identified to deliver the optimal balance between minimal pasture contamination and maximal GIN refugia. This study is the first to utilise Oxford Nanopore MinIon sequencing to evaluate the nemabiome of sheep, and to molecularly assess the nemabiome of individual ruminants within a flock/herd, with results indicating that significant within flock variations in nemabiome composition which may have implications for TST and flock management strategies.


Assuntos
Fezes , Infecções por Nematoides , Contagem de Ovos de Parasitas , Doenças dos Ovinos , Animais , Ovinos , Doenças dos Ovinos/parasitologia , Doenças dos Ovinos/prevenção & controle , Feminino , Infecções por Nematoides/veterinária , Fezes/parasitologia , Contagem de Ovos de Parasitas/veterinária , Anti-Helmínticos/uso terapêutico , Nematoides/efeitos dos fármacos , Período Periparto , Criação de Animais Domésticos/métodos , Gravidez , País de Gales
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