Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.922
Filtrar
1.
BMC Vet Res ; 20(1): 126, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561770

RESUMO

BACKGROUND: Ethno-veterinary practices could be used as a sustainable developmental tool by integrating traditional phytotherapy and husbandry. Phytotherapeutics are available and used worldwide. However, evidence of their antiparasitic efficacy is currently very limited. Parasitic diseases have a considerable effect on pig production, causing economic losses due to high morbidity and mortality. In this respect, especially smallholders and organic producers face severe challenges. Parasites, as disease causing agents, often outcompete other pathogens in such extensive production systems. A total of 720 faecal samples were collected in two farms from three age categories, i.e. weaners, fatteners, and sows. Flotation (Willis and McMaster method), modified Ziehl-Neelsen stained faecal smear, centrifugal sedimentation, modified Blagg technique, and faecal cultures were used to identify parasites and quantify the parasitic load. RESULTS: The examination confirmed the presence of infections with Eimeria spp., Cryptosporidium spp., Balantioides coli (syn. Balantidium coli), Ascaris suum, Oesophagostomum spp., Strongyloides ransomi, and Trichuris suis, distributed based on age category. A dose of 180 mg/kg bw/day of Allium sativum L. and 90 mg/kg bw/day of Artemisia absinthium L. powders, administered for 10 consecutive days, revealed a strong, taxonomy-based antiprotozoal and anthelmintic activity. CONCLUSIONS: The results highlighted the therapeutic potential of both A. sativum and A. absinthium against gastrointestinal parasites in pigs. Their therapeutic effectiveness may be attributed to the content in polyphenols, tocopherols, flavonoids, sterols, sesquiterpene lactones, and sulfoxide. Further research is required to establish the minimal effective dose of both plants against digestive parasites in pigs.


Assuntos
Anti-Infecciosos , Artemisia absinthium , Criptosporidiose , Cryptosporidium , Alho , Enteropatias Parasitárias , Parasitos , Doenças dos Suínos , Animais , Suínos , Feminino , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Fazendas , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/veterinária , Enteropatias Parasitárias/parasitologia , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/parasitologia , Fezes/parasitologia , Prevalência
2.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 36(1): 98-104, 2024 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-38604693

RESUMO

Parasitic diseases caused by protozoan and helminth infections are still widespread across the world, notably in tropical and subtropical areas, which threaten the children and adult health. Long-term use of anti-parasitic drugs may result in reduced drug susceptibility and even drug resistance. Antimicrobial peptides have been demonstrated to inhibit parasite growth and development, which has potential antiparasitic values. LL-37, the only human antimicrobial peptide in the cathelicidin family, has been widely investigated. This paper reviews the progress of researches on the antiparasitic activity of LL-37, and discusses the prospects of LL-37 in the research of parasites.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Catelicidinas , Criança , Humanos , Catelicidinas/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Peptídeos Antimicrobianos , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico
3.
Acta Trop ; 252: 107141, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342286

RESUMO

The impact of diet composition and energy content on schistosomiasis evolution and treatment efficacy is still controversial. This study compared the impact of sucrose-rich diet and intermittent fasting on Schistosoma mansoni infection and praziquantel (PZQ)-based chemotherapy response in mice. BALB/c mice were infected with S. mansoni and followed for 15 weeks. The animals were randomized into nine groups receiving high glycemic load (high-sucrose diet - HSD), low caloric load (standard chow alternate-day fasting - ADF), and standard chow ad libitum (AL). Eight weeks after S. mansoni infection, these groups remained untreated or were treated with PZQ (300 mg/kg/day) for 3 days. Our results indicated that parasite load (S. mansoni eggs and parasite DNA levels), granulomatous inflammation (granulomas number and size), and liver microstructural damage (reduction in hepatocytes number, increase in nucleus-cytoplasm ratio, connective stroma expansion and fibrosis) were increased in ADF-treated animals. These animals also showed decreased eggs retention, granulomatous inflammation and collagen accumulation in the small intestine. Conversely, HSD diet and PZQ treatment attenuated all these parameters and stimulated hepatic regenerative response. PZQ also stimulated fibrosis resolution in HSD-treated mice, effect that was limited ADF-exposed mice. Our findings indicate that dietary glycemic and energy load can modulate schistosomiasis progression and the severity of hepatic and intestinal granulomatous inflammation in untreated and PZQ-treated mice. Thus, lower intestinal eggs retention may potentially be linked to worsening liver disease in ADF, while attenuation of hepatic and intestinal granulomatous inflammation is consistent with reduced parasite load in HSD- and PZQ-treated animals.


Assuntos
Anti-Helmínticos , Hepatopatias , Esquistossomose mansoni , Esquistossomose , Animais , Camundongos , Schistosoma mansoni , Antiparasitários/uso terapêutico , Praziquantel/farmacologia , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/parasitologia , Fígado/parasitologia , Esquistossomose/tratamento farmacológico , Inflamação/tratamento farmacológico , Fibrose , Dieta , Sacarose/farmacologia , Sacarose/uso terapêutico , Anti-Helmínticos/uso terapêutico
4.
Prev Vet Med ; 224: 106134, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325114

RESUMO

The effective control of ectoparasitic salmon lice, Lepeophtheirus salmonis, in fish farms is challenged by the salmon lice having developed resistance towards several antiparasitic drugs and by the effectiveness of non-medicinal treatments being limited by considerations of fish welfare. When new antiparasitics are introduced to the market, these should be used sparingly to slow resistance development. Using a population model for salmon lice parameterised for salmonid fish farms in Norway, we quantified how reduced treatment effectiveness influences treatment frequency and lice abundance. Furthermore, we investigated when in the production cycle a highly effective lice treatment leads to the largest reduction in the total number of treatments, mean lice abundance and lice larvae production. Results showed that reductions in treatment effectiveness to lower than 50% led to the steepest increases in treatment frequency and mean lice abundance, as well as to increased risk that lice abundance increased beyond control. The timing of the most effective treatment had only moderate effects on the total treatment need and the mean number of adult female lice through the production cycle, but large effect on the production of lice larvae in spring. These findings imply that farmers can optimise the timing of the most effective treatment to reduce the release of lice larvae in the period of year when wild salmonids are in coastal waters, without compromising total treatment need or mean lice levels.


Assuntos
Copépodes , Doenças dos Peixes , Salmo salar , Salmonidae , Animais , Feminino , Pesqueiros , Antiparasitários/uso terapêutico , Larva , Doenças dos Peixes/tratamento farmacológico , Doenças dos Peixes/prevenção & controle , Doenças dos Peixes/epidemiologia , Salmão/parasitologia , Aquicultura/métodos
5.
Future Microbiol ; 19: 5-8, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38348569

RESUMO

Tweetable abstract There is an urgent need to consider antiparasitic drugs in global efforts to achieve and implement equitable and sustainable antimicrobial stewardship initiatives worldwide.


Assuntos
Anti-Infecciosos , Gestão de Antimicrobianos , Antiparasitários/uso terapêutico , Anti-Infecciosos/uso terapêutico , Antibacterianos/uso terapêutico
6.
Proc Natl Acad Sci U S A ; 121(9): e2312987121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38377214

RESUMO

Babesiosis is an emerging zoonosis and widely distributed veterinary infection caused by 100+ species of Babesia parasites. The diversity of Babesia parasites and the lack of specific drugs necessitate the discovery of broadly effective antibabesials. Here, we describe a comparative chemogenomics (CCG) pipeline for the identification of conserved targets. CCG relies on parallel in vitro evolution of resistance in independent populations of Babesia spp. (B. bovis and B. divergens). We identified a potent antibabesial, MMV019266, from the Malaria Box, and selected for resistance in two species of Babesia. After sequencing of multiple independently derived lines in the two species, we identified mutations in a membrane-bound metallodependent phosphatase (phoD). In both species, the mutations were found in the phoD-like phosphatase domain. Using reverse genetics, we validated that mutations in bdphoD confer resistance to MMV019266 in B. divergens. We have also demonstrated that BdPhoD localizes to the endomembrane system and partially with the apicoplast. Finally, conditional knockdown and constitutive overexpression of BdPhoD alter the sensitivity to MMV019266 in the parasite. Overexpression of BdPhoD results in increased sensitivity to the compound, while knockdown increases resistance, suggesting BdPhoD is a pro-susceptibility factor. Together, we have generated a robust pipeline for identification of resistance loci and identified BdPhoD as a resistance mechanism in Babesia species.


Assuntos
Anti-Infecciosos , Babesia , Babesiose , Humanos , Babesia/genética , Fosfatase Alcalina , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Babesiose/tratamento farmacológico , Babesiose/parasitologia , Genômica , Anti-Infecciosos/farmacologia
7.
Artigo em Inglês | MEDLINE | ID: mdl-38324876

RESUMO

Multiple myeloma (MM) associated with Chagas disease is rarely described. This disease and its therapy suppress T cell and macrophage functions and increase regulatory T cell function, allowing the increase of parasitemia and the risk of Chagas Disease Reactivation (CDR). We aimed to analyze the role of conventional (cPCR) and quantitative Polymerase Chain Reaction (qPCR) for prospective monitoring of T. cruzi parasitemia, searching for markers of preemptive antiparasitic therapy in MM patients with Chagas disease. Moreover, we investigated the incidence and management of hematological diseases and CDR both inside and outside the transplant setting in the MEDLINE database. We found 293 studies and included 31 of them. Around 1.9-2.0% of patients with Chagas disease were reported in patients undergoing Stem Cell Transplantation. One case of CDR was described in eight cases of MM and Chagas disease. We monitored nine MM and Chagas disease patients, seven under Autologous Stem Cell Transplantation (ASCT), during 44.56±32.10 months (mean±SD) using parasitological methods, cPCR, and qPCR. From these patients, three had parasitemia. In the first, up to 256 par Eq/mL were detected, starting from 28 months after ASCT. The second patient dropped out and died soon after the detection of 161.0 par Eq/mL. The third patient had a positive blood culture. Benznidazole induced fast negativity in two cases; followed by notably lower levels in one of them. Increased T. cruzi parasitemia was related to the severity of the underlying disease. We recommend parasitemia monitoring by qPCR for early introduction of preemptive antiparasitic therapy to avoid CDR.


Assuntos
Doença de Chagas , Transplante de Células-Tronco Hematopoéticas , Mieloma Múltiplo , Nitroimidazóis , Trypanosoma cruzi , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/complicações , Antiparasitários/uso terapêutico , Parasitemia/tratamento farmacológico , Parasitemia/epidemiologia , Parasitemia/parasitologia , Estudos Prospectivos , Transplante Autólogo , Doença de Chagas/tratamento farmacológico , Doença de Chagas/epidemiologia , Nitroimidazóis/uso terapêutico
8.
J Ethnopharmacol ; 326: 117858, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38346526

RESUMO

ETHNOPHARMACOLOGY RELEVANCE: The plant Typhonium trilobatum has been utilized in traditional medicine for the treatment of many ailments, including parasitic infections. Recent examinations indicate that the bioactive substances from this plant may have antiparasitic activities against Brugia malayi, which have not been determined. PURPOSE: The parasitic nematodes Brugia malayi, Brugia timori, and Wuchereria bancrofti causing lymphatic filariasis, remain a significant challenge to global public health. Given the ongoing nature of this enduring menace, the current research endeavours to examine the efficacy of an important medicinal plant, Typhonium trilobatum. METHODS: Different extracts of the T. trilobatum tubers were evaluated for their antiparasitic activity. The most prominent extract was subjected to Gas Chromatography Mass Spectrometry (GC-MS) and High Performance Liquid Chromatography (HPLC) followed by Column Chromatography for isolating bioactive molecules. The major compounds were isolated and characterized based on different spectroscopic techniques (FTIR, NMR and HRMS). Further, the antiparasitic activity of the isolated compounds was evaluated against B. malayi and compared with clinically used antifilarial drugs like Diethylcarbamazine and Ivermectin. RESULTS: The methanolic extract of the tuber exhibited significant antiparasitic activity compared to the other extracts. The bioactive molecules isolated from the crude extract were identified as Linoleic acid and Palmitic acid. Antiparasitic activity of both the compounds has been performed against B. malayi and compared with clinically used antifilarial drugs, Ivermectin and DEC. The IC50 value of Linoleic acid was found to be 6.09 ± 0.78 µg/ml after 24 h and 4.27 ± 0.63 µg/ml after 48 h, whereas for Palmitic acid the value was 12.35 ± 1.09 µg/ml after 24 h and 8.79 ± 0.94 µg/ml after 48 h. The IC50 values of both the molecules were found to be similar to the standard drug Ivermectin (IC50 value of 11.88 ± 1.07 µg/ml in 24 h and 2.74 ± 0.43 µg/ml in 48 h), and much better compared to the DEC (IC50 values of 194.2 ± 2.28 µg/ml in 24 h and 101.8 ± 2.06 µg/ml in 48 h). Furthermore, it has been observed that both the crude extracts and the isolated compounds do not exhibit any detrimental effects on the J774.A.1 macrophage cell line. CONCLUSION: The isolation and characterization of bioactive compounds present in the methanolic tuber extract of Typhonium trilobatum were explored. Moreover, the antimicrofilarial activity of the crude extracts and its two major compounds were determined using Brugia malayi microfilarial parasites without any significant side effects.


Assuntos
Brugia Malayi , Filariose , Plantas Medicinais , Animais , Humanos , Filariose/tratamento farmacológico , Filariose/parasitologia , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Ácido Palmítico , Ácido Linoleico/farmacologia , Extratos Vegetais/química , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico
9.
Parasitol Res ; 123(2): 141, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38393410

RESUMO

Subcutaneous dirofilariosis is a well-known disease caused mainly by Dirofilaria repens and described in several mammalian species including humans, dogs, and cats. Additionally, early developing stages of the heartworm Dirofilaria immitis are rarely reported in subcutaneous localization from humans and dogs. To our knowledge, confirmed clinical evidence of this condition has not been described in the cats yet, even if the feline hosts can be affected either by the classic adult-related heartworm form or heartworm-associated respiratory disease (HARD) caused by immature stages. A 2 year old, spayed male cat was presented for three subcutaneous nodules on the head and trunk. The cat lived in Northern Italy and was regularly vaccinated and treated monthly with an antiparasitic spot on formulation containing selamectin. One of the three nodules was surgically excised and examined. Histology showed the presence of a nodular lesion in the subcutis characterized by a severe inflammatory infiltrate composed of macrophages, small lymphocytes, with fewer eosinophils, and mast cells, supported by a proliferation of mature fibroblasts (fibrosis). Inflammatory cells were multifocally surrounding sections of parasites identified as adult nematodes. Microscopic features were compatible with D. immitis, which has been molecularly confirmed (98.2% identity to D. immitis isolate OP107739). The cat tested negative for D. immitis antigenemia and the two remaining nodules disappeared spontaneously in a few months. In region where heartworm is prevalent, aberrant localization of D. immitis should be considered in the differential diagnoses of subcutaneous filarial worms in cats and dogs.


Assuntos
Doenças do Gato , Dirofilaria immitis , Dirofilariose , Animais , Gatos , Masculino , Antiparasitários/uso terapêutico , Doenças do Gato/tratamento farmacológico , Dirofilariose/diagnóstico , Dirofilariose/tratamento farmacológico , Dirofilariose/parasitologia , Itália
10.
PLoS Negl Trop Dis ; 18(2): e0011956, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38359089

RESUMO

BACKGROUND: Chagas disease is caused by the protozoan parasite Trypanosoma cruzi and leads to ~10,000 deaths each year. Nifurtimox and benznidazole are the only two drugs available but have significant adverse effects and limited efficacy. New chemotherapeutic agents are urgently required. Here we identified inhibitors of the acidic M17 leucyl-aminopeptidase from T. cruzi (LAPTc) that show promise as novel starting points for Chagas disease drug discovery. METHODOLOGY/PRINCIPAL FINDINGS: A RapidFire-MS screen with a protease-focused compound library identified novel LAPTc inhibitors. Twenty-eight hits were progressed to the dose-response studies, from which 12 molecules inhibited LAPTc with IC50 < 34 µM. Of these, compound 4 was the most potent hit and mode of inhibition studies indicate that compound 4 is a competitive LAPTc inhibitor, with Ki 0.27 µM. Compound 4 is selective with respect to human LAP3, showing a selectivity index of >500. Compound 4 exhibited sub-micromolar activity against intracellular T. cruzi amastigotes, and while the selectivity-window against the host cells was narrow, no toxicity was observed for un-infected HepG2 cells. In silico modelling of the LAPTc-compound 4 interaction is consistent with the competitive mode of inhibition. Molecular dynamics simulations reproduce the experimental binding strength (-8.95 kcal/mol), and indicate a binding mode based mainly on hydrophobic interactions with active site residues without metal cation coordination. CONCLUSIONS/SIGNIFICANCE: Our data indicates that these new LAPTc inhibitors should be considered for further development as antiparasitic agents for the treatment of Chagas disease.


Assuntos
Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Humanos , Leucil Aminopeptidase/química , Leucil Aminopeptidase/farmacologia , Leucil Aminopeptidase/uso terapêutico , Doença de Chagas/tratamento farmacológico , Descoberta de Drogas , Antiparasitários/uso terapêutico , Tripanossomicidas/uso terapêutico
11.
PLoS Negl Trop Dis ; 18(2): e0011961, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38408095

RESUMO

BACKGROUND: Trypanosoma cruzi and HIV coinfection can evolve with depression of cellular immunity and increased parasitemia. We applied quantitative PCR (qPCR) as a marker for preemptive antiparasitic treatment to avoid fatal Chagas disease reactivation and analyzed the outcome of treated cases. METHODOLOGY: This mixed cross-sectional and longitudinal study included 171 Chagas disease patients, 60 coinfected with HIV. Of these 60 patients, ten showed Chagas disease reactivation, confirmed by parasites identified in the blood, cerebrospinal fluid, or tissues, 12 exhibited high parasitemia without reactivation, and 38 had low parasitemia and no reactivation. RESULTS: We showed, for the first time, the success of the timely introduction of benznidazole in the non-reactivated group with high levels of parasitemia detected by qPCR and the absence of parasites in reactivated cases with at least 58 days of benznidazole. All HIV+ patients with or without reactivation had a 4.0-5.1 higher chance of having parasitemia than HIV seronegative cases. A positive correlation was found between parasites and viral loads. Remarkably, treated T. cruzi/HIV-coinfected patients had 77.3% conversion from positive to negative parasitemia compared to 19.1% of untreated patients. Additionally, untreated patients showed ~13.6 times higher Odds Ratio of having positive parasitemia in the follow-up period compared with treated patients. Treated and untreated patients showed no differences regarding the evolution of Chagas disease. The main factors associated with all-cause mortality were higher parasitemia, lower CD4 counts/µL, higher viral load, and absence of antiretroviral therapy. CONCLUSION: We recommend qPCR prospective monitoring of T. cruzi parasitemia in HIV+ coinfected patients and point out the value of pre-emptive therapy for those with high parasitemia. In parallel, early antiretroviral therapy introduction is advisable, aiming at viral load control, immune response restoration, and increasing survival. We also suggest an early antiparasitic treatment for all coinfected patients, followed by effectiveness analysis alongside antiretroviral therapy.


Assuntos
Doença de Chagas , Coinfecção , Infecções por HIV , Nitroimidazóis , Trypanosoma cruzi , Humanos , Trypanosoma cruzi/genética , Parasitemia/tratamento farmacológico , Parasitemia/parasitologia , Estudos Longitudinais , Estudos Transversais , Estudos Prospectivos , Doença de Chagas/complicações , Doença de Chagas/tratamento farmacológico , Doença de Chagas/parasitologia , Nitroimidazóis/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Reação em Cadeia da Polimerase , Antiparasitários/uso terapêutico , Coinfecção/parasitologia
12.
Sci Total Environ ; 917: 170175, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38244617

RESUMO

Fipronil and imidacloprid have been widely detected in UK surface waters in recent years, often at concentrations that ecotoxicological studies have shown can harm aquatic life. Down-the-drain (DTD) passage of pet flea and tick treatments are being implicated as an important source, with many of the UK's 22 million cats and dogs receiving routine, year-round preventative doses containing these parasiticides. The UK Water Industry's 3rd Chemical Investigation Programme (UKWIR CIP3) has confirmed wastewater as a major entry pathway for these chemicals into surface waters, but the routes by which they enter the wastewater system remain unclear. We addressed this knowledge gap by conducting the first quantification of DTD emissions from 98 dogs treated with spot-on ectoparasiticides containing fipronil or imidacloprid, through bathing, bed washing and washing of owners' hands. Both chemicals were detected in 100 % of washoff samples, with bathing accounting for the largest emissions per event (up to 16.8 % of applied imidacloprid and 24.5 % of applied fipronil). Modelled to account for the frequency of emitting activities, owner handwashing was identified as the largest source of DTD emissions from the population overall, with handwash emissions occurring for at least 28 days following product application and an estimated 4.9 % of imidacloprid and 3.1 % of fipronil applied in dog spot-ons passing down-the-drain via this route. The normalised daily per capita emissions for all routes combined were 8.7 µg/person/day for imidacloprid and 2.1 µg/person/day for fipronil, equivalent to 20-40 % of the daily per capita load in wastewater, as estimated from UKWIR CIP3 data. Within the current international regulatory framework adhered to by the UK, the environmental exposure of veterinary medicines intended for use in small companion animals is assumed to be low, and DTD pathways are not considered. We recommend a systematic review of regulations and practices to address this overlooked pollution pathway.


Assuntos
Inseticidas , Neonicotinoides , Nitrocompostos , Pirazóis , Humanos , Animais , Cães , Gatos , Inseticidas/análise , Antiparasitários/uso terapêutico , Águas Residuárias
13.
J Helminthol ; 98: e3, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38167243

RESUMO

Schistosomiasis afflicts approximately 120 million individuals globally. The hepatic pathology that occurs due to egg-induced granuloma and fibrosis is commonly attributed to this condition. However, there is currently no efficacious treatment available for either of these conditions.Our study aimed to investigate the potential antifibrotic and antiparasitic properties of different doses of gallic acid (GA) in experimental schistosomiasis mansoni. In addition, we investigated the outcomes of co-administering it with the standard anti-schistosomiasis treatment, praziquantel (PZQ).In experiment I, Schistosoma mansoni-infected mice were administered GA at doses of 10, 20, or 40 mg/kg. Their effectiveness was evaluated through parasitological (worm and egg loads, granuloma number and diameter), pathological (fibrosis percentage and H-score of hepatic stellate cells (HSCs)), and functional (liver enzymes) tests. In experiment II, we investigated the optimal dosage that yielded the best outcomes. This dosage was administered in conjunction with PZQ and was evaluated regarding the parasitological, pathological, functional, and immunological (fibrosis-regulating cytokines) activities.Our findings indicate that the administration of 40 mg/kg GA exhibited the highest level of effectiveness in experiment I. In experiment II, it exhibited lower antiparasitic efficacy in comparison to PZQ. However, it surpassed PZQ in other tests. It showed enhanced outcomes when combined with PZQ.In conclusion, our findings reveal that GA only slightly increased the antischistosomal activity of PZQ. However, it was linked to decreased fibrosis, particularly when administrated with PZQ. Our pilot study identifies GA as a natural antifibrotic agent, which could be administered with PZQ to mitigate the development of fibrosis.


Assuntos
Anti-Helmínticos , Esquistossomose mansoni , Animais , Camundongos , Esquistossomose mansoni/parasitologia , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Ácido Gálico/farmacologia , Ácido Gálico/uso terapêutico , Projetos Piloto , Fígado/parasitologia , Praziquantel , Schistosoma mansoni , Fibrose , Granuloma/tratamento farmacológico , Granuloma/patologia
14.
Vet J ; 303: 106066, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244671

RESUMO

Gastrointestinal nematode (GIN) infections impact small ruminant health, welfare, and production across farming systems. Rising anthelmintic resistance and regulation of synthetic drug use in organic farming is driving research and development of sustainable alternatives for GIN control. One alternative is the feeding of plants that contain secondary metabolites (PSMs) e.g., proanthocyanidins (PA, syn. condensed tannins) that have shown anthelmintic potential. However, PSMs can potentially impair performance, arising from reduced palatability and thus intake, digestibility or even toxicity effects. In this study, we tested the trade-off between the antiparasitic and anti-nutritional effects of heather consumption by lambs. The impact of additional feeding of a nematophagous fungus (Duddingtonia flagrans) on larval development was also explored. Lambs infected with Teladorsagia circumcincta or uninfected controls, were offered ad libitum heather, or a control chopped hay for 22 days during the infection patent period. Eight days into the patent period, parasitised lambs were supplemented (or remained unsupplemented) with D. flagrans for a 5-day period. Performance and infection metrics were recorded, and polyphenol levels in the heather and control hay were measured to investigate their association with activity. The lambs consumed heather at approximately 20% of their dry matter intake, which was sufficient to exhibit significant anthelmintic effects via a reduction in total egg output (P = 0.007), compared to hay-fed lambs; the magnitude of the reduction over time in heather fed lambs was almost 10-fold compared to control lambs. Negative effects on production were shown, as heather-fed lambs weighed 6% less than hay-fed lambs (P < 0.001), even though dry matter intake (DMI) of heather increased over time. D. flagrans supplementation lowered larval recovery in the faeces of infected lambs by 31.8% (P = 0.003), although no interactions between feeding heather and D. flagrans were observed (P = 0.337). There was no significant correlation between PA, or other polyphenol subgroups in the diet and egg output, which suggests that any association between heather feeding and anthelmintic effect is not simply and directly attributable to the measured polyphenols. The level of heather intake in this study showed no antagonistic effects on D. flagrans, demonstrating the methods can be used in combination, but provide no additive effect on overall anthelmintic efficacies. In conclusion, heather feeding can assist to reduce egg outputs in infected sheep, but at 20% of DMI negative effects on lamb performance can be expected which may outweigh any antiparasitic benefits.


Assuntos
Anti-Helmínticos , Calluna , Gastroenteropatias , Nematoides , Infecções por Nematoides , Doenças dos Ovinos , Animais , Ovinos , Infecções por Nematoides/prevenção & controle , Infecções por Nematoides/veterinária , Infecções por Nematoides/parasitologia , Fezes/parasitologia , Gastroenteropatias/veterinária , Polifenóis/uso terapêutico , Anti-Helmínticos/farmacologia , Anti-Helmínticos/uso terapêutico , Antiparasitários/uso terapêutico , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/prevenção & controle , Doenças dos Ovinos/parasitologia , Contagem de Ovos de Parasitas/veterinária
15.
Microbiol Spectr ; 12(2): e0296823, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38206030

RESUMO

Auranofin, an FDA-approved drug for rheumatoid arthritis, has emerged as a promising antiparasitic medication in recent years. The gold(I) ion in auranofin is postulated to be responsible for its antiparasitic activity. Notably, aurothiomalate and aurothioglucose also contain gold(I), and, like auranofin, they were previously used to treat rheumatoid arthritis. Whether they have antiparasitic activity remains to be elucidated. Herein, we demonstrated that auranofin and similar derivatives, but not aurothiomalate and aurothioglucose, inhibited the growth of Toxoplasma gondii in vitro. We found that auranofin affected the T. gondii biological cycle (lytic cycle) by inhibiting T. gondii's invasion and triggering its egress from the host cell. However, auranofin could not prevent parasite replication once T. gondii resided within the host. Auranofin treatment induced apoptosis in T. gondii parasites, as demonstrated by its reduced size and elevated phosphatidylserine externalization (PS). Notably, the gold from auranofin enters the cytoplasm of T. gondii, as demonstrated by scanning transmission electron microscopy-energy dispersive X-ray spectroscopy (STEM-EDS) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS).IMPORTANCEToxoplasmosis, caused by Toxoplasma gondii, is a devastating disease affecting the brain and the eyes, frequently affecting immunocompromised individuals. Approximately 60 million people in the United States are already infected with T. gondii, representing a population at-risk of developing toxoplasmosis. Recent advances in treating cancer, autoimmune diseases, and organ transplants have contributed to this at-risk population's exponential growth. Paradoxically, treatments for toxoplasmosis have remained the same for more than 60 years, relying on medications well-known for their bone marrow toxicity and allergic reactions. Discovering new therapies is a priority, and repurposing FDA-approved drugs is an alternative approach to speed up drug discovery. Herein, we report the effect of auranofin, an FDA-approved drug, on the biological cycle of T. gondii and how both the phosphine ligand and the gold molecule determine the anti-parasitic activity of auranofin and other gold compounds. Our studies would contribute to the pipeline of candidate anti-T. gondii agents.


Assuntos
Artrite Reumatoide , Fosfinas , Toxoplasma , Toxoplasmose , Humanos , Auranofina/farmacologia , Auranofina/uso terapêutico , Ouro/farmacologia , Ouro/uso terapêutico , Ligantes , Aurotioglucose/farmacologia , Aurotioglucose/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Tiomalato Sódico de Ouro/farmacologia , Tiomalato Sódico de Ouro/uso terapêutico , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico
16.
Arch Microbiol ; 206(2): 78, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38277061

RESUMO

Varicellovirus bovinealpha 1 (formerly bovine alphaherpesvirus type 1, BoAHV-1) is associated with several syndromes in cattle, including respiratory disease and is one of the main agents involved in the bovine respiratory disease complex (BRDC). Its infectious cycle is characterized by latent infections with sporadic virus reactivation and transmission. Although the acute disease can be prevented by the use of vaccines, specific therapeutic measures are not available. Ivermectin (IVM) is a semi-synthetic avermectin with a broad-spectrum antiparasitic activity, which has previously shown to have potential as an antiviral drug. In this study, IVM antiviral activity against BoAHV-1 was characterized in two cell lines (MDBK [Madin Darby bovine kidney] and BT [bovine turbinate]), including the measurement of intracellular drug accumulation within virus-infected cells. IVM antiviral activity was assessed at three different drug concentrations (1.25, 2.5 and 5 µM) after incubation for 24, 48 and 72 h. Slight cytotoxicity was only observed with 5 µM IVM. Even the lowest IVM dose was able to induce a significant reduction in virus titers in both cell lines. These findings indicate that the antiviral effects of IVM were evident in our experimental model within the range of concentrations achievable through therapeutic in vivo administration. Consequently, additional in vivo trials are necessary to validate the potential utility of these results in effectively managing BoAHV-1 in infected cattle.


Assuntos
Ivermectina , Varicellovirus , Animais , Bovinos , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Antivirais/farmacologia
17.
Comp Immunol Microbiol Infect Dis ; 104: 102096, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38000324

RESUMO

Animal parasitic diseases not only have an economic impact, but also have serious social and public health impacts. Although antiparasitic drugs can treat these diseases, it seems difficult for users to comprehensively utilize the information, due to incomplete and difficult data collection. Thus, there is an urgent need to establish a comprehensive database, that includes parasitic diseases and related drugs. In this paper, we develop a knowledge database dedicated to collecting and analyzing animal parasitic diseases and related drugs, named Animal Parasitic Diseases and Drugs Database (APDDD). The current version of APDDD includes animal parasitic disease data of 8 major parasite classifications that cause common parasitic diseases and 96 subclass samples mined from many literature and authoritative books, as well as 182 antiparasitic drugs. Furthermore, we utilized APDDD data to add a knowledge graph representing the relationships between parasitic diseases, drugs, and the targeted gene of drugs acting on parasites. We hope that APDDD will become a good database for animal parasitic diseases and antiparasitic drugs research and that users can gain a more intuitive understanding of the relationships between parasitic diseases, drugs, and targeted genes through the knowledge graph.


Assuntos
Parasitos , Doenças Parasitárias em Animais , Doenças Parasitárias , Animais , Doenças Parasitárias em Animais/tratamento farmacológico , Doenças Parasitárias em Animais/epidemiologia , Doenças Parasitárias/tratamento farmacológico , Doenças Parasitárias/epidemiologia , Antiparasitários/uso terapêutico , Saúde Pública
18.
Curr Med Chem ; 31(15): 1955-1982, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37718524

RESUMO

Protozoan parasites represent a significant risk for public health worldwide, afflicting particularly people in more vulnerable categories and cause large morbidity and heavy economic impact. Traditional drugs are limited by their toxicity, low efficacy, route of administration, and cost, reflecting their low priority in global health management. Moreover, the drug resistance phenomenon threatens the positive therapy outcome. This scenario claims the need of addressing more adequate therapies. Among the diverse strategies implemented, the medicinal chemistry efforts have also focused their attention on the benzimidazole nucleus as a promising pharmacophore for the generation of new drug candidates. Hence, the present review provides a global insight into recent progress in benzimidazole-based derivatives drug discovery against important protozoan diseases, such as malaria, leishmaniasis and trypanosomiasis. The more relevant chemical features and structure-activity relationship studies of these molecules are discussed for the purpose of paving the way towards the development of more viable drugs for the treatment of these parasitic infections.


Assuntos
Antiprotozoários , Leishmaniose , Malária , Tripanossomíase , Humanos , Antiparasitários/uso terapêutico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Antiprotozoários/química , Malária/tratamento farmacológico , Tripanossomíase/tratamento farmacológico , Leishmaniose/tratamento farmacológico , Benzimidazóis/farmacologia , Benzimidazóis/uso terapêutico
19.
Curr Top Med Chem ; 24(2): 89-108, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37842892

RESUMO

Recent developments in the use of natural product-based molecules as antiparasitic agents for Malaria, leishmaniasis (LE), Chagas disease (CD), and Human African trypanosomiasis (HAT) are reviewed. The role of diverse plants in developing bioactive species is discussed in addition to analyzing the structural diversity of natural products as active agents and the diverse biological applications in CD, HAT, LE, and Malaria. This review focuses on medicinal chemistry, emphasizing the structural characteristics of natural molecules as bioactive agents against parasitic infections caused by Leishmania, Trypanosoma, and Plasmodium parasites.


Assuntos
Antiprotozoários , Produtos Biológicos , Doença de Chagas , Leishmaniose , Malária , Tripanossomíase Africana , Animais , Humanos , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Antiparasitários/química , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Antiprotozoários/química , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Produtos Biológicos/química , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/parasitologia , Tripanossomíase Africana/tratamento farmacológico , Leishmaniose/tratamento farmacológico , Doença de Chagas/tratamento farmacológico , Malária/tratamento farmacológico
20.
Nat Commun ; 14(1): 6415, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37828012

RESUMO

Long-acting injectable medications, such as atovaquone, offer the prospect of a "chemical vaccine" for malaria, combining drug efficacy with vaccine durability. However, selection and transmission of drug-resistant parasites is of concern. Laboratory studies have indicated that atovaquone resistance disadvantages parasites in mosquitoes, but lack of data on clinically relevant Plasmodium falciparum has hampered integration of these variable findings into drug development decisions. Here we generate atovaquone-resistant parasites that differ from wild type parent by only a Y268S mutation in cytochrome b, a modification associated with atovaquone treatment failure in humans. Relative to wild type, Y268S parasites evidence multiple defects, most marked in their development in mosquitoes, whether from Southeast Asia (Anopheles stephensi) or Africa (An. gambiae). Growth of asexual Y268S P. falciparum in human red cells is impaired, but parasite loss in the mosquito is progressive, from reduced gametocyte exflagellation, to smaller number and size of oocysts, and finally to absence of sporozoites. The Y268S mutant fails to transmit from mosquitoes to mice engrafted with human liver cells and erythrocytes. The severe-to-lethal fitness cost of clinically relevant atovaquone resistance to P. falciparum in the mosquito substantially lessens the likelihood of its transmission in the field.


Assuntos
Anopheles , Antimaláricos , Malária Falciparum , Malária , Parasitos , Vacinas , Humanos , Animais , Camundongos , Atovaquona/farmacologia , Atovaquona/uso terapêutico , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Malária/parasitologia , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/genética , Anopheles/parasitologia , Antiparasitários/uso terapêutico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...