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1.
Anal Methods ; 16(25): 4136-4142, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38860551

RESUMO

The ivermectin (IVM), as a broad-spectrum antiparasitic drug, was widely prescribed to treat COVID-19 during the pandemic, despite lacking proven efficacy in combating this disease. Therefore, it is important to establish affordable devices in laboratories with minimal infrastructure. The laser engraving technology has been revolutionary in sensor manufacturing, primarily attributed to the diversity of substrates that can be employed and the freedom it provides in creating sensor models. In this work, electrochemical sensors based on graphene were developed using the laser engraving technology for IVM sensing. Through, the studies that used the techniques of cyclic voltammetry and differential pulse voltammetry, following parameter optimization, for the laser-induced graphene electrode demonstrated a mass transport governed by adsorption of the species and exhibited a linear working range of 10-100 (µmol L-1), a limit of detection (LOD) of 1.6 × 10-6 (mol L-1), a limit of quantification (LOQ) of 4.8 × 10-6 (mol L-1), and a sensitivity of 0.139 (µA µmol L-1). The developed method was successfully applied to direct analysis of pharmaceutical tablets, tap water (recovery of 94%) and synthetic urine samples (recovery between 97% and 113%). These results demonstrate the feasibility of the method for routine analyses involving environmental samples.


Assuntos
Técnicas Eletroquímicas , Grafite , Ivermectina , Lasers , Ivermectina/análise , Ivermectina/química , Técnicas Eletroquímicas/métodos , Técnicas Eletroquímicas/instrumentação , Grafite/química , Humanos , Limite de Detecção , Antiparasitários/urina , Antiparasitários/análise , Antiparasitários/química , Eletrodos , COVID-19 , SARS-CoV-2
2.
Phytomedicine ; 128: 155414, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38503155

RESUMO

BACKGROUND: Chagas disease and leishmaniasis affect a significant portion of the Latin American population and still lack efficient treatments. In this context, natural products emerge as promising compounds for developing more effective therapies, aiming to mitigate side effects and drug resistance. Notably, species from the Amaryllidaceae family emerge as potential reservoirs of antiparasitic agents due to the presence of diverse biologically active alkaloids. PURPOSE: To assess the anti-Trypanosoma cruzi and anti-Leishmania infantum activity of five isolated alkaloids from Hippeastrum aulicum Herb. (Amaryllidaceae) against different life stages of the parasites using in silico and in vitro assays. Furthermore, molecular docking was employed to evaluate the interaction of the most active alkaloids. METHODS: Five natural isoquinoline alkaloids isolated in suitable quantities for in vitro testing underwent preliminary in silico analysis to predict their potential efficacy against Trypanosoma cruzi (amastigote and trypomastigote forms) and Leishmania infantum (amastigote and promastigote forms). The in vitro antiparasitic activity and mammalian cytotoxicity were investigated with a subsequent comparison of both analysis (in silico and in vitro) findings. Additionally, this study employed the molecular docking technique, utilizing cruzain (T. cruzi) and sterol 14α-demethylase (CYP51, L. infantum) as crucial biological targets for parasite survival, specifically focusing on compounds that exhibited promising activities against both parasites. RESULTS: Through computational techniques, it was identified that the alkaloids haemanthamine (1) and lycorine (8) were the most active against T. cruzi (amastigote and trypomastigote) and L. infantum (amastigote and promastigote), while also revealing unprecedented activity of alkaloid 7­methoxy-O-methyllycorenine (6). The in vitro analysis confirmed the in silico tests, in which compound 1 presented the best activities against the promastigote and amastigote forms of L. infantum with half-maximal inhibitory concentration (IC50) 0.6 µM and 1.78 µM, respectively. Compound 8 exhibited significant activity against the amastigote form of T. cruzi (IC50 7.70 µM), and compound 6 demonstrated activity against the trypomastigote forms of T. cruzi and amastigote of L. infantum, with IC50 values of 89.55 and 86.12 µM, respectively. Molecular docking analyses indicated that alkaloids 1 and 8 exhibited superior interaction energies compared to the inhibitors. CONCLUSION: The hitherto unreported potential of compound 6 against T. cruzi trypomastigotes and L. infantum amastigotes is now brought to the forefront. Furthermore, the acquired dataset signifies that the isolated alkaloids 1 and 8 from H. aulicum might serve as prototypes for subsequent structural refinements aimed at the exploration of novel leads against both T. cruzi and L. infantum parasites.


Assuntos
Alcaloides , Amaryllidaceae , Isoquinolinas , Leishmania infantum , Simulação de Acoplamento Molecular , Trypanosoma cruzi , Trypanosoma cruzi/efeitos dos fármacos , Leishmania infantum/efeitos dos fármacos , Amaryllidaceae/química , Alcaloides/farmacologia , Alcaloides/química , Alcaloides/isolamento & purificação , Isoquinolinas/farmacologia , Isoquinolinas/química , Isoquinolinas/isolamento & purificação , Animais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Humanos , Antiparasitários/farmacologia , Antiparasitários/química , Antiparasitários/isolamento & purificação , Antiprotozoários/farmacologia , Antiprotozoários/química , Antiprotozoários/isolamento & purificação
3.
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
4.
Eur J Med Chem ; 254: 115378, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37084599

RESUMO

A series of thirty 1,2,3-triazolylsterols, inspired by azasterols with proven antiparasitic activity, were prepared by a stereocontrolled synthesis. Ten of these compounds constitute chimeras/hybrids of 22,26-azasterol (AZA) and 1,2,3-triazolyl azasterols. The entire library was assayed against the kinetoplastid parasites Leishmania donovani, Trypanosoma cruzi, and Trypanosoma brucei, the causatives agents for visceral leishmaniasis, Chagas disease, and sleeping sickness, respectively. Most of the compounds were active at submicromolar/nanomolar concentrations with high selectivity index, when compared to their cytotoxicity against mammalian cells. Analysis of in silico physicochemical properties were conducted to rationalize the activities against the neglected tropical disease pathogens. The analogs with selective activity against L. donovani (E4, IC50 0.78 µM), T brucei (E1, IC50 0.12 µM) and T. cruzi (B1- IC50 0.33 µM), and the analogs with broad-spectrum antiparasitic activities against the three kinetoplastid parasites (B1 and B3), may be promising leads for further development as selective or broad-spectrum antiparasitic drugs.


Assuntos
Doença de Chagas , Parasitos , Trypanosoma cruzi , Tripanossomíase Africana , Animais , Esteróis/farmacologia , Esteróis/química , Tripanossomíase Africana/tratamento farmacológico , Antiparasitários/química , Doença de Chagas/tratamento farmacológico , Mamíferos
5.
Int J Pharm ; 639: 122965, 2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37084836

RESUMO

Ivermectin (IVM) is a potent antiparasitic widely used in human and veterinary medicine. However, the low oral bioavailability of IVM restricts its therapeutic potential in many parasitic infections, highlighting the need for novel formulation approaches. In this study, poly(ε-caprolactone) (PCL) nanocapsules containing IVM were successfully developed using the nanoprecipitation method. Pumpkin seed oil (PSO) was used as an oily core in the developed nanocapsules. Previously, PSO was chemically analyzed by headspace solid-phase microextraction coupled to gas chromatography/mass spectrometry (HS-SPME/GC-MS). The solubility of IVM in PSO was found to be 4266.5 ± 38.6 µg/mL. In addition, the partition coefficient of IVM in PSO/water presented a logP of 2.44. A number of nanocapsule batches were produced by factorial design resulting in an optimized formulation. Negatively charged nanocapsules measuring around 400 nm demonstrated unimodal size distribution, and presented regular spherical morphology under transmission electron microscopy. High encapsulation efficiency (98-100%) was determined by HPLC. IVM-loaded capsules were found to be stable in nanosuspensions at 4 °C and 25 °C, with no significant variations in particle size observed over a period of 150 days. Nanoencapsulated IVM (0.3 mM) presented reduced toxicity to J774 macrophages and L929 fibroblasts compared to free IVM. Moreover, IVM-loaded nanocapsules also demonstrated enhanced in vitro anthelmintic activity against Strongyloides venezuelensis in comparison to free IVM. Collectively, the present findings demonstrate the promising potential of PCL-PSO nanocapsules to improve the antiparasitic effects exerted by IVM.


Assuntos
Ivermectina , Nanocápsulas , Humanos , Ivermectina/farmacologia , Ivermectina/química , Antiparasitários/farmacologia , Antiparasitários/química , Nanocápsulas/química , Polímeros , Poliésteres/química
6.
Molecules ; 26(21)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34770960

RESUMO

In this study, the essential oil (EO) from Laurelia sempervirens was analyzed by GC/MS and safrole (1) was identified as the major metabolite 1, was subjected to direct reactions on the oxygenated groups in the aromatic ring and in the side chain, and eight compounds (4 to 12) were obtained by the process. EO and compounds 4-12 were subjected to biological assays on 24 strains of the genus Saprolegnia, specifically of the species 12 S. parasitica and 12 S. australis. EO showed a significant effect against Saprolegnia strains. Compound 6 presents the highest activity against two resistant strains, with minimum inhibitory concentration (MIC) and minimum oomyceticidal concentration (MOC) values of 25 to 100 and 75 to 125 µg/mL, respectively. The results show that compound 6 exhibited superior activities compared to the commercial controls bronopol and azoxystrobin used to combat these pathogens.


Assuntos
Antiparasitários/farmacologia , Magnoliopsida/química , Óleos Voláteis/farmacologia , Safrol/farmacologia , Saprolegnia/efeitos dos fármacos , Animais , Antiparasitários/química , Antiparasitários/isolamento & purificação , Peixes , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Testes de Sensibilidade Parasitária , Safrol/química
7.
Molecules ; 26(19)2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34641539

RESUMO

Usnic acid is the best-studied lichen metabolite, presenting several biological activities, such as antibacterial, immunostimulating, antiviral, antifungal, anti-inflammatory, and antiparasitic agents; despite these relevant properties, it is a hydrophobic and toxic molecule. In this context, scientific research has driven the development of innovative alternatives, considering usnic acid as a source of raw material in obtaining new molecules, allowing structural modifications (syntheses) from it. The purpose is to optimize biological activities and toxicity, with less concentration and/or response time. This work presents a literature review with an analogy of the hydrophobic molecule of usnic acid with its hydrophilic derivative of potassium usnate, emphasizing the elucidation and structural characteristics, biological activities, and toxicological aspects of both molecules, and the advantages of using the promising derivative hydrophilic in different in vitro and in vivo assays when compared to usnic acid.


Assuntos
Benzofuranos/química , Benzofuranos/farmacologia , Potássio/química , Analgésicos/química , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Antiparasitários/química , Antiparasitários/farmacologia , Benzofuranos/toxicidade , Interações Hidrofóbicas e Hidrofílicas , Líquens/metabolismo
8.
Chem Biodivers ; 18(9): e2100310, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34231306

RESUMO

Propolis is a bee product that has been used in medicine since ancient times. Although its anti-inflammatory, antioxidant, antimicrobial, antitumor, and immunomodulatory activities have been investigated, its anti-parasitic properties remain poorly explored, especially regarding helminths. This review surveys the results obtained with propolis around the world against human parasites. Regarding protozoa, studies carried out with the protozoa Trypanosoma spp. and Leishmania spp. have demonstrated promising results in vitro and in vivo. However, there are fewer studies for Plasmodium spp., the etiological agent of malaria and less so for helminths, particularly for Fasciola spp. and Schistosoma spp. Despite the favorable in vitro results with propolis, helminth assays need to be further investigated. However, propolis has shown itself to be an excellent natural product for parasitology, thus opening new paths and approaches in its activity against protozoa and helminths.


Assuntos
Antiparasitários/farmacologia , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Própole/química , Animais , Antiparasitários/química , Antiparasitários/isolamento & purificação , Brasil , Helmintos/efeitos dos fármacos , Leishmania/efeitos dos fármacos , Estrutura Molecular , Testes de Sensibilidade Parasitária , Fenóis/química , Fenóis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plasmodium/efeitos dos fármacos , Trypanosoma/efeitos dos fármacos
9.
Curr Top Med Chem ; 21(21): 1900-1921, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33655860

RESUMO

Trypanosomatidae family belongs to the Kinetoplastida order, which consists of obligatory parasites that affect plants and all classes of vertebrates, especially humans and insects. Among the heteroxenic parasites, Leishmania spp., Trypanosoma cruzi, and T. brucei are protozoa of most significant interest for medicinal chemistry, being etiological agents of Leishmaniasis, Chagas, and Sleep Sickness diseases, respectively. Currently, inefficient pharmacotherapy, especially in chronic phases and low selectivity towards parasite/host cells, justifies the need to discover new drugs to treat them effectively. Among other targets, the sterol 14α-demethylase (CYP51), an enzyme responsible for ergosterol's biosynthesis in Trypanosomatidae parasites, has received more attention in the development of new bioactive compounds. In this context, antifungal ravuconazole proved to be the most promising drug among this class against T. cruzi, being used in combined therapy with Bnz in clinic trials. Non-antifungal inhibitors, such as VFV and VNF, have shown promising results against T. cruzi and T.brucei, respectively, being tested in Bnz-combined therapies. Among the experimental studies involving azoles, compound (15) was found to be the most promising derivative, displaying an IC50 value of 0.002 µM against amastigotes from T. cruzi, in addition to being non-toxic and highly selective towards TcCYP51 (< 25 nM). Interestingly, imidazole analog (16) was active against infectious forms of these three parasites, demonstrating Ki values of 0.17, 0.02, and 0.36 nM for CYP51 from T. cruzi, T. brucei, and L. infantum. Finally, this review will address promising inhibitors targeting sterol 14α-demethylase (CYP51) from Trypanosomatidae parasites, highlighting SAR studies, interactions with this target, and recent contributions and advances in the field, as well.


Assuntos
Inibidores de 14-alfa Desmetilase/farmacologia , Antiparasitários/farmacologia , Esterol 14-Desmetilase/metabolismo , Trypanosomatina/efeitos dos fármacos , Trypanosomatina/enzimologia , Inibidores de 14-alfa Desmetilase/química , Animais , Antiparasitários/química , Química Farmacêutica , Infecções por Euglenozoa/tratamento farmacológico , Infecções por Euglenozoa/parasitologia , Humanos
10.
Mar Drugs ; 19(2)2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33673266

RESUMO

The global rise of infectious disease outbreaks and the progression of microbial resistance reinforce the importance of researching new biomolecules. Obtained from the hydrolysis of chitosan, chitooligosaccharides (COSs) have demonstrated several biological properties, including antimicrobial, and greater advantage over chitosan due to their higher solubility and lower viscosity. Despite the evidence of the biotechnological potential of COSs, their effects on trypanosomatids are still scarce. The objectives of this study were the enzymatic production, characterization, and in vitro evaluation of the cytotoxic, antibacterial, antifungal, and antiparasitic effects of COSs. NMR and mass spectrometry analyses indicated the presence of a mixture with 81% deacetylated COS and acetylated hexamers. COSs demonstrated no evidence of cytotoxicity upon 2 mg/mL. In addition, COSs showed interesting activity against bacteria and yeasts and a time-dependent parasitic inhibition. Scanning electron microscopy images indicated a parasite aggregation ability of COSs. Thus, the broad biological effect of COSs makes them a promising molecule for the biomedical industry.


Assuntos
Anti-Infecciosos/farmacologia , Antiparasitários/farmacologia , Quitina/análogos & derivados , Anti-Infecciosos/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antiparasitários/química , Quitina/química , Quitina/farmacocinética , Quitosana , Microscopia Eletrônica de Varredura , Oligossacarídeos , Fatores de Tempo
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