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1.
Arch Pharm (Weinheim) ; 357(3): e2300440, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38048546

RESUMO

Leishmaniasis is an emerging tropical infectious disease caused by a protozoan parasite of the genus Leishmania. In this work, the molecular hybridization between a trimethoxy chalcone and a sulfonamide group was used to generate a series of sulfonamide-chalcones. A series of eight sulfonamide-chalcone hybrids were made with good yields (up to 95%). These sulfonamide-chalcones were tested against promastigotes of Leishmania amazonensis and cytotoxicity against mouse macrophages, which showed good antileishmanial activity with IC50 = 1.72-3.19 µM. Three of them (10c, 10g, and 10h) were also highly active against intracellular amastigotes and had a good selectivity index (SI > 9). Thus, those three compounds were docked in the cytosolic tryparedoxin peroxidase (cTXNPx) enzyme of the parasite, and molecular dynamics simulations were carried out. This enzyme was selected as a target protein for the sulfonamide-chalcones due to the fact of the anterior report, which identified a strong and stable interaction between the chalcone NAT22 (6) and the cTXNPx. In addition, a prediction of the drug-likeness, and the pharmacokinetic profile of all compounds were made, demonstrating a good profile of those chalcones.


Assuntos
Antiprotozoários , Chalcona , Chalconas , Animais , Camundongos , Chalconas/farmacologia , Chalcona/farmacologia , Relação Estrutura-Atividade , Antiprotozoários/farmacologia , Sulfanilamida , Sulfonamidas/farmacologia
2.
Exp Parasitol ; 238: 108269, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35526574

RESUMO

Leishmaniasis is a group of neglected vector-borne tropical diseases caused by protozoan parasites of the genus Leishmania that multiply within phagocytic cells and have a wide range of clinical manifestations. Cutaneous leishmaniasis (CL) is a serious public health that affects more than 98 countries, putting 350 million people at risk. There are no vaccines that have been proven to prevent CL, and the treatment relies on drugs that often have severe side effects, justifying the search for new antileishmanial treatments. In the present investigation, it is demonstrated that 4-(3-(4-allyl-2-methoxyphenoxy)propyl)-1-(4-methylbenzyl)-1H-1,2,3-triazole (7k) presents significant antileishmanial activity (IC50 of 7.4 µmol L-1 and 1.6 µmol L-1 for promastigote and amastigote forms, respectively), low cytotoxicity against macrophage cells (IC50 of 211.9 µmol L-1), and a selective index of 132.5. Under similar conditions, compound 7k outperformed glucantime and pentamidine, two commonly used drugs in clinics. In vivo assays on CL-infected female BALB/c mice demonstrated that compound 7k had activity similar to intralesional glucantime when administered orally, with decreased lesion and parasitic load, and a low systemic toxic effect. Given the importance of understanding the relationship between compound structure and biological activity in the research and development of new drugs, the development of a quantitative structure-activity relationship (QSAR) model for the leishmanicidal activity presented by the eugenol derivatives with 1,2,3-triazole functionalities is also described herein. This study demonstrates the therapeutic potential of orally active eugenol derivatives against CL and provides useful insights into the relationship between the chemical structures of triazolic eugenol derivatives and their biological profile.


Assuntos
Antiprotozoários , Leishmaniose Cutânea , Leishmaniose , Animais , Antiprotozoários/uso terapêutico , Antiprotozoários/toxicidade , Eugenol/farmacologia , Eugenol/uso terapêutico , Feminino , Humanos , Leishmaniose/tratamento farmacológico , Leishmaniose Cutânea/tratamento farmacológico , Antimoniato de Meglumina/uso terapêutico , Camundongos , Relação Quantitativa Estrutura-Atividade , Relação Estrutura-Atividade , Triazóis/farmacologia , Triazóis/uso terapêutico
3.
Parasitology ; 147(9): 1032-1037, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32364107

RESUMO

Cutaneous leishmaniasis (CL) is a major health problem in many countries and its current treatment involves multiple parenteral injections with toxic drugs and requires intensive health services. Previously, the efficacy of a single subcutaneous injection with a slow-release formulation consisting of poly(lactide-co-glycolide) (PLGA) microparticles loaded with an antileishmanial 3-nitro-2-hydroxy-4,6-dimethoxychalcone (CH8) was demonstrated in mice model. In the search for more easily synthesized active chalcone derivatives, and improved microparticle loading, CH8 analogues were synthesized and tested for antileishmanial activity in vitro and in vivo. The 3-nitro-2',4',6'-trimethoxychalcone (NAT22) analogue was chosen for its higher selectivity against intracellular amastigotes (selectivity index = 1489, as compared with 317 for CH8) and more efficient synthesis (89% yield, as compared with 18% for CH8). NAT22 was loaded into PLGA / polyvinylpyrrolidone (PVP) polymeric blend microspheres (NAT22-PLGAk) with average diameter of 1.9 µm. Although NAT22-PLGAk showed similar activity to free NAT22 in killing intracellular parasites in vitro (IC50 ~ 0.2 µm), in vivo studies in Leishmania amazonensis - infected mice demonstrated the significant superior efficacy of NAT22-PLGAk to reduce the parasite load. A single intralesional injection with NAT22-PLGAk was more effective than eight injections with free NAT22. Together, these results show that NAT22-PLGAk is a promising alternative for single-dose localized treatment of CL.


Assuntos
Antiprotozoários/uso terapêutico , Chalconas/uso terapêutico , Leishmania mexicana/efeitos dos fármacos , Leishmaniose Cutânea/prevenção & controle , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C
4.
Parasitology ; 147(14): 1792-1800, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32958098

RESUMO

Vitamin D has been reported to activate macrophage microbicidal mechanisms by inducing the production of antimicrobial peptides and nitric oxide (NO), but conversely has been shown to contribute to a greater susceptibility to Leishmania amazonensis infection in mice. Thus, this study aimed to evaluate the role of vitamin D during intracellular infection with L. amazonensis by examining its effect on macrophage oxidative mechanisms and parasite survival in vitro. Vitamins D2 and D3 significantly inhibited promastigote and amastigote growth in vitro. Vitamin D3 was not able to induce NO and reactive oxygen species (ROS) production in uninfected macrophages or macrophages infected with L. amazonensis. In addition, vitamin D3 in combination with interferon (IFN)-γ did not enhance amastigote killing and in fact, significantly reduced NO and ROS production when compared with the effect of IFN-γ alone. In this study, we demonstrated that vitamin D directly reduces parasite growth in infected macrophages (approximately 50-60% at 50 µm) but this effect is independent of the activation of macrophage oxidative mechanisms. These findings will contribute to a better understanding of the role of vitamin D in cutaneous leishmaniasis.


Assuntos
Antiparasitários/farmacologia , Colecalciferol/farmacologia , Ergocalciferóis/farmacologia , Leishmania mexicana/efeitos dos fármacos , Vitaminas/farmacologia , Leishmaniose Cutânea/metabolismo , Leishmaniose Cutânea/parasitologia , Macrófagos/metabolismo , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo
5.
Exp Parasitol ; 210: 107847, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32004535

RESUMO

Leishmaniasis is an infectious disease that has high endemicity and is among the six parasitic diseases of higher occurrence in the world. The current treatments are limited due to their toxicity, treatment resistance and high cost which have increased the search for new substances of natural origin for its therapy. Based on this, an in vitro biological and chemical investigation was carried out to evaluate the potential of Piper marginatum against Leishmania amazonesis. P. marginatum leaves were collected to obtain the essential oil (EO) and the ethanolic extract (CE). The chemical profile of the CE and fractions was obtained by 1H NMR. The analysis of the EO chemical composition was performed by GC-MS. EO, CE and fractions were submitted to antileishmanial and cytotoxicity assays against macrophages. The chromatographic profiles of EO, CE and fractions showed the presence of phenolic compounds and terpenoids, having 3,4-Methylenedioxypropiophenone as a major compound. All P. marginatum samples showed low toxicity to macrophages. The CE and the methanolic, hexane and ethyl acetate fractions had low cytotoxicity when compared to Pentamidine. All tested samples inhibited growth of L. amazonensis promastigotes. The antileishmanial activity of EO, CE and fractions were evaluated in macrophages infected with L. (L.) amazonensis and treated with the concentrations 1, 10 and 100 µg/mL for 48 h. All samples were active, but EO and CE showed superior activity against amastigote forms when compared to the promastigote forms of L. amazonensis. This work describes for the first time the antileishmanial activity of the species P. marginatum and its cytotoxicity against macrophages, suggesting that it can be an alternative source of natural products in the phytotherapeutic treatment of leishmaniasis.


Assuntos
Leishmania mexicana/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Óleos Voláteis/farmacologia , Piper/química , Extratos Vegetais/farmacologia , Animais , Brasil/epidemiologia , Doenças Endêmicas , Cromatografia Gasosa-Espectrometria de Massas , Concentração Inibidora 50 , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Espectroscopia de Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/parasitologia , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Óleos de Plantas/farmacologia
6.
Nanomedicine ; 24: 102121, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31672601

RESUMO

Cutaneous leishmaniasis (CL) is a neglected parasitic disease conventionally treated by multiple injections with systemically toxic drugs. Aiming at a more acceptable therapy, we developed lipid-core nanocapsules (LNCs) entrapping the potent antileishmanial chalcone (CH8) for topical application. Rhodamine-labeled LNC (Rho-LNC-CH8) was produced for imaging studies. LNC-CH8 and Rho-LNC-CH8 had narrow size distributions (polydispersity index <0.10), with similar mean sizes (~180 nm) by dynamic light scattering. In vitro, Rho-LNC-CH8 was rapidly internalized by extracellular Leishmania amazonensis parasites macrophages in less than 15 min. LNC-CH8 activated macrophage oxidative mechanisms more efficiently than CH8, and was more selectively toxic against the intracellular parasites. In vivo, topically applied Rho-LNC-CH8 efficiently permeated mouse skin. In L. amazonensis-infected mice, LNC-CH8 reduced the parasite load by 86% after three weeks of daily topical treatment, while free CH8 was ineffective. In conclusion, LNC-CH8 has strong potential as a novel topical formulation for CL treatment.


Assuntos
Antiprotozoários , Leishmaniose Cutânea/tratamento farmacológico , Lipídeos , Nanoestruturas , Administração Tópica , Animais , Antiprotozoários/química , Antiprotozoários/farmacologia , Cápsulas , Feminino , Leishmania/metabolismo , Leishmaniose Cutânea/metabolismo , Leishmaniose Cutânea/patologia , Lipídeos/química , Lipídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Nanoestruturas/química , Nanoestruturas/uso terapêutico
7.
Artigo em Inglês | MEDLINE | ID: mdl-30012761

RESUMO

The oral efficacy and safety of a leishmanicidal nitrochalcone (CH8) were studied in BALB/c mouse infections with Leishmania amazonensis and Leishmania infantum Although 10-fold-higher doses of CH8 were needed to produce the same antiparasitic effect as that seen with the reference drug miltefosine, the latter was nephrotoxic, whereas CH8 restored disease toxicity markers to normal. This study shows the therapeutic potential of an orally active and hepato-/nephroprotective chalcone against cutaneous and visceral leishmaniases.


Assuntos
Antiprotozoários/química , Antiprotozoários/uso terapêutico , Chalconas/uso terapêutico , Leishmaniose/tratamento farmacológico , Administração Oral , Animais , Chalconas/química , Feminino , Leishmania/efeitos dos fármacos , Leishmania/patogenicidade , Leishmania infantum/efeitos dos fármacos , Leishmania infantum/patogenicidade , Leishmaniose/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Fosforilcolina/uso terapêutico
8.
Artigo em Inglês | MEDLINE | ID: mdl-29263064

RESUMO

Conventional chemotherapy of cutaneous leishmaniasis (CL) is based on multiple parenteral or intralesional injections with systemically toxic drugs. Aiming at a single-dose localized therapy, biodegradable poly(lactic-co-glycolic acid) (PLGA) microparticles loaded with 7.8% of an antileishmanial nitrochalcone named CH8 (CH8/PLGA) were constructed to promote sustained subcutaneous release. In vitro, murine macrophages avidly phagocytosed CH8/PLGA smaller than 6 µm without triggering oxidative mechanisms. Upon 48 h of incubation, both CH8 and CH8/PLGA were 40 times more toxic to intracellular Leishmania amazonensis than to macrophages. In vivo, BALB/c were given one or three subcutaneous injections in the infected ear with 1.2 mg/kg of CH8 in free or CH8/PLGA forms, whereas controls received three CH8-equivalent doses of naked PLGA microparticles or meglumine antimoniate (Glucantime; Sanofi-Aventis). Although a single injection with CH8/PLGA reduced the parasite loads by 91%, triple injections with free CH8 or CH8/PLGA caused 80 and 97% reductions, respectively, in relation to saline controls. Meglumine antimoniate treatment was the least effective (only 36% reduction) and the most toxic, as indicated by elevated alanine aminotransferase serum levels. Together, these findings show that CH8/PLGA microparticles can be effectively and safely used for single-dose treatment of CL.


Assuntos
Antiprotozoários/uso terapêutico , Chalconas/química , Leishmaniose Cutânea/tratamento farmacológico , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Antiprotozoários/química , Feminino , Leishmaniose Cutânea/metabolismo , Macrófagos Peritoneais/metabolismo , Macrófagos Peritoneais/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
Purinergic Signal ; 14(2): 201-211, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29680937

RESUMO

Leishmania amazonensis is the etiologic agent of cutaneous leishmaniasis, an immune-driven disease causing a range of clinical symptoms. Infections caused by L. amazonensis suppress the activation and function of immune cells, including macrophages, dendritic cells, and CD4+ T cells. In this study, we analyzed the course of infection as well as the leishmanicidal effect of intralesional UTP treatment in L. amazonensis-infected BALB/c mice. We found that UTP treatment reduced the parasitic load in both footpad and lymph node sites of infection. UTP also boosted Th1 immune responses, increasing CD4+ T cell recruitment and production of IFN-γ, IL-1ß, IL-12, and TNF-α. In addition, the role of UTP during innate immune response against L. amazonensis was evaluated using the air pouch model. We observed that UTP augmented neutrophil chemoattraction and activated microbicidal mechanisms, including ROS production. In conclusion, our data suggested an important role for this physiological nucleotide in controlling L. amazonensis infection, and its possible use as a therapeutic agent for shifting immune responses to Th1 and increasing host resistance against L. amazonensis infection.


Assuntos
Leishmaniose Cutânea/imunologia , Espécies Reativas de Oxigênio , Células Th1/efeitos dos fármacos , Uridina Trifosfato/farmacologia , Animais , Feminino , Leishmania mexicana , Camundongos , Camundongos Endogâmicos BALB C , Células Th1/imunologia
10.
Parasitology ; 145(2): 219-236, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28805165

RESUMO

Leishmaniasis is a vector-borne neglected tropical disease caused by protozoan parasites of the genus Leishmania for which there is a paucity of effective viable non-toxic drugs. There are 1·3 million new cases each year causing considerable socio-economic hardship, best measured in 2·4 million disability adjusted life years, with greatest impact on the poorest communities, which means that desperately needed new antileishmanial treatments have to be both affordable and accessible. Established medicines with cheaper and faster development times may hold the cure for this neglected tropical disease. This concept of using old drugs for new diseases may not be novel but, with the ambitious target of controlling or eradicating tropical diseases by 2020, this strategy is still an important one. In this review, we will explore the current state-of-the-art of drug repurposing strategies in the search for new treatments for leishmaniasis.


Assuntos
Antiprotozoários/farmacologia , Descoberta de Drogas/métodos , Reposicionamento de Medicamentos/métodos , Animais , Antiprotozoários/uso terapêutico , Descoberta de Drogas/tendências , Humanos , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Doenças Negligenciadas/tratamento farmacológico , Doenças Negligenciadas/parasitologia
11.
Phytochem Anal ; 29(3): 308-315, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29349835

RESUMO

INTRODUCTION: The medicinal plant Kalanchoe pinnata is a phenolic-rich species used worldwide. The reports on its pharmacological uses have increased by 70% in the last 10 years. The leaves of this plant are the main source of an unusual quercetin-diglycosyl flavonoid (QAR, quercetin arabinopyranosyl rhamnopyranoside), which can be easily extracted using water. QAR possess a strong in vivo anti-inflammatory activity. OBJECTIVE: To optimize the aqueous extraction of QAR from K. pinnata leaves using a three-level full factorial design. MATERIAL AND METHODS: After a previous screening design, time (x1 ) and temperature (x2 ) were chosen as the two independent variables for optimization. Freeze-dried leaves were extracted with water (20% w/v), at 30°C, 40°C or 50°C for 5, 18 or 30 min. QAR content (determined by HPLC-DAD) and yield of extracts were analyzed. The optimized extracts were also evaluated for cytotoxicity. RESULTS: The optimal heating times for extract yield and QAR content were similar in two-dimensional (2D) surface responses (between 12.8 and 30 min), but their optimal extraction temperatures were ranged between 40°C and 50°C for QAR content and 30°C and 38°C for extract yield. A compromise region for both parameters was at the mean points that were 40°C for the extraction temperature and 18 min for the total time. CONCLUSION: The optimized process is faster and spends less energy than the previous one (water; 30 min at 55°C); therefore is greener and more attractive for industrial purposes. This is the first report of extraction optimization of this bioactive flavonoid. Copyright © 2018 John Wiley & Sons, Ltd.


Assuntos
Anti-Inflamatórios/análise , Flavonoides/análise , Kalanchoe/química , Modelos Químicos , Folhas de Planta/química , Animais , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Flavonoides/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Espectrofotometria Ultravioleta
12.
Drug Dev Ind Pharm ; 44(9): 1473-1480, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29618227

RESUMO

Current chemotherapy of cutaneous leishmaniasis (CL), even the mildest forms, encompasses multiple and painful injections with toxic drugs that cause systemic adverse effects. Recently, we showed the promising use of poly(lactic-co-glycolic acid) (PLGA) microparticles loaded with an antileishmanial nitrosylated chalcone (CH8) for effective, safe, local, and single-dose treatment of CL. Here, we proposed to optimize the delivery system by increasing the CH8 loading in PLGA-microparticles using spray drying instead of emulsification-solvent evaporation. The effect of solvent composition and polymeric matrix changes on thermal properties, loading efficiency, particle size, morphology, and spatial drug distribution of the CH8-loaded microparticles was evaluated. The results showed that spray drying allowed a higher CH8 content (18% w/w), as contrasting with the previous solvent evaporation technique that maximally incorporated 7.8% of CH8. In vitro studies on 96-hour incubation with L. amazonensis-infected macrophages showed that entrapment in spray-dried PLGA microparticles rendered CH8 safer, preserved its antileishmanial activity, and did not affect its antioxidant properties.


Assuntos
Chalconas/química , Chalconas/farmacologia , Leishmaniose Cutânea/tratamento farmacológico , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Ácido Láctico/química , Microesferas , Tamanho da Partícula , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Polímeros/química , Solventes/química
13.
Purinergic Signal ; 13(2): 143-152, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27866341

RESUMO

Leishmania amazonensis is the etiological agent of diffuse cutaneous leishmaniasis. The immunopathology of leishmaniasis caused by L. amazonensis infection is dependent on the pathogenic role of effector CD4+ T cells. Purinergic signalling has been implicated in resistance to infection by different intracellular parasites. In this study, we evaluated the role of the P2X7 receptor in modulating the immune response and susceptibility to infection by L. amazonensis. We found that P2X7-deficient mice are more susceptible to L. amazonensis infection than wild-type (WT) mice. P2X7 deletion resulted in increased lesion size and parasite load. Our histological analysis showed an increase in cell infiltration in infected footpads of P2X7-deficient mice. Analysis of the cytokine profile in footpad homogenates showed increased levels of IFN-γ and decreased TGF-ß production in P2X7-deficient mice, suggesting an exaggerated pro-inflammatory response. In addition, we observed that CD4+ and CD8+ T cells from infected P2X7-deficient mice exhibit a higher proliferative capacity than infected WT mice. These data suggest that P2X7 receptor plays a key role in parasite control by regulating T effector cells and inflammation during L. amazonensis infection.


Assuntos
Leishmaniose Tegumentar Difusa/imunologia , Receptores Purinérgicos P2X7/imunologia , Animais , Inflamação/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T/imunologia
14.
Drug Dev Ind Pharm ; 43(9): 1519-1529, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28436310

RESUMO

Poly(N-vinylcaprolactam) (PNVCL) and poly(N-vinylcaprolactam-co-acrylic acid) (poly(NVCL-co-AA)) were synthesized by solution-free radical polymerization and displayed thermo-responsive behavior, with lower critical solution temperatures (LCSTs) of 35 °C and 39 °C, respectively. The incorporation of AA unities made the poly(NVCL-co-AA) sensitive to both pH and temperature. They were exploited in this work in preparing microparticles loaded with ketoprofen via spray-drying to modulate the drug release rate by changing pH or temperature. The interaction between polymer and drug was studied using X-ray diffractometry, Raman spectrometry and scanning electron microscopy (SEM). The biocompatibility of pure polymers, free ketoprofen as well as the spray-dried particles was demonstrated in vitro by low cytotoxicity and a lack of nitric oxide production in macrophages at concentrations as high as 100 µg/ml. The release profile of ketoprofen was evaluated by in vitro assays at different temperatures and pH values. Drug diffusion out of PNVCL's hydrated polymer network is increased at temperatures below the LCST. However, when poly(NVCL-co-AA) was used as the matrix, the release of ketoprofen was primarily controlled by the pH of the medium. These results indicated that PNVCL and the novel poly(NVCL-co-AA) could be promising candidates for pH and temperature-responsive drug delivery systems.


Assuntos
Acrilatos/química , Caprolactama/análogos & derivados , Cetoprofeno/síntese química , Polímeros/síntese química , Caprolactama/síntese química , Caprolactama/química , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos , Concentração de Íons de Hidrogênio , Cetoprofeno/química , Tamanho da Partícula , Polímeros/química , Temperatura
15.
Parasitology ; 142(13): 1640-6, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26394776

RESUMO

The CAF01 adjuvant has previously been shown to be safe for human use and to be a potent adjuvant for several vaccine antigens. In the present work, we sought to optimize the Leishmania amazonensis antigens (LaAg) intranasal vaccine in an attempt to enhance the protective immune responses against Leishmania (infantum) chagasi by using the CAF01 association. LaAg/CAF01 vaccinated mice that were challenged 15 days after booster dose with L. (infantum) chagasi showed a significant reduction in their parasite burden in both the spleen and liver, which is associated with an increase in specific production of IFN-γ and nitrite, and a decrease in IL-4 production. In addition, LaAg/CAF01 intranasal delivery was able to increase lymphoproliferative immune responses after parasite antigen recall. These results suggest the feasibility of using the intranasal route for the delivery of crude antigens and of a human-compatible adjuvant against visceral leishmaniasis.


Assuntos
Antígenos de Protozoários/imunologia , Leishmania infantum/imunologia , Leishmania mexicana/imunologia , Leishmaniose Visceral/prevenção & controle , Vacinas Protozoárias/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Administração Intranasal , Animais , Anticorpos Antiprotozoários/sangue , Citocinas/biossíntese , Epitopos , Feminino , Imunidade Celular , Imunoglobulina G/sangue , Fígado/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Nitritos/metabolismo , Baço/citologia , Baço/imunologia , Baço/parasitologia , Vacinas de Produtos Inativados/administração & dosagem
16.
J Nanosci Nanotechnol ; 15(1): 827-37, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26328447

RESUMO

Lipid-core polymeric nanocapsules are innovative devices that present distinguished characteristics due to the presence of sorbitan monostearate into the oily-core. This component acted as low-molecular-mass organic gelator for the oil (medium chain triglycerides). The organogel-structured core influenced the polymeric wall characteristics disfavoring the formation of more stable polymer crystallites. This probably occurred due to interpenetration of these pseudo-phases. Sorbitan monostearate dispersed in the oily-core was also able to interact by non-covalent bonding with the drugs increasing the drug loading capacity more than 40 times compared to conventional nanocapsules. We demonstrated that the drug-models quercetin and quercetin pentaacetate stabilized the organogel network probably due to interactions of the drug molecules with the sorbitan monostearate headgroups by hydrogen bonding.


Assuntos
Hexoses/química , Lipídeos/química , Nanocápsulas/química , Tamanho da Partícula , Quercetina/química , Espalhamento a Baixo Ângulo , Difração de Raios X
17.
Acta Trop ; 252: 107125, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38280636

RESUMO

There are no approved vaccines yet for human visceral leishmaniasis (VL), the most severe form of the leishmaniasis clinical manifestations that is fatal in over 95 % of untreated cases. It is well-accepted that immunological changes during aging have deleterious impact on the efficacy of vaccines and response to infections. In this work, we compared the response of young and aged mice to intranasal vaccination with killed Leishmania amazonensis promastigote antigens (LaAg) that were then challenged with L. infantum infection, a species that causes visceral leishmaniasis. Intranasal vaccination with LaAg induced a similar reduction in parasitism and hepatosplenomegaly in both young and aged mice compared to their unvaccinated counterparts. Following infection, there was also a less prominent inflammatory profile particularly in the vaccinated aged group, with lower production of TNF-α and nitrite compared to the respective unvaccinated group. Interestingly, the LaAg intranasal vaccination promoted increased production of IFN-γ that was observed in both young- and aged vaccinated groups. Additionally, CD4+ and CD8+T cells from both vaccinated groups presented decreased expression of the inhibitory receptors PD-1 and KLRG1 compared to their unvaccinated controls. Interestingly, a strong positive correlation was observed between the expression of both inhibitory receptors PD-1 and KLRG1 and parasitism, which was more conspicuous in the unvaccinated-aged mice than in the others. Overall, this study helps define new strategies to improve vaccine effectiveness and provides a perspective for prophylactic alternatives against leishmaniasis.


Assuntos
Leishmania infantum , Leishmania mexicana , Vacinas contra Leishmaniose , Leishmaniose Visceral , Leishmaniose , Vacinas Protozoárias , Humanos , Animais , Camundongos , Idoso , Leishmaniose Visceral/prevenção & controle , Receptor de Morte Celular Programada 1 , Antígenos de Protozoários , Camundongos Endogâmicos BALB C , Citocinas
18.
Cell Physiol Biochem ; 32(3): 699-718, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24080824

RESUMO

BACKGROUND/AIMS: Diabetic nephropathy is one of the main causes of end-stage renal disease. The present study investigated the effect of mononuclear cell (MC) therapy in rats subjected to diabetic nephropathy. METHODS: Male Wistar rats were divided into control (CTRL), diabetic (DM), CTRL+MC and DM+MC groups. Diabetes was induced by a single injection of streptozotocin (45 mg/kg, i.p.) and, 4 weeks later, 2×10(7) MCs were injected via the jugular vein. RESULTS: The rats in the DM and DM+MC groups showed increased glycemia, glomerular filtration rate and glomerular tuff area versus control groups. The glomerular filtration rate and glomerular tuff area were normalized in the DM+MC group. No alterations were observed in the fractional excretion of electrolytes and proteinuria between the DM and DM+MC groups. TGF-ß1 protein levels in the DM group were significantly increased versus control animals and normalized in the DM+MC group. An increase in ED1(+)/arginase I(+) macrophages and IL-10 renal expression was observed in the DM+MC group versus DM group. CONCLUSIONS: Bone marrow-derived MC therapy was able to prevent glomerular alterations and TGF-ß1 protein overexpression and modulated glomerular arginase I(+) macrophage infiltration in rats subjected to early diabetic nephropathy.


Assuntos
Células da Medula Óssea/citologia , Diabetes Mellitus Experimental/cirurgia , Nefropatias Diabéticas/cirurgia , Leucócitos Mononucleares/transplante , Animais , Arginase/metabolismo , Glicemia/análise , Peso Corporal , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/patologia , Ectodisplasinas/metabolismo , Taxa de Filtração Glomerular , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Rim/patologia , Leucócitos Mononucleares/citologia , Macrófagos/metabolismo , Masculino , Proteinúria , Ratos , Ratos Wistar , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
J Immunol ; 187(1): 141-50, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21646294

RESUMO

Gut-associated dendritic cells (DC) synthesize all-trans retinoic acid, which is required for inducing gut-tropic lymphocytes. Gut-associated DC from MyD88(-/-) mice, which lack most TLR signals, expressed low levels of retinal dehydrogenases (critical enzymes for all-trans retinoic acid biosynthesis) and were significantly impaired in their ability to induce gut-homing T cells. Pretreatment of extraintestinal DC with a TLR1/2 agonist was sufficient to induce retinal dehydrogenases and to confer these DC with the capacity to induce gut-homing lymphocytes via a mechanism dependent on MyD88 and JNK/MAPK. Moreover, gut-associated DC from TLR2(-/-) mice, or from mice in which JNK was pharmacologically blocked, were impaired in their education to imprint gut-homing T cells, which correlated with a decreased induction of gut-tropic T cells in TLR2(-/-) mice upon immunization. Thus, MyD88-dependent TLR2 signals are necessary and sufficient to educate DC with gut-specific imprinting properties and contribute in vivo to the generation of gut-tropic T cells.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Impressão Genômica/imunologia , Mucosa Intestinal/imunologia , Fator 88 de Diferenciação Mieloide/fisiologia , Transdução de Sinais/imunologia , Receptor 1 Toll-Like/fisiologia , Receptor 2 Toll-Like/fisiologia , Animais , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Técnicas de Cocultura , Células Dendríticas/citologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Melanoma Experimental , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Fator 88 de Diferenciação Mieloide/deficiência , Fator 88 de Diferenciação Mieloide/genética , Quimera por Radiação , Receptores de Retorno de Linfócitos/deficiência , Receptores de Retorno de Linfócitos/genética , Receptores de Retorno de Linfócitos/fisiologia , Transdução de Sinais/genética
20.
Vaccine X ; 15: 100403, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38026045

RESUMO

Intranasal (i.n.) vaccination with adjuvant-free plasmid DNA encoding the leishmanial antigen LACK (LACK DNA) has shown to induce protective immunity against both cutaneous and visceral leishmaniasis in rodents. In the present work, we sought to evaluate the safety and effectiveness of d,l-glyceraldehyde cross-linked chitosan microparticles (CCM) as a LACK DNA non-intumescent mucoadhesive delivery system. CCM with 5 µm of diameter was prepared and adsorbed with a maximum of 2.4 % (w/w) of DNA with no volume alteration. Histological analysis of mouse nostrils instilled with LACK DNA / CCM showed microparticles to be not only mucoadherent but also mucopenetrant, inducing no local inflammation. Systemic safeness was confirmed by the observation that two nasal instillations one week apart did not alter the numbers of bronchoalveolar cells or blood eosinophils; did not alter ALT, AST and creatinine serum levels; and did not induce cutaneous hypersensitivity. When challenged in the footpad with Leishmania amazonensis, mice developed significantly lower parasite loads as compared with animals given naked LACK DNA or CCM alone. That was accompanied by increased stimulation of Th1-biased responses, as seen by the higher T-bet / GATA-3 ratio and IFN-γ levels. Together, these results demonstrate that CCM is a safe and effective mucopenetrating carrier that can increase the efficacy of i.n. LACK DNA vaccination against cutaneous leishmaniasis.

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