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1.
Int J Nanomedicine ; 19: 2655-2673, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38500680

RESUMO

Introduction: Immunotherapy has revolutionized cancer treatment by harnessing the immune system to enhance antitumor responses while minimizing off-target effects. Among the promising cancer-specific therapies, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has attracted significant attention. Methods: Here, we developed an ionizable lipid nanoparticle (LNP) platform to deliver TRAIL mRNA (LNP-TRAIL) directly to the tumor microenvironment (TME) to induce tumor cell death. Our LNP-TRAIL was formulated via microfluidic mixing and the induction of tumor cell death was assessed in vitro. Next, we investigated the ability of LNP-TRAIL to inhibit colon cancer progression in vivo in combination with a TME normalization approach using Losartan (Los) or angiotensin 1-7 (Ang(1-7)) to reduce vascular compression and deposition of extracellular matrix in mice. Results: Our results demonstrated that LNP-TRAIL induced tumor cell death in vitro and effectively inhibited colon cancer progression in vivo, particularly when combined with TME normalization induced by treatment Los or Ang(1-7). In addition, potent tumor cell death as well as enhanced apoptosis and necrosis was found in the tumor tissue of a group treated with LNP-TRAIL combined with TME normalization. Discussion: Together, our data demonstrate the potential of the LNP to deliver TRAIL mRNA to the TME and to induce tumor cell death, especially when combined with TME normalization. Therefore, these findings provide important insights for the development of novel therapeutic strategies for the immunotherapy of solid tumors.


Assuntos
Neoplasias do Colo , Lipossomos , Nanopartículas , Microambiente Tumoral , Animais , Camundongos , Ligantes , Apoptose , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Fator de Necrose Tumoral alfa , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
2.
Sci Rep ; 14(1): 6991, 2024 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-38523180

RESUMO

Gout and hyperuricemia are characterized by high uric acid levels, and their treatment involves medications that have adverse effects. In this study, we evaluated oral liposomal formulations with eremantholide C and goyazensolide as a novel approach to reduce the toxicity associated with these substances while maintaining their anti-hyperuricemic activity. We characterized the formulations and evaluated them based on encapsulation efficiency and stability over 12 months and under simulated physiological environments. We determined the toxicity of the liposomal formulations in Caco-2 cells and the anti-hyperuricemic activity in rats. The formulations exhibited nanometric size, a narrow size distribution, and a negative zeta potential, indicating their stability and uniformity. The efficient encapsulation of the sesquiterpene lactones within the liposomes emphasizes their potential for sustained release and therapeutic efficacy. Stability evaluation revealed a small decrease in the eremantholide C concentration and a remarkable stability in the goyazensolide concentration. In Caco-2 cells, the liposomes did not exert toxicity, but did exhibit an antiproliferative effect. In vivo assays demonstrated that the liposomes reduced serum uric acid levels. Our study represents an advancement in gout and hyperuricemia treatment. The liposomal formulations effectively reduced the toxicity associated with the sesquiterpene lactones while maintaining their therapeutic effects.


Assuntos
Artrite Gotosa , Hidrocarbonetos Aromáticos com Pontes , Furanos , Gota , Hiperuricemia , Sesquiterpenos , Sesterterpenos , Humanos , Ratos , Animais , Lipossomos/uso terapêutico , Ácido Úrico/uso terapêutico , Hiperuricemia/tratamento farmacológico , Células CACO-2 , Gota/tratamento farmacológico , Lactonas/farmacologia , Lactonas/uso terapêutico
3.
Nanomedicine (Lond) ; 19(5): 383-396, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38293893

RESUMO

Aim: To develop nanoemulsions (NEs) loading amphotericin B (AmB) and to evaluate the influence of different excipients on the stability and the supramolecular organization, retention and toxicity of AmB. Materials & methods: The NEs were developed from different oils, surfactants, external media and anionic lipids (disteaoryl phosphatidylglycerol [DSPG] and dioleoyl phosphatidylglycerol [DOPG]). Their impact on the size, pH, zeta potential, AmB encapsulation efficiency, AmB retention and hemolytic potential of the NEs was evaluated. Results & conclusion: The use of soybean oil (lipid matrix), Span 80 (surfactant), phosphate buffer (external phase) and DSPG or DOPG (hydrophobic ion pair) provided better NE stability, higher AmB retention within the NEs and a safer formulation profile in hemolysis tests.


Assuntos
Anfotericina B , Fosfatidilgliceróis , Anfotericina B/toxicidade , Tensoativos , Antifúngicos/química
4.
Nat Commun ; 15(1): 590, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238326

RESUMO

A safe and effective vaccine with long-term protection against SARS-CoV-2 variants of concern (VOCs) is a global health priority. Here, we develop lipid nanoparticles (LNPs) to provide safe and effective delivery of plasmid DNA (pDNA) and show protection against VOCs in female small animal models. Using a library of LNPs encapsulating unique barcoded DNA (b-DNA), we screen for b-DNA delivery after intramuscular administration. The top-performing LNPs are further tested for their capacity of pDNA uptake in antigen-presenting cells in vitro. The lead LNP is used to encapsulate pDNA encoding the HexaPro version of SARS-CoV-2 spike (LNP-HPS) and immunogenicity and protection is tested in vivo. LNP-HPS elicit a robust protective effect against SARS-CoV-2 Gamma (P.1), correlating with reduced lethality, decreased viral load in the lungs and reduced lung damage. LNP-HPS induce potent humoral and T cell responses against P.1, and generate high levels of neutralizing antibodies against P.1 and Omicron (B.1.1.529). Our findings indicate that the protective efficacy and immunogenicity elicited by LNP-HPS are comparable to those achieved by the approved COVID-19 vaccine from Biontech/Pfizer in animal models. Together, these findings suggest that LNP-HPS hold great promise as a vaccine candidate against VOCs.


Assuntos
COVID-19 , DNA de Forma B , Vacinas de DNA , Feminino , Animais , Humanos , SARS-CoV-2/genética , Vacinas de DNA/genética , 60547 , Vacinas contra COVID-19 , COVID-19/prevenção & controle , DNA , Anticorpos Neutralizantes , Anticorpos Antivirais
5.
Biophys Rev ; 15(4): 751-765, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37681109

RESUMO

The pentavalent meglumine antimoniate (MA) is still a first-line drug in the treatment of leishmaniasis in several countries. As an attempt to elucidate its mechanism of action and develop new antimonial drugs with improved therapeutic profile, Sb(V) complexes with different ligands, including ß-cyclodextrin (ß-CD), nucleosides and non-ionic surfactants, have been studied. Interestingly, Sb(V) oxide, MA, its complex with ß-CD, Sb(V)-guanosine complex and amphiphilic Sb(V) complexes with N-alkyl-N-methylglucamide, have shown marked tendency to self-assemble in aqueous solutions, forming nanoaggregates, hydrogel or micelle-like nanoparticles. Surprisingly, the resulting assemblies presented in most cases slow dissociation kinetics upon dilution and a strong influence of pH, which impacted on their pharmacokinetic and therapeutic properties against leishmaniasis. To explain this unique property, we raised the hypothesis that multiple pnictogen bonds could contribute to the formation of these assemblies and their kinetic of dissociation. The present article reviews our current knowledge on the structural organization and physicochemical characteristics of Sb-based supramolecular assemblies, as well as their pharmacological properties and potential for treatment of leishmaniasis. This review supports the feasibility of the rational design of new Sb(V) complexes with supramolecular assemblies for the safe and effective treatment of leishmaniasis.

6.
Drug Deliv Transl Res ; 13(5): 1420-1435, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36749480

RESUMO

The use of implantable biomaterials to replace physiological and anatomical functions has been widely investigated in the clinic. However, the selection of biomaterials is crucial for long-term function, and the implantation of certain biomaterials can cause inflammatory and fibrotic processes, triggering a foreign body reaction that leads to loss of function and consequent need for removal. Specifically, the Wnt signaling pathway controls the healing process of the human body, and its dysregulation can result in inflammation and fibrosis, such as in peritoneal fibrosis. Here, we assessed the effects of daily oral administration of a Wnt pathway inhibitor complex (CD:LGK974) to reduce the inflammatory, fibrotic, and angiogenic processes caused by intraperitoneal implants. CD:LGK974 significantly reduced the infiltration of immune cells and release of inflammatory cytokines in the implant region compared to the control groups. Furthermore, CD:LGK974 inhibited collagen deposition and reduced the expression of pro-fibrotic α-SMA and TGF-ß1, confirming fibrosis reduction. Finally, the CD:LGK974 complex decreased VEGF levels and both the number and area of blood vessels formed, suggesting decreased angiogenesis. This work introduces a potential new application of the Wnt inhibitor complex to reduce peritoneal fibrosis and the rejection of implants at the intraperitoneal site, possibly allowing for longer-term functionality of existing clinical biomaterials.


Assuntos
Fibrose Peritoneal , Humanos , Fibrose Peritoneal/complicações , Fator A de Crescimento do Endotélio Vascular/metabolismo , Inflamação/tratamento farmacológico , Inflamação/etiologia , Reação a Corpo Estranho/etiologia , Reação a Corpo Estranho/metabolismo , Cicatrização
7.
Nanomedicine (Lond) ; 17(18): 1237-1251, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36189757

RESUMO

Aim: Amphotericin B (AmB) is an antileishmanial drug with high toxicity; however, this drawback might overcome by decreasing the AmB self-aggregation state. This work aimed at evaluating the influence of cholesterol on the aggregation state of AmB loaded in a nanoemulsion (NE-AmB) for the treatment of cutaneous leishmaniasis. NE-AmB (1, 4 and 8 mg/kg/day) was administered intravenously to animals infected by Leishmania major every 2 days for a total of five injections. Results: Ultraviolet-visible spectroscopy and circular dichroism studies demonstrated that cholesterol reduced AmB aggregation state in NE. NE-AmB was stable after 180 days, and its hemolytic toxicity was lower than that observed for the conventional AmB. NE-AmB administered intravenously into animals infected by Leishmania major at 8 mg/kg was capable of stabilizing the lesion size and reducing the parasitic load. Conclusion: These findings support the NE potential as a stable nanocarrier for AmB in the treatment of cutaneous leishmaniasis.


Assuntos
Antiprotozoários , Leishmania major , Leishmaniose Cutânea , Animais , Anfotericina B/farmacologia , Anfotericina B/uso terapêutico , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Leishmaniose Cutânea/tratamento farmacológico , Colesterol
8.
Pharmaceutics ; 14(8)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36015369

RESUMO

This work aims to evaluate whether nanoassemblies (NanoSb) made from antimony(V) complexes with octanoyl-N-methylglucamide (SbL8) or decanoyl-N-methylglucamide (SbL10) would effectively target the infection sites in visceral and cutaneous leishmaniases (VL and CL). NanoSb were investigated regarding stability at different pHs, accumulation of Sb in the macrophage host cell and liver, and in vitro and in vivo activities in models of leishmaniasis. The kinetic stability assay showed that NanoSb are stable at neutral pH, but release incorporated lipophilic substance after conformational change in media that mimic the gastric fluid and the parasitophorous vacuole. NanoSb promoted greater accumulation of Sb in macrophages and in the liver of mice after parenteral administration, when compared to conventional antimonial Glucantime®. SbL10 was much more active than Glucantime® against intramacrophage Leishmania amastigotes and less cytotoxic than SbL8 against macrophages. The in vitro SbL10 activity was further enhanced with co-incorporated miltefosine. NanoSb showed high antileishmanial activity in the L. donovani murine VL after parenteral administration and moderate activity in the L. amazonensis murine CL after topical treatment. This study supports the ability of NanoSb to effectively deliver a combination of Sb and co-incorporated drug to host cell and infected tissues, in a better way than Glucantime® does.

9.
Int J Nanomedicine ; 17: 2865-2881, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35795081

RESUMO

Introduction: Gene therapy is a promising approach to be applied in cardiac regeneration after myocardial infarction and gene correction for inherited cardiomyopathies. However, cardiomyocytes are crucial cell types that are considered hard-to-transfect. The entrapment of nucleic acids in non-viral vectors, such as lipid nanoparticles (LNPs), is an attractive approach for safe and effective delivery. Methods: Here, a mini-library of engineered LNPs was developed for pDNA delivery in cardiomyocytes. LNPs were characterized and screened for pDNA delivery in cardiomyocytes and identified a lead LNP formulation with enhanced transfection efficiency. Results: By varying lipid molar ratios, the LNP formulation was optimized to deliver pDNA in cardiomyocytes with enhanced gene expression in vitro and in vivo, with negligible toxicity. In vitro, our lead LNP was able to reach a gene expression greater than 80%. The in vivo treatment with lead LNPs induced a twofold increase in GFP expression in heart tissue compared to control. In addition, levels of circulating myeloid cells and inflammatory cytokines remained without significant changes in the heart after LNP treatment. It was also demonstrated that cardiac cell function was not affected after LNP treatment. Conclusion: Collectively, our results highlight the potential of LNPs as an efficient delivery vector for pDNA to cardiomyocytes. This study suggests that LNPs hold promise to improve gene therapy for treatment of cardiovascular disease.


Assuntos
Lipídeos , Miócitos Cardíacos , DNA/genética , Lipossomos , Nanopartículas , Plasmídeos/genética
10.
Pharmaceutics ; 14(5)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35631575

RESUMO

Liposomal amphotericin B (AmB) or AmBisome® is the most effective and safe therapeutic agent for visceral leishmaniasis (VL), but its clinical efficacy is limited in cutaneous leishmaniasis (CL) and HIV/VL co-infection. The aim of this work was to develop a formulation of AmB in PEGylated liposomes and compare its efficacy to AmBisome® in a murine model of CL. Formulations of AmB in conventional and PEGylated liposomes were characterized for particle size and morphology, drug encapsulation efficiency and aggregation state. Those were compared to AmBisome® in Leishmania amazonensis-infected BALB/c mice for their effects on the lesion size growth and parasite load. The conventional and PEGylated formulations showed vesicles with 100-130 nm diameter and low polydispersity, incorporating more than 95% of AmB under the non-aggregated form. Following parenteral administration in the murine model of CL, the PEGylated formulation of AmB significantly reduced the lesion size growth and parasite load, in comparison to control groups, in contrast to conventional liposomal AmB. The PEGylated formulation of AmB was also effective when given by oral route on a 2-day regimen. This work reports for the first time that PEGylated liposomal AmB can improve the treatment of experimental cutaneous leishmaniasis by both parenteral and oral routes.

11.
Molecules ; 27(7)2022 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-35408712

RESUMO

There is a need for new, cost-effective drugs to treat leishmaniasis. A strategy based on traditional medicine practiced in Bolivia led to the discovery of the 2-substituted quinoline series as a source of molecules with antileishmanial activity and low toxicity. This review documents the development of the series from the first isolated natural compounds through several hundred synthetized molecules to an optimized compound exhibiting an in vitro IC50 value of 0.2 µM against Leishmania donovani, and a selectivity index value of 187, together with in vivo activity on the L. donovani/hamster model. Attempts to establish structure-activity relationships are described, as well as studies that have attempted to determine the mechanism of action. For the latter, it appears that molecules of this series act on multiple targets, possibly including the immune system, which could explain the observed lack of drug resistance after in vitro drug pressure. We also show how nanotechnology strategies could valorize these drugs through adapted formulations and how a mechanistic targeting approach could generate new compounds with increased activity.


Assuntos
Antiprotozoários , Leishmania donovani , Leishmaniose , Quinolinas , Animais , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Cricetinae , Leishmaniose/tratamento farmacológico , Quinolinas/farmacologia , Quinolinas/uso terapêutico , Relação Estrutura-Atividade
12.
Pharmaceutics ; 15(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36678729

RESUMO

The liposomal amphotericin B (AmB) formulation, AmBisome®, still represents the best therapeutic option for cutaneous and visceral leishmaniasis. However, its clinical efficacy depends on the patient's immunological status, the clinical manifestation and the endemic region. Moreover, the need for parenteral administration, its side effects and high cost significantly limit its use in developing countries. This review reports the progress achieved thus far toward the understanding of the mechanism responsible for the reduced toxicity of liposomal AmB formulations and the factors that influence their efficacy against leishmaniasis. It also presents the recent advances in the development of more effective liposomal AmB formulations, including topical and oral liposome formulations. The critical role of the AmB aggregation state and release rate in the reduction of drug toxicity and in the drug efficacy by non-invasive routes is emphasized. This paper is expected to guide future research and development of innovative liposomal formulations of AmB.

13.
Mol Immunol ; 141: 70-78, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34814056

RESUMO

This study compared the therapeutic potential of the chemotherapy using meglumine antimoniate encapsulated in a mixture of conventional and PEGylated liposomes (Nano Sbv) and immunotherapy with anti-canine IL-10 receptor-blocking monoclonal antibody (Anti IL-10R) on canine visceral leishmaniasis (CVL). Twenty mongrel dogs naturally infected by L. infantum, displaying clinical signs of visceral leishmaniasis were randomly divided in two groups. In the first one, nine dogs received six intravenous doses of a mixture of conventional and PEGylated liposomes containing meglumine antimoniate at 6.5 mg Sb/kg/dose. In the second one, eleven dogs received two intramuscular doses of 4 mg of anti-canine IL-10 receptor-blocking monoclonal antibody. The animals were evaluated before (T0) and 30, 90, and 180 days after treatments. Our major results demonstrated that both treatments were able to maintain hematological and biochemical parameters, increase circulating T lymphocytes subpopulations, increase the IFN-γ producing T-CD4 lymphocytes, restore the lymphoproliferative capacity and improve the clinical status. However, although these improvements were observed in the initial post-treatment times, they did not maintain until the end of the experimental follow-up. We believe that the use of booster doses or the association of chemotherapy and immunotherapy (immunochemotherapy) is promising to improve the effectiveness of treating CVL for improving the clinical signs and possibly reducing the parasite burden in dogs infected with Leishmania infantum.


Assuntos
Anticorpos Monoclonais/farmacologia , Doenças do Cão/tratamento farmacológico , Leishmaniose Visceral/tratamento farmacológico , Lipossomos/química , Antimoniato de Meglumina/farmacologia , Polietilenoglicóis/química , Receptores de Interleucina-10/antagonistas & inibidores , Alopurinol/farmacologia , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Doenças do Cão/metabolismo , Cães , Fatores Imunológicos/metabolismo , Imunoterapia/métodos , Leishmania infantum/efeitos dos fármacos , Leishmaniose Visceral/metabolismo , Compostos Organometálicos/farmacologia
14.
J Liposome Res ; 31(2): 169-176, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32228210

RESUMO

Leishmaniasis is a parasitic disease treatable and curable, however, the chemotherapeutic agents for their treatment are limited. In South American countries, pentavalent antimonials are still the first line of treatment for cutaneous leishmaniasis with an efficacy of about 75%, but the toxicity of the drug causes serious side effects and remains as the main obstacle for treatment. New knowledge aimed to improve drug delivery into the intracellular environment is essential, especially for drugs currently used in the clinic, to develop new anti-Leishmania formulations. In the present study, we analysed the scientific literature to highlight the progress achieved in the last decade regarding the use of nanotechnology for improving the current leishmaniasis treatments. Results allowed us to conclude that the encapsulated Glucantime liposomal formulation can be improved by means of nanoparticle functionalization processes, resulting in new drug delivery systems that can be potentially proposed as alternative therapies for leishmaniasis treatment.


Assuntos
Antiprotozoários , Leishmaniose Cutânea , Leishmaniose , Nanopartículas , Antiprotozoários/uso terapêutico , Sistemas de Liberação de Medicamentos , Humanos , Leishmaniose/tratamento farmacológico , Leishmaniose Cutânea/tratamento farmacológico , Lipossomos/uso terapêutico
15.
Biomed Pharmacother ; 134: 111120, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341671

RESUMO

Visceral leishmaniasis (VL) is a systemic parasitic disease that leads to high rates of morbidity and mortality in humans worldwide. There is a great need to develop new drugs and novel strategies to make chemotherapy for this disease more efficacious and well tolerated. Recent reports on the immunomodulatory effects and the low toxicity of the spherical carbon nanostructure fullerol led us to investigate in vitro and in vivo antileishmanial activity in free and encapsulated forms in liposomes. When assayed against intramacrophagic Leishmania amastigotes, fullerol showed a dose-dependent reduction of the infection index with IC50 of 0.042 mg/mL. When given daily by i.p. route for 20 days (0.05 mg/kg/d) in a murine model of acute VL, fullerol promoted significant reduction in the liver parasite load. To improve the delivery of fullerol to the infection sites, liposomal formulations were prepared by the dehydration-rehydration method. When evaluated in the acute VL model, liposomal fullerol (Lip-Ful) formulations given i.p. at 0.05 and 0.2 mg/kg with 4-days intervals were more effective than the free form, with significant parasite reductions in both liver and spleen. Lip-Ful at 0.2 mg/kg promoted complete parasite elimination in the liver. The antileishmanial activity of Lip-Ful was further confirmed in a chronic model of VL. Lip-Ful was also found to induce secretion of pro-inflammatory TNF-α, IFN-γ and IL-1ß cytokines. In conclusion, this work reports for the first time the antileishmanial activity of fullerol and introduces an innovative approach for treatment of VL based on the association of this nanostructure with liposomes.


Assuntos
Fulerenos/farmacologia , Leishmania infantum/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Lipídeos/química , Fígado/parasitologia , Macrófagos Peritoneais/parasitologia , Tripanossomicidas/farmacologia , Animais , Citocinas/sangue , Modelos Animais de Doenças , Composição de Medicamentos , Feminino , Fulerenos/química , Mediadores da Inflamação/sangue , Leishmania infantum/crescimento & desenvolvimento , Leishmania mexicana/crescimento & desenvolvimento , Leishmaniose Visceral/sangue , Leishmaniose Visceral/parasitologia , Lipossomos , Fígado/metabolismo , Mesocricetus , Camundongos Endogâmicos BALB C , Nanopartículas , Carga Parasitária , Tripanossomicidas/química
16.
Int J Pharm ; 586: 119390, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32540349

RESUMO

Re-emergence and geographic expansion of leishmaniasis is accelerating efforts to develop a safe and effective Leshmania vaccine. Vaccines using Leishmania recombinant antigens, such as LiHyp1, which is mostly present in the amastigote parasite form, are being developed as a next generation to crude killed parasite-based vaccines. The main objective of this work was to develop a LiHyp1-based vaccine and determine if it can induce protective immunity in BALB/c mice when administered using a dissolvable microneedle (DMN) patch by the skin route. The LiHyp1 antigen was incorporated into cationic liposomes (CL), with or without the TLR9 agonist, CpG. The LiHyp1-liposomal vaccines were characterized with respect to size, protein encapsulation rates and retention of their physical characteristics after incorporation into the DMN patch. DMN mechanical strength and skin penetration ability were tested. A vaccine composed of LiHyp1, CpG and liposomes and subcutaneously injected or a vaccine containing antigen and CpG in DMN patches, without liposomes, induced high antibody responses and significant levels of protection against L. donovani parasite infection. This study progresses the development of an efficacious leishmania vaccine by detailing promising vaccine formulations and skin delivery technologies and it addresses protective efficacy of a liposome-based dissolvable microneedle patch vaccine system.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Vacinas contra Leishmaniose/administração & dosagem , Leishmaniose/prevenção & controle , Receptor Toll-Like 9/imunologia , Animais , Antígenos de Protozoários/administração & dosagem , Antígenos de Protozoários/imunologia , Cátions , Feminino , Imunização , Injeções Subcutâneas , Vacinas contra Leishmaniose/farmacocinética , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Absorção Cutânea , Adesivo Transdérmico
17.
ACS Infect Dis ; 6(5): 1121-1139, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32283915

RESUMO

The drugs currently used to treat leishmaniases have limitations concerning cost, efficacy, and safety, making the search for new therapeutic approaches urgent. We found that the gold(I)-derived complexes were active against L. infantum and L. braziliensis intracellular amastigotes with IC50 values ranging from 0.5 to 5.5 µM. All gold(I) complexes were potent inhibitors of trypanothione reductase (TR), with enzyme IC50 values ranging from 1 to 7.8 µM. Triethylphosphine-derived complexes enhanced reactive oxygen species (ROS) production and decreased mitochondrial respiration after 2 h of exposure, indicating that gold(I) complexes cause oxidative stress by direct ROS production, by causing mitochondrial damage or by impairing TR activity and thus accumulating ROS. There was no cross-resistance to antimony; in fact, SbR (antimony-resistant mutants) strains were hypersensitive to some of the complexes. BALB/c mice infected with luciferase-expressing L. braziliensis or L. amazonensis and treated orally with 12.5 mg/kg/day of AdT Et (3) or AdO Et (4) presented reduced lesion size and parasite burden, as revealed by bioimaging. The combination of (3) and miltefosine allowed for a 50% reduction in miltefosine treatment time. Complexes 3 and 4 presented favorable pharmacokinetic and toxicity profiles that encourage further drug development studies. Gold(I) complexes are promising antileishmanial agents, with a potential for therapeutic use, including in leishmaniasis caused by antimony-resistant parasites.


Assuntos
Antiprotozoários/farmacologia , Ouro/farmacologia , Leishmaniose , NADH NADPH Oxirredutases/antagonistas & inibidores , Animais , Leishmaniose/tratamento farmacológico , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo
18.
Artigo em Inglês | MEDLINE | ID: mdl-32284386

RESUMO

The treatment of dogs naturally infected with Leishmania infantum using meglumine antimoniate (MA) encapsulated in conventional liposomes (LC) in association with allopurinol has been previously reported to promote a marked reduction in the parasite burden in the main infection sites. Here, a new assay in naturally infected dogs was performed using a novel liposome formulation of MA consisting of a mixture of conventional and long-circulating (PEGylated) liposomes (LCP), with expected broader distribution among affected tissues of the mononuclear phagocyte system. Experimental groups of naturally infected dogs were as follows: LCP plus Allop, receiving LCP intravenously as 2 cycles of 6 doses (6.5 mg Sb/kg of body weight/dose) at 4-day intervals plus allopurinol at 30 mg/kg/12 h per os (p.o.) during 130 days (LCP+Allop); LC plus Allop, receiving LC intravenously as 2 cycles of 6 doses (6.5 mg Sb/kg/dose) plus allopurinol during 130 days (LC+Allop); Allop, treated with allopurinol only; and a nontreated control. Parasite loads were evaluated by quantitative PCR in liver, spleen, and bone marrow tissue and by immunohistochemistry in the ear skin, before treatment, just after treatment, and 4 months later. The LCP+Allop and LC+Allop groups, but not the Allop group, showed significant suppression of the parasites in the liver, spleen, and bone marrow 4 months after treatment compared to the pretreatment period or the control group. Only LCP+Allop group showed significantly lower parasite burden in the skin in comparison to the control group. On the basis of clinical staging and parasitological evaluations, the LCP formulation exhibited a more favorable therapeutic profile than the LC one, being therefore promising for the treatment of canine visceral leishmaniasis.


Assuntos
Antiprotozoários , Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Compostos Organometálicos , Alopurinol/uso terapêutico , Animais , Antiprotozoários/uso terapêutico , Doenças do Cão/tratamento farmacológico , Cães , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/veterinária , Lipossomos/uso terapêutico , Meglumina/uso terapêutico , Antimoniato de Meglumina/uso terapêutico , Compostos Organometálicos/uso terapêutico , Polietilenoglicóis/uso terapêutico
19.
Nanomedicine (Lond) ; 15(8): 755-771, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32193975

RESUMO

Aim: To investigate the photodynamic therapeutic potential of ferromagnetic iron oxide nanorods (FIONs), using Trigonella foenum-graecum as a reducing agent, against Leishmania tropica. Materials & methods: FIONs were characterized using ultraviolet visible spectroscopy, x-ray diffraction and scanning electron microscopy. Results: FIONs showed excellent activity against L. tropica promastigotes and amastigotes (IC50 0.036 ± 0.003 and 0.072 ± 0.001 µg/ml, respectively) upon 15 min pre-incubation light-emitting diode light (84 lm/W) exposure, resulting in reactive oxygen species generation and induction of cell death via apoptosis. FIONs were found to be highly biocompatible with human erythrocytes (LD50 779 ± 21 µg/ml) and significantly selective (selectivity index >1000) against murine peritoneal macrophages (CC50 102.7 ± 2.9 µg/ml). Conclusion: Due to their noteworthy in vitro antileishmanial properties, FIONs should be further investigated in an in vivo model of the disease.


Assuntos
Antiprotozoários , Compostos Férricos , Leishmania tropica/efeitos dos fármacos , Nanotubos , Espécies Reativas de Oxigênio/metabolismo , Animais , Antiprotozoários/farmacologia , Eritrócitos , Humanos , Macrófagos , Camundongos , Camundongos Endogâmicos BALB C
20.
J Nat Prod ; 82(12): 3208-3220, 2019 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-31815454

RESUMO

The physicochemical characteristics of nanostructured suspensions are important prerequisites for the success of new drug development. This work aimed to develop nanometric systems containing Cymbopogon densiflorus leaf essential oil and to evaluate their antimicrobial activity. The essential oil was isolated by hydrodistillation from leaves and analyzed by GC-MS. The main constituents were found to be trans-p-mentha-2,8-dien-1-ol, cis-p-mentha-2,8-dien-1-ol, trans-p-mentha-1(7),8-dien-2-ol, cis-piperitol, and cis-p-mentha-1(7),8-dien-2-ol. In silico prediction analysis suggested that this oil possesses antimicrobial potential and the main mechanism of action might be the peptidoglycan glycosyltransferase inhibition. Nanoemulsions were prepared by the phase inversion method, and liposomes were made by the film hydration method. Qualitative evaluation of the antimicrobial activity was performed by the diffusion disk assay with 24 microorganisms; all of them were found to be sensitive to the essential oil. Subsequently, this property was quantified by the serial microdilution technique, where the nanoformulations demonstrated improved activity in comparison with the free oil. Bactericidal action was tested by the propidium iodide method, which revealed that free essential oil and nanoemulsion increased cytoplasmic membrane permeability, while no difference was observed between negative control and liposome. These results were confirmed by images obtained using transmission electron microscopy. This study has shown an optimization in the antimicrobial activity of C. densiflorus essential oil by a nanoemulsion and a liposomal formulation of the active substances.


Assuntos
Anti-Infecciosos/farmacologia , Cymbopogon/química , Nanoestruturas , Óleos Voláteis/farmacologia , Folhas de Planta/química , Animais , Anti-Infecciosos/química , Bactérias/efeitos dos fármacos , Linhagem Celular , Permeabilidade da Membrana Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fungos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Camundongos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Óleos Voláteis/química , Tamanho da Partícula , Relação Quantitativa Estrutura-Atividade
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