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1.
Int J Mol Sci ; 25(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38673856

RESUMEN

Immune response to biomaterials, which is intimately related to their surface properties, can produce chronic inflammation and fibrosis, leading to implant failure. This study investigated the development of magnetic nanoparticles coated with silica and incorporating the anti-inflammatory drug naproxen, aimed at multifunctional biomedical applications. The synthesized nanoparticles were characterized using various techniques that confirmed the presence of magnetite and the formation of a silica-rich bioactive glass (BG) layer. In vitro studies demonstrated that the nanoparticles exhibited bioactive properties, forming an apatite surface layer when immersed in simulated body fluid, and biocompatibility with bone cells, with good viability and alkaline phosphatase activity. Naproxen, either free or encapsulated, reduced nitric oxide production, an inflammatory marker, while the BG coating alone did not show anti-inflammatory effects in this study. Overall, the magnetic nanoparticles coated with BG and naproxen showed promise for biomedical applications, especially anti-inflammatory activity in macrophages and in the bone field, due to their biocompatibility, bioactivity, and osteogenic potential.


Asunto(s)
Materiales Biocompatibles Revestidos , Vidrio , Nanopartículas de Magnetita , Naproxeno , Naproxeno/farmacología , Naproxeno/química , Vidrio/química , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Nanopartículas de Magnetita/química , Animales , Ratones , Humanos , Óxido Nítrico/metabolismo , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Dióxido de Silicio/química , Supervivencia Celular/efectos de los fármacos , Células RAW 264.7 , Osteogénesis/efectos de los fármacos
2.
Int J Mol Sci ; 24(6)2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36982196

RESUMEN

Many activities have been described for propolis, including, antiviral, antibacterial, antifungal, anti-inflammatory, immunoregulatory, antioxidant and wound healing properties. Recently, propolis has been highlighted due to its potential application in the pharmaceutical and cosmetic industries, motivating a better understanding of its antioxidant and anti-inflammatory activities. Propolis and its main polyphenolic compounds presented high antioxidant activity, and effectiveness as broad spectrum UVB and UVA photoprotection sunscreens. Through a qualitative phytochemical screening, the ethanolic red propolis extracts (EEPV) (70% at room temperature and 70% at a hot temperature) presented a positive result for flavonoids and terpenoids. It presented an antioxidant activity for reducing 50% of DPPH of 17 and 12 µg/mL for extraction at room temperature and at a hot temperature, respectively. The UPLC-QTOF-MS/MS analysis allowed the annotation of 40 substances for EEPV-Heated and 42 substances for EEPV-Room Temperature. The IC50 results of the ABTS scavenging activity was 4.7 µg/mL for both extractions, at room temperature and at a hot temperature. Additionally, we also evaluated the cytotoxic profile of propolis extracts against macrophage (RAW 264.7 cells) and keratinocytes (HaCaT cells), which showed non-cytotoxic doses in cell viability assays even after a long period of exposure. In addition, propolis extracts showed antibacterial activity for Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis), demonstrating potential biological activity for the creation of formulations aimed at disease control and prevention.


Asunto(s)
Antiinfecciosos , Ascomicetos , Própolis , Própolis/farmacología , Própolis/química , Antioxidantes/farmacología , Antioxidantes/química , Protectores Solares/farmacología , Espectrometría de Masas en Tándem , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinflamatorios/uso terapéutico , Extractos Vegetales/farmacología , Extractos Vegetales/química
3.
Molecules ; 28(23)2023 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-38067542

RESUMEN

Chagas disease (CD) is a worldwide public health problem, and the drugs available for its treatment have severe limitations. Red propolis is a natural extract known for its high content of phenolic compounds and for having activity against T. cruzi. The aim of this study was to investigate the trypanocidal potential of red propolis to isolate, identify, and indicate the mode of action of the bioactive compounds. The results revealed that the total phenolic content was 15.4 mg GAE/g, and flavonoids were 7.2 mg QE/g. The extract was fractionated through liquid-liquid partitioning, and the trypanocidal potential of the samples was evaluated using the epimastigote forms of the Y strain of T. cruzi. In this process, one compound was characterized by MS, 1H, and 13C NMR and identified as vestitol. Cytotoxicity was evaluated employing MRC-5 fibroblasts and H9C2 cardiomyocytes, showing cytotoxic concentrations above 15.62 µg/mL and 31.25 µg/mL, respectively. In silico analyses were applied, and the data suggested that the substance had a membrane-permeation-enhancing effect, which was confirmed through an in vitro assay. Finally, a molecular docking analysis revealed a higher affinity of vestitol with farnesyl diphosphate synthase (FPPS). The identified isoflavan appears to be a promising lead compound for further development to treat Chagas disease.


Asunto(s)
Enfermedad de Chagas , Própolis , Tripanocidas , Trypanosoma cruzi , Humanos , Própolis/química , Simulación del Acoplamiento Molecular , Enfermedad de Chagas/tratamiento farmacológico , Flavonoides/química , Extractos Vegetales/farmacología , Tripanocidas/química
4.
Int J Mol Sci ; 23(18)2022 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-36142698

RESUMEN

Modified release systems depend on the selection of an appropriate agent capable of controlling the release of the drug, sustaining the therapeutic action over time, and/or releasing the drug at the level of a particular tissue or target organ. Polyethylene glycol 4000 (PEG 4000) is commonly employed in drug release formulations while polymethyl methacrylate (PMMA) is non-toxic and has a good solubility in organic solvents. This study aimed at the incorporation of ketoconazole in PMMA-g-PEG 4000 and its derivatives, thus evaluating its release profile and anti-Candida albicans and cytotoxic activities. Ketoconazole was characterized and incorporated into the copolymers. The ketoconazole incorporated in the copolymer and its derivatives showed an immediate release profile. All copolymers with ketoconazole showed activity against Candida albicans and were non-toxic to human cells in the entire concentration tested.


Asunto(s)
Candida albicans , Cetoconazol , Antifúngicos/farmacología , Humanos , Cetoconazol/farmacología , Polietilenglicoles , Polimetil Metacrilato , Solventes
5.
Artículo en Inglés | MEDLINE | ID: mdl-33168611

RESUMEN

Chronic Chagas disease might have an impact on benznidazole pharmacokinetics with potential alterations in the therapeutic dosing regimen. This study aims to investigate the influence of chronic Trypanosoma cruzi infection on the pharmacokinetics and biodistribution of benznidazole in mice. Healthy (n = 40) and chronically T. cruzi (Berenice-78 strain)-infected (n = 40) Swiss female 10-month-old mice received a single oral dose of 100 mg/kg of body weight of benznidazole. Serial blood, heart, colon, and brain samples were collected up to 12 h after benznidazole administration. The serum and tissue samples were analyzed using a high-performance liquid chromatography instrument coupled to a diode array detector. Chronic infection by T. cruzi increased the values of the pharmacokinetic parameters absorption rate constant (Ka ) (3.92 versus 1.82 h-1), apparent volume of distribution (V/F) (0.089 versus 0.036 liters), and apparent clearance (CL/F) (0.030 versus 0.011 liters/h) and reduced the values of the time to the maximum concentration of drug in serum (Tmax) (0.67 versus 1.17 h) and absorption half-life (t1/2a ) (0.18 versus 0.38 h). Tissue exposure (area under the concentration-versus-time curve from 0 h to time t for tissue [AUC0-t,tissue]) was longer and higher in the colon (8.15 versus 21.21 µg · h/g) and heart (5.72 versus 13.58 µg · h/g) of chronically infected mice. Chronic infection also increased the benznidazole tissue penetration ratios (AUC0-t,tissue/AUC0-t,serum ratios) of brain, colon, and heart by 1.6-, 3.25-, and 3-fold, respectively. The experimental chronic Chagas disease inflammation-mediated changes in the regulation of membrane transporters probably influence the benznidazole pharmacokinetics and the extent of benznidazole exposure in tissues. These results advise for potential alterations in benznidazole pharmacokinetics in chronic Chagas disease patients with possibilities of changes in the standard dosing regimen.


Asunto(s)
Enfermedad de Chagas , Nitroimidazoles , Tripanocidas , Trypanosoma cruzi , Animales , Enfermedad de Chagas/tratamiento farmacológico , Femenino , Humanos , Ratones , Nitroimidazoles/uso terapéutico , Distribución Tisular , Tripanocidas/uso terapéutico
6.
Cytokine ; 136: 155255, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32866897

RESUMEN

Distinct populations of Trypanosoma cruzi interact with mammalian cardiac muscle cells causing different inflammation patterns and low heart functionality. During T. cruzi infection, the extracellular ATP is hydrolyzed to tri- and/or diphosphate nucleotides, based on the infectivity, virulence, and regulation of the inflammatory response. T. cruzi carries out this hydrolysis through the T. cruzi ectonucleotidase, NTPDase-1 (TcNTPDase-1). This study aimed to evaluate the role of TcNTPDase-1 in culture rich in metacyclic trypomastigote forms (MT) and cell culture-derived trypomastigote forms (CT) from Colombiana (discrete typing unit - DTU I), VL-10 (DTU II), and CL (DTU VI) strains of T. cruzi. For this, we measured TcNTPDase-1 activity in suramin-treated and untreated parasites and infected J774 cells and C57BL/6 mice with suramin pre-treated parasites to assess parasitic and inflammatory cardiac profile in the acute phase of infection. Our data indicated a higher TcNTPDase-1 activity for ATP in culture rich in metacyclic trypomastigote forms from Colombiana strain in comparison to those from VL-10 and CL strains. The cell culture-derived trypomastigote forms from CL strain presented higher capacity to hydrolyze ATP than those from Colombiana and VL-10 strains. Suramin inhibited ATP hydrolysis in all studied parasite forms and strains. Suramin pre-treated parasites reduced J774 cell infection and increased nitrite production in vitro. In vivo studies showed a reduction of inflammatory infiltrate in the cardiac tissues of animals infected with cell culture-derived trypomastigote forms from suramin pre-treated Colombiana strain. In conclusion, TcNTPDase-1 activity in trypomastigotes forms drives part of the biological characteristics observed in distinct DTUs and may induce cardiac pathogenesis during T. cruzi infection.


Asunto(s)
Antígenos CD , Apirasa , Enfermedad de Chagas , Proteínas Protozoarias , Trypanosoma cruzi , Factores de Virulencia , Animales , Antígenos CD/genética , Antígenos CD/metabolismo , Apirasa/genética , Apirasa/metabolismo , Línea Celular Tumoral , Enfermedad de Chagas/enzimología , Enfermedad de Chagas/genética , Ratones , Ratones Endogámicos BALB C , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Especificidad de la Especie , Trypanosoma cruzi/enzimología , Trypanosoma cruzi/genética , Trypanosoma cruzi/patogenicidad , Factores de Virulencia/genética , Factores de Virulencia/metabolismo
7.
Exp Parasitol ; 218: 108012, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33011239

RESUMEN

Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in almost all countries of Latin America. In Brazil, oral infection is becoming the most important mechanism of transmission of the disease in several regions of the country. The gastrointestinal tract is the gateway for the parasite through this route of infection, however, little is known about the involvement of these organs related to oral route. In this sense, the present study evaluated the impact of oral infection on the digestive tract in mice infected by Berenice-78 (Be-78) T. cruzi strain, in comparison with the intraperitoneal route of infection. In this work, the intraperitoneal route group showed a peak of parasitemia similar to the oral route group, however the mortality rate among the orally infected animals was higher when compared to intraperitoneal route. By analyzing the frequency of blood cell populations, differences were mainly observed in CD4+ T lymphocytes, and not in CD8+, presenting an earlier reduction in the number of CD4+ T cells, which persisted for a longer period, in the animals of the oral group when compared with the intraperitoneal group. Animals infected by oral route presented a higher tissue parasitism and inflammatory infiltrate in stomach, duodenum and colon on the 28th day after infection. Therefore, these data suggest that oral infection has a different profile of parasitological and immune responses compared to intraperitoneal route, being the oral route more virulent and with greater tissue parasitism in organs of the gastrointestinal tract evaluated during the acute phase.


Asunto(s)
Enfermedad de Chagas/patología , Tracto Gastrointestinal/patología , Tracto Gastrointestinal/parasitología , Trypanosoma cruzi/patogenicidad , Administración Oral , Análisis de Varianza , Animales , Enfermedad de Chagas/mortalidad , Enfermedad de Chagas/parasitología , Colon/parasitología , Colon/patología , Duodeno/parasitología , Duodeno/patología , Inmunofenotipificación , Masculino , Ratones , Monocitos/patología , Parasitemia/mortalidad , Parasitemia/parasitología , Estómago/parasitología , Estómago/patología , Tasa de Supervivencia
8.
Exp Parasitol ; 210: 107834, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31978394

RESUMEN

Studies suggest that the dose of the standard benznidazole (BNZ) treatment regimen might be too high. We investigated the efficacy of BNZ 20 and 40 mg/kg/day compared with standard dose (100 mg/kg/day) to induce cure in mice infected with Trypanosoma cruzi Y strain in the acute and chronic phases of Chagas' disease. Our findings indicate that an experimental treatment with a BNZ low-dose (40 mg/kg/day) is similarly effective as the usual dose in the chronic mice model (100% of cure). In addition, the treatment in the chronic model of Chagas' disease presented better results than the acute model and colon appears to be a key tissue when it comes to evaluating treatment efficacy compared to blood and heart. Therefore, our data suggest the reconsideration of the current therapy, mainly in the chronic phase of the disease.


Asunto(s)
Enfermedad de Chagas/tratamiento farmacológico , Nitroimidazoles/administración & dosificación , Tripanocidas/administración & dosificación , Enfermedad Aguda , Animales , Sangre/parasitología , Enfermedad de Chagas/parasitología , Enfermedad Crónica , Colon/parasitología , Ciclofosfamida/administración & dosificación , Ciclofosfamida/farmacología , Ciclofosfamida/uso terapéutico , Femenino , Corazón/parasitología , Terapia de Inmunosupresión , Ratones , Enfermedades Desatendidas/tratamiento farmacológico , Enfermedades Desatendidas/parasitología , Nitroimidazoles/uso terapéutico , Reacción en Cadena en Tiempo Real de la Polimerasa , Tripanocidas/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Trypanosoma cruzi/genética , Trypanosoma cruzi/fisiología
9.
Parasitol Res ; 119(12): 4185-4195, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33033848

RESUMEN

Leishmania spp. parasites have a complex biological cycle presenting basically two different morphological stages, the amastigote and promastigote forms. In vitro cultivation allows a more complete study of the biological aspects of these parasites, indicating better conditions for infection, immunoassay tests, drug evaluations, and vaccines. Thus, we evaluated the three most used culture media for Leishmania spp., Grace's insect cell culture medium (Grace's), liver infusion tryptose (LIT), and Schneider's insect medium (Schneider's), without supplementation or supplemented with fetal calf serum (FCS) and bovine serum albumin (Albumin) to evaluate the growth, viability, and infectivity of the L. infantum promastigotes. It was observed that promastigote forms have a better growth in LIT and Schneider's with or without FCS when compared to that in Grace's. The supplementation with albumin promoted greater viability of the parasites independent of the medium. For in vitro infection of J774.A1 macrophages using light microscopy and flow cytometry analyses, FCS-supplemented LIT and Grace's promoted higher percentage of infected macrophages and parasite load compared with Schneider's media. Taken together, our results demonstrated that the supplementation of LIT culture medium with FCS is the most suitable strategy to cultivate Leishmania infantum parasites enabling the maintenance of growth and infective parasites for research uses.


Asunto(s)
Leishmania infantum/efectos de los fármacos , Leishmania infantum/crecimiento & desarrollo , Hígado/enzimología , Parasitología/métodos , Animales , Células Cultivadas , Medios de Cultivo/química , Medios de Cultivo/farmacología , Leishmania infantum/fisiología , Estadios del Ciclo de Vida/efectos de los fármacos , Macrófagos/parasitología , Ratones , Compuestos Orgánicos/análisis , Compuestos Orgánicos/farmacología
10.
Phytother Res ; 34(1): 94-103, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31713305

RESUMEN

The research for new treatments of skin and soft tissue infections (SSTIs) is important due to their high prevalence and number of hospitalizations. The purpose of this review is to address the pathophysiology of SSTIs to highlight the advantages of herbal medicines to their treatment, showing examples of species and compounds with multi-targets action. SSTIs have a complex physiopathology involving the microorganism, as well as inflammation and difficult healing. Therefore, antimicrobial, anti-inflammatory, antioxidant and healing activities are an approach possible for their treatment. Herbal medicines have a wide diversity of biological compounds, mainly phenolic compounds that may act on different targets and also have synergism between them. Therefore, a single medicine may have the four key activities that allied allow eliminating the infection, control the inflammation process and accelerating the healing process, preventing complications with chronic infections.


Asunto(s)
Medicina de Hierbas/métodos , Plantas Medicinales/química , Enfermedades de la Piel/tratamiento farmacológico , Infecciones de los Tejidos Blandos/tratamiento farmacológico , Humanos
11.
Mem Inst Oswaldo Cruz ; 113(11): e180271, 2018 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-30365644

RESUMEN

BACKGROUND The infection led by Trypanosoma cruzi persists in mammalian tissues causing an inflammatory imbalance. Carvedilol (Cv), a non-selective beta blocker drug indicated to treat heart failure and antihypertensive has shown to promote antioxidant and immunomodulatory properties which might improve the inflammation induced by T. cruzi. OBJECTIVES Evaluate the role of Cv on the inflammatory response of C57BL/6 mice acutely infected with the Colombian strain of T. cruzi. METHODS Animals were infected with the Colombian strain of T. cruzi and treated with Cv (25 mg/kg/day), benznidazole (Bz) (100 mg/kg/day) or their combination. On the 28th day of infection and 23 days of treatment, the euthanasia occurred, and the heart preserved for histopathological, oxidative stress (SOD, catalase, TBARs, carbonylated proteins) and plasma (CCL2, CCL5, TNF, IL-10) analyses. Parasitaemia and survival were assessed along the infection. FINDINGS Cv decreased TBARs, but increased the mortality rate, the parasitaemia and the levels of CCL2, CCL5, catalase and the inflammatory infiltrate in the cardiac tissue. Bz led the reduction of the inflammatory infiltrate and circulating levels of oxidative stress and inflammatory mediators in the infected mice. MAIN CONCLUSIONS Our data suggest that Cv, in this experimental model using the Colombian strain of T. cruzi, caused damage to the host.


Asunto(s)
Antagonistas Adrenérgicos beta/farmacología , Carvedilol/farmacología , Enfermedad de Chagas/tratamiento farmacológico , Corazón/efectos de los fármacos , Nitroimidazoles/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Enfermedad Aguda , Animales , Catalasa/análisis , Enfermedad de Chagas/parasitología , Enfermedad de Chagas/patología , Citocinas/sangre , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Masculino , Ratones Endogámicos C57BL , Miocardio/patología , Estrés Oxidativo/efectos de los fármacos , Parasitemia/parasitología , Carbonilación Proteica/efectos de los fármacos , Valores de Referencia , Reproducibilidad de los Resultados , Superóxido Dismutasa/análisis , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Factores de Tiempo , Trypanosoma cruzi/aislamiento & purificación
12.
Artículo en Inglés | MEDLINE | ID: mdl-28167558

RESUMEN

Specific chemotherapy using benznidazole (BNZ) for Chagas disease during the chronic stage is controversial due to its limited efficacy and toxic effects. Although BNZ has been used to treat Chagas disease since the 1970s, few studies about the biodistribution of this drug exist. In this study, BNZ tissue biodistribution in a murine model and its pharmacokinetic profile in plasma were monitored. A bioanalytical high-performance liquid chromatography method with a UV detector (HPLC-UV) was developed and validated according to the European Medicines Agency for quantification of BNZ in organs and plasma samples prepared by liquid-liquid extraction using ethyl acetate. The developed method was linear in the BNZ concentration, which ranged from 0.1 to 100.0 µg/ml for plasma, spleen, brain, colon, heart, lung, and kidney and from 0.2 to 100.0 µg/ml for liver. Validation assays demonstrated good stability for BNZ under all conditions evaluated. Pharmacokinetic parameters confirmed rapid, but low, absorption of BNZ after oral administration. Biodistribution assays demonstrated different maximum concentrations in organs and similar times to maximum concentration and mean residence times, with means of 40 min and 2.5 h, respectively. Therefore, the biodistribution of BNZ is extensive, reaching organs such as the heart and colon, which are the most relevant organs affected by Trypanosoma cruzi infection, and also the spleen, brain, liver, lungs, and kidneys. Simultaneous analyses of tissues and plasma indicated high BNZ metabolism in the liver. Our results suggest that low bioavailability, instead of inadequate biodistribution, could be responsible for therapeutic failure during the chronic phase of Chagas disease.


Asunto(s)
Nitroimidazoles/sangre , Tripanocidas/sangre , Administración Oral , Adolescente , Adulto , Animales , Enfermedad de Chagas/sangre , Enfermedad de Chagas/tratamiento farmacológico , Cromatografía Líquida de Alta Presión , Femenino , Humanos , Masculino , Ratones , Nitroimidazoles/farmacocinética , Nitroimidazoles/uso terapéutico , Tripanocidas/farmacocinética , Tripanocidas/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Trypanosoma cruzi/patogenicidad , Adulto Joven
13.
Mem Inst Oswaldo Cruz ; 109(1): 51-60, 2014 02.
Artículo en Inglés | MEDLINE | ID: mdl-24271001

RESUMEN

Chagasic megaoesophagus and megacolon are characterised by motor abnormalities related to enteric nervous system lesions and their development seems to be related to geographic distribution of distinct Trypanosoma cruzi subpopulations. Beagle dogs were infected with Y or Berenice-78 (Be-78) T. cruzi strains and necropsied during the acute or chronic phase of experimental disease for post mortem histopathological evaluation of the oesophagus and colon. Both strains infected the oesophagus and colon and caused an inflammatory response during the acute phase. In the chronic phase, inflammatory process was observed exclusively in the Be-78 infected animals, possibly due to a parasitism persistent only in this group. Myenteric denervation occurred during the acute phase of infection for both strains, but persisted chronically only in Be-78 infected animals. Glial cell involvement occurred earlier in animals infected with the Y strain, while animals infected with the Be-78 strain showed reduced glial fibrillary acidic protein immunoreactive area of enteric glial cells in the chronic phase. These results suggest that although both strains cause lesions in the digestive tract, the Y strain is associated with early control of the lesion, while the Be-78 strain results in progressive gut lesions in this model.


Asunto(s)
Enfermedad de Chagas/parasitología , Colon/parasitología , Modelos Animales de Enfermedad , Esófago/parasitología , Plexo Mientérico/parasitología , Trypanosoma cruzi/clasificación , Reacción de Fase Aguda/parasitología , Animales , Autopsia , Enfermedad de Chagas/patología , Enfermedad Crónica , Colitis/parasitología , Colon/patología , Progresión de la Enfermedad , Perros , Acalasia del Esófago/parasitología , Esofagitis/parasitología , Esófago/patología , Megacolon/parasitología , Especificidad de la Especie
14.
Mem Inst Oswaldo Cruz ; 109(8): 1005-13, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25591108

RESUMEN

Trypanosoma cruzi infection may be caused by different strains with distinct discrete typing units (DTUs) that can result in variable clinical forms of chronic Chagas disease. The present study evaluates the immune response and cardiac lesions in dogs experimentally infected with different T. cruzi strains with distinct DTUs, namely, the Colombian (Col) and Y strains of TcI and TcII DTU, respectively. During infection with the Col strain, increased levels of alanine aminotransferase, erythrocytes, haematocrit and haemoglobin were observed. In addition, CD8+ T-lymphocytes isolated from the peripheral blood produced higher levels of interleukin (IL)-4. The latter suggests that during the acute phase, infection with the Col strain may remain unnoticed by circulating mononuclear cells. In the chronic phase, a significant increase in the number of inflammatory cells was detected in the right atrium. Conversely, infection with the Y strain led to leucopoenia, thrombopoenia, inversion of the ratio of CD4+/CD8+ T-lymphocytes and alterations in monocyte number. The Y strain stimulated the production of interferon-γ by CD4+ and CD8+ T-lymphocytes and IL-4 by CD8+ T-cells. In the chronic phase, significant heart inflammation and fibrosis were observed, demonstrating that strains of different DTUs interact differently with the host.


Asunto(s)
Enfermedad de Chagas/inmunología , Miocardio/patología , Trypanosoma cruzi/inmunología , Alanina Transaminasa/sangre , Animales , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/metabolismo , Enfermedad de Chagas/sangre , Enfermedad de Chagas/patología , Enfermedad Crónica , Modelos Animales de Enfermedad , Perros , Recuento de Eritrocitos , Fibrosis/inmunología , Fibrosis/parasitología , Citometría de Flujo , Hematócrito , Hemoglobinas/análisis , Interleucina-4/metabolismo , Leucocitos Mononucleares/química , Recuento de Linfocitos , Miocardio/química , Miocardio/inmunología , Fenotipo , Trypanosoma cruzi/metabolismo
15.
Pharmaceutics ; 16(6)2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38931921

RESUMEN

Chagas disease (CD) is a worldwide public health problem. Benznidazole (BZ) is the drug used to treat it. However, in its commercial formulation, it has significant side effects and is less effective in the chronic phase of the infection. The development of particulate systems containing BZ is therefore being promoted. The objective of this investigation was to develop polymeric nanoparticles loaded with BZ and examine their trypanocidal impact in vitro. Two formulas (BNP1 and BNP2) were produced through double emulsification and freeze drying. Subsequent to physicochemical and morphological assessment, both formulations exhibited adequate yield, average particle diameter, and zeta potential for oral administration. Cell viability was assessed in H9C2 and RAW 264.7 cells in vitro, revealing no cytotoxicity in cardiomyocytes or detrimental effects in macrophages at specific concentrations. BNP1 and BNP2 enhanced the effect of BZ within 48 h using a treatment of 3.90 µg/mL. The formulations notably improved NO reduction, particularly BNP2. The findings imply that the compositions are suitable for preclinical research, underscoring their potential as substitutes for treating CD. This study aids the quest for new BZ formulations, which are essential in light of the disregard for the treatment of CD and the unfavorable effects associated with its commercial product.

16.
Pharmaceutics ; 16(6)2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38931824

RESUMEN

The treatment of skin and soft tissue infections (SSTIs) can be challenging due to bacterial resistance, particularly from strains like MRSA and biofilm formation. However, combining conventional antibiotics with natural products shows promise in treating SSTIs. The objective of this study is to develop a nanoemulsion-based hydrogel containing Protium spruceanum extract and mupirocin and evaluate its potential for the treatment of SSTIs. The nanoemulsion was obtained by phase inversion and subsequently characterized. The antibacterial activity was evaluated in vitro against S. aureus MRSA, including the synergism of the combination, changes in membrane permeability using flow cytometry, and the anti-biofilm effect. In addition, the irritative potential was evaluated by the HET-CAM assay. The combination exhibited synergistic antibacterial activity against S. aureus and MRSA due to the extract enhancing membrane permeability. The hydrogel demonstrated suitable physicochemical properties, inhibited biofilm formation, and exhibited low irritation. The formulation was nanometric (176.0 ± 1.656 nm) and monodisperse (polydispersity index 0.286 ± 0.011). It exhibited a controlled release profile at 48 h and high encapsulation efficacy (94.29 ± 4.54% for quercitrin and 94.20 ± 5.44% for mupirocin). Therefore, these findings suggest that the hydrogel developed could be a safe and effective option for treating SSTIs.

17.
Pharmaceuticals (Basel) ; 17(6)2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38931388

RESUMEN

Melanoma, primarily caused by solar ultraviolet (UV) radiation, can be prevented by the use of sunscreens. However, the use of synthetic sunscreens raises environmental concerns. Natural compounds with antioxidant photoprotective properties and cytotoxic effects against cancer cells can be promising for the prevention and treatment of melanoma with less environmental effect. This study focuses on Melaleuca leucadendron essential oil (EO) for photoprotection and antitumor applications. EO was hydrodistilled from M. leucadendron leaves with a 0.59% yield. Gas chromatography-mass spectrometry detected monoterpenes and sesquiterpenes. Nanoemulsions were prepared with (NE-EO) and without EO (NE-B) using the phase inversion method, showing good stability, spherical or oval morphology, and a pseudoplastic profile. Photoprotective activity assessed spectrophotometrically showed that the NE-EO was more effective than NE-B and free EO. Antioxidant activity evaluated by DPPH and ABTS methods indicated that pure and nanoemulsified EO mainly inhibited the ABTS radical, showing IC50 40.72 and 5.30 µg/mL, respectively. Cytotoxicity tests on L-929 mouse fibroblasts, NGM human melanocyte, B16-F10 melanoma, and MeWo human melanoma revealed that EO and NE-EO were more cytotoxic to melanoma cells than to non-tumor cells. The stable NE-EO demonstrates potential for melanoma prevention and treatment. Further research is required to gain a better understanding of these activities.

18.
Vaccines (Basel) ; 11(2)2023 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-36851272

RESUMEN

BACKGROUND: The adjuvants' optimal dose and the administration route can directly influence the epitope recognition patterns and profiles of innate response. We aimed to establish the effect and the optimal dose of adjuvant systems for proposing a vaccine candidate to be employed with Leishmania (Viannia) braziliensis. METHODS: We evaluated the adjuvants saponin (SAP), monophosphoryl lipid A (MPL) and resiquimod (R-848) isolated and combined as adjuvant systems in a lower dose corresponding to 25%, 33%, and 50% of each adjuvant total dose. Male outbred BALB/c mice were divided into 13 groups, SAP, MPL, and R-848 isolated, and the adjuvant systems SAP plus MPL (SM), SAP plus R-848 (SR), and MPL plus R-848 (MR). RESULTS: SM50 increased levels of all chemokines analyzed and TNF production, while it presented an increased inflammatory cell infiltrate in the skin with macrophage recruitment. Thus, we proposed a vaccine candidate employing L. (V.) braziliensis antigen associated with the SM adjuvant system against experimental L. (Leishmania) infantum challenge. We observed a significant increase in the frequency of cells expressing the central and effector memory CD4+ T cells phenotype in immunized mice with the LBSM50. In the liver, there was a decreased parasite load when mice received LBSM50. CONCLUSIONS: When combined with L. (V.) braziliensis antigen, SM50 increases TNF and IFN-γ, which generates central and effector memory CD4+ T cells. Therefore, using an adjuvant system can promote an effective innate immune response with the potential to compose future vaccines.

19.
Arch Physiol Biochem ; : 1-15, 2022 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-36328030

RESUMEN

CONTEXT: The role of silymarin in hepatic lipid dysfunction and its possible mechanisms of action were investigated. OBJECTIVE: To evaluate the effects of silymarin on hepatic and metabolic profiles in mice fed with 30% fructose for 8 weeks. METHODS: We evaluated the antioxidant profile of silymarin; mice consumed 30% fructose and were treated with silymarin (120 mg/kg/day or 240 mg/kg/day). We performed biochemical, redox status, and histopathological assays. RT-qPCR was performed to detect ACC-1, ACC-2, FAS, and CS expression, and western blotting to detect PGC-1α levels. RESULTS: Silymarin contains high levels of phenolic compounds and flavonoids and exhibited significant antioxidant capacity in vitro. In vivo, the fructose-fed groups showed increased levels of AST, ALT, SOD/CAT, TBARS, hepatic TG, and cholesterol, as well as hypertriglyceridaemia, hypercholesterolaemia, and increased ACC-1 and FAS. Silymarin treatment reduced these parameters and increased mRNA levels and activity of hepatic citrate synthase. CONCLUSIONS: These results suggest that silymarin reduces worsening of NAFLD.

20.
Pathogens ; 10(6)2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34207764

RESUMEN

As the development of new drugs for Chagas disease is not a priority due to its neglected disease status, an option for increasing treatment adherence is to explore alternative treatment regimens, which may decrease the incidence of side effects. Therefore, we evaluated the efficacy of different therapeutic schemes with benznidazole (BNZ) on the acute and chronic phases of the disease, using mice infected with strains that have different BNZ susceptibilities. Our results show that the groups of animals infected by VL-10 strain, when treated in the chronic phase with a lower dose of BNZ for a longer period of time (40 mg/kg/day for 40 days) presented better treatment efficacy than with the standard protocol (100 mg/kg/day for 20 days) although the best result in the treatment of the animals infected by the VL-10 strain was with100 mg/kg/day for 40 days. In the acute infection by the Y and VL-10 strains of T. cruzi, the treatment with a standard dose, but with a longer time of treatment (100 mg/kg/day for 40 days) presented the best results. Given these data, our results indicate that for BNZ, the theory of dose and time proportionality does not apply to the phases of infection.

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