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1.
Cytokine ; 99: 80-90, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28738234

RESUMO

Leishmaniasis is a term referring to a range of clinical conditions caused by protozoan parasites of the genus Leishmania, Trypanosomatidae family, Kinetoplastida order that is transmitted by the bite of certain species of mosquitoes Phlebotominae subfamily. These parasites infect hosts wild and domestic mammals, considered as natural reservoirs and can also infect humans. Leishmania are obligate intramacrophage protozoa that have exclusively intracellular life style. This suggests that the amastigotes possess mechanisms to avoid killing by host cells. Cutaneous leishmaniasis, the most common form of the disease, causes ulcers on exposed parts of the body, leading to disfigurement, permanent scars, and stigma and in some cases disability. Many studies concluded that the cytokines profile and immune system of host have fundamental role in humans and animals natural self-healing. Conventional treatments are far from ideals and the search for new therapeutic alternatives is considered a strategic priority line of research by the World Health Organization. A promising approach in the field of basic research in homeopathy is the treatment of experimental infections with homeopathic drugs prepared from natural substances associations highly diluted, which comprise a combination of several different compounds considered as useful for a symptom or disease. Therefore, this study aimed to evaluate the effect of M1, a complex homeopathic product, in macrophage-Leishmania interaction in vitro and in vivo. It was used RAW cells lineage and BALB/c mice as a host for the promastigotes of L. amazonensis (WHOM/BR/75/Josefa). Several biochemical and morphological parameters were determined. Together, the harmonic results obtained in this study indicate that, in general, the highly diluted products trigger rapid and effective responses by living organisms, cells and mice, against Leishmania, by altering cytokines profile, by NO increasing (p<0.05), by decreasing parasitic load (p<0.001), and modifying classical maturation and biogenesis of parasitophorous vacuoles (p<0.001). M1 complex decreased endocytic index (p<0.001), and the % of infected macrophages (p<0.05), preventing the development of lesions (p<0.05) caused by L. amazonensis by increasing Th1 response (p<0.05). Therefore the M1complex can be a good candidate for a complementary therapy to conventional treatments, since all the parameters observed in vitro and in vivo improved. It could be an interesting clinical tool in association to a classical anti-parasitic treatment, maybe resulting in better quality of life to the patients, with less toxicity.


Assuntos
Homeopatia , Leishmania/fisiologia , Animais , Bioensaio , Citocinas/metabolismo , Peróxido de Hidrogênio/metabolismo , Leishmania/ultraestrutura , Leishmaniose Cutânea/parasitologia , Leishmaniose Cutânea/patologia , Macrófagos/parasitologia , Macrófagos/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Carga Parasitária , Células RAW 264.7
2.
Cytokine ; 92: 33-47, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28092793

RESUMO

BACKGROUND: In previous results mice treated with high dilutions of antimony presented reduction of monocyte migration to the site of infection with increase in B lymphocytes population in the local lymph node. AIMS: To know the mechanisms involved, a series of in vitro studies was done, using co-cultures of macrophages (RAW 264.7) and Leishmania (L.) amazonensis treated with different dilutions of antimony (Antimonium crudum or AC), in different times. METHODOLOGY: Spreading, phagocytosis, the oxidative activity of macrophages, the viability of free promastigotes and the cytokines/chemokines concentration in the supernatant were evaluated. The assays were performed in quadruplicate. RESULTS: Cells treated with AC 30cH (10-58M) and AC 200cH (10-398M) presented a temporary reduction of the spreading after 02h of incubation, followed by increase after 48h, being the most significant increase observed after the AC 200cH treatment. However, the percentage of internalized parasites at 48, 96 and 120h of incubation was also higher in cells treated with AC 200cH. It is suggested that the AC 200cH improves the ability of phagocytes to internalize the parasites, but not to digest them. The cytokines-chemokines panel corroborated these results. Both dilutions potentiated the parasite-induced reduction of cytokines production, especially IL-6, IL 12 p40 and γ-IFN, after 48h of incubation. In addition, the production of MIP-1 beta (CCL4), a chemokine involved in chronic inflammation, was also reduced after 120h. A specific effect of AC 30cH was seen by the inhibition of two peaks of CCL2 (MCP-1) observed in infected macrophages, at 24 and 120h. Since this cytokine is an important chemokine for monocytes, it explains the results obtained formerly in vivo. The morphology of macrophages after acridine orange staining revealed that the treatment with AC 30cH reduced substantially the acid vacuoles in the cytoplasm, indicating a certain inability of these cells to digest the parasites. On the other hand, a large peak of VEGF-A, associated with increase of internalized parasites was observed after 120h of treatment with AC 200cH, which could be associated to the regulation of the chronic inflammation events by M1-M2 polarization. There was no statistical difference among groups regarding the production of TNF, NO and H2O2, showing that the drugs do not alter macrophage cytotoxic activity. A clear quantitative and qualitative variation of the modulatory effects of AC 30cH and 200cH was seen, in function of time. CONCLUSIONS: Both dilutions were able to potentiate the decrease of most of cytokines and chemokines induced by the parasite infection in vitro, which explains the clinical improvement seen previously in vivo, however, the mechanisms involved and the epidemiological significance of these findings are still under discussion.


Assuntos
Antimônio/farmacologia , Leishmania/imunologia , Leishmaniose/imunologia , Macrófagos/imunologia , Monocinas/imunologia , Animais , Leishmaniose/patologia , Macrófagos/parasitologia , Camundongos , Células RAW 264.7
3.
Microb Pathog ; 99: 14-18, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27427089

RESUMO

The A22 is a chemical compound that acts as a reversible inhibitor of a bacterial cell wall protein MreB leading the rods to the coccoid form. Thus, by changing the bacterial form, many properties can be affected, as the acquisition of nutrients, cell division, the clamping surfaces, motility and pathogenesis. Infections caused by strains of Pseudomonas aeruginosa have great clinical importance because these microorganisms can include more than one resistance mechanism acting together, limiting treatment options. Thus, it is important to investigate the action of A22 against P. aeruginosa, once there are urgent needs for new antimicrobial compounds for increase the arsenal therapeutic to treat diseases caused by this microrganism. Therefore, this study investigated for the first time the antimicrobial activity of A22 against seve standards strains of Gram negative microorganisms and twenty-eight clinical isolates of P. aeruginosa. This study performed an additional investigation to analyze the cyto and genotoxic potential effects from A22 on human peripheral blood mononuclear cells (PBMCs). The antibacterial activity of A22 was studied by broth microdilution method and time-kill assay. The cytotoxicity was evaluated by MTT assay at 24, 48 and 72 h of exposure to A22 and the genotoxicity was evaluated by the Comet assay. The susceptibility tests showed A22 has a relevant antibacterial activity against P. aeruginosa, including multidrug-resistant (MDR) clinical isolates. The A22 treatment not showed genotoxic effects against PBMCs in almost all concentrations tested at 24 and 48 h of exposure. Only for concentration of 32 µg/mL (highest tested) the damage index was significantly higher in all moments. The MTT assay demonstrated that A22 was able to maintain cell viability in all exposure times. In summary, the A22 demonstrated important anti-Pseudomonas activity and showed no cyto and genotoxic significant effect. These results need to be considered in future in vitro and in vivo studies in order to introduce the A22 as a possible therapeutic option.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/toxicidade , Bactérias Gram-Negativas/efeitos dos fármacos , Mutagênicos/toxicidade , Tioureia/análogos & derivados , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Formazans/análise , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos dos fármacos , Coloração e Rotulagem , Sais de Tetrazólio/análise , Tioureia/farmacologia , Tioureia/toxicidade , Fatores de Tempo
4.
Exp Parasitol ; 166: 144-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27109312

RESUMO

The aims of this study were to develop nerolidol-loaded nanospheres, and to evaluate their efficacy in vitro and in vivo against Trypanosoma evansi, as well as to determine their physicochemical properties, morphology, and any possible side effect in vitro against peripheral blood mononuclear cell (PBMC). The nanospheres showed an adequate particle size (149.5 nm), narrow particle distribution (0.117), negative zeta potential (-12.8 mV), and pH of 6.84, such as observed by transmission electron microscopy. In vitro, a trypanocidal effect of nerolidol and nanospheres containing nerolidol was observed at 0.5, 1.0, and 2.0%, i.e., both treatments showed a faster trypanocidal effect compared to chemotherapy (diminazene aceturate - D.A.). T. evansi infected mice were used to evaluate the effects of nerolidol-loaded nanospheres regarding pre-patent period, longevity, and therapeutic efficacy. Oral administration of nerolidol-loaded nanospheres at 1.0 mL/kg/day during 10 days increased mice survival (66.66%) compared to 0% and 33.33% of mice survival when treated with nerolidol in its free form and D.A., respectively. Cytotoxic study indicated that both treatments showed no side effects in vitro against PBMC, an important marker used in toxicological surveys. Therefore, nanoencapsulation increased the therapeutic efficacy of nerolidol against T. evansi, and can be used as an alternative treatment for T. evansi infection.


Assuntos
Diminazena/análogos & derivados , Sesquiterpenos/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma/efeitos dos fármacos , Administração Oral , Adulto , Animais , Criopreservação , Diminazena/farmacologia , Diminazena/toxicidade , Cães , Resistência a Medicamentos , Feminino , Humanos , Concentração de Íons de Hidrogênio , Leucócitos Mononucleares/efeitos dos fármacos , Camundongos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanosferas , Parasitemia/tratamento farmacológico , Parasitemia/parasitologia , Tamanho da Partícula , Ratos , Sesquiterpenos/administração & dosagem , Sesquiterpenos/toxicidade , Tripanossomicidas/administração & dosagem , Tripanossomicidas/toxicidade , Trypanosoma/ultraestrutura , Tripanossomíase/tratamento farmacológico , Tripanossomíase/parasitologia , Adulto Jovem
5.
Exp Parasitol ; 161: 12-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26704663

RESUMO

Trypanosoma evansi is an important pathogen that causes changes in nitric oxide (NO) levels and antioxidant enzymes, as well as oxidative stress. The present study evaluated the in vivo effect of T. evansi infection on frequency and index of DNA damage in liver, heart, spleen and total blood of rats. Twenty rats were assigned into two groups with ten rats each, being subdivided into four subgroups (A1 and A2, 5 animals/group; and B1 and B2, 5 animals/group). Rats in the subgroups A1 and A2 were used as control (uninfected) and animals in the subgroups B1 and B2 were inoculated with T. evansi (infected). NO in serum and the comet assay were used to measure DNA damage index (DI) and damage frequency (DF) in liver, heart, spleen and total blood of infected rats. Increased NO levels on days 3 and 9 post-infection (PI) was observed (P < 0.001). Also, it was verified an increase on DI and DF in the evaluated organs on days 3 and 9 PI (P < 0.001). Our data show that T. evansi infection causes genotoxicity due to the production of NO, causing not only the death of the protozoan, but also inducing DNA damage in the host.


Assuntos
Dano ao DNA , Fígado/patologia , Miocárdio/patologia , Baço/patologia , Tripanossomíase/patologia , Animais , Ensaio Cometa , Adutos de DNA/análise , Cães , Feminino , Óxido Nítrico/sangue , Óxido Nítrico/metabolismo , Parasitemia/parasitologia , Parasitemia/patologia , Ratos , Ratos Wistar , Trypanosoma/patogenicidade , Tripanossomíase/parasitologia
6.
Molecules ; 21(1): 53, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26760993

RESUMO

Dugesia tigrina is a non-parasitic platyhelminth, which has been recently utilized in pharmacological models, regarding the nervous system, as it presents a wide sensitivity to drugs. Our trials aimed to propose a model for an in vivo screening of substances with inhibitory activity of the enzyme acetylcholinesterase. Trials were performed with four drugs commercialized in Brazil: donepezil, tacrine, galantamine and rivastigmine, utilized in the control of Alzheimer's disease, to inhibit the activity of acetylcholinesterase. We tested five concentrations of the drugs, with an exposure of 24 h, and the mortality and the inhibition of acetylcholinesterase planarian seizure-like activity (pSLA) and planarian locomotor velocity (pLMV) were measured. Galantamine showed high anticholinesterasic activity when compared to the other drugs, with a reduction of 0.05 µmol·min(-1) and 63% of convulsant activity, presenting screw-like movement and hypokinesia, with pLMV of 65 crossed lines during 5 min. Our results showed for the first time the anticholinesterasic and convulsant effect, in addition to the decrease in locomotion induced by those drugs in a model of invertebrates. The experimental model proposed is simple and low cost and could be utilized in the screening of substances with anticholinesterasic action.


Assuntos
Inibidores da Colinesterase/farmacologia , Convulsivantes/farmacologia , Galantamina/farmacologia , Indanos/farmacologia , Piperidinas/farmacologia , Rivastigmina/farmacologia , Tacrina/farmacologia , Animais , Donepezila , Locomoção/efeitos dos fármacos , Modelos Biológicos , Planárias/efeitos dos fármacos , Planárias/enzimologia , Convulsões/induzido quimicamente , Taxa de Sobrevida
7.
Homeopathy ; 105(1): 109-18, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26828006

RESUMO

BACKGROUND: M1 is a homeopathic medicine with immunostimulatory properties used mainly by cancer patients to complement current therapies. Metastatic melanoma is a skin-originated form of cancer without a single therapy able to produce high rate and sustained responses, which attracts the use of complementary therapies such as M1. However, M1's anti-melanoma effects remain to be pre-clinically demonstrated. Therefore in the present work, we utilized a pulmonary metastatic melanoma model and a subcutaneous melanoma growth model to investigate the potential benefits of treatment with M1. METHODS: C57BL/6 mice were injected intravenously or subcutaneously with B16F10 mouse melanoma cells. After 24 h, mice were treated with either M1 or vehicle (water) for 14 days, euthanized and harvested for multi-parameter pulmonary and tumor analyses. RESULTS: Mice treated with M1 had significantly lower tumor burden in the lungs and subcutaneous tissue than control mice. Furthermore, tumors were impaired in proliferation and tumor related angiogenesis by the inhibition of myeloid derived suppressor cells (MDSC) positive for angiotensin II type 1 receptor (AT1R). CONCLUSION: Altogether these data suggest M1 is an efficient candidate for melanoma therapy to be considered for future clinic studies as this study is the first supporting the idea that melanoma patients may benefit with the treatment. The treatment with M1 provides advantages considering the highly-diluted properties and a cost effective alternative to costly chemotherapeutic approaches with, if any, lower toxicity.


Assuntos
Homeopatia/métodos , Materia Medica/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/prevenção & controle , Terapia Respiratória/métodos , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL
8.
Pharm Biol ; 54(12): 2968-2977, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27357525

RESUMO

CONTEXT: Glioma is a malignant brain tumor with rapid proliferation, infiltrative growth, poor prognosis and it is chemoresistent. Pomegranate seed oil (PSO) has antioxidant, anti-inflammatory and antitumor properties. This study showed the optimization of PSO nanoemulsions (NEs) as an alternative for glioma treatment. OBJECTIVE: The study aimed to evaluate PSO NEs cytotoxicity on human blood cells and antiglioma effects against C6 cells. MATERIALS AND METHODS: NEs were prepared by the spontaneous emulsification method, using PSO at 1.5 and 3.0%, and were evaluated regarding their physical stability and antioxidant activity. Toxicity evaluations in human blood cells were performed in terms of cell viability, genotoxicity, lipid peroxidation, protein carbonylation, catalase activity and hemolysis at 0.1, 0.25 and 0.5 mg/mL PSO, after a 72-h incubation period. In vitro antitumor effect was determined against glioma cells after 24 and 48 h, and astrocytes were used as a non-transformed cell model. RESULTS: Formulations presented droplet size below 250 nm, low polydispersity index, negative zeta potential and pH in the acid range. NEs and PSO had scavenging capacity around 30% and promoted a proliferative effect in mononuclear cells, increasing about 50% cell viability. No genotoxic and oxidative damage was observed in lipid peroxidation, protein carbonylation and catalase activity evaluations for NEs. Hemolysis study showed a hemolytic effect at high concentrations. Moreover, formulations reduced only tumor cell viability to 47%, approximately. DISCUSSION AND CONCLUSION: Formulations are adequate and safe for intravenous administration. Besides, in vitro antitumor activity indicates that NEs are promising for glioma treatment.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Glioma , Lythraceae , Nanopartículas , Estresse Oxidativo/efeitos dos fármacos , Óleos de Plantas/uso terapêutico , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Citotoxinas/uso terapêutico , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/fisiologia , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Emulsões/farmacologia , Emulsões/uso terapêutico , Glioma/tratamento farmacológico , Glioma/metabolismo , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Estresse Oxidativo/fisiologia , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Óleos de Plantas/isolamento & purificação , Óleos de Plantas/farmacologia , Ratos , Sementes
9.
Acta Parasitol ; 67(2): 912-920, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35380402

RESUMO

PURPOSE: Trypanosoma caninum exhibits atypical epimastigote forms under axenic conditions. This study aimed to analyze this evolutionary form under different cultivation conditions and provide more information about this evolutionary form. METHODS: We selected a T. caninum isolate with a high percentage of aflagellar epimastigote forms in axenic cultures. Two separate growth curves were generated for T. caninum cultured in Schneider axenic medium and co-cultured with the DH82 cell line, followed by analysis and quantification of evolutionary forms using bright field microscopy. In addition, ultrastructural analysis of T. caninum was performed under both cultivation conditions. RESULTS: The growth curves of T. caninum under axenic and co-cultivation conditions exhibited similar profiles. However, in the axenic culture, the number of parasites was three times higher at the peak of the exponential phase than in the co-culture. In contrast to that in the axenic culture, in which only the epimastigote forms were observed along the entire curve, during co-cultivation with the DH82 cell line, differentiation was observed for the trypomastigote and spheromastigote forms in low proportions. These results demonstrated that when cultured alone, the T. caninum isolate preserved the aflagellar epimastigote form, but in the presence of DH82 canine macrophages, they differentiated into evolutionary forms, particularly trypomastigote forms. Moreover, this study is the first to describe the presence of lipid bodies, structure described as the parasite's nutritional reserve, throughout the body of T. caninum. CONCLUSIONS: These findings describe biological and ultrastructural aspects of epimastigote aflagellar and suggest that this evolutionary form may be involved in the biological cycle of T. caninum, still unknown.


Assuntos
Trypanosoma cruzi , Animais , Cultura Axênica , Linhagem Celular , Meios de Cultura , Cães , Macrófagos/parasitologia
10.
Nat Prod Res ; 36(2): 649-653, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32662359

RESUMO

The aim of this study was to evaluate the toxicity of tucumã oil nanocapsules from the Amazon region in silver catfish, Rhamdia quelen. Fish were exposed to water treated with different concentrations of tucumã nanocapsules, white, solubilized oil and surfactant vehicles. After three days of exposure, fish were euthanized and liver, gills and brain removed for analysis of the dichlorofluorescein, nitric oxide and PicoGreen® assays. Plasma was collected for assay of hepatic transaminases. The nanocapsules had a diameter of 221 ± 1.27 nm, confirmed by atomic force microscopy. The oil nanocapsules were not toxic to this species of fish, but white nanocapsules and surfactant increased the levels of reactive oxygen species. Thus, nanocapsules are promising for the transport of tucumã oil. In view of the anti-inflammatory properties of this oil, it is possible to envisage its application in skin diseases for example, since they present essentially inflammatory conditions.HighlightsThe most abundant carotenoid in tucumã oil was all-trans-beta-carotene.Nanocapsules are good carriers for tucumã oil.Tucumã oil nanocapsules does nothas toxicity effect in catfish.


Assuntos
Peixes-Gato , Nanocápsulas , Animais , Brânquias , Fígado , Modelos Teóricos
11.
Neurol Sci ; 32(3): 375-80, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20886251

RESUMO

The objective of the study was to evaluate the caffeic acid (CA) effects against the oxidative stress (OS) observed during seizures. Wistar rats were intraperitoneally treated with either 0.9% saline (control), CA (4 mg/kg), pilocarpine (400 mg/kg, pilocarpine group), or the association of CA (4 mg/kg) plus pilocarpine (400 mg/kg). The thiobarbituric-acid-reacting substances and the hippocampal nitrite content were significantly increased (89 and 94%, respectively) in pilocarpine group when compared with control. There were marked decreases in lipid peroxidation level (43%) and nitrite content (45%) in CA group when compared with pilocarpine group. There were no marked alterations in superoxide dismutase (SOD) and catalase (CAT) activities in pilocarpine group; however, the SOD and CAT activities were significantly increased (35 and 51%, respectively) after CA pretreatment. Our findings strongly support the hypothesis that OS was indeed generated in hippocampus. CA pretreatment can reduces the OS produced by seizures.


Assuntos
Ácidos Cafeicos/farmacologia , Epilepsia/induzido quimicamente , Epilepsia/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Modelos Animais de Doenças , Epilepsia/fisiopatologia , Masculino , Degeneração Neural/tratamento farmacológico , Degeneração Neural/metabolismo , Degeneração Neural/fisiopatologia , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar
12.
Ecotoxicol Environ Saf ; 74(5): 1427-33, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21496924

RESUMO

In the present study Tradescantia pallida micronucleus (Trad-MCN) bioassay was used to assess the genotoxicity of particulate matter with a mass median aerodynamic diameter less than 10 µm (PM10) in Tangara da Serra (MT), a Brazilian Amazon region that suffers the impact of biomass burning. The levels of PM (coarse and fine size fractions) and black carbon (BC) collected were also measured. Furthermore, the alkanes and polycyclic aromatic hydrocarbons (PAHs) were identified and quantified in the samples taken during the burning period by gas chromatography with flame ionization detection (GC-FID). The PM and BC results for both fractions indicate a strong correlation (p < 0.001). The analysis of alkanes indicates an anthropic influence. Retene was the most abundant PAH found, an indicator of biomass burning, and 12 other PAHs considered to be potentially mutagenic and/or carcinogenic were identified in this sample. The Trad-MCN bioassay showed a significant increase in micronucleus frequency during the period of most intense burning, possibly related to the mutagenic PAHs that were found in such extracts. This study demonstrated that Trad-MCN was sensitive and efficient in evaluating the genotoxicity of organic compounds from biomass burning. It further emphasizes the importance of performing chemical analysis, because changes in chemical composition generally have a negative effect on many living organisms. This bioassay (ex situ), using T. pallida with chemical analysis, is thus recommended for characterizing the genotoxicity of air pollution.


Assuntos
Poluentes Atmosféricos/toxicidade , Mutagênicos/toxicidade , Material Particulado/toxicidade , Tradescantia/efeitos dos fármacos , Poluentes Atmosféricos/análise , Alcanos/análise , Alcanos/toxicidade , Atmosfera/química , Biomassa , Brasil , Dano ao DNA , Monitoramento Ambiental , Incêndios , Mutagênicos/análise , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Fuligem/análise , Fuligem/toxicidade
13.
Nat Prod Res ; 35(12): 2060-2065, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34096432

RESUMO

In this work was to develop an inedited nanocapsule with tucumã oil (Astrocaryum vulgare). The oil presents of phytosterols (squalene and ß-sitosterol), all-trans-beta-carotene, acids oleic and palmitic. Antioxidant activity showed a good performance in DPPH and ABTS assays. The nanocapsules were prepared and demonstrated in their characterization particle size (206 ± 0.69 nm). The cytogenotoxicity evaluation was performed using the MTT, dichlorofluorescein, nitric oxide and dsDNA PicoGreen® assays. Antitumor efficacy assays in MCF-7 cells demonstrated that free oil and tucumã nanocapsules had IC50 of 130 and 50 µg/mL, respectively. Thus, previous studies of toxicity are relevant, as they generate future subsidies, aiming at the potential application of nanostructures and in addition, the promising effect of NCs of tucumã oil on the antiproliferative effect in breast adenocarcinoma cells was evidenced.


Assuntos
Antioxidantes/farmacologia , Arecaceae/química , Nanocápsulas/química , Compostos Fitoquímicos/farmacologia , Óleos de Plantas/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/análise , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Tamanho da Partícula , Compostos Fitoquímicos/análise , Fitosteróis/análise , Óleos de Plantas/química
14.
Pathogens ; 9(9)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906826

RESUMO

This study describes the morphological, biochemical, and molecular differences among Trypanosoma dionisii isolates from hemocultures of hematophagous (Desmodus rotundus; n = 2) and insectivorous (Lonchorhina aurita; n = 1) bats from the Atlantic Rainforest of Rio de Janeiro, Brazil. Fusiform epimastigotes from the hematophagous isolates were elongated, whereas those of the insectivorous isolate were stumpy, reflected in statistically evident differences in the cell body and flagellum lengths. In the hemocultures, a higher percentage of trypomastigote forms (60%) was observed in the hematophagous bat isolates than that in the isolate from the insectivorous bat (4%), which demonstrated globular morphology. Three molecular DNA regions were analyzed: V7V8 (18S rDNA), glycosomal glyceraldehyde 3-phosphate dehydrogenase gene, and mitochondrial cytochrome b gene. The samples were also subjected to multilocus enzyme electrophoresis and random amplified polymorphic DNA analysis. All isolates were identified as T. dionisii by phylogenetic analysis. These sequences were clustered into two separate subgroups with high bootstrap values according to the feeding habits of the bats from which the parasites were isolated. However, other T. dionisii samples from bats with different feeding habits were found in the same branch. These results support the separation of the three isolates into two subgroups, demonstrating that different subpopulations of T. dionisii circulate among bats.

15.
Colloids Surf B Biointerfaces ; 173: 798-805, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30551295

RESUMO

We evaluated the influence of nanoencapsulation of the flavonoid Dihydromyricetin (DMY) in reducing the genotoxicity and cytotoxicity induced by cationic nanocapsules. Assays were conducted in order to evaluate the potential of protein corona formation, cytotoxicity, genotoxicity and the antioxidant capacity. Nanocapsules containing DMY (NC-DMY) and free DMY (DMY-F) did not demonstrate cytotoxicity and genotoxicity. However, Eudragit RS100® nanocapsules (NC-E) increased cytotoxicity and DNA damage formation. NC-DMY and NC-E presented high interaction with the DNA in vitro, suggesting DNA sequestration. These results indicate that nanoencapsulated DMY does not induce cytotoxicity or genotoxicity, and demonstrates high antioxidant capacity. This antioxidant capacity is probably associated with DMY, and occurs due to its ability to avoid the formation of free radicals, thus preventing the toxicity caused by the nanostructure with the cationic polymer Eudragit RS100®. Therefore, NC-DMY can be considered an important formulation with significant antioxidant potential to be exploited by nanomedicine.


Assuntos
Flavonóis/química , Nanocápsulas/química , Resinas Acrílicas/química , Antioxidantes/química , Cátions , Linhagem Celular Tumoral , Sobrevivência Celular , Ensaio Cometa , Dano ao DNA , Flavonoides/química , Humanos , Leucócitos Mononucleares/citologia , Células MCF-7 , Nanocápsulas/toxicidade , Nanotecnologia , Tamanho da Partícula , Polímeros/química , Proteínas/química
16.
Life Sci ; 82(19-20): 1018-22, 2008 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-18433794

RESUMO

In this study, the contribution of liver glycogenolysis and gluconeogenesis in the defense against short-term insulin induced hypoglycemia (IIH) was investigated. For this purpose, we used an experimental model in which IIH was obtained by administering an IP injection of a pharmacological dose (1 U/kg) of regular insulin to rats that had been deprived of food for a period of six hours. This experimental model is suitable to study the simultaneous participation of glycogen breakdown and gluconeogenesis in the defense against IIH. The livers of IIH rats showed insignificant changes in the glycogen concentration, total phosphorylase, active phosphorylase, and percent of active phosphorylase. Our results also indicated that the livers of IIH rats that received the concentration of L-alanine, L-glutamine, L-lactate, or glycerol found in the blood during IIH (basal values) showed negligible glucose production. Nonetheless, glucose, urea, and pyruvate production increased (P<0.05) if the livers were perfused with a saturating concentration of gluconeogenic precursors. In agreement with these results, IIH rats that received intragastric L-alanine, L-glutamine, or L-lactate showed increased (P<0.05) glycemia 30 min after the administration of these substances. However, when using glycerol, higher glycemia (P<0.05) was observed at 2 and 5 min, but not 30 min after the administration of this hepatic gluconeogenic precursor. Thus, we can conclude that the oral availability of gluconeogenic precursors could allow for their use as important antidote in the defense against IIH.


Assuntos
Gluconeogênese , Glicogenólise , Hipoglicemia/metabolismo , Insulina/efeitos adversos , Fígado/efeitos dos fármacos , Aminoácidos/administração & dosagem , Aminoácidos/farmacologia , Animais , Privação de Alimentos , Gluconeogênese/efeitos dos fármacos , Glicogenólise/efeitos dos fármacos , Hipoglicemia/induzido quimicamente , Fígado/metabolismo , Masculino , Ratos , Ratos Wistar , Fatores de Tempo
17.
Naunyn Schmiedebergs Arch Pharmacol ; 391(7): 753-759, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29691607

RESUMO

Trypanosoma evansi is a zoonotic parasite associated with high animal mortality that has gained importance due to its capacity to infect humans. Recently, some evidences have demonstrated that T. evansi infection causes severe genotoxic and cytotoxic damage in brain cells, contributing to the pathogenesis and clinical signs of the disease. In this sense, the aim of this study was to evaluate whether nerolidol-loaded in nanospheres, a natural compound with trypanocidal and neuroprotective effects, is able to protect the brain tissue from the cytotoxic and genotoxic effects found during T. evansi infections. Trypanosoma evansi induced brain genotoxic effects through increased damage index (DI) and frequency of damage (FD) when compared to the control group. Moreover, T. evansi induced cytotoxic effects through the reduction of brain cell viability compared to the control group. The metabolites of nitric oxide (NO x ) increased in infected animals compared to the control group. The treatment with nerolidol-loaded in nanospheres prevented the increase on brain DI, FD, and NO x levels, as well as the reduction on cell viability. Based on these evidences, these results confirm that T. evansi induces genotoxic and cytotoxic damage mediated by the upregulation of NO x levels. The most important finding is that nerolidol-loaded in nanospheres was able to prevent DNA damage and cell mortality through the modulation of brain NO x levels. In summary, this treatment can be considered an interesting approach to prevent T. evansi brain damage due its anti-inflammatory property.


Assuntos
Encéfalo/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Sesquiterpenos/uso terapêutico , Tripanossomíase/tratamento farmacológico , Animais , Encéfalo/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Feminino , Camundongos , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico/metabolismo , Sesquiterpenos/farmacologia , Tripanossomíase/metabolismo
18.
Biomed Res Int ; 2017: 2723418, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28691021

RESUMO

Essential oil of Eucalyptus globulus presents several pharmacological properties. However, their therapeutic efficacy may be affected by limitations due to several conditions, rendering it difficult to obtain stable and effective pharmaceutical formulations. The use of nanotechnology is an alternative to improve their characteristics aiming to ensure their stability and effectiveness. Furthermore, studies about the possible toxic effects of nanostructures are necessary to evaluate safety when the formulation comes into contact with human cells. Hence, in this paper, we evaluate for the first time the stability and in vitro cytogenotoxicity of nanoemulsions containing Eucalyptus globulus in peripheral blood mononuclear cells. As a result, the stability study found that the best condition for storage up to 90 days was refrigeration (4°C); it was the condition that best preserved the nanometric features. The content of the major compounds of oil was maintained after nanoencapsulation and preserved over time. In tests to evaluate the safety of this formulation, we can conclude that, at a low concentration (approximately 0.1%), Eucalyptus globulus nanoemulsion did not cause toxicity in peripheral blood mononuclear cells and also showed a protective effect in cells against possible damage when compared to oil in free form.


Assuntos
Emulsões/química , Eucalyptus/química , Nanoestruturas/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Hemólise/efeitos dos fármacos , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Nanoestruturas/ultraestrutura , Carbonilação Proteica/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
19.
Chem Biol Interact ; 270: 51-58, 2017 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-28419827

RESUMO

The aim of the study was to investigate the effect of the oral administration of tucumã oil (Astrocaryum vulgare) on glucose and insulin levels, oxidative status, and pancreatic genotoxic parameters of alloxan-induced diabetic mice. The animals were divided into four groups (n = 6 each): control/water; control/tucumã oil; diabetic/water; diabetic/tucumã oil treated for 14 days with 5.0 mL kg-1 via oral gavage. Gas chromatograph characterization demonstrated that oleic/elaidic fatty acid is the most abundant component present in this oil, followed by palmitic and stearic fatty acids. Our results demonstrated an increase (p < 0.05) in water and food intake, blood glucose, thiobarbituric acid reactive species (TBARS) levels, damage index, and frequency of damage; conversely body weight, insulin levels, catalase (CAT) and superoxide dismutase (SOD) activities, and cell viability were decreased in the diabetic/water group compared to the control/water group. The treatment with tucumã oil prevented these alterations in the diabetic/tucumã oil group compared to the diabetic/water group, and restored these parameters near to the control/water group. In summary, our findings demonstrated that treatment with tucumã oil causes a hypoglycemic effect improving insulin levels and antioxidant/oxidant status, and has a protector effect against pancreatic damage induced by oxidative stress in alloxan-induced diabetic mice.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Ácidos Graxos/sangue , Hiperglicemia/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Aloxano/toxicidade , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Peso Corporal/efeitos dos fármacos , Cromatografia Gasosa , Diabetes Mellitus Experimental/induzido quimicamente , Ativação Enzimática/efeitos dos fármacos , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Camundongos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Superóxido Dismutase/metabolismo
20.
Environ Toxicol Pharmacol ; 46: 1-8, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27400424

RESUMO

The neurotoxic effects and activity of Na(+), K(+)-ATPase and NTPDase in Wistar rats after treatment with α-terpinene (daily oral administration of 0.5, 0.75 and 1.0mLkg(-1) for 10days) were examined. Results of the inhibitory avoidance task showed a memory deficit (p<0.05) in rats treated with all doses of α-terpinene. The evaluation of DNA damage in brain tissue revealed an increase (p<0.05) on frequency of damage and damage index in all concentrations. According to the cytotoxicity assay, doses of 0.5, 0.75 and 1.0mLkg(-1) increase the lactate dehydrogenase levels, and doses of 1.0mLkg(-1) also decrease (p<0.05) cell viability in brain cells. A decrease (p<0.05) on Na(+), K(+)-ATPase activity in brain tissue and on NTPDase activity in serum were observed in all concentrations of α-terpinene. These results suggest that the α-terpinene was cytotoxic and genotoxic to the brain cells by inducing loss of cell viability and DNA damage, as well as causing alterations in Na(+), K(+)-ATPase and NTPDase activity, what may contribute to the memory deficit of treated animals. Thus, α-terpinene cannot be consumed by the population at the doses studied.


Assuntos
Encéfalo/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Monoterpenos/toxicidade , Pirofosfatases/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Administração Oral , Animais , Encéfalo/metabolismo , Monoterpenos Cicloexânicos , Dano ao DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Monoterpenos/administração & dosagem , Testes de Mutagenicidade , Pirofosfatases/sangue , Ratos Wistar
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