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1.
Braz J Microbiol ; 54(3): 1513-1521, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37540461

RESUMO

The aim of this study was to evaluate the efficacy and non-toxicity of ciclopirox olamine-loaded liposomes against Cryptococcus neoformans clinical isolates. Initially, 24-1 fractional experimental design was carried out to obtain an optimized formulation of liposomes containing CPO (CPO-LipoC), which were then used to prepare stealth liposomes (CPO-LipoS). Liposomal formulations were characterized by their mean size diameter, polydispersity index (PDI), and drug encapsulation efficiency (EE%). Immunosuppressed mice were exposed to CPO-LipoS at 0.5 mg/kg/day for 14 days to verify possible histopathological alterations in the liver and kidneys. Immunosuppressed mice infected with C. neoformans were treated with CPO-LipoS at 0.5 mg/kg/day for 14 days to quantify the fungal burden in spleen, liver, lungs, and brain. CPO-LipoS presented a mean size diameter, PDI, and EE% of 101.4 ± 0.7 nm, 0.307, and 96.4 ± 0.9%, respectively. CPO-LipoS was non-toxic for the liver and kidneys of immunosuppressed mice. At the survival curve, all infected animals submitted to treatment with CPO-LipoS survived until the end of the experiment. Treatment with CPO-LipoS reduced C. neoformans cells in the spleen (59.3 ± 3.4%), liver (75.0 ± 3.6%), lungs (75.7 ± 6.7%), and brain (54.2 ± 3.2%). CPO-LipoS exhibit antifungal activity against C. neoformans, and the encapsulation of CPO into stealth liposomes allows its use as a systemic drug for treating cryptococcosis.


Assuntos
Criptococose , Cryptococcus neoformans , Animais , Camundongos , Ciclopirox/uso terapêutico , Lipossomos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Criptococose/tratamento farmacológico , Criptococose/microbiologia
2.
Prep Biochem Biotechnol ; 51(4): 375-385, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32940546

RESUMO

Calotropis procera produces a milky sap containing proteolytic enzymes. At low concentrations, they induce milk-clotting (60 µg/ml) and to dehair hides (0.05 and 0.1%). A protocol for obtaining the enzymes is reported. The latex was mixed with distilled water and the mixture was cleaned through centrifugation. It was dialyzed with distilled water and centrifuged again to recover the soluble fraction [EP]. The dialyze is a key feature of the process. EP was characterized in terms of protein profile, chemical stability, among other criteria. Wild plants belonging to ten geographic regions and grown in different ecological conditions were used as latex source. Collections were carried out, spaced at three-month, according to the seasons at the site of the study. Proteolytic activity was measured as an internal marker and for determining stability of the samples. EP was also analyzed for metal content and microbiology. EP showed similar magnitude of proteolysis, chromatographic and electrophoretic profiles of proteins. Samples stored at 25 °C exhibited reduced solubility (11%) and proteolytic capacity (11%) after six months. Enzyme autolysis was negligible. Microbiological and metal analyses revealed standard quality of all the samples tested. EP induced milk clotting and hide dehairing after storage for up to six months.


Assuntos
Ácido Aspártico Endopeptidases/metabolismo , Calotropis/enzimologia , Técnicas de Química Analítica/normas , Ecossistema , Látex/química , Proteínas de Plantas/metabolismo , Estações do Ano , Pelo Animal/efeitos dos fármacos , Animais , Ácido Aspártico Endopeptidases/análise , Ácido Aspártico Endopeptidases/química , Ácido Aspártico Endopeptidases/farmacologia , Bovinos , Cabras , Remoção de Cabelo/métodos , Látex/isolamento & purificação , Proteínas de Plantas/análise , Proteínas de Plantas/química , Proteínas de Plantas/farmacologia , Proteólise , Padrões de Referência , Solubilidade
3.
Appl Biochem Biotechnol ; 182(3): 1229-1239, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28078650

RESUMO

Calotropis procera latex fractions possessing anti-inflammatory property were characterized for their biochemical properties, compared for their efficacy in ameliorating fever in rats and their mechanism of action was elucidated. Aqueous fraction and methanol extract (AqDL and MeDL) were derived from the dried latex (DL) and proteins were separated from the fresh latex (LP). Polyacrylamide gel electrophoresis carried out under denaturing conditions showed the presence of proteins with some similarity in LP and AqDL and both of these fractions exhibited proteinase activity by gelatin zymography. A further analysis revealed that only the LP fraction possesses cysteine proteinase activity. Oral administration of both AqDL and MeDL produced a dose-dependent reduction in body temperature in rats where fever was induced by yeast and their effect was comparable to that of standard drug paracetamol while intravenous administration of LP was not so effective. Both AqDL and MeDL produced a significant reduction in the levels of TNF-α, PGE2, and immunoreactivity of COX-2 in the hypothalamus as compared to yeast control group. This study shows that both AqDL and MeDL, the orally effective anti-inflammatory fractions of latex, have therapeutic potential in treating various febrile conditions.


Assuntos
Anti-Inflamatórios/farmacologia , Calotropis/química , Febre/tratamento farmacológico , Látex/química , Extratos Vegetais/farmacologia , Administração Oral , Animais , Anti-Inflamatórios/química , Ciclo-Oxigenase 2/metabolismo , Dinoprostona/metabolismo , Relação Dose-Resposta a Droga , Febre/metabolismo , Febre/patologia , Hipotálamo/metabolismo , Hipotálamo/patologia , Extratos Vegetais/química , Proteínas de Plantas/química , Proteínas de Plantas/farmacologia , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
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