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1.
Artigo em Inglês | MEDLINE | ID: mdl-35047045

RESUMO

The incidence of liver diseases, such as nonalcoholic fatty liver disease and drug-induced liver injury, continues to rise and is one of the leading causes of acute hepatitis. Current trends suggest that these types of conditions will increase in the coming years. There are few drugs available for the prevention or treatment of hepatic diseases, and there is a growing need for the development of safe hepatoprotective agents. The medicinal plant, Turnera diffusa, has many ethnopharmacological uses, one of which is the production of a flavonoid named hepatodamianol, which is the principal component responsible for this plant's hepatoprotective properties. In the present study, we describe the development and standardization of an active extract obtained from T. diffusa. We conducted nuclear magnetic resonance spectroscopy to identify hepatodamianol unambiguously in each sample. Using this extract, hepatoprotection could be demonstrated in vivo for the first time. The hepatoprotective effect did not display a significant difference in vivo when compared with silymarin used as a positive control at the same doses. Implementation of quality criteria used for standardization, such as flavonoid and hepatodamianol content, hepatoprotective activity, and absence of residual solvents, will allow future preclinical trials with this herbal drug.

2.
Beilstein J Nanotechnol ; 13: 1505-1519, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36605610

RESUMO

Green synthesis may be a useful approach to achieve selective cytotoxicity of silver nanoparticles on cancer cells and healthy cells. In this study, the concomitant biosynthesis of silver (Ag)/silver chloride (AgCl) nanoparticles from pineapple peel extracts and their behavior on the breast cancer cell line MCF-7 is shown. Bioreactions were monitored at different temperatures. Fourier-transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis), thermogravimetric analysis (TGA), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM) techniques were used to characterize nanoparticle development. The breast cancer cell line MCF-7 was used as a test model to study the cytotoxic behavior of Ag/AgCl nanoparticles and, as a counterpart, the nanoparticles were also tested on mononuclear cells. Ag/AgCl nanoparticles with spherical and triangular morphology were obtained. The size of the nanoparticles (10-70 nm) and the size distribution depended on the reaction temperature. A dose close to 20 µg/mL of Ag/AgCl nanoparticles considerably decreased the cell viability of the MCF-7 line. The best cytotoxicity effects on cancer cells were obtained with nanoparticles at 60 and 80 °C where cell viability was reduced up to 80% at a concentration of 50 µg/mL. A significant preference was observed in the cytotoxic effect of Ag/AgCl nanoparticles against cancer cells in comparison to monocytes.

3.
J Anal Methods Chem ; 2019: 2837406, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30881726

RESUMO

The essential oils (EO) of R. officinalis and L. dentata have been widely used due to their antioxidant activity. However, due to their high volatility, the loading of EO into polymeric nanocapsules (NC) represents an efficient way of retaining their effect in future topical administration. In this way, the quantitative determination of EO incorporated into NC is necessary for simultaneous monitoring of the main components of the EO during the nanoencapsulation process as well as for precise and exact dosing of the components used during the performance of in vitro and in vivo biological tests. In this study, EO were isolated by hydrodistillation in a Clevenger-type apparatus and characterized by GC-MS and GC-FID analyses. The major constituents of EO-R. officinalis were camphor (39.46%) and 1,8-cineole (14.63%), and for EO-L. dentata were 1,8-cineole (68.59%) and ß-pinene (11.53%). A new analytical method based on GC-FID for quantification of free and encapsulated EO was developed and validated according to ICH. Linearity, limit of detection and quantification, and intra- and interday precision parameters were determined. The methods were linear and precise for the quantification of the main components of EO. The EO were encapsulated by nanoprecipitation and were analyzed by the GC-FID method validated for their direct quantification. The NC size was 200 nm with homogeneous size distribution. The quantification of the incorporated EO within a NC is an important step in NC characterization. In this way, an encapsulation efficiency of at least 59.03% and 41.15% of total EO-R. officinalis and EO-L. dentata, respectively, was obtained. Simple, repeatable, and reproducible methods were developed as an analytical tool for the simultaneous quantification of the main components of EO loaded in polymeric nanocapsules as well as their monitoring in biological assays.

4.
Curr Med Chem ; 25(31): 3719-3747, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29521201

RESUMO

Chronic kidney disease (CKD) is a progressive condition characterized by a permanent and irreversible loss of renal function. In accordance to international guidelines, CKD clinical diagnosis methods are based on creatinine and albumin levels and glomerular filtration rate. Unfortunately, these parameters are scarcely affected in early stages, and its inherent intrinsic variability only allows for the identification of intermediate and advanced stages, when life expectancy has become shorter and treatment poses a significant financial investment. In this context, several targeted strategies have been designed for searching novel markers. Among them, "omics" techniques have emerged, mainly based on proteomics and metabolomics research. Urine and serum samples have been selected as starting material to conduct the identification of new CKD biomarkers, capable of differentiating between stages and predicting progression outcomes. In many cases, the principal objective is to develop a fast and reliable clinical method for non-invasive analysis in the early progression stages of the disease. On the other hand, significant efforts have been directed to identify molecules related to the CKD end stage in order to adequate therapies, reduce impairments, and have a positive impact on survival rate. In this article, the state of the art of novel proposed biomarkers for CKD identification is reviewed, with the aim of underlining its molecular diversity, emphasizing chemical structure differences and correlating its biological relevance. Efforts directed in this line could provide evidence of metabolic pathways imbalance, and lead to the development of new integral strategies for CKD evaluation and management.


Assuntos
Biomarcadores/metabolismo , Insuficiência Renal Crônica/diagnóstico , Aminoácidos/sangue , Aminoácidos/metabolismo , Aminoácidos/urina , Animais , Biomarcadores/sangue , Biomarcadores/urina , Progressão da Doença , Feminino , Humanos , Masculino , Prognóstico , Proteínas/análise , Proteínas/metabolismo , Insuficiência Renal Crônica/fisiopatologia
5.
Nat Prod Commun ; 7(11): 1441-4, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23285803

RESUMO

Chemical studies on Hamelia patens (Rubiaceae) micropropagated plantlets allowed production of a new monoterpenoid oxindole alkaloid, named (-)-hameline (7), together with eight known alkaloids, tetrahydroalstonine (1), aricine (2), pteropodine (3), isopteropodine (4), uncarine F (5), speciophylline (6), palmirine (8), and rumberine (9). The structure of the new alkaloid was assigned on the basis of 1D and 2D NMR spectroscopy, mass spectrometry, and molecular modeling.


Assuntos
Alcaloides/isolamento & purificação , Hamelia/química , Monoterpenos/isolamento & purificação , Alcaloides/química , Técnicas de Cultura , Estrutura Molecular , Monoterpenos/química
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