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1.
Molecules ; 29(18)2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39339351

RESUMO

BACKGROUND: Athenaea fasciculata, a Brazilian native species from the Solanaceae family, is recognized as a promising source of bioactive withanolides, particularly Aurelianolide A and B, which exhibit significant antitumoral activities. Despite its potential, research on the chemical constituents of this species remains limited. This study aimed to dereplicate extracts and partitions of A. fasciculata to streamline the discovery of bioactive withanolides. METHODS: Using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), various extracts-including n-hexane, methanol, and ethanol-were analyzed, and their mass spectrometry data were processed through the GNPS platform for the generation of molecular networking. The results indicated that crude extracts displayed comparable cytotoxicity against Jurkat cells, by treatment at 150 µg/mL, while alcoholic extracts achieved approximately 80% inhibition of K562 cells and K562-Lucena 1 at the same concentration. Notably, the dichloromethane partition exhibited the highest cytotoxicity across leukemia cell lines, particularly against Jurkat cells (IC50 = 14.34 µg/mL). A total of 22 compounds were annotated by manual inspection and different libraries, with six of them demonstrating significant cytotoxic effects. CONCLUSIONS: This research underscores the therapeutic potential of A. fasciculata and highlights the effectiveness of integrating advanced analytical methods in drug discovery, paving the way for further exploration of its bioactive compounds.


Assuntos
Antineoplásicos Fitogênicos , Extratos Vegetais , Espectrometria de Massas em Tandem , Vitanolídeos , Humanos , Vitanolídeos/farmacologia , Vitanolídeos/química , Vitanolídeos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células Jurkat , Solanaceae/química , Espectrometria de Massas por Ionização por Electrospray , Linhagem Celular Tumoral , Células K562
2.
Braz. arch. biol. technol ; Braz. arch. biol. technol;48(spe2): 13-27, Oct. 2005. ilus, tab
Artigo em Inglês | LILACS | ID: lil-448884

RESUMO

Clinical images are worthwhile in Health Sciences and their analysis and correct interpretation aid the professionals,such as physicians, physiotherapists and occupational therapists, to make decisions and take subsequent therapeutic and/or rehabilitation measures. Other factors, besides the state of the disease, may interfere and affect the bioavailability of the radiopharmaceuticals (radiobiocomplexes) and the quality of the SPECT and PET images. Furthermore, the labeling of some of these radiobiocomplexes, such as plasma proteins, white blood cells and red blood cells, with 99mT, can also be modified. These factors include drugs (synthetic and natural) and dietary conditions, as well as some medical procedures (invasive or non-invasive), such as radiation therapy, surgical procedures, prostheses, cardioversion, intubation, chemoperfusion, external massage, immunotherapy, blood transfusion and hemodialysis. In conclusion, the knowledge about these factors capable of interfering with the bioavailability of the radiobiocomplexes is worthwhile for secure diagnosis. Moreover, the development of biological models to study these phenomena is highly relevant and desirable.


Imagens clínicas são valiosas em Ciências da Saúde e a análise e a interpretação correta das mesmas auxiliam os profissionais, como médico, fisioterapeuta, terapeuta ocupacional, na tomada de decisões e subseqüentes ações terapêuticas e/ou de reabilitação. Além das doenças outros fatores podem interferir e afetar a biodisponibilidade dos radiofármacos (radiobiocomplexos) e a qualidade das imagens (SPECT e PET). Além disso, a marcação de alguns desses radiobiocomplexos com Tc-99m, como proteínas plasmáticas, leucócitos e hemácias, também pode ser modificada. Entre esses fatores, estão drogas (sintéticas e naturais) e condições alimentares, assim como alguns procedimentos médicos (invasivos e não invasivos), como a radioterapia, processos cirúrgicos, próteses, cardioversão, intubação, quimioperfusão, massagem externa, imunoterapia, transfusão sanguínea e hemodiálise. Em conclusão, o conhecimento sobre esses efeitos capazes de interferir na biodisponibilidade de radiobiocomplexos é altamente relevante para diagnósticos precisos. Além disso, o desenvolvimento de modelos biológicos para estudar esses fenômenos é de elevada importância e desejável.

3.
Rev. bras. farmacogn ; 15(2): 126-132, abr.-jun. 2005. ilus, tab
Artigo em Inglês | LILACS | ID: lil-570898

RESUMO

Plants have been used for the human beings as food, as additives and/or as medicines. There are controversies about the biological effects of several natural products and, it is worthwhile to try to develop experimental assays to evaluate properties of extracts of plants. Pfaffia sp. is utilized in popular medicine and various properties have been attributed to its extract. Red blood cells (RBC) and plasma proteins are labeled with technetium-99m (Tc-99m) and this labeling procedure depends on a reducing agent and stannous ion is usually used. There are reports that drugs can alter the labeling of blood elements with Tc-99m. We have evaluated the influence of a Pfaffia sp. extract on the labeling of blood constituents with Tc-99m and on the morphology of RBC. Blood was incubated with an aqueous extract of Pfaffia sp., stannous chloride and Tc-99m. Samples were centrifuged and plasma and blood cells were separated and also precipitated with trichloroacetic acid. Soluble and insoluble fractions were separated. The results did not show alteration in the uptake of radioactivity and no modifications on the shape of the RBC in presence of Pfaffia sp. Once this labeling process depends on a reducing agent, probably, this extract has compounds with anti-oxidant properties as already described elsewhere, that could protect the stannous ions against the oxidation process. This fact would aid the labeling process of blood elements with Tc-99m.

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