Navegando por Palavras-chave "Atividade citotóxica"

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    Análise química e biológica dos constituintes fixos e voláteis de Casearia sylvestris sw. (Salicaceae)
    (Universidade Federal de São Paulo, 2013-10-05) Bou, Diego Dinis [UNIFESP]; Sartorelli, Patricia [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The present work aimed at the isolation of the chemical constituents of C. sylvestris (Salicaceae), as well as evaluating the cytotoxic activity against tumor cell lines and assays for detection of anti-Leishmania activity and anti-Trypanosoma, beyond the description of constituents the essential oil, the major component structural modification and evaluation of the cytotoxic activity of oil and its derivatives. The hexane phase obtained from MeOH extract of leaves of C. sylvestris was subjected to fractionation steps on Sephadex LH-20, silica gel, CCDP and HPLC gel. After several purification steps were identified by spectroscopic techniques, casearins A, B, G, J, and a novel diterpene clerodane-dinor. The cytotoxic effect of these compounds was evaluated against tumor cell lines (B16F10, A2058, HL-60, HCT, MCF7, HeLa cells) using the MTT method, and the activity of anti-Leishmania promastigotes front L. braziliensis, L. amazonensis, L. infantum and anti-Trypanosoma activity against T. cruzi. The tests showed that the antiparasitic casearins showed EC50 values very significant for promastigotes of Leishmania, but also showed high toxicity. Stood out however, the activities against trypomastigotes of T. cruzi with EC50 = 0.53 g / mL for J. casearin was also observed that casearins cause changes in the permeability of the plasma membrane of T. cruzi through the trials of spectrofluorometry. Cytotoxicity analysis showed that the isolated casearins also showed promising results EC50 for tumor cell lines tested, suggesting that the cytotoxic activity is directly related to casearins. The oil 23 comprises substances proved, and the -zingiberene the major component (48%). The cytotoxic Oil analysis showed that addition of the crude oil, zingiberene and derivatives also exhibited cytotoxic activity. The results suggest a potential for the prototypes of antitumor drugs and antiparasitic, from casearins and zingiberene.
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    Atividade citotóxica de secretoma de Aspergillus fumigatus em células de carcinoma de pulmão
    (Universidade Federal de São Paulo (UNIFESP), 2017-12-21) Sousa, Ana Cristina Peres de [UNIFESP]; Colombo, Arnaldo Lopes [UNIFESP]; Xafranski, Hemílio [UNIFESP]; http://lattes.cnpq.br/6365132166365924; http://lattes.cnpq.br/4512261018429681; http://lattes.cnpq.br/2185359879862979; Universidade Federal de São Paulo (UNIFESP)
    Introduction Aspergillus fumigatus is a fungi with high adaptive capacity and virulence factors that favors its establishment and colonization in the human host. Species of Aspergillus genus are recognized for its high capacity for production of secondary metabolites, extensively documented in the literature. Among these metabolites, there are some isolated molecules used as drugs, for the cholesterol control (lovastatin) and even in the combat of other fungi (echinocandins). Several molecules produced by A. fumigatus have already been tested on human cells/ in vitro cells searching for bioactive molecules. Gliotoxin is one of the most studied A. fumigatus molecule, that inhibits the host immune response, negatively modulating angiogenesis and inducing many cell lines to apoptosis. In view of the great diversity of molecules produced by A. fumigatus, the interest to explore its biological potential focusing on cytotoxic activity in lung carcinoma cells, the target organ of infection by this agent in the human host is justified. Objective To obtain the secretome from clinical isolates of A. fumigatus and investigate the potential cytotoxic activity of its fractions on A549 cells. Methodology Six clinical isolates of A. fumigatus from patients with pulmonary aspergillosis were identified at species level using a polyphasic approach, including ITS region, Calmodulin and β-tubulin genes sequencing. After standardization of the optimal conditions to obtain secretomes samples with reproducible composition (same profile when evaluated by LC-MS), we started the screening for biological activity of these molecules in A549 cells through cytotoxicity assays in which measurement of metabolic activity was done by the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide salt (MTT) assay. Once that the most active secretome was identified, it was submitted to sequential fractionations through preparative Liquid Chromatography (LC), with the aim of purifying the fraction that was responsible for the cytotoxic effect found. Finally, annexin V cell death assays were performed to analyse the cell death pattern induced by the active subfraction. Result The standardization of A549 cell culture and secretome extraction in MMBA culture medium of reproducible composition was successfully achieved. Regarding the biological activity of secretome samples from 6 A. fumigatus isolates, the isolate 934 was presented the highest cytotoxic effect in MTT assays. From this finding, 2 sequential secretome fractionations were performed and it was possible to isolate a subfraction identified as Z5, which presented consistent cytotoxic activity, reducing 90% of cell viability when compared to control (p <0.02). The annexin V assay has led to the conclusion that this subfraction mainly induces apoptosis in A549 cells. New assays are needed to characterize the A. fumigatus secretome subfraction that presented cytotoxic activity as well as to confirm its potential antitumor activity.
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    Atividade citotóxica in vitro dos metabólicos das folhas de Piper cernuum vell (Piperaceae) e derivados monoterpênicos naturais e semissintéticos
    (Universidade Federal de São Paulo, 2013-08-23) Capello, Tabata Molero [UNIFESP]; Lago, João Henrique Ghilardi [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    No presente trabalho foi realizado o estudo químico biomonitorado pela atividade citotóxica (células tumorais B16F10-Nex2) do extrato metanólico das folhas de Piper cernuum vell. (Piperaceae). Para tanto, o extrato bruto foi submetido à cromatografia em coluna (SiO2) com diferentes fases móveis (hexano, acetato de etila e metanol). Após a separação em onze grupos (A – K), estes foram analisados frente ao potencial citotóxico, dos quais apenas três grupos (D, F e G) apresentaram atividade e foram novamente purificados através de cromatografia de camada delgada preparativa. Tal procedimento permitiu o isolamento dos seguintes compostos: ácido 3,4-dimetoxidiidrocinâmico (I), piplaróxido (II) e 4-hidroxi-3,5-dimetoxidiidrocinamato de metila (III), sendo que as estruturas foram definidas através de análise dos respectivos espectros de RMN de 1H e de 13C além de EM. Todos os compostos isolados foram analisados quanto atividade citotóxica frente a células tumorais B16F10-Nex2 (melanoma murino), A2058 (melanoma humano), HeLa (carcinoma cervical), HL-60 (leucemia), U-87 (glioblastoma humano) e HCT (carcinoma ileocecal-cólon), porém apenas o composto (II) mostrou uma concentração inibitória (CI50) de 58 µg/mL para linhagem B16F10-Nex2 (melanoma murino), enquanto que todos os outros compostos isolados não mostraram potencial citotóxico para nenhuma linhagem (CI50 ≥ 100 g/mL). Adicionalmente, o óleo volátil das folhas de P. cernuum foi extraído por arraste a vapor utilizando aparelho de Clevenger e analisado por CG-EM, o que possibilitou a identificação de dezenove compostos, dentre os quais β-elemeno, biciclogermacreno e (E)--cariofileno foram os compostos majoritários. Do mesmo modo que os compostos isolados do extrato bruto, o óleo volátil também foi analisado quanto à atividade citotóxica in vitro frente às mesmas linhagens tumorais citadas acima, apresentando potencial em todas as linhagens (CI50 variando de 15,5 ± 3,5 a 30 ± 2 µg/mL). Além disso, nesse trabalho foi avaliada a atividade citotóxica de onze monoterpenos naturais (α-pineno, β-pineno, canfeno, limoneno, carvacrol, timol, p-cimeno, mirceno, linalol, α-terpineol e mentol) frente às linhagens tumorais B16F10-Nex2 (melanoma murino), A2058 (melanoma humano), HeLa (carcinoma cervical) e HL-60 (leucemia), sendo os derivados α-pineno, β-pineno, canfeno, limoneno, carvacrol e timol os mais ativos. Foram preparados seus derivados semissintéticos hidrogenados (canfano e p-mentano) e acetilados (acetatos de carvacrol e de timol), cujas estruturas foram identificadas por análises dos espectros de RMN 13C e EM. Tais compostos semissintéticos foram também analisados quanto à atividade citotóxica frente às mesmas linhagens tumorais dos monoterpenos naturais, mostrando-se ativo apenas para o composto semissintético p-mentano (CI50 28 ± 6 µg/mL) o qual mostrou atividade similar ao monoterpeno natural limoneno (CI50 33 ± 3 µg/mL).
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    Busca de compostos com ação citotóxica em Porcelia macrocarpa R. E. Fries (Annonaceae)
    (Universidade Federal de São Paulo, 2015-11-09) Ferreira, Loraine Elizabeth Martins [UNIFESP]; Lago, João Henrique Ghilardi [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    This work describes the evaluation of the in vitro cytotoxic activity and bioactivity guided fractionation of the extracts in hexane and CH2Cl2 of Porcelia macrocarpa seeds. In order to do this, extracts in hexane and CH2Cl2 were prepared and submitted to evaluation of the cytotoxic potential against B16F10Nex2 cell line (murine melanoma). As the CH2Cl2 extract displayed activity (cell viability 45±3% to 50 ?g/mL and 34±2% to 25 ?g/mL) it was fractionated on silica gel, resulting in a mixture of two acetylenic acetogenins which were purified using HPLC procedures. Analysis of 1H NMR spectra and 13C, as well as MS allowed the identification of 2-(eicos-11-yn-19-enyl)-3-hydroxy-4-methyl-?-lactone (I) and 2-(eicos-11-ynyl)-3-hydroxy-4-metil-? lactone (II). To establish relationships between the chemical structure / biological activity, the mixture of I and II was completely hydrogenated generating 2-eicosyl-3-hydroxy-4-methyl-?-lactone (III). The cytotoxicity of the compounds I and II was evaluated in vitro against various lineages of cancer cells, including murine (melanoma - B16F10Nex2) and human (breast - SKBR-3; ovary - Ovcar-3; cervix - Siha, colon and rectum - HCT ; Melanoma - A2058). The activity of the mixture of I + II is higher than the potential detected in the pure substances (IC50 values ranging from 21.0±0.3 to 28±1 ?g/mL). The compound I showed moderate potential against HCT and lines OVCAR-3 (IC50 of 83±3 and 81.0±0.1 ?g/mL), whereas compound II showed a reduced potential (IC50> 90 ?g/mL for all cells tested). These results suggest that the presence of a terminal double bond in the side chain could play a relavant role in the cytotoxic activity. Similarly, compound III was inactive (IC50> 100 ?g/mL for all tested cells) indicating that the presence of the triple bond in the side chain is also important to that potential.
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    Desreplicação molecular de espécies vegetais, simplificação e análise farmacocinética in vitro de análogos de licarina-a como protótipo de potenciais antiparasitários e antitumorais
    (Universidade Federal de São Paulo (UNIFESP), 2018-09-14) Morais, Thiago Rahal [UNIFESP]; Lago, João Henrique Ghilardi [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    In the following work, the cytotoxic and antiparasitic activities were evaluated as well as the molecular dereplication (by HPLC and NMR) of the hexanic and methanolic extracts of different Piper plants (P. arboreum, P. solmnsianum, P. cernuum, P. gaudichaudianum, P. aduncum, P. umbellatum and P. regnellii). Among the extracts studied, those belonging to the species P. cernuum were selected for a biomonitoring chemical study, since the leaf and branch extracts presented cytotoxic and antiparasitic potential. From this process, three lignans (cubebin, hinokinin and kusunokinin) were isolated from the leaves, the latter two occurring for the first time in the species. From the branches was isolated and characterized the bornyl p-coumarate as bioactive compound, whose occurrence is being described for the first time in the species. In addition to these active compounds, two inactive sesquiterpenes were obtained (epi-dihydroagarofuran and 11-hydroxy-4,5-secoeudesman-4,5-dione), also described for the first time in the species. In addition, extracts from the leaves of P. regnellii were submitted to chromatographic fractionation biomonitored by the antiparasitary and cytotoxic activities evaluation from which the neolignan licarin A was isolated and identified. From this bioactive compound and aiming the establishment of SAR (six structures were prepared from methylation, acetylation, allylation, Claisen-like and iodocyclization reactions that were tested for their antiparasitic and cytotoxic activities. In advance of this study, simpler structures were planned with the aim of molecular optimization, maintaining the characteristics of the pharmacophore present in the licarin A derivatives (eugenol, isoeugenol, vanillin and vanillic alcohol) and meeting the initial parameters of pharmacokinetics (ADME), especially in the absorption aspect (A). Thus, in vitro models of permeability of the gastro-intestinal tract and blood-brain barrier (PAMPA-GIT / BBB) and tissue permeability of the intestinal membrane of CD-1 mice (ex vivo model) were performed using the Ussing method. The simpler analogues were easier to permeate the membranes of the various models due to the lower partition coefficient compared to the licarin A derivatives (log P ≥ 4), a major factor required in the development of new drugs. The 2-allyl derivative of licarin-A exhibited higher activity against T. cruzi trypomastigotes with EC50 = 5.0 μM. In contrast, the 2-allylated derivative of isoeugenol presented values of EC50 = 21.2 and 10.4 μM for trypomastigote and amastigote forms, respectively. We concluded that the 2-allyl-isoeugenol analogue maintained the cytotoxic characteristics for tumor and antiparasitic lines indicating the structural particularity and importance attributed to the phenolic and propenyl groups present, in addition to having greater effectiveness in the permeability which makes this compound a good prototype for future studies of new molecular optimization and in vivo assays.
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    Estudo do extrato das folhas modificadas de Euphorbia tirucalli - Desreplicação e potencial antitumoral
    (Universidade Federal de São Paulo, 2022-12-08) Russo, Daniela Cristina [UNIFESP]; Sartorelli, Patricia [UNIFESP]; http://lattes.cnpq.br/6836392358779448; http://lattes.cnpq.br/7680593463616394
    Euphorbia tirucalli L., the plant selected for this research, has been popularly used to combat tumors, arousing the interest of researchers in the area of Chemistry of Natural Products. Therefore, the present study aimed to evaluate the cytotoxic activity for estrogen-positive breast adenocarcinoma (MCF-7) and anaplastic thyroid cancer (HTH83) provided by the compounds present in the methanolic extract obtained from the modified leaves. The plant was collected in the municipality of Praia Grande. After drying and grinding, chromatographic techniques were used to separate the secondary metabolites. Spectroscopic and spectrometric techniques were used to dereplicate the partitions obtained from the crude extract. The methanolic extract was used to obtain the liquid-liquid partitions with solvents of increasing polarity, hexane, dichloromethane, ethyl acetate and butanol. Due to its chemical profile, the dichloromethane partition was chosen to obtain and analyze fractions and sub-fractions. The results obtained by GC-MS and analysis by 1H and 13C NMR allowed the identification of euphol, lanosterol and tirucallol, three tetracyclic triterpenes, lupenone and lupeol, two pentacyclic triterpenes. The data obtained by LC-MS/MS in association with the Global Natural Products Social Networking (GNPS) platform allowed the annotation of fourteen substances, namely: α-adenosine; 2,3-dihydroxypropyl hexadecanoate; 13-docosenamide, (Z); chlorogenic acid; conjugated linoleic acid; palmitoleic acid; arantiamide; austinoneol; acetyl tributyl citrate; loliolide; N-fructosyl phenylalanine; N-fructosyl isoleucine; oleamide and uvaol, the latter being another pentacyclic triterpene. Cell viability assays and the calculation of the 50% effective concentration (IC50) in MCF-7 and HTH83 tumor cell lines showed promising activity, with particularly special results for sub-fractions ETD-5C2 (mixture containing lupeol) and ETD-7C2 (mixture containing eufol and tirucallol). In the first, the cytotoxic activity for HTH83 after 72 h of incubation showed IC50 equal to 9.843 µg mL-1 and in the second, the cytotoxic activity for MCF-7 after 24 h of incubation showed IC50 equal to 20.45 µg mL-1. Due to the absence in the literature of studies on thyroid cancer with the Euphorbia tirucalli species, the results of this study are complementary to recently published works and contribute to the understanding of the species and the cytotoxic activity of its metabolites.
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    Isolamento, caracterização estrutural e avaliação do potencial farmacológico de metabólitos especiais das folhas de Schinus terebinthifolius (Anacardiaceae)
    (Universidade Federal de São Paulo, 2014-09-09) Morais, Thiago Rahal [UNIFESP]; Lago, João Henrique Ghilardi [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The present work was performed a bioguided phytochemical study by antiparasitic and cytotoxic activities of extracts from leaves of Schinus terebinthifolius Raddi (Anarcadiaceae). Initially, this extract showed in vitro cytotoxic potential against the murine melanoma cell line B16F10-Nex2 (IC50 of 82 ± 5g/mL) and antiparasitic activity against amastigotes and promastigotes of Leishmania infantum (100% killing 300g/mL) and Trypanosoma cruzi trypomastigotes (90% kill at 300g/mL). After partition, it was found that the activities were concentrated in the hexane phase which underwent successive purification procedures (silica gel and Sephadex LH-20) fully monitored by bioassay. Thus, two triterpenes were isolated bioactive tirucalanes, whose structures were defined as the (Z)-masticadienoic acid (1) and (Z)-schinol (2) after NMR analysis. After isolation, the compounds 1 and 2 were evaluated against different human tumor cell lines (A2058: melanome, HeLa: cervical carcinome, HCT: colon tumor; SKBR-3: breast cancer and U87: glioblastome) whose IC50 values ranged between > 150-32 ± 3g/mL, being the most active compound 2. With regard to the antiparasitic activity, the results showed that compound 1 is inactive against the promastigotes of L. infantum but has moderate activity for amastigotes with IC50 of 66.51 g/mL compared to positive control (miltefosine - EC50 of 7.25g/mL). Regarding the compound 2, also lack of activity against promastigostes and weak forms potential against amastigotes of L. infantum (EC50 97.59g/mL) was observed. When the two compounds were evaluated for activity against T. cruzi trypomastigotes, it was observed that 1 is inactive (EC50 > 150g/mL) while excellent potential was detected for 2 with EC50 of 16.28g/mL, compared to standard drug (benznidazole) whose EC50 value was determined to be 114.68g/mL. Compounds 1 and 2 showed reduced toxicity front NCTC the cells with CC50 values of > 200 and 95.49g/mL, respectively. In order to establish correlations chemical/biological activity of eight derivatives structure based on the structure 1 by acetylation and reduction reactions of the carbonyl group at C-3, methylation of the carboxylic acid (C-27) were prepared, and hydrogenation of double bond at C-24. After evaluation of the cytotoxic activity was observed that the reduced and acetylated at C-3 substance was best presented result against the human strains tested with IC50 values ranging from 11 ± 1 to 17 ± 1g/mL. Regarding the antiparasitic activity was detected that all semisynthetic derivatives are less active than the natural products 1 and 2, indicating that the presence of the hydroxyl group at C-3 is essential for antitrypanosomal activity while the carbonyl group in the same position is important for potential antileishmanial. Based on the results obtained, it can be inferred that the triterpenes 1 and 2, isolated from S. terebinthifolius can be used as a prototype for the development of new drugs for cancer treatment, as well as the Chagas disease and leishmaniasis.