RESUMO
Chemical scaffolds of natural products have historically been sources of inspiration for the development of novel molecules of biological relevance, including hit and lead compounds. To identify new compounds active against Trypanosoma cruzi, we designed and synthesized 46 synthetic derivatives based on the structure of two classes of natural products: tetrahydrofuran lignans (Series 1) and oxazole alkaloids (Series 2). Compounds were screened in vitro using a cellular model of T. cruzi infection. In the first series of compounds, 11 derivatives of hit compound 5 (EC50 = 1.1 µM) were found to be active; the most potent (7, 8, and 13) had EC50 values of 5.1-34.2 µM. In the second series, 17 analogs were found active at 50 µM; the most potent compounds (47, 49, 59, and 63) showed EC50 values of 24.2-49.1 µM. Active compounds were assessed for selectivity, hemocompatibility, synergistic potential, effects on mitochondrial membrane potential, and inhibitory effect on trypanothione reductase. All active compounds showed low toxicity against uninfected THP-1 cells and human erythrocytes. The potency of compounds 5 and 8 increased steadily in combination with benznidazole, indicating a synergistic effect. Furthermore, compounds 8, 47, 49, 59, and 63 inhibited parasitic mitochondria in a dose-dependent manner. Although increased reactive oxygen species levels might lead to mitochondrial effects, the results indicate that the mechanism of action of the compounds is not dependent on trypanothione reductase inhibition. In silico calculation of chemical descriptors and principal component analysis showed that the active compounds share common chemical features with other trypanocidal molecules and are predicted to have a good ADMET profile. Overall, the results suggest that the compounds are important candidates to be further studied for their potential against T. cruzi.
Assuntos
Produtos Biológicos/farmacologia , Desenho de Fármacos , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Alcaloides/síntese química , Alcaloides/química , Alcaloides/farmacologia , Produtos Biológicos/síntese química , Produtos Biológicos/química , Relação Dose-Resposta a Droga , Furanos/síntese química , Furanos/química , Furanos/farmacologia , Humanos , Lignanas/síntese química , Lignanas/química , Lignanas/farmacologia , Estrutura Molecular , Oxazóis/síntese química , Oxazóis/química , Oxazóis/farmacologia , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Tripanossomicidas/síntese química , Tripanossomicidas/químicaRESUMO
The marine sponge Raspailia bouryesnaultae, collected in South Brazil, was selected for detailed investigation considering the results of a screening that pointed to an in vitro antiproliferative effect against non-small cells of human lung cancer (A549) and anti-herpes activity against Herpes Simplex virus type 1 (KOS and 29R strains) of ethanolic extracts. The fractionation and chemical investigation of the sponge's hexanic fraction led to the isolation and structural elucidation of six clerodane diterpenes. The main component was identified as the already-reported raspailol (1), isolated from a sponge of the same genus collected in New Zealand. The structure of a new diterpene (2) with a rearranged skeleton was established by high-resolution mass spectrometry (HRMS) and 1D and 2D Nuclear magnetic resonance spectroscopy (NMR) experiments, and named here as raspadiene. Furthermore, four diterpenes were elucidated as isomers of clerodane diterpenes previously obtained from plants, namely kerlinic acid (3), kerlinic acid methyl ester (4), annonene (5), and 6-hydroxyannonene (6). They differ in their stereochemistry, since these diterpenes are characterized by a trans ring fusion at the decalin moiety and the relative configuration of the two methyl groups at C-8 and C-9 in a cis relationship (type trans/cis). The Raspailia diterpenes have a cis ring fusion at the decalin moiety, and the two methyl groups at C-8 and C-9 are in a trans relationship (type cis/trans). The isolated compounds were evaluated for their potential antiproliferative effects on human cancer cell line A549, and it was observed that the diterpenes bearing a hydroxyl group at C-6 exhibited moderate cytotoxic activity, with 50% inhibitory concentration (IC50) values lower than 25 µM. The evaluation of the potential anti-herpes activity against Herpes Simplex Virus type 1 (HSV-1, KOS and 29R strains) showed that the more promising results were observed for the new compound 2, since it inhibited HSV-1 (KOS and 29R strains) replication by 83% and 74%, respectively.
Assuntos
Antineoplásicos/farmacologia , Antivirais/farmacologia , Diterpenos Clerodânicos/farmacologia , Poríferos/química , Células A549 , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antivirais/química , Antivirais/isolamento & purificação , Brasil , Proliferação de Células/efeitos dos fármacos , Diterpenos Clerodânicos/química , Diterpenos Clerodânicos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Herpesvirus Humano 1 , Humanos , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Estereoisomerismo , Replicação Viral/efeitos dos fármacosRESUMO
BACKGROUND AND PURPOSE: Antibiotic resistance is now a worldwide public health problem. A potential alternative source in the search for new antibiotics is the bioactive molecules obtained from marine products, as the halistanol trisulfate, obtained from Petromica citrina, and herein investigated from its antimicrobial and anti-inflammatory properties. EXPERIMENTAL APPROACH: The antimicrobial activity of the fractionation products (TSH fraction, halistanol sulfate (HS) and halistanol sulfate C (HS-C)) of the marine sponge Petromica citrina was evaluated against twenty bacteria and two fungi strains by the disk diffusion and microdilution methods. After initial in vitro tests, an in vivo assay was proposed, to evaluate survival and inflammatory parameters in an animal model of peritonitis mediated by MRSA. The animals are treated with TSH fraction (1, 2.5 and 5 mg kg-1) or Vancomycin (30 mg kg-1) twice (6 and 18 h after induction) until organ removal for evaluation of the inflammatory profile, or for 3 days, 12 h each (6 h, 18 h, 30 h, 42 h, 54 h and 66 h after induction) in animals which were followed-up for by five days, for the evaluation of survival. KEY RESULTS: The BF fraction, TSH fraction, HS and HS-Cinhibited, in vitro, the Enterococcus faecalis, Staphylococcus aureus and Candida albicans growth. Moreover, these samples were effective against S. aureus (MSSA), MRSA and Vancomycin-Resistence Enterococcus (VRE). The in vivo results demonstrated that TSH fraction reduced mortality when compared to the saline group. To evaluate the role of inflammation in outcomes of peritonitis, cytokines (IL-1ß, IL-6, TNF-α) and MPO activity were measured. In general, anti-inflammatory activity was detected in animals treated with TSH in different doses. CONCLUSION AND IMPLICATIONS: These data suggest that TSH may be an interesting alternative for the treatment infections by Gram-positive resistant bacteria, due to its antimicrobial profile associated with its anti-inflammatory properties.
Assuntos
Produtos Biológicos/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Poríferos/química , Sepse/tratamento farmacológico , Sepse/microbiologia , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Produtos Biológicos/administração & dosagem , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Fracionamento Químico , Interleucina-1beta/sangue , Interleucina-6/sangue , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Peroxidase/metabolismo , Sepse/sangue , Fator de Necrose Tumoral alfa/sangueRESUMO
In this study we report the synthesis, characterization, biological evaluation, and druglikeness assessment of a series of 20 novel isoxazolyl-sulfonamides, obtained by a four-step synthetic route. The compounds had their activity against Trypanosoma cruzi, Leishmania amazonensis, Herpes Simplex Virus type 1 and cytotoxicity evaluated in phenotypic assays. All compounds have drug-like properties, showed low cytotoxicity and were promising regarding all other biological activities reported herein, especially the inhibitory activity against T. cruzi. The compounds 8 and 16 showed significant potency and selectivity against T. cruzi (GI50â¯=â¯14.3⯵M, SIâ¯>â¯34.8 and GI50â¯=â¯11.6⯵M, SIâ¯=â¯29.1, respectively). These values, close to the values of the reference drug benznidazole (GI50â¯=â¯10.2⯵M), suggest that compounds 8 and 16 represent promising candidates for further pre-clinical development targeting Chagas disease.
Assuntos
Antivirais/farmacologia , Isoxazóis/farmacologia , Sulfonamidas/farmacologia , Tripanossomicidas/farmacologia , Animais , Antivirais/síntese química , Antivirais/química , Antivirais/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Humanos , Isoxazóis/síntese química , Isoxazóis/química , Isoxazóis/toxicidade , Leishmania/efeitos dos fármacos , Estrutura Molecular , Simplexvirus/efeitos dos fármacos , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Sulfonamidas/toxicidade , Tripanossomicidas/síntese química , Tripanossomicidas/química , Tripanossomicidas/toxicidade , Trypanosoma cruzi/efeitos dos fármacos , Células VeroRESUMO
The aim of this study was to investigate the sedative activity of the aqueous leaf extract of Passiflora quadrangularis, a species that is widely cultivated and consumed in South America, and to identify its main constituents and elucidate the involvement of the GABAergic pathway in its mechanism of action. The bioguided fractionation of the crude extract showed a positive relationship between the sedative activity of the extract and its flavonoids. The methods employed to identify and isolate its main flavonoids resulted in the identification of vitexin-2''-O-xyloside, vitexin-2''-O-glucoside, orientin-2''-O-xyloside and orientin-2''-O-glucoside. Vitexin-2"-O-xyloside, the major flavonoid of the extract, showed sedative activity after oral administration in mice.
Assuntos
Flavonoides/farmacologia , Neurônios GABAérgicos/fisiologia , Hipnóticos e Sedativos/farmacologia , Passiflora , Extratos Vegetais/farmacologia , Ácido gama-Aminobutírico/fisiologia , Animais , Diazepam/farmacologia , Relação Dose-Resposta a Droga , Flavonoides/isolamento & purificação , Moduladores GABAérgicos/farmacologia , Neurônios GABAérgicos/efeitos dos fármacos , Hipnóticos e Sedativos/isolamento & purificação , Masculino , Camundongos , Extratos Vegetais/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologiaRESUMO
Non-small cell lung cancer (NSCLC) is one of the most common malignant tumors, with a high mortality rate due to the elevated risk of resistance. Natural cucurbitacins and their derivatives are recognized as promising antitumor compounds for several types of cancer, including NSCLC. In a recent study published by our research group, DACE (2-deoxy-2-amine-cucurbitacin E), which is a semisynthetic derivative of cucurbitacin B, showed potential in vitro synergistic antiproliferative effects combined with paclitaxel (PTX) in A549 cells. In sequence, the purpose of this study was to evaluate the in vivo antitumor efficacy of this combined therapy as well as with these drugs individually, using a human NSCLC xenograft model. Some indicators of sub chronic toxicity that could be affected by treatments were also assessed. The results obtained in vivo with the combined treatment (1mg/kg+PTX 10mg/kg) showed the most effective reduction of the relative tumor volume and the highest inhibition of tumor growth and proliferation, when compared with those of the single treatments. Furthermore, scintigraphic images, obtained before and after the treatments, showed that the most effective protocol able to reduce the residual viable tumor mass was the combined treatment. All treatment regimens were well tolerated without significant changes in body weight and no histological and functional damage to liver and kidney tissues. These results corroborate our previous in vitro synergistic effects published. Taken together, these insights are novel and highlight the therapeutic potential of DACE and PTX combination scheme for NSCLC.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Triterpenos/farmacologia , Células A549 , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Antígeno Ki-67/metabolismo , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Paclitaxel/toxicidade , Compostos Radiofarmacêuticos/administração & dosagem , Fatores de Tempo , Testes de Toxicidade Subcrônica , Triterpenos/toxicidade , Carga Tumoral/efeitos dos fármacos , Imagem Corporal Total , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Chagas disease and leishmaniasis are neglected tropical diseases (NTDs) endemic in developing countries. Although there are drugs available for their treatment, efforts on finding new efficacious therapies are continuous. The natural lignans grandisin (1) and veraguensin (2) show activity against trypomastigote T. cruzi and their scaffold has been used as inspiration to design new derivatives with improved potency and chemical properties. We describe here the planning and microwave-irradiated synthesis of 26 isoxazole derivatives based on the structure of the lignans 1 and 2. In addition, the in vitro evaluation against culture trypomastigotes and intracellular amastigotes of T. cruzi and intracellular amastigotes of L. amazonensis and L. infantum is reported. Among the synthesized derivatives, compounds 17 (IC50 = 5.26 µM for T. cruzi), 29 (IC50 = 1.74 µM for T. cruzi) and 31 (IC50 = 1.13 µM for T. cruzi and IC50 = 5.08 µM for L. amazonensis) were the most active and were also evaluated against recombinant trypanothione reductase of T. cruzi in a preliminary study of their mechanism of action.
Assuntos
Antiprotozoários/química , Antiprotozoários/farmacologia , Desenho de Fármacos , Isoxazóis/química , Leishmania infantum/efeitos dos fármacos , Leishmania mexicana/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Trypanosoma cruzi/efeitos dos fármacos , Animais , Furanos/farmacologia , Isoxazóis/farmacologia , Leishmania infantum/crescimento & desenvolvimento , Leishmania mexicana/crescimento & desenvolvimento , Leishmaniose/parasitologia , Lignanas/farmacologia , Estrutura Molecular , NADH NADPH Oxirredutases/antagonistas & inibidores , NADH NADPH Oxirredutases/metabolismo , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Trypanosoma cruzi/crescimento & desenvolvimentoRESUMO
ABSTRACT Several species of the genus Passiflora are distributed all over South America, and many of these species are used in popular medicine, mainly as sedatives and tranquilizers. This study analyzes the chemical profile of extracts of four Passiflora species used in folk medicine, focusing on the flavonoids, alkaloids and saponins. We employed simple and fast fingerprint analysis methods by high performance liquid chromatography, ultra performance liquid chromatography and capillary electrophoresis techniques. The analysis led to the detection and identification of C-glycosylflavonoids in all the plant extracts, these being the main constituents in P. tripartita var. mollissima and P. bogotensis. Saponins were observed only in P. alata and P. quadrangularis, while harmane alkaloids were not detected in any of the analyzed extracts in concentrations higher than 0.0187 ppm, the detection limit determined for the UPLC method.
RESUMO
Cucurbitacins and their derivatives are triterpenoids that are found in various plant families, and are known for their pharmacological and biological activities, including anti-cancer effects. Lung cancer represents a major public health problem, with non-small-cell lung cancer (NSCLC) being the most frequent and aggressive type of lung cancer. The objective of this work was to evaluate four cucurbitacins (CUCs) for their cytotoxic activity, effects on apoptosis induction, cell cycle progression, anti-migratory, and anti-invasive effects on the human NSCLC cell line (A549 cells). Our findings showed that these CUCs could suppress human NSCLC cell growth in vitro through their effects on the PI3Kinase and MAPK pathways, which lead to programmed cell death induction, as well as inhibition of cell migration and cell invasion. Additionally, these effects culminate in apoptosis induction and G2/M cell cycle arrest by modulating cyclin B1 expression, and in the mitigation of strategic steps of lung cancer metastasis, including migration and invasion of A549 cells. These results suggest that two natural (DDCB and CB) and two novel semisynthetic derivatives of cucurbitacin B (ACB and DBCB) could be considered as promising compounds with antitumor potential.
Assuntos
Apoptose/efeitos dos fármacos , Cucurbitacinas/farmacologia , Cucurbitacinas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Células A549 , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cucurbitacinas/química , Ciclina B1/metabolismo , Regulação para Baixo/efeitos dos fármacos , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Humanos , Neoplasias Pulmonares/enzimologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Invasividade Neoplásica , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologiaRESUMO
Several studies have shown the potential use of Ilex paraguariensis in developing products with the aim to protect biological systems against oxidative stress-mediated damages. In the same way, technological studies have demonstrated the feasibility of obtaining dry products, by spray-drying process, from aqueous extracts of I. paraguariensis in laboratory. The present work was designed to develop pellets by extrusion/spheronization process, from an I. paraguariensis spray-dried powder. The pellets were characterized with respect to their chemical, physical, and technological properties, and the thermal and the photostability of the main polyphenol constituents were investigated. The pellets exhibited adequate size, shape, and high process yield (78.7%), as well as a good recovery of the total polyphenols (>95%) and a good dissolution in water (89.44 to 100.05%). The polyphenols were stable against light when conditioned in amber glass bottles; unstable against heat when the samples were conditioned either in open glass bottles or in hermetically sealed glass bottles and demonstrated to be hygroscopic and sensible to the temperature, especially when stored in permeable flasks. These findings pointed to the relevance of reducing the residual moisture content of pellets as well as of conditioning them in opaque humidity tight packages under low temperatures. The feasibility of obtaining pellets from an I. paraguariensis spray-dried powder using extrusion/spheronization technique was, for the first time, demonstrated. This finding represents a novelty for the herbal products in both pharmaceutical and food fields.
Assuntos
Implantes de Medicamento/química , Ilex paraguariensis/química , Extratos Vegetais/química , Química Farmacêutica/métodos , Estabilidade de Medicamentos , Umidade , Tamanho da Partícula , Ácidos Polimetacrílicos/química , Polifenóis/química , Pós/química , Solubilidade , Tecnologia Farmacêutica/métodos , TemperaturaRESUMO
Nonsmall cell lung cancer (NSCLC) represents an important cause of mortality worldwide due to its aggressiveness and growing resistance to currently available therapy. Cucurbitacins have emerged as novel potential anticancer agents showing strong antiproliferative effects and can be promising candidates for combined treatments with clinically used anticancer agents. This study investigates the synergistic antiproliferative effects of a new semisynthetic derivative of cucurbitacin B (DACE) with three chemotherapy drugs: cisplatin (CIS), irinotecan (IRI), and paclitaxel (PAC) on A549 cells. The most effective combinations were selected for studies of the mechanism of action. Using an in silico tool, DACE seems to act by a different mechanism of action when compared with that of different classes of drugs already used in clinical settings. DACE also showed potent synergic effects with drugs, and the most potent combinations induced G2/M cell cycle arrest by modulating survivin and p53 expression, disruption of F-actin cytoskeleton, and cell death by apoptosis. These treatments completely inhibited the clonogenic potential and did not reduce the proliferation of nontumoral lung cells (MRC-5). DACE also showed relevant antimigratory and anti-invasive effects, and combined treatments modulated cell migration signaling pathways evolved with metastasis progression. The effects of DACE associated with drugs was potentiated by the oxidant agent l-buthionine-sulfoximine (BSO), and attenuated by N-acetilcysteine (NAC), an antioxidant agent. The antiproliferative effects induced by combined treatments were attenuated by a pan-caspase inhibitor, indicating that the effects of these treatments are dependent on caspase activity. Our data highlight the therapeutic potential of DACE used in combination with known chemotherapy drugs and offer important insights for the development of more effective and selective therapies against lung cancer.
Assuntos
Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Triterpenos/farmacologia , Actinas/metabolismo , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Camptotecina/análogos & derivados , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Irinotecano , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Survivina , Triterpenos/química , Triterpenos/uso terapêutico , Proteína Supressora de Tumor p53/metabolismoRESUMO
In this study, we applied a gradient High-Speed Counter-Current Chromatography (HSCCC) method that allowed, by direct injection of an aqueous crude extract of the leaves of Passiflora bogotensis, the successful isolation of six flavonoids in a single run, with purity of each compound higher than 81%. This separation enabled the isolation of two new flavonoid glycosides, apigenin-6-C-α-l-rhamnopyranosyl-(1â2)-(6â³-O-acetyl)-ß-d-glucopyranoside (2) and luteolin-6-C-α-l-rhamnopyranosyl-(1â2)-(6â³-O-acetyl)-ß-d-glucopyranoside (4), and four known ones, isovitexin (1), isoorientin (3), isovitexin-2â³-O-rhamnoside (5) and isoorientin-2â³-O-rhamnoside (6). The structures of the isolated compounds were identified by HPLC-DAD, LC-MS, (1)H and (13)C NMR and comparison with literature data. The inhibitory activities of all of these compounds were evaluated in vitro on α-glucosidase from S. cerevisiae, and the IC50 was determinate. This is the first study concerning the chemical composition and biological activity of Passiflora bogotensis.
Assuntos
Distribuição Contracorrente/métodos , Flavonoides/análise , Inibidores de Glicosídeo Hidrolases/análise , Glicosídeos/análise , Passiflora/química , Extratos Vegetais/química , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/farmacologia , Glicosídeos/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Folhas de Planta/química , alfa-Glucosidases/efeitos dos fármacosRESUMO
The n-butanol fraction (BF) obtained from the crude extract of the marine sponge Petromica citrina, the halistanol-enriched fraction (TSH fraction), and the isolated compounds halistanol sulfate (1) and halistanol sulfate C (2), were evaluated for their inhibitory effects on the replication of the Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the viral plaque number reduction assay. The TSH fraction was the most effective against HSV-1 replication (SI = 15.33), whereas compounds 1 (SI = 2.46) and 2 (SI = 1.95) were less active. The most active fraction and these compounds were also assayed to determine the viral multiplication step(s) upon which they act as well as their potential synergistic effects. The anti-HSV-1 activity detected was mediated by the inhibition of virus attachment and by the penetration into Vero cells, the virucidal effect on virus particles, and by the impairment in levels of ICP27 and gD proteins of HSV-1. In summary, these results suggest that the anti-HSV-1 activity of TSH fraction detected is possibly related to the synergic effects of compounds 1 and 2.
Assuntos
Antivirais/química , Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Poríferos/química , Esteróis/química , Esteróis/farmacologia , 1-Butanol/química , Animais , Brasil , Linhagem Celular , Chlorocebus aethiops , Células Vero , Ensaio de Placa Viral/métodosRESUMO
The leaf extracts of many species of genus Passiflora have been extensively investigated for their biological activities on several rat tissues, but mainly in the central nervous system and liver. They posses anxiolytic-like, sedative effects and antioxidant properties. Evidences suggest a key role of C-glycosylflavonoids in the biological activities of Passiflora extracts. Some species (such as P. manicata) of the genus are still poorly investigated for their chemical and biological activity. In this work, we aim to investigate both antioxidant and antiglycation properties of aqueous extract of P. manicata leaves (PMLE) in vitro and ex vivo models. Crude extract showed the C-glycosylflavonoid isovitexin as the major compound. Isoorientin and vitexin were also identified. In TRAP/TAR assay, PMLE showed a significant antioxidant activity. PMLE at concentrations of 10 and 100 µg mL⻹ significantly decreasing LDH leakage in rat liver slices. Antioxidant effect also was observed by decreased in oxidative damage markers in slices hence hydrogen peroxide was added as oxidative stress inductor. PMLE inhibited protein glycation at all concentrations tested. In summary, P. manicata aqueous leaf extract possess protective properties against reactive oxygen species and also protein glycation, and could be considered a new source of natural antioxidants.
Assuntos
Antioxidantes/farmacologia , Passiflora/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Espécies Reativas de Oxigênio/metabolismo , Animais , Apigenina/farmacologia , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Luteolina/farmacologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Carbonilação Proteica , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/análiseRESUMO
This manuscript describes the evaluation of anti-infective potential in vitro of organic extracts from nine sponges, one ascidian, two octocorals, one bryozoan, and 27 seaweed species collected along the Brazilian coast. Antimicrobial activity was tested against Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922) and Candida albicans (ATCC 10231) by the disk diffusion method. Antiprotozoal activity was evaluated against Leishmania braziliensis (MHOM/BR/96/LSC96-H3) promastigotes and Trypanosoma cruzi (MHOM/BR/00/Y) epimastigotes by MTT assay. Activity against intracellular amastigotes of T. cruzi and L. brasiliensis in murine macrophages was also evaluated. Antiviral activity was tested against Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the plaque number reduction assay (IC50). Cytotoxicity on VERO cells was evaluated by the MTT assay (CC50). The results were expressed as SI = CC50/IC50. The most promising antimicrobial results were obtained against S. aureus and C. albicans with Dragmacidon reticulatum. Among the seaweeds, only Osmundaria obtusiloba showed moderate activity against P. aeruginosa. Concerning antiprotozoal activity, Bugula neritina, Carijoa riseii, Dragmaxia anomala and Haliclona (Halichoclona) sp. showed the most interesting results, mainly against extracellular promastigote forms of L. braziliensis (66, 35.9, 97.2, and 43.6% inhibition, respectively). Moreover, six species of seaweeds Anadyomene saldanhae, Caulerpa cupressoides, Canistrocarpus cervicornis, Dictyota sp., Ochtodes secundiramea, and Padina sp. showed promising results against L. braziliensis (87.9, 51.7, 85.9, 93.3, 99.7, and 80.9% inhibition, respectively), and only Dictyota sp. was effective against T. cruzi (60.4% inhibition). Finally, the antiherpes activity was also evaluated, with Haliclona (Halichoclona) sp. and Petromica citrina showing the best results (SI = 11.9 and SI > 5, respectively). All the active extracts deserve special attention in further studies to chemically characterize the bioactive compounds, and to perform more refined biological assays.
Assuntos
Antozoários/química , Antibacterianos , Antiprotozoários , Citotoxinas , Poríferos/química , Alga Marinha/química , Urocordados/química , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Antiprotozoários/farmacologia , Bactérias/crescimento & desenvolvimento , Brasil , Chlorocebus aethiops , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Leishmania braziliensis/crescimento & desenvolvimento , Trypanosoma cruzi/crescimento & desenvolvimento , Células VeroRESUMO
Cucurbitacins are secondary metabolites that mediate insect plant interactions not only as allomones against generalists but also as kairomones for specialist herbivores. This study was undertaken to identify the potential of cucurbitacin derivatives as insect antifeedant agents. The antifeedant capacity against a Cucurbitaceae specialist [ Epilachna paenulata (Coleoptera: Coccinellidae)] and a polyphagous insect [ Pseudaletia adultera (Lepidoptera: Noctuidae)] was evaluated in preference tests in which the insects were given a choice between food plants either treated with the cucurbitacin derivatives or treated with the solvent. The activity was found not to be related to the basic cucurbitacin skeleton, as only 15 of the 28 tested cucurbitacin derivatives were active. Only one of the tested compounds was phagostimulant to the specialist insect (the hemissuccinate of 16-oxo-dihydrocucurbitacin B derivative), while all other active derivatives were deterrent against one of the insects (13 compounds) or both of them (3 compounds). Changes in ring A of the cucurbitacins, as well as in the side chain, modified the activity. As a general trend, when chemical modifications of the basic structure produced a change in activity, the response was opposite in both insects used as biodetectors, indicating that a selective variation in the activity may be achieved by chemical modifications of the cucurbitacin skeleton.
Assuntos
Besouros/fisiologia , Cucurbitaceae/química , Cucurbitacinas/farmacologia , Lepidópteros/efeitos dos fármacos , Lepidópteros/fisiologia , Extratos Vegetais/farmacologia , Animais , Besouros/efeitos dos fármacos , Cucurbitacinas/química , Comportamento Alimentar/efeitos dos fármacos , Estrutura Molecular , Especificidade da EspécieRESUMO
OBJECTIVES: This paper aims to evaluate the anti-tumour properties of elatol, a compound (sesquiterpene) isolated from algae Laurencia microcladia. METHODS: In-vitro and in-vivo anti-tumour properties of elatol were investigated using: MTT assays to assess the cytotoxic effects; flow cytometry analysis to examine the cell cycle and apoptosis; Western blot analysis for determination of the expression of cell cycle and apoptosis proteins; and study of in-vivo tumour growth in mice (C57Bl6 mice bearing B16F10 cells). KEY FINDINGS: Elatol exhibited a cytotoxic effect, at least in part, by inducing cell cycle arrest in the G(1) and the sub-G(1) phases, leading cells to apoptosis. Western blot analysis demonstrated that elatol reduced the expression of cyclin-D1, cyclin-E, cyclin-dependent kinase (cdk)2 and cdk4. A decrease in bcl-xl and an increase in bak, caspase-9 and p53 expression was also observed. In the in-vivo experiment, treatment with elatol was able to reduce tumour growth in C57Bl6 mice. CONCLUSIONS: Elatol promotes a delay in the cell cycle, probably in the G(1)/S transition, activating the apoptotic process and this could be responsible, at least in part, for the in-vivo effects observed. Taken together, the in-vitro and in-vivo experiments suggested that elatol has anti-tumour properties. Further studies should be conducted to clarify the mechanism of action.
Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Laurencia/química , Neoplasias/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Compostos de Espiro/uso terapêutico , Animais , Antineoplásicos Fitogênicos/farmacologia , Caspase 9/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Ciclina E/metabolismo , Quinase 2 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Feminino , Humanos , Masculino , Melanoma/tratamento farmacológico , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/metabolismo , Extratos Vegetais/farmacologia , Compostos de Espiro/farmacologia , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
Two cucurbitacins, dihydrocucurbitacin B (1) and cucurbitacin B (2), which can be obtained in large amounts from the roots of Wilbrandia ebracteata and from the fruits of Luffa operculata, respectively, were used as starting materials for the preparation of a library of 29 semi-synthetic derivatives. The structural changes that were performed include the removal, modification or permutation of functional groups in rings A and B as well as in the side chain. All new semisynthetic compounds, as well as 1 and 2, were tested in vitro for their cytotoxic effects on non-small-cell lung cancer cells (A549 cells). Some of these compound displayed potent to moderate activity against A549 tumor cells, especially those cucurbitacin B derivatives which were modified at ring A.
Assuntos
Antineoplásicos/síntese química , Antineoplásicos/toxicidade , Triterpenos/química , Triterpenos/toxicidade , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cucurbitaceae/química , Frutas/química , Humanos , Luffa/química , Raízes de Plantas/química , Triterpenos/síntese químicaRESUMO
INTRODUCTION: Leaves and fruits of Passiflora species are widely used around the world in popular medicine, mainly as sedatives and tranquilisers. C-glycosyl flavonoids are the main components of these species. OBJECTIVE: To investigate the constituent patterns and to develop a chromatographic method for the characterisation of the C-glycosyl flavonoids profile of the extracts of the leaves and the pericarp of South American Passiflora species. METHODOLOGY: The chemical composition of extracts from the leaves and the fruits' pericarp of Passiflora edulis var. flavicarpa, P. edulis var. edulis, Passiflora alata, Passiflora tripartita var. mollissima, Passiflora quadrangularis, Passiflora manicata and Passiflora ligularis was evaluated for the presence of C-glycosyl flavonoids. Two separate HPLC methods were developed suitable for a diode array detector (DAD) and a MS detector. Separation by HPLC-DAD was achieved on a Luna C-18 column, using solvent A (tetrahydrofuran-isopropanol-acetonitrile) and solvent B (H3PO4 0.5%) in an isocratic elution mode. In the HPLC-MS, the components were separated on a Luna RP-18A column by a gradient elution (water-acetonitrile-formic acid). RESULTS: The presence of C-glycosyl flavonoids was identified in leaves and pericarp of P. edulis var. flavicarpa, P. alata, P. edulis var. edulis and P. tripartita var. molissima, but only in leaf extracts of P. quadrangularis and P. manicata and not at all in P. ligularis. The different species and varieties showed different major constituents. The C-glycosyl flavonoids identified more frequently were orientin, isoorientin, vitexin and isovitexin. CONCLUSION: The methods established are simple and can be used as a tool for the characterisation and quality control of pharmaceutical preparations containing these Passiflora extracts.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/análise , Glicosídeos/análise , Passiflora/química , Folhas de Planta/química , Flavonoides/química , Frutas/química , Geografia , Glicosídeos/química , Espectrometria de Massas/métodos , Estrutura Molecular , Passiflora/classificação , Reprodutibilidade dos Testes , Solventes/química , América do Sul , Especificidade da EspécieRESUMO
The growth inhibition of 12 native marine bacteria isolated from Aplysina sponge surfaces, the shell of a bivalve, and Phytagel immersed for 48 h in sea water were used as indicator of the antifouling activity of the extracts of 39 marine organisms (octocorals, sponges, algae, and zoanthid) collected in the Colombian Caribbean Sea and on the Brazilian coast (Santa Catarina). Gram-negative bacteria represented 75% of the isolates; identified strains belonged to Oceanobacillus iheyensis, Ochrobactrum pseudogrignonense, Vibrio campbellii, Vibrio harveyi, and Bacillus megaterium species and seven strains were classified at genus level by the 16S rRNA sequencing method. The extracts of the octocorals Pseudopterogorgia elisabethae, four Eunicea octocorals, and the sponges Topsentia ophiraphidites, Agelas citrina, Neopetrosia carbonaria, Monanchora arbuscula, Cliona tenuis, Iotrochota imminuta, and Ptilocaulis walpersii were the most active, thus suggesting those species as antifoulant producers. This is the first study of natural antifoulants from marine organisms collected on the Colombian and Brazilian coasts.