RESUMO
Nacobbus aberrans ranks among the "top ten" plant-parasitic nematodes of phytosanitary importance. It causes significant losses in commercial interest crops in America and is a potential risk in the European Union. The nematicidal and phytotoxic activities of seven plant extracts against N. aberrans and Solanum lycopersicum were evaluated in vitro, respectively. The chemical nature of three nematicidal extracts (EC50,48h ≤ 113 µg mL-1) was studied through NMR analysis. Plant extracts showed nematicidal activity on second-stage juveniles (J2): (≥87%) at 1000 µg mL-1 after 72 h, and their EC50 values were 71.4-468.1 and 31.5-299.8 µg mL-1 after 24 and 48 h, respectively. Extracts with the best nematicidal potential (EC50,48h < 113 µg mL-1) were those from Adenophyllum aurantium, Alloispermum integrifolium, and Tournefortia densiflora, which inhibited L. esculentum seed growth by 100% at 20 µg mL-1. Stigmasterol (1), ß-sitosterol (2), and α-terthienyl (3) were identified from A. aurantium, while 1, 2, lutein (4), centaurin (5), patuletin-7-ß-O-glucoside (6), pendulin (7), and penduletin (8) were identified from A. integrifolium. From T. densiflora extract, allantoin (9), 9-O-angeloyl-retronecine (10), and its N-oxide (11) were identified. The present research is the first to report the effect of T. densiflora, A. integrifolium, and A. aurantium against N. aberrans and chemically characterized nematicidal extracts that may provide alternative sources of botanical nematicides.
Assuntos
Antinematódeos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Solanum lycopersicum/efeitos dos fármacos , Animais , Antinematódeos/química , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Espectroscopia de Prótons por Ressonância Magnética , Tylenchoidea/efeitos dos fármacosRESUMO
BACKGROUND: Eight plant species from Oaxaca, some of them used in traditional medicine, were subjected to screening of several biological activities to provide data regarding their anticancer potential, although no scientific information is available about their pharmacological effects. MATERIALS AND METHODS: Methanol extracts from stems or roots of the eight plants were tested for antioxidant activity by the DPPH- method. Antimicrobial activity was determined using the agar diffusion method and the minimal inhibitory concentration (MIC) was obtained by broth dilution method. Antitopoisomerase activity was assessed using mutant strains of Saccharomyces cerevisiae JN362a, JN394, JN394t-1, JN394t2.4 and JN394t2-5. The mutagenic activity was evaluated using the Ames test (Salmonella typhimurium TA1535). RESULTS: No extract showed significant antioxidant activity. The best antimicrobial activity was observed for Salpianthus arenarius (MIC 56.25 µg/mL) and Lantana achyranthifolia (MIC 78.12 µg/mL) against Staphylococcus aureus. Extracts of Acalypha cuspidata, Alloispermum integrifolium and L. achyranthifolia stems showed antitopoisomerase II activity with JN394t-1 growth of -30.88±0.0%, -38.11±4.95%, and -70.97±12.02% respectively. Galium mexicanum stem extract showed antitopoisomerase I activity with growth of 35.31±6.36% on the same mutant strain. All plant extracts were non-mutagenic. Fractionation of A. cuspidata extract led to identification of two subfractions with antitopoisomerase I and II activity at 154µg/mL (Positive controls 50 and 100µg/mL). CONCLUSION: Methanol extracts of A. cuspidata, A. integrifolium, G. mexicanum, and L. achyranthifolia stems showed antitopoisomerase and non-mutagenic activities, and consequently could be promising as a source of anticancer drugs.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Caules de Planta/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Metanol/farmacologia , México , Testes de Sensibilidade Microbiana , Mutagênese/efeitos dos fármacos , Inibidores da Topoisomerase/farmacologiaRESUMO
Eleven oleanane-type saponins (1-11) have been isolated from Microsechium helleri and Sicyos bulbosus roots and were evaluated for their antifeedant, nematicidal and phytotoxic activities. Saponins {3-O-ß-D-glucopyranosyl (1â3)-ß-D-glucopyranosyl-2ß,3ß,16α,23-tetrahydroxyolean-12-en-28-oic acid 28-O-α-L-rhamnopyranosyl-(1â3)-ß-D-xylopyranosyl-(1â4)-[ß-D-xylopyranosyl-(1â3)]-α-L-rhamnopyranosyl-(1â2)-α-L-arabinopyranoside} (1), and {3-O-ß-D-glucopyranosyl-2ß,3ß,16α,23-tetrahydroxyolean-12-en-28-oic acid 28-O-α-L-rhamnopyranosyl-(1â3)-ß-D-xylopyranosyl-(1â4)-[ß-D-xylopyranosyl-(1â3)]-α-L-rhamnopyranosyl-(1â2)-α-L-arabinopyranoside} (2) were also isolated from M. helleri roots together with the two known compounds 3 and 4. Seven known structurally related saponins (5-11) were isolated from S. bulbosus roots. The structures of these compounds were established as bayogenin and polygalacic glycosides using one- and two-dimensional NMR spectroscopy and mass spectrometry. Compounds 7, 10, bayogenin (12) and polygalacic acid (13) showed significant (p<0.05) postingestive effects on Spodoptera littoralis larvae, compounds 5-11 and 12 showed variable nematicidal effects on Meloydogyne javanica and all tested saponins had variable phytotoxic effects on several plant species (Lycopersicum esculentum, Lolium perenne and Lactuca sativa). These are promising results in the search for natural pesticides from the Cucurbitaceae family.
Assuntos
Antinematódeos/isolamento & purificação , Antinematódeos/farmacologia , Cucurbitaceae/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Ácido Oleanólico , Saponinas/isolamento & purificação , Saponinas/farmacologia , Spodoptera/efeitos dos fármacos , Animais , Antinematódeos/química , Citotoxinas/química , Larva/efeitos dos fármacos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Raízes de Plantas/química , Saponinas/químicaRESUMO
The objective of this study was to investigate the effect of ascorbic acid (AA) on the in vitro cytotoxicity of cypermethrin (CM), and on glutathione (GSH) metabolism in rat hepatocytes. In vitro cell viability, lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) leakage were measured, as indicators of hepatic damage, at 1, 15 and 30 min of exposure to CM. Glutathione and the activities of glutathione-S-transferase (GST) and gamma glutamyl transpeptidase (gamma-GT) were also measured. CM hepatotoxicity increased in a time and dose-dependent manner. In the presence of 30 microM CM, ALT and AST also increased 49 and 130% (P < 0.05), respectively, indicating metabolic hepatocyte damage. AA (1 mM) was capable to preserve 100% of cell integrity and modulated ALT and AST. Furthermore, CM induced a 27% reduction in the endogenous antioxidant GSH, and increased 203% GST and 283% gamma-GT (P < 0.05), indicating an oxidative insult. The presence of AA showed chemopreventive capacity against CM, recovering 60% of GSH and a 54% decrease in gamma-GT activity. These results suggest that AA in a 1:33 (CM:AA) ratio can modulate up to 90% of the damage caused to the cells by CM. It also demonstrates that AA can act as a primary antioxidant and hepatoprotector in rat hepatocytes.
Assuntos
Ácido Ascórbico/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Piretrinas/efeitos adversos , Alanina Transaminase/antagonistas & inibidores , Alanina Transaminase/metabolismo , Animais , Ácido Ascórbico/fisiologia , Aspartato Aminotransferases/antagonistas & inibidores , Aspartato Aminotransferases/metabolismo , Sobrevivência Celular/fisiologia , Dimetil Sulfóxido/farmacologia , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Glutationa/antagonistas & inibidores , Glutationa/efeitos dos fármacos , Glutationa/fisiologia , Glutationa Transferase/antagonistas & inibidores , Glutationa Transferase/fisiologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/enzimologia , Hepatócitos/metabolismo , L-Lactato Desidrogenase , Fígado/citologia , Fígado/efeitos dos fármacos , Masculino , Perfusão , Piretrinas/antagonistas & inibidores , Piretrinas/farmacocinética , Ratos , Ratos Wistar , Fatores de Tempo , gama-Glutamiltransferase/metabolismoRESUMO
The objective of this study was to compare the antioxidant effect of ardisin and epigallocatechin 3-O-gallate (EGCG) in hepatocytes exposed to either benomyl or 1-nitropyrene (1-NP). Rat hepatocytes were incubated in a serum-free medium with non-cytotoxic concentrations of either ardisin (0.27 microg/ml) or EGCG (3 microg/ml), and with either benomyl (35 microg/ml) or 1-NP (0.25 microg/ml). The level of malondialdehyde (MDA) as a marker of lipid peroxidation was determined, as well as the content of glutathione (GSH) and the activities of glutathione peroxidase (GPx) and glutathione reductase (GR). In comparison to the control, the concentration of GSH improved 282% (P<0.05) and 260% (P<0.05) after the cells were pre-incubated with ardisin or EGCG and then exposed to benomyl, respectively. The activity of GPx decreased 55% with ardisin (P<0.05) and 51% with EGCG (P<0.05), and MDA decreased 7% and 23% (P<0.05) with the same treatments. The concentration of GSH also improved when the cells were incubated with either EGCG (49%, P<0.05) or ardisin (83%, P<0.05) simultaneously with 1-NP, relative to 1-NP alone. Moreover, ardisin decreased MDA formation by 65% (p<0.05), and enhanced the activity of GR by 137% (P<0.05). These results suggest that ardisin is a better suppressor of lipid peroxidation induced by benomyl and 1-NP than EGCG. It is concluded that ardisin and EGCG are potent antioxidants that can afford protection against free radical mediated diseases.
Assuntos
Antioxidantes/farmacologia , Benomilo/toxicidade , Catequina/análogos & derivados , Catequina/farmacologia , Fungicidas Industriais/toxicidade , Hepatócitos/efeitos dos fármacos , Pirenos/toxicidade , Resorcinóis/farmacologia , Animais , Benomilo/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Meios de Cultura , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Masculino , Malondialdeído/metabolismo , Proteínas/metabolismo , Ratos , Ratos WistarRESUMO
Herbal tea preparations of Ardisia compressa (AC) have been used in folk medicine against liver disorders. The objective of this study was to evaluate the in vitro protective effect of an aqueous extract of dry leaves of AC on 1-nitropyrene (1-NP) induced cytotoxicity on rat hepatocytes. Lipid peroxidation (malondialdehyde), antioxidant enzyme activities (glutathione reductase, glutathione peroxidase, superoxide dismutase) and glutathione levels were studied. After 2 h of incubation, 0.25 microg/ml of 1-NP had an approximately 50% cytotoxic effect on hepatocytes. This environmental toxicant also increased malondialdehyde (77%), and glutathione peroxidase (46%), producing a significant consumption of endogenous antioxidant glutathione. (-)Epigallocatechin 3-gallato (EGCG) and AC decreased the viability of hepatocytes after 2 h of incubation at concentrations above 3 microg/ml and 2.52 microg, equivalents of (+)catechin/ml, respectively. A 100% hepatocyte protection was observed when cells were first exposed to AC (2.52 microg, equivalents of (+)catechin/ml), and then followed by 1-NP (0.25 microg/ml). Cells incubated with AC, either simultaneously or before treatment with 1-NP, were protected 75 and 84%, respectively. Cell protection of AC was superior to EGCG. Addition of AC to 1-NP (1:10) modulated superoxide dismutase and glutathione reductase activities (P<0.005), as well as the cellular level of GSH. The results indicate that AC has an antioxidant protective effect on rat hepatocytes when exposed to 1-NP.