RESUMO
Bioassay-guided investigation of the EtOAc-soluble extract of a culture of the marine-derived fungus Peroneutypa sp. M16 led to the isolation of seven new polyketide- and terpenoid-derived metabolites (1, 2, 4-8), along with known polyketides (3, 9-13). Structures of compounds 1, 2, and 4-8 were established by analysis of spectroscopic data. Absolute configurations of compounds 1, 2, 4, 6, 7, and 8 were determined by the comparison of experimental ECD spectra with calculated CD data. Compound 5 exhibited moderate antiplasmodial activity against both chloroquine-sensitive and -resistant strains of Plasmodium falciparum.
Assuntos
Policetídeos , Xylariales , Policetídeos/química , Terpenos/química , Estrutura Molecular , Extratos VegetaisRESUMO
The over-production of reactive oxygen species (ROS) can cause oxidative damage to a large number of molecules, including DNA, and has been associated with the pathogenesis of several disorders, such as diabetes mellitus (DM), dyslipidemia and periodontitis (PD). We hypothesise that the presence of these diseases could proportionally increase the DNA damage. The aim of this study was to assess the micronucleus frequency (MNF), as a biomarker for DNA damage, in individuals with type 2 DM, dyslipidemia and PD. One hundred and fifty patients were divided into five groups based upon diabetic, dyslipidemic and periodontal status (Group 1 - poor controlled DM with dyslipidemia and PD; Group 2 - well-controlled DM with dyslipidemia and PD; Group 3 - without DM with dyslipidemia and PD; Group 4 - without DM, without dyslipidemia and with PD; and Group 5 - without DM, dyslipidemia and PD). Blood analyses were carried out for fasting plasma glucose, HbA1c and lipid profile. Periodontal examinations were performed, and venous blood was collected and processed for micronucleus (MN) assay. The frequency of micronuclei was evaluated by cell culture cytokinesis-block MN assay. The general characteristics of each group were described by the mean and standard deviation and the data were submitted to the Mann-Whitney, Kruskal-Wallis, Multiple Logistic Regression and Spearman tests. The Groups 1, 2 and 3 were similarly dyslipidemic presenting increased levels of total cholesterol, low density lipoprotein cholesterol and triglycerides. Periodontal tissue destruction and local inflammation were significantly more severe in diabetics, particularly in Group 1. Frequency of bi-nucleated cells with MN and MNF, as well as nucleoplasmic bridges, were significantly higher for poor controlled diabetics with dyslipidemia and PD in comparison with those systemically healthy, even after adjusting for age, and considering Bonferroni's correction. Elevated frequency of micronuclei was found in patients affected by type 2 diabetes, dyslipidemia and PD. This result suggests that these three pathologies occurring simultaneously promote an additional role to produce DNA impairment. In addition, the micronuclei assay was useful as a biomarker for DNA damage in individuals with chronic degenerative diseases.
Assuntos
Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/patologia , Dislipidemias/complicações , Dislipidemias/patologia , Micronúcleos com Defeito Cromossômico , Periodontite/complicações , Periodontite/patologia , Adulto , Demografia , Feminino , Humanos , Modelos Logísticos , Masculino , Testes para Micronúcleos , Pessoa de Meia-IdadeRESUMO
The present study describes the antimicrobial activity of five pimarane-type diterpenes obtained by fungal biotransformation against several nosocomial multidrug-resistant bacteria. Among the investigated metabolites, ent-8(14),15-pimaradien-3ß-ol was the most active compound, with very promising minimal inhibitory concentration values (between 8.0 and 25.0 µg mL(-1)). Time-kill assays using this metabolite against Staphylococcus aureus (HCRP180) revealed that this compound exerted its bactericidal effect within 24 h at all the evaluated concentrations (8.0, 16.0, and 24.0 µg mL(-1)). When this metabolite was associated with vancomycin at their minimal bactericidal concentration values, the resulting combination was able to drastically reduce the number of viable strains of S. aureus within the first 6 h, compared with these chemicals alone. The checkerboard assays conducted against this microorganism did not evidence any synergistic effects when this same combination was employed. In conclusion, our results point out that ent-8(14),15-pimaradien-3ß-ol is an important metabolite in the search for new effective antimicrobial agents.
Assuntos
Abietanos/farmacologia , Antibacterianos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Abietanos/química , Abietanos/isolamento & purificação , Antibacterianos/química , Antibacterianos/isolamento & purificação , Aspergillus ochraceus/metabolismo , Asteraceae/química , Biotransformação , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana , Raízes de Plantas/química , Vancomicina/farmacologiaRESUMO
We evaluated the antibacterial activity of three diterpenes isolated from natural sources against a panel of microorganisms responsible for bovine mastitis. ent-Copalic acid (CA) was the most active metabolite, with promising MIC values (from 1.56 to 6.25 µg mL-1) against Staphylococcus aureus (ATCC and clinical isolate), Staphylococcus epidermidis, Streptococcus agalactiae, and Streptococcus dysgalactiae. We conducted time-kill assays of CA against S. aureus, a commensal organism considered to be a ubiquitous etiological agent of bovine mastitis in dairy farms worldwide. In the first 12 h, CA only inhibited the growth of the inoculums (bacteriostatic effect), but its bactericidal effect was clearly noted thereafter (between 12 and 24 h). In conclusion, CA should be considered for the control of several Gram-positive bacteria related to bovine mastitis.
Assuntos
Diterpenos/farmacologia , Mastite Bovina/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Bovinos , Diterpenos/química , Feminino , Mastite Bovina/microbiologia , Mikania/química , Extratos Vegetais/farmacologia , Staphylococcus aureus/patogenicidadeRESUMO
The carbon isotopic composition of individual plant leaf waxes (a proxy for C(3) vs. C(4) vegetation) in a marine sediment core collected from beneath the plume of Sahara-derived dust in northwest Africa reveals three periods during the past 192,000 years when the central Sahara/Sahel contained C(3) plants (likely trees), indicating substantially wetter conditions than at present. Our data suggest that variability in the strength of Atlantic meridional overturning circulation (AMOC) is a main control on vegetation distribution in central North Africa, and we note expansions of C(3) vegetation during the African Humid Period (early Holocene) and within Marine Isotope Stage (MIS) 3 ( approximately 50-45 ka) and MIS 5 ( approximately 120-110 ka). The wet periods within MIS 3 and 5 coincide with major human migration events out of sub-Saharan Africa. Our results thus suggest that changes in AMOC influenced North African climate and, at times, contributed to amenable conditions in the central Sahara/Sahel, allowing humans to cross this otherwise inhospitable region.
Assuntos
Clima , Emigração e Imigração/história , África do Norte , Isótopos de Carbono/análise , Sedimentos Geológicos/análise , História Antiga , Humanos , Folhas de Planta/química , Ceras/químicaRESUMO
The schistosomicidal effects of pimaradienoic acid (PA) and two derivatives, obtained by fungal transformation in the presence of Aspergillus ochraceus, were investigated. PA was the only compound with antischistosomal activity among the three diterpenes studied, with the ability to significantly reduce the viability of the parasites at concentrations ranging from 25 to 100 µM. PA also promoted morphological alterations of the tegument of Schistosoma mansoni, separated all the worm couples, and affected the production and development of eggs. Moreover, this compound was devoid of toxicity toward human fibroblasts. In a preliminary in vivo experiment, PA at a dose of 100 mg/kg significantly diminished the number of parasites in infected Balb/c mice. Taken together, these results show that PA may be potentially employed in the discovery of novel schistosomicidal agents, and that diterpenes are an important class of natural compounds for the investigation of agents capable of fighting the parasite responsible for human schistosomiasis.
Assuntos
Aspergillus ochraceus/metabolismo , Diterpenos/metabolismo , Diterpenos/uso terapêutico , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/tratamento farmacológico , Esquistossomicidas/metabolismo , Esquistossomicidas/uso terapêutico , Animais , Asteraceae/química , Biotransformação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Diterpenos/química , Diterpenos/farmacologia , Fibroblastos/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Schistosoma mansoni/crescimento & desenvolvimento , Esquistossomose mansoni/parasitologia , Esquistossomicidas/química , Esquistossomicidas/farmacologiaRESUMO
Sedimentary organic pollution in the urban reaches of the Thames estuary is changing from fossil fuel hydrocarbons to emerging synthetic chemicals. De-industrialisation of London was assessed in three cores from Chiswick (Ait/Eyot) mud island using pharmaceuticals, faecal sterols, hydrocarbons (TPH, PAH), Black Carbon (BC) and organotins (TBT). These ranked in the order; BC 7590-30219 mg/kg, mean 16,000 mg/kg > TPH 770-4301, mean 1316 mg/kg > Σ16PAH 6.93-107.64, mean 36.46 mg/kg > coprostanol 0.0091-0.42 mg/kg, mean of 0.146 mg/kg > pharmaceuticals 2.4-84.8 µg/kg, mean 25 µg/kg. Hydrocarbons co-varied down-profile revealing rise (1940s), peak (1950s -1960s) and fall (1980s) and an overall 3 to 25-fold decrease. In contrast, antibiotics, anti-inflammatory (ibuprofen, paracetamol) and hormone (17ß-estradiol) increased 3 to 50-fold toward surface paralleling increasing use (1970s-2018). The anti-epileptics, carbamazepine and epoxcarbamazepine showed appreciable down-core mobility. Faecal sterols confirmed non-systematic incorporation of treated sewage. Comparison to UK sediment quality guidelines indicate exceedance of AL2 for PAH whereas TBT was below AL1.
Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Londres , Poluentes Orgânicos Persistentes , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios , Esgotos/análise , Poluentes Químicos da Água/análiseRESUMO
The antimicrobial activity of four labdane-type diterpenes isolated from the oleoresin of Copaifera langsdorffii as well as of two commercially available diterpenes (sclareol and manool) was investigated against a representative panel of microorganisms responsible for periodontitis. Among all the evaluated compounds, (-)-copalic acid (CA) was the most active, displaying a very promising MIC value (3.1 µg mL-1; 10.2 µM) against the key pathogen (Porphyromonas gingivalis) involved in this infectious disease. Moreover, CA did not exhibit cytotoxicity when tested in human fibroblasts. Time-kill curve assays performed with CA against P. gingivalis revealed that this compound only inhibited the growth of the inoculums in the first 12 h (bacteriostatic effect). However, its bactericidal effect was clearly noted thereafter (between 12 and 24 h). It was also possible to verify an additive effect when CA and chlorhexidine dihydrochloride (CHD, positive control) were associated at their MBC values. The time curve profile resulting from this combination showed that this association needed only six hours for the bactericidal effect to be noted. In summary, CA has shown to be an important metabolite for the control of periodontal diseases. Moreover, the use of standardized extracts based on copaiba oleoresin with high CA contents can be an important strategy in the development of novel oral care products.
Assuntos
Anti-Infecciosos/farmacologia , Diterpenos/farmacologia , Fabaceae/química , Periodontite/microbiologia , Extratos Vegetais/química , Porphyromonas gingivalis/efeitos dos fármacos , Anti-Infecciosos/química , Diterpenos/química , Humanos , Testes de Sensibilidade Microbiana , Estrutura MolecularRESUMO
Casearia sylvestris is used in Brazil as a popular medicine to treat ulcer, inflammation and tumour. Caseargrewiin F is a clerodane diterpene isolated from the ethanolic leaf extract of C.sylvestris. The aim of the study was to assess the capacity of the ethanolic extract of C.sylvestris leaves and caseargrewiin F to protect DNA and verify if both the compounds cause some DNA damage, using the micronucleus (MN) test and comet assay in mice. Balb-C mice were treated with the extract [3.13, 6.25, 12.5, 25, 50 and 75 mg/kg body weight (b.w.)] and caseargrewiin F (0.16, 0.32, 0.63, 1.3, 2.5 and 3.8 mg/kg b.w.) for 14 days. On day 15, DNA damage was induced by intra-peritoneal (i.p.) injection of cyclophosphamide (CP) (i.p.) at 50 mg/kg b.w. after the MN test and comet assay were performed. A protective effect of ethanolic extract was observed in MN test (6.25 and 12.5 mg/kg b.w.) and the comet assay (3.13 and 6.25, 12.5 and 25 mg/kg b.w.). Caseargrewiin F showed protective effect at 0.63, 1.3 and 2.5 mg/kg b.w. only in comet assay. We also tested the ability of compounds of C.sylvestris to induce MN and to increase the comet assay tail moment. The experimental design was similar to the DNA protection assay except that in test groups we omitted the CP challenge. We observed increased damage at 50 and 75 mg/kg b.w. of ethanolic extract of C.sylvestris and caseargrewiin F at 3.18 mg/kg b.w. in both the MN test and comet assay. We conclude that ethanolic extract of C. sylvestris and caseargrewiin F can protect cells against DNA damage induced by CP at low concentrations, but at high concentrations these compounds also induce DNA damage.
Assuntos
Casearia/metabolismo , Dano ao DNA , Diterpenos/farmacologia , Etanol/química , Extratos Vegetais/farmacologia , Animais , Peso Corporal , Cromatografia Líquida de Alta Pressão , Ensaio Cometa , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes para Micronúcleos , Modelos Químicos , Folhas de Planta/metabolismoRESUMO
Inflammatory diseases, as periodontal disease (PD), has been associated with disturbance of lipid and glycemic metabolisms, as demonstrated by the increasing of PD patients with type 2 diabetes mellitus (T2D) and/or dyslipidemia comorbidities. We aimed to investigate the expression of inflammation and lipid metabolism genes, and correlations among clinical and biochemical characteristics in normoglycemic or T2D patients with dyslipidemia and PD, in comparison with healthy individuals. Five groups of 30 individuals each (150 patients) were formed based upon T2D, dyslipidemic and periodontal status. Blood analyses of lipid and glycemic profiles were carried out, and the gene expression was assessed by RT-qPCR. The systemic expression of IL6, TNFA and LEP genes were significantly higher in T2D, dyslipidemia and PD patients, while the PECAM1 gene showed the opposite. Higher RETN levels were found in patients with T2D independently of their glycemic control status. There were positive correlations between: TNFA, LEP and RETN with worse periodontal parameters; IL6, TNFA, ADIPOR1, LEP and RETN with waist-to-hip ratio; glycemic parameters with RETN; total cholesterol and triglycerides with LEP expression. We conclude that pro-inflammatory cytokines were related with worse lipid, glycemic and periodontal parameters, reinforcing that a hyper-inflammatory status connects systemic and oral inflammatory diseases.
Assuntos
Biomarcadores/análise , Periodontite Crônica/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Dislipidemias/fisiopatologia , Inflamação/genética , Metabolismo dos Lipídeos/genética , Adulto , Glicemia/análise , Brasil/epidemiologia , Estudos de Casos e Controles , Citocinas/sangue , Feminino , Seguimentos , Humanos , Incidência , Inflamação/epidemiologia , Inflamação/patologia , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Prognóstico , Triglicerídeos/sangueRESUMO
In this study, ent-kaurenoic acid derivatives were obtained by microbial transformation methodologies and tested against breast cancer cell lines (MCF-7). A multivariate quantitative-structure activity relationship (QSAR) analysis was performed taking into account both microbial transformation derivatives and other analogues previously reported in literature to give some insight into the main features behind the cytotoxic activity displayed by kaurane-type diterpenes against MCF-7â¯cells. The partial least square regression (PLS) method was employed in the training set and the best PLS model was built with a factor describing 69.92% of variance and three descriptors (logP, εHOMO and εHOMO-1) selected by the Ordered Predictors Selection (OPS) algorithm. The QSAR model provided reasonable regression (Q2â¯=â¯0.64, R2â¯=â¯0.72, SECâ¯=â¯0.29 and SEVâ¯=â¯0.33). The model was validated by leave-N-out cross-validation, y-randomization and external validation (R2predâ¯=â¯0.89 and SEPâ¯=â¯0.27). The selected descriptors indicated that the activity was mainly related to electronic parameters (HOMO and HOMO-1 molecular orbital energies), as well as to logP. These findings suggest that higher activity values are directly related with both higher logP and frontier orbital energy values. The positive relationship between these orbitals and the activity suggests that the ent-kaurenoic acid analogues interaction with the target involves charge displacement, which is entirely consistent with the literature. Based on these findings, three compounds were proposed and one of them was synthesized and tested. The experimental result confirmed the activity predicted by the model.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Diterpenos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Diterpenos/química , Diterpenos/isolamento & purificação , Ensaios de Seleção de Medicamentos Antitumorais , Fabaceae/química , Feminino , Humanos , Células MCF-7 , Relação Quantitativa Estrutura-Atividade , Teoria QuânticaRESUMO
In the screening for biological active compounds, the biotransformation processes catalyzed by filamentous fungi are useful because they can provide information about the possible appearance of toxic metabolites after oral administration and also generate new leads. In this paper, biotransformation of lapachol (1) by three fungal strains, Mucor circinelloides NRRL3631, Botrytis cinerea UCA992 and Botrytis cinerea 2100, has been investigated for the first time. Lapachol (1) was biotransformed into avicequinone-A (2) by M circinelloides, 3'-hydroxylapachol (3) by B. cinerea, and into dehydro-α-lapachone (4) by both fungi. All these compounds were evaluated for their cytotoxic activities. The metabolite 2 displayed non-selective cytotoxicity against tumor and normal cell lines, 3 did not show cytotoxicity against the same cells, while 4 showed higher cytotoxicity against cancer cell lines than lapachol (1). The transformation of 1 into harmless and reactive metabolites evidences the importance of the evaluation of drug metabolism in the drug discovery process. Antifungal potential of lapachol (1) and its metabolites 2 and 4 against B. cinerea has also been evaluated. Dehydro-α-lapachone (4) has been shown to be less toxic to fungal growth than lapachol (1), which indicates a detoxification mechanism of the phytopathogen.
Assuntos
Antifúngicos/farmacologia , Antineoplásicos/farmacologia , Fungos/metabolismo , Naftoquinonas/química , Naftoquinonas/metabolismo , Antifúngicos/química , Antifúngicos/metabolismo , Antineoplásicos/química , Antineoplásicos/metabolismo , Biotransformação , Botrytis , Linhagem Celular , Fungos/efeitos dos fármacos , Humanos , Estrutura MolecularRESUMO
BACKGROUND: Pesticides are of concern in Bolivia because of increasing use. Frequent intoxications have been demonstrated due to use of very toxic pesticides, insufficient control of distribution and sale and little knowledge among farmers of protective measures and hygienic procedures. METHOD: Questionnaires were applied and blood tests taken from 81 volunteers from La Paz County, of whom 48 were pesticide exposed farmers and 33 non-exposed controls. Sixty males and 21 females participated with a mean age of 37.3 years (range 17-76). Data of exposure and possible genetic damage were collected and evaluated by well known statistical methods, controlling for relevant confounders. To measure genetic damage chromosomal aberrations and the comet assay analysis were performed. RESULTS: Pesticide exposed farmers had a higher degree of genetic damage compared to the control group. The number of chromosomal aberrations increased with the intensity of pesticide exposure. Females had a lower number of chromosomal aberrations than males, and people living at altitudes above 2500 metres seemed to exhibit more DNA damage measured by the comet assay. CONCLUSIONS: Bolivian farmers showed signs of genotoxic damage, probably related to exposure to pesticides. Due to the potentially negative long term health effects of genetic damage on reproduction and the development of cancer, preventive measures are recommended. Effective control with imports and sales, banning of the most toxic pesticides, education and information are possible measures, which could help preventing the negative effects of pesticides on human health and the environment.