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1.
Fitoterapia ; 173: 105810, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38163448

RESUMO

Ent-hardwickiic acid is the major compound of Copaifera pubiflora Benth oleoresin traditionally used in Brazilian folk medicine as an antimicrobial agent. Microbial transformation of ent-hardwickiic by Cunninghamella elegans ATCC 10028b resulted in two and five antifungal derivatives (four new ones) produced in the Czapek modified and Koch's K1 media, respectively. The derivatives were isolated and their structures were determined by spectral analysis, namely 1D/2D NMR and HR-ESIMS. All compounds were tested for cytotoxic and antifungal activities and they were not cytotoxic to the tested cell lines, but all derivatives showed fungicidal activity against Candida glabrata and Candida krusei, which have emerged as resistant to fluconazole. One of the yet unreported biotransformation products displayed the strongest activity with minimum fungicidal concentration values smaller than the other compounds, including fluconazole.


Assuntos
Antifúngicos , Diterpenos , Fluconazol , Fluconazol/farmacologia , Candida , Estrutura Molecular , Testes de Sensibilidade Microbiana
2.
J Nat Prod ; 86(6): 1476-1486, 2023 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-37289832

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 Vegetais
3.
Chem Biodivers ; 19(3): e202100757, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35092349

RESUMO

Candida species are responsible for causing invasive candidiasis with high mortality rate and their resistance to available antifungal drugs is a major clinical challenge. Biotransformation process of the labdane diterpene ent-labd-8(17)-en-15,18-dioic acid (1) carried out with Cunninghamella elegans afforded five new derivatives (compounds 2-6). Unusual regioselective hydroxylation of the methyl group at the C-20 position of labdane-type diterpene was achieved and all compounds were subjected to cytotoxicity and antifungal evaluations. Compound 1 and its derivatives were not cytotoxic to normal (MCF-10A) and tumor (MCF-7) cell lines. Compounds 2 and 3 exhibited fungistatic activity against all tested Candida strains at lower concentrations than fluconazole. Both compounds also showed the strongest fungicidal activity against C. albicans, which is the most prevalent fungal agent involved in candidemia.


Assuntos
Candida , Diterpenos , Antifúngicos/farmacologia , Biotransformação , Candida/metabolismo , Cunninghamella , Diterpenos/metabolismo , Diterpenos/farmacologia , Fluconazol , Testes de Sensibilidade Microbiana
4.
Diabetes Metab Syndr ; 13(4): 2715-2722, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31405698

RESUMO

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/sangue
5.
Phytochemistry ; 156: 214-223, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30321792

RESUMO

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-7 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 (Q2 = 0.64, R2 = 0.72, SEC = 0.29 and SEV = 0.33). The model was validated by leave-N-out cross-validation, y-randomization and external validation (R2pred = 0.89 and SEP = 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 Quântica
6.
J. Bras. Patol. Med. Lab. (Online) ; 53(6): 362-367, Nov.-Dec. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-893580

RESUMO

ABSTRACT Introduction: Beta-thalassemia is caused by a deficient synthesis of the ß-chain of hemoglobin, which leads to a chronic, microcytic and hypochromic anemia. More than 200 mutations have already been associated with this type of thalassemia, and their frequencies may vary according to the population. Objectives: The objectives of this study were to determine the frequencies of CD39, IVS1-1, IVS1-6 and IVS1-110 mutations in people with beta-thalassemia from the city of Franca, São Paulo, and to evaluate the influence of the genotypes on hematological alterations. Methods: Venous blood samples were collected from 25 volunteers previously diagnosed with beta-thalassemia. Complete blood counts (CBC) were performed, and the identification of the mutations was carried out using the polymerase chain reaction (PCR). Results: The CD39 mutation was found in 11 (44%) individuals, followed by IVS1-6 (9; 36%) and IVS1-110 (4; 16%). One patient (4%) did not present any of these mutations. IVS1-6 mutation was inversely correlated to red cell distribution width (RDW) (rs = -0.44; p = 0.034), and CD39 was correlated to lower mean corpuscular volume (MCV) (rs = -0.44; p = 0.034). Multivariable linear regression models showed that the CD39 mutation carriers have lower levels for hemoglobin (ß = -0.61; p = 0.044) and hematocrit (ß = -2.1; p = 0.018). Conclusion: The results showed a high frequency of the CD39 mutation in the city of Franca, and the correlations observed between the presence of CD39 mutation and the hematological alterations suggest a genotype influence on the phenotype of beta-thalassemia, which would contribute to the clinical variations of this hemoglobinopathy.


RESUMO Introdução: A betatalassemia é causada pela síntese deficiente da cadeia ß da hemoglobina, o que leva à ocorrência das anemias crônica, microcítica e hipocrômica. Mais de 200 mutações já foram associadas a esse tipo de talassemia, mesmo que diferentes populações apresentem frequências variadas para cada uma delas. Objetivos: Os objetivos deste estudo foram determinar as frequências das mutações CD39, IVS1-1, IVS1-6 e IVS1-110 em indivíduos betatalassêmicos da cidade de Franca, São Paulo, e avaliar a influência dos genótipos sobre alterações hematológicas. Métodos: Amostras de sangue venoso foram coletadas de 25 voluntários previamente diagnosticados com betatalassemia. Foram realizados hemogramas completos, e a identificação das mutações foi feita utilizando a técnica de reação em cadeia da polimerase (PCR). Resultados: A mutação CD39 foi encontrada em 44% dos indivíduos, seguida por IVS1-6 (36%) e IVS1-110 (16%). Um paciente (4%) não apresentou nenhuma das mutações. A mutação IVS1-6 correlacionou-se inversamente ao red cell distribution width (RDW) (rs = -0,44; p = 0,034), enquanto a presença da mutação CD39 mostrou-se correlacionada a menores valores de volume corpuscular médio (VCM) (rs = -0,44; p = 0,034). Modelos de regressão linear multivariados mostraram que os portadores da mutação CD39 possuem menores valores de hemoglobina (ß = -0,61; p = 0,044) e hematócrito (ß = -2,1; p = 0,018). Conclusão: Os resultados mostraram alta frequência da mutação CD39 na cidade de Franca, e as correlações observadas entre a presença da mutação CD39 e as alterações hematológicas sugerem influência do genótipo sobre o fenótipo da betatalassemia, o que poderia contribuir para as variações clínicas dessa hemoglobinopatia.

7.
J Nat Prod ; 79(6): 1668-78, 2016 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-27227682

RESUMO

Application of a refined procedure of experimental design and chemometric analysis to improve the production of curvularin-related polyketides by a marine-derived Penicillium sp. DRF2 resulted in the isolation and identification of cyclothiocurvularins 6-8 and cyclosulfoxicurvularins 10 and 11, novel curvularins condensed with a mercaptolactate residue. Two additional new curvularins, 3 and 4, are also reported. The structures of the sulfur-bearing curvularins were unambiguously established by analysis of spectroscopic data and by X-ray diffraction analysis. Analysis of stable isotope feeding experiments with [U-(13)C3(15)N]-l-cysteine confirmed the presence of the 2-hydroxy-3-mercaptopropanoic acid residue in 6-8 and the oxidized sulfoxide in 10 and 11. Cyclothiocurvularins A (6) and B (7) are formed by spontaneous reaction between 10,11-dehydrocurvularin (2) and mercaptopyruvate (12) obtained by transamination of cysteine. High ratios of [U-(13)C3(15)N]-l-cysteine incorporation into cyclothiocurvularin B (7), the isolation of two diastereomers of cyclothiocurvularins, the lack of cytotoxicity of cyclothiocurvularin B (7) and its methyl ester (8), and the spontaneous formation of cyclothiocurvularins from 10,11-dehydrocurvularin and mercaptopyruvate provide evidence that the formation of cyclothiocurvularins may well correspond to a 10,11-dehydrocurvularin detoxification process by Penicillium sp. DRF2.


Assuntos
Penicillium/química , Policetídeos/isolamento & purificação , Cristalografia por Raios X , Cisteína , Ensaios de Seleção de Medicamentos Antitumorais , Biologia Marinha , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Policetídeos/química , Policetídeos/farmacologia , Estereoisomerismo , Zearalenona/análogos & derivados , Zearalenona/química
8.
Molecules ; 20(10): 18264-78, 2015 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-26457701

RESUMO

We report herein the synthesis of six diterpene derivatives, three of which are new, generated through known organic chemistry reactions that allowed structural modification of the existing natural products kaurenoic acid (1) and copalic acid (2). The new compounds were fully characterized using high resolution mass spectrometry, infrared spectroscopy, ¹H- and (13)C-NMR experiments. We also report the evaluation of the anti-tuberculosis potential for all compounds, which showed some promising results for Micobacterium tuberculosis inhibition. Moreover, the toxicity for each of the most active compounds was also assessed.


Assuntos
Diterpenos/síntese química , Diterpenos/farmacologia , Antituberculosos/síntese química , Antituberculosos/química , Antituberculosos/farmacologia , Produtos Biológicos , Diterpenos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/efeitos dos fármacos , Relação Estrutura-Atividade
9.
J Nat Prod ; 78(5): 1101-12, 2015 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-25924111

RESUMO

HPLC-UV-ELSD-MS-guided fractionation of the anti-parasitic extract obtained from the marine sponge Monanchora arbuscula, collected off the southeastern coast of Brazil, led to the isolation of a series of guanidine and pyrimidine alkaloids. The pyrimidines monalidine A (1) and arbusculidine A (7), as well as the guanidine alkaloids batzellamide A (8) and hemibatzelladines 9-11, represent new minor constituents that were identified by analysis of spectroscopic data. The total synthesis of monalidine A confirmed its structure. Arbusculidine A (7), related to the ptilocaulin/mirabilin/netamine family of tricyclic guanidine alkaloids, is the first in this family to possess a benzene ring. Batzellamide A (8) and hemibatzelladines 9-11 represent new carbon skeletons that are related to the batzelladines. Evaluation of the anti-parasitic activity of the major known metabolites, batzelladines D (12), F (13), L (14), and nor-L (15), as well as of synthetic monalidine A (1), against Trypanosoma cruzi and Leishmania infantum is also reported, along with a detailed investigation of parasite cell-death pathways promoted by batzelladine L (14) and norbatzelladine L (15).


Assuntos
Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Guanidinas/isolamento & purificação , Guanidinas/farmacologia , Poríferos/química , Pirimidinas/isolamento & purificação , Pirimidinas/farmacologia , Alcaloides/química , Animais , Brasil , Guanidinas/química , Leishmania infantum/efeitos dos fármacos , Biologia Marinha , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Testes de Sensibilidade Parasitária , Pirimidinas/química , Trypanosoma cruzi/efeitos dos fármacos
10.
Rev. bras. farmacogn ; 23(6): 877-884, Nov-Dec/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-704265

RESUMO

This paper reports on the chemical composition, the in vitro antischistosomal effects, and the cytotoxicity of the essential oil from the leaves of Lavandula angustifolia Mill., Lamiaceae, grown in the Southeastern Brazil. Borneol (22.4%), epi-α-muurolol (13.4%), α-bisabolol (13.1%), precocene I (13.0%), and eucalyptol (7.9%) were the major essential oil constituents. Incubation with essential oil at 200 μg/ml killed all the adult S. mansoni worms after 24 h (LC50 117.7 and 103.9 μg/ml at 24 and 120 h of incubation, respectively). At a concentration of 50 μg/ ml, the essential oil significantly decreased the motor activity and reduced the percentage of egg development after 120 h. In addition, the essential oil separated all the coupled S. mansoni worm pairs into individual male and female at 25 and 50 μg/ml within 120 and 24 h, respectively. This oil was cytotoxic to GM07492-A cells at only concentrations higher than 200 µg/ml (IC50 243.7 µg/ml). These data indicate that LA-EO exhibits moderate in vitro activity against adult S. mansoni and exerts remarkable effects on eggs development.

11.
Rev. bras. farmacogn ; 23(6): 870-876, Nov-Dec/2013. tab, graf
Artigo em Inglês | LILACS | ID: lil-704267

RESUMO

In this paper we screened the dichloromethane extract from the aerial parts of Salvia officinalis L., Lamiaceae, against a representative panel of microorganisms that cause caries, conducted a bioassay-guided fractionation to establish themselves the most active metabolite (manool) and determined the Salvia officinalis fraction with the manool highest concentration to be used to activate an ingredient in oral care products such as toothpastes and mouthwashes. Both manool and S. officinalis extract showed very promising minimal inhibitory concentration values (between 6.24 and 31.36 µg.ml-1) and time kill curves against the primary causative agents of dental caries (Streptococcus mutans) revealed that, at twice its minimal bactericidal concentration (12.48 µg.ml-1), manool required 6 h to completely kill the bacteria. Salvia officinalis extract at twice its minimal bactericidal concentration (31.36 µg.ml-1 ) needed 12 h. The results achieved with Salvia officinalis extract motivated us to develop and validate an analytical RP-HPLC method to detect and determine manool in this extract. The validation parameters were satisfactorily met and evaluated allows us to consider the developed method suitable for use in different labs. In conclusion, our results evidenced that the manool-rich S. officinalis extract can be considered an analytically validated alternative to develop novel and effective antimicrobial agents against the main bacteria responsible for dental caries.

12.
Molecules ; 18(7): 7865-72, 2013 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-23884123

RESUMO

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/patogenicidade
13.
J Med Food ; 16(2): 180-3, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23289788

RESUMO

The mushroom Agaricus brasiliensis (sun mushroom), native from the southeast of Brazil, is well known by its medicinal properties that include effects on diabetes, cholesterol levels, and osteoporosis. The antimutagenic effects of A. brasiliensis has been investigated recently and revealed some controversial results depending on the temperature by which the A. brasiliensis tea is obtained. In the present study, we evaluated the effect of the A. brasiliensis extract prepared in two different temperatures, 4°C and 25°C, on the doxorubicin-induced DNA strand breaks and chromosomal aberrations (CAs) in human lymphocytes. The results demonstrated that A. brasiliensis was able to reduce the DXR-induced DNA damage in both temperatures; however, the CA test was more sensitive to demonstrate a better reduction when the cells were treated with an extract obtained at 25°C. A. brasiliensis extract obtained in different temperatures exhibited antigenotoxic and anticlastogenic effects in human lymphocytes.


Assuntos
Agaricus/química , Antimutagênicos/farmacologia , Linfócitos/efeitos dos fármacos , Células Cultivadas , Aberrações Cromossômicas/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos
14.
Phytother Res ; 27(10): 1502-7, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23193079

RESUMO

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/farmacologia
15.
Chem Biodivers ; 9(8): 1465-74, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22899607

RESUMO

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/farmacologia
16.
Genet Mol Biol ; 35(2): 498-502, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22888300

RESUMO

Tabebuia sp. is native to tropical rain forests throughout Central and South America. Although the biological and pharmacological effects of bark extracts have been intensely studied, little is known on the extract obtained from the flower. Herein, the genotoxic potential of a flower extract from T. impetiginosa ("ipê roxo") on the blood and liver cells of Wistar rats was evaluated. Experimental procedures involved only male animals. Graduated concentrations of the extract, viz., 100, 300 and 500 mg kg(-1) of body weight, were gavage-administered and 24 h latter cells were collected and processed for analysis. With the exception of the 100 mg kg(-1) dose, a significant increase in DNA damage was noted, when compared with a negative control group. Although the genotoxic potential of this extract was higher in liver cells, the response in both tissues was related to dose-dependency. Even though DNA damage can be corrected before conversion into mutations, further study is recommended to arrive at a better understanding of incurred biological effects.

17.
Molecules ; 16(11): 9611-9, 2011 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-22101836

RESUMO

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 Molecular
18.
Clin Exp Med ; 10(2): 87-92, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19902326

RESUMO

Breast cancer is the second most frequent type of cancer worldwide and is the most common malignant disease among women. Risk factors for breast cancer include early menarche, late menopause, hormonal therapies, exposure to environmental pollutants, smoking and alcohol use. However, increased or prolonged exposure to estrogen is the most important risk factor. It has been suggested that accumulation of DNA damage may contribute to breast carcinogenesis. Epidemiological studies suggest that cytogenetic biomarkers such as micronuclei in peripheral blood lymphocytes may predict cancer risk because they indicate genomic instability in target tissues. The objective of the present study was to evaluate the frequencies of micronuclei and the extent of DNA damage detected by comet assay in peripheral blood lymphocytes of untreated breast cancer patients and healthy women. The study was conducted using peripheral blood lymphocytes from 45 women diagnosed for Ductal "in situ" or invasive breast carcinoma and 85 healthy control women. Micronuclei and comet assays were performed to detect spontaneous DNA damage. The results showed that micronuclei frequencies and tail intensity, detected by comet assay, were significantly higher in the breast cancer group than in controls. The levels of DNA damage were similar in smokers and non-smokers, and aging did not influence the frequencies of micronuclei or tail intensity values observed in either group. In conclusion, the present work demonstrates higher levels of DNA damage in untreated breast cancer patients than in healthy women.


Assuntos
Neoplasias da Mama/patologia , Dano ao DNA , Adulto , Biomarcadores , Ensaio Cometa , Feminino , Humanos , Linfócitos/patologia , Testes para Micronúcleos , Pessoa de Meia-Idade
19.
Genet Mol Biol ; 33(4): 637-40, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21637570

RESUMO

Breast cancer (BC) is the most prevalent type worldwide, besides being one of the most common causes of death among women. It has been suggested that sporadic BC is most likely caused by low-penetrance genes, including those involved in DNA repair mechanisms. Furthermore, the accumulation of DNA damage may contribute to breast carcinogenesis. In the present study, the relationship between two DNA repair genes, viz., XRCC1 (Arg399Gln) and XRCC3 (Thr241Met) polymorphisms, and the levels of chromosome damage detected in 65 untreated BC women and 85 healthy controls, was investigated. Chromosome damage was evaluated through micronucleus assaying, and genotypes determined by PCR-RFLP methodology. The results showed no alteration in the risk of BC and DNA damage brought about by either XRCC1 (Arg399Gln) or XRCC3 (Thr241Met) action in either of the two groups. Nevertheless, on evaluating BC risk in women presenting levels of chromosome damage above the mean, the XRCC3Thr241Met polymorphism was found to be more frequent in the BC group than in the control, thereby leading to the conclusion that there is a slight association between XRCC3 (241 C/T) genotypes and BC risk in the subgroups with higher levels of chromosome damage.

20.
Genet. mol. biol ; Genet. mol. biol;33(4): 637-640, 2010. tab
Artigo em Inglês | LILACS | ID: lil-571515

RESUMO

Breast cancer (BC) is the most prevalent type worldwide, besides being one of the most common causes of death among women. It has been suggested that sporadic BC is most likely caused by low-penetrance genes, including those involved in DNA repair mechanisms. Furthermore, the accumulation of DNA damage may contribute to breast carcinogenesis. In the present study, the relationship between two DNA repair genes, viz., XRCC1 (Arg399Gln) and XRCC3 (Thr241Met) polymorphisms, and the levels of chromosome damage detected in 65 untreated BC women and 85 healthy controls, was investigated. Chromosome damage was evaluated through micronucleus assaying, and genotypes determined by PCR-RFLP methodology. The results showed no alteration in the risk of BC and DNA damage brought about by either XRCC1 (Arg399Gln) or XRCC3 (Thr241Met) action in either of the two groups. Nevertheless, on evaluating BC risk in women presenting levels of chromosome damage above the mean, the XRCC3 Thr241Met polymorphism was found to be more frequent in the BC group than in the control, thereby leading to the conclusion that there is a slight association between XRCC3 (241 C/T) genotypes and BC risk in the subgroups with higher levels of chromosome damage.


Assuntos
Humanos , Feminino , Neoplasias da Mama , Reparo do DNA , Testes para Micronúcleos , Polimorfismo Genético
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