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1.
Arch Insect Biochem Physiol ; 110(3): e21904, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35419839

RESUMO

The sugarcane borer Diatraea saccharalis (Lepidoptera: Crambidae) is an important sugarcane pest and mechanical injuries caused through the mandibles can allow pathogen infections. The mandibles of D. saccharalis, as well as other insects, are associated with mandibular glands with a possible function in food intake and mouthparts lubrication; however, the chemical composition of the secretion is poorly known and its elucidation is important for the comprehensive understanding of plant-insect interactions. This study characterized some proteins and volatiles in the mandibular glands of D. saccharalis larvae. MALDI-TOF/TOF mass spectrometry allowed the identification of 24 predicted proteins within 10 functional classes, including the transport and metabolism of carbohydrates, lipids, amino acids, and nucleotides; Posttranslational protein modifications; energy conversion; intracellular trafficking; transcription; translation; and cytoskeleton function. Metabolites identified from GC/MS analysis revealed the presence of hydrocarbons classified as alcohols, ether, alkanes, and esters with differences in their relative abundance. Linolenic acid, the most abundant metabolite found in this gland, when conjugated with amino acids, can be an elicitor in the plant-herbivore interaction. The results suggest the occurrence of digestive and defensive biochemical components, which may contribute to understanding of the multifunctional roles of the mandibular gland secretion of D. saccharalis larvae during feeding activity.


Assuntos
Lepidópteros , Mariposas , Saccharum , Aminoácidos , Animais , Larva , Mandíbula
2.
Comput Biol Chem ; 92: 107460, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33621907

RESUMO

Garcinia gardneriana is a medicinal tree species used in Brazil in the treatment of hepatitis and gastritis. This use is attributed to phenolic compounds, mainly 7-epiclusianone, guttiferone-A and fukugetin, which present several proven biological activities. However, to the best of our knowledge, no study on the phytotoxic activity of G. gardneriana extracts has been conducted until now. This research proposed to isolate and quantify by high-performance liquid chromatography (HPLC) the major compounds from G. gardneriana seed extracts in ethyl acetate and to evaluate their phytotoxic activities. The natural products 7-epiclusianone, guttiferone-A and fukugetin were quantified at concentrations varying from 0.46 to 1.13 mg mL-1 and were isolated with yields ranging from 7% to 23% (w/w). The phytotoxic assay indicated that the crude extract showed no action on the dry matter of Sorghum bicolor plants, but the isolated compounds fukugetin and 7-epiclusianone had moderate activity. On the other hand, guttiferone-A displayed a greater herbicide activity than glyphosate, a positive control, even in almost three times lower concentrations, causing severe intoxication in the plants. This work is the first report on this activity by the extract of G. gardneriana and its isolated compounds. Besides that, guttiferone-A showed up as a scaffold for the development of new agrochemicals. Complementing these findings, computational studies suggested that this benzophenone can interact effectively with transferase enzymes type, in special caffeic acid O-methyltransferase from S. bicolor (PDB code: 4PGH), indicating a possible mechanism of action in this plant.


Assuntos
Produtos Biológicos/farmacologia , Garcinia/química , Extratos Vegetais/farmacologia , Sorghum/efeitos dos fármacos , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/metabolismo , Brasil , Cromatografia Líquida de Alta Pressão , Conformação Molecular , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo
3.
Nat Prod Res ; 35(21): 4073-4077, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31983232

RESUMO

The prior study of the extraction path is fundamental to optimize the required time and to define the most suitable solvent to extract and determine an analyte of interest in a complex sample. This study aimed to evaluate four extraction modes; solvent sequence in Soxhlet equipment (SES), and by maceration (SEM), direct extraction with ethanol by maceration (EEM), and in Soxhlet equipment (EES), and determine Garcinia brasiliensis bioactive compounds using a validated high-performance liquid chromatography diode-array detection (HPLC-DAD) method. Fukugetin, fukugetina-7''-O-ß-D-glucoside, norathyriol, guttiferone A, and 7-epiclusianone were identified and quantified with authentic standards. Among all four modes applied to extract the main bioactive. From HPLC profile, it was observed that the highest levels of 7-epiclusianone (344.1 mg/g) and guttiferone A (142.8 mg/g) were found in the N-hexane fraction using SEM mode, whereas the highest levels of fukugetin (44.95 mg/g) and norathyriol (3.95 mg/g dry weight) in the ethyl acetate fraction using SES mode.


Assuntos
Garcinia , Cromatografia Líquida de Alta Pressão , Extratos Vegetais
4.
Comput Biol Chem ; 88: 107359, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32853899

RESUMO

The present work proposed the preparation of triazolic analogues of tyrosol, a biophenol found in olive oil and whose wide range of bioactivities has been the target of many studies. We obtained fifteen novel tyrosol derivatives and the compounds of the series were later evaluated as acetylcholinesterase (AChE) inhibitors. The study of AChE inhibition is important for the development of new drugs and pesticides, and especially the research for managing Alzheimer's disease. The most active compound, namely 7-({1-[2-(4-hydroxyphenyl)ethyl]-1H-1,2,3-triazol-4-yl}methoxy)-4-methyl-2H-chromen-2-one (30), showed IC50 value of 14.66 ±â€¯2.29 µmol L-1. Docking experiments corroborated by kinetic assay are suggestive of a competitive inhibition mechanism. Derivatives interacted with amino acids from the AChE active site associated to the development of Alzheimer's disease. The results indicate that the compounds synthesized have a high potential as prototypes for the development of new acetylcholinesterase inhibitors.


Assuntos
Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Triazóis/farmacologia , Animais , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Electrophorus , Simulação de Acoplamento Molecular , Estrutura Molecular , Triazóis/síntese química , Triazóis/química
5.
Nutr Res ; 56: 90-97, 2018 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-30055778

RESUMO

We investigated if pumpkin and flaxseeds could improve postprandial glycemic, food intake, and appetitive responses. Herein, we hypothesize based on the literature that pumpkin seed has potential to lower postprandial glycemic effects. Therefore, we conducted a randomized, single-blind, placebo-controlled, crossover design study involving normoglycemic adults (food intake: n = 25; glycemia: n = 15). Three high-carbohydrate mixed meals presenting no seed (control [C]) or 65 g of the tested seeds (pumpkin seed [P] or flaxseed [F]) were consumed in 3 nonconsecutive days. Test meals had similar nutritional composition. Blood glucose was measured by capillary finger blood at 0 (immediately before), 15, 30, 45, 60, 90, and 120 minutes after the ingestion of each meal, and the incremental area under glycemic response curves (iAUC) were calculated. Appetitive responses were assessed, and dietary records were used to evaluate food intake on testing days. Glucose iAUC was significantly lower in P compared with C (reduction of ~35%, P = .025). There was no significant differences in glucose iAUC between F and C (P = .257). Glycemic response at each time point did not differ between C, P, and F (Pgroup × time = .238). Fiber consumption was higher in F (P = .009) than in C, but there were no differences in appetitive responses, energy, or macronutrient consumptions between dietary interventions. Acute consumption of 65 g of pumpkin seed markedly reduced postprandial glycemia. Pumpkin seed has potential as a hypoglycemic food, which now deserves to be confirmed in long-term studies.


Assuntos
Glicemia/metabolismo , Cucurbita , Dieta , Índice Glicêmico , Hiperglicemia/prevenção & controle , Período Pós-Prandial , Sementes , Apetite , Área Sob a Curva , Estudos Cross-Over , Fibras na Dieta/farmacologia , Método Duplo-Cego , Feminino , Linho , Humanos , Hiperglicemia/sangue , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Masculino , Refeições , Valores de Referência , Resposta de Saciedade/efeitos dos fármacos , Método Simples-Cego , Adulto Jovem
6.
Molecules ; 23(8)2018 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-30049981

RESUMO

A series of novel benzophenone derivatives containing a thiazole heterocyclic nucleus were designed by molecular hybridization. Molecular docking studies have demonstrated the inhibitory potential of the designed compounds against cyclooxygenase (COX) isoenzymes. These compounds were synthesized, characterized, and evaluated for their anti-inflammatory properties by the croton oil-induced ear edema assay to examine their effect on both prostaglandin (PG) production and neutrophils recruitment. The thiazole derivatives displayed a potent effect in terms of reducing ear edema. The analysis suggested that the presence of 4-phenyl-2-hydrazinothiazole and the absence of C4'-OCH3 on the benzophenone derivative structure are strongly related to the inhibition of PG production. In addition, the derivatives 2e, 3a and 3c concomitantly inhibit PG production and neutrophil recruitment, which may be a mechanism of action better than of common NSAIDs due to their inability to inhibit the neutrophil recruitment. Thus, these compounds can be considered as potential lead compounds toward the development of new anti-inflammatory drugs with an innovating mechanism of action.


Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Benzofenonas/química , Benzofenonas/farmacologia , Desenho de Fármacos , Edema/patologia , Infiltração de Neutrófilos/efeitos dos fármacos , Animais , Anti-Inflamatórios/síntese química , Benzofenonas/síntese química , Sítios de Ligação , Domínio Catalítico , Ciclo-Oxigenase 1/química , Ciclo-Oxigenase 2/química , Inibidores de Ciclo-Oxigenase/química , Modelos Animais de Doenças , Edema/tratamento farmacológico , Isomerismo , Camundongos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Ligação Proteica , Relação Estrutura-Atividade
7.
Front Microbiol ; 9: 1203, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29928266

RESUMO

Mastitis is an inflammation of the mammary gland that causes major losses in the dairy industry. Streptococcus spp. are among the main agents of this disease. Increased resistance to antibiotics is one of the causes of therapeutic failure. Plants, due to their broad chemodiversity, are an interesting source of new molecules with antibacterial activity. Using these compounds along with traditional antibiotics is a possible method for reversing resistance. The objective of this work was to determine the interactions between the activities of guttiferone-A and 7-epiclusianone, two active substances isolated from the fruits of Garcinia brasiliensis, and traditional antibiotics against Streptococcus spp. isolated from bovine mastitis and known to be resistant to them. First, the MIC for the antibiotics and bioactive compounds was determined, followed by their activities, alone and in combination. Then, their cytotoxicity was measured in bovine mammary epithelial cells. Finally, molecular docking simulations were performed to elucidate molecular details of the interactions between ß-lactamase and the compounds binding to it (clavulanic acid, ampicillin, 7-epiclusianone, and guttiferone-A). The bacterial isolates were resistant to ampicillin and gentamicin. Both antibiotics showed predominantly synergistic antibacterial activities in combination with guttiferone-A or 7-epiclusianone. These two active substances were not cytotoxic at synergistic concentrations and both showed strong binding to ß-lactamase, which may explain the reversal of ampicillin resistance. These substances are promising for the treatment of bovine mastitis.

8.
Theriogenology ; 111: 56-61, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29428845

RESUMO

This study aimed to evaluate the effects of decreasing permanence period of progesterone (P4) inserts from 9 (9d) to 7 (7d) days in timed-AI (TAI) protocol, as well as their reuse on pregnancy per AI (P/AI) during 7d protocol. At the beginning of all protocols, cows received 2 mg of estradiol benzoate (EB) and a vaginal insert containing 1.9 g of P4. In the 7d protocol, the P4 insert was removed, and cows were given 25 mg of prostaglandin F2α, 0.6 mg of estradiol cypionate and 300 IU of eCG 7 days later. In the 9d protocol, the P4 insert was removed, and cows received the same hormones that were administrated in 7d protocol, however, they were applied on the 9th day of the protocol. In the experiment I, 302 suckled Nellore cows were undergone to 7d protocol, and AI was performed 10-14 h later after estrus detection. In the experiment II, 679 suckled Nellore cows were assigned to receive either 7d or 9d protocols. In the experiment III, 999 suckled Nellore cows were assigned to receive either a new P4 insert (CIDR1), or a P4 insert used previously for 7 (CIDR2), 14 (CIDR3), 21 (CIDR4) or 28 (CIDR5) days, and 227 Nellore heifers received a P4 insert used previously for 21 (CIDR4) or 35 (CIDR6) days during the 7d protocol. When 7d protocol was used, 45% of cows exhibited estrus 48 h after P4 removal. Thus, the AI was performed 55 h after P4 removal in experiments II and III when 7d protocol was used. There was no difference in estrus detection rate (72 vs 74%; P = 0.60), ovulation rate (80 vs 88%; P = 0.13) and P/AI (56 vs 54%; P = 0.49) between 7d and 9d protocols, respectively. In the 7d protocol, the P/AI was similar (P = 0.72) using a new P4 insert (47%), or a P4 insert used previously for 7 (48%), 14 (45%), 21 (54%), or 28 (49%) days in Nellore suckled cows. In addition, P/AI was similar (P = 0.15) in heifers that received a P4 insert used previously for 21 (52%), or 35 (61%) days during the 7d protocol. In conclusion, cows submitted to 7d or 9d protocols had similar reproductive performance, and the reuse of P4 inserts up to 6 folds (five in suckled cows plus one in heifers) did not affect reproductive performance of Nellore cattle in 7d protocol.


Assuntos
Bovinos , Progesterona/farmacologia , Animais , Animais Lactentes , Relação Dose-Resposta a Droga , Esquema de Medicação , Sincronização do Estro , Feminino , Lactação , Progesterona/administração & dosagem
9.
J Mol Model ; 23(4): 140, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28361442

RESUMO

The quantum theory of atoms in molecules (QTAIM) and density functional theory (DFT) calculations were employed to investigate the structure and tautomeric equilibrium of epiclusianone, a polyisoprenylated benzophenone with interesting biological activities. Two different exchange-correlation functionals were employed, namely ωB97x-D and M06-2x, including implicit solvent models (benzene and DMSO). Our results for the thermodynamic properties show that the isomer in which the H atom is bonded to the oxygen away from the benzene ring is the most stable tautomer form of the epiclusianone, thus confirming previous charge density analysis from X-ray diffraction data (Martins et al. J Braz Chem Soc 18(8):1515-1523, 22).

10.
Theriogenology ; 86(8): 1939-43, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27474237

RESUMO

The aim of this study was to evaluate the reproductive performance of 411 Nellore cows (198 nulliparous, 80 primiparous, and 133 multiparous) submitted to the 5dCO-Synch + P4 or 7dEB + P4 systems. The 5dCO-Synch + P4 system consisted of insertion of an intravaginal progesterone (P4) insert and 100 µg of GnRH (intramuscularly [i.m.]) on Day 0. On Day 5, the P4 insert was removed, and two doses of 25 mg of PGF2α (i.m.) were administered 6 hours apart. Cows not detected in estrus until 55 hours after insert removal received 100 µg of GnRH i.m. 17 hours later (i.e., 72 hours after P4 removal). The 7dEB + P4 system consisted of insertion of a P4 insert and 2 mg of estradiol benzoate (i.m.) on Day 0. On Day 7, the P4 insert was removed and 25 mg of PGF2α, 0.6 mg of estradiol cypionate, and 300 IU of eCG were administered i.m. In both systems, artificial insemination (AI) was performed according to estrus detection (i.e., cows detected in estrus until 55 hours after insert removal were inseminated at 55 hours and cows detected in estrus later or those not detected in estrus were inseminated at 72 hours). Estrus-detection risk was greater (P < 0.05) in 7dEB + P4 (80.4%) than 5dCO-Synch + P4 system (36.4%). Progesterone concentration 10 days after AI was greater (P < 0.05) in 7dEB + P4 than 5dCO-Synch + P4 system in primiparous and multiparous but did not differ between systems in nulliparous cows. Pregnancy per AI was greater (P < 0.05) in 7dEB + P4 (49.7%) than 5dCO-Synch + P4 (35.4%) system. Primiparous had lower estrus-detection risk (25.0%), ovulation risk (76.6%), and pregnancy per AI (28.7%) than multiparous or nulliparous cows. In conclusion, reproductive performance was reduced with the 5dCO-Synch + P4 in comparison with the 7dEB + P4 system in Nellore cows. Moreover, the reproductive traits observed for primiparous cows indicate that more attention is required when timed AI programs are started early after calving.


Assuntos
Bovinos/fisiologia , Sincronização do Estro/métodos , Inseminação Artificial/veterinária , Ovulação/efeitos dos fármacos , Animais , Dinoprosta/administração & dosagem , Dinoprosta/farmacologia , Estradiol/administração & dosagem , Estradiol/análogos & derivados , Estradiol/farmacologia , Feminino , Hormônio Liberador de Gonadotropina/administração & dosagem , Hormônio Liberador de Gonadotropina/farmacologia , Inseminação Artificial/métodos , Gravidez , Progesterona/administração & dosagem , Progesterona/farmacologia , Fatores de Tempo
11.
Bioorg Med Chem Lett ; 26(5): 1485-9, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26848109

RESUMO

The human tissue kallikreins (KLK1-KLK15) comprise a family of 15 serine peptidases detected in almost every tissue of the human body and that actively participate in many physiological and pathological events. Some kallikreins are involved in diseases for which no effective therapy is available, as for example, epithelial disorders, bacterial infections and in certain cancers metastatic processes. In recent years our group have made efforts to find inhibitors for all kallikreins, based on natural products and synthetic molecules, and all the inhibitors developed by our group presented a competitive mechanism of inhibition. Here we describe fukugetin, a natural product that presents a mixed-type mechanism of inhibition against KLK1 and KLK2. This type of inhibitor is gaining importance today, especially for the development of exosite-type inhibitors, which present potential to selectively inhibit the enzyme activity only against specific substrate.


Assuntos
Biflavonoides/farmacologia , Produtos Biológicos/farmacologia , Inibidores de Serina Proteinase/farmacologia , Calicreínas Teciduais/antagonistas & inibidores , Biflavonoides/química , Biflavonoides/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Relação Dose-Resposta a Droga , Garcinia/química , Humanos , Modelos Moleculares , Conformação Molecular , Inibidores de Serina Proteinase/química , Inibidores de Serina Proteinase/isolamento & purificação , Relação Estrutura-Atividade , Calicreínas Teciduais/metabolismo
12.
Molecules ; 20(7): 12804-16, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26184153

RESUMO

Lung cancer is the leading cause of cancer deaths in the world. Disease stage is the most relevant factor influencing mortality. Unfortunately, most patients are still diagnosed at an advanced stage and their five-year survival rate is only 4%. Thus, it is relevant to identify novel drugs that can improve the treatment options for lung cancer. Natural products have been an important source for the discovery of new compounds with pharmacological potential including antineoplastic agents. We have previously isolated a prenylated benzophenone (7-epiclusianone) from Garcinia brasiliensis (Clusiaceae) that has several biological properties including antiproliferative activity against cancer cell lines. In continuation with our studies, the present work aimed to investigate the mechanisms involved with antiproliferative activity of 7-epiclusianone in A549 cells. Our data showed that 7-epiclusianone reduced the viability of A549 cells in a concentration-dependent manner (IC50 of 16.13 ± 1.12 µM). Cells were arrested in G1/S transition and apoptosis was induced. In addition, we observed morphological changes with cytoskeleton disorganization in consequence of the treatment. Taken together, the results showed that cell cycle arrest in G1/S transition is the main mechanism involved with antiproliferative activity of 7-epiclusianone. Our results are promising and open up the prospect of using this compound in further anticancer in vivo studies.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Benzofenonas/farmacologia , Benzoquinonas/farmacologia , Células Epiteliais/efeitos dos fármacos , Frutas/química , Garcinia/química , Mucosa Respiratória/efeitos dos fármacos , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Benzofenonas/química , Benzofenonas/isolamento & purificação , Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/ultraestrutura , Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Extratos Vegetais/química , Mucosa Respiratória/metabolismo , Mucosa Respiratória/ultraestrutura
13.
Rev. bras. farmacogn ; 25(3): 228-232, May-June 2015. tab, ilus
Artigo em Inglês | LILACS | ID: lil-757434

RESUMO

AbstractArrabidaea brachypoda Bureau, Bignoniaceae, known as "cipó-una", is widely used in traditional medicine in Southeastern and Northeastern Brazil for kidney stones and painful joints. This study was aimed at evaluating the anti-inflammatory proprieties of the oleanane-type triterpenoid 3β-estearioxy-olean-12-ene isolated from the roots of A. brachypoda. Carrageenan-induced paw oedema, formalin test and hot plate test were used to investigate the antiinflammatory activity of 3β-estearioxy-olean-12-ene in animals. We observed that 3β-estearioxy-olean-12-ene at doses of 5, 10 and 15 mg/kg p.o. demonstrated anti-inflammatory effects, by reduced (p < 0.05) paw oedema induced by carrageenan and by decreased (p < 0.05) licking time caused by a subplantar injection of formalin. In conclusion, 3β-estearioxy-olean-12-ene, a triterpene isolated from the roots of A. brachypoda, demonstrate anti-inflammatory effect in different tests. Thus, it may be useful in the treatment of inflammatory disorders, which supports previous claims of its traditional use.

14.
Planta Med ; 79(16): 1495-500, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24037589

RESUMO

The present study characterized the mechanisms involved in the vasodilator effect of two mono-oxygenated xanthones, 4-hydroxyxanthone and 4-methoxyxanthone. 9-Xanthenone, the base structure of xanthones, was used for comparison. 4-Hydroxyxanthone and 9-xanthenone induced a concentration-dependent and endothelium-independent vasodilator effect in arteries precontracted with phenylephrine (0.1 µmol ·â€ŠL-1) or KCl (50 mmol ·â€ŠL-1). 4-Methoxyxanthone induced a concentration-dependent vasodilator effect in arteries precontracted with phenylephrine, which was partially endothelium-dependent, and involved production of nitric oxide. In endothelium-denuded arteries precontracted with KCl, the vasodilator effect of 4-methoxyxanthone was abolished. The vasodilator effect of 4-hydroxyxanthone (96.22 ± 2.10 %) and 4-methoxyxanthone (96.57 ± 12.40 %) was significantly higher than observed with 9-xanthenone (53.63 ± 8.31 %). The presence of an oxygenated radical in position 4 made 4-hydroxyxanthone (pIC50 = 4.45 ± 0.07) and 4-methoxyxanthone (pIC50 = 5.04 ± 0.09) more potent as a vasodilator than 9-xanthenone (pIC50 = 3.92 ± 0.16). In addition, 4-methoxyxanthone was more potent than the other two xanthones. Ca2+ transients in vascular smooth muscle cells elicited by high K+ were abolished by 4-hydroxyxanthone and 9-xanthenone. The endothelium-independent effect of 4-methoxyxanthone was abolished by inhibition of K+ channels by tetraethylammonium. The current work shows that an oxygenated group in position 4 is essential to achieve Emax and to increase the potency of xanthones as vasodilators. Substitution of an OH by OCH3 in position 4 increases the potency of the vasodilator effect and changes the underling mechanism of action from the blockade of L-type calcium channels to an increase in NO production and activation of K+ channels.


Assuntos
Vasodilatadores/farmacologia , Xantonas/farmacologia , Animais , Aorta/efeitos dos fármacos , Cálcio/metabolismo , Endotélio Vascular/efeitos dos fármacos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Relação Estrutura-Atividade , Vasodilatadores/química , Xantonas/química
15.
PLoS One ; 8(8): e71759, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23951240

RESUMO

Previous studies have described the antispasmodic effect of mangiferin, a natural glucoside xanthone (2-C-ß-Dgluco-pyranosyl-1,3,6,7-tetrahydroxyxanthone) that is present in mango trees and other plants, but its mechanism of action remains unknown. The aim of this study was to examine the potential contribution of the nitric oxide-cyclic GMP pathway to the antispasmodic effect of mangiferin on isolated tracheal rings preparations. The functional effect of mangiferin on allergic and non-allergic contraction of guinea pig tracheal rings was assessed in conventional organ baths. Cultured tracheal rings were exposed to mangiferin or vehicle, and nitric oxide synthase (NOS) 3 and cyclic GMP (cGMP) levels were quantified using western blotting and enzyme immunoassays, respectively. Mangiferin (0.1-10 µM) inhibited tracheal contractions induced by distinct stimuli, such as allergen, histamine, 5-hydroxytryptamine or carbachol, in a concentration-dependent manner. Mangiferin also caused marked relaxation of tracheal rings that were precontracted by carbachol, suggesting that it has both anti-contraction and relaxant properties that are prevented by removing the epithelium. The effect of mangiferin was inhibited by the nitric oxide synthase inhibitor, Nω-nitro-L-arginine methyl ester (L-NAME) (100 µM), and the soluble guanylate cyclase inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) (10 µM), but not the adenylate cyclase inhibitor, 9-(tetrahydro-2-furyl)adenine (SQ22536) (100 µM). The antispasmodic effect of mangiferin was also sensitive to K⁺ channel blockers, such as tetraethylammonium (TEA), glibenclamide and apamin. Furthermore, mangiferin inhibited Ca²âº-induced contractions in K⁺ (60 mM)-depolarised tracheal rings preparations. In addition, mangiferin increased NOS3 protein levels and cGMP intracellular levels in cultured tracheal rings. Finally, mangiferin-induced increase in cGMP levels was abrogated by co-incubation with either ODQ or L-NAME. These data suggest that the antispasmodic effect of mangiferin is mediated by epithelium-nitric oxide- and cGMP-dependent mechanisms.


Assuntos
GMP Cíclico/metabolismo , Óxido Nítrico/metabolismo , Parassimpatolíticos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Traqueia/efeitos dos fármacos , Xantonas/farmacologia , Animais , Cálcio/metabolismo , Guanilato Ciclase/antagonistas & inibidores , Guanilato Ciclase/metabolismo , Cobaias , Masculino , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Bloqueadores dos Canais de Potássio/farmacologia , Traqueia/fisiologia
16.
Bioorg Med Chem ; 20(8): 2713-20, 2012 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-22401914

RESUMO

Six derivatives of guttiferone-A (LFQM-79, 80, 81, 82, 113 and 114) were synthesized and evaluated for their antimicrobial activity against the opportunistic or pathogenic fungi Candida albicans (ATCC 09548), Candida glabrata (ATCC 90030), Candida krusei (ATCC 6258), Candida parapsilosis (ATCC 69548), Candida tropicalis (ATCC 750), Cryptococcus neoformans (ATCC 90012), Trichophyton tonsurans, Microsporum gypseum and also against the opportunistic and pathogenic Gram-positive bacteria Staphylococcus aureus (ATCC 6538), Staphylococcus epidermidis (ATCC 12228), Bacillus cereus (ATCC 11778) and Gram-negative Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 9027), Salmonella typhimurium (ATCC 14028), Proteus mirabilis (ATCC 25933). The antimicrobial activities of derivatives were compared with guttiferone-A and they presented to be more potent than the original molecule and sometimes greater than standard drugs established in therapeutics. The current study showed that derivatives of guttiferone-A possess potent antimicrobial activity and are relatively non-cytotoxic, which reveal these new molecules as promising new drug prototype candidates, with innovative structural pattern.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Bactérias/efeitos dos fármacos , Benzofenonas/farmacologia , Fungos/efeitos dos fármacos , Antibacterianos/química , Antifúngicos/química , Bactérias/crescimento & desenvolvimento , Benzofenonas/síntese química , Benzofenonas/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fungos/crescimento & desenvolvimento , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Conformação Molecular , Estereoisomerismo , Relação Estrutura-Atividade
17.
J Med Food ; 15(2): 200-5, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22191630

RESUMO

Despite defenses by polymorphonuclear neutrophils in the host against invading agents, overproduction of oxidant species by phagocytes can lead to damage in the surrounding tissues. Several benzophenones have been shown to possess anti-inflammatory properties. The effect of the natural benzophenone 7-epiclusianone isolated from leaves of Garcinia brasiliensis was investigated by using in vitro antioxidant and ex vivo anti-inflammatory assays, focusing on the neutrophil respiratory burst and on the biochemical pathways involved. The bioactive extract, 7-epiclusianone, showed low in vitro antioxidant activity as evaluated by the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging assay, the reducing power test, or the chelating power assay. However, the benzophenone displayed potent activity in the ex vivo model of the neutrophil respiratory burst, inhibiting the generation of superoxide anions in a dose-dependent manner. When the respiratory burst was triggered by N-formyl-methionyl-leucyl-phenylalanine, a chemotactic peptide, the 50% effective concentration (EC(50)) was 41.18 µg/10(7) cells. When phagocytes were stimulated directly through protein kinase C via phorbol, the EC(50) was 34.3 µg/10(6) cells. The results indicated that 7-epiclusianone was able to down-regulate inflammatory phagocyte superoxide anion release through a mechanism controlled by tyrosine protein phosphorylation and by a direct stimulation of protein kinase C. These findings could lead to new therapeutic approaches for inflammation management and the development of new drugs.


Assuntos
Benzofenonas/farmacologia , Garcinia/química , Neutrófilos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Explosão Respiratória/efeitos dos fármacos , Superóxidos/metabolismo , Animais , Células Cultivadas , Masculino , Camundongos , Neutrófilos/metabolismo
18.
Eur J Pharmacol ; 670(1): 280-5, 2011 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-21924261

RESUMO

7-Epiclusianone, a natural prenylated benzophenone, was extracted from Garcinia brasiliensis Planch. & Triana (Clusiaceae), a native plant commonly known as bacupari and used in traditional Brazilian medicine for the treatment of inflammatory diseases. As a result of the wide spectrum of biological activities attributed to polyisoprenylated benzophenones, the aim of this study was to evaluate the analgesic and anti-inflammatory effects of 7-epiclusianone using two animal models. Carrageenan-induced paw oedema and peritonitis were used to investigate the anti-inflammatory activity of 7-epiclusianone in rats. The acetic acid-induced writhing, formalin and hot-plate tests were used to investigate its antinociceptive activity in mice. At test doses of 5, 10 and 15 mg/kg p.o., 7-epiclusianone had an anti-inflammatory effect as demonstrated by the reduction of paw oedema induced by carrageenan and the inhibition of leukocyte recruitment into the peritoneal cavity. At the same doses, 7-epiclusianone inhibited nociception induced by an intraperitoneal injection of acetic acid, observed by the decrease in the number of writhing episodes. Additionally, 7-epiclusianone decreased licking time caused by a subplantar injection of formalin. Moreover, the hot plate test produced a significant increase in latency reaction, demonstrating an antinociceptive effect. The experimental data demonstrated that the polyisoprenylated benzophenone 7-epiclusianone has remarkable anti-inflammatory and antinociceptive activities.


Assuntos
Benzofenonas/química , Benzofenonas/farmacologia , Benzoquinonas/química , Benzoquinonas/farmacologia , Garcinia/química , Prenilação , Ácido Acético/efeitos adversos , Analgésicos/química , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Benzofenonas/uso terapêutico , Benzoquinonas/uso terapêutico , Carragenina/efeitos adversos , Edema/induzido quimicamente , Edema/tratamento farmacológico , Temperatura Alta/efeitos adversos , Lipopolissacarídeos/efeitos adversos , Masculino , Camundongos , Medição da Dor , Peritonite/induzido quimicamente , Peritonite/tratamento farmacológico , Ratos
19.
J Med Food ; 14(6): 557-62, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21554130

RESUMO

The infections by protozoans of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The drugs of choice for the treatment of leishmaniasis are the pentavalent antimonials, which cause renal and cardiac toxicity. As part of a search for new drugs against leishmaniasis, we evaluated the in vitro Leishmania protease inhibition activity of extracts (hexanic, ethyl-acetate, and ethanolic) and fukugetin, a bioflavonoid purified from the ethyl-acetate extract of the pericarp of the fruit of Garcinia brasiliensis, a tree native to Brazilian forests. The isolated compound was characterized by using spectral analyses with nuclear magnetic resonance, mass spectroscopy, ultraviolet, and infrared techniques. The ethyl-acetate extract and the compound fukugetin showed significant activity as inhibitors of Leishmania's proteases, with mean (±SD) IC(50) (50% inhibition concentration of protease activity) values of 15.0±1.3 µg/mL and 3.2±0.5 µM/mL, respectively, characterizing a bioguided assay. In addition, this isolated compound showed no activity against promastigote and amastigote forms of L. (L.) amazonensis and mammalian cells. These results suggest that fukugetin is a potent protease inhibitor of L. (L.) amazonensis and does not cause toxicity in mammalian or Leishmania cells in vitro. This study provides new perspectives on the development of novel drugs that have leishmanicidal activity obtained from natural products and that target the parasite's proteases.


Assuntos
Antiprotozoários/farmacologia , Garcinia/química , Leishmania/efeitos dos fármacos , Leishmania/enzimologia , Extratos Vegetais/farmacologia , Inibidores de Proteases/farmacologia , Proteínas de Protozoários/antagonistas & inibidores , Animais , Brasil , Frutas/química , Humanos , Concentração Inibidora 50 , Leishmaniose/parasitologia , Peptídeo Hidrolases/metabolismo , Proteínas de Protozoários/metabolismo , Ratos
20.
J Ethnopharmacol ; 133(2): 396-401, 2011 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-20950679

RESUMO

AIM OF THE STUDY: Arrabidaea brachypoda (DC.) Bureau has been used to relieve general pain, painful joints and kidney stones in Brazilian folk medicine. Nevertheless, scientific information regarding this species is scarce; there are no reports related to its possible analgesic and anti-inflammatory effects. This study was aimed at evaluating the traditional use of Arrabidaea brachypoda root using in vivo inflammatory and nociceptive models. MATERIALS AND METHODS: Carrageenan-induced paw edema, peritonitis and fibrovascular tissue growth induced by s.c. cotton pellet implantation were used to investigate the anti-inflammatory activity of Arrabidaea brachypoda roots ethanolic extract (AbEE) in rats. Formalin and acetic acid-induced writhing tests were used to investigate the antinociceptive activity in mice. High-performance liquid chromatography (HPLC) was used to determine the fingerprint chromatogram of AbEE. RESULTS: The AbEE at test doses of 30-300 mg/kg p.o. demonstrated anti-inflammatory effects. AbEE reduced paw edema induced by carrageenan, inhibited leukocyte recruitment into the peritoneal cavity and, in the model of chronic inflammation using the cotton pellet-induced fibrovascular tissue growth in rats, significantly inhibited the formation of granulomatous tissue. The extracts at test doses of 30-300 mg/kg p.o. clearly demonstrated antinociceptive activity, except during the first phase of the formalin test. The presence of quercetin and phenolic compounds in the extract Arrabidaea brachypoda was confirmed using HPLC. CONCLUSION: Arrabidaea brachypoda ethanol extract markedly demonstrated anti-inflammatory action in rats and antinociceptive activity in mice, which supports the previous claims of traditional use.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Bignoniaceae/química , Analgésicos/isolamento & purificação , Animais , Anti-Inflamatórios não Esteroides/isolamento & purificação , Brasil , Edema/tratamento farmacológico , Etnofarmacologia , Granuloma de Corpo Estranho/tratamento farmacológico , Masculino , Medicina Tradicional , Camundongos , Medição da Dor , Peritonite/tratamento farmacológico , Fitoterapia , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Raízes de Plantas/química , Plantas Medicinais/química , Ratos , Ratos Wistar
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