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1.
Int J Mol Sci ; 18(9)2017 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-28906474

RESUMO

Compound 8-C-rhamnosyl apigenin (8CR) induced a moderate reduction in the enzymatic activity of secretory phospholipase A2 (sPLA2) from Crotalus durissus terrificus and cytosolic phospholipase A2 (cPLA2), but the compound also significantly inhibited the enzymatic activity of the enzyme cyclooxygenase. In vitro assays showed that the compound induced a slight change in the secondary structure of sPLA2 from Crotalus durissus terrificus snake venom. In vivo assays were divided into two steps. In the first step, the 8CR compound was administered by intraperitoneal injections 30 min prior to administration of sPLA2. In this condition, 8CR inhibited edema and myonecrosis induced by the sPLA2 activity of Crotalus durissus terrificus in a dose-dependent manner by decreasing interleukin-1ß (IL-1ß), tumor necrosis factor α (TNF-α), prostaglandin E2 (PGE2), and lipid peroxidation. This has been demonstrated by monitoring the levels of malondialdehyde (MDA) in rat paws after the course of edema induced by sPLA2. These results, for the first time, show that sPLA2 of Crotalus durissus terrificus venom induces massive muscle damage, as well as significant edema by mobilization of cyclooxygenase enzymes. Additionally, its pharmacological activity involves increased lipid peroxidation as well as TNF-α and IL-1ß production. Previous administration by the peritoneal route has shown that dose-dependent 8CR significantly decreases the enzymatic activity of cyclooxygenase enzymes. This resulted in a decrease of the amount of bioactive lipids involved in inflammation; it also promoted a significant cellular protection against lipid peroxidation. In vivo experiments performed with 8CR at a concentration adjusted to 200 µg (8 mg/kg) of intraperitoneal injection 15 min after sPLA2 injection significantly reduced sPLA2 edema and the myotoxic effect induced by sPLA2 through the decrease in the enzymatic activity of cPLA2, cyclooxygenase, and a massive reduction of lipid peroxidation. These results clearly show that 8CR is a potent anti-inflammatory that inhibits cyclooxygenase-2 (COX-2), and it may modulate the enzymatic activity of sPLA2 and cPLA2. In addition, it was shown that Crotalus durissus terrificus sPLA2 increases cell oxidative stress during edema and myonecrosis, and the antioxidant properties of the polyphenolic compound may be significant in mitigating the pharmacological effect induced by sPLA2 and other snake venom toxins.


Assuntos
Apigenina/farmacologia , Edema/tratamento farmacológico , Peperomia/química , Extratos Vegetais/farmacologia , Doença Aguda , Animais , Apigenina/química , Biomarcadores , Ciclo-Oxigenase 2/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/etiologia , Edema/metabolismo , Edema/patologia , Mediadores da Inflamação/metabolismo , Estrutura Molecular , Fosfolipases A2 Secretórias/metabolismo , Extratos Vegetais/química , Ratos
2.
Rev. bras. farmacogn ; 27(1): 59-66, Jan.-Feb. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-843792

RESUMO

ABSTRACT The effects of the hexanic extracts of the fruits and flowers of Clusia fluminensis Planch. & Triana, Clusiaceae, as well as their main constituents, the triterpene lanosterol and the benzophenone clusianone, were evaluated on hemipterans Dysdercus peruvianus and Oncopeltus fasciatus. The topical treatments of insects with the hexanic extracts significantly affected the survival of O. fasciatus, but not that of D. peruvianus. Concomitantly, extracts delayed the development of both hemipterans. Moreover, isolated lanosterol significantly reduced both the survival and development of O. fasciatus and D. peruvianus, while clusianone only reduce the survival of D. peruvianus and marginally inhibited the development of both insects. The results show the specific activity of lanosterol and clusianone against the two evaluated insect species and indicate the potential of compounds derived from C. fluminensis for the development of specific biopesticides for the control of agricultural pests. Subsequent work will examine the mode of action of lanosterol and clusianone isolates from C. fluminensis.

3.
J Nat Prod ; 77(8): 1881-6, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25051336

RESUMO

To determine the absolute configuration of 3-ishwarone, the experimental electronic circular dichroism (ECD), electronic dissymmetry factor (EDF), optical rotatory dispersion (ORD), vibrational circular dichroism (VCD), and vibrational dissymmetry factor (VDF) spectra of (+)-3-ishwarone are analyzed with the corresponding density functional theoretical predictions for different diastereomers. ECD and ORD spectra by themselves could not facilitate the determination of the absolute configuration of this molecule. However, the magnitude of the experimental EDF of (+)-3-ishwarone is found to match better with that predicted for the (1R,2S,4S,5R,9R,11R) diastereomer. The analyses of similarity measures between experimental and predicted spectra for VCD and VDF clearly suggested that the absolute configuration of (+)-3-ishwarone is (1R,2S,4S,5R,9R,11R).


Assuntos
Sesquiterpenos/química , Algoritmos , Brasil , Dicroísmo Circular , Estrutura Molecular , Dispersão Óptica Rotatória , Peperomia/química , Componentes Aéreos da Planta/química , Estereoisomerismo
4.
Molecules ; 17(9): 11056-66, 2012 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-22976469

RESUMO

Essential oils of Duguetia lanceolata barks, obtained at 2 (T2) and 4 h (T4), were identified by gas chromatography and gas chromatography/mass spectrometry. ß-elemene (12.7 and 14.9%), caryophyllene oxide (12.4 and 10.7%) and ß-selinene (8.4 and 10.4%) were the most abundant components in T2 and T4, respectively. The essential oils inhibited the growth of Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli and Candida albicans. The essential oils were cytotoxic against brine shrimp. The extraction time influenced the chemical composition and biological activities of essential oils obtained from the barks of D. lanceolata.


Assuntos
Annonaceae/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Artemia/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Testes de Sensibilidade Microbiana , Óleos Voláteis/toxicidade , Casca de Planta/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/metabolismo , Streptococcus pyogenes/efeitos dos fármacos , Streptococcus pyogenes/crescimento & desenvolvimento , Streptococcus pyogenes/metabolismo
5.
Rev. bras. farmacogn ; 18(supl): 709-712, Dec. 2008. ilus, tab
Artigo em Português | LILACS | ID: lil-509449

RESUMO

The family Piperaceae encompasses 5 genera, Piper, Peperomia, Pothomorphe, Ottonia and Sarcorhachis, and approximately 2,000 species widely distributed in the tropical and subtropical regions of the world. Most of the Ottonia species are native to Brazil and they are used in folk medicine as diuretic, salivating, and anaesthetic. Chemical studies of non-polar fractions from leaves and roots of Ottonia anisum Sprengel lead to the isolation of an arylbutanoic metabolite, the 1-butyl-3,4-methylenedioxybezene.


A família Piperaceae é formada por 5 gêneros, Piper, Peperomia, Pothomorphe, Ottonia e Sarcorhachis, com cerca de 2000 espécies de ampla distribuição nas regiões tropicais e subtropicais do mundo. Das 23 espécies descritas para o gênero Ottonia, a maioria é nativa do Brasil. Essas plantas são popularmente utilizadas no país como diuréticas, salivantes e anestésicas. O estudo químico dos extratos apolares de folhas e de raízes de Ottonia anisum Sprengel levou aoisolamento de um componente majoritário identifi cado como o derivado arilbutanoídico: 1-butil-3,4-metilenodioxibeneno.

6.
Rev. bras. farmacogn ; 18(supl): 769-776, Dec. 2008. ilus
Artigo em Português | LILACS | ID: lil-509459

RESUMO

Ageratum fastigiatum (Gardn.) R. M. King et H. Rob. (Asteraceae), conhecido como "matapasto", é uma planta usada na medicina popular como cicatrizante e antimicrobiano. O objetivo deste trabalho foi realizar caracterização morfoanatômica da folha, dos ramos e da raiz de A. fastigiatum. Secções transversais e paradérmicas, coradas com safranina/azul de astra e azul de toluidina foram analisadas ao microscópio. As folhas são alternas ou fasciculadas; a inflorescência é constituída de capítulos; as flores com corola lilás; ausência de pápus. A raiz apresenta crescimento secundário na zona de ramificação com estruturas secretoras. O caule possui epiderme uniestratificada, estômatos, tricomas tectores simples e tricomas glandulares capitados. O pecíolo exibe contorno côncavo-convexo e a epiderme é unisseriada. A lâmina foliar é anfiestomática e o mesófilo dorsiventral. A epiderme possui células de contorno sinuoso e os estômatos são do tipo anomocítico. Os caracteres morfoanatômicos permitiram estabelecer parâmetros para identificação do A. fastigiatum.


Ageratum fastigiatum (Gardn.) R. M. King et H. Rob. (Asteraceae), known as "matapasto", is a plant used in the popular medicine as cicatrizant and antimicrobial. The aim of this work was to perform a morpho-anatomical characterization of the leaves, the stems and the roots from A. fastigiatum. Transversal and paradermic sections, stained with astra safranin/blue and toluidine blue were analyzed under a microscope. The leaves are alternate or fasciculate; the inflorescence is constituted of chapters; the flowers with lilac corolla; papus is absence. The root presents secondary growth in the ramification area with secretor structures. The stem possesses epidermis unistratified, stomata, simple non-glandular trichomes and capitates glandular trichomes. The petiole exhibits concave-convex outline and the epidermis is uniseriate. The blade leaf is hypostomatic; the mesophyll is dorsiventral. The epidermis possesses cells of sinuous outline and the stomata of the anomocytic type. The morpho-anatomical characters allowed establishing parameters for identification of A. fastigiatum.

7.
Rev. bras. farmacogn ; 18(3): 430-435, jul.-set. 2008. tab
Artigo em Português | LILACS | ID: lil-496118

RESUMO

O presente trabalho investigou as propriedades antinociceptiva, antiinflamatória e antiulcerogênica do extrato etanólico dos galhos de E. erythropappus. Foram realizados os testes de contorções abdominais induzidas por ácido acético; tempo da lambida da pata induzida por formalina; placa quente; edema de pata induzido por carragenina; lesões ulcerativas induzidas por indometacina e etanol. As doses de 50, 100 e 200 mg/kg inibiram as contorções em 43,07 por cento, 69,34 por cento e 70,07 por cento, respectivamente. O tempo da lambida da pata foi reduzido em ambas as fases nas doses testadas, enquanto o tempo de latência da placa quente teve efeito significativo na dose de 200 mg/kg. O edema de pata foi reduzido em 23,81 por cento (100 mg/kg) e 47,62 por cento (200 mg/kg). O índice ulcerativo das lesões induzidas por indometacina foi reduzido na dose de 100 mg/kg e 200 mg/kg, enquanto a dose de 200 mg/kg teve efeito significativo sobre o volume e o pH do suco gástrico. O índice ulcerativo e o volume do suco gástrico, induzidos por etanol, foram reduzidos na dose de 200 mg/kg, enquanto o pH do suco gástrico aumentou nas doses de 100 e 200 mg/kg. Os resultados indicam que o extrato etanólico de E. erythropappus avaliado pode constituir alvo potencial para uso em terapias da dor, da inflamação e de úlcera.


The present work investigated the antinociceptive, anti-inflammatory and antiulcerogenic activities of Eremanthus erythropappus ethanol extract. The tests were carried out by acetic acid writhing, paw licking induced by formalin, hot plate, indomethacin- and ethanol-induced ulcer. The doses of 50, 100 and 200 mg/kg inhibited the contortions in 43.07, 69.34 and 70.07 percent, respectively. Both phases of paw lick were reduced at the tested doses, while reaction time at hot plate had significant effect at 200 mg/kg. The paw edema was decreased in 23.81 percent (100 mg/kg) and 47.62 percent (200 mg/kg). The index of ulceration induced by indomethacin was reduced at the doses of 100 and 200 mg/kg, while 200 mg/kg decreased the gastric volume and pH. The index of ulceration and gastric volume induced by ethanol was reduced at 200 mg/kg, while the pH increased at 100 and 200 mg/kg. The results indicate that the ethanol extract from E. erythropappus may constitute a potential target for the use in therapies of the pain, inflammation and ulcer.

8.
Fitoterapia ; 76(6): 562-6, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15970398

RESUMO

Licanolide (3beta-hydroxylupane-20,28-olide), a novel triterpene lactone with new stereochemical pattern, was isolated from fresh fruits of Licania tomentosa in addition to betulinic and palmitoleic acid. The structure elucidation was based on spectroscopic methods including two-dimensional NMR experiments (HSQC, HMBC and NOESY).


Assuntos
Chrysobalanaceae , Lactonas/química , Fitoterapia , Extratos Vegetais/química , Triterpenos/química , Frutas , Humanos , Espectroscopia de Ressonância Magnética , Estrutura Molecular
9.
Ciênc. cult. (Säo Paulo) ; 49(5/6): 331-8, Sept.-Dec. 1997. tab, graf
Artigo em Inglês | LILACS | ID: lil-214093

RESUMO

Most plant bearing pyrrolizidine alkaloids (PAs) are toxic to men and animals. These natural products are recognized to be hepatotoxic, pneumotoxic, carcinogenic and mutagenic. Thus, the presence of toxic pyrrolizidine alkaloids in certain medicinal plants entails a serious health risk. Moreover, people are exposed to undetermined toxicity hazards of pyrrolizidine alkaloid-containing plants due to the consumption of milk and meat from chronically PA-poisoned animals and honey from wild bees. Symphytum officinale (comfrey) has been used freely as tea, topical cream, salad and beverage. This is a clear and actual example of how lack of knowledge about chemistry and toxicology of a plant made easy its spreading in the consumer society as beneficial and safe.


Assuntos
Humanos , Animais , Carcinógenos , Intoxicação por Plantas , Plantas Medicinais/química , Alcaloides de Pirrolizidina/intoxicação , Mel/intoxicação , Carne/intoxicação , Leite/intoxicação , Plantas Medicinais/intoxicação , Alcaloides de Pirrolizidina/química , Alcaloides de Pirrolizidina/metabolismo
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