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Lima, Gedson Rodrigues De Morais - One of the best experts on this subject based on the ideXlab platform.

  • Atividade gastroprotetora de Combretum duarteanum Cambess. (Combretaceae) em modelos animais
    Universidade Federal da Paraí­ba, 2011
    Co-Authors: Lima, Gedson Rodrigues De Morais
    Abstract:

    Combretum duarteanum Cambess, popularmente conhecida como mofumbo, é uma espécie exclusiva da América Latina, geralmente associada a ambientes da caatinga, com uso popular para fins medicinais, dentre elas para o tratamento de inflamação e infecções. Tais efeitos geralmente estão associados aos seus principais constituintes, dentre eles os flavonóides, taninos e terpenos. O extrato etanólico bruto (EEtOH-Cd) e a fase hexânica (FaHex-Cd) obtidos das folhas de C. duarteanum Cambess, foram avaliados quanto a sua toxicidade e efeitos farmacológicos frente a atividade gastroprotetora e cicatrizante, assim como os prováveis mecanismos de ação relacionados. A administração oral (v.o.) de 2000 mg/Kg do EEtOH-Cd, não provocou alterações no comportamento, nos pesos corporais e nos órgãos, bem como não ocorreram alterações no consumo de água, entretanto, o consumo de ração, foi reduzido no grupo dos animais machos. Não foram observadas alterações macroscópicas nos órgãos, sem ocorrência de mortes, sendo portanto, impossível determinar a DL50. O EEtOH-Cd e FaHex-Cd foram avaliados quanto à sua atividade gastroprotetora nos modelos de indução aguda de úlcera HCl/Etanol, etanol absoluto, estresse (imobilização e frio) e antiinflamatório não esteroidal (piroxicam) nas doses 62,5, 125, 250 e 500 mg/Kg (v.o.) e contensão do suco gástrico ( 250 mg/Kg v.o. e i.d.) em camundongos Swiss e ratos Wistar machos. No modelo HCl/etanol, o EEtOH-Cd (62,5 125, 250 e 500 mg/kg, v.o.) reduziu o índice de lesão ulcerativa (ILU) em 28, 36, 55 e 63 %, respectivamente. Também foi observado no modelo de etanol que o EEtOH-Cd e a FaHex-Cd (62,5 125, 250 e 500 mg/kg, v.o.) inibiram o ILU em 51, 48, 61, 45 e 37, 44, 79, 86 %, respectivamente. No modelo de estresse o EEtOH-Cd ( 125, 250 e 500 mg/kg, v.o.) reduziu o ILU em cerca de 44, 54 e 69% e a FaHex-Cd (62,5, 125, 250 e 500 mg/kg, v.o.) em cerca de 55, 56, 69 e 79 %. Na indução aguda de úlcera por AINE, as porcentagens de proteção para EEtOH-Cd ( 125, 250 e 500 mg/kg, v.o.) e FaHex-Cd ( 250 e 500 mg/kg, v.o.) foram 30, 42, 49 % e 43, 52 %, respectivamente. Nas úlceras induzidas por contensão do suco gástrico (ligadura de piloro) o EEtOH-Cd (250 mg/kg) e a FaHex-Cd (250 mg/kg) apresentaram proteção gástrica tanto por via oral (v.o.) (66 e 39 %) quanto por via intraduodenal (i.d.) (41 e 45 %), respectivamente. Tanto o EEtOH-Cd e FaHex-Cd não provocaram alterarações no volume e pH do suco gástrico. Na perspectiva de elucidar os prováveis mecanismos de ação envolvidos com a atividade gastroprotetora do EEtOH-Cd (250 mg/kg) e da FaHex-Cd (250 mg/kg), foram avaliadas as participações do muco aderido a mucosa, do óxido nítrico e dos grupamentos sulfidrílicos. De acordo com os resultados obtidos o efeito gastroprotetor não inclui a participação do muco, porém é dependente da participação do óxido nítrico e dos compostos sulfidrílicos. No modelo de úlcera induzida por ácido acético, o tratamento crônico com o EEtOH-Cd (250 mg/kg, v.o.) ou FaHex-Cd (250 mg/kg, v.o.) reduziu a área de lesão ulcerativa em 38 e 48 %, respectivamente. Neste modelo, durante os 14 dias de tratamento, foi observado que o EEtOH-Cd promoveu aumento na ingesta de água e ração. Portanto, estes dados indicam C. duarteanum apresenta atividade gastroprotetora podendo ter a participação dos grupamentos sulfidrilas e da via do óxido nítrico, bem como o envolvimento de fatores de crescimento no processo de cicatrização induzido pelos constituintes químicos presentes nas amostras vegetais testadas.Combretum duarteanum Cambess is popularly known as mofumbo, a unique species from Latin America, usually associated with arid environments. This species belongs to Combretaceae family, known in various continents of the world for its popular use in treatment of inflammation and infections, its effects are usually associated with its major constituents, flavonoids, tannins and terpenes. The crude ethanol extract (Cd-EtOHE) and the hexane phase (Cd-HexP) obtained from the leaves of C. duarteanum Cambess were evaluated for toxicity and pharmacological effects against gastroprotective activity and healing, as well as the likely mechanisms of related actions. Oral administration (p.o.) 2000 mg/Kg of Cd-EtOHE, in mice did not show behavioral changes. Regarding water intake, was observed that the extract did not cause significant changes in both the groups, both in males and in females. However the feed intake was observed to decrease significantly in the group of males treated. No animal died and no significant macroscopic changes in daily body or organ weight were observed, making it impossible to determine the LD50. The Cd-EtOHE and Cd-HexP were assessed for their gastroprotective activity in models of acute ulcer induced by HCl/ ethanol, absolute ethanol, stress (immobilization and cold), nonsteroidal anti-inflammatory drug (piroxicam) at doses with 62.5, 125, 250 and 500 mg / kg (p.o.) and pylorus ligature (250 mg/kg v.o. and i.d.) in Swiss mice and male Wistar rats. In the model HCl / ethanol, Cd-EtOHE (62.5 125, 250 and 500 mg / kg, p.o.) significantly reduced the ULI the ulcerative lesion index in 28, 36, 55 and 63% respectively. It was also observed in the ethanol model Cd-EtOHE and Cd-HexP (62.5 125, 250 and 500 mg/kg, p.o.) significantly inhibited the ULI in 51, 48, 61, 45 and 37, 44, 79, 86 %, respectively. In the stress model Cd-EtOHE (125, 250 and 500 mg / kg, po) reduced the ULI in 44, 54 and 69% and Cd-HexP (62.5, 125, 250 and 500 mg / kg po) was about 55, 56, 69 and 79%.In the NSAID-induced ulcers, the percentages of protection for Cd-EtOHE (125, 250 and 500 mg / kg, po) and Cd-HexP (250 and 500 mg / kg, po) were 30, 42, 49 and 43%, 52% , respectively. The results obtained front of the restraint of gastric secretion (pylorus ligation) have shown that Cd-EtOHE (250 mg/kg) or Cd-HexP (250 mg/kg), showed protection both given orally (p.o.) (66 and 39%) or by intraduodenal route (i.d.) (41 and 45%), respectively. The data showed that the Cd-EtOHE and Cd-HexP, did not promote changes in pH and the volume of gastric juice. To evaluate the gastroprotective activity and the likely mechanisms of related actions of the Cd-EtOHE (250 mg / kg) and Cd-HexP (250 mg / kg) were carried out experimental protocols to assess the contribution of mucus, nitric oxide and sulfhydryl groups. According to the obtained results, it is possible to suggest that the gastroprotective effect does not include the mucus participation, but is dependent on the nitric oxide and sulfhydryl compounds participation. In the model of acetic acid induced ulcer, chronic treatment with Cd-EtOHE (250 mg / kg, po) and Cd-HexP (250 mg / kg, p.o.) significantly reduced the ulcerative area in 38 and 48%, respectively. During the 14 days of treatment, we observed that the Cd-EtOHE increased the water and food intake, but for Cd-HexP this effect was not observed. These results suggest that the Cd-EtOHE and Cd-HexP displays gastroprotective activity, which are related the participation of NO, an increase in endogenous SH compounds, as well as the growth factors involvement in the healing process induced by the chemical constituents present in the vegetable samples tested

  • Atividade gastroprotetora de Combretum duarteanum Cambess. (Combretaceae) em modelos animais
    'Portal de Periodicos UFPB', 2011
    Co-Authors: Lima, Gedson Rodrigues De Morais
    Abstract:

    Combretum duarteanum Cambess is popularly known as mofumbo, a unique species from Latin America, usually associated with arid environments. This species belongs to Combretaceae family, known in various continents of the world for its popular use in treatment of inflammation and infections, its effects are usually associated with its major constituents, flavonoids, tannins and terpenes. The crude ethanol extract (Cd-EtOHE) and the hexane phase (Cd-HexP) obtained from the leaves of C. duarteanum Cambess were evaluated for toxicity and pharmacological effects against gastroprotective activity and healing, as well as the likely mechanisms of related actions. Oral administration (p.o.) 2000 mg/Kg of Cd-EtOHE, in mice did not show behavioral changes. Regarding water intake, was observed that the extract did not cause significant changes in both the groups, both in males and in females. However the feed intake was observed to decrease significantly in the group of males treated. No animal died and no significant macroscopic changes in daily body or organ weight were observed, making it impossible to determine the LD50. The Cd-EtOHE and Cd-HexP were assessed for their gastroprotective activity in models of acute ulcer induced by HCl/ ethanol, absolute ethanol, stress (immobilization and cold), nonsteroidal anti-inflammatory drug (piroxicam) at doses with 62.5, 125, 250 and 500 mg / kg (p.o.) and pylorus ligature (250 mg/kg v.o. and i.d.) in Swiss mice and male Wistar rats. In the model HCl / ethanol, Cd-EtOHE (62.5 125, 250 and 500 mg / kg, p.o.) significantly reduced the ULI the ulcerative lesion index in 28, 36, 55 and 63% respectively. It was also observed in the ethanol model Cd-EtOHE and Cd-HexP (62.5 125, 250 and 500 mg/kg, p.o.) significantly inhibited the ULI in 51, 48, 61, 45 and 37, 44, 79, 86 %, respectively. In the stress model Cd-EtOHE (125, 250 and 500 mg / kg, po) reduced the ULI in 44, 54 and 69% and Cd-HexP (62.5, 125, 250 and 500 mg / kg po) was about 55, 56, 69 and 79%.In the NSAID-induced ulcers, the percentages of protection for Cd-EtOHE (125, 250 and 500 mg / kg, po) and Cd-HexP (250 and 500 mg / kg, po) were 30, 42, 49 and 43%, 52% , respectively. The results obtained front of the restraint of gastric secretion (pylorus ligation) have shown that Cd-EtOHE (250 mg/kg) or Cd-HexP (250 mg/kg), showed protection both given orally (p.o.) (66 and 39%) or by intraduodenal route (i.d.) (41 and 45%), respectively. The data showed that the Cd-EtOHE and Cd-HexP, did not promote changes in pH and the volume of gastric juice. To evaluate the gastroprotective activity and the likely mechanisms of related actions of the Cd-EtOHE (250 mg / kg) and Cd-HexP (250 mg / kg) were carried out experimental protocols to assess the contribution of mucus, nitric oxide and sulfhydryl groups. According to the obtained results, it is possible to suggest that the gastroprotective effect does not include the mucus participation, but is dependent on the nitric oxide and sulfhydryl compounds participation. In the model of acetic acid induced ulcer, chronic treatment with Cd-EtOHE (250 mg / kg, po) and Cd-HexP (250 mg / kg, p.o.) significantly reduced the ulcerative area in 38 and 48%, respectively. During the 14 days of treatment, we observed that the Cd-EtOHE increased the water and food intake, but for Cd-HexP this effect was not observed. These results suggest that the Cd-EtOHE and Cd-HexP displays gastroprotective activity, which are related the participation of NO, an increase in endogenous SH compounds, as well as the growth factors involvement in the healing process induced by the chemical constituents present in the vegetable samples tested.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPESCombretum duarteanum Cambess, popularmente conhecida como mofumbo, é uma espécie exclusiva da América Latina, geralmente associada a ambientes da caatinga, com uso popular para fins medicinais, dentre elas para o tratamento de inflamação e infecções. Tais efeitos geralmente estão associados aos seus principais constituintes, dentre eles os flavonóides, taninos e terpenos. O extrato etanólico bruto (EEtOH-Cd) e a fase hexânica (FaHex-Cd) obtidos das folhas de C. duarteanum Cambess, foram avaliados quanto a sua toxicidade e efeitos farmacológicos frente a atividade gastroprotetora e cicatrizante, assim como os prováveis mecanismos de ação relacionados. A administração oral (v.o.) de 2000 mg/Kg do EEtOH-Cd, não provocou alterações no comportamento, nos pesos corporais e nos órgãos, bem como não ocorreram alterações no consumo de água, entretanto, o consumo de ração, foi reduzido no grupo dos animais machos. Não foram observadas alterações macroscópicas nos órgãos, sem ocorrência de mortes, sendo portanto, impossível determinar a DL50. O EEtOH-Cd e FaHex-Cd foram avaliados quanto à sua atividade gastroprotetora nos modelos de indução aguda de úlcera HCl/Etanol, etanol absoluto, estresse (imobilização e frio) e antiinflamatório não esteroidal (piroxicam) nas doses 62,5, 125, 250 e 500 mg/Kg (v.o.) e contensão do suco gástrico ( 250 mg/Kg v.o. e i.d.) em camundongos Swiss e ratos Wistar machos. No modelo HCl/etanol, o EEtOH-Cd (62,5 125, 250 e 500 mg/kg, v.o.) reduziu o índice de lesão ulcerativa (ILU) em 28, 36, 55 e 63 %, respectivamente. Também foi observado no modelo de etanol que o EEtOH-Cd e a FaHex-Cd (62,5 125, 250 e 500 mg/kg, v.o.) inibiram o ILU em 51, 48, 61, 45 e 37, 44, 79, 86 %, respectivamente. No modelo de estresse o EEtOH-Cd ( 125, 250 e 500 mg/kg, v.o.) reduziu o ILU em cerca de 44, 54 e 69% e a FaHex-Cd (62,5, 125, 250 e 500 mg/kg, v.o.) em cerca de 55, 56, 69 e 79 %. Na indução aguda de úlcera por AINE, as porcentagens de proteção para EEtOH-Cd ( 125, 250 e 500 mg/kg, v.o.) e FaHex-Cd ( 250 e 500 mg/kg, v.o.) foram 30, 42, 49 % e 43, 52 %, respectivamente. Nas úlceras induzidas por contensão do suco gástrico (ligadura de piloro) o EEtOH-Cd (250 mg/kg) e a FaHex-Cd (250 mg/kg) apresentaram proteção gástrica tanto por via oral (v.o.) (66 e 39 %) quanto por via intraduodenal (i.d.) (41 e 45 %), respectivamente. Tanto o EEtOH-Cd e FaHex-Cd não provocaram alterarações no volume e pH do suco gástrico. Na perspectiva de elucidar os prováveis mecanismos de ação envolvidos com a atividade gastroprotetora do EEtOH-Cd (250 mg/kg) e da FaHex-Cd (250 mg/kg), foram avaliadas as participações do muco aderido a mucosa, do óxido nítrico e dos grupamentos sulfidrílicos. De acordo com os resultados obtidos o efeito gastroprotetor não inclui a participação do muco, porém é dependente da participação do óxido nítrico e dos compostos sulfidrílicos. No modelo de úlcera induzida por ácido acético, o tratamento crônico com o EEtOH-Cd (250 mg/kg, v.o.) ou FaHex-Cd (250 mg/kg, v.o.) reduziu a área de lesão ulcerativa em 38 e 48 %, respectivamente. Neste modelo, durante os 14 dias de tratamento, foi observado que o EEtOH-Cd promoveu aumento na ingesta de água e ração. Portanto, estes dados indicam C. duarteanum apresenta atividade gastroprotetora podendo ter a participação dos grupamentos sulfidrilas e da via do óxido nítrico, bem como o envolvimento de fatores de crescimento no processo de cicatrização induzido pelos constituintes químicos presentes nas amostras vegetais testadas

Jeancharles Chapuis - One of the best experts on this subject based on the ideXlab platform.

  • antineoplastic agents 338 the cancer cell growth inhibitory constituents of terminalia arjuna Combretaceae
    Journal of Ethnopharmacology, 1996
    Co-Authors: George R Pettit, Jean M Schmidt, Michael S Hoard, Dennis L Doubek, Robin K Pettit, Larry P Tackett, Jeancharles Chapuis
    Abstract:

    By means of bioassay-guided separation methods, the cancer cell growth inhibitory constituents residing in the bark, stem and leaves of the Mauritius medicinal plant Terminalia arjuna (Combretaceae) were examined. The cancer cell line active components were found to be gallic acid, ethyl gallate, and the flavone luteolin. Only gallic acid was previously known to occur in this plant. Luteolin has a well established record of inhibiting various cancer cell lines and may account for most of the rationale underlying the use of T. arjuna in traditional cancer treatments. Luteolin was also found to exhibit specific activity against the pathogenic bacterium Neisseria gonorrhoeae.

David R Katerere - One of the best experts on this subject based on the ideXlab platform.

  • phytochemical and antimicrobial investigations of stilbenoids and flavonoids isolated from three species of Combretaceae
    Fitoterapia, 2012
    Co-Authors: David R Katerere, Alexander I Gray, Robert J Nash, Roger D Waigh
    Abstract:

    The antimicrobial activity and chemistry of the African Combretaceae has been well studied in recent years. The present study aimed to investigate the phytochemistry and antimicrobial activity of lesser known members of this family viz. C. hereroense, C. apiculatum and C. collinum. Pulverized leaves of C. collinum and C. apiculatum, and the fruit of C. hereroense were extracted with organic solvents and subjected to preparative chromatography. Seventeen phenolic constituents including four phenanthrenes from the fruit of C. hereroense and two known bibenzyls (including a combretastatin) from the leaves of C. collinum were isolated. The compounds were then subsequently tested for their antimicrobial activity against Candida albicans, Mycobacterium fortuitum, Staphylococcus aureus, Escherichia coli and Proteus vulgaris. Pinocembrin showed excellent activity against C. albicans (MIC - 6.25 μg/ml), superior to that of the positive control, fluconazole and against S. aureus (MIC - 12.5 mg/ml). The phenanthrenes (compounds 1, 2, 3 and 5) showed some activity against M. fortuitum and S. aureus with a uniform MIC of 25 μg/ml. From this study it was evident that most stilbenoids and flavonoids from the selected Combretaceae have little or no antimicrobial activity.

  • the biological activity and chemistry of the southern african Combretaceae
    Journal of Ethnopharmacology, 2008
    Co-Authors: J N Eloff, David R Katerere, L J Mcgaw
    Abstract:

    Abstract Aim of the study Members of the Combretaceae family are widely traded in the traditional medicine market in southern Africa. The family is also used for medicinal purposes in the rest of Africa and Asia for close to 90 medicinal indications. Many of these indications are related to treating infections. This contribution summarizes work done to date and identifies avenues for future research. Materials and methods Substantial work has already been done on the chemistry of especially Combretum and Terminalia species over many years. During the last decade we have focussed on bio-assay guided isolation of biologically active compounds with the aim of producing new effective antimicrobial products. Results and discussion Methods developed to facilitate this process and data on 25 compounds isolated from 7 species are presented. The large majority of compounds isolated were known, but the biological activities were not known. In practically all cases the antibacterial or antifungal activity of compounds isolated were much lower than expected from the activity of the crude extracts. It appears that synergism plays a role in antimicrobial activity of plant extracts and that the hope of isolating a single compound that can be used as a new agent to address antibiotic resistance has been frustrated. By simple manipulation such as selective extraction the activity of some crude extracts could however, be increased substantially and this offers a new approach to address antibiotic resistance via the herbal medicine industry. Practically all extracts obtained using intermediate polarity extractants had reasonable to very good activity with MICs as low as 40 μg/ml, validating the traditional use for infectious diseases. Aqueous extracts however, generally had hardly any activity. Conclusions The Combretaceae contains a diversity of antimicrobial compounds. Because poor people usually have only water available as extractant, it raises the question how plants growing in poor rural communities can be used to treat infections more effectively, and what the mechanism of activity of aqueous extracts used to treat infections in traditional medicine are.

  • isolation of an antibacterial stilbene from combretum woodii Combretaceae leaves
    African Journal of Biotechnology, 2005
    Co-Authors: J N Eloff, J O Famakin, David R Katerere
    Abstract:

    Acetone extracts of C. woodii leaf powder was separated by solvent-solvent partition into six fractions. The highest total activity was in the chloroform fraction. This fraction contained mainly one compound active against S. aureus. This compound was isolated by bioassay-guided fractionation using silica gel open column chromatography and identified by nuclear magnetic resonance (NMR) and mass spectroscopy (MS) as the stilbene 2’,3’,4-trihydroxyl-3,5,4’-trimethoxybibenzyl (combretastatin B5) previously isolated from the seeds of C. kraussii. It showed significant activity against S. aureus with an MIC of 16 μ μ μ μg/ml but with lower activity towards P. aeruginosa (125 μg/ml), E. faecalis (125 μg/ml) and slight activity against E. coli. This is the first report of the antimicrobial activity of combretastatin B5. Its concentration in the leaves was in the order of 5-10 mg/g which makes the use of non-polar leaf extracts a viable proposition in treating some infections, particularly in resource-poor settings.

  • biological activity of five antibacterial flavonoids from combretum erythrophyllum Combretaceae
    Journal of Ethnopharmacology, 2004
    Co-Authors: Nataly Martini, David R Katerere, J N Eloff
    Abstract:

    Preliminary studies with Combretum erythrophyllum showed antimicrobial activity against Gram-positive and Gram-negative bacteria. Seven antibacterial flavonoids were subsequently isolated by bioassay-guided fractionation, i.e. apigenin; genkwanin; 5-hydroxy-7,4'-dimethoxyflavone, rhamnocitrin; kaempferol; quercetin-5,3'-dimethylether; rhamnazin. All compounds had good activity against Vibrio cholerae and Enterococcus faecalis, with MIC values in the range of 25-50 microg/ml. Rhamnocitrin and quercetin-5,3'-dimethylether also inhibited Micrococcus luteus and Shigella sonei at 25 microg/ml. With the exception of 5-hydroxy-7,4'-dimethoxy-flavone the flavonoids were not toxic towards human lymphocytes. This compound is potentially toxic to human cells and exhibited the poorest antioxidant activity whereas rhamnocitrin and rhamnazin exhibited strong antioxidant activity. Genkwanin; rhamnocitrin; quercetin-5,3'-dimethylether; rhamnazin had a higher anti-inflammatory activity than the positive control mefenamic acid. Although these flavonoids are known, this is the first report of biological activity with several of these compounds.

  • antimicrobial activity of pentacyclic triterpenes isolated from african Combretaceae
    Phytochemistry, 2003
    Co-Authors: David R Katerere, Alexander I Gray, Robert J Nash, Roger D Waigh
    Abstract:

    Four pentacyclic tritepenes were isolated from Combretum imberbe Engl. & Diels, of which two are novel glycosidic derivatives of 1α,3β,23-trihydroxyolean-12-en-29-oic acid (hydroxyimberbic acid). Terminalia stuhlmannii Engl. & Diels stem bark yielded two glycosides of hydroxyimberbic acid, one of which is reported for the first time. The structures of the isolated compounds were elucidated by spectroscopic methods. Several of the compounds had antibacterial activity, imberbic acid showing particularly potent activity against Mycobacterium fortuitum and Staphylococcus aureus.

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P Bouchet - One of the best experts on this subject based on the ideXlab platform.