Antidiarrhoeal effects of Mikania glomerata Spreng. (Asteraceae) leaf extract in mice

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effect of Mikania glomerata (Asteraceae) leaf extract combined with anti-venom serum on experimental Crotalus durissus (Squamata: Viperidae) envenomation in rats

Crotalic envenomation represents the highest number of deaths when compared to other snakebite envenomations of medical interest. Crotalic venom has important characteristics such as neurotoxicity, myotoxicity, nephrotoxicity, and clotting and hemolytic action. We evaluated the clinical and laboratory aspects of Crotalus durissus terrificus experimental envenomation in Wistar rats treated with antivenom and the aqueous extract of the plant mikania glomerata. The animals were divided into three groups: Group C (control); Group VS-venom and antivenom; Group VSM-venom, antivenom and aqueous extract of M glomerata. Crotalic poison caused clinical and laboratory alterations in Wistar mice. Significant clinical alterations were: temperature decrease, edema in the venom inoculated member, sedation and a locomotion decrease in groups VS and VSM when compared with group C. A faster recovery from sedation was observed only for animals of group VSM when compared to VS. There was an increase in the number of leukocytes, neutrophils and creatine kinase in the VS and VSM groups, compared to group C. Wistar rats showed a high resistance to crotalic venom. Additional studies with different doses, time of treatment, different administration methods and histopathological and immunological studies are necessary to understand the action of M glomerata in crotalic accidents. Rev. Biol. Trop. 57 (4): 929-937. Epub 2009 December 01.

Influence of fertilizer on coumarin content and biomass production in Mikania glomerata sprengel

Mikania glomerata Sprengel leaf extracts have been used in cough syrup formulations due to the presence of active coumarin derivatives. Yields of such natural compounds in cultivated plants can be affected by several nutritional factors. To determine the effect of fertilization on biomass productivity, organ proportion and coumarin content, Mikania glomerata plants were submitted during one year to treatments with organic (humus or manure) and inorganic (different levels of nitrogen) fertilizers. Coumarin concentration was raised by organic fertilization, inorganic nutrients induced increased phytomass (stem and leaf) yield, however no fertilized plants showed enhanced leaf production.

Vegetative propagation of Mikania glomerata: Micro-propagation and cuttings

The scope of this work was to compare two systems for vegetative propagation: conventional one (from cut stems) and in vitro micropropagation from axillary buds. Nodal segments (1 cm) of Mikania glomerata were used as explants. The experiments were evaluated in relation to number of shoots; % of rooting; number of roots and total fresh weight. Multiple shoots developed in MS containing 0.5 mg/L BAP. Rooting was induced in the presence of 1.0 mg/L IBA. Stems with five buds and one pair of leaves were the most appropriate for the production of cuttings. The time necessary for developing a protocol for the production of M. glomerata micropropagated plantlets was 6 months, whereas only half time was required to produce plantlets from stem cuttings. The greatest problem met during micropropagation was the culture contamination by endophytic bacteria and fungi.

Coumarin production in Mikania glomerata callus

Cell cultures of Mikania glomerata Sprengel were established with leaf segments cultured on White medium supplemented with 1 mg/L BA and 3 mg/L NAA. Different types and concentrations of growth regulators were tested for callus maintenance. Determination of coumarin content was performed in HPLC using authentic coumarin standard. Growth regulator concentration affected biomass and coumarin accumulation. Cultures developed in semisolid medium containing both BA and NAA exhibited enhanced biomass production as well as coumarin accumulation. In the most favorable conditions tested, cells accumulated 25 μg/g of dry weight what is much inferior to the yield already reported in intact plants (5 mg/g of dry weight). However, results obtained so far suggest several alternatives for culture manipulation in order to optimize the productivity of coumarin by M. glomerata cultured cells.

Seasonal variation in coumarin content of Mikania glomerata

Mikania glomerata Spengal extract contains approximately 0.5 percent of coumarin, a substance that displays anti-inflammatory and expectoratory activities. Extracts from different young leaves of plants collected during the early evening of December and July contained the highest levels coumarin. Plants dried in oven with circulating air contained 7.3 mg of coumarin/g of dry weight, demonstrating that this was the most appropriate drying condition for Mikania glomerata.

Aspectos clínico, laboratorial e histopatológico da intoxicação experimental pelos venenos das serpentes Bothrops jararaca e Crotalus durissus terrificus em ratos Wistar tratados com antiveneno e Mikania glomerata

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Quantificação de citocinas na intoxicação experimental com veneno de Crotalus durissus terrificus e Bothropoides jararaca em ratos Wistar tratados com soroterapia e Mikania glomerata

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Quantificação de citocinas no soro e homogenato da pata na intoxicação experimental com veneno de Bothropoides jararaca em ratos Wistar tratados com soroterapia e Mikania glomerata

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Mikania glomerata Sprengel (Asteraceae) influences the mutagenicity induced by doxorubicin without altering liver lipid peroxidation or antioxidant levels

As shown in numerous studies, natural compounds may exert adverse effects, mainly when associated with some drugs. The hydroalcoholic extract of Mikania glomerata is the pharmaceutical form present in commercially available syrup used for the treatment of respiratory diseases in popular Brazilian medicine. The objective of the present investigation was (1) to evaluate the preventive effects of standardized hydroalcoholic extract of M. glomerata (MEx) against antitumoral drug doxorubicin (DXR)-induced micronucleated polychromatic erythrocytes (MNPCE) in a subchronic assay in mice, and (2) to determine the liver content of malondialdehyde (MDA) and the antioxidants glutathione (GSH) and vitamin E (VE). Male Swiss mice were treated for 30 d with MEx added to drinking water, combined or not with DXR (90 mg/kg body weight) injected intraperitoneally (ip) 24 h before analysis. The results demonstrated that MEx produced no genotoxic damage, but significantly increased the frequency of MNPCE induced by DXR, indicating a drug-drug interaction. This rise was not accompanied by lipid peroxidation or antioxidants level reduction, as measured by MDA, GSH, and VE. Despite the presence of coumarin (a known antioxidant), MEx may exert adverse effects probably in association with mutagenic compounds, although this effect on DNA damage did not involve oxidative stress.

Caracterização cromatográfica do extrato fluido de Mikania glomerata Sprengel.

Amostras de extrato fluido de guaco - Mikania glomerata Sprengel provenientes de drogas referentes aos 12 meses do ano, foram analisadas comparativamente com vistas a obtenção de perfil cromatográfico, ao lado de padrões de cumarina, ácido cinamoil grandiflórico e ácido caurenóico. Diversos sistemas cromatográficos foram empregados. Como fases estacionárias foram empregadas sílica gelG-GO e sílica gel GF; como fases móveis: heptano: acetona 10:30; benzeno: acetona: acetato de etila 15:3:2; benzeno: acetato de etila 19:1; clorofórmio; acetato de etila: 7:3 e como reveladoers: reativo sulfovanílico: anisaldeído; solução de hidróxido de sódio 5%. A observação dos cromatogramas foi feita à luz natural e à luz UV de 254 e 366 nm. Foram observadas as presenças de pelo menos 18 substâncias no extrato fluido entre as quais as usadas como padrão. O ácido caurenóico não aparece como mancha extinção quando observado à luz UV em camada de sílica gel GF. Revelado com reativo sulfovanílico inicialmente apresenta coloração amarela a qual passa a violeta, roxa e, finalmente branco-leitosa. O sistema cromatográfico que melhor se presta a caracterização do extrato de guaco e constituído de: fase móvel: sílica gel 60; fase estacionária: clorofórmio: acetato etila 7:3; revelador hidróxido de sódio a 5%. Neste sistema, após revelação e observação a luz UV, aparecem 5 manchas no extrato entre as quais a de maior intensidade e a correspondente a cumarina que apresenta coloração amarelo esverdeado.

Caracterização cromatográfica em camada delgada do extrato fluido de guaco: Mikania glomerata Sprengel.

As frações hexanicas, clorofórmicas, em acetato de etila e etanólica do extrato fluido de guaco - Mikania glomerata foram analisadas por cromatografia em camada delgada frente a padrões de ácido caurenóico, ácido cinamoilgrandiflorico, estigmasterol e cumarina visando o estabelecimento de perfil cromatográfico que permita identificar este insumo farmacêutico.

Anatomia foliar das espécies brasileiras de Mikania Willdenow seção Globosae Robinson: visão farmacognóstica.

O gênero Mikania Willdenow, criado em 1803, possui atualmente cerca de 300 espécies das quais 152 ocorrem no Brasil. São Paulo, Minas Gerais e Rio de Janeiro correspondem ao maior centro de dispersão. A maioria das espécies deste gênero possui emprego na medicina popular merecendo destaque as conhecidas pelo nome de guaco. Mikania hirsutissima DC e M. glomerata Sprengel constam da farmacopéia brasileira. Dentre as Mikanias Willdenow conhecidas por guaco merecem atenção as pertencentes a secção Globasae Robinson pelos usos que possuem na medicina popular e oficial. Este trabalho objetiva caracterizar microscopicamente as espécies brasileiras do gênero Mikania Willdenow Secção Globasae Robinson fornecendo subsídios a diagnose das drogas obtidas. Desenhos acompanham as descrições microscópicas e a chave artificial para a separação das espécies. A presença ou ausência nas folhas de camada celular aclorofilada subepidérmica separa as espécies da seção em 2 grupos de 4 espécies: 1) com característica: Mikania confertissima; M. laevigata; M. glomerata e M. hatschbachii; 2) sem característica: Mikania congesta; M. microlepsis; M. hookeriana; M. smilacina. Constitui características importantes na separação das espécies: número de camadas celulares do parênquima policádico; presença de braquiescléritos nas regiões parenquimática adjacente a feixes vasculares mais calibrosos; espessamento de paredes de células epidérmicas; presença de cutícula estriada; tipos de tricomas e de estomatos.

Co-cultivation of plant cells as a technique for the elicitation of secondary metabolite production

Cells of Mikania glomerata, Cephaelis ipecacuanha and Maytenus aquifolia were co-cultured in a two-phase system using filter paper as a solid support. The species were co-cultured in all possible paired combinations. Interaction between Mikania and Maytenus cells resulted in increased biomass production of Maytenus cells, but the friedelin content was reduced. Co-cultivation of Cephaelis and Mikania cells enhanced coumarin content, but inhibited the growth of Mikania cells. However, yield of emetine as well as Cephaelis biomass accumulation were positively stimulated by the co-cultivation. Results indicate a possible occurrence of allelopathy in such a system.

Ação de tinturas e óleos essenciais de plantas medicinais sobre o crestamento bacteriano comum do feijoeiro e na produção de proteínas de indução de resistência

A exploração da atividade biológica de compostos secundários presentes nas tinturas ou em óleos essenciais de plantas podem representar, ao lado da indução de resistência, mais uma forma potencial de controle de doenças em plantas cultivadas. O presente trabalho objetivou avaliar o potencial de tinturas de Lippia alba, Lippia sidoides, Mikania glomerata, Equisetum sp. e Hedera helix e óleos essenciais de Rosmarinus officinalis e Cinnamomum zeylanicum nas atividades in vitro, in vivo e na produção de proteínas na indução de resistência, em plantas de feijão vagem cultivar Bragança. Os resultados obtidos demonstraram que as tinturas de L. alba e L. sidoides e os óleos essenciais (R. officinalis e C. zeylanicum) apresentaram atividade in vitro aos isolados de Xanthomonas axonopodis pv. phaseoli. Todas as tinturas ensaiadas apresentaram menores valores do progresso da doença (AACPD), em relação à testemunha, merecendo destaque a tintura de L. alba, que estavam correlacionadas com os maiores teores de polifenoloxidase, peroxidase e proteínas solúveis totais, evidenciando uma possível indução de resistência. Os óleos essenciais não apresentaram diferença na AACPD e nem na indução de proteínas.