Isolation of compound and CNS depressant activities of Mikania scandens Willd with special emphasis to brain biogenic amines in mice.

Mikania scandens, a twining herb that grows as a weed in India and Bangladesh is used as vegetables and is a good source of vitamin A, C, B complex, mikanin, sesquiterpenes, betasitosterin, stigmasterol and friedelin. The present communication reports CNS depressant activities with special emphasis to brain biogenic amines in mice. Ethanol extract of leaves of M. scandens (EEMS) was prepared by Soxhalation and analyzed chemically. EEMS potentiated sleeping time induced by pentobarbitone, diazepam and meprobamate and showed significant reduction in the number of writhes and stretches. EEMS caused significant protection against pentylene tetrazole-induced convulsion and increased catecholamines and brain amino acids level significantly. Results showed that EEMS produced good CNS depressant effects in mice.

Kaurene diterpene induces apoptosis in U87 human malignant glioblastoma cells by suppression of anti-apoptotic signals and activation of cysteine proteases

Gliomas are the most common and malignant primary brain tumors in humans. Studies have shown that classes of kaurene diterpene have anti-tumor activity related to their ability to induce apoptosis. We investigated the response of the human glioblastoma cell line U87 to treatment with ent-kaur-16-en-19-oic acid (kaurenoic acid, KA). We analyzed cell survival and the induction of apoptosis using flow cytometry and annexin V staining. Additionally, the expression of anti-apoptotic (c-FLIP and miR-21) and apoptotic (Fas, caspase-3 and caspase-8) genes was analyzed by relative quantification (real-time PCR) of mRNA levels in U87 cells that were either untreated or treated with KA (30, 50, or 70 µM) for 24, 48, and 72 h. U87 cells treated with KA demonstrated reduced viability, and an increase in annexin V- and annexin V/PI-positive cells was observed. The percentage of apoptotic cells was 9% for control cells, 26% for cells submitted to 48 h of treatment with 50 µM KA, and 31% for cells submitted to 48 h of treatment with 70 µM KA. Similarly, in U87 cells treated with KA for 48 h, we observed an increase in the expression of apoptotic genes (caspase-8, -3) and a decrease in the expression of anti-apoptotic genes (miR-21 and c-FLIP). KA possesses several interesting properties and induces apoptosis through a unique mechanism. Further experiments will be necessary to determine if KA may be used as a lead compound for the development of new chemotherapeutic drugs for the treatment of primary brain tumors.

Effects of a Mikania laevigata extract on bone resorption and RANKL expression during experimental periodontitis in rats

OBJECTIVES: The Mikania laevigata extract (MLE) (popularly known in Brazil as "guaco") possesses anti-inflammatory properties. In the present study we tested the effects of MLE in a periodontitis experimental model in rats. We also investigated possible mechanisms underlying such effects. MATERIAL AND METHODS: Periodontal disease was induced by a ligature placed around the mandibular first molars of each animal. Male Wistar rats were divided into 4 groups: non-ligated animals treated with vehicle; non-ligated animals treated with MLE (10 mg/kg, daily); ligature-induced animals treated with vehicle and ligature-induced animals treated with MLE (10 mg/kg, daily). Thirty days after the induction of periodontal disease, the animals were euthanized and mandibles and gingival tissues removed for further analysis. RESULTS: Morphometric analysis of alveolar bone loss demonstrated that MLE-treated animals presented a decreased alveolar bone loss and a lower expression of the activator of nuclear factor-κB ligand (RANKL) measured by immunohistochemistry. Moreover, gingival tissues from the MLE-treated group showed decreased neutrophil migration myeloperoxidase (MPO) assay. CONCLUSIONS: These results indicate that MLE may be useful to control bone resorption during progression of experimental periodontitis in rats.

Farmacobotânica, fitoquímica e farmacologia do Guaco: revisão considerando Mikania glomerata Sprengel e Mikania laevigata Schulyz Bip. ex Baker / Morpho-anatomy, phytochemistry and pharmacology of Mikania glomerata Sprengel: a brief literature review

As plantas medicinais vêm sendo cada vez mais utilizadas devido às suas propriedades preventivas, paleativas e curativas, além de ser uma terapia alternativa que traz inúmeros benefícios aos usuários. As espécies Mikania glomerata e M. laevigata pertencem à família Asteraceae e são popularmente conhecidas como guaco sendo utilizadas no tratamento de enfermidades do trato respiratório. Além disso, as duas espécies são frequentemente confundidas ou citadas na literatura de forma errada. O presente trabalho teve por objetivo realizar uma revisão bibliográfica sobre a farmacologia, farmacobotânica e fitoquímica dos metabólitos secundários de Guaco, tendo destaque a cumarina, a biossíntese e as ações biológicas. As ações broncodilatadora, expectorante, anti-inflamatória e antialérgica, além de interações com alguns antibióticos e anticoagulantes, também foram descritas neste estudo.

Medicinal plants have been increasingly used due to their preventive, palliative and curative properties, besides being an alternative therapy that brings a large number of benefits to their users. The species Mikania glomerata belongs to the Asteraceae family and is popularly known as guaco, being employed to treat diseases of the respiratory tract. This study aimed to carry out a literature review about the pharmacology, pharmacobotany and phytochemistry of the secondary metabolites of M. glomerata, particularly coumarin, its biosynthesis and biological actions. The bronchodilator, expectorant, anti-inflammatory and antiallergic actions, as well as the interactions with some antibiotics and anticoagulants, were also described in this study.

Antiproliferative and genotoxic effects of Mikania glomerata (Asteraceae)

Mikania glomerata is a plant used in Brazilian traditional medicine, known as 'guaco'. It possesses anti-inflammatory properties and the aqueous extracts of its leaves are indicated for the treatment of diseases of the respiratory tract. This study aimed at evaluating the antiproliferative and genotoxic effect of Mikania glomerata leaf infusions on the cell cycle of onion. The material used was collected in the native environment from Rio Grande do Sul State, Brazil. Aqueous extracts through infusions were prepared in two concentrations: 4g/L (usual concentration) and 16g/L (4x more concentrated) of each of the populations. Two groups of four onion bulbs for each plant population were used plus a control group. The rootlets were fixed in ethanol-acetic acid (3:1), conserved in ethanol 70% and slides were prepared using the squashing technique colored with orcein 2%. The cells were observed and analyzed during cell cycle. Per group of bulbs, 2000 cells were analyzed, and the mean values of the cell number of each of the phases of the cell cycle were calculated, determining the mitotic index (MI). Statistic analyses of the data were carried out by the x2 ( p= 0.05) test. We conclude that M. glomerata presents both antiproliferative and genotoxic activity.

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 linical 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.

El envenamiento crotálico representa el número más alto de muertes cuando es comparado con envenenamientos por mordeduras de otras serpientes de interés médico. El veneno crotálico tiene importantes características de acción neurotóxica, miotoxicidad, nefrotoxicidad, coagulación y acción hemolítica. Este trabajo evaluó los aspectos clínicos y de laboratorio del envenenamiento experimental con el veneno de la serpiente Crotalus durissus terrificus en las ratas Wistar tratadas con suero antiofídico y extracto acuoso de M. glomerata. Los animales fueron separados en tres diferentes grupos: grupo control (C); grupo veneno+suero (VS), grupo veneno+suero+extracto acuoso de M. glomerata (VSM). El veneno crotálico causó alteraciones clínicas y diferencias en los análisis sanguíneos practicados a los ratones Wistar evaluados. Las alteraciones clínicas más importantes fueron una disminución de la temperatura, edema en el miembro inoculado de veneno, la sedación y una disminución de la locomoción en los grupos VS y VSM comparado con el grupo C. Una rápida recuperación de la sedación estadísticamente significativa fue observada en los animales del grupo VSM al compararse con los del grupo VS. Los análisis sanguíneos mostraron un aumento en el número de leucocitos, neutrofilos y creatina quinasa en los grupos VS y VSM comparados con el grupo C. Los ratones Wistar mostraron una alta resistencia al veneno del crótalo. Estudios adicionales con variación en las dosis, tiempo de tratamiento, y métodos de administración, así como la realización de estudios histopatológicos e inmunológicos son importantes para comprender la acción de M. glomerata en accidentes crotálicos.

Isolation of syringaldehyde from Mikania laevigata medicinal extract and its influence on the fatty acid profile of mice / Extrato medicinal de Mikania laevigata: influência no perfil de ácidos graxos em camundongos e isolamento de siringaldeído por CLAE semipreparativa

The Mikania genus is widely known as "guaco" and is used to treat fever, rheumatism, flu and respiratory diseases. Our previous work evidenced the synergism among M. laevigata extract components to produce desirable effects, and included the coumarin precursor, o-coumaric acid as marker. Many Mikania species are producers of ent-kaurene diterpenes which presented antiespasmodic and relaxant activities on smooth muscle. Seeking to standardize the guaco extract, which is registered in the Brazilian Pharmacopoea, this paper deals with the determination of kaurenoic acid through LC-PDA and the isolation through LC of syringaldehyde. Kaurenoic acid was not found in the extract, and syringaldehyde is one of the major compounds of pharmacopoeal extract, together with coumarin and o-coumaric acid. Samples from the lung and liver of Balb-C isogenic allergic pneumonitis bearing mice, treated with the same extract, were analyzed through GC-FID, and the fatty acid content was determined and analyzed. The results obtained by measuring the arachidonic acid (ARA) and docosahexaenoic acid (DHA) in the liver and lung of treated animals demonstrated that the fatty acid composition is distinct in both tissues, and that in the liver, only the DHA was altered as a result of the treatments. DHA is absent in the lung and in both organs, no significant difference in ARA production was observed. The aqueous extract, coumarin and o-coumaric acid stimulated DHA synthesis in the liver (p < 0.05).

O gênero Mikania é popularmente conhecido como "guaco" e é utilizado para tratar febre, reumatismo, resfriados e afecções respiratórias. Em trabalho prévio demonstramos sinergismo entre os componentes do extrato de M. laevigata para produzir os efeitos farmacológicos esperados, incluindo a cumarina e seu precursor ácido o-cumárico como marcadores. Muitas espécies de Mikania são produtoras de diterpenos ent-caurenos que apresentam atividade antispasmódica e relaxante da musculatura lisa. Buscando a padronização do extrato medicinal de guaco (preparado segundo a farmacopéia brasileira 1ª edição), este trabalho visou determinar a presença de ácido caurenóico através de CLAE-DAD e isolou siringaldeído através de CLAE semipreparativa, sendo que o primeiro não foi encontrado no extrato e o siringaldeído é um dos seus componentes majoritários. Camundongos isogênicos Balb-C portadores de pneumonite alérgica foram tratados com este extrato, e amostras de pulmão e fígado foram analisadas por CG-DIC quanto ao seu conteúdo de ácidos graxos. A quantidade de ácido araquidônico (ARA) e de ácido docosahexaenóico (DHA) encontrada demonstrou que a composição é distinta em ambos tecidos, e apenas a concentração de DHA hepático foi alterado em função do tratamento, o qual não foi encontrado no pulmão. Não foi detectada diferença significativa na produção de ARA. Tanto o extrato aquoso, quanto a cumarina e o ácido o-cumárico, estimularam a síntese de DHA no fígado (p < 0.05).