PARTE UTILIZADA= Used part: Partes aéreas.

ACCION FARMACOLOGICA: Dolencias pulmonares, afecciones urinarias.

COMPOSICIÓN QUÍMICA= Pharmacological action: Aim of study: Blechnum occidentale L. is a terrestrial fern that ranges from the United States to South America, and is employed in Brazilian folk medicine. In the present study we investigated the antinociceptive and antiinflammatory activities of the methanolic extract of Blechnum occidentale L. (MEB) in animal models of pain and inflammation to support its medicinal use in treatment of inflammatory and pulmonary diseases, urinary infections and liver diseases. Materials and methods: The antinociceptive activity of MEB was evaluated using the writhing, formalin, and tail flick tests. The antiinflammatory activity of MEB was evaluated in carrageenan-induced paw oedema and neutrophil migration. In order to discard possible non-specific muscle relaxant or sedative effects of MEB, mice motor performance was evaluated in the rota rod test and its toxicity evaluated over 14 days. Results: Intraperitoneal (IP) administration of MEB (0.01-100 mg/kg) produced a dose-related antinociception on acetic acid-induced writhing in mice. Oral administration of MEB, at a different range of doses (100-400 mg/kg), also produced significant antinociceptive effect on the writhing test. Furthermore, treatment with MEB (100 and 200 mg/kg IP) inhibited significantly both the early and late phases of formalin-induced hypernociception in rats. In contrast, treatment with MEB (100 and 200 mg/kg IP) did not prevent the thermal nociception in the tail flick test. The IP administration of MEB (100 and 300 mg/kg) significantly reduced the paw oedema induced by carrageenan. Moreover, systemic treatment with MEB (11-300 mg/kg) reduced the neutrophil migration in the carrageenan-induced migration to the peritoneal cavity. In the rota rod test, MEB-treated mice did not show any significant motor performance alterations with the dose of 300 mg/kg. In addition, over the study duration of 14 days, there were no deaths or toxic signs recorded in the mice given 100 or 1000 mg/kg of MEB. Conclusion: The results described here are the first report of pharmacological studies of Blechnum occidentale L. and indicate that this plant has antinociceptive and antiinflammatory activities which support its folk medicine use. © 2009 Elsevier Ireland Ltd. All rights reserved.

ZONA GEOGRAFICA= Geografical zone: América. 

DIVERSIDAD GENÉTICA Y MEJORAMIENTO DE PLANTAS MEDICINALES= Medicinal plants and improvement of medicinal herbs:

During surveys in 2003-2004 conducted in glasshouses in the Main Botanical Garden of the Russian Academy of Sciences several fern plants infected by the strawberry crimp nematode, Aphelenchoides fragariae, were found. The infected ferns belong to the following species: Aneimia rotundifolia, Blechnum occidentale, B. gibbum, Pteris longifolia, P. cretica cv. wimsetti, P. cretica and Stenochlaena tenuifolia. Nematode infection produced water-soaked bands that become dark brown to black, usually between the leaf veins. Several plants of Sambucus racemosa attacked by the chrysanthemum foliar nematode A. ritzemabosi were found in an outdoor area near the glasshouses. Nematodes were extracted from the leaves and growing points of S. racemosa. Morphological and morphometrical diagnostic characters and descriptions are given for A. fragariae and A. ritzemabosi. Differences in the 18S rRNA gene sequences allow a clear separation of these species from each other and from other Aphelenchoides species. The phylogenetic relationships of these species with other aphelenchids as inferred from analysis of the 18S-rRNA gene are presented and discussed.

1) TOURSARKISSIAN, Martín. Plantas medicinales de Argentina : sus nombres botánicos, vulgares, usos y distribución geográfica. Buenos Aires : Hemisferio Sur, 1980,p.103.

2) NONATO, F.R., et al. Antiinflammatory and antinociceptive activities of Blechnum occidentale L. extract. Journal of Ethnopharmacology. 2009, vol.125, nº1, p.102-107.

3) CHIZHOV, V.N., et al. Morphological and molecular characterization of foliar nematodes of the genus Aphelenchoides: A. fragariae and A. ritzemabosi (Nematoda: Aphelenchoididae) from the Main Botanical Garden of the Russian Academy of Sciences, Moscow. Russian Journal of Nematology. 2006, vol.14, nº2, p.179-184.