Antiinflammatory and antinociceptive activities of Blechnum occidentale L. extract.
OBJECTIVE
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.


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 (0.01-100mg/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.


CONCLUSIONS
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.
Nonato
Fabiana Regina
FR
Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Rua Waldemar Falcão 121, CEP 40296-710 Salvador, Bahia, Brazil.
Barros
Tais Adelita Almeida
TA
Lucchese
Angélica Maria
AM
Oliveira
Carlos Eduardo Cordeiro
CE
dos Santos
Ricardo Ribeiro
RR
Soares
Milena Botelho Pereira
MB
Villarreal
Cristiane Flora
CF
D000700:Analgesics / Q000494:pharmacology* / Q000633:toxicity; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology* / Q000633:toxicity; D004305:Dose-Response Relationship, Drug; D029624:Ferns / Q000737:chemistry*; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology* / Q000633:toxicity; D051381:Rats; D017208:Rats, Wistar
D000700:Analgesics; D000893:Anti-Inflammatory Agents; D010936:Plant Extracts