Anti-nociceptive Effect of 7-methoxy Coumarin from Eupatorium Triplinerve vahl (Asteraceae).

Abstract

Aim:To evaluate the anti-nociceptive activity of 7-methoxy coumarin isolated from ethyl acetate fraction of the alcoholic extract of Eupatorium triplinerve Vahl.Materials and Methods:The shade dried leaves of E. triplinerve were extracted with ethyl alcohol and the extract was condensed. This extract was fractionated with n-hexane, ethyl acetate, and n-butanol. The ethyl acetate fraction was subjected to column chromatography which yielded a crystalline compound-A, which was investigated for spectral characteristics.Pharmacological studies:The isolated compound-A was subjected to behavioral studies and anti-nociceptive evaluation in mice by acetic acid induced writhing and formalin induced nociception.Results:The spectral studies indicated that the structure of compound-A complies with 7- methoxy coumarin. Pre-treatment with 7-methoxy coumarin reduced the number of abdominal constrictions in mice and decreased the time spent in paw licking and biting response in formalin assay. There were no significant behavioral changes.Conclusion:A dose dependent anti-nociceptive action of 7- methoxy coumarin was revealed by the present experiments which support the traditional use of E. triplinerve in pain and inflammatory disorders.SUMMARY Bio-guided fractionation of alcoholic extract of E. triplinerve yielded 7-methoxy coumarin.7-methoxy coumarin was evaluated for its anti-nociceptive potential by acetic acid induced writhing and formalin induced nociception assays.7-methoxy coumarin exhibited significant inhibition of acetic acid induced writhing response and the second phase of formalin nociception.The anti-nociceptive action of 7-methoxy coumarin revealed by the present experiments supports the traditional use of E. triplinerve in pain and inflammatory disorders. Abbreviation used: TLC-Thin layer chromatography, Kg-kilogram, g-gram, TXB2-Thromboxane B2, UV-Ultraviolet, IgE-Immunoglobulin E, s.c-subcutaneous, p.o-oral route