The transient receptor potential vanilloid 1 (TRPV1) receptor is relevant to the perception of noxious stimuli and has been studied as a target for new analgesics. The goal of this study was to identify a novel TRPV1 antagonist isolated from the leaves of the medicinal plant Vernonia tweedieana Baker. Among the compounds isolated from a dichloromethane fraction, only α-spinasterol reduced the nociception and edema induced by capsaicin injection. α-Spinasterol was able to displace [3H]resiniferatoxin binding and diminish calcium influx mediated by capsaicin. Moreover, α-spinasterol demonstrated good oral absorption, producing antinociceptive responses to heat, but did not change the mechanical threshold of naive mice. In addition, it did not produce antinociceptive effects in mice pretreated with resiniferatoxin. α-Spinasterol did reduce edema, mechanical, and heat hyperalgesia elicited by complete Freund's adjuvant paw injection. Body temperature was not affected. In conclusion, α-spinasterol, isolated from the medicinal plant Vernonia tweedieana Baker, is a novel, efficacious, and safe antagonist of TRPV1 with antinociceptive effects.
See article at J Pharmacol Exp Ther 2012, 343:258–269.
- Copyright © 2012 by The American Society for Pharmacology and Experimental Therapeutics