ABSTRACT
Transient receptor potential ankyrin 1 (TRPA1) is a cation channel that plays a critical role in the occurrence and transmission of pain. By screening 393 marine invertebrate extracts for their antagonistic activity against TRPA1, it was found that the extract of the edible sea cucumber Bohadschia vitiensis had a remarkable potency. Bioassay-guided separation of the extract resulted in the isolation of six triterpene glycosides, including a novel analog. All six isolated compounds exhibited high inhibitory potency against TRPA1 (IC50 values ranging from 0.60 to 3.26 µM), which is comparable to that of a previously developed synthetic antagonist (A-967079). The discovery of TRPA1 antagonists, originated from this edible sea cucumber, opens the door for the elaboration of the valuable triterpene scaffold for the development of novel safe analgesics.