甲氧醉椒素是从卡瓦植物(Piper methysticum)中分离的内酯。卡瓦的活性成分是一组约。18种化合物统称为卡瓦内酯或卡瓦吡酮。卡瓦内酯、二氢卡瓦内酯、甲基卡瓦内酯、二氢甲基卡瓦内酯、甲氧醉椒素和去甲氧基醉椒素是6种主要的卡瓦内酯。卡瓦饮料和其他制剂被认为是抗焦虑的，用于治疗焦虑症。含有卡瓦灌木根的膳食补充剂已经涉及到几个人的肝脏毒性案例，包括几个在使用卡瓦补充剂后需要肝脏移植的人。
CB1
1.79 μM (IC 50 )
0.72 μM (Ki)
RelA
Yangonin is one of the six major kavalactones found in Piper methysticum .Yangonin potently inhibits NF-κB activation through suppression of the transcriptional activity of the RelA/p65 subunit of NF-κB. Yangonin significantly inhibits the induced expression of the NF-κB-reporter gene. However, Yangonin does not interfere with TNF-α-induced inhibitor of κBα (IκBα) degradation, p65 nuclear translocation, and DNA-binding activity of NF-κB. Yangonin inhibits not only the induced NF-κB activation by overexpression of RelA/p65, but also transactivation activity of RelA/p65. Yangonin does not inhibit TNF-α-induced activation of p38, but it significantly impairs activation of ERK 1/2 and stress-activated protein kinase/JNK.