Transient receptor potential ankyrin 1 (TRPA1) is a non-selective ion channel, which is expressed in nociceptor sensory neurons and transduces chemical, inflammatory, and neuropathic pain signals. Numerous non-reactive compounds and electrophilic compounds, such as endogenous inflammatory mediators and exogenous pungent chemicals, can activate TRPA1¹.

Ligustilide is a natural agonist of TRPA1 channels produced from the Umbelliferae plant Angelica sinensis with an effective concentration of 10-200 μM and an EC50 of 44 μM when binding to TRPA1. Ligustilide has a significant neuroprotective effect in transient forebrain ischemia and permanent cerebral focal ischemia. In a rat assay demonstrating ischemic damage, Ligustilide shortened mean escape time compared to the control group and prevented the effects caused by ligation of both common carotids. Ligustilide also increases choline acetyltransferase activity in ischemic brain tissues and might have therapeutic potential in the treatment of vascular-cerebral pathologies². Ligustilide also plays a role in the prevention of cell autophagy. In C2C12 cells, ligustilide causes a decrease in the production TNF-α induced autophagosomes³. Interestingly, Ligustilide can be found in various drugs used in traditional Chinese medicine such as Danzhi Xiaoyao San. This substance ameliorates depressive behavior via upregulation of serotonin production thus making Ligustilide a research candidate for psychological disorders⁴.