Pinosylvin Inhibits TRPA 1‐Induced Calcium Influx In Vitro and TRPA 1‐Mediated Acute Paw Inflammation In Vivo

Pinosylvin (3,5-dihydroxy-trans-stilbene) is a stilbenoid polyphenol structurally related to resveratrol, and it is found in heartwood, knot and bark of Pinus species.Pinosylvin has been shown to possess anti-inflammatory and cancer-chemopreventive properties as well as being an antioxidant preventing oxidative stress [1][2][3][4].Transient receptor potential ankyrin 1 (TRPA1) is an ion channel expressed in the terminal ends of sensory neurons throughout the body.It functions as a chemosensor for potentially harmful environmental substances, and it is also involved in pathophysiological conditions such as pain, hyperalgesia and inflammation [5][6][7][8].Curiously, pharmacological inhibition of TRPA1 has shown positive results in animal models of inflammatory diseases such as asthma [9], colitis [10] and gout [11,12].However, rather few compounds are known to antagonize TRPA1: there is a clear need for new substances with the ability to block this ion channel.Interestingly, resveratrol has shown putative activity as a TRPA1 antagonist [13].Therefore, we were interested in studying the effect of pinosylvin on TRPA1 in vitro by measuring TRPA1mediated Ca 2+ influx and membrane currents, and by investigating in vivo the effect of pinosylvin on TRPA1-induced acute inflammation.