One other thought OP, I've worked with Grape Seed Extract for over 25 yrs and did a search with Grape Seed Ex and TN and did get some hits. Here is one. There can be so many supplements out there that we don't know about. And Grape Seed Ex in my life has been short of a miracle. I don't know where my life would be without it, but won't even wander there.

Dietary grape seed polyphenols repress neuron and glia activation in trigeminal ganglion and trigeminal nucleus caudalis