“What’s an immune-modulating herb anyway?” This question comes up a lot! So what is it? It’s an herbal action we lean on constantly in our materia medica, so let me tell you how I actually think about it. Your immune system is making decisions all day long, figuring out how hard to respond, how long to stay on the case, and when to stand down and start cleaning up. A modulating herb gets a say in those decisions instead of just cranking everything up, because it’s talking to the part of you that makes the call. That’s why the same plant can settle a response that’s running too hot in one person while supporting one that’s dragging in another. It works by speaking your immune system’s own language right there at the receptor! So next time you hear “immune-modulating,” think “this works with your immune system’s own judgment.” What’s your go-to immunomodulating herb?

Quick one for you all, and I want to hear your thinking before I drop the full picture. If you’ve spent any time with lymphatic herbs, you’ve noticed cleavers, calendula, and echinacea keep appearing. Then you find them again in the immune category. Most explanations just say “it gets things moving,” which is a description with zero context. So, here’s my question: do you think these are two separate mechanisms that happen to live in the same plants, or do you think lymphatic actions and immune actions aren’t actually that separate to begin with?

I've seen this done in other communities and thought it would be fun to try here! Let's go through the alphabet listing herbs, but with a twist: Latin binomials only. I'll start: A — Althaea officinalis Who's next?

Last week we walked through the wiring, and this week I want to follow the signal that actually moves through it, because the second you see how neurons talk to each other, every nervine herb you've ever heard of starts to click into place. Your central nervous system runs on a balance between two main neurotransmitters: glutamate is excitatory, so it tells neurons to fire, and GABA (gamma-aminobutyric acid) is inhibitory, so it tells them to quiet down. Here's how that quieting actually happens: a GABA molecule docks onto a GABA-A receptor sitting on the surface of a neuron, and the receptor opens a tiny channel that lets chloride ions flow into the cell. Chloride carries a negative charge, so as it rushes in, the inside of the neuron becomes more negative, and a more negative neuron is a much harder one to fire. So inhibition, at the molecular level, is really just a story about chloride. The GABA-A receptor also has a few side doors, which are separate spots on the receptor where other molecules can attach and turn the volume up or down on GABA's signal. The most well-known side door is the benzodiazepine site, which is exactly where pharmaceuticals like Xanax and Valium dock to amplify GABA's effect. Passionflower at the GABA-A Receptor Passionflower (Passiflora incarnata) was one of the first plants studied for activity at this receptor. When researchers started trying to figure out what in passionflower was producing its calming effects, one of the first compounds they isolated was chrysin, a flavonoid (a class of plant compounds you've seen come up across a lot of nervines and adaptogens). Chrysin is actually more concentrated in propolis and honey than in passionflower itself, but it was the passionflower research that put it on the map: Medina et al. (1990) showed it acted as a benzodiazepine-site ligand with anticonvulsant activity in animal models, and Brown et al. (2007) followed up by showing anxiolytic behavior in rats given chrysin specifically. Then Appel et al. (2011) added another layer when a standardized passionflower extract was shown to also slow GABA reuptake at the synapse, which is a completely separate mechanism from binding the receptor.

Don’t forget to check out Lesson 1 of The Nervous System Course in the Classroom! 📚🧠 If you’ve done through it - what something this lesson has taught you?