Figure 6. TRPV1-linked signaling pathways mediating IL-6 and IL-8 release. TRPV1 stimulation leads to TAK1-dependent JNK1 and NF-κB activation. Activated JNK1 potentiates NF-κB activation by TAK1. NF-κB provides a positive feedback control of JNK1 phosphorylation through inhibition of DUSP1 expression, which is possibly controlled by PKCδ. Activated NF-κB translocates to nucleus, along with other transcription factors activated by p-JNK1 (e.g., AP-1) to promote IL-6 and IL-8 mRNA expression. Solid line indicates established interaction. Broken line represents unproven interaction. Arrowhead means stimulation whereas hammerhead represents inhibition. Arrow pointing from TAK1 to NF-κB is broken since it is not yet known if interaction is direct or there are signaling intermediates mediating NF-κB activation by TAK1.