title: Maresin 1 Inhibits TRPV1 in Temporomandibular Joint-Related Trigeminal Nociceptive Neurons and TMJ Inflammation-Induced Synaptic Plasticity in the Trigeminal Nucleus.
abstract: In the trigeminal system, disruption of acute resolution processing may lead to uncontrolled inflammation and chronic pain associated with the temporomandibular joint (TMJ). Currently, there are no effective treatments for TMJ pain. Recently, it has been recognized that maresin 1, a newly identified macrophage-derived mediator of inflammation resolution, is a potent analgesic for somatic inflammatory pain without noticeable side effects in mice and a potent endogenous inhibitor of transient receptor potential vanilloid 1 (TRPV1) in the somatic system. However, the molecular mechanisms underlying the analgesic actions of maresin 1 on TMJ pain are unclear in the trigeminal system. Here, by performing TMJ injection of a retrograde labeling tracer DiI (a fluorescent dye), I showed that maresin 1 potently inhibits capsaicin-induced TRPV1 currents and neuronal activity via Gαi-coupled G-protein coupled receptors in DiI-labeled trigeminal nociceptive neurons. Further, maresin 1 blocked TRPV1 agonist-evoked increases in spontaneous excitatory postsynaptic current frequency and abolished TMJ inflammation-induced synaptic plasticity in the trigeminal nucleus. These results demonstrate the potent actions of maresin 1 in regulating TRPV1 in the trigeminal system. Thus, maresin 1 may serve as a novel endogenous inhibitor for treating TMJ-inflammatory pain in the orofacial region.
authors.affiliation: Department of Physiology, College of Medicine, Gachon University, Incheon 406-799, Republic of Korea.
authors.forename: Chul-Kyu
authors.initials: CK
authors.lastname: Park
mesh_terms: D000818:Animals; D004281:Docosahexaenoic Acids / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D062559:NAV1.8 Voltage-Gated Sodium Channel / Q000502:physiology; D009473:Neuronal Plasticity / Q000187:drug effects*; D009619:Nociceptors / Q000187:drug effects* / Q000502:physiology; D050916:TRPV Cation Channels / Q000037:antagonists & inhibitors* / Q000502:physiology; D013704:Temporomandibular Joint / Q000502:physiology*; D013705:Temporomandibular Joint Disorders / Q000503:physiopathology*; D014278:Trigeminal Nuclei / Q000187:drug effects* / Q000502:physiology
chemical_list: C535211:7,14-dihydroxydocosa-4,8,10,12,16,19-hexaenoic acid; D062559:NAV1.8 Voltage-Gated Sodium Channel; C568318:Scn10a protein, mouse; D050916:TRPV Cation Channels; C493921:TRPV1 protein, mouse; D004281:Docosahexaenoic Acids