Targeting Toll-like Receptor-4 (TLR4)-an Emerging Therapeutic Target for Persistent Pain States

Overview

Journal Pain

Specialties Neurology
Psychiatry

Date 2018 Jun 12

PMID 29889119

Citations 62

Authors

Kelly Bruno

Sarah A Woller

Yury I Miller

Tony L Yaksh

Mark Wallace

Graham Beaton

Krishnan Chakravarthy

Affiliations

Soon will be listed here.

Abstract

Toll-like receptors (TLRs) are a family of pattern recognition receptors that initiate signaling in innate and adaptive immune pathways. The highly conserved family of transmembrane proteins comprises an extracellular domain that recognizes exogenous and endogenous danger molecules and an ectodomain that activates downstream pathways in response. Recent studies suggest that continuous activation or dysregulation of TLR signaling may contribute to chronic disease states. The receptor is located not only on inflammatory cells (meningeal and peripheral macrophages) but on neuraxial glia (microglia and astrocytes), Schwann cells, fibroblasts, dorsal root ganglia, and dorsal horn neurons. Procedures blocking TLR functionality have shown pronounced effects on pain behavior otherwise observed in models of chronic inflammation and nerve injury. This review addresses the role of TLR4 as an emerging therapeutic target for the evolution of persistent pain and its role in noncanonical signaling, mediating anomalous pro-algesic actions of opiates. Accordingly, molecules targeting inhibition of this receptor have promise as disease-modifying and opioid-sparing alternatives for persistent pain states.

Citing Articles

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