University Of Tasmania

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Involvement of macrophages and spinal microglia in osteoarthritis pain

journal contribution
posted on 2023-05-21, 00:03 authored by Pan, T-T, Feng PanFeng Pan, Gao, W, Hu, S-s, Wang, D

Purpose of Review: Chronic pain in osteoarthritis (OA) is characterized by pain sensitization, which involves both peripheral and central mechanisms. Studies suggest synovial macrophage and spinal microglia are implicated in pain sensitization in OA. We, therefore, reviewed the evidence of whether synovial macrophage and spinal microglia facilitated pain sensitization at diverse levels and how this event occurred in OA.

Recent Findings: Peripherally, joint inflammation is now believed to be a source of OA-related pain. Synovial macrophages accumulate in OA inflamed synovium and display a pro-inflammatory phenotype. Abundant macrophage-derived pro-inflammatory cytokines and other pain-causing substance facilitate hyperexcitation of primary sensory neuron in OA-related pain. Thus, activated synovial macrophage was considered a predictor for phenotyping of OA pain clinically. In response to affected joint-derived strong nociception, aberrant neuronal excitability is often associated with the hyperactivity of microglia in the spinal dorsal horn, thereby leading to central sensitization.

Summary: Hyperactivity of synovial macrophage and spinal microglia underlies the mechanisms of pain sensitization at the peripheral and central level in OA. This concept provides not only a clinically relevant strategy for identifying the phenotype of OA-related pain but also has the potential to develop individualized interventions for OA, particularly in those patients with hyperactivity of macrophage and microglia.


Publication title

Current Rheumatology Reports










Menzies Institute for Medical Research


Current Science

Place of publication

United States

Rights statement

Copyright The Author(s), under exclusive licence to Springer Science+Business Media, LLC part of Springer Nature 2021

Repository Status

  • Restricted

Socio-economic Objectives

Human pain management; Treatment of human diseases and conditions; Determinants of health