Format

Send to

Choose Destination
J Clin Invest. 2018 Aug 1;128(8):3568-3582. doi: 10.1172/JCI99888. Epub 2018 Jul 16.

GPR37 regulates macrophage phagocytosis and resolution of inflammatory pain.

Author information

1
Department of Anesthesiology, Duke University Medical Center, Durham, North Carolina, USA.
2
Department of Physiology, Center of Neuroscience, Key Laboratory of Medical Neurobiology of the Ministry of Health of China, Zhejiang University School of Medicine, Hangzhou, China.
3
Department of Neurobiology, Duke University Medical Center, Durham, North Carolina, USA.

Abstract

The mechanisms of pain induction by inflammation have been extensively studied. However, the mechanisms of pain resolution are not fully understood. Here, we report that GPR37, expressed by macrophages (MΦs) but not microglia, contributes to the resolution of inflammatory pain. Neuroprotectin D1 (NPD1) and prosaptide TX14 increase intracellular Ca2+ (iCa2+) levels in GPR37-transfected HEK293 cells. NPD1 and TX14 also bind to GPR37 and cause GPR37-dependent iCa2+ increases in peritoneal MΦs. Activation of GPR37 by NPD1 and TX14 triggers MΦ phagocytosis of zymosan particles via calcium signaling. Hind paw injection of pH-sensitive zymosan particles not only induces inflammatory pain and infiltration of neutrophils and MΦs, but also causes GPR37 upregulation in MΦs, phagocytosis of zymosan particles and neutrophils by MΦs in inflamed paws, and resolution of inflammatory pain in WT mice. Mice lacking Gpr37 display deficits in MΦ phagocytic activity and delayed resolution of inflammatory pain. Gpr37-deficient MΦs also show dysregulations of proinflammatory and antiinflammatory cytokines. MΦ depletion delays the resolution of inflammatory pain. Adoptive transfer of WT but not Gpr37-deficient MΦs promotes the resolution of inflammatory pain. Our findings reveal a previously unrecognized role of GPR37 in regulating MΦ phagocytosis and inflammatory pain resolution.

KEYWORDS:

G-protein coupled receptors; Inflammation; Macrophages; Neuroscience; Pain

Supplemental Content

Full text links

Icon for American Society for Clinical Investigation Icon for PubMed Central
Loading ...
Support Center