BACKGROUND: Activation of intravesical protease activated receptor 4 (PAR4) leads to release of urothelial macrophage migration inhibitory factor (MIF). MIF then binds to urothelial MIF receptors to release urothelial high mobility group box-1 (HMGB1) and elicit bladder hyperalgesia. Since MIF binds to multiple receptors, we investigated the contribution of individual urothelial MIF receptors to PAR4-induced HMGB1 release in vivo and in vitro and bladder pain in vivo.

METHODOLOGY/PRINCIPAL FINDINGS: We tested the effect of intravesical pre-treatment with individual MIF or MIF receptor (CD74, CXCR4, CXCR2) antagonists on PAR4-induced HMGB1 release in vivo (female C57/BL6 mice) and in vitro (primary human urothelial cells) and on PAR4-induced bladder hyperalgesia in vivo (mice). In mice, PAR4 induced HMGB1 release and bladder hyperalgesia through activation of intravesical MIF receptors, CD74 and CXCR4. CXCR2 was not involved in these effects. In primary urothelial cells, PAR4-induced HMGB1 release through activation of CD74 receptors. Micturition parameters in mice were not changed by any of the treatments.

CONCLUSIONS/SIGNIFICANCE: Urothelial MIF receptors CD74 and CXCR4 mediate bladder pain through release of urothelial HMGB1. This mechanism may set up persistent pain loops in the bladder and warrants further investigation. Urothelial CD74 and CXCR4 may provide novel targets for interrupting bladder pain.

Document Type


Publication Date


Notes/Citation Information

Published in PLOS ONE, v. 16, issue 8, 0255975.

This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

Digital Object Identifier (DOI)


Funding Information

PLV (DK121695) RB (AR049610) National Institutes of Health

journal.pone.0255975.s001.pdf (85 kB)
S1 Table. Awake micturition parameters. https://doi.org/10.1371/journal.pone.0255975.s001

journal.pone.0255975.s002.tif (6328 kB)
S1 Fig. Bladder pPCR: TNF-α, IL-1β. https://doi.org/10.1371/journal.pone.0255975.s002

journal.pone.0255975.s003.tif (6328 kB)
S2 Fig. Bladder protein: TNF-α, IL-1β. https://doi.org/10.1371/journal.pone.0255975.s003

journal.pone.0255975.s004.xlsx (55 kB)
S1 Dataset. Original datasets. https://doi.org/10.1371/journal.pone.0255975.s004