CCR2 upregulation in DRG neurons plays a crucial role in gastric hyperalgesia associated with diabetic gastropathy.

Abstract

Background Diabetic gastropathy is a complex neuromuscular dysfunction of the stomach that commonly occurs in diabetes mellitus. Diabetic patients often present with upper gastrointestinal symptoms, such as epigastric discomfort or pain. The aim of this study was to assess gastric sensation in streptozocin-induced diabetes mellitus (DM) rats and to determine the contribution of C-C motif chemokine receptor 2 (CCR2) signaling to gastric hyperalgesia. Results DM rats showed signs of neuropathy (cutaneous mechanical hyperalgesia) from two weeks after streptozocin administration until the end of the experiment. Accelerated solid gastric emptying was observed at two weeks after streptozocin administration compared to the controls. Intense gastric hyperalgesia also developed in DM rats at two weeks after streptozocin administration, which was significantly reduced after intrathecal administration of the CCR2 antagonist INCB3344. Immunochemical analysis indicated that CCR2 expression was substantially upregulated in small and medium-sized dorsal root ganglia neurons of DM rats, although the protein level of monocyte chemoattractant protein-1, the preferred ligand for CCR2, was not significantly different between the control and DM groups. Conclusions These data suggest that CCR2 activation in nociceptive dorsal root ganglia neurons plays a role in the pathogenesis of gastric hyperalgesia associated with diabetic gastropathy and that CCR2 antagonist may be a promising treatment for therapeutic intervention.

• Authors: Aye Aye-Mon, Kiyomi Hori, Yu Kozakai, Tatsuki Nakagawa, Shinichiro Hiraga, Tsuneo Nakamura, Yoshitake Shiraishi, Hiroaki Okuda, Noriyuki Ozaki
• Journal: Molecular pain (Mol Pain) 2018 Jan-Dec Vol. 14 Pg. 1744806917751322 ISSN: 1744-8069 [Electronic] United States
• PMID: 29359616 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Blood Glucose
• Ccr2 protein, rat
• Chemokine CCL2
• Receptors, CCR2
• Streptozocin

Topics

• Animals
• Blood Glucose (metabolism)
• Chemokine CCL2 (metabolism)
• Diabetes Mellitus, Experimental (blood, complications, pathology, physiopathology)
• Diabetic Neuropathies (blood, metabolism, pathology)
• Ganglia, Spinal (metabolism, pathology)
• Hyperalgesia (blood, complications, pathology, physiopathology)
• Male
• Motor Activity
• Rats, Sprague-Dawley
• Receptors, CCR2 (antagonists & inhibitors, metabolism)
• Spinal Cord (metabolism, pathology)
• Stomach (pathology, physiopathology)
• Stomach Diseases (complications, metabolism, pathology, physiopathology)
• Streptozocin
• Up-Regulation