• Yuka Harada, Jing Zhang, Kazuhisa Imari, Ryo Yamasaki, Junjun Ni, Zhou Wu, Kenji Yamamoto, Jun-Ichi Kira, Hiroshi Nakanishi, and Yoshinori Hayashi.
• Department of Aging Science and Pharmacology, Faculty of Dental Science, Kyushu University, Fukuoka, Japan. Dr. Hayashi is now with the Department of Physiology, Nihon University School of Dentistry, Tokyo, Japan.
• Pain. 2019 Sep 1; 160 (9): 2050-2062.

AbstractPain is a frequent and disabling symptom in patients with multiple sclerosis (MS); however, the underlying mechanisms of MS-related pain are not fully understood. Here, we demonstrated that cathepsin E (CatE) in neutrophils contributes to the generation of mechanical allodynia in experimental autoimmune encephalomyelitis, an animal model of MS. We showed that CatE-deficient (CatE) mice were highly resistant to myelin oligodendrocyte glycoprotein (MOG35-55)-induced mechanical allodynia. After MOG35-55 immunization, neutrophils immediately accumulated in the dorsal root ganglion (DRG). Adoptive transfer of MOG35-55-stimulated wild-type neutrophils into the dorsal root ganglion induced mechanical allodynia in the recipient C57BL/6 mice. However, the pain threshold did not change when MOG35-55-stimulated CatE neutrophils were transferred into the recipient C57BL/6 mice. MOG35-55 stimulation caused CatE-dependent secretion of elastase in neutrophils. Behavioral analyses revealed that sivelestat, a selective neutrophil elastase inhibitor, suppressed mechanical allodynia induced by adoptively transferred MOG35-55-stimulated neutrophils. MOG35-55 directly bound to toll-like receptor 4, which led to increased production of CatE in neutrophils. Our findings suggest that inhibition of CatE-dependent elastase production in neutrophil might be a potential therapeutic target for pain in patients with MS.

24 keywords...

hide…