Chronic muscle pain pathophysiology from the viewpoint of mitochondria dysfunction

• Project/Area Number: 16K15801
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Prosthodontics/ Dental materials science and
• Research Institution: Okayama University
• Principal Investigator: MAEKAWA KENJI 岡山大学, 医歯薬学総合研究科, 准教授 (20304313)
• Co-Investigator(Kenkyū-buntansha): 大野 充昭 岡山大学, 医歯薬学総合研究科, 助教 (60613156) ; 水口 一 岡山大学, 大学病院, 講師 (30325097) ; 窪木 拓男 岡山大学, 医歯薬学総合研究科, 教授 (00225195)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000); Fiscal Year 2017: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000); Fiscal Year 2016: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 慢性筋痛 / 疾患感受性 / ビタミンD / 受容体 / ミトコンドリア / コエンザイムQ10

Outline of Final Research Achievements

We made an attempt to elucidate the relationship between vitamin D function and muscle pain. This hypothesis was established based on the several previous reports, which describe the positive relationship between taking antilipemic and muscle pain onset, especially seen in hyperlipidemia patients with vitamin D deficiency.
As the results, gene expression levels of vitamin D receptor was significantly higher in trapezius and masseter muscles, which are easily affected by muscle pain than limb muscles, which are not very sensitive to muscle pain. These results suggest the possible relationship between vitamin D function and muscle pain. In addition, expression levels of positive cell number of pain sensitivity marker (c-fos) in central nervous system under noxious stimulus application in masseter muscle tended to be higher in vitamin D deficiency rats than those in rats without vitamin D deficiency.