A time limit for starting anti-inflammatory treatment for better improvement of olfactory dysfunction after head injury

• Project/Area Number: 26861369
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Otorhinolaryngology
• Research Institution: Mie University
• Principal Investigator: Kitano Masako 三重大学, 医学部附属病院, 助教 (20378334)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000); Fiscal Year 2016: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2015: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000); Fiscal Year 2014: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 鼻科学 / 嗅覚 / 再生医学

Outline of Final Research Achievements

The present study was designed to reveal the time limit for starting anti-inflammatory treatment for better improvement of traumatic olfactory dysfunction.
Olfactory nerve transection (NTx) was performed in OMP (olfactory marker protein)-tau-lacZ mice and subcutaneous injection of dexamethasone sodium phosphate (DXM) for consecutive 5 days was started at 7, 14, 28 and 42 days after the NTx (7, 14, 28 and 42-day interval). Histological assessment of nerve recovery in the olfactory bulb was made at 5, 14 and 42 days after the injury. Olfactory function assessments using both an olfactory avoidance behavioral test and evoked potential testing were also performed.
An anti-inflammatory treatment using steroids for traumatic olfactory dysfunction may be effective until 7 days but ineffective at 14 days or later after head injury.