長期單側鼻阻塞對顱顏骨與嗅覺神經發育之影響—以冷光標定基質金屬蛋白酶-3基因啟動子之基因轉殖大鼠為模型

Abstract

鼻塞在發育階段對呼吸系統和顱顏顎骨形態產生了相當大的生理影響。本研究使用Mmp-3-luc基因轉殖大鼠進行活體冷光影像追踪，在單側鼻塞後長期觀察大鼠鼻部區域的表達。通過顯微斷層掃描檢查和三維圖像處理，計算對顱面部、鼻部和鼻竇區域的骨骼變化進行了測量和分析。還通過免疫組織化學（IHC）檢查了基質金屬蛋白酶-3和嗅覺標記蛋白的表達情況。實驗結果顯示單側鼻塞顯著降低了Mmp-3-luc轉基因大鼠鼻部區域的Mmp-3信號；而此訊號主要表達在呼吸上皮中。長期阻塞還導致了顱面部骨組織的形態學變化，如鼻中膈偏移、較長的上下顎間距和增加的上顎臼齒齒槽高度。免疫組織化學結果證實，它還導致了嗅覺神經束和嗅覺上皮的代償性生長。我們也利用Mmp-3-luc基因轉殖大鼠鼻黏膜上皮細胞之初代培養來測試培養基流動形成之剪力對nasoepithelial cell的影響，經由免疫螢光染色發現主要Luciferase之陽性染色在類似間質細胞樣態的細胞群而非末端分化上皮細胞樣態中。 在我們的研究中，長期的單側鼻塞導致鼻中膈向未受阻力的一側偏移，上顎臼齒高度發育變化，並減少了呼吸上皮中MMP-3的產生。然而，詳細的機制仍需要進一步的研究來探究。

Nasal obstruction exerts considerable physiological effects on the respiratory system and craniofacial morphology during the developmental stage. In this study, the author used Mmp-3-luc transgenic rats for in vivo tracking of long-term expression of Mmp-3 mRNA in the rat nasal region after unilateral nasal obstruction. Skeletal changes of the craniofacial, nasal, and sinus regions were measured and calculated through micro-computed tomography examination and analysis with 3D image processing software. Matrix metalloproteinase-3 and olfactory marker protein expressions were also investigated through immunohistochemistry (IHC) staining. In the result, unilateral nasal obstruction significantly reduced the MMP-3 signal in the nasal region of Mmp-3-luc transgenic rats, which was mainly expressed in the respiratory epithelium. Long-term obstruction also caused morphological changes of the craniofacial hard tissue, such as nasal septal deviation, longer inter-jaw distance, and increased maxillary molar dental height. It also caused compensatory growth in olfactory nerve bundles and the olfactory epithelium, as confirmed by IHC. In our study, long-term unilateral nasal obstruction caused nasal septal deviation toward the unobstructed side, hyperdivergent facial development including longer molar dental height, and reduced MMP-3 production. For the in-vitro experiment, luciferase staining through immunofluorescence showed positive staining after shear stress flow experiment. However, further investigation is necessary to explore the mechanism in depth.