- 學位論文
可見光刺激人類皮膚纖維母細胞生長之影響
Effect of Visible Light on Human Foreskin Fibroblast Cells
摘要
利用光刺激來促進傷口癒合，到現在已經研究約三、四十年，但由於早期只能利用雷射進行研究，波長的選擇有限，操作也較不方便，因此所獲得的結果也不相同。 為了能夠瞭解光刺激各種參數對皮膚癒合相關細胞之影響，我們使用LED為光源，針對皮膚纖維母細胞，有系統地探討在各種不同操作參數組合下對細胞的影響。本研究所控制的變數，除了波長（460, 578, 630 nm）外，也包含刺激時機（植入後第12或24小時）、頻率為1次/天的刺激次數（1-4次）、刺激強度（5-20 mW/cm2）和刺激時間（100-1600 s），並除此之外也總實施能量固定下，在高低強度刺激對纖維母細胞之影響。 最佳刺激參數主要是利用細胞增生來獲得。得到最佳刺激參數後，也觀察光刺激纖維母細胞後的type I 膠原蛋白、TGFβ與KGF分泌的變化。 研究結果發現，以紅光630nm刺激強度為20 mW/cm2刺激細胞，單次刺激就會促使細胞增生效果顯著。然而若以5 mW/cm2刺激則必須400秒，細胞才會有顯著增加。而我們發現刺激波長在黃光和藍光下沒有顯著的刺激效果。在比較長時間的刺激下，藍光的刺激甚至會抑制細胞生長。總實施能量方面不論在2、4、6、8 J/cm2下，細胞成長並沒有很大差別。我們也發現，以低強度（5mW/cm2）刺激長時間的光刺激反應的效果最為快速。 分析光刺激對纖維母細胞之膠原蛋白基因表現，發現光刺激並不會提升膠原蛋白基因表現；在細胞激素方面，以紅光630nm、5 mW/cm2刺激800秒會使細胞在刺激後0.5小時分泌更多TGF-β1與KGF。而TGF-β1與KGF細胞激素經由光刺激增加，表示光刺激可能可以促進傷口癒合。
並列摘要
To studies on wound healing enhancement by laser stimulation started from 40 years ago. The limited selectable wavelength and the bulky size restricted the extensive studies of various operating variables. Therefore, the effect of light stimulation on wound healing enhancement was still under debating. In this study, we start from investigating the effect of light stimulation on one of the wound healing related cells, human foreskin fibroblast. In order to thoroughly understand the effects of light, we used light-emitting diode (LED) light to simultaneously investigate all the controllable parameters, which include wavelength and power density of stimulating light, treating time per exposure, time interval between treatments, as well as the total applied energy. At the same total applied energy, comparisons were made between irradiations under high and low power densities but. The suitable stimulating parameters were mainly searched by cell proliferation. After stimulating conditions were found, the effects of light on fibroblasts were further examined by the secretion of type I collagen, transforming growth factor β1 (TGF-β1) and keratinocyte growth factor (KGF). The results showed that single dose of light treatment was sufficient to accelerate fibroblast proliferation when cells wee exposed under red light (630nm) at a power density of 20mW/cm2. However, when cells were irradiated at the same wavelength but at a power density of 5mW/cm2, it needed at least 400 seconds to achieve significant growth increment. We did not find significant growth acceleration when cells were exposed to yellow and blue lights. Long time exposure to the blue light even inhibited the cell growth. The cell growth was not sensitive to the total applied energy. Similar cell increments were obtained no matter cells were treated t a total energy of 2, 4, 6 or 8 J/cm2. It was also found that cells were more responsive to long time irradiation at low intensity (5mW/cm2). We did not observe significant increase in the expression of type I collagen. But when we treated the cells by a 630nm red light at 5mW/cm2 for 800 seconds, the secretion of TGF-β1 and KGF increased significantly an half an hour after the treatment. The increase in TGF-β1 and KFG indicated that it might be possible to enhance wound healing through light treatment.