骨質疏鬆與癌細胞骨轉移，皆可發現破骨細胞的活性明顯增加。有研究顯示癌細胞骨轉移時，破骨細胞對於骨質的破壞，大於癌細胞的影響。 癌細胞轉移至骨組織常造成骨組織破壞及引起骨骼疼痛，目前常以游離輻射局部照射來加以處理，而由於低能量氦氖雷射已被發現可促進受傷骨組織進行修復作用，為瞭解其作用機制，本研究利用低能量氦氖雷射評估其對破骨細胞分化的影響，並同時比對游離輻射對破骨細胞的影響。本研究採分離人類周邊幹細胞與造骨細胞共同培養之模式，以誘發破骨細胞的分化，進而給與不同條件刺激，觀察其差異。結果顯示接受雷射照射組，其破骨細胞分化的數目相對少於對照組，但對已分化之破骨細胞的活性則較無影響，顯示低能量氦氖雷射可經由抑制分化的方式抑制破骨細胞。此外，游離輻射(10 Gy)照射組所得到的結果顯示其對破骨分化之抑制作用較氦氖雷射照組為小，但對於已分化之破骨細胞，其抑制作用則很明顯。由此可知低能量氦氖雷射與游離輻射經由不同的機制抑制破骨細胞的分化；由RT-PCR分析破骨細胞分化因子的製造即可獲得証實。因此，低能量氦氖雷射與游離輻射均可抑制破骨細胞的分化數目，但前者是透過減少造骨細胞分泌破骨細胞分化因子來達成抑制破骨細胞的分化，就抑制破骨細胞數量方面效果較佳，但游離輻射照射對於破骨細胞的活性則有明顯的抑制作用。故應用低能量氦氖雷射以輔助治療骨質疏鬆症，應有一定的可行性。 The activity of osteoclast are obviously increased both in osteoporosis and bone metastasis of cancer cells. The destruction of bone by osteoclast was severer than that by cancer cells in bone metastasis as reported in literature1. Metastasis of cancer cell to bone tissues usually causes bone damages and bone aches. Presently, they are approached with ionizing radiation. On the other hand, low-energy He/Ne laser has been found able to enhancing restoration of damaged bone tissues. In order to investigate the associated mechanism, we utilized lowenergy He/Ne laser to evaluate its influence on the differentiation of osteoclasts. Meanwhile, we compared the above results with those using ionizing radiation. In this study, we co-cultured peripheral stem cells of human with osteoblasts to initiate the differentiation of osteoclasts, and investigated the difference when giving various stimuli. The results shown that the number of differentiating osteoclasts was relatively smaller under the irradiation of low -energy He/Ne laser than that of the control group. However, no apparent effect was observed on the activity of differentiated osteoclasts. This represented that low-energy He/Ne laser were capable of suppressing osteoclasts by their differentiation. Besides, the suppressing ability of ionizing radiation (10 Gy) on osteoclast differentiation was lower than that of low-energy He/Ne laser. Nevertheless, the suppression was apparent on the differentiated osteoclasts. According to these results, the differentiation of osteoclasts was suppressed through two different mechanisms by low-energy He/Ne laser and the ionizing radiation, which was proved by RT-PCR analysis on the production of osteoclast differentiation factors. Therefore, both low-energy He/Ne laser and ionizing radiation were capable of inhibiting osteoclast differentiation, however, the former worked through reducing the secretion of osteoclast differentiation factors from osteobalsts. For the suppression of production of osteoclasts,this mechanism appeared to be more effective. Consequently, this study indicats that the utilization of low-energy He/Ne laser should have provided an alternative method in assisting the healing process of osteoporosis.
