不同剂量低能量激光照射对体外人成骨样细胞增殖和分化的影响

目的:探讨不同剂量低能量激光(LLL)照射对人成骨样细胞增殖和分化的影响，为LLL的临床应用提供实验依据。方法：对数生长期人成骨细胞MG63随机分为3组，采用Ga-Al-As半导体激光器（808 nm,66 mW）进行照射，照射组1的剂量为1 J?cm-2，照射组2的剂量为 3 J?cm-2，对照组不进行激光照射。采用MTT法检测细胞增殖活力，免疫组化法检测细胞分化的标志骨桥蛋白（OPN）和Ⅰ型胶原蛋白（Coll Ⅰ）的表达情况。结果：与对照组比较，照射组1的细胞增殖活力和OPN、Coll Ⅰ表达量差异无显著性(P＞0.05)；24和48 h照射组2的细胞增殖活力明显高于对照组(P＜0.05)，且24 h时OPN、Coll Ⅰ表达量明显高于对照组(P＜ 0.05)。结论：3 J?cm-2剂量的低能量激光能促进人成骨样细胞的增殖和分化，可能促进骨修复。

Effect of low level laser irradiation with different doses on proliferation and differentiation of human osteoblast-like cells in vitro

Objective To investigate the effect of low level laser(LLL)irradiation with different doses on proliferation and differentiation of human osteoblast-like ceils,and provide the experimental basis for clinical application of LLL.Methods Human osteoblast-like cells MG63 were irradiated by Ga-Al-As diode laser(808 nm,66 mW)with doses of 1 J·cm~(-2) and 3 J·cm~(-2) after being seeded into multi-well plates.Untreated cells were used as controls.The proliferation of MG63 was quantified by colorimetric MTT(dimethyhhiazol tetrazolium bromide)assay.The expressions of the marker of differentiation osteopontin(OPN)and collagen Ⅰ(Coil I)were observed by immunohistochemistry assay.Results There was no difference of proliferation and expressions of OPN and Coil Ⅰ between the laser group with dose of 1 J·cm~(-2) and control group(P>0.05).The laser group with the dose of 3 J·cm~(-2) showed more increase in cell survival at 24 and 48 h after being seeded as compared with control group(P<0.05).Moreover,the expressions of OPN and Coil Ⅰ in the laser group with dose of 3 J·cm~(-2) was also higher than those in control group(P<0.05).Conclusion LLL irradiation with the dose of 3 J·cm~(-2) may promote the proliferation and differentiation of human osteoblast-like cells,which might improve bone healing.