胶原合成介导的软骨细胞的光生物调节作用

目的:了解低强度激光照射对软骨细胞增殖的影响及其机制。方法:选取3周龄新西兰白兔分离培养软骨细胞,在2.5%新生牛血清中培养,用半导体激光(650 nm,2.96 mW/cm2)(sem iconductor laser irrad iation,SLI)照第4代软骨细胞,每天分别照射1 m in、3 m in、5 m in、7 m in、10 m in、20 m in,共6 d。收集激光照射后第2 d、4 d、6 d、8 d、10 d和12 d的细胞培养液,用氯胺T消化法检测羟脯氨酸(H rp)的含量。在培养至第13 d时,用XTT法检测细胞的活性,了解细胞的增殖情况。结果:在2.5%新生牛血清中,SLI对软骨细胞具有明显的光生物调节作用:(1)在培养至第13 d时,所有剂量组在照射后XTT吸光度值均有不同程度的增高,其中3 m in、5 m in、7 m in和10 m in组的增高较为明显(P<0.01);(2)两因素重复测定资料的方差分析结果显示,SLI照射后软骨细胞合成胶原的能力在逐步增加,而对照组在培养至第2周开始H rp含量明显下降。结论:SLI照射可促进2.5%新生牛血清中兔软骨细胞增殖,这个过程可能是通过促进胶原合成实现的。

Collagen Synthesis Mediated Chondrocyte Photobiomodulation in vitro

Objective:the effects of low intensity laser irradiation on the chondrocyte proliferation and its mechanism were studied.Methods: the chondrocytes isolated from the cartilage sample of 3-week-old New Zealand white rabbits were cultured with 10 % newborn calf serum(NCS),irradiated by 650 nm semiconductor laser irradiation(SLI) at 2.96 mW/cm2 for 1 min,3 min,5 min,7 min,10 min and 20 min per day for 6 days,and then incubated till the 13th day at 2.5 % NCS.The type II collagen synthesis was assessed by a hydroxyproline(Hpr) content measurement on the 2nd,4th,6th,8th,10th and 12th day after the first SLI irradiation,respectively.The proliferation on the 13th day was assessed by a XTT assay.Results:There is significant photobiomodulation on the proliferation of the chondrocytes cultured at 2.5 % NCS.(1) The chondrocyte proliferation was significantly(P<0.01) promoted for the groups irradiated by SLI for 3,5,7 and 10 min,respectively,on the 13rd day;(2) The type II collagen synthesis increased steadily with days in the group irradiated by SLI for 5 min.Conclusions: the proliferation of the chondrocyte cultured at 2.5 % NCS might be promoted by SLI,which might be mediated by collagen synthesis.