不同波长LED光源对大鼠晶状体影响的初步研究

Effect of light-emitting diode light of different wavelengths on the rat lens: a preliminary study

目的分别观察峰值波长为622.791、509.699、462.826 nm的LED光源(CT=4500 K,照度500勒克斯)对活体大鼠晶状体组织形态及晶状体内SOD、GSH-Px及MDA含量的影响。总结LED光源波长与晶状体所受影响程度之间的关系及变化趋势,为安全绿色环保的LED光源使用及制造提供实验室依据。方法选取6周龄SD大鼠,雌雄不限,将SD大鼠随机分为4个组,即对照组、红光组、绿光组、蓝光组。对照组大鼠使用黑色塑料膜遮盖,饲养于黑暗环境中;另外3个组分别给予红光(峰值波长为622.791 nm)、绿光(峰值波长为509.699 nm)及蓝光(峰值波长为462.826 nm)照射环境饲养,环境照度均为500勒克斯,色温为4500 K。连续照射5 d(12 h明-12 h暗,6∶00 a.m.-18∶00 p.m.),各组实验环境均保持(20.0~23.5)℃,湿度为35.5%~65.5%。实验结束后取大鼠晶状体组织,HE染色观察晶状体变化,使用全自动生化检测仪检测晶状体内MDA、SOD及GSH-Px含量。结果HE染色显示对照组大鼠晶状体上皮细胞形态扁平,单层排列,整齐一致;蓝光组大鼠晶状体上皮细胞呈现细胞排列紊乱、肿胀,晶状体上皮细胞由正常的单层分布改变为双层甚至多层排列的形态;绿光照射组细胞轻度肿胀,部分区域呈现双层排列形态;红光组大鼠晶状体上皮细胞呈现单层、扁平、排列整齐的形态,与对照组一致。大鼠晶状体内MDA含量分别为对照组0.0043、蓝光组0.0178 U/mgprot、绿光组0.0156 U/mgprot、红光组0.0044 U/mgprot,除红光组与对照组间差异无统计学意义(P>0.05)外,其余各组间比较差异均有统计学意义(P<0.05)。对照组,蓝、绿、红光照射组大鼠晶状体内SOD含量分别约为1.3067、2.1233、3.0700、7.9267 U/mgprot,各组间比较差异有统计学意义(P<0.05);对照组,蓝、绿、红光照射组大鼠晶状体内GSH-Px含量分别约为1.4133、2.1590、2.6960、9.7933 U/mgprot,各组间比较差异有统计学意义(P<0.05)。结论LED光对晶状体上皮细胞的影响具有波长相关性,波长越短的LED光线对晶状体上皮细胞形态改变影响越大,导致晶状体内超氧化物歧化酶、谷胱甘肽过氧化物酶活性下降越明显,使晶状体内脂质过氧化物堆积更为显著。

Objective This study was aimed at exploring the effects of light-emitting diode(LED)light of different peak wavelengths(622.791,509.699,and 462.826 nm)on the rat lens,including damage to the morphology of the lens epithelial cells.Further,we tested the activities of the antioxidant enzymes superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)in the lens and compared the malondialdehyde(MDA)activity in the lens after irradiation by LED of different wavelengths.Methods Sprague Dawley rats were irradiated with LED light of different peak wavelengths(color temperature=4500 K;illuminance:500 lux)12 h a day for 5 days.Hematoxylin and eosin(HE)staining was used to observe the paraffin sections of rat lens epithelial cells.The activities of SOD,GSH-Px,and MDA in the lens were detected by the automatic biochemical analyzer.Results HE staining showed that lens epithelial cells in the control group were flat,monolayer,and uniform.In the blue-light group,lens epithelial cells were disordered,swollen,and changed from a single layer to double or even multiple layers.In the green-light group,lens epithelial cells were slightly swollen,and some areas showed a double-layer arrangement.In the red-light group,lens epithelial cells were flat,monolayer and uniform too.MDA activities in the rat lens of the control and red-,green-,and blue-light groups were approximately 0.0043,0.0044,0.0156,and 0.0178 U/mgprot,respectively.There were no significant differences between the red-light and control groups(P>0.05),but there were significant differences among the other groups(P<0.05).SOD activities in the lens of the control and red-,green-,and blue-light groups were 1.3067,7.9267,3.0700,and 2.1233 U/mgprot,respectively,showing significant differences(P<0.05).GSH-Px activities in the lens of the control and red-,green-,and blue-light groups were 1.4133,9.7933,2.6960,and 2.1590 U/mgprot,respectively,showing significant differences(P<0.05).Conclusion The influence of LED light on rat lens epithelial cells is wavelength-dependent.Shorter wavelengths of LED light are associated with greater changes in the lens epithelial cell morphology,greater effects of SOD and GSH-Px activities in the lens,and more lipid peroxide accumulation in the lens.