title: [The protective effect of photochromic intraocular lens on visible light-induced lesion in cultured retinal pigment epithelium].
abstract: OBJECTIVE
  To evaluate the protective effect of photochromic intraocular lens (IOL) on visible light-induced lesion in cultured retinal pigment epithelium (RPE).
  
  
  METHODS
  It was a experimental study. A human retinal pigment epithelium cell line (ARPE-19) was used to study the protective role. Cells from the same passage were divided into the control, light exposure only, light exposure plus colorless IOL (FV-60A), light exposure plus photochromic IOL (BV-60A), light exposure plus yellow IOL (Acrysof Natural IOL) groups. The treatments were performed when the cells grew to 90% confluency. All cells were irradiated with visible light at an illumination intensity of 60 000-61 000 lux. After the treatments, we assessed 1: cells' viability by methyl thiazolyl tetrazolium (MTT) assay; 2: the extent of apoptosis by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), observing changes in the ultrastructure by transmission electron microscopy (TEM), and performing Hoechst staining to measure the apoptosis index (AI); 3: examining vascular endothelial growth factor (VEGF) and pigment epithelium-derived factor (PEDF) levels in the culture medium by enzyme linked immunosorbent assay (ELISA).
  
  
  RESULTS
  Measurements of the cell viability of the five groups were (0.61 ± 0.01), (0.39 ± 0.01), (0.46 ± 0.01), (0.57 ± 0.01), and (0.58 ± 0.02), respectively. Apoptosis was significantly activated by visible light as observed in TUNEL staining and TEM. The AIs of the five groups were (0.99 ± 0.65)%, (9.28 ± 0.59)%, (6.54 ± 0.37)%, (4.69 ± 0.74)%, and (2.72 ± 0.67)%, respectively. The levels of VEGF in the five groups were (3931.64 ± 25.26) ng/L, (5459.38 ± 42.69) ng/L, (4800.55 ± 42.12) ng/L, (4561.21 ± 46.27) ng/L, and (4420.35 ± 28.66) ng/L, respectively. The levels of PEDF in the five groups were (182.85 ± 1.68) µg/L, (156.52 ± 0.64) µg/L, (155.57 ± 3.43) µg/L, (167.57 ± 2.88) µg/L, and (170.90 ± 2.99) µg/L, respectively. Comparing the photochromic IOL group with the yellow IOL group, there was no difference in cell viability (q = 0.94) and PEDF levels (q = 1.51) (P > 0.05), but there was a significant difference between the AI (q = 5.04) and VEGF levels (q = 6.78) (P < 0.05). Comparing the photochromic IOL group with the colorless IOL group, there were significant differences in cell viability (q = 18.92) , AI (q = 4.78) , VEGF (q = 11.52) and PEDF levels (q = 4.96) (P < 0.05).
  
  
  CONCLUSIONS
  Photochromic IOL can abate the degree of acute photodamage of RPE. The protective efficiency was the highest when using the yellow Acrysof Natural IOL, followed by photochromic IOL and colorless IOL.
authors.affiliation: Department of Ophthalmology, Affiliated Hospital of Nantong University, Nantong, China.
authors.forename: Jing-jing
authors.initials: JJ
authors.lastname: Qian
authors.forename: Huai-jin
authors.initials: HJ
authors.lastname: Guan
mesh_terms: D017209:Apoptosis; D002460:Cell Line; D002470:Cell Survival; D006801:Humans; D007910:Lenses, Intraocular; D008027:Light / Q000009:adverse effects*; D055213:Retinal Pigment Epithelium / Q000166:cytology*