title: [The correlation between the concentrations of VEGF and PEDF and Ca2+-PKC signaling pathways in human retinal pigment epithelial cells cultured in vitro after exposuring to blue light].
abstract: OBJECTIVE
  To investigate the concentrations of vascular endothelial growth factor (VEGF), pigment epithelium-derived factor (PEDF), inositol triphosphate (IP3) and diacylglycerol (DAG) in human retinal pigment epithelium (RPE) cells after exposuring to blue light, and to explore the relationship with Ca2+-PKC signaling pathways, to evaluate the role of Ca2+-PKC signaling pathways of blue-light irradiation induced apoptosis in RPE cells.
  
  
  METHODS
  The fourth generation human RPE cells in vitro were exposured to blue light (2000±500 lux) for 6 hours, 24 hours prolongation of post-exposure culture. The concentrations of VEGF, PEDF, IP3 and DAG were assayed by enzyme linked immunosorbent assay (ELISA). Cells were randomly divided into 6 groups, group A (control), group B (exposure to blue light), group C (exposure to blue light+PMA), group D (exposure to blue light+Calphostin C), group E (exposure to blue light+Nifedipine), group F (exposure to blue light+Calphostin C+Nifedipine). Flow cytometry was used to detect the apoptosis rate of human RPE cells in A, B and F group.
  
  
  RESULTS
  Comparing with group A (584.38±10.66), the concentration of VEGF in group B (700.70±5.88), group C (698.21±6.66) and group E (648.30±4.91) was higher, the difference was statistically significant (P=0.002, 0.002, 0.016). Comparing with group B (700.70±5.88), the concentration of VEGF in Group D (623.87±3.12) and E (648.30±4.91) was lower (P=0.001, 0.002). Comparing with group A (75.96±1.70), the concentration of PEDF in Group B (71.82±1.67) and C (72.43±0.58) was lower (P=0.004, 0.011), but the concentration of PEDF in Group D (86.31±1.35) and E (93.72±1.24) was higher (P=0.000, 0.000). Comparing with group B (71.82±1.67), the concentration of PEDF in Group D (86.31±1.35) and E (93.72±1.24) was higher (P=0.000, 0.000). Comparing with group A (7.70±0.29), the ratio of VEGF to PEDF in Group B (9.85±0.34) and Croup C (9.64±0.02) was higher (P=0.008, 0.027) Comparing with group B, The ratio of VEGF to PEDF in Group D (7.23±0.08) and E (6.92±0.06) was lower (P=0.016, 0.015). Comparing with group A (108.42±0.75, 995.47± 13.61), the concentration of IP3 and DAG in Group B (117.24±1.06, 1070.10±10.07), C (137.12±2.71, 1046.40±7.90), D (139.17±1.40, 1041.13±9.76) and E (149.61±0.77, 1273.14±10.89) was higher, the difference was statistically significant (P=0.003, 0.007, 0.000, 0.000, 0.000, 0.000, 0.000, 0.000). Comparing with group B, the concentration of IP3 in Group C, D and E was higher (P=0.011, 0.000, 0.000). Comparing with group B, the concentration of DAG in Group C and D was lower (P=0.021, 0.007). Comparing with group B, the concentration of DAG in Group E was higher (P=0.000). Comparing with group A (10.27±1.88), the apoptosis rate of RPE cells in Group B(25.07±2.66) and F(19.37±3.23) was higher, the difference was statistically significant (P=0.001, 0.009). Comparing with group B (25.07±2.66), the apoptosis rate of RPE cells in Group F (19.37±3.23) was lower (P=0.038).
  
  
  CONCLUSIONS
  (1) After exposuring to blue light, the concentrations of VEGF, IP3 and DAG are increased and the ratio of VEGF to PEDF is also increased and the concentration of PEDF is decreased in human RPE cells. (2) L-Type Calcium Channels and Ca2+-PKC signaling pathways may be regulate the concentrations of VEGF, PEDF, IP3 and DAG in RPE cells after exposuring to blue light by feedback regulation. (3) The application of Calphostin C combined with Nifedipine may be restrain the apoptosis of RPE cells after exposuring to blue light.
authors: Department of Ophthalmology, the Hospital Affiliated to Zunyi Medical School, Zunyi 563003, China.
authors: Limin
authors: L
authors: Wang
authors: Department of Ophthalmology, the Hospital Affiliated to Zunyi Medical School, Zunyi 563003, China; Email: caishanjun@163.com.
authors: Shanjun
authors: S
authors: Cai
authors: Department of Ophthalmology, the Hospital Affiliated to Zunyi Medical School, Zunyi 563003, China.
authors: Zhipeng
authors: Z
authors: Wu
authors: Department of Ophthalmology, the Hospital Affiliated to Zunyi Medical School, Zunyi 563003, China.
authors: Xin
authors: X
authors: Gong
authors: Department of Ophthalmology, the Hospital Affiliated to Zunyi Medical School, Zunyi 563003, China.
authors: Jianping
authors: J
authors: Lyu
authors: Department of Ophthalmology, the Hospital Affiliated to Zunyi Medical School, Zunyi 563003, China.
authors: Gang
authors: G
authors: Su
authors: Department of Ophthalmology, the Hospital Affiliated to Zunyi Medical School, Zunyi 563003, China.
authors: Lili
authors: L
authors: Wang
mesh_terms: D017209:Apoptosis; D020746:Calcium Channels, L-Type; D002478:Cells, Cultured; D004075:Diglycerides / Q000032:analysis* / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism / Q000528:radiation effects; D005136:Eye Proteins / Q000032:analysis* / Q000378:metabolism; D006801:Humans; D007295:Inositol Phosphates / Q000032:analysis / Q000378:metabolism; D008027:Light; D009281:Naphthalenes / Q000494:pharmacology; D009414:Nerve Growth Factors / Q000032:analysis* / Q000378:metabolism; D009543:Nifedipine / Q000494:pharmacology; D010857:Pigment Epithelium of Eye / Q000166:cytology / Q000378:metabolism / Q000528:radiation effects*; D011493:Protein Kinase C / Q000032:analysis* / Q000378:metabolism; D011897:Random Allocation; D012168:Retinal Pigments; D015843:Serpins / Q000032:analysis* / Q000378:metabolism; D015398:Signal Transduction; D014212:Tretinoin / Q000528:radiation effects; D042461:Vascular Endothelial Growth Factor A / Q000032:analysis* / Q000378:metabolism; D000099174:Pigment Epithelium-Derived Factor
chemical_list: D020746:Calcium Channels, L-Type; D004075:Diglycerides; D005136:Eye Proteins; D007295:Inositol Phosphates; D009281:Naphthalenes; D009414:Nerve Growth Factors; D009543:Nifedipine; D011493:Protein Kinase C; D012168:Retinal Pigments; D015843:Serpins; D014212:Tretinoin; D042461:Vascular Endothelial Growth Factor A; D000099174:Pigment Epithelium-Derived Factor; C092449:inositol 1,2,3-trisphosphate; C058819:calphostin C