AIM:To establish the model of age-related macular degeneration through blue light burning human retinal pigment epithelium(hRPE)cells in vitro and to investigate the possible mechanism of lycium barbarum polysaccharide(LBP)protecting the hRPE cells from blue light irradiation-induced damage.

METHODS: hRPE cells were cultured in Dulbecco's modified eagle's medium with high glucose and were pretreated with different concentrations(0.01mg/mL, 0.1mg/mL and 1mg/mL, respectively)of LBP solution, respectively. Further, hRPE cells were irradiated with different intensities(2000±500 LUX)of blue light(wave length 470-520nm)for 12h and the cellular morphology was observed by inverted phase contrast microscopy for every sample. Using flow cytometry, the alterations in the levels of reactive oxygen species, mitochondrial membrane potential and apoptosis were determined, respectively.

RESULTS: The level of reactive oxygen species in hRPE cells in blue-light treatment group was the highest, whereas the level in control group was the lowest. The fluorescent level of reactive oxygen species among different concentrations of LBP-treatment groups had specifically significant differences compared with that in blue light irradiation group(P<0.05). The amounts of apoptotic cells in different concentrations of LBP-treatment groups were specifically significant differences compared with that in blue light irradiation group(P<0.05); There were no apparent significant difference between 1mg/mL LBP-treatment group and normal control group(P>0.05).

CONCLUSION: LBP can efficiently inhibit apoptosis induced by blue light irradiation in hRPE cells and 1mg/mL of LBP has the strongest protective ability in blue light irradiation-induced damage in hRPE cells. The possible mechanism may attribute to the protective effect of LBP in inhibiting the overgeneration of reactive oxygen species and apoptosis in hRPE cells.