Inhibition of light-induced apoptosis of RPE cells by recombinant human erythropoietin / 中国药理学通报

ABSTRACT

Aim This study aimed to assess the protection of recombinant human erythropoietin (rhEPO) in light-induced injuries in human retinal pigment epithelial(RPE)cells by researching the inhibition of rhEPO for apoptosis in human RPE cells by light-induced injuries.Methods Cultured human RPE cells were exposed to light of 8 w (2 000?500) lux for 12hours,then the culture were stopped at 24 hours after 12hours light stimulation. The effect of inhibiting apoptosis of rhEPO was detected by AnnexinV-flunorescein isothiocyanate/Propidium iodium labeling and flow cytometry. The enzyme linked immunosorbant assay(ELISA)and immunocytochemical staining were used to assess the expressions of caspase-3 and Bcl-2 treated by different doses of rhEPO in light-induced injury on human RPE cells and research the protective mechanism of rhEPO by adding AG490(the special inhibitor of Jak2).Results There was a obviously increased effects on inhibiting apoptosis in every rhEPO group, which was the most conspicuous in 40 IU?ml-1 rhEPO group,and the value was (4.93?1.45)?ml-1. The decrease of expression of caspase-3 was most obvious in 40 IU?ml-1 rhEPO group, and the value was (0.125?0.029) ?g?L-1. The increase of expression of Bcl-2 was the most obvious in 40 IU?ml-1 rhEPO group and the value was 168.21?3.87. But these effects on inhibiting apoptosis in rhEPO group were restrained by adding AG490, the value of apoptosis was (11.29?2.11)?ml-1 and the density of caspase-3 increased to (0.362?0.042) ?g?L-1,the expression of Bcl-2 dropped.Conclusion It is suggested that rhEPO can inhibit the apoptosis of human RPE cells in the light-induced injuries and inhibit the expression of caspase-3 and up-regulate the expression of Bcl-2, so rhEPO can protect the light-induced injuries for human RPE cells. Its protective mechanism is accomplished principally by the pathway of combining EPO with EPOR ,then the combination activates Jak2.