To further know the signaling pathways involved in hypoxia-induced apoptosis in retinal pigmented epithelial (RPE) cells and to improve the understanding of the antioxidant N-acetyl-cysteine (NAC) treatment effect.
Methods:
We analyzed the expression levels of several apoptosis-related genes by semiquantitative reverse transcriptase–polymerase chain reaction in RPE after 72 h of maintained hypoxia, with or without 10 mM NAC treatment.
Results:
Under hypoxic conditions, we detected a higher expression level of p53 and CASP8. Cell treatment with NAC 10 mM prevented this increase. Other apoptosis-related genes such as bax, CASP3, CASP4, CASP7, and fas did not show an increase in expression levels in hypoxia.
Conclusions:
NAC prevents the increased expression levels of p53 and CASP8 induced by long-term maintained hypoxia. The supply of antioxidants could be a useful preventive approach in protecting RPE from the effects of chronic oxygen stress, which is of great interest in oxygen stress-related diseases such as age-related macular degeneration and other senescence-associated pathologies.
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