Modulating antioxidant systems as a therapeutic approach to retinal degeneration

The human retina is facing a big challenge of reactive oxygen species (ROS) from endogenous and exogenous sources. Excessive ROS can cause damage to DNA, lipids, and proteins, triggering abnormal redox signaling, and ultimately lead to cell death. Thus, oxidative stress has been observed in inherited retinal diseases as a common hallmark. To counteract the detrimental effect of ROS, cells are equipped with various antioxidant defenses. In this review, we will focus on the antioxidant systems in the retina and how they can protect retina from oxidative stress. Both small antioxidants and antioxidant enzymes play a role in ROS removal. Particularly, the thioredoxin and glutaredoxin systems, as the major antioxidant systems in mammalian cells, exert functions in redox signaling regulation via modifying cysteines in proteins. In addition, the thioredoxin-like rod-derived cone viability factor (RdCVFL) and thioredoxin interacting protein (TXNIP) can modulate metabolism in photoreceptors and promote their survival. In conclusion, elevating the antioxidant capacity in retina is a promising therapy to curb the progress of inherited retinal degeneration.

Automated summary

The human retina is exposed to reactive oxygen species (ROS) from both internal and external sources, which can cause oxidative stress and lead to damage and cell death. This review focuses on the antioxidant systems in the retina and how they protect against oxidative stress. Both small antioxidants and antioxidant enzymes are involved in the removal of ROS, with the thioredoxin and glutaredoxin systems playing a major role in regulating redox signaling. Additionally, the proteins RdCVFL and TXNIP are involved in metabolic regulation and promoting survival in photoreceptors. Increasing antioxidant capacity in the retina shows promise as a therapy for inherited retinal degeneration.