An online search on PubMed.gov for “oxidative stress” yields more than 250,000 articles. Most practitioners know that oxidative stress is the chief cause of the majority of human diseases, yet few of us spend much time trying to lower it.
Add the word “eye” to the above search and you will find some 18,000 articles. The authors of this study, supported by the National Eye Institute, have reviewed 175 of these articles.
So, what exactly is oxidative stress? It’s “... when reactive oxygen species (ROS) cellular overproduction overwhelms intrinsic antioxidant capacity [and] damage to the biomolecules of normal cells and tissues ... occurs” (Dröge). ROS include superoxide, hydrogen peroxide, single oxygen and lipid peroxides. The most common blinding conditions we treat each day are a result of ROS.
One way the body fights harmful prooxidants is to respond through endogenous production of enzymatic antioxidants. The Nrf2 pathway is the key to upregulation of gene signaling and leads to robust antioxidant production.
Compounds, both natural and synthetic, that can activate Nrf2 and lead to production of superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase are being intensely studied. Synthetic Nrf2 activators such as Tecfidera (dimethyl fumarate, Biogen) are used to prevent relapse in multiple sclerosis. Natural compounds such as curcumin, green tea and sulforaphane show safe and promising results.
Batliwala and colleagues have offered a valuable review of this important topic showing the vital role of Nrf2 in managing specific diseases such as age-related macular degeneration. Unfortunately, they omitted a key article implicating OS in the pathogenesis of Fuchs dystrophy and keratoconus (Wojcik et al.).
Optometrists and ophthalmologists with an interest in epigenetics and functional medicine will integrate Nrf2 strategies as we seek to prevent and manage eye disease.
Dröge W. Physiol Rev. 2002;82(1):47-95;doi: 10.1152/physrev.00018.2001.
Wojcik KA, et al. Int J Mol Sci. 2013;14(9):19294-308;doi: 10.3390/ijms140919294.
Matt Dixon, OD
Advanced Eyecare Center
Disclosures: Dixon maintains a distributorship with LifeVantage Corp. but is not a stock holder.