The activated water then attacks the thioester enzyme-substrate complex in nucleophilic reaction that regenerates the free enzyme, and releases the corresponding carboxylic acid.

Moderate UVR exposure oxidizes specific proteins that eventually serve as signaling agents for an array of metabolic and inflammatory pathways.

The eventual degradation of lipid hydroperoxides releases a wide variety of aldehydes, which, owing to their stability and ability to react cellular nucleophiles,[12] are both cytotoxic and genotoxic in nature.

[13][14] Its stability and multiple sites of reactivity (carbon-carbon double bond, hydroxyl group, and carbonyl) make 4HNE a potent inhibitor of cellular growth, enzyme activities, calcium sequestration, and protein synthesis.

Studies in which rabbits were transfected with genes that allow them to overexpress human ALDH3A1 in their corneal stromal fibroblasts document ALDH3A1's most critical function is to protect the cornea from oxidative stresses.

[23] Although the full scope of ALDH3A1's function is yet to be firmly established, there is strong evidence suggesting that ALDH3A1 serves to maintain the cellular redox balance as well as the structural integrity and transparency of the cornea.

ALDH3A1's absorption of UVR oxidizes several key amino acid residues, leading to conformational changes that convert the alpha and beta sheets into random coils.

[23] These observations on ALDH3A1-null mice reaffirm that ALDH3A1's role extends beyond enzymatic metabolism; encompassing functions in maintenance of the structural integrity and transparency of the cornea.