An isolated polynucleotide encoding human glutamate cysteine ligase and human glutathione synthase, as well as expression constructs, vectors and pharmaceutical compositions comprising the same, are provided herein. Methods for use of these compositions in the treatment oxidative stress related diseases, including, for example, atherosclerosis, Parkinsons disease, heart failure, myocardial infarction, Alzheimers disease, diabetes, chronic lung disease, diseases associated with mitochondrial dysfunction, diseases associated with chronic inflammation, retinitis pigmentosa, wet age related macular degeneration, dry age related macular degeneration, diabetic retinopathy, Lebers optic neuropathy, and optic neuritis are also provided.
