CHAPTER 6: Glutathione and Thiol Redox Signalling in Parkinson’s Disease

Glutathione (GSH) and thiol redox signalling are at the most basic level of cellular redox reactions and responses to oxidative stress. Oxidative stress plays a major role in the etiology of Parkinson’s disease. Reactive oxygen species (ROS) and reactive nitrogen species (RNS) that cause this stress may be generated by a number of factors, including byproducts generated by oxidative phosphorylation in the mitochondrial production of ATP, exposure to toxic environmental agents, inflammation and secondary effects of genetic mutations. The known characteristics of dopaminergic (DA) neurons combined with the permissive cytoarchitecture of the substantia nigra pars compacta (SNpc) provide an environment that makes these cells particularly vulnerable in the event of oxidative stress. The antioxidant tripeptide GSH, cysteine residues, and the thiol redox reactions in which they participate, function to reduce oxidative stress and protect cells from their sequelae. In this chapter, we discuss the factors that contribute to oxidative stress in the SNpc and Parkinson’s disease, as well as mechanisms by which GSH synthesis, thiol-disulfide exchange and thiol-modulated enzymes can modulate gene transcription during oxidative stress.