Chapter 15 - Biological thiols and redox regulation of cellular signal transduction pathways

Abstract

This chapter discusses the biological thiols and redox regulation of cellular signal transduction pathways. Thiols refer to a class of organic sulfur derivatives that are characterized by the presence of sulfhydryl residues (–SH) at their active site. They can also act as reducing agents. The chapter discusses the way a low physiologically relevant concentration of reactive oxygen species (ROS) can regulate a variety of key molecular mechanisms that may be linked with important cell functions. The chapter describes several proteins with apparent redox-sensing activity. The ubiquitous endogenous thiols thioredoxin and glutathione (GSH) are of central importance in redox signaling. Protein phosphorylation, which is one of the most fundamental mediators of cell signaling, is redox sensitive. DNA-binding proteins are involved in the regulation of cellular processes, such as replication, recombination, viral integration, and transcription. Though several thiol agents are being tested for their efficacy to modulate cellular redox status, N-acetyl-L-cysteine and α–lipoic acid hold most promise for human use.