Cellular S-denitrosylases: Potential role and interplay of Thioredoxin, TRP14, and Glutaredoxin systems in thiol-dependent protein denitrosylation

Nitric Oxide is a very well known gaseous second messenger molecule and vasorelaxant agent involved in a variety of signaling in the body such as neurotransmission, ion channel modulation, and inflammation modulation. However, it's reversible covalent attachment to thiol groups of cysteine residues under nitrosative stress leading to aberrant protein S-nitrosylation (P-S-N=O) has been reported in several pathological conditions in the body stemming from neurodegenerative diseases, cancer, cardiovascular system, and immune system disorders. In the cell, PSNOs are partly unstable and transit to a more stable disulfide state serving as an intermediate step towards disulfide formation thus eliciting the biological response. Scientists have identified several cellular thiol-dependent disulfide reductases that have the intrinsic capability to reverse the modification by reducing the stable disulfides formed in PSNOs and thereby rescue S-nitrosylation-induced altered proteins. The physiological roles of these major cellular ubiquitous S-denitrosylases and their probable implementations have not been fully explored. Gaining knowledge from current research and development this review provides a deeper insight into understanding the interplay and role of the major ubiquitous S-denitrosylases in maintaining cellular redox homeostasis. This review umbrellas the mechanism of Thioredoxin, TRP14, and Glutaredoxin systems and highlights their substrates specificities at different cellular conditions, physiological roles, and importance in diseased conditions that would allow researchers to investigate effective therapeutic interventions for nitrosative stress-related diseases and disorders.