Reduction of molecular oxygen by redox active thiols: comparison of glutathione, N-acetylcysteine, cysteine, and homocysteine

This in vitro study compared the redox activity of four thiol compounds—glutathione (GSH), N-acetylcysteine (NAC), cysteine (Cys), and homocysteine (HCS)—to evaluate their potential to reduce molecular oxygen and influence oxidative or reductive stress. The researchers found that GSH and Cys can reduce O₂ to generate reactive oxygen species (ROS), particularly