N-acetylcysteine amide, a thiol antioxidant, prevents bleomycin-induced toxicity in human alveolar basal epithelial cells (A549).

Bleomycin (BLM), a glycopeptide antibiotic from Streptomyces verticillus, is an effective antineoplastic drug. However, its clinical use is restricted due to the wide range of associated toxicities, especially pulmonary toxicity. Oxidative stress has been implicated as an important factor in the development of BLM-induced pulmonary toxicity. Previous studies have indicated disruption of thiol-redox status in lungs (lung epithelial cells) upon BLM treatment. Therefore, this study focused on (1) investigating the oxidative effects of BLM on lung epithelial cells (A549) and (2) elucidating whether a well-known thiol antioxidant, N-acetylcysteine amide (NACA), provides any protection against BLM-induced toxicity. Oxidative stress parameters, such as glutathione (GSH), malondialdehyde (MDA), and antioxidant enzyme activities were altered upon BLM treatment. Loss of mitochondrial membrane potential (ΔΨm), as assessed by fluorescence microscopy, indicated that cytotoxicity is possibly mediated through mitochondrial dysfunction. Pretreatment with NACA reversed the oxidative effects of BLM. NACA decreased the reactive oxygen species (ROS) and MDA levels and restored the intracellular GSH levels. Our data showed that BLM induced A549 cell death by a mechanism involving oxidative stress and mitochondrial dysfunction. NACA had a protective role against BLM-induced toxicity by inhibiting lipid peroxidation, scavenging ROS, and preserving intracellular GSH and ΔΨm. NACA can potentially be developed into a promising adjunctive therapeutic option for patients undergoing chemotherapy with BLM.

N-acetylcysteine amide protects against methamphetamine-induced tissue damage in CD-1 mice.

Methamphetamine (METH), a highly addictive drug used worldwide, induces oxidative stress in various animal organs, especially the brain. This study evaluated oxidative damage caused by METH to tissues in CD-1 mice and identified a therapeutic drug that could protect against METH-induced toxicity. Male CD-1 mice were pretreated with a novel thiol antioxidant, N-acetylcysteine amide (NACA, 250 mg/kg body weight) or saline. Following this, METH (10 mg/kg body weight) or saline intraperitoneal injections were administered every 2 h over an 8-h period. Animals were killed 24 h after the last exposure. NACA-treated animals exposed to METH experienced significantly lower oxidative stress in their kidneys, livers, and brains than the untreated group, as indicated by their levels of glutathione, malondialdehyde, and protein carbonyl and their catalase and glutathione peroxidase activity. This suggests that METH induces oxidative stress in various organs and that a combination of NACA as a neuro- or tissue-protective agent, in conjunction with current treatment, might effectively treat METH abusers.