Expressions of apoptotic protein and gene following sulfur mustard-induced acute pulmonary injuries in rats.

OBJECTIVES

Pathomechanisms of sulfur mustard (SM) are not fully understood, and no specific medical countermeasures exist to prevent SM-induced pulmonary injury. This study aimed to evaluate the apoptosis following SM-induced acute pulmonary injury.

MATERIALS AND METHODS

Acute pulmonary injury models were established using SM at an equivalent toxicity dose (1 LD50), administered via intraperitoneal injection or intratracheal instillation. Protein expression levels and mRNA expressions of apoptosis-related markers, including cellular inhibitor of apoptosis proteins-1 and -2 (cIAP-1, cIAP-2), Fas, Bcl-2-associated death promoter (Bad), second mitochondria-derived activator of caspases (Smac), and survivin (BIRC5), were analyzed using immunohistochemistry and polymerase chain reaction.

RESULTS

The intraperitoneal SM group exhibited significantly higher levels of apoptotic cells in the alveolar septa and increased protein and mRNA expression of cIAP-1, cIAP-2, Fas, Bad, Smac, and BIRC5 compared to the intratracheal SM group. These changes displayed a time-dependent increase in both protein and gene expression levels.

CONCLUSION

SM-induced pulmonary injury involves both extrinsic (Fas, cIAP-1, cIAP-2) and intrinsic (Bad, Smac) pathways as well as caspase-dependent pathways (BIRC5). These findings provide valuable insights into the underlying mechanisms of SM toxicity and may facilitate the development of targeted therapeutic strategies.