Thioredoxin-1 suppresses systemic inflammatory responses against cigarette smoking.

Thioredoxin-1 (TRX) is a small redox-active protein with antioxidative effects and redox-regulating functions. Cigarette smoking is a major etiological factor in the pathogenesis of a variety of diseases and recruits systemic immune and inflammatory responses. This report demonstrates that TRX attenuates the systemic inflammatory responses induced by cigarette smoking. The mRNA expressions of tumor necrosis factor alpha (TNF-alpha) and macrophage migration inhibitory factor (MIF) were suppressed in the spleen of TRX overexpressing transgenic mice (TRX-tg) exposed to cigarette smoking, compared with control C57BL/6 mice. In addition, protein carbonylation, a marker of cellular protein oxidation, was enhanced by cigarette smoking in the tissues of heart and liver in control mice more than in TRX-tg mice. These findings suggest that TRX may suppress the systemic inflammatory responses against cigarette smoking.