Biochemical Effect of Nicotine on Oxidative Stress and Inflammatory Markers in Lung

Studies regarding nicotine related lung toxic effects are contradictory and limited. This study aimed to evaluate nicotine toxic effect on lung tissues in the light of increased lipid peroxidation (MDA), disrupted antioxidants (GPx, GSH), elevated proinflammatory cytokines (TNF-α, NF-κB) and inflammatory mediated enzyme (Caspase-1). Twenty rats were divided into 2 groups; group I control and group II rats injected intraperitoneally with nicotine. After the experiment, nicotine injection significantly elevates (P<0.0001) MDA levels and, conversely, caused significant reduction in antioxidants (GPx and GSH) pulmonary levels. Also, there was remarkable upregulated NF-κB mRNA expression (8.34-fold increase) in the lung tissues associated with nicotine injection. Also, nicotine injection was associated with significant elevation of the pro-inflammatory cytokine Tumar Necrosis Factor (TNF-α) and inflammatory mediated enzyme Caspase-1. Therefore, it was concluded that nicotine has toxic effects on lung tissues as it elevates lipid peroxidation, increases pulmonary oxidative and inflammatory toxicity and abolished antioxidant capacity.