Effect of Nicotine on Pulmonary Pathogenic Bacteria

Exposure to cigarette smoke significantly enhances susceptibility to bacterial infections by inducing physiological and structural alterations, including immune system dysregulation. This exposure also augments bacterial virulence including biofilm formation, leading to severe infectious diseases and antibiotic resistance. Notably, cigarette smoke exposure increases the incidence of pneumonia by up to 2.5-fold and tuberculosis by up to 4.1-fold. Nicotine, a primary constituent of cigarette smoke, has been extensively characterized for its immunomodulatory effects. However, despite the wealth of knowledge on nicotine's impact on the host immune response, there is a paucity of data regarding its direct effects on various pulmonary pathogens. In the present review, we discuss the main findings in this field.