Cigarette smoking increases plasma levels of IL-6 and TNF-α

Abstract

Background and objective: Cigarette smoking is a leading cause of a wide range of critical health problems such as cancers, especially those related to the respiratory system. Although studies are continuing on the smoking-related inflammatory responses, limited reports are there to explore how such responses can be affected by the smoking intensity. Therefore, the current communication aimed to shed light on how smoking and smoking intensity can affect some inflammatory and anti-inflammatory biomarkers. Methods: A total of 159 subjects (108 smokers and 51 non-smokers) were enrolled in this cross-sectional study. Their sociodemographic, smoking intensity and blood samples were obtained and processed using approved methodologies. The blood plasma samples were used to quantify interleukin 6 (IL-6), IL-10, tumor necrosis factor-alpha (TNF-α), C-reactive protein, D-dimer, and ferritin by using ELISA. The gained data was then analyzed using GraphPad Prism software to assess the variations. Results: Both IL-6 and TNF-α are elevated markedly (p<0.001) in smoker subjects when compared with non-smoker ones (IL-6: 2.58±0.98 vs. 1.858±0.6256 pg/ml, TNF-α: 28.38±7.162 vs. 22.64±7.257 pg/ml). However, no significant differences were observed in other biomarkers comparing the groups, as well as no significant association was evidenced based on smoking intensity among smokers. Conclusions: The findings might point to a relationship between smoking and the elevation of IL-6 and TNF-α levels in a cigarette dose-dependent manner.