Smoking and COPD are associated with oxidative stress, which is classically defined as the result of an imbalance between oxidants and antioxidants substances. The advanced glycation end products (AGEs) are the result of protein carbonyls, a reaction that stems from lipid peroxidation and glycoxidation which release products that will react with proteins damaging them and are responsible for various manifestations associated with aging, diabetes mellitus, cardiovascular disease and the development of cancer and metastases. In addition, toxic products of glycation are also present in aqueous extracts of tobacco and can react rapidly with proteins to form AGEs and products as methylglyoxal and glyoxal (AGEs precursors) are found in tobacco smoke. In this direction, it was found that the concentration of AGEs is higher in smokers and COPD patients compared to nonsmokers, independently of the presence of diabetes.
Cerami et al.found induction of AGEs after in vitro preparation of aqueous extract and in condensate of tobacco and increased concentrations of AGEs in vivo when compared nonsmokers and smokers. This result is in agreement with study showing positive association between smoking history and AGEs concentrations evaluated by skin auto-fluorescence technique.