Genetic polymorphisms and their involvement in the regulation of the inflammatory response in asthma and COPD

Asthma and chronic obstructive pulmonary disease (COPD) are widely documented diseases with an inflammatory component. Asthma is a heterogeneous disorder of the airways that involves chronic inflammation, decline of the airway function and tissue remodeling. Chronic obstructive pulmonary disease is a preventable and treatable disease, which is characterized by persistent limited airflow, and is usually progressive with an increased inflammatory response in the airways. The inflammatory response is evoked by the stimulus of noxious particles and gases. Inflammation is a natural process in response to injury, but in asthma and COPD patients it occurs as an abnormal immune response to pathogenic stimuli which induce chronic inflammation, a key process in the pathogenesis of both diseases. However, the inflammatory process is different in both diseases, and is involved in several release patterns of inflammation mediators. It is not entirely clear whether these proteins are simply markers of the inflammatory process that accompanies a chronic disease or if they play a major role in the pathogenesis of the disease. The main proteins which have been described in these illnesses are: IL-4, IL-6, IL-8, and TNF-α. In addition, polymorphisms have been described in genes encoding these proteins that alter the transcription and susceptibility associated with these diseases. In this review, we will focus on asthma and COPD, and the involvement of these proteins and their genetic polymorphisms.