Lungs are a pair of cone-shaped organ. It is made up of spongy, pinkish-gray tissues. They occupy large area in the chest and the thorax. The lungs are enveloped in a membrane called pleura. The right lung has three lobes. The left lung has two lobes. In normal individual, at the time of breathing the air enters the body through the nose or the mouth. It then travels down through the larynx and trachea and then goes into the lungs through tubes called bronchi. In the lungs, the main stem bronchi divide into smaller bronchi and then into smaller tubes called bronchioles. At the end of bronchioles air sacs are present which is called as alveoli. Surfactant proteins are small molecules which lines the inner surface …show more content…
COPD is group of conditions with the characteristic of airflow obstruction. The main pathological conditions of COPD are chronic bronchitis which is combination of mucus hyper-secretion and an obstructive ventilator pattern. COPD is characterized by permanent airway obstruction (forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio < 0.7) (Fig.no.2) [21]. Emphysema is the another conditions found in COPD in which air sac of the lungs are damaged and enlarged, causing breathlessness that might play a role in the development of airflow obstruction (Fig.no 3) [22]. Pulmonary function test is primarily used for to confirm the diagnosis of COPD and to measure the airflow obstruction in COPD patients. Forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) are the major parameters in spirometry. The most sensitive indicator for early diagnosis of COPD is decreased ratio of FEV1/FVC …show more content…
It can scavenge 50-75% of reactive radicals such as OH● [55]. Reactive oxygen species induced protein modifications can result in unfolding or alteration of protein structure [56]. Protein reversible modification such as S-glutathionylation, S-nitrosation and methionine sulfoxidation may have dual role of protection from irreversible oxidation and alteration of protein function[57-59]. Protein carbonylation is an irreversible and non-enzymatic reaction. Irreversible protein modification can lead to inactivation of various proteins, loss of their structure and function and could have detrimental effects on the cell. Therefore, protein carbonyl content is the most commonly used marker of protein oxidation[60]. Exposure of gas-phase of cigarette smoke modified human plasma proteins which produces carbonylated proteins with loss of sulfhydryl groups [61]. Recently, Nagai K et reported that the concentration of oxidized proteins in broncho-alveolar lavage fluids were significantly increased in asymptomatic smoker as compared to non-smokers