Role of Apo E and superoxide dismutase in patients with obstructive lung diseases

Abstract

Objective Obstructive lung diseases (OLD) are chronic inflammatory disorders of the respiratory tract including asthma and chronic obstructive pulmonary disease (COPD). Apo lipoprotein E (Apo E) is a multifunctional protein as it intervenes the binding of lipoproteins or lipid complexes to specific cell-surface receptors. Experimental studies referred to the function of Apo E as an endogenous negative regulator of airway hyper responsiveness and goblet cell hyperplasia. The protective role of Apo E pathways primarily in respiratory disease was explained in human studies and research utilizing experimental murine model systems. Literature data reveal a strong association between redox status, including the enzyme superoxide dismutase (SOD) with both the development a severity of OLD. This study aims to investigate the relation between SOD antioxidant enzyme activity in addition to investigating the level of Apo E and the development of obstructive lung diseases (OLD).

Methods Patients with OLD (n = 40) and 40 age-matched healthy controls were enrolled in this study. Serum samples were collected to test the role of Apo E and to test the effect of antioxidant enzyme SOD, and their influence on OLD, all measured by ELISA.

Result The results showed a significant decrease in the level of serum SOD activity in patients with OLD when compared with control group (P < 0.05). However, the levels of Apo E did not show a significant difference between the two groups.

Conclusion Decreased level of antioxidant SOD suggests the presence of an oxidative stress in asthmatic airways favoring a more oxidative state is present in the airway inflammation. The level of Apo E was non significantly increased in serum of patient, this suggests that protein level of Apo E does not change but may be Apo E gene expression is altered.