Oxidant-antioxidant balance in childhood asthma

Background: Asthmatic patients generate reactive oxygen species impairing the antioxidant defense system and creating a state of oxidative stress in asthmatics. Objectives: Determination of the oxidant - antioxidant status in asthmatic children, by measuring the activities of antioxidant enzymes; superoxide dismutases (SOD) and glutathione peroxidases (Gpx) and estimating plasma level of malondialdehyde (MDA) as an index of lipid peroxidation, to find a relation between antioxidant levels and the severity of asthma and the early response to treatment. Methods: This study included 60 children; group (1): 40 asthmatic children and group (2): 20 apparently healthy children as a control group. The following were measured in all the children; plasma level of (MDA), erythrocytes (SOD) and (Gpx) (in asthmatic children two samples were taken; the first during acute attack and the second after 48 hours of treatment). Results: Significant lower erythrocyte antioxidant enzymes activities and higher malondialdehyde was found in asthmatic children compared to the control group, either before or after receiving treatment. In asthmatics, MDA was significantly decreasing and SOD was significantly increasing with treatment. MDA was significantly higher, while SOD was significantly lower with the severity of asthma either before or after receiving treatment. A significant negative correlation was observed between MDA with both of SOD and Gpx, in acute asthmatic attacks. A significant positive correlation was detected between the activities of SOD and Gpx enzymes. Conclusion: Acute asthma leads to a considerable oxidative stress that is indicated by the high level of malondialdehyde and low level of antioxidant enzymes.