Role of Apoptosis in Acute Lung Injury

Abstract

The present• study was carried out on 49 mechanically ventilated patients in the ICU of Assiut University Hospital. (27 cases of acute respiratory distress syndrome and 22 cases of acute lung injury). Also, 17 apparently healthy patients were included as a control group. Patients with ARDS were defined by refractory hypoxemia, non-cardiogenic pulmonary oedema, bilateral pulmonary infiltrates, decreased lung .compliance and normal pulmonary capillary wedge pressure. All cases and control group were thoroughly examined. Patients were subjected to complete clinical assessment including demographic information, routine laboratory measurements ( kidney function tests, blood sugar level, plain chest-X ray, blood picture and blood gases). For patients and control group, blood level of caspase-3 and serum levels of Fas antigen, lipid peroxides, superoxide dismutase (SOD) enzyme activity and total thiols were assessed.

• The serum level of Fas as well as caspase-3 in ALI and ARDS patients were found to be significantly higher than the corresponding

levels in controls.

During follow up period of our patients no significant change in Fas level was noticed, while caspase-3 level was significantly decreased on the 3"' day compared to the corresponding level on admission and on the 7th day. Thus, the main role of Fas in the lung inflammatory response might contribute to sustain inflammation. The caspase-3 was found to be a crucial mediators of programmed cell death, which frequently activated death proteases.