Objective: To study the feasibility of the transportation of pulmonary surfactant-super oxide dismutase (PS-SOD) liposome to lung tissue in rats.
Methods: 32 Wistar rats were randomly divided into 4 groups (8 rats in each group): normal saline group, PS group, SOD group, PS-SOD liposome group. Each group was further divided into two groups (4 rats in each group), and the rats were respectively killed 2 and 24 hours after the operation. While the biological activity of SOD in irrigating solution and tissue homogenate were detected, lung tissue were labeled with fluorescent and then observed under microscope and transmission electron microscope.
Results: PS-SOD liposome was corps rounds with monolayer lipid with stable surface tension and antioxidative activity. At the point of 2 hours after operation, while the SOD biological activity of irrigating solution in PS-SOD liposome group (32.87 +/- 5.47) and SOD group (33.14 +/- 5.61) were obviously higher than that in normal saline group (2.15 +/- 0.17, P < 0.01), there was no difference between them (P > 0.05). The mean fluorescence optical density in PS-SOD liposome group (0.109 +/- 0.018) was lower than that in normal saline group (0.144 +/- 0.052) and PS group (0.143 +/- 0.026, P < 0.01). 24 hours after operation, the SOD biological activity of irrigating solution in PS-SOD liposome group (11.54 +/- 1.42) was the highest (P < 0.01) and the mean fluorescence optical density in PS-SOD liposome group (0.112 +/- 0.018) was the lowest (P < 0.01). The SOD biological activity of tissue homogenate in PS-SOD liposome group (2 h: 16.83 +/- 2.69, 24 h: 15.70 +/- 2.75) was higher than that in normal saline group (2 h: 5.79 +/- 0.93, 24 h: 5.84 +/- 1.31) and in SOD group (2 h: 7.07 +/- 1.04, 24 h: 6.11 +/- 1.06, P < 0.01) both at the point of 2 and 24 hours after the operation. Lots of PS-SOD liposome was observed in type II alveolar epithelial cells under transmission electron microscope.
Conclusion: Intrathecal administ ration of PS-SOD liposome enhanced the transportation of SOD into lung tissue and its antioxidative activity.