ABSTRACT
Objective Lipoxin A4 (LXA4) has been proved to have a good protective effect on spinal cord ischemia-reperfusion injury in rats, but whether autophagy is one of the protective mechanisms remains unclear. This study aims to investigate the effects of lipoxin A4 on rat spinal cord ischemia-reperfusion injury. Methods 48 rats were randomly divided into LXA4 group, ischemia-reperfusion group (SCII group) and sham group with 16 rats in each, and the models of each group were built accordingly. The rats in LXA4 group received intrathecal injection of 10μl LXA4 (300 pmol) 30 minutes after clamping the abdominal aorta. Three groups of rats were sacrificed by cervical dislocation 24 hours after reperfusion and the apoptosis-positive cells were then obtained. The spinal cord tissues of three groups of rats were stained and counted by LC3B fluorescence staining, and the expressions of LC3-II/LC3-I and GABARAP protein were detected by Western blot. Results There were few LC3B positive cells in the sham group. Compared to those in the sham group (73.40±19.42), the number of LC3B positive cells in SCII group (399.80±18.46) and LXA4 group (240.80±12.76) significantly increased (P<0.05), and the number in LXA4 group was significantly lower than that in SCII group (P<0.05). The ratio of LC3-II/LC3-I and the expression of GABARAP in SCII group and LXA4 group was significantly higher than those in sham group (P<0.05). The ratio of LC3-II/LC3-I in spinal cord tissue significantly declined compared with that of SCII group (P<0.05). Conclusion The autophagy is activated when SCII occurs, indicating that the autophagy is involved in SCII. After LXA4 is administered, autophagy is inhibited and SCII is alleviated.