Expression of Foxo3a and p27kip1 in lumbar dorsal root ganglia (DRG) after rat sciatic nerve injury / 中华显微外科杂志

ABSTRACT

Objective To investigate the expression of Foxo3a and p27kip1 in lumbar dorsal root ganglia (DRG) after injury of sciatic nerve in rats. Methods Adult rats were randomly divided into control group and experimental group. The rats in experimental group were subjected to sciatic nerve clamp.Expression and distribution of Foxo3a and p27kip1 and cellular proliferation and axon regeneration in DRG was detected by western blot and immunohistochemistry. Results Foxo3a protein levels begined to reduce at 1 day (7.0 ± 3.5), reached valley at 2 day (6.0 ± 3.8) after injury, and following Foxo3a downregulation, p27kip1 protein levels begined to decrease at 2 day (29.0 ± 3.5), reached valley at 7 day (21.0± 3.0) after injury. Down-regulation of Foxo3a and p27kip1 was expressed predominantly in neurons and glial cells by double immunolabelling. Foxo3a and p27kip1 were expressed in neurons [(37.8 ± 5.7)%, (43.3 ±4.3)%] and glial [(22.4 ± 3.9)%, (13.8 ± 3.2)%] cells in sections of DRG at 2 day after injury less than neurons [(73.6 ± 2.5)%, (84.1 ± 3.7)%] and glial [(61.3 ± 4.4)%, (68.7 ± 5.6)%] cells in sections of normal DRG. Proliferating cell nuclear antigen (PCNA) and GAP-43 were up-regulation from 2 day, and PCNA reached peak at 7 day after injury.The glial cells were the main type of cellular proliferation.Conclusion Down-regulation of Foxo3a and p27kip1 in lumbar DRG is correlated with the proliferation of glial cells and axonal regeneration after sciatic nerve injury.