The effects of ginsenoside on nerve cell apoptosis and neurogenesis after spinal cord injury in rats and the related mechanisms

Objective To investigate the effect and related mechanisms of total ginsenoside on promoting endogenous neural stem cell proliferation and inhibiting neural cell apoptosis after spinal cord injury in rats.Methods One hundred SD rats were randomly divided into five groups:sham operation group,spinal cord injury group,total ginsenoside treatment group,RU-486 antagonist groups,and RU-486 treatment group.Behavioral tests were conducted at 1,3,7 and 14 days after the injury.Slope angle and Basso,Beattie and Bmsnahan (BBB) locomotor scores were recorded to evaluate restoration of function.Spinal cord samples were harvested 5 mm proximal and distal to the injury site at 14 days of the injury.BrdU and Nestin positive cells were detected using Nissl staining and immunofluomscence staining.Apoptotic cells were determined using the Tunel kit.Results In the slope experiment and the BBB locomotor rating experiment,the ginsenoside treatment group scored significantly higher than the spinal cord injury group and RU-486 treatmem group.Compared to the spinal cord injury group,the ginsenoside treatment group had significantly higher number of BrdU positive cells and Nestin positive cells.The number of apoptotic cells was significantly reduced.RU-486 antagonist group had fewer BrdU positive cells and Nestin positive cells and more apoptotic cells than the ginsenoside treatment group.On the other hand RU-486 treatment group showed no significant difference in the number of apoptotic cells compared to the injury group.Conclusion Ginsenoside can promote the recovery of neurological function in spinal cord injury rats and can inhibit neuronal apoptosis. Key words: Spinal cord injury;  Rats;  Panax ginseng;  Neural stem cells;  BrdU;  Nestin