ABSTRACT
AIM:To investigate the effects of ginsenoside Rg1 on the behavioral changes and the autophagy of hippocampal neurons of the rats with post-traumatic stress disorder (PTSD).METHODS:The Sprague-Dawley rats were randomly divided into 5 groups:control group, model group, fluoxetine group, low-dose ginsenoside Rg1 group and high-dose of ginsenoside Rg1 group.The combination of single prolonged stress and foot stock was performed to induce PTSD-like animal model.The rats in fluoxetine group was administered with fluoxetine by gavage at dose of 10 mg/kg for 21 d, while the rats in low and high doses of ginsenoside Rg1 groups were administered with ginsenoside Rg1 by gavage at doses of 20 mg/kg and 40 mg/kg for 21 d, respectively.The rats in control group and model group were both given saline by gavage for 21 d.The open-field test and stiff behavior test were used to examine the behavioral changes of the rats.The morphological structure and numerical changes of the hippocampal neurons were observed by Nissl-staining method.We adopted immunofluorescence labeling to observe the beclin 1 and LC3 positive hippocampal neurons and the levels of beclin 1 and LC3-Ⅱ/LC3-Ⅰratio in rat hippocampus.RESULTS:Compared with control group, decreased vertical movement time and horizontal movement time in open-field test and increased rate of stiff behavior in the stiff behavior test were observed in model group.Hippocampal neurons in model group were loosely arranged with vacuole-like structures and different degrees of cell shrinkage in contrast with control group.More beclin 1 and LC3 positive cells were identified, and higher protein levels of beclin 1 and ratio of LC3-Ⅱ/LC3-Ⅰ in model group were found as compared with control group.However, increase in movement in open-field test and decrease in stiff behavior were detected in the rats treated with low-and high-dose ginsenoside Rg1 as compared with the model rats.Meanwhile, vacuole structures, the numbers of beclin 1 and LC3 positive neurons, the protein expression of beclin 1 and LC3, and the total cell numbers were increased.Higher dose of ginsenoside Rg1 had more profound effects on these observed results.CONCLUSION:Ginsenoside Rg1 alleviates the abnormal behaviors in the PTSD rats, which might be related to the inhibition of abnormal autophagy of hippocampal neurons.