BACKGROUND:Apoptosis and autophagy imbalance in the hippocampal region of perimenopausal depressed rats are closely related to cognitive decline.Whether aerobic exercise can reduce apoptosis by promoting hippocampal autophagy and thus improve the learning and memory abilities of perimenopausal depressed rats is not clear.OBJECTIVE:To investigate the possible mechanism by which 4-week moderate-intensity treadmill exercise improves learning memory ability in ovariectomized stressed rats.METHODS:Forty Sprague-Dawely rats were randomly divided into four groups,namely,sham operation group(n=10),ovariectomized group(n=10),ovariectomized stress group(n=10)and ovariectomized stress exercise group(n=10).Except for the sham operation group,the ovaries were removed in the other three groups to establish a perimenopausal rat model,and then a depressed rat model was established by chronic unpredictable stress in the latter two groups.The rats in the ovariectomized stress exercise group underwent a 4-week moderate-intensity treadmill exercise.Tail suspension test and sucrose preference test were performed to text depression-like behaviors in rats after exercise and stress.The eight-arm maze experiment was used to test the learning and memory behaviors of rats after exercise and stress.Western blot was used to detect the protein levels of AMP-activated protein kinase/UNC-51 like autophagy activating kinase 1/mammalian target of rapamycin(AMPK/mTOR/ULK1),hippocampus apoptotic factor Caspase-3 and the protein expression of autophagy markers LC-3II/Beclin-1 in the hippocampus.RESULTS AND CONCLUSION:(1)Compared with the sham operation group,rats in the ovariectomized and ovariectomized stress groups had prolonged resting time in the tail suspension test and decreased sugar-water intake and sugar-water preference in the sucrose preference test.(2)Ovary removal reduced the learning memory capacity of rats,as evidenced behaviorally by a significant increase in the number of working memory errors,the number of reference memory errors,and the completion time,and an even more pronounced increase in the above measures in the ovariectomized stress group.(3)Compared with the ovariectomized group,there was a significant reduction in the number of working memory errors,the number of reference memory errors,and the completion time in the ovariectomized stress group.(4)Compared with the sham operation group,in the ovariectomized and ovariectomized stress groups,the expression of hippocampal apoptotic factor Caspase 3 protein was significantly elevated,the expression of autophagy-related factors proteins Beclin-1 and LC3II,as well as the protein expression of AMPK and ULK1,was decreased,whereas the expression of mTOR protein was elevated.Changes in the above indicators were more significant in the ovariectomized stress group.(5)Compared with the ovariectomized stress group,in the ovariectomized stress exercise group,the protein expression of Caspase 3 was significantly decreased,the protein expression of Beclin-1 and LC3II was significantly increased,the protein expression of AMPK and ULK1 was significantly increased,and the protein expression of mTOR was significantly reduced.To conclude,4-week moderate-intensity treadmill exercise may promote cellular autophagy and reduce apoptosis through the AMPK/mTOR/ULK1 autophagy signaling pathway,thereby enhancing the learning and memory capacity of rats with ovariectomized depression

BACKGROUND:Apoptosis and autophagy imbalance in the hippocampal region of perimenopausal depressed rats are closely related to cognitive decline.Whether aerobic exercise can reduce apoptosis by promoting hippocampal autophagy and thus improve the learning and memory abilities of perimenopausal depressed rats is not clear.OBJECTIVE:To investigate the possible mechanism by which 4-week moderate-intensity treadmill exercise improves learning memory ability in ovariectomized stressed rats.METHODS:Forty Sprague-Dawely rats were randomly divided into four groups,namely,sham operation group(n=10),ovariectomized group(n=10),ovariectomized stress group(n=10)and ovariectomized stress exercise group(n=10).Except for the sham operation group,the ovaries were removed in the other three groups to establish a perimenopausal rat model,and then a depressed rat model was established by chronic unpredictable stress in the latter two groups.The rats in the ovariectomized stress exercise group underwent a 4-week moderate-intensity treadmill exercise.Tail suspension test and sucrose preference test were performed to text depression-like behaviors in rats after exercise and stress.The eight-arm maze experiment was used to test the learning and memory behaviors of rats after exercise and stress.Western blot was used to detect the protein levels of AMP-activated protein kinase/UNC-51 like autophagy activating kinase 1/mammalian target of rapamycin(AMPK/mTOR/ULK1),hippocampus apoptotic factor Caspase-3 and the protein expression of autophagy markers LC-3II/Beclin-1 in the hippocampus.RESULTS AND CONCLUSION:(1)Compared with the sham operation group,rats in the ovariectomized and ovariectomized stress groups had prolonged resting time in the tail suspension test and decreased sugar-water intake and sugar-water preference in the sucrose preference test.(2)Ovary removal reduced the learning memory capacity of rats,as evidenced behaviorally by a significant increase in the number of working memory errors,the number of reference memory errors,and the completion time,and an even more pronounced increase in the above measures in the ovariectomized stress group.(3)Compared with the ovariectomized group,there was a significant reduction in the number of working memory errors,the number of reference memory errors,and the completion time in the ovariectomized stress group.(4)Compared with the sham operation group,in the ovariectomized and ovariectomized stress groups,the expression of hippocampal apoptotic factor Caspase 3 protein was significantly elevated,the expression of autophagy-related factors proteins Beclin-1 and LC3II,as well as the protein expression of AMPK and ULK1,was decreased,whereas the expression of mTOR protein was elevated.Changes in the above indicators were more significant in the ovariectomized stress group.(5)Compared with the ovariectomized stress group,in the ovariectomized stress exercise group,the protein expression of Caspase 3 was significantly decreased,the protein expression of Beclin-1 and LC3II was significantly increased,the protein expression of AMPK and ULK1 was significantly increased,and the protein expression of mTOR was significantly reduced.To conclude,4-week moderate-intensity treadmill exercise may promote cellular autophagy and reduce apoptosis through the AMPK/mTOR/ULK1 autophagy signaling pathway,thereby enhancing the learning and memory capacity of rats with ovariectomized depression

Objective:To identify potential risk factors of suicide among schizophrenic inpatients,in order to provide basis of how to prevent suicide in psychiatric inpatients.Method:A retrospective analysis among inpatients with mental disorders in Guangzhou psychiatric hospital from 1956 to 2005,the first psychiatric hospital,in China.Using a case-control design,sixty four schizophrenic inpatients(suicide group) who committed suicide in psychiatric hospital and the same number of randomly selected control subjects(control group) who had no incident of suicide were selected and their psychiatric records were compared.Results:The rate of suicide was 133.1(95% CI 103.4-62.9) per 100 000 admissions.Sixty four cases(83.1%) were diagnosed as schizophrenia,fifty nine(76.6%) were hung by themselves,and fifty two(67.5%) happened in wards.The numbers of hospitalization and the suicide attempts before and duration of hospitalization were significantly higher in suicide group than that in control group(P=0.001,0.017,0.003),and guilty thoughts,depressive mood were significantly higher in suicide group than that in control group(P=0.006,0.004).Both suicidal ideation and suicide attempts one month before and during hospitalization were significantly higher in suicide group than that in control group(P