Autophagy dysregulation, mitochondrial dynamic abnormality and cell cycle re-entry are implicated in the vulnerable neurons of patients with Alzheimer＇s disease. This study was designed to testify the association amo...Autophagy dysregulation, mitochondrial dynamic abnormality and cell cycle re-entry are implicated in the vulnerable neurons of patients with Alzheimer＇s disease. This study was designed to testify the association among autophagy, mitochondrial dynamics and cell cycle in dividing neuroblas- toma （N2a） cells. The N2a cells were cultured in vitro and treated with different concentrations of 3-methyladenine （3-MA）. The cell viability was detected by methyl thiazolyl tetrazolium （MTT） assay. They were randomly divided into control group （cells cultured in normal culture medium） and 3-MA group （cells treated with 10 mmol/L 3-MA）. The cell cycle was analyzed in the two groups 3, 6, 12, and 24 h after treatment by flow cytometry. Western blotting was used to evaluate the expression levels of mitofission 1 （Fisl）, mitofusin 2 （Mfn2）, microtubule-associated protein 1 light chain 3 （LC3）, cell cy- cle-dependent kinase 4 （CDK4） and cdc2. The flow cytometry revealed that the proportion of cells in G2/IVI was significantly increased, and that in G0/G1 was significantly reduced in the 3-MA group as compared with the control group. Western blotting showed that the expression levels of Fisl, LC3, and CDK4 were significantly up-regulated in the 3-MA group at the four indicated time points as compared with the control group. Mfn2 was initially decreased in the 3-MA group, and then significantly in- creased at 6 h or 12 h. Cdc2 was significantly increased in the 3-MA group at 3 h and 6 h, and then dropped significantly at 12 h and 24 h. Our data indicated that 3-MA-induced suppressed autophagy may interfere with the cell cycle progression and mitochondrial dynamics, and cause cell death. There are interactions among cell cycle, mitochondrial dynamics and autophagy in neurons.展开更多
基金supported by a grant from the Specialized Research Fund for the Doctoral Program of Education Ministry of China(No.20100142110032)
文摘Autophagy dysregulation, mitochondrial dynamic abnormality and cell cycle re-entry are implicated in the vulnerable neurons of patients with Alzheimer＇s disease. This study was designed to testify the association among autophagy, mitochondrial dynamics and cell cycle in dividing neuroblas- toma （N2a） cells. The N2a cells were cultured in vitro and treated with different concentrations of 3-methyladenine （3-MA）. The cell viability was detected by methyl thiazolyl tetrazolium （MTT） assay. They were randomly divided into control group （cells cultured in normal culture medium） and 3-MA group （cells treated with 10 mmol/L 3-MA）. The cell cycle was analyzed in the two groups 3, 6, 12, and 24 h after treatment by flow cytometry. Western blotting was used to evaluate the expression levels of mitofission 1 （Fisl）, mitofusin 2 （Mfn2）, microtubule-associated protein 1 light chain 3 （LC3）, cell cy- cle-dependent kinase 4 （CDK4） and cdc2. The flow cytometry revealed that the proportion of cells in G2/IVI was significantly increased, and that in G0/G1 was significantly reduced in the 3-MA group as compared with the control group. Western blotting showed that the expression levels of Fisl, LC3, and CDK4 were significantly up-regulated in the 3-MA group at the four indicated time points as compared with the control group. Mfn2 was initially decreased in the 3-MA group, and then significantly in- creased at 6 h or 12 h. Cdc2 was significantly increased in the 3-MA group at 3 h and 6 h, and then dropped significantly at 12 h and 24 h. Our data indicated that 3-MA-induced suppressed autophagy may interfere with the cell cycle progression and mitochondrial dynamics, and cause cell death. There are interactions among cell cycle, mitochondrial dynamics and autophagy in neurons.
