Curcumin improved mitochondrial function of N2a/APP695swe cells and inhibited apoptosis

Abstract:

Objective：To observe the effects of curcumin on the mitochondrial morphology and functions，and on the apoptosis in N2a/APP695swe cells，and to explore the underlying mechanisms. Methods：The experimental cells were divided into four groups：N2a/APP695 group（WT），N2a/APP695swe group（APP），dissolvent control group（DMSO，5 μmol/L） and Curcumin group（5 μmol/L）. Flow cytometry（FCM） method was used to investigate apoptosis，the level of cytosolic ROS and the change of mitochondrial membrane potential. Immunocytochemistry technique was performed to analyze changes of cytochrome C in experimental cells. The morphology of mitochondria was observed by electron microscope. Western blot was carried out to detect the expression of caspase3 and caspase9 protein. And the activities of caspase3 and caspase9 were assessed by spectrophotometry. Results：Apoptosis and cytosolic ROS were significantly lower in the curcumin group than in the APP group（0.05±0.01 vs. 0.18±0.01，P=0.000；49.67±4.16 vs. 197.67±8.08，P=0.000），and the mitochondrial membrane potential was higher in the curcumin group than in the APP group（1.00±0.03 vs. 0.64±0.03，P=0.000）. The electron microscopy found that curcumin could reduce the swelling of the mitochondria and improve its shape. Furthermore，curcumin could reduce the release of cytochrome C and the expression of caspase3 and caspase9 protein in the curcumin group than in the APP group（0.62±0.12 vs. 1.39±0.10，P=0.000；0.64±0.20 vs. 1.78±0.03，P=0.000）. Similarly，the activity of caspase3 and caspase9 was significantly lower in the curcumin group than in the APP group（0.66±0.04 vs. 2.12±0.06，P=0.000；0.58±0.04 vs. 0.93±0.03，P=0.000）. Conclusions：Curcumin could reduce the apoptosis of the N2a/APP695swe cell，and its mechanism may be associated with improved mitochondrial function.