Inhibition of Toll-like receptor 9 activation in microglia after oxygen-glucose deprivation and reoxygenation protects neurons from damage
PENG Qing-xia1, YANG Bi-ying2, PAN Jing-rui1, WANG Hong-xuan1, LI Xiang-pen1, WANG Yi-dong1
1. Department of Neurology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China;
2. The Forth Department of Neurology, Guangdong Provincial Hospital of Traditional Chinese Medicine, Guangzhou 510120, China
AIM: To observe the Toll-like receptor 9 (TLR9) activation in microglia BV-2 cells after oxygen-glucose deprivation and reoxygenation (OGDR), and its effects on neuronal apoptosis. METHODS: The BV-2 cell supernatants were collected after the corresponding treatment and added to mouse primary cortical neurons after OGDR for 4 h, followed by normal culture for 24 h. The cells were divided into normal BV-2 group, NC-siRNA group, TLR9-siRNA group, OGDR group, OGDR+NC-siRNA group, OGDR+TLR9-siRNA group and control group (without adding BV-2 cell supernatant). The changes of the neuronal morphology were observed under an inverted phase- contrast microscope, and the neuronal apoptosis was detected by TUNEL. The protein expression of cleaved caspase-3 was detected by Western blotting. RESULTS: After OGDR, the axon turned thin, twisted and broken, and neuronal swelling, decrease in refraction and vacuolar degeneration were observed. The green-stained apoptotic bodies in the neurons in all groups were positive. Compared with control group, the caspase-3 protein levels in other groups were increased. Compared with the normal BV-2 group, the caspase-3 protein in OGDR group and TLR9-siRNA group was increased. Compared with OGDR+TLR9-siRNA group, the caspase-3 protein in TLR9-siRNA group and OGDR group was decreased. CONCLUSION: After OGDR, TLR9 activation in BV-2 cells induces neuronal apoptosis with the increase in caspase-3 protein level. Inhibition of TLR9 expression reduces neuronal damage.
彭晴霞, 杨碧莹, 潘经锐, 王鸿轩, 黎祥喷, 王艺东. 氧葡萄糖剥夺－再恢复后抑制小胶质细胞TLR9激活对神经元的保护作用[J]. 中国病理生理杂志, 2015, 31(3): 403-408.
PENG Qing-xia, YANG Bi-ying, PAN Jing-rui, WANG Hong-xuan, LI Xiang-pen, WANG Yi-dong. Inhibition of Toll-like receptor 9 activation in microglia after oxygen-glucose deprivation and reoxygenation protects neurons from damage. Chin J Pathophysiol, 2015, 31(3): 403-408.
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