Chen Li-yu, Luo Min, Li Tai-cun, Dai Gan, Luo Min-hua
Department of Microbiology, Xiangya School of Medicine, Central South University, Changsha 410078, China.
Zhonghua Er Ke Za Zhi. 2006 Oct;44(10):778-81.
To study the changes of p38MAPK expressions, the frequency of apoptosis and the distribution of cell cycle of hunan Glioma U251 cells after HCMV infection.
The expression of total p38 (both phosphorylated and nonphosphorylated p38) and phosphorylated p38 in U251 cells were detected by Western blotting at 15 min, 30 min, 1 h, 6 h, 10 h, 16 h, 24 h, 36 h and 48 h after HCMV infection. The apoptosis percentage and the cell cycle distribution of U251 cells at 2 d, 5 d and 7 d after HCMV infection were detected by flow cytometry (FCM).
The results of Western blotting demonstrated that a strong increase in phosphorylated p38 was detected from 6 h to 10 h after HCMV infection, with mean gray scales 186.33 +/- 7.51 (t = 5.37, P < 0.01) and 188.00 +/- 7.02 (t = 5.26, P < 0.01 for all) at 6 h and 10 h, respectively, and p38 phosphorylation decreased to the basic level at 16 h after HCMV infection. But the overall levels of p38 protein were not significantly altered during the course of infection. FCM analysis showed that HCMV could significantly increase the apoptotic rates of U251 cells compared with controls (t = 10.84, P < 0.01), and the apoptotic percentages of the cells reached to peak [(10.18 +/- 1.24)%] at 5 d after HCMV infection. The data of FCM showed that HCMV could decrease the number of U251 cells in G1 phase and arrest the cells in S and G2 phase. The numbers of G1 phase U251 cells were significantly lowered to (56.50 +/- 2.57)% (t = 26.45, P < 0.01), (62.33 +/- 2.64)% (t = 21.20, P < 0.01) and (67.45 +/- 4.44)% (t = 10.61, P < 0.01), respectively at 2 d, 5 d and 7 d after infection.
HCMV could activate p38MAPK pathway and trigger apoptosis and interfere cell cycle in U251 cells.
研究人巨细胞病毒（HCMV）感染后人胶质瘤U251细胞中p38丝裂原活化蛋白激酶（p38MAPK）表达的变化、细胞凋亡频率及细胞周期分布。
采用蛋白质免疫印迹法检测HCMV感染后15分钟、30分钟、1小时、6小时、10小时、16小时、24小时、36小时和48小时U251细胞中总p38（磷酸化和非磷酸化p38）及磷酸化p38的表达。采用流式细胞术（FCM）检测HCMV感染后2天、5天和7天U251细胞的凋亡率及细胞周期分布。
蛋白质免疫印迹结果显示，HCMV感染后6小时至10小时磷酸化p38表达显著增加，6小时和10小时的平均灰度值分别为186.33±7.51（t = 5.37，P < 0.01）和188.00±7.02（t = 5.26，P均< 0.01），HCMV感染后16小时p38磷酸化水平降至基础水平。但感染过程中p38蛋白的总体水平无明显变化。FCM分析显示，与对照组相比HCMV可显著增加U251细胞的凋亡率（t = 10.84，P < 0.01），HCMV感染后5天细胞凋亡率达到峰值[（10.18±1.24）%]。FCM数据显示，HCMV可减少G1期U251细胞数量并使细胞停滞于S期和G2期。感染后2天、5天和7天G1期U251细胞数量分别显著降至（56.50±2.57）%（t = 26.45，P < 0.01）、（62.33±2.64）%（t = 21.20，P < 0.01）和（67.45±4.44）%（t = 10.61，P < 0.01）。
HCMV可激活U251细胞中的p38MAPK通路，引发细胞凋亡并干扰细胞周期。
