Objective:To study the effect of baicalein on the expression of glutamate receptor related protein in PC12 cells injured by Aβ 25-35. Methods:PC12 cells were divided into control group, model group, estradiol group and baicalein group with different concentrations. The survival condition of PC12 cells in each group were detected by thiazole blue (MTT). PC12 cells were divided into control group, model group, estradiol group and baicalein group. The control group and model group were cultured with DMEM medium, and the estradiol group was added with 1×10 -3 μmol/L estradiol DMEM medium, baicalein group was added with 1 μmol/L baicalein DMEM medium. After 2 hours of intervention, 20 μmol/L Aβ 25-35 was added to the model group, estradiol group and baicalein group with induced PC12 cell injury. After 22 hours of intervention, flow cytometry was used to detect the apoptosis of PC12 cells. The expression of estrogen receptor β (ER β), phosphorylated c-Jun N-terminal kinase (p-JNK/JNK) and ionic receptor N-methyl-D-aspartate receptor 1 (NMDAR1), glutamate receptor 2 (GluR2) and calcium/calmodulin dependent protein kinase Ⅱ (CaMK Ⅱ) were detected by Western blot. Results:Compared with model group, 1 μmol/L baicalein significantly increased the proliferation rate [(95.80±2.47)% vs. (64.34±3.84)%]. The apoptosis rate of PC12 cells[(7.83±0.67)% vs. (12.84±0.91)%] was significantly decreased in baicalein group ( P<0.01). The expression of NMDAR1 (0.582±0.012 vs. 0.352±0.012), GluR2(0.538±0.017 vs. 0.355±0.006), ER β (0.362±0.015 vs. 0.262±0.018) in baicalein group were significantly increased ( P<0.01), the expression of p-JNK/JNK (0.476±0.013 vs. 0.752±0.014) and CaMK Ⅱ(0.499±0.019 vs. 0.670±0.016) in baicalein group were significantly decreased ( P<0.01). Conclusions:Baicalein has a protective effect on PC12 cells injured by Aβ 25-35. Its mechanism may be related to the inhibition of p-JNK/JNK activity by activating ERβ and regulating the expression of glutamate receptor related protein.

Objective:To investigate the effects of down-regulation of FABP5 (fatty acid binding protein 5) on radiation damage of skin cells, and explore underlying mechanism.Methods:A lentiviral vector with down-regulated FABP5 was constructed to infect human immortalized keratinocytes (HaCaT) cells, and the transfection efficiency was examined. The HaCaT cells were divided into blank control group, FABP5 down-regulation group (FABP5), radiation group (IR), and FABP5 down-regulation combined with radiation group (FABP5+ IR). After 6 MV X-ray radiation, cell proliferation viability was measured by CCK-8 assay, cell migration was detected by scratch assay, apoptosis was analyzed by flow cytometry, radiosensitivity was evaluated by cloning formation assay, and the cellular protein expressions of PARP1, γ-H2AX, AKT and p-AKT were detected by Western blot.Results:FABP5 was successfully knocked-down in both RNA level ( t=25.14, P<0.05) and protein level ( t=20.06, P<0.05). The down-regulation of FABP5 decreased the abilities of cells proliferation ( t=3.55, 5.88, 3.18, P<0.05) and migration ( t=15.44, P<0.05), but increased cell resistance to irradiation with a radiosensitization ratio of 0.782. The apoptosis rate of FABP5+ IR group was significantly lower than IR group (22.05±6.71)% vs. (9.82±1.45)%, t=3.08, P<0.05. The protein levels of PARP1 and γ-H2AX in FABP5+ IR group were also lower than those in the IR group 0.04±0.04, 0.11±0.06, 0.26±0.11, 0.22±0.07, 0.21±0.10, 0.52±0.22, 0.57±0.06, 0.43±0.02( t=2.83, 3.07, 4.50, 5.33, P<0.05), while the protein level of p-Akt in FABP5+ IR group was higher than that in IR group ( t=-16.24—3.02, P<0.05). Conclusions:Down-regulation of FABP5 inhibited cell proliferation and migration, increased radioresistance, and reduced radiation-induced apoptosis and DNA damage of skin cells probably through PI3K/AKT signaling pathway.