摘要
Objective To investigate the neuroprotective effects and the mechanism of this protection of raloxifene （RLX）, a selective estrogen receptor modulator.Methods MTT assay and flow cytometry with annexin V-FITC/PI staining were performed to evaluate the neuroprotective effects of RLX on Aβ25-35-induced toxicity. The potential mechanisms were studied by Western blotting in cultured rat pheochromocytoma cells （PC12 cells）.Results RLX（1 000 nmol/L）, in combination with Aβ25-35 （30 llmol/L）, increased the cell viability （P 〈0.001）, and reduced the number of apoptotic cells （P 〈0.05）. RLX attenuated Aβ25-35-induced loss of △ψm （P 〈0.01）. The changing of △ψm was similar to the variation of apoptosis. PD98059 （inhibitor of ERK1/2） inhibited the effects of RLX on cell viability and phosphorylation of cleaved caspase-9. No significant difference of cell viability or phosphorylation of cleaved caspase-9 had been found when PC12 cells were incubated with SB203580 （inhibitor of p38MAPK） or SP600125 （inhibitor of JNK）. Afl25.35 induced a time-dependent phosphorylation of p38MAPK and JNK. In PC12 cells treated solely with RLX, ERK1/2 was activated （P〈0.01）. In PC12 cells treated with Aβ25-35 and RLX, Aβ2545-induced phosphorylation of p38MAPK and JNK were inhibited （P〈0.01 and P〈0.001, respectively）.Conclusion RLX inhibited Af125.35-induced cell apoptosis by activating the ERK1/2 pathway in PC12 cells. RLX also attenuated Aβ25-35-induced activation of p38MAPK and JNK. The mitochondria pathway Was involved in this inhibitory effect.
Objective To investigate the neuroprotective effects and the mechanism of this protection of raloxifene （RLX）, a selective estrogen receptor modulator.Methods MTT assay and flow cytometry with annexin V-FITC/PI staining were performed to evaluate the neuroprotective effects of RLX on Aβ25-35-induced toxicity. The potential mechanisms were studied by Western blotting in cultured rat pheochromocytoma cells （PC12 cells）.Results RLX（1 000 nmol/L）, in combination with Aβ25-35 （30 llmol/L）, increased the cell viability （P 〈0.001）, and reduced the number of apoptotic cells （P 〈0.05）. RLX attenuated Aβ25-35-induced loss of △ψm （P 〈0.01）. The changing of △ψm was similar to the variation of apoptosis. PD98059 （inhibitor of ERK1/2） inhibited the effects of RLX on cell viability and phosphorylation of cleaved caspase-9. No significant difference of cell viability or phosphorylation of cleaved caspase-9 had been found when PC12 cells were incubated with SB203580 （inhibitor of p38MAPK） or SP600125 （inhibitor of JNK）. Afl25.35 induced a time-dependent phosphorylation of p38MAPK and JNK. In PC12 cells treated solely with RLX, ERK1/2 was activated （P〈0.01）. In PC12 cells treated with Aβ25-35 and RLX, Aβ2545-induced phosphorylation of p38MAPK and JNK were inhibited （P〈0.01 and P〈0.001, respectively）.Conclusion RLX inhibited Af125.35-induced cell apoptosis by activating the ERK1/2 pathway in PC12 cells. RLX also attenuated Aβ25-35-induced activation of p38MAPK and JNK. The mitochondria pathway Was involved in this inhibitory effect.
基金
supported by the "Six Talents Peak" of Jiangsu Province,China 973 Program(No.2007CB944005)
Science and Technology Development Foundation of Nanjing Medical University(No.2011NJMU152)
