三羟基异黄酮对APP695基因转染PC12细胞Bax和Bcl-2蛋白表达的影响

Effect of genistein on the expression of Bax and Bcl-2 protein in PC12 cells transfected with mutant APP695 type

目的观察植物雌激素三羟基异黄酮（genistein，GST）对APP695基因转染PCI2细胞Bax和Bcl-2蛋白表达的影响。方法用pIRES2-EGFP空载体和pIRES2-EGFP／APP695MT表达载体转染正常PCI2细胞，将细胞分为正常对照组、空载转染组、APP695转染组和GST干预组（5tLmol／L、15Ixmol／L）。采用免疫细胞化学SABC法和免疫印迹法检测凋亡相关蛋白Bax和Bcl-2在PCI2细胞中的表达。结果免疫细胞化学SABC法结果显示，与正常对照组比较，APP695转染组PCI2细胞Bax蛋白细胞阳性表达率显著升高[（78．02±1．26）％，P〈0．01）]，Bcl-2蛋白细胞阳性表达率则明显降低[（15．40±0．72）％，P〈0．01）]；15~mol／LGST组与APP695转染组比较，Bax蛋白的阳性细胞表达率显著降低[（22．35±0．49）％，P〈0．01）]，而Bcl-2蛋白的阳性表达率明显增强[（68．11±0．24）％，P〈0．01）]。Westernblot结果表明，APP695转染组与对照组比较Bax蛋白的表达量明显增多，Bcl-2蛋白表达则明显降低；GST各处理组与APP695转染组比较，Bax蛋白的表达量明显降低，Bcl-2蛋白表达显著增强。结论GST能降低APP695基因转染引起的PCI2细胞内Bax蛋白表达的水平，而提高Bcl-2蛋白的表达水平，对PCI2细胞产生保护作用。

Objecti±e To in±estigate the effect of genistein on the expression of Bax and Bcl-2 protein in PC12 cells transfected with mutant APP695 Type. Methods PC12 cells were transfected with pIRES2-EGFP plasmid or pIRES2-EGFP/APP695MT expression plasmid, and then di±ided into normal control group, Unladen group,APP695 transfected group,GST treatment group（5 μmol/L, 15 μmol/L）. The Bax and Bcl-2 protein ex- pression in PC12 cells was measured by Immunocytochemistry SABC and Western-blot. Results Immunocytochemistry SABC showed that：compared with the normal control group, the expression of bax protein in APP695 transfected group was strongly increased（ （78.02 ± 1.26） % , P 〈 0.01 ） ） and the expression of bcl-2 protein was ±ery weak oppositely （ （ 15.40 ± 0.72 ） % , P 〈 0.01 ） ）. Compared with APP695 transfected group, the expression of bax protein in cells of 15umol/L GST treatment group was significantly decreased （ （22.35 ± 0.49）% , P 〈 0. 01 ） ） and the expression of bcl-2 protein in these cells was strongly increased （ （68.11 ±0.24）%, P〈0.01 ） ）. West- ern-Blot showed that：compared with the normal control group,the expression of bax protein in APP695 transfected group was markedly increased and the expression of Bcl-2 protein was significantly decreased. Compared with the APP695 transfected group,the expression of Bax protein was markedly decreased and the expression of Bcl-2 pro- tein was significantly increased in the cells of the GST treatment groups. Conclusion GST can reduce the expres- sion of bax protein and the increased expression of Bcl-2 protein has protecti±e effect on PC12 cells transfected with APP696MT.