Protective effect of bone marrow mesenchymal stem cells on PC12 cells apoptosis mediated by TAG1.

OBJECTIVE This study aims to explore the protection effect of bone marrow mesenchymal stem cells (BMSCs) on PC12 cells apoptosis mediated by transient axonal glycoprotein 1 (TAG1). METHODS PC12 cells were divided into control group, Aβ25-35 group and BMSCs + Aβ25-35 group. The effects of BMSCs on PC12 cells treated by Aβ25-35 were detected using MTT, Hoechst 33258 and Annexin V-FITC/PI staining methods. The expression levels of TAG1, β-amyloid precursor protein (APP), AICD and p53 were determined by RT-PCR and Western blotting methods. The expression levels of Bax and Bcl-2 were determined by Western blotting method. The activity of Caspase 3 was detected by spectrophotometric method. RESULTS MTT results showed that cell activity decreased after the treatment of 20 μM Aβ25-35 for 48 h (P<0.01) while it increased in BMSCs + Aβ25-35 group (P<0.01). Hoechst 33258 and Annexin V-FITC/PI staining results showed that Aβ25-35 could induce the apoptosis of PC12 cells while the apoptosis of PC12 cells was inhibited in BMSCs + Aβ25-35 group. RT-PCR and Western blotting methods showed that 20 μM Aβ25-35 could increase the expression levels of TAG1, APP, AICD and p53 (P<0.01) while they decreased in BMSCs + Aβ25-35 group (P<0.01). 20 μM Aβ25-35 could increase the expression levels of Bax and decrease the expression levels of Bcl-2 (P<0.01), while the expression levels of Bax decreased and the expression levels of Bcl-2 increase in BMSCs + Aβ25-35 group (P<0.01). 20 μM Aβ25-35 could enhance Caspase 3 activity while it decreased in BMSCs + Aβ25-35 group (P<0.01). Conclusions BMSCs with Aβ25-35 could inhibit the apoptosis of PC12 cells, which maybe related with TAG1/APP/AICD signal pathway.