Abstract:
Objective To investigate the dose-effect and time-effect expression of histone deacetylase 2(HDAC2) mRNA in B(a)P-induced neural cell apoptosis in vitro.
Methods The primary cultured neurons of rat were assigned into two lots. The first lot was separated into 4 groups and treated with B(a)P at final concentrations as 0 μmol/L(DMSO group), 10 μmol/L (low-dose group), 20 μmol/L(medium-dose group), and 40 μmol/L(high-dose group)respectively, and added S9 at the same time, then incubated for 48 hours. The second lot was separated into 5 groups, all treated with 20 μmol/L B(a)P, then incubated for 0, 6, 12, 24, 48 h respectively. The apoptosis rate of all incubated neurons was detected by flow cytometry, the expression of caspase-3 and HDAC2 mRNA by QRT-PCR.
Results ① Flow cytometry showed that compared with the DMSO group, the apoptosis rates of neurons in middle and high-dose group were significantly increased(P<0.05); compared with the low-dose group, the apoptosis rates also increased(P<0.05). The apoptosis rates at 24, 48 h after exposure were significantly increased compared with that at 0 h(P<0.05). ② The caspase-3 and HDAC2 mRNA expression showed significant increments in highdose group compared with DMSO group(P<0.01). The caspase-3 mRNA expression in high dose group increased significantly compared with the low-dose group(P<0.05). The expressions of caspase-3 and HDAC2 mRNA at 48 h after exposure increased significantly compared with that at 0 h(P<0.01, P<0.05).
Conclusion After exposed to B(a)P, neural cell apoptosis and HDAC2 mRNA expression increased. HDAC2 may play an important role in B(a)P-induced neuronal apoptosis.