Pigment epithelium-derived factor may play a role in apoptosis of human liver cells induced by arsenic through regulating Bcl-2 level / 中华地方病学杂志

ABSTRACT

Objective To explore the mechanism of pigment epithelium-derived factor (PEDF) on human liver cells in mitochondrial apoptosis induced by arsenic. Methods Human normal liver cell line (HHL-5) was exposed to NaAsO2 for 24 h, the dose was 0 (control), 2, 5, 8 and 10 μmol/L, respectively. The mitochondrial membrane potential was determined by using flow cytometry, and mRNA levels of PEDF, Bcl-2 and Bax were assayed by Real-time fluorescent quantitative PCR. Results The mitochondrial membrane potential in 10 μmol/L arsenic group (562.33 ± 31.50) was decreased markedly in comparison with that of control group (688.67 ± 47.50, P<0.01), the levels in other groups (5 μmol/L: 634.50 ± 49.03, 8 μmol/L: 655.67 ± 13.65) were not significantly changed (P > 0.05). Compared with control group [(86.69 ± 12.19)％], the mRNA levels of PEDF decreased significantly (P<0.01) when the HHL-5 cells were cultivated with 5 μmol/L [(59.35 ± 11.21)％], 8μmol/L [(58.46 ± 8.69)％] and 10μmol/L [(51.57 ± 7.58)％] arsenic, respectively, and the PEDF mRNA level in 10 μmol/L group was the lowest; but there was no significant change in PEDF mRNA level [(81.52 ± 13.93)％] when HHL-5 cell was cultivated with 2μmol/L arsenic. Similarly, mRNA level of Bcl-2 in 10 μmol/L arsenic group [(53.53 ± 21 . 49 )％] was significantly decreased compared with that of the control group [(96.48 ± 31.14)％, P < 0.05]. Whereas, Bax mRNA levels in arsenic exposure groups [(65.14 ± 32.34)％, (71.81 ± 12.61)％, (72.22 ± 28.40)％] were not significantly changed in comparison with that of control group [(84.47 ± 35.38)％, P > 0.05]. Conclusion PEDF may play a role in mitochondrial apoptosis of human liver cells induced by arsenic through regulating Bcl-2 level.