Protective effect of ginseng extract against apoptotic cell death induced by 2,2',5,5'-tetrachlorobiphenyl in neuronal SK-N-MC cells.

Oxidative stress plays an important role in the pathological processes of neurodegenerative diseases. Polychlorinated biphenyls (PCBs) are ubiquitous environmental contaminants, some of which may be neurotoxic. 2,2',5,5'-Tetrachlorobiphenyl (PCB 52) induces apoptotic death in human neuronal SK-N-MC cells, as demonstrated by gel electrophoresis, which demonstrates the proteolytic cleavage of beta-catenin and poly(ADP-ribose) polymerase (PARP) and the characteristic ladder patterns of DNA fragmentation. In the present study, we investigated whether Panax ginseng extract protect human neuronal SK-N-MC cells from PCB 52-induced apoptosis. The addition of 500 microg/ml of ginseng extract to a culture medium significantly protected neuronal cell from the apoptosis mediated by PCB 52 and remarkably attenuated lipid peroxidation, the generation of reactive oxygen species, and DNA fragmentation, and markedly reduced the PCB 52 induced proteolytic cleavage of beta-catenin and PARP. These results show that Panax ginseng extract protects human neuronal SK-N-MC cells from the apoptosis induced by PCB 52. We suggest that Panax ginseng extracts may protect neuronal cells from oxidative injury.