Zinc stimulates DNA synthesis during its antiapoptotic action independently with increments of an antiapoptotic protein, Bcl-2, in porcine kidney LLC-PK1 cells

Cadmium, an environmental pollutant, caused nephroptosis that was inhibitab le by zinc. The mechanism of the antiapoptotic action of zinc is poorly und erstood. In this study, we found the stimulation of DNA synthesis, as asses sed by bromodeoxyuridine incorporation, during prevention by zinc of apopto sis, suggesting that the proliferactive nature of zinc contributes to its i nhibition of apoptosis. This finding was consistent with the result that th e cells driven by dialyzed fetal bovine serum were resistant to apoptotic s timuli of cadmium. Furthermore, zinc activated the expression of endogenous Bcl-2 proteins. However, overexpression of Bcl-2 proteins by transfection did not facilitate zinc-mediated DNA synthesis. Thus, one possible role of zinc in the prevention of apoptosis is to promote DNA synthesis independent ly with activation of antiapoptotic proteins Bcl-2.