Regulation of Cell Fate by Cadmium and Zinc

Abstract

Effects of the heavy metals cadmium and zinc on the regulation of cell destiny are reviewed in light of an apoptogenic metal of cadmium and the antiapoptotic nature of zinc. Exposure of renal cells to cadmium causes apoptotic features, DNA fragmentation and chromatin condensation in earlier stages of cadmium cytotoxicity than the cadmium-induced necrotic phase. The molecular mechanism of cadmium-induced apoptosis is poorly understood. Neither cadmium-metallothionein nor an immediate early gene such as c-myc is involved in the apoptotic pathway. In contrast, zinc can abolish cadmium-induced apoptosis. Although the mechanism underlying zinc inhibition of apoptosis remains uncertain, one possibility is that the ability of zinc to facilitate DNA synthesis might contribute to its protective effect on apoptosis.