Sub-chronic lead and cadmium co-induce apoptosis protein expression in liver and kidney of rats.

The combined subchronic effects of exposure to lead acetate and cadmium chloride on apoptosis protein expression were detected in the liver and kidney of rats to investigate the hazards of environmentally relevant, low-dose exposure to these compounds. The TUNEL assay showed that there were increased numbers of apoptotic cells. Immunohistochemical tests showed increased numbers of positive cells under Bax and caspase-3 protein detection and decreased Bcl-2 protein. Furthermore, mitochondrial injury and increased numbers of apoptotic cells with condensed nuclei were observed by TEM. These results suggested that low-dose exposure to Pb and Cd can cause significant hepatic and renal apoptosis and finally impair their function. Hepatic and renal apoptosis induced by low-dose exposure is associated with mitochondrial injury and changes in levels of apoptogenic proteins, such as Bcl-2, Bax, and caspase-3.