Cadmium Inducing Damage Of Isolated Mitochondrial In HEK 293 Cells

Cadmium can induce apoptosis in many kinds of cells. Studying the damage of isolated mitochondria induced by cadmium is necessary for us to cure lots of diseases caused by cadmium. And it is also very important for the molecular toxicological study of cadmium. This paper studied some aspects of cadmium-induced damage of isolated mitochondria from HEK293 cells:1 The damage of mitochondria membrane induced by cadmiumThe opening of the mitochondrial permeability transition pore (MPTP) was tested by spectrophotometer. Morphological changes of mitochondria were observed under transmission electron microscope and mitochondrial membrane potential (MMP) was monitored by spectrofluorimeter with fluorescence dye Rh-123. The results showed that MPTP of exposed groups decreased compared with that of the control group, and it can be inhibited by Cs A. Mitochondria incubated by CdCl₂ were found swell under transmission electron microscope.2 The change of ROS and antioxidases induced by cadmiumThe contents of ROS were detected with DCFH-DA. Superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the contents of malondialdehyde (MDA) which related with oxidative stress were also monitored. Taken together, our results showed that the damage of mitochondria induced by CdCl₂ may involve mitochondrial disruption including both the increasing of the ROS contents and the decrease of activities of antioxidases. and the contents of MDA of exposed groups increased significantly compared with that of control group.3 The impact of cadmium on some enzymes in isolated mitochondriaThe activities of ATPase and lactate dehydrogenase (LDH) were measured by spectrophotometer. We found that activities of Na⁺-K⁺-ATPase, Ca²⁺-Mg²⁺-ATPase and LDH were decreased with the increased concentration of CdCl₂ ; It suggests that CdCl₂ may lead to energy metabolism obstacles in HEK293 cells damage.