Abstract: Cadmium is a common environmental pollutant, which causes cell apoptosis. Recently, some researches have shown low levels of cadmium exposure could cause cell autophagy. Autophagy, an evolutionarily conserved mechanism for sequestering and degrading long-lived cellular proteins and damaged organelles, is important in normal development and serve as a response to changing environmental stimuli. Its alteration is associated with many physiological and pathological process of the body, such as neurodegenerative diseases, cancer, pathogenic microorganism infection. The molecular mechanism of autophagy induced by cadmium is involved in many signal pathways, which can be induced by the generation of reactive oxygen species(ROS) and to activate liver kinase B1-AMP-activated protein kinase (LKB1-AMPK) signaling pathway, or a rapid elevation in cytosolic calcium to activate calmodulin-dependent protein kinase. Autophagy can also be induced by ER stress. Numerous studies show that autophagy induced by cadmium plays an important role in cell death, while other studies indicate that autophagy can serve as a protective mechanism against cadmium caused cell death. Although the cadmium induced autophagy has been investigated intensively, the underlying mechanisms are not yet completely understood. The purpose of this review was to elaborate the molecular mechanism of autophagy induced by cadmium.

Key words: cadmium, autophagy, ROS, calcium signal pathway