Cadmium exposure in adolescence through adulthood impairs adult hippocampal neurogenesis and cognition in mice.

Abstract

Mice were exposed to Cadmium through drinking water to examine the effects of Cd exposure in adolescent through adulthood on adult neurogenesis and cognitive function. One group of 4-week old male C57BL/6 mice (n =20) were exposed to 3 mg/L Cadmium through drinking water for 28 weeks. A serious of behavior test (Novel object location test, T-maze test, and fear conditioning test) were performed to investigate the effects of Cadmium exposure on cognition in mice. Another group of mice (n = 8) were exposed Cd for 13 weeks. BrdU labeling and immunohistochemistry were used to examine the effects of Cadmium on adult neurogenesis. In neurobehavioral group, Cadmium exposure impaired the performance of mice in the novel object location test, T-maze test and fear conditioning test, but did not affect the locomotor activity, or cause anxiety in mice. In cellular study group, the number of adult-born cell (BrdU+ ) and adult-born neurons (BrdU+ /NeuN+ ), as well as the proportion of adult-born cells that differentiated into mature neurons (BrdU+ NeuN+ cells/ total BrdU+ cells) in treated mice were significantly lower than control mice. Cadmium exposure in adolescent through adulthood can impair cognitive function through affecting adult neurogenesis.