Bone Developmental Toxicology Studies of Cadmium Chloride in Juvenile Sprague Dawley Rats

Author(s): Shuyan Wang, Haimei Zhu, Qi Zhao, Shenning Li, Caiyun Li, Yunliang Qiu, Yan Chang.

Cadmium (Cd) exposure is able to reduce the accumulation of bone mass and exert influence on bone maturity and differentiation. Children are in a critical period of bone maturity and differentiation. This study used juvenile rats to assess Cd effects on bone development. Four groups of 8 male and 8 female juvenile Sprague Dawley (SD) rats were treated with 0 (vehicle, deionized water), 0.5, 1.5, or 5.0 mg/kg/day cadmium chloride orally once daily for 9 weeks, on Postnatal Days (PND) 8 to 70. Bone development parameters, bone metabolism parameters, bone mineral density (BMD), and bone histomorphology were measured. The results showed that Cd accumulation in bone and blood caused severe damage to bone. Body weights, crown-rump lengths, bone lengths and weight gains in the 5.0 mg/kg/day group were statistically lower than those in the vehicle control group. The results of micro computed tomography (Micro-CT) and histological analysis revealed that the bone microstructure of the 5.0 mg/kg/day group has been significantly disrupted, especially trabecular, and the BMD of femur and tibia were reduced. Thus, cadmium chloride impaired bone development in juvenile rats, which may provide references for the toxicity of cadmium chloride and therapeutic target for Cd-associated bone damage in children.