Down Regulation of Osteocalcin Gene in Chickens Treated with Cadmium

Cadmium is one of the heavy metals with harmful effects on different body organs and systems. The aim of this study was to investigate the harmful effects of cadmium, as a heavy metal, on the histological structure of bone and the expression of osteocalcin gene. Forty chickens were obtained, anesthetized and their femurs were surgically removed. The real time polymerase chain reaction (PCR) was used to study the osteocalcin gene expression. The osteocalcin gene expression rate were: 1.000± 0.1; 0.86± 0.01; 0.63± 0.09, and 0.41± 0.06 in the controls, experiment I, experiment II and experiment III groups, respectively (P < 0.05). Also, the nuclear pyknosis in osteocytes and decreased bone formation were observed in the histology slides of the chicken bones. We conclude that cadmium adversely affected the chicken bones as evident by the decreased osteocalcin gene expression and the adverse effects on the bone histology. We recommend that plans be developed to prevent the outbreak of cadmium and other heavy metals in animal and human environment.