Bone Abstracts

Osteoporosis, as a global public health concern, may be induced by various hazardous substances such as cadmium (Cd) and pesticide diazinon (DZN). Selenium (Se), an essential trace element, can adversely modify bone structure in higher concentrations. The current study was designed to investigate structural changes in femoral bone of adult male rats after simultaneous co-administration to Cd, DZN, and Se. A total of 20 male Wistar rats were randomly divided into two experimental groups. In the first group, young males (1-month-old) were exposed to a combination of 30 mg CdCl₂/L, 40 mg DZN/L, and 5 mg Na₂SeO₃/L in their drinking water, for 90 days. Ten 1-month-old males without toxicant application served as a control group. At the end of experiment, macroscopic and microscopic analyses of femora were performed. Our results showed no significant differences in body weight, femoral weight and femoral length between the two groups. On the other hand, cortical bone thickness was considerable decreased in rats simultaneously administered to Cd, DZN, and Se (P<0.05). Additionally, a smaller number of primary and secondary osteons was identified in these rats. Apparent symptoms of osteoporosis such as resorption lacunae and osteoporotic fractures were observed in Cd-DZN-Se-intoxicated rats. Histomorphometric evaluation revealed that area, perimeter, maximum, and minimum diameters of primary osteons’ vascular canals, Haversian canals, and secondary osteons were significantly decreased (P<0.05) in rats exposed to Cd, DZN, and Se. Our study demonstrates that subchronic co-administration to Cd, DZN, and Se harmfully affects cortical bone thickness, vascularization, and induces evident clinical manifestations of osteoporosis in male rats.