Aluminum Toxicity as aRisk Factor to Osteoporosis in Aging Rats

Background: Aluminum has the potential to be cytotoxic for humans and animals. Al absorption is increased with age and bone is considered as its main storage site. Aim of the Work: This study was carried out to investigate the pathological changes in bone of aging rats, treated with aluminum chloride. Material and Methods: Twenty male albino rats (2-years age at the beginning of the experiment) were divided into a control group and an experimental group. The latter subjected to aluminum chloride ingestion for 8 weeks. Plain X-rays as well H&E stain were used to investigate the pathological changes of the femur of the experimental group. Results: In the experimental group, plain x-ray of femurs revealed destruction of medullary bone trabeculae, cortical bone resorption and sclerosis. H&E sections at the proximal end of the shaft of the femur confirmed the gross picture of x-ray and the cortex of the bone appeared thin with erosion cavities leading to fracture in some specimens. The bone cells appeared few or degenerated and the periosteum appeared thin and separated. The inner cancellous bone trabeculae was destroyed and separated by widened bone marrow that may be replaced by fat cells. Ultrastructurally, both osteoblasts and osteocytes showed marked degenerative changes and were surrounded by few irregular collagenous matrix. The degenerative bone changes observed in this study may, in part, be interpreted as a consequence of aluminum administration.