Effect of zinc supplementation on calcium homeostasis and bone metabolism in glucocorticoid treated rats

الملخص EN

Glucocorticoids are essential for life and have broad therapeutic uses.

However, they may alter calcium homeostasis as well as bone metabolism and growth.

The present work designed to demonstrate the effects of glucocorticoids on calcium homeostasis and bone metabolism .

The study also demonstrates the protective role of nutritional zinc supplementation on glucocorticoids effects.

Forty eight male albino rats were used for the experiment, divided equally into 4 groups: a control group , a group receiving glucocorticoid (Glue.), a group receiving both glucocorticoid and zinc(Gluc + Zn) and a group receiving zinc (Zn).

The duration of the experiment was 30 days.

The study revealed, occurrence of significant hypocalcemia and marked reduction of plasma bone formation markers level(alkaline phosphatase and osteocalcin) associated with hyperparathyroidism in glucocorticoid treated rats compared to their controls.Also,the histological results revealed significant reduction of bone formation and growth as manifested by decrease trabecular bone mass of cancellous bone which appeared basophilic and highly erroded with frequently seen osteoclasts.Numerous cavities were detected in thinned out compact bone.

Zones of growing cartilage appeared distorted and thinned out.

Concomitant administration of zinc with glucocorticoid showed marked limitation in the adverse effects of glucocorticoids on calcium homeostasis and bone metabolism as evident by insignificant differences in plasma calcium.