RESUMO
The current study aimed to evaluate the potential role of dehydroepiandrosterone (DHEA) in the protection and intervention of glucocorticoid-induced secondary osteoporosis in female rats. For this purpose this study was conducted on five groups of female Sprague Dawley rats which were classified into: (1) negative control group received saline as vehicle, (2) osteoporotic group orally administered with prednisolone (5 mg/kg b.wt.) daily for six months, (3) positive control group orally administered with DHEA (250 mg/kg b.wt.) three times weekly for six months, (4) protective group orally administered with prednisolone daily with simultaneous oral administration of DHEA three times weekly for six months and (5) therapeutic group orally administered with prednisolone daily for six months then orally administered with DHEA three times weekly for other six months. The obtained data revealed that prednisolone administration resulted in significant decrease in serum osteocalcin (OC), 1,25-dihydroxyvitamin D(3) (1,25-(OH)(2) D(3)) and osteoprotegerin (OPG) levels accompanied with significant increase in serum parathyroid hormone (PTH) and receptor activator nuclear factor kappa B ligand (RANKL) levels. Histopathological investigation of left femur bone showed that prednisolone administration produced compression of the reduced articular surface and atrophy of the epiphyseal bone. On the other hand, DHEA supplementation to osteoporotic rats increased serum OC, 1,25-(OH)(2) D(3) and OPG levels while decreased serum PTH and RANKL levels. Moreover, DHEA administration resulted in restoration of intact epiphyseal bony structure and articular surface. In conclusion, DHEA via its control on glucocorticoid activity and androgenic action provided potent effect on bone.
