ROLE OF CARNOSINE IN PREVENTION AND TREATMENT OF OSTEOPOROTIC LUMBAR VERTEBRAE OF OVARIECTOMIZED HAMSTERS

Document Type : Original Article

Authors

1 Departments of Biochemistry, Anatomy Faculty of Medicine, Cairo University

2 Departments of Histology, Faculty of Medicine, Cairo University

Abstract

Estrogen plays an important role in the growth and maturation of bone as well as in the regulation of its turnover to maintain bone balance in adults. During bone growth. estrogen is needed for proper closure of epiphyseal plates both in females and males (Vaananen and Harkonen, 1996). In the adult. both bone formation and resorption occur side by side in a process called remodeling where bone formation equals the amount of that lost during resorption. With aging, resorption becomes more active than formation with a net loss of bone mass (Lindsay et al., 1980). Estrogen withdrawal as a result of menopause or induced by ovariectomy leads to osteoporosis as a result of a decrease in bone formation and an increase in bone resorption (Sun et al., 1997; Chen et aI., 2000), however, the decrease in bone formation may precede the increase in bone resorption (SeifertKlauss et al., 2002). The mechanisms which have been suggested for the development of osteoporosis following estrogen withdrawal include stimulation of theproduction of bone resorbing cytokines which stimulates osteoclast formation in bone marrow (Vaananen and Harkonen, 1996), reduction of osteoprotegerin in the osteoblasts resulting in stimulation of bone resorption (Liao et at, 2002) and reduction
of the life-span of osteohlasts and increase of the life-span of osteoclasts (Chen et aI., 2000).

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