Urinary Glycosaminoglycan Concentrations in Postmenopausal Osteoporosis

Authors: Bilgin ÖZMEN, Dilek ÖZMEN, Işıl MUTAF, Nevbahar TURGAN, İnci GÜNER, Oya BAYINDIR

Abstract: The organic bone matrix contains glycosaminoglycans (GAGs). Structural changes in bones with inflammatory and degenerative processes generally lead to the break-down of macromolecules from connective tissue and increase their urinary excretion. In the present study, the levels of urinary GAGs were investigated in 28 healthy controls consisting of 18 premenopausal and 10 postmenopausal women and 25 patients with postmenopausal and 10 postmenopausal women and in 25 patients with postmenopausal osteoporosis. Urinary GAGs were measured in 24 hour collected urine samples by the carbazole method and corrected for the excretion level of creatinine. There was a significant increase in GAGs excretion in patients with postmenopausal osteoporosis compared with healthy premenopausal (p<0.01) and healty postmenopausal subjects (p<0.01). (4.57+-0.69 in healty premenopausal and 5.34+-1.64 mm/mol creatinine in healty postmenopausal vs 12.31+-1.01 mmol/mol creatinine in postmnopausal osteoporotic women). Bone mineral density was measured by dual photon absortiometer. Bone mineral density was determined to be significantly lower in postmenopausal women with osteoporosis in comparison to the control group (p<0.05). In urine samples collected in the 4. week of salmon calcitonin (SCT) treatment (100 IU/d Miacalsic), GAG excretion decreased significantly in the osteoporotic women, suggesting that this urinary parameter might be useful in monitoring alterations in bone metabolism.

Keywords: Postmepoausal osteoporosis, Glycosaminoglycans, Menopause, Calcitonin.