caa a22 4500 378898086 CHVBK 20180305123511.0 cr unu---uuuuu 161128e20041201xx s 000 0 eng 10.1515/CCLM.2004.258 doi (NATIONALLICENCE)gruyter-10.1515/CCLM.2004.258 The assessment of bone metabolism in female elite endurance athletes by biochemical bone markers [Elektronische Daten] [Markus Herrmann, Wolfgang Herrmann] Purpose: Premature osteoporosis is a frequent problem in female athletes. Current concepts suggest that a disruption of the hypothalamic-pituitary axis leads to hypoestrogenism, which then causes amenorrhea and osteoporosis. However, the underlying mechanisms have been insufficiently investigated. Osteoprotegerin (OPG) and soluble TNF-α receptor antagonist ligand (sRANKL) regulate the balance of osteoblasts and osteoclasts. Their role in the pathogenesis of osteoporosis in female athletes has not been studied yet. Methods: We measured OPG and sRANKL in relation to biochemical bone markers [osteocalcin (OC), bone alkaline phosphatase (BAP), serum β-crosslaps (CTx)] and female sex hormones [estradiol (E2) and luteinizing hormone (LH)] in fastening blood samples from 25 female elite endurance athletes and 25 matched controls. Results: Athletes exhibited significantly higher levels of the bone resorption marker CTx than controls (0.61±0.26 vs. 0.44±0.15ng/ml). OPG and sRANKL were not changed. Subgroup analysis revealed that athletes using oral contraceptives [A-OCC(−)] had significantly higher levels of CTx (0.82±0.20 vs. 0.50±0.14ng/ml), BAP [37.3 (23.2-54.4) U/l vs. 25.2 (20.3-35.6) U/l] and OPG (3.4±0.8 vs. 2.7±0.8ng/ml) than controls who did not use oral contraceptives [C-OCC(−)]. While the difference for CTx exceeded the least significant change in this marker by approximately 30%, the differences for the bone formation markers OC and BAP were close to the least significant change. In athletes using oral contraceptives [A-OCC(+)] we found no differences compared to controls. Conclusions: A-OCC(−) athletes have increased bone turnover with a particular stimulation of bone resorption. The increased bone resorption is not accompanied by a shift of the OPG/sRANKL relationship towards an osteoclastogenic constellation. Since increased bone resorption was not detectable in A-OCC(+) athletes, it can be suggested that OCC use might protect bone health in female athletes. ©2004 by Walter de Gruyter Berlin New York Medical equipment & techniques nationallicence Medical diagnosis nationallicence Diseases & disorders nationallicence bone alkaline phosphatase (BAP) nationallicence exercise nationallicence osteocalcin (OC) nationallicence osteoprotegerin (OPG) nationallicence serum β-crosslaps (CTx) nationallicence soluble TNF-α-receptor antagonist ligand (sRANKL) nationallicence Herrmann Markus Department of Clinical Chemistry and Laboratory Medicine, University Hospital of Saarland, Homburg/Saar, Germany aut Herrmann Wolfgang Department of Clinical Chemistry and Laboratory Medicine, University Hospital of Saarland, Homburg/Saar, Germany aut Clinical Chemical Laboratory Medicine Walter de Gruyter 42/12(2004-12-01), 1384-1389 1434-6621 42:12<1384 2004 42 cclm https://doi.org/10.1515/CCLM.2004.258 text/html Onlinezugriff via DOI 1 research article jats NATIONALLICENCE 856 40 https://doi.org/10.1515/CCLM.2004.258 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Herrmann Markus Department of Clinical Chemistry and Laboratory Medicine, University Hospital of Saarland, Homburg/Saar, Germany aut NATIONALLICENCE 700 1- Herrmann Wolfgang Department of Clinical Chemistry and Laboratory Medicine, University Hospital of Saarland, Homburg/Saar, Germany aut NATIONALLICENCE 773 0- Clinical Chemical Laboratory Medicine Walter de Gruyter 42/12(2004-12-01), 1384-1389 1434-6621 42:12<1384 2004 42 cclm CC0 http://creativecommons.org/publicdomain/zero/1.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-gruyter