title: Changes in bone resorption during the menstrual cycle.
abstract: To determine if the cyclic changes of female sex hormones during the menstrual cycle are related to changes in bone formation and resorption, we measured serum bone-specific alkaline phosphatase (BAP) and osteocalcin (OC) and bone resorption markers, serum and urine deoxypyridinoline (Dpyr), three times per week during one menstrual cycle in 20 healthy premenopausal women. Serum estradiol (E2) and progesterone (P) showed characteristic cyclic fluctuations. Serum Dpyr was higher during the follicular phase (FP) than in the luteal phase (p = 0.027). Serum BAP, OC, and urine Dpyr levels did not change substantially across the cycle. Serum Dpyr correlated negatively with serum E2 values measured 6 (p = 0.011) and 8 (p = 0.001) days earlier and with P measured concurrently (p = 0.033) 2 (p = 0.002), 4 (p = 0.003), and 6 (p = 0.014) days earlier. BAP correlated negatively with E2 measured 6 days earlier (p = 0.006). We found no statistically significant correlations of E2 or P with OC or urine Dpyr within women over their cycles. BAP was positively correlated with concurrent serum Dpyr (p = 0.015) during the menstrual cycle. Serum OC levels correlated inversely with age (rs = -0.48, p = 0.036). Women with higher mean urine Dpyr levels had higher mean serum OC levels (rs = 0.49, p = 0.033) and showed a trend toward lower hip bone mineral density (rs = -0.40, p = 0.078). We conclude that the low level of E2 and/or P observed during the FP of the normal menstrual cycle is associated with increased bone resorption. These relationships suggest that normal women experience monthly episodes of increased bone resorption from menarche to menopause.
authors.affiliation: Program in Osteoporosis and Bone Biology, University of California, San Francisco, USA.
authors.forename: K M
authors.initials: KM
authors.lastname: Chiu
authors.forename: J
authors.initials: J
authors.lastname: Ju
authors.forename: D
authors.initials: D
authors.lastname: Mayes
authors.forename: P
authors.initials: P
authors.lastname: Bacchetti
authors.forename: S
authors.initials: S
authors.lastname: Weitz
authors.forename: C D
authors.initials: CD
authors.lastname: Arnaud
mesh_terms: D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood; D000596:Amino Acids / Q000097:blood / Q000652:urine; D015415:Biomarkers; D015519:Bone Density; D001862:Bone Resorption / Q000503:physiopathology*; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood; D008597:Menstrual Cycle / Q000502:physiology*; D015675:Osteocalcin / Q000097:blood; D011374:Progesterone / Q000097:blood
chemical_list: D000596:Amino Acids; D015415:Biomarkers; D015675:Osteocalcin; D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; C036020:deoxypyridinoline; D000469:Alkaline Phosphatase