Swanson Christine M, Shea Steven A, Kohrt Wendy M, Wright Kenneth P, Cain Sean W, Munch Mirjam, Vujović Nina, Czeisler Charles A, Orwoll Eric S, Buxton Orfeu M
Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, Colorado, US.
Oregon Institute of Occupational Health Sciences, Oregon Health & Science University, Portland, Oregon, US.
J Clin Endocrinol Metab. 2020 Jul 1;105(7):2456-63. doi: 10.1210/clinem/dgaa232.
The purpose of this work is to determine whether an uncoupling of bone turnover markers (BTMs) occurs in women exposed to the combination of sleep restriction with circadian disruption (SRCD), as previously reported in men.
Four bone biomarkers (N-terminal propeptide of type I procollagen [P1NP] and osteocalcin = bone formation; C-telopeptide [CTX] = bone resorption; sclerostin = bone formation inhibitor) were measured in bihourly samples over 24 hours at baseline and after approximately 3 weeks of sleep restriction (~5.6 hours of sleep/24 hours) with concurrent circadian disruption (SRCD, recurring 28-hour "day" in dim light). Maximum likelihood estimation in a repeated-measures model was used to assess the effects of SRCD and age on bone biomarkers.
Five women were young (22 ± 2.8 years) and four were older (58 ± 1.8 years). Baseline bone biomarker levels did not differ by age (all P ≥ .07). Bone formation markers were lower after SRCD (estimate ± SEE, ΔP1NP = -9.5 ± 2.8 μg/L, P = .01; Δosteocalcin = -2.3 ± 0.9 ng/mL, P = .04). The P1NP decline was greater in young women (ΔP1NP = -12.9 ± 3.7 μg/L, P = .01). After SRCD, CTX was significantly higher in young women (0.182 ± 0.069 ng/mL, P = .04) but did not change in older women.
These pilot data are similar to previous findings in men and suggest that SRCD negatively altered bone metabolism in women by decreasing markers of bone formation and, in young women, increasing a marker of bone resorption. If sustained, this pattern of BTM uncoupling may lead to bone loss and lower bone mineral density.
本研究旨在确定，如先前在男性中所报道的那样，睡眠限制与昼夜节律紊乱（SRCD）相结合的情况下，女性是否会出现骨转换标志物（BTM）解偶联。
在基线时以及在约3周的睡眠限制（约5.6小时睡眠/24小时）并伴有昼夜节律紊乱（SRCD，昏暗灯光下重复28小时“一天”）后，每两小时采集一次样本，检测四种骨生物标志物（I型前胶原N端前肽[P1NP]和骨钙素=骨形成；C端肽[CTX]=骨吸收；硬化蛋白=骨形成抑制剂）。使用重复测量模型中的最大似然估计来评估SRCD和年龄对骨生物标志物的影响。
5名女性较年轻（22±2.8岁），4名女性年龄较大（58±1.8岁）。基线骨生物标志物水平在年龄上无差异（所有P≥0.07）。SRCD后骨形成标志物降低（估计值±标准误，ΔP1NP=-9.5±2.8μg/L，P=0.01；Δ骨钙素=-2.3±0.9ng/mL，P=0.04）。年轻女性中P1NP的下降幅度更大（ΔP1NP=-12.9±3.7μg/L，P=0.01）。SRCD后，年轻女性的CTX显著升高（0.182±0.069ng/mL，P=0.04），而老年女性则无变化。
这些初步数据与先前在男性中的研究结果相似，表明SRCD通过降低骨形成标志物并在年轻女性中增加骨吸收标志物，对女性的骨代谢产生了负面影响。如果这种情况持续下去，这种BTM解偶联模式可能会导致骨质流失和骨矿物质密度降低。
