Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA.
Obesity (Silver Spring). 2013 Dec;21(12):E527-32. doi: 10.1002/oby.20453. Epub 2013 Jun 13.
Undercarboxylated osteocalcin (ucOC) is a bone marker with potent metabolic effects. Leptin regulates Esp gene expression and osteocalcin carboxylation in animal models. We aim to elucidate day/night patterns of ucOC levels, whether short-term and/or chronic energy deprivation alters ucOC levels, and whether leptin may mediate these changes in humans.
Twelve healthy males and females were studied for 72 h in the fed state to study day/night pattern of ucOC. The six female subjects were also studied in a crossover interventional study in the fasting state for 72 h with administration of either placebo or metreleptin in physiological doses. Blood samples were obtained hourly from 0800 a.m. on day 3 until 0800 a.m. on day 4. In a separate study, eleven obese subjects who underwent bariatric surgery were followed for 24 weeks to examine the effects of postsurgery weight loss on ucOC levels.
Males have higher ucOC levels compared to females. There is no day/night variation pattern of circulating ucOC in humans. Short-term and chronic energy deprivation or leptin administrations do not alter ucOC levels.
The hypothesis that ucOC plays a role in energy homeostasis or of leptin in regulating ucOC in humans is not supported.
非羧化骨钙素（ucOC）是一种具有强大代谢作用的骨标志物。瘦素调节动物模型中 Esp 基因表达和骨钙素羧化。我们旨在阐明 ucOC 水平的昼夜模式，短期和/或慢性能量剥夺是否改变 ucOC 水平，以及瘦素是否可以介导人类的这些变化。
12 名健康男性和女性在进食状态下进行了 72 小时研究，以研究 ucOC 的昼夜模式。六名女性受试者还在禁食状态下进行了交叉干预研究，在禁食状态下进行了 72 小时，并以生理剂量给予安慰剂或 metreleptin。从第 3 天上午 8 点开始，每小时采集一次血样，直到第 4 天上午 8 点。在另一项研究中，对 11 名接受减肥手术的肥胖患者进行了 24 周的随访，以检查手术后体重减轻对 ucOC 水平的影响。
男性的 ucOC 水平高于女性。人类循环 ucOC 没有昼夜变化模式。短期和慢性能量剥夺或瘦素给药不会改变 ucOC 水平。
ucOC 在能量平衡中发挥作用或瘦素调节人类 ucOC 的假设未得到支持。
