Department of Endocrinology and Metabolism, Shanghai Jiao Tong University Affiliated Sixth People's Hospital; Shanghai Clinical Center for Diabetes; Shanghai Key Clinical Center for Metabolic Disease; Shanghai Diabetes Institute, Shanghai Key Laboratory of Diabetes Mellitus, 600 Yishan Road, Shanghai, 200233, China.
Department of Radiology, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, 200233, China.
Cardiovasc Diabetol. 2018 Nov 13;17(1):143. doi: 10.1186/s12933-018-0786-9.
The aim of this study was to investigate the interrelationships between three bone-derived factors [serum osteocalcin (OCN), fibroblast growth factor (FGF) 23, and neutrophil gelatinase-associated lipocalin (NGAL) levels] and body fat content and distribution, in order to reveal the potential endocrine function of bone in the development of obesity.
We recruited 1179 people (aged 59.5 ± 6.2 years) from communities in Shanghai. Serum OCN levels were determined using an electrochemiluminescence immunoassay. Serum FGF23 and NGAL levels were determined using a sandwich enzyme-linked immunosorbent assay. The abdominal fat distribution, including visceral fat area (VFA), was assessed by magnetic resonance imaging. Visceral obesity was defined as a VFA ≥ 80 cm.
Serum OCN levels were inversely correlated with body fat parameters, while FGF23 and NGAL were positively correlated (P < 0.05). After adjusting for confounders, waist circumference (W) and VFA had a closer relationship with serum OCN, FGF23, and NGAL levels than body mass index (BMI) and body fat percentage (fat%, all P < 0.05). The risk of visceral obesity significantly increased with higher FGF23 and/or NGAL levels, as well as with reduced OCN levels (all P < 0.05). In addition, serum OCN, FGF23, and NGAL levels were independently associated with visceral obesity (all P < 0.01). The relationships persisted among subjects with normal glucose tolerance or subjects with hyperglycaemia (both P < 0.05).
Compared to the indicators of overall adiposity such as BMI or fat%, visceral adiposity indicators (W or VFA) were more closely related to serum OCN, FGF23 and NGAL levels. There was no interaction among the relationship of three bone-derived factors with visceral obesity, which revealed the independent relationship of endocrine function of skeleton with body fat.
本研究旨在探讨三种骨源性因子（血清骨钙素[OCN]、成纤维细胞生长因子 23[FGF23]和中性粒细胞明胶酶相关脂质运载蛋白[NGAL]水平）与体脂含量和分布的相互关系，以揭示骨骼在肥胖发生过程中的潜在内分泌功能。
我们从上海社区招募了 1179 人（年龄 59.5±6.2 岁）。采用电化学发光免疫分析法测定血清 OCN 水平。采用夹心酶联免疫吸附试验测定血清 FGF23 和 NGAL 水平。采用磁共振成像评估腹部脂肪分布，包括内脏脂肪面积（VFA）。内脏肥胖定义为 VFA≥80cm。
血清 OCN 水平与体脂参数呈负相关，而 FGF23 和 NGAL 则呈正相关（P<0.05）。校正混杂因素后，腰围（W）和 VFA 与血清 OCN、FGF23 和 NGAL 水平的相关性较 BMI 和体脂百分比（fat%）更为密切（均 P<0.05）。随着 FGF23 和/或 NGAL 水平升高及 OCN 水平降低，内脏肥胖的风险显著增加（均 P<0.05）。此外，血清 OCN、FGF23 和 NGAL 水平与内脏肥胖独立相关（均 P<0.01）。在糖耐量正常或高血糖的受试者中，上述关系仍然存在（均 P<0.05）。
与 BMI 或 fat%等总体肥胖指标相比，内脏肥胖指标（W 或 VFA）与血清 OCN、FGF23 和 NGAL 水平更为密切相关。三种骨源性因子与内脏肥胖的关系之间没有相互作用，这揭示了骨骼内分泌功能与体脂之间的独立关系。
