Endocrinology and Metabolism, IRCCS Policlinico San Donato, San Donato Milanese, Italy.
Radiology Unit, IRCCS Policlinico San Donato, San Donato Milanese, Italy.
Endocrine. 2018 Feb;59(2):410-418. doi: 10.1007/s12020-017-1349-7. Epub 2017 Jun 17.
Bone marrow fat is a functionally distinct adipose tissue that may contribute to systemic metabolism. This study aimed at evaluating a possible association between bone marrow fat and insulin sensitivity indices.
Fifty obese (n = 23) and non-obese (n = 27) premenopausal women underwent proton magnetic resonance spectroscopy to measure vertebral bone marrow fat content and unsaturation index at L4 level. Abdominal visceral, subcutaneous fat, and epicardial fat were also measured using magnetic resonance imaging. Bone mineral density was measured by dual-energy X-ray absorptiometry. Body composition was assessed by bioelectrical impedance analysis. Fasting serum glucose, insulin, lipids, adiponectin were measured; the insulin resistance index HOMA (HOMA-IR) was calculated.
Bone marrow fat content and unsaturation index were similar in obese and non-obese women (38.5 ± 0.1 vs. 38.6 ± 0.1%, p = 0.994; 0.162 ± 0.065 vs. 0.175 ± 0.048, p = 0.473, respectively). Bone marrow fat content negatively correlated with insulin and HOMA-IR (r = -0.342, r = -0.352, respectively, p = 0.01) and positively with high density lipoprotein cholesterol (r = 0.270, p = 0.043). From a multivariate regression model including lnHOMA-IR as a dependent variable and visceral, subcutaneous, epicardial fat, and bone marrow fat as independent variables, lnHOMA-IR was significantly associated with bone marrow fat (β = -0.008 ± 0.004, p = 0.04) and subcutaneous fat (β = 0.003 ± 0.001, p = 0.04). Bone marrow fat, among the other adipose depots, was a significant predictor of circulating adiponectin (β = 0.147 ± 0.060, p = 0.021). Bone marrow fat unsaturation index negatively correlated with visceral fat (r = -0.316, p = 0.026).
There is a relationship between bone marrow fat content and insulin sensitivity in obese and non-obese premenopausal women, possibly mediated by adiponectin secretion. Visceral fat does not seem to regulate bone marrow fat content while it may affect bone marrow fat composition.
骨髓脂肪是一种具有不同功能的脂肪组织，可能有助于全身代谢。本研究旨在评估骨髓脂肪与胰岛素敏感指数之间的可能关联。
50 名肥胖（n=23）和非肥胖（n=27）绝经前妇女接受质子磁共振波谱检查，以测量 L4 水平的椎体骨髓脂肪含量和不饱和指数。使用磁共振成像测量腹部内脏、皮下脂肪和心外膜脂肪。通过双能 X 射线吸收法测量骨矿物质密度。通过生物电阻抗分析评估身体成分。测量空腹血糖、胰岛素、血脂、脂联素；计算胰岛素抵抗指数 HOMA（HOMA-IR）。
肥胖和非肥胖妇女的骨髓脂肪含量和不饱和指数相似（38.5±0.1% vs. 38.6±0.1%，p=0.994；0.162±0.065 vs. 0.175±0.048，p=0.473，分别）。骨髓脂肪含量与胰岛素和 HOMA-IR 呈负相关（r=-0.342，r=-0.352，p=0.01），与高密度脂蛋白胆固醇呈正相关（r=0.270，p=0.043）。从包括 lnHOMA-IR 作为因变量和内脏、皮下、心外膜脂肪和骨髓脂肪作为自变量的多元回归模型中，lnHOMA-IR 与骨髓脂肪显著相关（β=-0.008±0.004，p=0.04）和皮下脂肪（β=0.003±0.001，p=0.04）。在其他脂肪组织中，骨髓脂肪是循环脂联素的重要预测因子（β=0.147±0.060，p=0.021）。骨髓脂肪不饱和指数与内脏脂肪呈负相关（r=-0.316，p=0.026）。
在肥胖和非肥胖绝经前妇女中，骨髓脂肪含量与胰岛素敏感性之间存在关联，可能通过脂联素分泌介导。内脏脂肪似乎不会调节骨髓脂肪含量，而可能影响骨髓脂肪组成。
