RATIONALE In black women, triglycerides are paradoxically normal in the presence of insulin resistance. This relationship may be explained by race-related differences in central adiposity and SCD (stearoyl-CoA desaturase)-1 enzyme activity index. OBJECTIVE In a cross-sectional study, to compare fasting and postprandial triglyceride-rich lipoprotein particle (TRLP) concentrations and size in black compared with white pre- and postmenopausal women and determine the relationship between TRLP subfractions and whole-body insulin sensitivity, hepatic and visceral fat, and SCD-1 levels. METHODS AND RESULTS In 122 federally employed women without diabetes mellitus, 73 black (58 African American and 15 African immigrant) and 49 white; age, 44±10 (mean±SD) years; body mass index, 30.0±5.6 kg/m2, we measured lipoprotein subfractions using nuclear magnetic resonance. Hepatic fat was measured by proton magnetic resonance spectroscopy, insulin sensitivity index calculated by minimal modeling from a frequently sampled intravenous glucose test, and red blood cell fatty acid profiles were measured by gas chromatography and were used to estimate SCD-1 indices. Hepatic fat, insulin sensitivity index, and SCD-1 were similar in black women and lower than in whites, regardless of menopausal status. Fasting and postprandial large, medium, and small TRLPs, but not very small TRLPs, were lower in black women. Fasting large, medium, and very small TRLPs negatively correlated with insulin sensitivity index and positively correlated with visceral and hepatic fat and SCD-1 activity in both groups. In multivariate models, visceral fat and SCD-1 were associated with total fasting TRLP concentrations (adjR2, 0.39; P=0.001). Black women had smaller postprandial changes in large (P=0.005) and medium TRLPs (P=0.007). CONCLUSIONS Lower visceral fat and SCD-1 activity may contribute to the paradoxical association of lower fasting and postprandial TRLP subfractions despite insulin resistance in black compared with white pre- and postmenopausal women. Similar concentrations of very small TRLPs are related to insulin resistance and could be important mediators of cardiometabolic disease risk in women. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT01809288.

中文翻译：

---

甘油三酯悖论与黑人对白人妇女的脂蛋白大小，内脏脂肪和硬脂酰-CoA去饱和酶活性有关。

理由：在黑人妇女中，存在胰岛素抵抗时，甘油三酸酯反常是正常的。这种关系可以通过种族相关的中央肥胖和SCD（硬脂酰辅酶A去饱和酶）-1酶活性指数差异来解释。目的在一项横断面研究中，比较绝经前和绝经后白人与黑人相比，黑人禁食和餐后富含甘油三酸酯的脂蛋白颗粒（TRLP）的浓度和大小，并确定TRLP分级与全身胰岛素敏感性，肝脏和肝脏之间的关系。内脏脂肪和SCD-1水平。方法和结果在122名没有糖尿病的联邦雇用妇女中，有73名黑人（58名非洲裔美国人和15名非洲移民）和49名白人。年龄44±10（平均±SD）岁；体重指数，30.0±5.6 kg / m2，我们使用核磁共振测量了脂蛋白亚组分。通过质子磁共振波谱法测量肝脂肪，通过频繁采样的静脉葡萄糖试验通过最小化模型计算胰岛素敏感性指数，并通过气相色谱法测量红细胞脂肪酸谱，并用于估计SCD-1指数。黑人妇女的肝脂肪，胰岛素敏感性指数和SCD-1相似，而白人妇女则更低，而与更年期状况无关。黑人妇女的空腹和餐后大，中，小TRLP较低，但不是非常小的TRLP。两组的空腹大，中，非常小的TRLP与胰岛素敏感性指数呈负相关，与内脏，肝脂肪和SCD-1活性呈正相关。在多元模型中，内脏脂肪和SCD-1与空腹总TRLP浓度相关（adjR2，0.39； P = 0.001）。黑人妇女的大餐（P = 0.005）和中餐TRLP（P = 0.007）的餐后变化较小。结论尽管黑人与绝经前和绝经后女性相比，尽管胰岛素抵抗，但较低的内脏脂肪和SCD-1活性可能与较低的禁食和餐后TRLP分数矛盾。相似浓度的非常小的TRLP与胰岛素抵抗有关，可能是女性心脏代谢疾病风险的重要介质。临床试验注册网址：http://www.clinicaltrials.gov。唯一标识符：NCT01809288。结论尽管黑人与绝经前和绝经后女性相比，尽管胰岛素抵抗，但较低的内脏脂肪和SCD-1活性可能与较低的禁食和餐后TRLP分数矛盾。相似浓度的非常小的TRLP与胰岛素抵抗有关，可能是女性心脏代谢疾病风险的重要介质。临床试验注册网址：http://www.clinicaltrials.gov。唯一标识符：NCT01809288。结论尽管黑人与绝经前和绝经后女性相比，尽管胰岛素抵抗，但较低的内脏脂肪和SCD-1活性可能与较低的禁食和餐后TRLP分数矛盾。相似浓度的非常小的TRLP与胰岛素抵抗有关，可能是女性心脏代谢疾病风险的重要介质。临床试验注册网址：http://www.clinicaltrials.gov。唯一标识符：NCT01809288。临床试验注册网址：http://www.clinicaltrials.gov。唯一标识符：NCT01809288。临床试验注册网址：http://www.clinicaltrials.gov。唯一标识符：NCT01809288。