National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), NIH, Bethesda, Maryland, USA.
NIH Clinical Center (CC), Bethesda, Maryland, USA.
JCI Insight. 2018 Sep 20;3(18). doi: 10.1172/jci.insight.121495.
Black women, compared with White women, have high rates of whole-body insulin resistance but a lower prevalence of fasting hyperglycemia and hepatic steatosis. This dissociation of whole-body insulin resistance from fasting hyperglycemia may be explained by racial differences in gluconeogenesis, hepatic fat, or tissue-specific insulin sensitivity. Two groups of premenopausal federally employed women, without diabetes were studied. Using stable isotope tracers, [2H2O] and [6,62-H2]glucose, basal glucose production was partitioned into its components (gluconeogenesis and glycogenolysis) and basal whole-body lipolysis ([2H5]glycerol) was measured. Indices of insulin sensitivity, whole-body (SI), hepatic (HISIGPR), and adipose tissue, were calculated. Hepatic fat was measured by proton magnetic resonance spectroscopy. Black women had less hepatic fat and lower fractional and absolute gluconeogenesis. Whole-body SI, HISIGPR, and adipose tissue sensitivity were similar by race, but at any given level of whole-body SI, Black women had higher HISIGPR. Therefore, fasting hyperglycemia may be a less common early pathological feature of prediabetes in Black women compared with White women, because gluconeogenesis remains lower despite similar whole-body SI.
黑人女性与白人女性相比，全身胰岛素抵抗的发生率较高，但空腹高血糖和肝脂肪变性的患病率较低。全身胰岛素抵抗与空腹高血糖的这种分离可能与肝内葡萄糖生成、肝内脂肪或组织特异性胰岛素敏感性的种族差异有关。研究了两组没有糖尿病的联邦在职的绝经前女性。使用稳定同位素示踪剂[2H2O]和[6,62-H2]葡萄糖，将基础葡萄糖生成分为其组成部分（糖异生和糖原分解），并测量基础全身脂肪分解（[2H5]甘油）。计算了胰岛素敏感性指数，全身（SI）、肝（HISIGPR）和脂肪组织。通过质子磁共振波谱测量肝内脂肪。黑人女性的肝内脂肪较少，糖异生的分数和绝对值较低。尽管种族间全身 SI 相似，但全身 SI 相同的情况下，黑人女性的 HISIGPR 更高。因此，与白人女性相比，空腹高血糖可能是黑人女性糖尿病前期的一种不太常见的早期病理特征，因为尽管全身 SI 相似，但糖异生仍然较低。
