Division of Cardiovascular Diseases, Department of Medicine, Washington University School of Medicine, St Louis, Missouri, USA.
Obesity (Silver Spring). 2012 Apr;20(4):802-10. doi: 10.1038/oby.2011.208. Epub 2011 Aug 4.
Patients with type 2 diabetes (T2DM), particularly women, are at risk for heart failure. Myocardial substrate metabolism derangements contribute to cardiac dysfunction in diabetic animal models. The purpose of this study was to determine the effects of diabetes and sex on myocardial metabolism and diastolic function in humans, separate from those of obesity. Thirty-six diabetic subjects (22 women) and 36 nondiabetic, BMI-matched subjects (21 women) underwent positron emission tomography (myocardial metabolism) and echocardiography (structure, function). Myocardial blood flow and oxygen consumption (MVO(2)) were higher in women than men (P = 0.003 and <0.0001, respectively). Plasma fatty acid (FA) levels were higher in diabetics (vs. obese, P < 0.003) and sex and diabetes status interacted in its prediction (P = 0.03). Myocardial FA utilization, oxidation, and esterification were higher and percent FA oxidation lower in diabetics (vs. obese, P = 0.0004, P = 0.007, P = 0.002, P = 0.02). FA utilization and esterification were higher and percent FA oxidation lower in women (vs. men, P = 0.03, P = 0.01, P = 0.03). Diabetes and sex did not affect myocardial glucose utilization, but myocardial glucose uptake/plasma insulin was lower in the diabetics (P = 0.04). Left ventricular relaxation was lower in diabetics (P < 0.0001) and in men (P = 0.001), and diabetes and sex interacted in its prediction (P = 0.03). Sex, T2DM, or their interaction affect myocardial blood flow, MVO(2), FA metabolism, and relaxation separate from obesity's effects. Sexually dimorphic myocardial metabolic and relaxation responses to diabetes may play a role in the known cardiovascular differences between men and women with diabetes.
患者 2 型糖尿病（T2DM），尤其是女性，存在心力衰竭风险。糖尿病动物模型中心肌底物代谢紊乱导致心脏功能障碍。本研究旨在确定糖尿病和性别对人类心肌代谢和舒张功能的影响，使其与肥胖的影响分开。36 名糖尿病患者（22 名女性）和 36 名非糖尿病、体重指数匹配的患者（21 名女性）接受正电子发射断层扫描（心肌代谢）和超声心动图（结构、功能）检查。女性的心肌血流和耗氧量（MVO2）高于男性（P = 0.003 和 <0.0001）。与肥胖者相比，糖尿病患者的血浆脂肪酸（FA）水平更高（vs. 肥胖者，P < 0.003），且性别和糖尿病状态在其预测中存在相互作用（P = 0.03）。糖尿病患者的心肌 FA 利用率、氧化和酯化较高，而 FA 氧化百分比较低（vs. 肥胖者，P = 0.0004，P = 0.007，P = 0.002，P = 0.02）。女性的 FA 利用率和酯化较高，而 FA 氧化百分比较低（vs. 男性，P = 0.03，P = 0.01，P = 0.03）。糖尿病和性别不影响心肌葡萄糖利用，但糖尿病患者的心肌葡萄糖摄取/血浆胰岛素较低（P = 0.04）。糖尿病患者的左心室舒张功能较低（P < 0.0001），男性也较低（P = 0.001），且糖尿病和性别在其预测中存在相互作用（P = 0.03）。性别、T2DM 或它们的相互作用影响心肌血流、MVO2、FA 代谢和舒张，使其与肥胖的影响分开。糖尿病对心肌代谢和舒张反应的性别差异可能在男性和女性糖尿病患者已知的心血管差异中发挥作用。
