Department of Medicine, University of Helsinki, Helsinki, Finland.
Arterioscler Thromb Vasc Biol. 2011 Sep;31(9):2144-50. doi: 10.1161/ATVBAHA.111.224808. Epub 2011 Jul 21.
Obesity increases the risk of cardiovascular disease and premature death. However, not all obese subjects develop the metabolic abnormalities associated with obesity. The aim of this study was to clarify the mechanisms that induce dyslipidemia in obese subjects.
Stable isotope tracers were used to elucidate the pathophysiology of the dyslipidemia in hypertriglyceridemic (n=14) and normotriglyceridemic (n=14) obese men (with comparable body mass index and visceral fat volume) and in normotriglyceridemic nonobese men (n=10). Liver fat was determined using proton magnetic resonance spectroscopy, and subcutaneous abdominal and visceral fat were measured by magnetic resonance imaging. Serum triglycerides in obese subjects were increased by the combination of increased secretion and severely impaired clearance of triglyceride-rich very-low-density lipoprotein(1) particles. Furthermore, increased liver and subcutaneous abdominal fat were linked to increased secretion of very-low-density lipoprotein 1 particles, whereas increased plasma levels of apolipoprotein C-III were associated with impaired clearance in obese hypertriglyceridemic subjects.
Dual metabolic defects are required to produce hypertriglyceridemia in obese subjects with similar levels of visceral adiposity. The results emphasize the clinical importance of assessing hypertriglyceridemic waist in obese subjects to identify subjects at high cardiometabolic risk.
肥胖会增加心血管疾病和过早死亡的风险。然而，并非所有肥胖者都会出现与肥胖相关的代谢异常。本研究旨在阐明导致肥胖者血脂异常的机制。
使用稳定同位素示踪剂来阐明高甘油三酯血症（n=14）和正常甘油三酯血症（n=14）肥胖男性（具有可比的体重指数和内脏脂肪量）以及正常甘油三酯血症非肥胖男性（n=10）的血脂异常的病理生理学。使用质子磁共振波谱法测定肝脂肪，通过磁共振成像测量皮下腹部和内脏脂肪。肥胖者的血清甘油三酯水平升高是由于甘油三酯丰富的极低密度脂蛋白（1）颗粒的分泌增加和清除严重受损所致。此外，肝和皮下腹部脂肪增加与极低密度脂蛋白 1 颗粒的分泌增加有关，而载脂蛋白 C-III 的血浆水平增加与肥胖高甘油三酯血症患者的清除受损有关。
在具有相似内脏脂肪量的肥胖者中，产生高甘油三酯血症需要双重代谢缺陷。这些结果强调了评估肥胖者高甘油三酯血症腰围以识别心血管代谢风险高的患者的临床重要性。
