Lien Lillian F, Haqq Andrea M, Arlotto Michelle, Slentz Cris A, Muehlbauer Michael J, McMahon Ross L, Rochon James, Gallup Dianne, Bain James R, Ilkayeva Olga, Wenner Brett R, Stevens Robert D, Millington David S, Muoio Deborah M, Butler Mark D, Newgard Christopher B, Svetkey Laura P
Department of Medicine, Sarah W Stedman Nutrition and Metabolism Center, Duke University Medical Center, Durham, North Carolina 27710, USA.
OMICS. 2009 Feb;13(1):21-35. doi: 10.1089/omi.2008.0035.
The Study of the Effects of Diet on Metabolism and Nutrition (STEDMAN) Project uses comprehensive metabolic profiling to probe biochemical mechanisms of weight loss in humans. Measurements at baseline, 2 and 4 weeks, 6 and 12 months included diet, body composition, metabolic rate, hormones, and 80 intermediary metabolites measured by mass spectrometry. In 27 obese adults in a behavioral weight loss intervention, median weight decreased 13.9 lb over the first 6 months, then reverted towards baseline by 12 months. Insulin resistance (HOMA) was partially ameliorated in the first 6 months and showed sustained improvement at 12 months despite weight regain. Ghrelin increased with weight loss and reverted to baseline, whereas leptin and PYY fell at 6 months and remained persistently low. NPY levels did not change. Factors possibly contributing to sustained improvement in insulin sensitivity despite weight regain include adiponectin (increased by 12 months), IGF-1 (increased during weight loss and continued to increase during weight regain), and visceral fat (fell at 6 months but did not change thereafter). We observed a persistent reduction in free fatty acids, branched chain amino acids, and related metabolites that may contribute to improved insulin action. These findings provide evidence for sustained benefits of weight loss in obese humans and insights into mechanisms.
饮食对新陈代谢和营养影响的研究（STEDMAN）项目运用全面的代谢谱分析来探究人类体重减轻的生化机制。在基线、第2周和第4周、第6个月和第12个月时进行的测量包括饮食、身体成分、代谢率、激素以及通过质谱法测量的80种中间代谢物。在一项行为减肥干预中的27名肥胖成年人中，体重中位数在最初6个月下降了13.9磅，然后到12个月时又恢复至基线水平。胰岛素抵抗（HOMA）在最初6个月得到部分改善，尽管体重有所反弹，但在12个月时仍持续改善。胃饥饿素随着体重减轻而升高，之后又恢复到基线水平，而瘦素和PYY在6个月时下降，并持续保持在低水平。神经肽Y水平未发生变化。尽管体重反弹，但可能有助于胰岛素敏感性持续改善的因素包括脂联素（到12个月时升高）、胰岛素样生长因子-1（在体重减轻期间升高，在体重反弹期间持续升高）和内脏脂肪（在6个月时下降，但此后未再变化）。我们观察到游离脂肪酸、支链氨基酸及相关代谢物持续减少，这可能有助于改善胰岛素作用。这些发现为肥胖人群体重减轻的持续益处提供了证据，并深入揭示了其机制。
