Department of Surgery, University of Alabama at Birmingham and the Birmingham VA Medical Center, KB401, 1720 2nd Ave S, Birmingham, AL, 35294-0016, USA.
Department of Nutrition Sciences, University of Alabama at Birmingham and the Birmingham VA Medical Center, 1675 University Boulevard, Birmingham, AL, 35294-3360, USA.
Curr Obes Rep. 2015 Jun;4(2):287-302. doi: 10.1007/s13679-015-0155-x.
Weight loss, whether achieved by lifestyle intervention, pharmacotherapy, or bariatric surgery, is highly effective as a primary interventional strategy in both the prevention and treatment of type 2 diabetes. In high-risk patients with prediabetes and/or metabolic syndrome, weight loss effectively prevents progression to type 2 diabetes mellitus (T2DM) and improves cardiovascular risk factors. These benefits are the result of improvements in insulin resistance, which is central to the pathophysiology of cardiometabolic disease. In patients with T2DM, weight loss improves glycemia, while reducing the need for conventional glucose-lowering medicines, by affecting all three processes that produce and sustain the hyperglycemic state, namely via increments in peripheral insulin sensitivity with improvements in insulin signal transduction at the cellular level, more robust insulin secretory responses, and reduced rates of hepatic glucose production. In both nondiabetic and diabetic subjects, hypocaloric feeding (e.g., treatment with very low-calorie diet or bariatric surgery) produces a rapid improvement in insulin sensitivity due to mobilization of fat from the intramyocellular, intrahepatocellular, and intra-abdominal compartments, and via a more long-term mechanism that correlates with the loss of total body fat. In diabetes, by improving glycemia, weight loss also enhances glucose homeostasis by reversing the defects in insulin action and secretion attributable to glucose toxicity. Regardless of the therapeutic approach, weight loss of ∼ 10 % maximally prevents future diabetes in patients with prediabetes or metabolic syndrome. In T2DM, greater degrees of weight loss lead to progressive improvements in glucose homeostasis. Therefore, when accompanied by greater weight loss, the metabolic benefits following bariatric surgery are generally more pronounced than those achieved following lifestyle and medical treatment. In addition, the mechanisms by which bariatric operations improve diabetes may include both weight-dependent and weight-independent mechanisms, and the latter may involve changes in gut hormones, bile acids, or gut microflora.
无论通过生活方式干预、药物治疗还是减重手术实现，体重减轻作为 2 型糖尿病（T2DM）预防和治疗的主要干预策略，效果显著。在存在糖尿病前期和/或代谢综合征高危风险的患者中，体重减轻可有效预防 T2DM 的进展，并改善心血管危险因素。这些益处是由于胰岛素抵抗得到改善，而胰岛素抵抗是心脏代谢疾病病理生理学的核心。在 T2DM 患者中，体重减轻可通过影响产生和维持高血糖状态的三个过程来改善血糖，同时减少对传统降血糖药物的需求，这三个过程分别是外周胰岛素敏感性增加、细胞水平胰岛素信号转导改善、胰岛素分泌反应更有力，以及肝葡萄糖产生率降低。在非糖尿病和糖尿病患者中，低热量饮食（例如，极低热量饮食或减重手术治疗）通过动员肌内、肝内和腹内脂肪库中的脂肪，以及通过与全身脂肪丢失相关的更长期机制，可迅速改善胰岛素敏感性。在糖尿病中，体重减轻通过改善血糖，也可通过逆转葡萄糖毒性导致的胰岛素作用和分泌缺陷，来增强葡萄糖稳态。无论采用何种治疗方法，体重减轻约 10%可最大限度地预防糖尿病前期或代谢综合征患者的未来糖尿病。在 T2DM 中，体重减轻程度越大，葡萄糖稳态的改善越显著。因此，当与更大程度的体重减轻相关时，减重手术后的代谢益处通常比生活方式和药物治疗更为明显。此外，减重手术改善糖尿病的机制可能包括体重依赖性和非体重依赖性机制，后者可能涉及肠道激素、胆汁酸或肠道微生物群的变化。
