Chen Kai, Xiao Boen, Zhou Zhe, Peng Weihui, Liu Wei
Department of Biliopancreatic Surgery and Metabolic Surgery, Second Xiangya Hospital, Central South University, Changsha, People's Republic of China.
Diabetes Metab Syndr Obes. 2020 May 6;13:1545-1553. doi: 10.2147/DMSO.S252971. eCollection 2020.
Roux-en-Y gastric bypass (RYGB) has been proved to be more effective than other bariatric procedures in the long term on body-weight loss and remission of diabetes. However, the mechanism remains poorly understood. Long-term changes in energy metabolism after RYGB have rarely been reported.
To investigate the long-term effects of RYGB on energy metabolism on a diet-induced obesity (DIO) mouse model.
DIO mice fed a high-fat diet were assigned to two groups: RYGB (n=8) and sham (n=7), followed by high-fat diet feeding until 12 weeks after surgery. Body weight and food intake were recorded weekly. Measurement of body composition and energy metabolism by metabolic chamber were conducted at weeks 4, 8, and 12 after surgery. Fecal energy measurement, intraperitoneal glucose-tolerance tests, and insulin-tolerance tests were conducted at postoperative week 12.
Food intake was reduced in the RYGB group within the first 3 weeks after surgery and increased to the same as the sham group from postoperative week 4. At 12 weeks after surgery, body weight had reduced by 36%±3.2% in the RYGB group compared to a 16%±2% body-weight gain in the sham group, while fat mass had reduced significantly in the RYGB group compared to the sham group (9.2%±1.5% versus 30.1%±0.7%). Energy expenditure was significantly higher at postoperative week 8 in the RYGB group than the sham group. In comparison with the sham group, the respiratory exchange ratio was unchanged, decreased, and increased in the RYGB group at postoperative weeks 4, 8, and 12, respectively. Fecal energy measurement showed that feces from mice in the RYGB group contained higher energy levels than the sham group. Glucose metabolism had significantly improved in the RYGB group, in contrast to the sham group, demonstrated by intraperitoneal glucose tolerance tests (AUC 1,502±104 versus 2,277±198, respectively) and insulin tolerance tests (AUC 524±50 versus 838±63, respectively).
Increased energy expenditure and energy loss through feces contribute to long-term body-weight control after RYGB. Enhanced glucose utilization might play a role in long-term improvement in glucose metabolism.
Roux-en-Y胃旁路术（RYGB）已被证明在长期体重减轻和糖尿病缓解方面比其他减肥手术更有效。然而，其机制仍知之甚少。RYGB术后能量代谢的长期变化鲜有报道。
在饮食诱导肥胖（DIO）小鼠模型中研究RYGB对能量代谢的长期影响。
将喂食高脂饮食的DIO小鼠分为两组：RYGB组（n = 8）和假手术组（n = 7），术后继续高脂饮食喂养至12周。每周记录体重和食物摄入量。术后第4、8和12周通过代谢室测量身体成分和能量代谢。术后第12周进行粪便能量测量、腹腔葡萄糖耐量试验和胰岛素耐量试验。
RYGB组术后前3周食物摄入量减少，术后第4周增加至与假手术组相同。术后12周，RYGB组体重下降了36%±3.2%，而假手术组体重增加了16%±2%，与假手术组相比，RYGB组脂肪量显著减少（9.2%±1.5%对30.1%±0.7%）。RYGB组术后第8周的能量消耗显著高于假手术组。与假手术组相比，RYGB组术后第4、8和12周的呼吸交换率分别无变化、降低和升高。粪便能量测量显示，RYGB组小鼠粪便中的能量水平高于假手术组。腹腔葡萄糖耐量试验（AUC分别为1,502±104对2,277±198）和胰岛素耐量试验（AUC分别为524±50对838±63）表明，与假手术组相比，RYGB组的葡萄糖代谢显著改善。
能量消耗增加和粪便能量损失有助于RYGB术后的长期体重控制。葡萄糖利用增强可能在葡萄糖代谢的长期改善中起作用。
