Abstract:
Roux-en-Y Gastric Bypass may be associated with an alteration of protein bioavailability in relation to intestinal remodeling. Our study aimed to test this hypothesis by Roux-en-Y Gastric Bypass. Diet-induced obese rats underwent Roux-en-Y Gastric Bypass surgery (RYGB rats) while a Sham-operated control group was used. All rats received a 15N-labeled protein meal 1 or 3 months after surgery and were euthanized 6h later. Protein digestibility, 15N recovered in organs and urea pool, fractional protein synthesis rate, and intestinal morphometry were assessed. Protein digestibility was similar in all groups (94.2±0.3%). The small intestine was hypertrophied in RYGB rats 1 month after surgery, weighing 9.1±0.2g vs. 7.0±0.3g in Sham rats (P = 0.003). Villus height and crypt depth were increased in the alimentary limb and ileum of RYGB rats. However, Roux-en-Y Gastric Bypass had no impact on the fractional synthesis rate. In the gastrointestinal tract, 15N retention only differed in the ileal mucosa and was higher in RYGB rats at 1 month (0.48±0.2% vs. 0.3±0.09%, P = 0.03). 15N recovery from the liver, muscle, and skin was lower in RYGB rats at 1 month. 15N recovery from urinary and plasma urea was higher in RYGB rats at both times, resulting in increased total deamination (13.2±0.9% vs. 10.1±0.5%, P<0.01). This study showed that Roux-en-Y Gastric Bypass did not affect protein digestibility. Dietary nitrogen sequestration was transitorily and moderately diminished in several organs. This was associated with a sustained elevation of postprandial deamination after Roux-en-Y Gastric Bypass, whose mechanisms merit further studies.
摘要:
Roux-en-Y胃旁路可能与肠道重塑相关的蛋白质生物利用度的改变有关。我们的研究旨在通过Roux-en-Y胃旁路术检验这一假设。饮食诱导的肥胖大鼠接受Roux-en-Y胃旁路手术(RYGB大鼠),而使用假手术对照组。所有大鼠在手术后1或3个月接受15N标记的蛋白质餐,并在6小时后实施安乐死。蛋白质消化率,在器官和尿素池中回收15N,蛋白质合成率,和肠道形态测量进行了评估。所有组的蛋白质消化率相似(94.2±0.3%)。RYGB大鼠术后1个月小肠肥大,称重9.1±0.2gvs.假手术大鼠7.0±0.3g(P=0.003)。RYGB大鼠消化道和回肠的绒毛高度和隐窝深度增加。然而,Roux-en-Y胃旁路术对分数合成速率没有影响。在胃肠道,15N保留仅在回肠粘膜中有所不同,在1个月时RYGB大鼠中更高(0.48±0.2%vs.0.3±0.09%,P=0.03)。15N从肝脏恢复,肌肉,1个月时RYGB大鼠皮肤较低。在两种情况下,RYGB大鼠从尿和血浆尿素中恢复的15N较高,导致总脱氨增加(13.2±0.9%与10.1±0.5%,P<0.01)。这项研究表明,Roux-en-Y胃旁路不影响蛋白质的消化率。在几个器官中,饮食固氮暂时和中度减少。这与Roux-en-Y胃旁路术后餐后脱氨的持续升高有关,其机制值得进一步研究。