Tan Hong Chang, Hsu Jean W, Tai E Shyong, Chacko Shaji, Kovalik Jean-Paul, Jahoor Farook
Department of Endocrinology, Singapore General Hospital, Singapore 169608, Singapore.
Children's Nutrition Research Center, Agricultural Research Service, U.S. Department of Agriculture, and Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
Antioxidants (Basel). 2024 Aug 9;13(8):967. doi: 10.3390/antiox13080967.
Glycine is deficient in individuals with obesity but improves following bariatric surgery. Glycine deficiency could impair glutathione (GSH) synthesis and worsen oxidative stress. We examined the impact of obesity-associated glycine deficiency and bariatric surgery on GSH synthesis. Twenty-one participants with severe obesity and twenty-one healthy weight controls were recruited. [1,2-C] glycine was infused to measure the erythrocyte (RBC) GSH synthesis rate. Participants with obesity underwent bariatric surgery, and 19 were restudied six months post-surgery. Compared to healthy weight controls, individuals with obesity had significantly lower concentrations of RBC GSH (2.43 ± 0.23 vs. 2.63 ± 0.26 mmol/L, < 0.01). However, there were no differences in GSH fractional synthesis rate [78.0 (51.4-123.7) vs. 76.9 (49.3-110.1) % pool/day, = 0.58] or absolute synthesis rate [1.85 (1.25-3.32) vs. 1.92 (1.43-3.03) mmol/L RBC/day, = 0.97]. Despite a post-surgery increase in glycine concentration, no statistically significant changes in RBC GSH concentration or synthesis rates were detected. Further, the significant correlation between plasma glycine and RBC GSH concentration at baseline (r = 0.46, < 0.01) was also lost following bariatric surgery. GSH concentration was significantly lower in participants with obesity, but bariatric surgery did not significantly increase GSH concentrations or synthesis rates.
肥胖个体存在甘氨酸缺乏，但在减肥手术后有所改善。甘氨酸缺乏可能会损害谷胱甘肽（GSH）的合成并加重氧化应激。我们研究了肥胖相关的甘氨酸缺乏和减肥手术对GSH合成的影响。招募了21名严重肥胖参与者和21名健康体重对照者。注入[1,2-C]甘氨酸以测量红细胞（RBC）GSH合成率。肥胖参与者接受了减肥手术，其中19人在术后6个月再次接受研究。与健康体重对照者相比，肥胖个体的RBC GSH浓度显著更低（2.43±0.23 vs. 2.63±0.26 mmol/L，<0.01）。然而，GSH的分数合成率[78.0（51.4 - 123.7）vs. 76.9（49.3 - 110.1）%池/天，P = 0.58]或绝对合成率[1.85（1.25 - 3.32）vs. 1.92（1.43 - 3.03）mmol/L RBC/天，P = 0.97]没有差异。尽管术后甘氨酸浓度有所增加，但未检测到RBC GSH浓度或合成率有统计学显著变化。此外，减肥手术后，基线时血浆甘氨酸与RBC GSH浓度之间的显著相关性（r = 0.46，<0.01）也消失了。肥胖参与者的GSH浓度显著更低，但减肥手术并未显著增加GSH浓度或合成率。
