title: The Effects of Sleeve Gastrectomy and Gastric Bypass on Branched-Chain Amino Acid Metabolism 1 Year After Bariatric Surgery.
abstract: Weight loss, early after Roux-en-Y gastric bypass (GB) surgery, is associated with reduced concentrations of plasma branched-chain amino acids (BCAAs) and improved insulin sensitivity. Herein, we evaluated whether changes in BCAAs and insulin sensitivity persist with weight stabilization (1 year) after GB or sleeve gastrectomy (SG).
  
  
  
  We prospectively examined 22 severely obese patients (mean age 40.6 ± 2.1 years, BMI 38.8 ± 1.3 kg/m(2), and 59.1 % female) who underwent SG (n = 12) or GB (n = 10) for morbid obesity. Body fat composition was measured with dual X-Ray absorptiometry and abdominal fat volume with computed tomography. BCAAs and acylcarnitines were profiled using liquid chromatography with tandem mass spectrometry. Insulin resistance was calculated using the homeostasis model assessment for insulin resistance (HOMA-IR) formula.
  
  
  
  At 1-year follow-up, the decrease in BMI, body weight, total fat mass (TFM), fat free mass, and visceral adipose tissue (VAT) was similar between SG and GB. HOMA-IR was associated with BCAA concentrations, and both were decreased equally in both surgical groups. In multivariate analysis with BCAAs, TFM, and VAT as independent factors, only VAT remained significantly associated with insulin resistance.
  
  
  
  The metabolic benefits from bariatric surgery, including the changes in BCAA profile, are comparable between SG and GB. The reduction in BCAAs and improvement in the AC profiles after bariatric surgery persists up to 12 months after surgery and may not be surgical related but is influenced primarily by the amount of weight loss, in particular the reduction in visceral adiposity.
authors.affiliation: Department of Endocrinology, Singapore General Hospital, The Academia Level 3, 20 College Road, Singapore, 169856, Singapore. tan.hong.chang@sgh.com.sg.
authors.forename: Hong Chang
authors.initials: HC
authors.lastname: Tan
authors.affiliation: Department of Medicine, National University of Singapore, Singapore, Singapore.|Cardiovascular Metabolic Program, DUKE-NUS Graduate Medical School, Singapore, Singapore.
authors.forename: Chin Meng
authors.initials: CM
authors.lastname: Khoo
authors.affiliation: Department of Endocrinology, Singapore General Hospital, The Academia Level 3, 20 College Road, Singapore, 169856, Singapore.
authors.forename: Matthew Zhen-Wei
authors.initials: MZ
authors.lastname: Tan
authors.affiliation: Cardiovascular Metabolic Program, DUKE-NUS Graduate Medical School, Singapore, Singapore.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Kovalik
authors.affiliation: The Endocrine Clinic, Mount Elizabeth Novena Specialist Centre, Singapore, Singapore.
authors.forename: Alvin Choong Meng
authors.initials: AC
authors.lastname: Ng
authors.affiliation: Department of Upper GI and Bariatric Surgery, Singapore General Hospital, Singapore, Singapore.
authors.forename: Alvin Kim Hock
authors.initials: AK
authors.lastname: Eng
authors.affiliation: Department of Clinical Research, Singapore General Hospital, Singapore, Singapore.
authors.forename: Oi Fah
authors.initials: OF
authors.lastname: Lai
authors.affiliation: Cardiovascular Metabolic Program, DUKE-NUS Graduate Medical School, Singapore, Singapore.
authors.forename: Jian Hong
authors.initials: JH
authors.lastname: Ching
authors.affiliation: Department of Endocrinology, Singapore General Hospital, The Academia Level 3, 20 College Road, Singapore, 169856, Singapore.
authors.forename: Kwang Wei
authors.initials: KW
authors.lastname: Tham
authors.affiliation: Advanced Laparoscopic Surgery, Gleneagles Hospital, Singapore, Singapore.
authors.forename: Shanker
authors.initials: S
authors.lastname: Pasupathy
mesh_terms: D015502:Absorptiometry, Photon; D000328:Adult; D000597:Amino Acids, Branched-Chain / Q000097:blood*; D001823:Body Composition; D005260:Female; D005743:Gastrectomy / Q000379:methods; D015390:Gastric Bypass / Q000379:methods; D006801:Humans; D006949:Hyperlipidemias / Q000145:classification / Q000150:complications*; D007333:Insulin Resistance; D050152:Intra-Abdominal Fat / Q000378:metabolism; D008297:Male; D009767:Obesity, Morbid / Q000150:complications / Q000601:surgery*; D011184:Postoperative Period; D015431:Weight Loss
chemical_list: D000597:Amino Acids, Branched-Chain
keywords: Branched-chain amino acids; Gastric bypass; Insulin resistance; Sleeve gastrectomy; Visceral adipose tissue