Gastric Bypass Improves Obesity and Glucose Tolerance Independent of Gastric Pouch Size

  • Rui Xu
  • Chenyu Zhu
  • Joseph F. PierreEmail author
  • Deng Ping YinEmail author
Original Contributions



We investigated whether metabolic phenotype improvements following gastric bypass are associated with gastric resection strategy in high-fat diet-induced obese (DIO) mice.

Materials and Methods

We developed the mouse Roux-en-Y gastric bypass (RYGB) model with different gastric pouch sizes: (i) RYGB with a large gastric pouch (RYGB-LP), where the stomach was transected, and the jejunum was anastomosed to the residual forestomach, in which 30% of the stomach is retained. (ii) RYGB with a small remnant gastric pouch (RYGB-SP), where the stomach was transected 0.8 cm distal to the esophagogastric junction, and the jejunum is attached to a small remnant of the forestomach (~ 10% of the stomach). (iii) RYGB without gastric pouch (RYGB-NP), where the jejunum is anastomosed to the lower portion of the esophagus.


Surgical success rate (or 4-week mouse survival rate) of the RYGB-LP, RYGB-SP, and RYGB-NP procedures was 50, 75, and 85%, respectively. Our data demonstrate that all RYGB procedures improved body weight, glucose tolerance, and liver steatosis, compared with untreated DIO mice at 8-week post-surgery. Major surgical complication, such as obstruction at the forestomach, occurred predominantly in RYGB-LP mice, resulting in a higher mortality. Pre- and post-prandial plasma ghrelin levels did not correlate with improved metabolic phenotype after gastric bypass.


We conclude that RYGB with different gastric pouch equally improves obesity and glucose tolerance independent of gastric pouch size and total plasma ghrelin levels in the mouse model of RYGB surgery.


Gastric Sleeve Bariatric surgery Metabolic surgery Ghrelin 


Funding Information

This work was supported in part by the CTSA grant (CTSA TR000430 at the University of Chicago) to DPY and NIH grant DK020595 to the Metabolic Core.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

Statement of Animal Rights/Ethical Approval

All experiments and surgical preparations were performed according to the protocol approved by the University of Chicago Institutional Animal Care and Use Committee (IACUC).


  1. 1.
    Ferrannini E, Camastra S, Gastaldelli A, et al. Beta-cell function in obesity: effects of weight loss. Diabetes. 2004;53(Suppl 3):S26–33.CrossRefGoogle Scholar
  2. 2.
    Heneghan HM, Yimcharoen P, Brethauer SA, et al. Influence of pouch and stoma size on weight loss after gastric bypass. Surgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery. 2012;8:408–15.CrossRefGoogle Scholar
  3. 3.
    Topart P, Becouarn G, Ritz P. Pouch size after gastric bypass does not correlate with weight loss outcome. Obes Surg. 2011;21:1350–4.CrossRefGoogle Scholar
  4. 4.
    O’Connor EA, Carlin AM. Lack of correlation between variation in small-volume gastric pouch size and weight loss after laparoscopic Roux-en-Y gastric bypass. Surgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery. 2008;4:399–403.CrossRefGoogle Scholar
  5. 5.
    Nishie A, Brown B, Barloon T, et al. Comparison of size of proximal gastric pouch and short-term weight loss following routine upper gastrointestinal contrast study after laparoscopic Roux-en-Y gastric bypass. Obes Surg. 2007;17:1183–8.CrossRefGoogle Scholar
  6. 6.
    Saber AA, Elgamal MH, McLeod MK. Bariatric surgery: the past, present, and future. Obes Surg. 2008;18:121–8.CrossRefGoogle Scholar
  7. 7.
    Yin DP, Gao Q, Ma LL, et al. Assessment of different bariatric surgeries in the treatment of obesity and insulin resistance in mice. Ann Surg. 2011;254:73–82.CrossRefGoogle Scholar
  8. 8.
    Howard DD, Caban AM, Cendan JC, et al. Gastroesophageal reflux after sleeve gastrectomy in morbidly obese patients. Surgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery. 2011;7:709–13.CrossRefGoogle Scholar
  9. 9.
    Cummings DE, Weigle DS, Frayo RS, et al. Plasma ghrelin levels after diet-induced weight loss or gastric bypass surgery. N Engl J Med. 2002;346:1623–30.CrossRefGoogle Scholar
  10. 10.
    de Freitas AC, Campos AC, Coelho JC. The impact of bariatric surgery on nonalcoholic fatty liver disease. Current opinion in clinical nutrition and metabolic care. 2008;11:267–74.CrossRefGoogle Scholar
  11. 11.
    Wang Y, Liu J. Plasma ghrelin modulation in gastric band operation and sleeve gastrectomy. Obes Surg. 2009;19:357–62.CrossRefGoogle Scholar
  12. 12.
    Beard JH, Bell RL, Duffy AJ. Reproductive considerations and pregnancy after bariatric surgery: current evidence and recommendations. Obes Surg. 2008;18:1023–7.CrossRefGoogle Scholar
  13. 13.
    Chambers AP, Kirchner H, Wilson-Perez HE, et al. The effects of vertical sleeve gastrectomy in rodents are ghrelin independent. Gastroenterology. 2013;144:50–2. e55CrossRefGoogle Scholar
  14. 14.
    Hatoum IJ, Stylopoulos N, Vanhoose AM, et al. Melanocortin-4 receptor signaling is required for weight loss after gastric bypass surgery. J Clin Endocrinol Metab. 2012;97:E1023–31.CrossRefGoogle Scholar
  15. 15.
    Andrikopoulos S, Blair AR, Deluca N, et al. Evaluating the glucose tolerance test in mice. Am J Physiol Endocrinol Metab. 2008;295:E1323–32.CrossRefGoogle Scholar
  16. 16.
    Stengel A, Goebel M, Wang L, et al. Differential distribution of ghrelin-O-acyltransferase (GOAT) immunoreactive cells in the mouse and rat gastric oxyntic mucosa. Biochem Biophys Res Commun. 2010;392:67–71.CrossRefGoogle Scholar
  17. 17.
    Yimcharoen P, Heneghan HM, Tariq N, et al. Endoscopic stent management of leaks and anastomotic strictures after foregut surgery. Surgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery. 2011;7:628–36.CrossRefGoogle Scholar
  18. 18.
    Seyfried F, Lannoo M, Gsell W, et al. Roux-en-Y gastric bypass in mice--surgical technique and characterisation. Obes Surg. 2012;22:1117–25.CrossRefGoogle Scholar
  19. 19.
    Hao Z, Zhao Z, Berthoud HR, et al. Development and verification of a mouse model for Roux-en-Y gastric bypass surgery with a small gastric pouch. PLoS One. 2013;8:e52922.CrossRefGoogle Scholar
  20. 20.
    Frohman HA, Rychahou PG, Li J, et al. Development of murine bariatric surgery models: lessons learned. J Surg Res. 2018;229:302–10.CrossRefGoogle Scholar
  21. 21.
    Xanthakos SA. Nutritional deficiencies in obesity and after bariatric surgery. Pediatr Clin N Am. 2009;56:1105–21.CrossRefGoogle Scholar
  22. 22.
    Xanthakos SA, Inge TH. Nutritional consequences of bariatric surgery. Curr Opin Clin Nutr Metab Care. 2006;9:489–96.CrossRefGoogle Scholar
  23. 23.
    von Drygalski A, Andris DA. Anemia after bariatric surgery: more than just iron deficiency. Nutr Clin Pract. 2009;24:217–26.CrossRefGoogle Scholar
  24. 24.
    Malin SK, Samat A, Wolski K, et al. Improved acylated ghrelin suppression at 2 years in obese patients with type 2 diabetes: effects of bariatric surgery vs standard medical therapy. Int J Obes. 2013;Google Scholar

Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2020

Authors and Affiliations

  1. 1.Department of SurgeryYichang Central Hospital & Three Gorges University First Clinical CollegeYichangChina
  2. 2.Department of PediatricsUniversity of Tennessee Health Science CenterMemphisUSA
  3. 3.Animal Microsurgery Center, Department of SurgeryUniversity of Chicago School of MedicineChicagoUSA

Personalised recommendations