Nicholas Stylopoulos is a Principal investigator at the Division of Endocrinology and an Assistant Professor at Harvard Medical School. His laboratory is part of the Center for Basic and Translational Obesity Research and focuses on the mechanisms by which weight loss surgery affects energy balance.

The Center for Basic and Translational Obesity Research is an exciting new research program at the Division of Endocrinology at Children’s Hospital Boston and Harvard Medical School, whose goal is to improve our understanding of how people become obese or suffer from complications of obesity, and to help translate research findings into better treatments. The Director of the Center is Dr. Joel HirschhornDr. Nada Kalaany is a Principal Investigator at the Center.

The Stylopoulos laboratory uses many gastrointestinal weight loss surgery rodent models to study weight loss procedures (e.g., Roux-en-Y gastric bypass, sleeve gastrectomy, gastric banding and other). These models represent a powerful, novel, translational and clinically relevant model system to study regulation of energy balance and metabolic function. They offer a unique opportunity to unravel mechanisms underlying the beneficial effects of surgery on body weight, metabolism, glucose homeostasis, inflammation and cancer.

By “reverse engineering” the mechanisms by which weight loss surgery induces weight loss and resolution of diabetes and other metabolic complications, we will be able to develop less invasive approaches that will utilize the same effective mechanisms without the invasiveness of surgery. Thus, we will eventually “bypass the bypass” and we will be able to increase the number of treatment options and offer less-invasive options that will allow the widespread use in many categories of patients with obesity, including children and adolescents.


Publications powered by Harvard Catalyst Profiles

  1. Effect of Diet versus Gastric Bypass on Metabolic Function in Diabetes. N Engl J Med. 2020 12 10; 383(24):2391-2392. View abstract
  2. Endoscopic ultrasound-guided sampling and profiling of portal circulation in human patients for metabolic research studies and biomarker assessment. Am J Physiol Gastrointest Liver Physiol. 2020 11 01; 319(5):G584-G588. View abstract
  3. Nonalcoholic fatty liver disease and portal hypertension. Explor Med. 2020; 1:149-169. View abstract
  4. Portal Venous Metabolite Profiling After RYGB in Male Rats Highlights Changes in Gut-Liver Axis. J Endocr Soc. 2020 Feb 01; 4(2):bvaa003. View abstract
  5. Differential Metabolomic Signatures in Patients with Weight Regain and Sustained Weight Loss After Gastric Bypass Surgery: A Pilot Study. Dig Dis Sci. 2020 04; 65(4):1144-1154. View abstract
  6. Gastrointestinal Hormone Profiles Associated With Enteral Nutrition Tolerance and Gastric Emptying in Pediatric Critical Illness: A Pilot Study. JPEN J Parenter Enteral Nutr. 2020 03; 44(3):472-480. View abstract
  7. Intestine-Specific Overexpression of LDLR Enhances Cholesterol Excretion and Induces Metabolic Changes in Male Mice. Endocrinology. 2019 04 01; 160(4):744-758. View abstract
  8. The Feasibility of Examining the Effects of Gastric Bypass Surgery on Intestinal Metabolism: Prospective, Longitudinal Mechanistic Clinical Trial. JMIR Res Protoc. 2019 Jan 24; 8(1):e12459. View abstract
  9. Publisher Correction: Inactivating hepatic follistatin alleviates hyperglycemia. Nat Med. 2018 Oct; 24(10):1628. View abstract
  10. Time-Dependent Molecular Responses Differ between Gastric Bypass and Dieting but Are Conserved Across Species. Cell Metab. 2018 08 07; 28(2):310-323.e6. View abstract
  11. Inactivating hepatic follistatin alleviates hyperglycemia. Nat Med. 2018 07; 24(7):1058-1069. View abstract
  12. Nonalcoholic fatty liver disease and gastric bypass surgery regulate serum and hepatic levels of pyruvate kinase isoenzyme M2. Am J Physiol Endocrinol Metab. 2018 10 01; 315(4):E613-E621. View abstract
  13. Critical role for arginase 2 in obesity-associated pancreatic cancer. Nat Commun. 2017 08 14; 8(1):242. View abstract
  14. Reversible hyperphagia and obesity in rats with gastric bypass by central MC3/4R blockade. Obesity (Silver Spring). 2014 Aug; 22(8):1847-53. View abstract
  15. GLP-1 receptor signaling is not required for reduced body weight after RYGB in rodents. Am J Physiol Regul Integr Comp Physiol. 2014 Mar 01; 306(5):R352-62. View abstract
  16. Reprogramming of intestinal glucose metabolism and glycemic control in rats after gastric bypass. Science. 2013 Jul 26; 341(6144):406-10. View abstract
  17. Sleeve gastrectomy and Roux-en-Y gastric bypass exhibit differential effects on food preferences, nutrient absorption and energy expenditure in obese rats. Int J Obes (Lond). 2012 Nov; 36(11):1396-402. View abstract
  18. Isolated duodenal exclusion increases energy expenditure and improves glucose homeostasis in diet-induced obese rats. Am J Physiol Regul Integr Comp Physiol. 2012 Nov 15; 303(10):R985-93. View abstract
  19. Melanocortin-4 receptor signaling is required for weight loss after gastric bypass surgery. J Clin Endocrinol Metab. 2012 Jun; 97(6):E1023-31. View abstract
  20. Resting energy expenditure and energetic cost of feeding are augmented after Roux-en-Y gastric bypass in obese mice. Endocrinology. 2012 May; 153(5):2234-44. View abstract
  21. Probing the mechanisms of the metabolic effects of weight loss surgery in humans using a novel mouse model system. J Surg Res. 2013 Jan; 179(1):e91-8. View abstract
  22. Mechanisms of bariatric surgery and implications for the development of endoluminal therapies for obesity. Gastrointest Endosc. 2009 Dec; 70(6):1167-75. View abstract
  23. Roux-en-Y gastric bypass enhances energy expenditure and extends lifespan in diet-induced obese rats. Obesity (Silver Spring). 2009 Oct; 17(10):1839-47. View abstract
  24. An endoluminal sleeve induces substantial weight loss and normalizes glucose homeostasis in rats with diet-induced obesity. Obesity (Silver Spring). 2008 Dec; 16(12):2585-92. View abstract
  25. Towards scarless surgery: an endoscopic ultrasound navigation system for transgastric access procedures. Comput Aided Surg. 2007 Nov; 12(6):311-24. View abstract
  26. Assessing technical skill in surgery and endoscopy: a set of metrics and an algorithm (C-PASS) to assess skills in surgical and endoscopic procedures. Surg Innov. 2007 Jun; 14(2):113-21. View abstract
  27. EUS with CT improves efficiency and structure identification over conventional EUS. Gastrointest Endosc. 2007 May; 65(6):866-70. View abstract
  28. Towards scarless surgery: an endoscopic-ultrasound navigation system for transgastric access procedures. Med Image Comput Comput Assist Interv. 2006; 9(Pt 1):445-53. View abstract
  29. Intact Leptin Signaling Is Required for Changes in Food Intake After Roux-en-Y Gastric Bypass in Rats. Digestive Disease Week, Chicago, IL, USA. 2005. View abstract
  30. Changes in serum ghrelin predict weight loss after Roux-en-Y gastric bypass in rats. Surg Endosc. 2005 Jul; 19(7):942-6. View abstract
  31. The history of hiatal hernia surgery: from Bowditch to laparoscopy. Ann Surg. 2005 Jan; 241(1):185-93. View abstract
  32. Simulated laparoscopy using a head-mounted display vs traditional video monitor: an assessment of performance and muscle fatigue. Surg Endosc. 2005 Mar; 19(3):406-11. View abstract
  33. Computer-enhanced laparoscopic training system (CELTS): bridging the gap. Surg Endosc. 2004 May; 18(5):782-9. View abstract
  34. Robotics and ergonomics. Surg Clin North Am. 2003 Dec; 83(6):1321-37. View abstract
  35. Histologic characteristics of laparoscopic saline-enhanced electrosurgery of liver and splenic injuries. Surg Endosc. 2003 Nov; 17(11):1739-43. View abstract
  36. A software based implementation for evaluating surgical performance using kinematic analysis. 2003. View abstract
  37. CELTS: a clinically-based Computer Enhanced Laparoscopic Training System. Stud Health Technol Inform. 2003; 94:336-42. View abstract
  38. Paraesophageal hernia: when to operate? Adv Surg. 2003; 37:213-29. View abstract
  39. A cost--utility analysis of treatment options for inguinal hernia in 1,513,008 adult patients. Surg Endosc. 2003 Feb; 17(2):180-9. View abstract
  40. Paraesophageal hernias: operation or observation? Ann Surg. 2002 Oct; 236(4):492-500; discussion 500-1. View abstract
  41. Development of achalasia secondary to laparoscopic Nissen fundoplication. J Gastrointest Surg. 2002 May-Jun; 6(3):368-76; discussion 377-78. View abstract
  42. Measurement of in-vivo force response of intra-abdominal soft tissues for surgical simulation. Stud Health Technol Inform. 2002; 85:514-9. View abstract
  43. How accurate is computed tomography in predicting the real size of adrenal tumors? A retrospective study. Arch Surg. 1997 Jul; 132(7):740-3. View abstract
  44. Anterior, posterior, or laparoscopic approach for the management of adrenal diseases? Am J Surg. 1997 Feb; 173(2):120-5. View abstract
  45. Adrenaloma: a call for more aggressive management. World J Surg. 1996 Sep; 20(7):788-92; discussion 792-3. View abstract
  46. Oncocytic differentiation in salivary gland tumours. J Laryngol Otol. 1995 Jun; 109(6):569-71. View abstract