Adipokine Response in Diabetics and Nondiabetics Following the Roux-en-Y Gastric Bypass: A Preliminary Study Bryan A. Whitson, M.D.,* Daniel B. Leslie, M.D.,* Todd A. Kellogg, M.D.,* Michael A. Maddaus, M.D.,* Henry Buchwald, M.D., Ph.D.,* Charles J. Billington, M.D.,† and Sayeed Ikramuddin, M.D.* ,1 *University of Minnesota Department of Surgery, Division of Gastrointestinal Surgery, and †University of Minnesota Department of Medicine, Section of Endocrinology and Metabolism, Center for Diabetes Research, Minneapolis, Minnesota Submitted for publication January 8, 2007 Introduction. The adipocyte influences eating be- havior and metabolism via cytokine secretion. We re- port our findings of adipokine secretion in a cohort of diabetic and nondiabetic morbidly obese patients be- fore and after Roux-en-Y gastric bypass (RYGB). Methods. Ten morbidly obese subjects who under- went uncomplicated RYGB were studied: five were di- abetic and nine were female. Nonfasting plasma levels of adiponectin, resistin, leptin, and tumor necrosis factor-alpha were determined preoperatively and 6 mo postoperatively. C-reactive protein (CRP) was fol- lowed as a marker of the metabolic syndrome. Results. The patient age was 42  11 y, and the preop- erative BMI was 50  6 kg/m 2 . The 6 mo BMI fell to 33  5 kg/m 2 (P < 0.0001), and there were no differences be- tween diabetics and nondiabetics with respect to amount of weight loss. In nondiabetic patients, there were significant increases compared with preoperative levels for adiponectin, resistin, and tumor necrosis fac- tor-alpha; leptin was significantly decreased while CRP was unchanged. CRP and leptin levels were both signif- icantly lower (P < 0.05), while all other protein levels were unchanged in diabetic patients. Conclusions. At 6 mo postoperation, RYGB signifi- cantly altered most adipokine levels for nondiabetic pa- tients. Only CRP and leptin were changed in diabetic patients. All patients lost a significant amount of weight over 6 mo, suggesting a different metabolic effect between nondiabetic and diabetic patients after RYGB. © 2007 Elsevier Inc. All rights reserved. Key Words: morbid obesity; diabetic; gastric bypass; adipokine. INTRODUCTION The adipocyte influences eating behavior and metab- olism via cytokine secretion. A complex interaction be- tween cytokines and hormones within the cellular mi- lieu controls insulin sensitivity and energy usage. Adipokine secretion is related to total fat mass [1–3] and, therefore, it is expected that the plasma level of each adipokine should change after an operation for morbid obesity, such as the Roux-en-Y gastric bypass (RYGB). The gastric bypass results in a very high resolution rate of type 2 diabetes mellitus (T2DM) [4, 5] in comparison with restrictive procedures. Outcomes following the gastric bypass are different for diabetics in comparison with nondiabetics. Diabet- ics on the whole lose less weight than nondiabetics in long-term follow-up. Further, the weight loss appears to correlate inversely to the severity of the disease [5]. Interestingly, the phenomenon of post-bypass hypogly- cemia is rarely observed in diabetics, in our personal experience. Differential responses by which the adipokines re- spond to RYGB in relation to diabetes status may suggest a mechanism for these observations. This pre- liminary study is designed to ask some basic questions of the complex interaction of obesity, determinants of insulin sensitivity, and weight loss surgery. Of partic- ular interest is an attempt to identify and characterize hormonal changes associated with T2DM status in re- sponse to operative status after RYGB. MATERIALS AND METHODS The Institutional Review Board at the University of Minnesota approved this study (no. 0302M41801). A prospective nonrandom- ized observational study of patients undergoing primary Roux-en-Y 1 To whom correspondence and reprint requests should be ad- dressed at Department of Surgery, University of Minnesota, MMC 195, 420 Delaware St. SE, Minneapolis, MN 55455. E-mail: ikram001@umn.edu. Journal of Surgical Research 142, 295–300 (2007) doi:10.1016/j.jss.2007.03.036 295 0022-4804/07 $32.00 © 2007 Elsevier Inc. All rights reserved.