Cardio-Metabolic Disease

The beneficial cardiovascular effects of bariatric surgery in obesity and diabetes

Fig. 1: Research Group on Cardio-Metabolic Disease
Figure 1. Research Group on Cardio-Metabolic Disease. From left to right: Riccardo Urbanet, PhD; Michael Engeli, BSc; Petia Doytcheva, MSc; Elisabeth Sekli, MSc; Sylvie Briand, PhD; Prof. Thomas Lüscher MD and Elena Osto MD, PhD, scientific guest.

Obesity and diabetes are associated with increased cardiovascular risk and mortality. Among different therapeutic approaches, bariatric surgery, especially Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) seems to be the most effective procedure, able to achieve sustained and substantial body weight (BW) loss, improving diabetes and other co-morbidities, and thus eventually reducing cardiovascular mortality. The mechanisms of action of bariatric surgery are multiple and in part independent from body weight loss. High density lipoprotein cholesterol (HDL-C) but also changes in the concentrations of gut hormones, in particular glucagon-like peptide-1 (GLP-1) and bile acids might be crucial contributors to the cardiovascular benefits after RYGB.

Fig. 2: Beneficial effects of RYGB
Figure 2. We recently showed that in a rat model, but also in morbidly obese patients, higher plasma levels of GLP-1 were associated with increased aortic NO bioavailability, improved endothelium-dependent relaxation and normalized endothelium-protective properties of HDL after RYGB (from Osto E. et al.. Circ. 2015.).

Our ongoing research aims to understand how bile acids and GLP-1 analogs, which are already used in clinical practice as antidiabetic and weight-lowering drugs, mediate the improved endothelial and HDL functions after bariatric surgery. Hence, our findings will generate clinically relevant results that may help to design novel therapeutic strategies against morbid obesity and in particular its severe cardiovascular risk.

The research group on Cardio-Metabolic Disease pursues translational projects, which combine a major part of clinical research in patients and parallel experiments in rodent models of bariatric surgery. Our research group can count on a unique network with colleagues working abroad but also locally joining forces in the fields of cardiology, bariatric surgery, endocrinology, nutrition and metabolic signaling.  Among others, we have currently successful collaborations with the Institute of Veterinary Physiology, UZH, led by Prof. Thomas Lutz; the Institute of Clinical Chemistry USZ, led by Prof. Arnold von Eckardstein and with the Laboratory of Nutritional Research-ETH, led by Prof. Christian Wolfrum.

References:

  1. Osto E, Doytcheva P, Corteville C, Bueter M, Dörig C, Stivala S, Buhmann H, Colin S, Rohrer L, Hasballa R, Tailleux A, Wolfrum C, Tona F, Manz J, Vetter D, Spliethoff K, Vanhoutte PM, Landmesser U, Pattou F, Staels B, Matter CM, Lutz TA, Lüscher TF. Rapid and body weight-independent improvement of endothelial and HDL function after Roux-en-Y gastric bypass: role of glucagon-like peptide-1. Circulation. 2015; 131: 871-81.
  2. Brown JD. Bariatric surgery: "Roux"-minating on endothelial cell and high-density lipoprotein function. Circulation 2015; 131: 845-7.