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Bariatric Surgery

Bilio-enteric flow and plasma concentrations of bile acids after gastric bypass and sleeve gastrectomy

International Journal of Obesity volume 44, pages 1872–1883 (2020)Cite this article

Subjects

Abstract

Background/objectives

Bile acids in plasma are elevated after bariatric surgery and may contribute to metabolic improvements, but underlying changes in bile flow are poorly understood. We assessed bilio-enteric flow of bile and plasma bile concentrations in individuals with Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) surgery compared with matched non-surgical controls (CON).

Subjects/methods

Fifteen RYGB, 10 SG and 15 CON underwent 99Tc-mebrofenin cholescintigraphy combined with intake of a high-fat 111In-DTPA-labelled meal and frequent blood sampling. A 75Se-HCAT test was used to assess bile acid retention.

Results

After RYGB, gallbladder filling was decreased (p = 0.045 versus CON), basal flow of bile into the small intestine increased (p = 0.005), bile acid retention augmented (p = 0.021) and basal bile acid plasma concentrations elevated (p = 0.009). During the meal, foods passed unimpeded through the gastric pouch resulting in almost instant postprandial mixing of bile and foods, but the postprandial rise in plasma bile acids was brief and associated with decreased overall release of fibroblast growth factor-19 (FGF-19) compared with CON (p = 0.033). After SG, bile flow and retention were largely unaltered (p > 0.05 versus CON), but gastric emptying was accelerated (p < 0.001) causing earlier mixture of bile and foods also in this group. Neither basal nor postprandial bile acid concentrations differed between SG and CON.

Conclusions

Bilio-enteric bile flow is markedly altered after RYGB resulting in changes in plasma concentrations of bile acids and FGF-19, whereas bile flow and plasma concentrations are largely unaltered after SG.

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Fig. 1: Representative examples of gamma camera images during cholescintigraphy with radiolabelled fatty meal in participants with Roux-en-Y gastric bypass (RYGB) (row 1), sleevegastrectomy (SG) (row 2) and non-surgical control (CON) (row 3).
Fig. 2: Retentions of radiolabelled bile and food markers in participants with Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG) and unoperated individuals (CON).
Fig. 3: Plasma concentrations of bile acids, FGF-19, triglycerides, and gut hormones at fasting and in response to the fatty meal in participants with Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and unoperated individuals (CON).

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Acknowledgements

We thank Alis Andersen (Department of Endocrinology, Hvidovre Hospital, Denmark), Rie Pedersen, Heidi Sødahl-Borresø, Trine Huss and Katrine Marie Lyngby (Department of Clinical Physiology and Nuclear Medicine, Centre for Functional Imaging and Research, Hvidovre Hospital, Hvidovre, Denmark), Lene Brus Albæk (Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark) and Marianne Falk and Lene Vibeke Jespersen (Department of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark) for technical assistance.

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Authors and Affiliations

  1. Department of Endocrinology, Hvidovre Hospital, Hvidovre, Denmark

    Aleksander Eiken, Markus Eiken, Maria S. Svane, Kirstine N. Bojsen-Møller, Nils B. Jørgensen, Sten Madsbad & Carsten Dirksen

  2. Department of Clinical Physiology and Nuclear Medicine, Centre for Functional Imaging and Research, Hvidovre Hospital, Hvidovre, Denmark

    Stefan Fuglsang & Jan L. Madsen

  3. NNF Center for Basic Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark

    Rune E. Kuhre, Samuel A. J. Trammell, Jens S. Svenningsen & Jens J. Holst

  4. Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark

    Rune E. Kuhre, Nicolai J. Wewer Albrechtsen & Jens J. Holst

  5. NNF Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark

    Nicolai J. Wewer Albrechtsen

  6. Department. of Clinical Biochemistry, Rigshospitalet, Copenhagen, Denmark

    Nicolai J. Wewer Albrechtsen, Svend H. Hansen & Jens F. Rehfeld

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  1. Aleksander Eiken
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Correspondence to Carsten Dirksen.

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The study was supported by the Novo Nordisk Foundation (NNF16OC0022700) and the Hvidovre and Amager Hospital Research Foundation. None of the authors have any conflict of interest to declare.

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Eiken, A., Fuglsang, S., Eiken, M. et al. Bilio-enteric flow and plasma concentrations of bile acids after gastric bypass and sleeve gastrectomy. Int J Obes 44, 1872–1883 (2020). https://doi.org/10.1038/s41366-020-0578-7

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