Obesity Surgery

, Volume 22, Issue 10, pp 1648–1657

Gut Hormones and Leptin: Impact on Energy Control and Changes After Bariatric Surgery—What the Future Holds

Review

Abstract

Obesity is now considered the new world epidemic. In an attempt to face this menace to public health, several treatments, apart from the traditional nutritional modification and oral medication, have been introduced, among them bariatric surgery and gut hormone-based treatments. The gastrointestinal (GI) tract is a powerful endocrine organ, releasing active peptides and influencing appetite and glycaemic control. Alteration of the GI tract, in ways that exaggerate the secretion and levels of the gut hormones, creates a new functional equilibrium that further contributes to weight loss. The purpose of this review is to explore the mechanisms that drive this gut hormone-derived body regulation, as well as the changes that occur to them after bariatric surgery. Close to that, leptin, a hormone secreted by adipose tissue will be analysed, as its pathways are closely related to those of the gut hormones. Gut hormones are strongly implicated in energy control, and various effects of bariatric surgery in weight loss are directly related to the alteration of the levels of these hormones.

Keywords

Gut peptides Bariatric surgery Energy control 

Abbreviations

AgRP

Agouti-related peptide

AMPK

AMP-activated protein kinase

ARC

Arcuate nucleus

α-MSH

Alpha-melanocyte-stimulating hormone

BMI

Body mass index

CNS

Central nervous system

CART

Cocaine- and amphetamine-regulated transcript

DPP4

Dipeptidyl peptidase-4

GHS-R

Growth hormone secretagogue receptor

GIP

Glucose-dependent insulinotropic peptide

GLP-1

Glucagon-like peptide-1

HbA1c

Glycated haemoglobin

HOMA-IR

Homeostasis assessment model of insulin resistance

NPY

Neuropeptide Y

NTS

Nucleus of the solitary tract

OXM

Oxyntomodulin

POMC

Pro-opiomelanocortin

PP

Pancreatic polypeptide

PVN

Paraventricular nucleus

PYY(3–36)

Peptide YY(3–36)

RYGB

Roux-en-Y gastric bypass

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© Springer Science + Business Media, LLC 2012

Authors and Affiliations

  1. 1.Barts and the London School of MedicineLondonUK
  2. 2.Experimetal Pathology, Conway Institute, School of Medicine and Medical SciencesUniversity College DublinDublinIreland
  3. 3.Barts and the London HospitalLondonUK

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