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Topic: Nutrition and the Gut-Liver-Brain Axis

October 2022
Current Hepatology Reports 21(3):1-12

DOI:10.1007/s11901-022-00589-x

Authors:

Chinese University of Hong Kong

The gut-liver brain-axis describes the bidirectional interaction between the gastrointestinal system, the liver, and the central nervous system with involvement of the gut microbiota. Regulated by the intestinal, blood–brain and gut-vascular barrier, the immune system, and the microbially derived molecules that are derived from diet, the nutrition-gut-liver-brain axis has an essential role in a number of diseases. This review will canvass some of the concepts regarding the nutrition-gut-liver-brain axis and focus on common diseases with recent evidence.

Nutrition and the gut-liver-brain axis

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https://doi.org/10.1007/s11901-022-00589-x

NUTRITION (AV KULKARNI, SECTION EDITOR)

Topic: Nutrition andtheGut‑Liver‑Brain Axis

AgnesH.Y.Ho1· SunnyWong2· RashidLui1

Accepted: 24 August 2022

Abstract

The gut-liver brain-axis describes the bidirectional interaction between the gastrointestinal system, the liver, and the central

nervous system with involvement of the gut microbiota. Regulated by the intestinal, blood–brain and gut-vascular barrier,

the immune system, and the microbially derived molecules that are derived from diet, the nutrition-gut-liver-brain axis has

an essential role in a number of diseases. This review will canvass some of the concepts regarding the nutrition-gut-liver-

brain axis and focus on common diseases with recent evidence.

Introduction

Research on the complex interplay between the gastroin-

testinal tract, liver, and the brain has bloomed over recent

decades. There is growing evidence that the bidirectional

[1, 2] gut-liver-brain axis plays an immense role for various

gastrointestinal, liver, and neuropsychiatric diseases.

Although our understanding of the nature and function

of the gut microbiome is still limited, there is emerging evi-

dence of the involvement of microbiota and its eﬀects on the

gut-liver-brain axis [3].

The gut microbiome refers to the collective genomes of

approximately 40 trillion microorganisms in the human gas-

trointestinal (GI) tract [4]. Twin studies have shown that,

in addition to heritable components, diet and drugs are the

major determinants of the gut microbiome [5]. Examples of

currently used therapies targeting pathogenesis involving the

microbiome and gut-brain-liver axis include lactulose and

rifaximin as the treatment for hepatic encephalopathy [6].

In this review, we will canvass some of the concepts regard-

ing the nutrition-gut-liver-brain axis and focus on common

diseases with recent evidence regarding nutrition and the gut-

liver-brain axis including metabolic dysfunction-associated

fatty liver disease (MAFLD), alcoholic liver disease (ALD)/

AUD, irritable bowel syndrome (IBS), and hepatic encepha-

lopathy (HE) and how these developments may potentially

translate into novel therapeutic interventions (Fig.1).

The Gut‑Liver‑Brain Axis

Gut‑Liver Interactions

The bidirectional communication between the gastrointestinal

tract, along with the microbiome and liver, is regulated by the

enterohepatic circulation. Via the portal vein, microorganism-

derived products are transported from the intestine to the liver,

which feedbacks to the intestine through bile acids and antimi-

crobial molecules [1, 7]. Meanwhile, the highly speciﬁc bar-

rier at the intestine acts as the interface to limit dissemination

of pathogenic microorganisms and microorganism-derived

molecules and toxins into the liver, and beyond into the sys-

temic circulation [8]. Disruption of the gut-liver axis is now

thought to be the underlying pathogenic mechanism of many

liver diseases including MAFLD and ALD [1].

Gut‑Brain Interactions

The reciprocity of the gut and the brain is described as the

gut-brain axis (GBA) which modulates major physiologi-

cal and homeostatic functions. The central nervous system

(CNS) is now known to regulate the gut via the hypotha-

lamic–pituitary–adrenal axis (HPA) and the autonomic

nervous system (ANS) [9]. Likewise, the gut modiﬁes the

CNS function by microbiota-derived molecules and neuro-

active molecules such as acetylocholine, GABA, serotonin

This article is part of the Topical Collection on Nutrition

* Rashid Lui

rashidlui@cuhk.edu.hk

1 Prince ofWales Hospital, Shatin, NewTerritories,

HongKong

2 Lee Kong Chian School ofMedicine, Nanyang Technological

University, Headquarters and Clinical Sciences Building, 11

Mandalay Road, Singapore, Singapore

/ Published online: 17 October 2022

Current Hepatology Reports (2022) 21:99–110

Content courtesy of Springer Nature, terms of use apply. Rights reserved.

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Correction to: Efficacy of a low-FODMAP diet in adult irritable bowel syndrome: a systematic review and meta-analysis

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EUR J NUTR

p>The original version of this article unfortunatelȳ contained a mistake. The X-axis labels (‘Favours [control]’ and ‘Favours [experimental]’) were presented in the wrong order in Fig. 4. The corrected Fig. 4 is given below. (Figure presented.).</p

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