How Serotonin Level Fluctuation Affects the Effectiveness of Treatment in Irritable Bowel Syndrome.

Ilmaben S Vahora,Ravi Soni,Nicholas Tsouklidis,Rajat Kumar,Safeera Khan

doi:10.7759/cureus.9871

Abstract

Irritable bowel syndrome (IBS) is one of the most commonly diagnosed functional gastrointestinal (GI) disorders. It affects both men and women. Enteric serotonin (5HT) is responsible for gut motility, secretion, visceral hypersensitivity, and inflammation. The serotonin reuptake transporter (SERT) maintains serotonin levels by regulating its reuptake. An increase in SERT expression causes a decrease in serotonin, which leads to IBS-C (irritable bowel syndrome, constipation-predominant), whereas a decrease in SERT transcription causes an increase in serotonin, which leads to IBS-D (irritable bowel syndrome, diarrhea-predominant). Some factors can alter SERT transcription, such as certain bacteria, inflammation, growth factor, and glucagon-like peptide-1. This shows that 5HT and SERT both have an important role in IBS pathophysiology so that it would be a better subject to target for the treatment aspect of IBS. 5HT3 receptor antagonists are advisable for IBS-D to block the excessive activity of serotonin at the 5HT3 receptor and reduce gut motility. For IBS-C, we prescribe 5HT4 receptor agonists, which promote gut motility. Also, the latest treatment approach, antidepressant drugs TCAs (tricyclic antidepressants) and SSRIs (selective serotonin reuptake inhibitors), are helpful by modulating serotonin levels in the gut. In this literature review, we found that serotonin is one of the main pathophysiological factors for IBS, and we can treat IBS by targeting serotonin function on gut motility.

Highlights

BackgroundIn the United States, almost 10 to 15% of the adult population suffers from irritable bowel syndrome (IBS) symptoms, and out of those, adults that have been diagnosed with the disease are only 5 to 7%
An increase in serotonin reuptake transporter (SERT) expression causes a decrease in serotonin, which leads to Irritable bowel syndrome (IBS)-C, whereas a decrease in SERT transcription causes an increase in serotonin, which leads to IBS with diarrhea (IBS-D)
Some factors can alter SERT transcription, such as certain bacteria, inflammation, growth factor, and glucagon-like peptide-1. This shows that 5HT and SERT both have an important role in IBS pathophysiology so that it would be a better subject to target for the treatment aspect of IBS. 5HT3 receptor antagonists are advisable for IBS-D to block the excessive activity of serotonin at the 5HT3 receptor and reduce gut motility

Summary

Introduction

BackgroundIn the United States, almost 10 to 15% of the adult population suffers from irritable bowel syndrome (IBS) symptoms, and out of those, adults that have been diagnosed with the disease are only 5 to 7%. IBS is one of the most commonly diagnosed disorders in gastroenterology, as well as in primary care practices [1]. According to Rome IV criteria, IBS diagnosed with recurrent abdominal pain is associated with two or more of the following criteria: (a) related to defecation, (b) change in frequency of stool, and (c) change in consistency of stool, at least one day per week in the last three months. There is no single diagnostic test for IBS, with diagnosis mainly being based on symptom presentation. Research is being conducted for the effectiveness of antidepressants for IBS symptom improvement. Researchers found that about 55% of patients treated with selective serotonin reuptake inhibitors (SSRIs) showed improvement in IBS symptoms vs 33% for placebo [6]

Methods

Findings

Discussion

Conclusion