Specific Changes in the Mammalian Gut Microbiome as a Biomarker for Oxytocin-Induced Behavioral Changes

Itzhak Dangoor,Vesna Pešić,Leah Reshef,Dušanka Stanić,Uri Gophna

doi:10.2139/ssrn.3770108

Abstract

Prolonged exposure to psychiatric pharmacological agents is often associated with marked gastrointestinal phenomena, including changes in food intake, bowel motility, gastric emptying, and transit time. Those changes are reflected in the gut microbiome composition of the patient and can therefore be objectively measured. This is in contrast to the standard psychiatric evaluation of patients which includes symptoms that are subjectively assessed (i.e. mood, anxiety level, perception, thought disorders, etc.). The association between a drug’s effect on the microbiome and psychiatric symptoms may allow for quantifiable surrogate markers of treatment effectiveness. This is due to levels of specific bacteria that can serve as biomarkers for intake and effectiveness of psychiatric drugs. Here we show substantial microbiome changes that were associated with oxytocin administration and the decreased anxiety/depression-like behaviours it conferred in a rat model of corticosterone-induced stress. Compared to oxytocin, citalopram produced more minor effects on the rats’ microbiome. Alterations in the gut microbiome may therefore reflect the consumption and effectiveness of some psychiatric drugs.

Highlights

Humans are colonized by bacteria, fungi, archaea, and viruses, which are collectively referred to as the microbiome
Most of the microbiome resides in the gut and may be investigated via stool sampling and subsequent metagenomic DNA sequencing
Prolonged exposure to psychiatric pharmacological agents is often associated with marked gastrointestinal phenomena, including changes in food intake, bowel motility, gastric emptying, and transit time [1,2,3]

Summary

Introduction

Humans are colonized by bacteria, fungi, archaea, and viruses, which are collectively referred to as the microbiome. Most of the microbiome resides in the gut and may be investigated via stool sampling and subsequent metagenomic DNA sequencing. Unlike the relatively objective measurement of the microbiota composition, accurate assessment of patients’ therapy adherence and treatment outcomes represent a challenge in psychiatric medical care [4]. This is partly because, for most psychopharmacological agents, compliance and response to treatments are subjectively assessed based on self-reporting and physicians’ evaluations [5,6]. An interesting alternative is having changes in the psychiatric patients’ gut microbiota composition serve as a measurable proxy for monitoring patients’ compliance and the therapeutic effects of some drugs

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Results