Microbiota Alters Urinary Bladder Weight and Gene Expression.

Blanka Roje,Till Strowig,Katarina Vilović,Janoš Terzić,Aida Iljazović,Kristian Vlahoviček,Ana Šimić,Anamaria Elek,Lana Sušak,Vinko Palada,Joana Bom

doi:10.3390/microorganisms8030421

Abstract

We studied the effect of microbiota on the transcriptome and weight of the urinary bladder by comparing germ-free (GF) and specific pathogen-free (SPF) housed mice. In total, 97 genes were differently expressed (fold change > ±2; false discovery rate (FDR) p-value < 0.01) between the groups, including genes regulating circadian rhythm (Per1, Per2 and Per3), extracellular matrix (Spo1, Spon2), and neuromuscular synaptic transmission (Slc18a3, Slc5a7, Chrnb4, Chrna3, Snap25). The highest increase in expression was observed for immunoglobulin genes (Igkv1-122, Igkv4-68) of unknown function, but surprisingly the absence of microbiota did not change the expression of the genes responsible for recognizing microbes and their products. We found that urinary bladder weight was approximately 25% lighter in GF mice (p = 0.09 for males, p = 0.005 for females) and in mice treated with broad spectrum of antibiotics (p = 0.0002). In conclusion, our data indicate that microbiota is an important determinant of urinary bladder physiology controlling its gene expression and size.

Highlights

The microbiome is an important determinant of our health
The importance of the urinary bladder microbiome is nicely demonstrated by the modulation of the bladder microbiome by bacillus Calmette– Guérin (BCG), which is successfully used as a bladder cancer therapy [3]
We aimed to identify the effects of the microbiota on the bladder transcriptome by comparing germ-free (GF) mice with mice that harbour normal microbiota [4]

Summary

Introduction

The microbiome is an important determinant of our health. Contrary to the previous belief, the urinary bladder is not sterile. It contains a microbiome, which differs among individuals depending on age, sex, and health status [2]. With the permanent contact with urine as a permissive medium for bacterial growth, the urethra and urinary bladder are likely sites constantly challenged by microbial growth. The role of microbiota in the physiology and pathology of the urinary bladder is not well understood. Besides the urinary microbiome that can directly influence bladder through the urothelium or via metabolites discharged in the urine, the gut microbiota can indirectly influence remote parts of the body including urinary bladder physiology [1]

Objectives

Methods

Findings

Conclusion