Bacillus clausii effect on gene expression pattern in small bowel mucosa using DNA microarray analysis.
BACKGROUND
Probiotics are widely used for the cure or prevention of several clinical conditions. However, clinical decisions need to be substantiated by an analysis of the complex bacteria-host interplay in the intestinal lumen.


OBJECTIVE
To identify the gene expression pattern induced by Bacillus clausii in the intestinal mucosa of healthy individuals.


METHODS
Six male patients (mean age 38+/-5 years) affected by endoscopically confirmed mild oesophagitis were treated for one month with esomeprazole, and were randomly selected to receive or not B. clausii (groups I and II, respectively). Duodenal biopsies were taken pre and post-treatment to identify the modification of gene expression, using the GeneChip Human U133A array. To validate the microarray analysis, real-time reverse transcriptase-polymerase chain reaction (PCR) of five target genes was performed.


RESULTS
After B. clausii administration, a total of 158 and 265 genes were up and downregulated, respectively. Quantitative PCR confirmed the microarray data. B. clausii mainly affected the expression of genes involved in immune response and inflammation, apoptosis and cell growth, cell differentiation, cell-cell signalling, cell adhesion, signal transcription and transduction.


CONCLUSIONS
Our data represent the first global analysis of B. clausii effects on the gene expression profile in normal intestine, and provide the basis to identify the mechanisms by which these agents interact with the host and exert their beneficial effects. Future studies are needed to clarify the B. clausii-induced gene pattern in the clinical disorders in which probiotics have proved to be effective.
Di Caro
Simona
S
Department of Gastroenterology, Catholic University, Rome, Italy.
Tao
Hong
H
Grillo
Antonino
A
Franceschi
Francesco
F
Elia
Chiara
C
Zocco
Maria Assunta
MA
Gasbarrini
Giovanni
G
Sepulveda
Antonia R
AR
Gasbarrini
Antonio
A
D000328:Adult; D001407:Bacillus / Q000502:physiology*; D052160:Benzothiazoles; D002468:Cell Physiological Phenomena; D003959:Diamines; D004941:Esophagitis / Q000378:metabolism*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism / Q000382:microbiology; D007421:Intestine, Small / Q000378:metabolism / Q000382:microbiology*; D008297:Male; D046228:Microarray Analysis; D009930:Organic Chemicals; D016133:Polymerase Chain Reaction / Q000379:methods; D019936:Probiotics / Q000494:pharmacology*; D011804:Quinolines
D052160:Benzothiazoles; D003959:Diamines; D009930:Organic Chemicals; D011804:Quinolines; C098022:SYBR Green I