title: Bacillus clausii effect on gene expression pattern in small bowel mucosa using DNA microarray analysis.
abstract: 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.
authors.affiliation: Department of Gastroenterology, Catholic University, Rome, Italy.
authors.forename: Simona
authors.initials: S
authors.lastname: Di Caro
authors.forename: Hong
authors.initials: H
authors.lastname: Tao
authors.forename: Antonino
authors.initials: A
authors.lastname: Grillo
authors.forename: Francesco
authors.initials: F
authors.lastname: Franceschi
authors.forename: Chiara
authors.initials: C
authors.lastname: Elia
authors.forename: Maria Assunta
authors.initials: MA
authors.lastname: Zocco
authors.forename: Giovanni
authors.initials: G
authors.lastname: Gasbarrini
authors.forename: Antonia R
authors.initials: AR
authors.lastname: Sepulveda
authors.forename: Antonio
authors.initials: A
authors.lastname: Gasbarrini
mesh_terms: 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
chemical_list: D052160:Benzothiazoles; D003959:Diamines; D009930:Organic Chemicals; D011804:Quinolines; C098022:SYBR Green I