title: High-amylose resistant starch increases hormones and improves structure and function of the gastrointestinal tract: a microarray study.
abstract: OBJECTIVE
  Type 2 resistant starch from high-amylose maize (HAM-RS2) is associated with increased fermentation, increased expression of proglucagon (gene for GLP-1) and peptide YY (PYY) genes in the large intestine, and improved health. To determine what other genes are up- or downregulated with feeding of HAM-RS2, a microarray was performed.
  
  
  METHODS
  Adult, male Sprague Dawley rats were fed one of the following three diets for a 4-week study period: cornstarch control (CC, 3.74 kcal/g), dietary energy density control (EC, 3.27 kcal/g), and 30% HAM-RS2 (RS, 3.27 kcal/g). Rat microarray with ∼27,000 genes and validation of 94 representative genes with multiple qPCR were used to determine gene expression in total RNA extracts of cecal cells from rats. The RS versus EC comparison tested effects of fermentation as energy density of the diet was controlled.
  
  
  RESULTS
  For the RS versus EC comparison, 86% of the genes were validated from the microarray and the expression indicates promotion of cell growth, proliferation, differentiation, and apoptosis. Gut hormones GLP-1 and PYY were increased.
  
  
  CONCLUSIONS
  Gene expression results predict improved structure and function of the GI tract. Production of gut hormones may promote healthy functions beyond the GI tract.
authors.affiliation: Louisiana State University Agricultural Center, Baton Rouge, LA, USA. mkeenan@agctr.lsu.edu
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Keenan
authors.forename: Roy J
authors.initials: RJ
authors.lastname: Martin
authors.forename: Anne M
authors.initials: AM
authors.lastname: Raggio
authors.forename: Kathleen L
authors.initials: KL
authors.lastname: McCutcheon
authors.forename: Ian L
authors.initials: IL
authors.lastname: Brown
authors.forename: Anne
authors.initials: A
authors.lastname: Birkett
authors.forename: Susan S
authors.initials: SS
authors.lastname: Newman
authors.forename: Jihad
authors.initials: J
authors.lastname: Skaf
authors.forename: Maren
authors.initials: M
authors.lastname: Hegsted
authors.forename: Richard T
authors.initials: RT
authors.lastname: Tulley
authors.forename: Eric
authors.initials: E
authors.lastname: Blair
authors.forename: June
authors.initials: J
authors.lastname: Zhou
mesh_terms: D000688:Amylose / Q000008:administration & dosage*; D000818:Animals; D041981:Gastrointestinal Tract / Q000502:physiology*; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D013213:Starch / Q000494:pharmacology*
chemical_list: D013213:Starch; D000688:Amylose