title: Resistant starch from high amylose maize (HAM-RS2) reduces body fat and increases gut bacteria in ovariectomized (OVX) rats.
abstract: OBJECTIVE
  Obesity after menopause is a health concern for older females. Changes in the microbiota are likely to occur with this condition. Modifying the microbiota with a prebiotic is a plausible strategy for improving the health of menopausal females.
  
  
  METHODS
  Resistant starch type 2 from high-amylose maize (HAM-RS2) was used as a prebiotic in rats in a 2 × 2 factorial study with two levels of HAM-RS2 (0 or 29.7% of weight of diet) referred to as energy control (EC) and HAM-RS2 diets, respectively; and two levels of surgery, ovariectomized (OVX) and sham.
  
  
  RESULTS
  In a 6-week, postsurgery recovery period, OVX rats gained more body weight with consumption of a similar amount of food. Subsequently, consumption of HAM-RS2 versus EC diets resulted in reduced abdominal fat in both OVX and sham rats; but when normalized for disemboweled body weight (body weight minus GI tract), there was no effect of surgery, only reduction with HAM-RS2. Targeted bacterial populations were estimated that are known to ferment HAM-RS2 or metabolize the products of that initial fermentation. OVX and sham rats demonstrated increased bacterial levels with dietary HAM-RS2 for all bacteria. Additionally, culture techniques and qPCR provided similar results.
  
  
  CONCLUSIONS
  This study shows that, as expected, OVX increases adiposity. However, contrary to previous effects seen in obese mice, this did not prevent fermentation of HAM-RS2 and consequently, the fat gain associated with OVX was attenuated.
authors.affiliation: Department of Human Ecology, Louisiana State University Agricultural Center, Baton Rouge, Louisiana, USA. mkeenan@agcenter.lsu.edu
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Keenan
authors.forename: Marlene
authors.initials: M
authors.lastname: Janes
authors.forename: Julina
authors.initials: J
authors.lastname: Robert
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: Christine
authors.initials: C
authors.lastname: Pelkman
authors.forename: Richard
authors.initials: R
authors.lastname: Tulley
authors.forename: M'Famara
authors.initials: M
authors.lastname: Goita
authors.forename: Holiday A
authors.initials: HA
authors.lastname: Durham
authors.forename: June
authors.initials: J
authors.lastname: Zhou
authors.forename: Reshani N
authors.initials: RN
authors.lastname: Senevirathne
mesh_terms: D000273:Adipose Tissue / Q000187:drug effects* / Q000378:metabolism; D000818:Animals; D001419:Bacteria / Q000187:drug effects*; D004032:Diet; D004043:Dietary Fiber / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D005285:Fermentation; D041981:Gastrointestinal Tract / Q000382:microbiology*; D008593:Menopause; D064307:Microbiota; D009765:Obesity / Q000209:etiology / Q000382:microbiology / Q000517:prevention & control*; D010052:Ovariectomy; D028321:Plant Preparations / Q000494:pharmacology / Q000627:therapeutic use; D056692:Prebiotics; D017207:Rats, Sprague-Dawley; D000084922:Resistant Starch; D013213:Starch / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D015430:Weight Gain / Q000187:drug effects; D003313:Zea mays / Q000737:chemistry*
chemical_list: D004043:Dietary Fiber; D028321:Plant Preparations; D056692:Prebiotics; D000084922:Resistant Starch; C572111:high-amylose maize type 2 resistant starch, maize; D013213:Starch