Obese ZDF rats fermented resistant starch with effects on gut microbiota but no reduction in abdominal fat

Mol Nutr Food Res. 2017 Jan;61(1):10.1002/mnfr.201501025. doi: 10.1002/mnfr.201501025. Epub 2016 Aug 11.


Scope: To determine if whole-grain (WG) flour with resistant starch (RS) will produce greater fermentation than isolated RS in obese Zucker Diabetic Fatty (ZDF) rats, and whether greater fermentation results in different microbiota, reduced abdominal fat, and increased insulin sensitivity.

Methods and results: This study utilized four groups fed diets made with either isolated digestible control starch, WG control flour (6.9% RS), isolated RS-rich corn starch (25% RS), or WG corn flour (25% RS). ZDF rats fermented RS and RS-rich WG flour to greatest extent among groups. High-RS groups had increased serum glucagon-like peptide 1 (GLP-1) active. Feeding isolated RS showed greater Bacteroidetes to Firmicutes phyla among groups, and rats consuming low RS diets possessed more bacteria in Lactobacillus genus. However, no differences in abdominal fat were observed, but rats with isolated RS had greatest insulin sensitivity among groups.

Conclusions: Data demonstrated ZDF rats (i) possess a microbiota that fermented RS, and (ii) WG high-RS fermented better than purified RS. However, fermentation and microbiota changes did not translate into reduced abdominal fat. The defective leptin receptor may limit ZDF rats from responding to increased GLP-1 and different microbiota for reducing abdominal fat, but did not prevent improved insulin sensitivity.

Keywords: Fermentation; Leptin signaling; Microbiota; Obese ZDF rats; Resistant starch; Whole-grain.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Abdominal Fat
  • Animals
  • Body Weight
  • Cecum / metabolism
  • Digestion
  • Fermentation
  • Gastrointestinal Microbiome* / genetics
  • Glucagon-Like Peptide 1 / metabolism
  • Insulin / metabolism
  • Male
  • Obesity / metabolism
  • Obesity / microbiology
  • Rats, Zucker
  • Receptors, Leptin / metabolism
  • Starch / metabolism*
  • Whole Grains*


  • Insulin
  • Receptors, Leptin
  • Glucagon-Like Peptide 1
  • Starch