Streptozotocin-induced type-1-diabetes disease onset in Sprague-Dawley rats is associated with an altered intestinal microbiota composition and decreased diversity

Microbiology (Reading). 2015 Jan;161(Pt 1):182-193. doi: 10.1099/mic.0.082610-0. Epub 2014 Nov 4.


There is a growing appreciation that microbiota composition can significantly affect host health and play a role in disease onset and progression. This study assessed the impact of streptozotocin (STZ)-induced type-1-diabetes (T1D) on intestinal microbiota composition and diversity in Sprague-Dawley rats, compared with healthy controls over time. T1D was induced by injection of a single dose (60 mg STZ kg(-1)) of STZ, administered via the intraperitoneal cavity. Total DNA was isolated from faecal pellets at weeks 0 (pre-STZ injection), 1, 2 and 4 and from caecal content at week 5 from both healthy and T1D groups. High-throughput 16S rRNA sequencing was employed to investigate intestinal microbiota composition. The data revealed that although intestinal microbiota composition between the groups was similar at week 0, a dramatic impact of T1D development on the microbiota was apparent post-STZ injection and for up to 5 weeks. Most notably, T1D onset was associated with a shift in the Bacteroidetes : Firmicutes ratio (P<0.05), while at the genus level, increased proportions of lactic acid producing bacteria such as Lactobacillus and Bifidobacterium were associated with the later stages of T1D progression (P<0.05). Coincidently, T1D increased caecal lactate levels (P<0.05). Microbial diversity was also reduced following T1D (P<0.05). Principle co-ordinate analyses demonstrated temporal clustering in T1D and control groups with distinct separation between groups. The results provide a comprehensive account of how T1D is associated with an altered intestinal microbiota composition and reduced microbial diversity over time.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibiotics, Antineoplastic / administration & dosage
  • Antibiotics, Antineoplastic / adverse effects
  • Biodiversity*
  • Diabetes Mellitus, Experimental / etiology*
  • Diabetes Mellitus, Type 1 / etiology*
  • Disease Models, Animal
  • Disease Progression
  • Fatty Acids, Volatile / metabolism
  • Intestines / microbiology*
  • Lactic Acid / biosynthesis
  • Male
  • Metagenome
  • Microbiota*
  • Rats
  • Rats, Sprague-Dawley
  • Streptozocin / administration & dosage
  • Streptozocin / adverse effects


  • Antibiotics, Antineoplastic
  • Fatty Acids, Volatile
  • Lactic Acid
  • Streptozocin