P794 Alterations of intestinal microbiota in ulcerative colitis
Danilova N.1, Abdulkhakov S.1,2, Grigoryeva T.*2, Dubinkina V.3, Odintsova V.4, Tyakht A.3,4, Pavlenko A.4, Odintsova A.2, Abdulkhakov R.1, Govorun V.4
1Kazan State Medical University, Kazan, Russian Federation 2Kazan Federal University, Kazan, Russian Federation 3Moscow Institute of Physics and Technology, Moscow, Russian Federation 4Federal Research Centre of Physical-Chemical Medicine, Moscow, Russian Federation
Changes in the composition of the intestinal microbiota are assumed to be associated with the onset and development of inflammatory bowel diseases (IBD).
The aim of our study was to identify the taxonomic features of the intestinal microbiota in patients with ulcerative colitis (UC).
The study included 46 patients with UC (25 men and 21 women, mean age 41.7 years). The disease duration ranged from 1 year to 36 years. All patients received 5-ASA as basic therapy. Whole genome sequencing was carried out on the SOLiD 5500 W platform (Life Technologies, Foster City, CA, USA). MetaPhlAn2 was used for taxonomic profiling of analyzed metagenomes. Previousy published metagenomes from 88 healthy subjects were used in the comparisonas control group.
The proportion of reads on the human genome was strongly increased: (14.61±18.62)% vs (0.47±0.91)% in the control group, indicating the presence of inflammatory processes in the gut of the patients. The most predominant were Bacteroides, Prevotella and Faecalibacterium genera. Escherichia, Lactobacillus, Bifidobacterium and Streptococcus genera were predominant in some of the examined samples.
A significant decrease of commensal taxa of the following families: Lachnospiraceae, Rikenellaceae, Acidaminococ, Enterococcaceae, Desulfovibrionaceae, Verrucomicrobiaceae, Methanobacteriaceae was revealed, with the exception of Enterobacteriacea, for which value was increased. Alpha-diversity index known to be associated with a healthy clinical status was used for assessment of the composition of microbiota. However, no significant difference was observed: for the control group it amounted to 3.32±0.56, for the experimental group it was 3.07±0.65.
The results of the analysis of metagenomic data from patients with UC, including assessment of the quality of the sequencing data, the assessment of taxonomic and functional composition of the microbiota showed significant changes compared to the samples of control group. The dysbiosis is characterized by the general decline of many commensal taxa. The lack of significantly increased taxa suggests the multi-directionality of the dysbiosis in UC patients.
This work was performed with financial support of the Ministry of Education and Science of the Russian Federation (Agreement No. RFMEFI57514X0075).