P085 Gut microbiota profile changes in patients with Ulcerative Colitis

Inčiūraitė, R.(1)*;Gedgaudas, R.(1);Lukosevicius, R.(1);Plingyte, K.(1);Muskieta, T.(1);Juzenas, S.(1);Kupcinskas, J.(1);Skieceviciene, J.(1);

(1)Lithuanian University of Health Sciences, Institute for Digestive Research, Kaunas, Lithuania;

Background

Ulcerative Colitis (UC) is a chronic, relapsing inflammatory disease of the lower gastrointestinal tract. The frequency of UC is increasing worldwide, however, existing methods for both diagnostics and treatment of this disease are not efficient enough. It is known that besides comprised immune response, environmental and genetic factors, gut microbiota play a major role in the onset and course of UC. Therefore, efforts are currently being made to find and develop new gut microbiome-based tools to improve the management of UC. The aim of this study was to identify changes in the gut microbiome during active and quiescent UC.

Methods

Study included 72 subjects, who were divided into three age- and sex-matched groups: control (n=25), active UC (n=27) and quiescent UC (n=20). Total DNA was extracted from faeces, which was further subjected to the next generation sequencing of 16S rRNA-coding gene V1-V2 hypervariable region on MiSeq (Illumina) platform. Further, bioinformatics and statistical analysis were performed.

Results

Bacterial α-diversity, as assessed by Richness, Shannon and Simpson diversity indexes, revealed that control patients had highest α-diversity compared to patients with active UC or quiescent UC (p<0.05), but there were no differences between UC disease states (p>0.05). Significant microbial community clusters (β-diversity), as assessed by the Bray-Curtis dissimilarity index, were identified between control subjects and patients with active or quiescent UC (p=0.02, p<0.01, respectively). However, no significant clusters were found between different disease states (p=0.22). In-between samples dissimilarity assessed by Bray-Curtis dissimilarity index showed that samples from control subjects had higher in-between sample similarity (mean 0.542 ± 0.117) than patients with active (mean 0.638 ± 0.161) and quiescent (0.6 ± 0.145) UC. In addition, 16, 13 and 27 core taxa were identified in active, quiescent UC and control group, respectively. Differential abundance of CuneatibacterFaecalibacterium and Prevotellamassilia genera was detected when comparing control vs UC (both active and quiescent), Paraprevotella and Cuneatibacter genera – control vs active UC, FaecalibacteriumPrevotellamassiliaMediterraneibacter and Cuneatibacter genera – control vs quiescent UC.

Conclusion

In conclusion, this study revealed both qualitative and quantitative gut microbiota changes in active and quiescent UC. 
Study was funded by the Research Council of Lithuania (Grant No. S-MIP-20-56).