Profiling of the fecal microbiota and circulating microRNA-16 in IBS subjects with Blastocystis infection : a case–control study

Abstract

Irritable bowel syndrome (IBS) is a prevalent gastrointestinal (GI) tract disorder. Although the main reason for IBS is not clear, the interaction between intestinal microorganisms and the gut barrier seems to play an important role in pathogenesis of IBS. The current study aimed to investigate the effect of Blastocystis on the gut microbiota profile and the circulation levels of microRNA (mir)-16 of IBS patients compared to healthy subjects. Stool and blood samples were collected from 80 participants including 40 samples from each IBS and healthy group. Upon DNA extraction from stool samples, barcoding region and quantitative real-time PCR were analyzed to investigate Blastocystis and the microbiota profile, respectively. RNA was extracted from serum samples of included subjects and the expression of mir-16 was evaluated using stem-loop protocol and qreal-time PCR. Significant changes between IBS patients and healthy controls was observed in Firmicutes, Actinobacteria, Faecalibacterium, and Alistipes. In IBS patients, the relative abundance of Bifidobacteria was directly correlated with the presence of Blastocystis, while Alistipes was decreased with Blastocystis. Lactobacillus was significantly increased in Blastocystis carriers. In healthy subjects, the relative abundance of Bifidobacteria was decreased, but Alistipes was increased in Blastocystis carriers. The changes in the Firmicutes/Bacteroidetes ratio was not significant in different groups. The relative expression of mir-16 in Blastocystis-negative IBS patients and healthy carriers was significantly overexpressed compared to control group. The presence of Blastocystis, decreased the relative expression of mir-16 in IBS patients compared to Blastocystis-negative IBS patients. The present study revealed that Blastocystis has the ability to change the abundance of some phyla/genera of bacteria in IBS and healthy subjects. Moreover, Blastocystis seems to modulate the relative expression of microRNAs to control the gut atmosphere, apply its pathogenicity, and provide a favor niche for its colonization.

Global research states and trends of micro RNA in irritable bowel syndrome: a bibliometric analysis

“…Notably, these miRNAs and others, such as miR-18a*, miR-4802, miR-515-5p, and miR-1226-5p, shape the composition of gut microbiota, ultimately affecting the pathophysiology of intestinal disorders in the host [ 91 ]. Olyaiee et al [ 92 ] tested the serum and feces of patients with IBS and found that miR-16 was downregulated, and the relative abundance of Thickettsia , Actinobacteria , and Enterococcus faecalis increased. Mansour et al [ 93 ] found that the number of coliform bacteria increased in patients with IBS, while miR-199b expression decreased, particularly in patients with IBS-D, and intestinal flora negatively correlated with miR-199b.…”