Faecal and mucosal microbiota in patients with functional gastrointestinal disorders: Correlation with toll-like receptor 2/toll-like receptor 4 expression

Abstract

AIMTo investigate the intestinal luminal microbiota (LM) and mucosa-associated microbiota (MAM) in Chinese patients with functional gastrointestinal disorders (FGIDs) and examine the association between these communities and the expression of toll-like receptor (TLR) 2 and TLR4.METHODSThirty-two Chinese subjects who suffered from symptoms of FGIDs, as confirmed by gastroenterologists, were enrolled in this study. Fresh faecal samples and descending colonic mucosal biopsies were collected from the subjects before (faecal) and during (mucosal) flexible colonoscopy. For analysis of the samples, we performed high-throughput sequencing of the V3-V4 region of the 16S rRNA gene and reverse transcription (RT)-PCR to detect the expression of colonic TLR2 and TLR4. Differences in the stool and mucosal microbiota were examined and a correlation network analysis was performed.RESULTSThe microbiota of faecal samples was significantly more diverse and richer than that of the mucosal samples, and the LM and MAM populations differed significantly. TLR2 expression showed a significant positive correlation with TLR4 expression. In the MAM samples, the genera Faecalibacterium and Ruminococcus, which belong to the family Ruminococcaceae, were inversely correlated with TLR4 expression (r = -0.45817, P = 0.0083 and r = -0.5306, P = 0.0018, respectively). Granulicatella, which belongs to Carnobacteriaceae, and Streptococcus, which belongs to Streptococcaceae, were inversely correlated with TLR2 expression (r = -0.5573, P = 0.0010 and r = -0.5435, P = 0.0013, respectively). In the LM samples, examination at phylum, class, or order level revealed no correlation with TLR4 expression. Faecalibacterium, which belongs to Ruminococcaceae, and Streptococcus, which belongs to Streptococcaceae, were inversely correlated with TLR2 expression (r = -0.5743, P = 0.0058 and r = -0.3905, P = 0.0271, respectively).CONCLUSIONMicrobial compositions of LM and MAM in Chinese patients with FGIDs are different. Expression of TLRs may be affected by the type of bacteria that are present in the gut.

Comparison of microbial signatures between paired faecal and rectal biopsy samples from healthy volunteers using next-generation sequencing and culturomics

“…However, significant concordance was noted at both the phylum and genus levels between the bacterial profile of FHg samples and the paired BW sample from the same individual. This is contrary to previous observations in healthy volunteers and patients, where the bacterial populations from faeces and colonic biopsies were deemed to be distinct and nonrepresentative of each other [8,66,67]. It is worth noting that in these other studies, biopsy samples were taken after bowel preparation which reduces microbial content and therefore affects the microbial profile as previously mentioned.…”

Microbial Community Analysis of Saliva and Biopsies in Patients With Oral Lichen Planus

“…Janardhanam et al (2012) found that TLR2 messenger RNA (mRNA) was significantly lower in OLP epithelial cells and decreased in UWS epithelial cells of OLP patients. In fecal samples from patients with functional gastroenteropathy, Carnobacteriaceae was inversely correlated with the expression of TLR2 (Dong et al, 2017) and correlated with the immune status of leukemia patients (Wang et al, 2014). Besides, Veillonellaceae has been found to be associated with juvenile idiopathic arthritis involving autoimmune diseases, and increased in patients with non-enthesitisrelated arthritis (Di Paola et al, 2016) and schistosomiasis (Ajibola et al, 2019) associated with downregulation of TH2 immune response.…”

Change in the intestinal bacterial community structure associated with environmental microorganisms during the growth of Eriocheir sinensis

“…The more interesting phenomenon is that these four bacterial colonies belong to four dominant bacteria phyla. For the only species identified as Family, the Defluviitaleaceae, which belongs to the Firmicutes, has not been found in the intestinal tract of aquatic organisms and was found in the human gastrointestinal tract disease (Dong, Wang, Liu, & Yang, ). In this study, the population abundance of Defluviitaleaceae in young crabs was higher than that in juvenile and adult crabs, while the growth curve of these bacteria in the young population showed an exponential increase.…”