Inflammatory Bowel Disease–Associated Changes in the Gut: Focus on Kazan Patients

Abstract

Background Several studies have highlighted the role of host–microbiome interactions in the pathogenesis of inflammatory bowel disease (IBD), resulting in an increasing amount of data mainly focusing on Western patients. Because of the increasing prevalence of IBD in newly industrialized countries such as those in Asia, the Middle East, and South America, there is mounting interest in elucidating the gut microbiota of these populations. We present a comprehensive analysis of several IBD-related biomarkers and gut microbiota profiles and functions of a unique population of patients with IBD and healthy patients from Kazan (Republic of Tatarstan, Russia). Methods Blood and fecal IBD biomarkers, serum cytokines, and fecal short-chain fatty acid (SCFA) content were profiled. Finally, fecal microbiota composition was analyzed by 16S and whole-genome shotgun sequencing. Results Fecal microbiota whole-genome sequencing confirmed the presence of classic IBD dysbiotic features at the phylum level, with increased abundance of Proteobacteria, Actinobacteria, and Fusobacteria and decreased abundance of Firmicutes, Bacteroidetes, and Verrucomicrobia. At the genus level, the abundance of both fermentative (SCFA-producing and hydrogen (H2)-releasing) and hydrogenotrophic (H2-consuming) microbes was affected in patients with IBD. This imbalance was confirmed by the decreased abundance of SCFA species in the feces of patients with IBD and the change in anaerobic index, which mirrors the redox status of the intestine. Conclusions Our analyses highlighted how IBD-related dysbiotic microbiota—which are generally mainly linked to SCFA imbalance—may affect other important metabolic pathways, such as H2 metabolism, that are critical for host physiology and disease development.

Short chain fatty acids and colon motility in a mouse model of irritable bowel syndrome

“…The fecal pellets were collected directly from mice at 45 day after birth and stored at − 80 °C prior to SCFA determination. SCFAs were quantified in feces samples (1 g) by gas–liquid chromatographic analysis (GLC; Agilent, USA) [ 35 ]. Commercial acetic, propionic and butyric acids were used as standards [ 35 ].…”

“…SCFAs were quantified in feces samples (1 g) by gas–liquid chromatographic analysis (GLC; Agilent, USA) [ 35 ]. Commercial acetic, propionic and butyric acids were used as standards [ 35 ]. The overall level of SCFAs is presented as the sum of all concentrations of acids and isoacids in µg/g.…”

The Influence of Probiotics on the Firmicutes/Bacteroidetes Ratio in the Treatment of Obesity and Inflammatory Bowel disease

“…Analogous to studies that showed little effect of the F/B ratio on obesity, a decreased F/B ratio was also not observed in all IBD cases. A fecal microbial analysis of IBD patients from Kazan revealed decreased abundancies of Bacteroidetes, Firmicutes, and Verrucomicrobia, while the abundancies of Proteobacteria, Actinobacteria, and Fusobacteria were increased [79]. In 48 UC patients, the Bacteroides bacterial copy number in fecal samples was less than 10% of that in healthy individuals, and the Clostridium subcluster XIVab (Firmicutes) was also significantly lower [80].…”

Effect of chewing betel nut on the gut microbiota of Hainanese

“…SCFAs can be used as energy sources and critical small molecules to regulate host gene expression and inflammation [ 22 ]. Moreover, an increase in the abundance of Actinobacteria has usually been associated with diseases, such as inflammatory bowel disease [ 23 ], mental disorders [ 24 , 25 ], type 2 diabetes [ 26 ], and epilepsy [ 27 ]. Cyanobacteria play a role in neurodegenerative diseases by producing a variety of toxic metabolites, such as β-methylamino-1-alanine, 2,4-aminobutyric acid, and N-2-aminoethylglycine [ 28 ].…”