Faecal microbiota and fatty acids in feline chronic enteropathy.

BACKGROUND: Feline chronic enteropathy is a set of disorders defined as the presence of clinical signs of gastrointestinal disease for at least three weeks. The most common final diagnoses are inflammatory bowel disease and alimentary small cell lymphoma. The etiopathogenesis of these diseases is incompletely understood; however, it is hypothesised that they involve a combination of factors, including altered composition and/or functionality of the intestinal microbiome. An important factor in the interplay of the microbiome and host is the production of short- and branched-chain fatty acids.  The aim of this study was to evaluate the possible differences in faecal microbiota diversity, composition and fatty acid production between cats suffering from chronic enteropathy and healthy cats. Sixteen cats suffering from chronic enteropathy and fourteen healthy control cats were enrolled in the study. The microbiota compositions of faecal samples were analysed by using next-generation amplicon sequencing of the V3V4 fragment of the 16S rRNA gene. Fatty acids were evaluated by high-performance liquid chromatography. RESULTS: Both the alpha and beta diversities were significantly lower in samples obtained from cats with chronic enteropathy. The relative abundance of the phylum Proteobacteria, orders Lactobacillales and Enterobacterales, family Enteriobacteriaceae and genus Escherichia Shigella were higher in diseased cats, whereas the abundance of the phylum Bacteroidota and order Peptococcales were higher in control cats. The faecal concentrations of short-chain fatty acids were higher in cats with chronic enteropathy, with lower propionate proportions and higher butyrate proportions. CONCLUSION: The study revealed alterations in microbiota compositions and short-chain fatty acid concentration in cats suffering from chronic enteropathy, which is an important finding both for research on the pathogenesis of the disease and for potential therapeutic interventions in the form of faecal microbiota transplantation and/or probiotic supplementation.

Homeostasis of the Intestinal Mucosa in Healthy Horses-Correlation between the Fecal Microbiome, Secretory Immunoglobulin A and Fecal Egg Count.

The defensive function of the intestinal mucosa depends both on the ability to secrete immunoglobulin A and communication with the mucus microbiome. In horses, the functioning of this system is also influenced by the presence of nematode eggs. Feces collected from healthy horses were examined to determine the fecal egg count, immunoglobulin A level (ELISA), microbiome composition (Next-Generation Sequencing, NGS, V3−V4 and V7−V9 hypervariable regions of the 16S rRNA gene analysis and short-chain fatty acid (SCFA) production ((high-performance liquid chromatography, HPLC). In the taxonomic analysis within the phylum, the following order of dominance was found: Firmicutes, Bacteroidota, Verrucomicrobiota and Fibrobacterota. The coefficient of phylogenetic diversity of the microbiome positively correlated with both secretory immunoglobulin A (SIgA) [µg/g of feces] (p = 0.0354, r = 0.61) and SIgA [µg/mg of fecal protein] (p = 0.0382, r = 0.6) and with the number of Cyathostomum eggs (p = 0.0023, r = 0.79). Important components of the key microbiome in horses, such as phylum Proteobacteria and species Ruminococcus flavefaciens, were positively correlated with the fecal SIgA (p < 0.05). All the obtained results indicate the existence of significant relationships between the host response (SIgA production) and composition and SCFA production in the microbiome as well as the presence of small strongyles in the digestive tract of horses.

Are Matrix Metalloproteinase-9 and Tissue Inhibitor of Metalloproteinase-1 Useful as Markers in Diagnostic Management of Children with Newly Diagnosed Ulcerative Colitis?

Matrix Metaloproteinase-9 (MMP-9) and Tissue Inhibitor of Metaloproteinase-1 (TIMP-1), enzymes involved in tissue remodelling, have been previously reported to be overexpressed in the colonic mucosa of patients with Ulcerative colitis (UC). The aim of this study was to determine the relation of MMP-9 and TIMP-1 with UC phenotypes, the disease activity index and routinely tested inflammatory markers in newly diagnosed paediatric patients. The study group comprised 35 children diagnosed with UC and 20 control groups. Serum and faecal concentrations of MMP-9 and TIMP-1 were estimated using enzyme-like immunosorbent assay kits and correlated to the disease activity index (Paediatric Ulcerative Colitis Activity Index, PUCAI), UC phenotype (Paris Classification), inflammatory markers and endoscopic score (Mayo score). Children with UC presented with significantly higher serum and faecal concentrations of studied markers compared to the control group. Both serums, MMP-9 and TIMP-1, were higher in children with more extended and severe lesions in the colon. Furthermore, serum MMP-9 correlated with the Mayo score, Paris classification and C-reactive protein (CRP) levels. Serum TIMP-1 showed correlation with PUCAI, Paris Classification, CRP levels and the erythrocyte sedimentation rate. Serum and faecal levels of MMP-9 and TIMP-1 are useful in discriminating UC patients and non-invasive assessments of disease phenotypes. It seemed that simultaneous measurement of these proteins in combination with other common markers of inflammation could be applied in clinical practice.

Liver Pathology in Children with Diagnosed Inflammatory Bowel Disease-A Single Center Experience.

BACKGROUND: Inflammatory bowel disease (IBD) in children is frequently associated with liver pathology manifested as transient elevation of liver enzymes or specified liver diseases. The aim of the study was to evaluate the prevalence and the type of liver pathology in children with IBD within 2 years' follow-up after the IBD diagnosis. METHODS: We retrospectively reviewed records of children with IBD. Liver pathology was defined as elevated activity of liver enzymes (alanine transaminase (ALT) and/or gamma-glutamyl transpeptidase (GGT)) and bilirubin concentration in serum and/or as pathological changes of the organ on imaging tests (abdominal ultrasound and/or magnetic resonance cholangiopancreatography) or on liver histology performed when indicated. RESULTS: Liver pathology was detected in 21 from 119 children (18%), including 7 (17%) with Crohn's disease (CD) and 14 (18%) with ulcerative colitis (UC). Specified diagnosis for liver abnormality was found in 14 of 21 children (67%), including primary sclerosing cholangitis (PSC, 19%), non-alcoholic fatty liver disease (NAFLD, 19%), autoimmune sclerosing cholangitis (ASC, 5%), autoimmune hepatitis (AIH, 5%), cholelithiasis (5%), drug-induced liver disease (9%) and viral infection (herpes simplex virus, 5%). Most patients manifested mild IBD or were in clinical remission at the time of liver pathology diagnosis. 14% of patients with liver disease (including only cases with PSC) were diagnosed before IBD, 33% at the same time, and 52% in the later period. Patients with the specified diagnosis of liver pathology were younger, had higher ALT activity and more often demonstrated liver abnormalities on imaging tests. UC patients with idiopathic elevation of liver enzymes had higher pediatric ulcerative colitis activity index scores compared to children with specified liver disease. CONCLUSIONS: Liver pathology was observed in a significant percentage of children with IBD in our study. The majority of cases of hepatobiliary abnormalities were detected after diagnosis of IBD; therefore, children with IBD should undergo routine monitoring of liver enzymes.

Cyclic OmpC peptidic epitope conjugated to tetanus toxoid as a potential vaccine candidate against shigellosis.

In earlier works we have described that mice immunized with outer membrane protein OmpC survive the challenge with live Shigella flexnerii 3a. We have also identified conformational epitope of this protein, that was recognized by mice antibodies. The aim of current work was to investigate whether synthetic OmpC epitope homologs can elicit immunological response sufficient in protecting mice against shigellosis. Several linear peptides containing RYDERY motif were synthesized and conjugated to poly-lysine. These conjugates appeared to be poor immunogens and to boost the immunological response an addition of the adjuvant (MPL) was required. Unfortunately, the MPL alone caused a very high immunological reaction that was masking response to peptidic epitope. Under those circumstances we used tetanus toxoid (TT) as the carrier protein for the peptides and the agent stimulating immunological response. Series of cyclic peptides, homologs of the OmpC main epitope were synthesized and conjugated to TT. The loop size in cyclic peptides varied by number of glycine residues, i.e., 1-3 residues added to the GLNRYDERYIGK motif. The linear GLNRYDERYIGC-TT was also prepared as the control. The latter conjugate gave the highest immunological response, followed by the cyclic-GGLNRYDERYIGC-TT and cyclic-GLNRYDERYIGC-TT. The third peptide, cyclic-GGGLNRYDERYIGC-TT, gave a very low response, although it was the most resistant to proteolysis. However, antibodies obtained against cyclic-GGLNRYDERYIGC-TT were more potent to recognize both OmpC and Shigella flexnerii 3a cells than the antibodies against linear GLNRYDERYIGC-TT. Furthermore, the monoclonal antibodies raised against linear GLNRYDERYIGC-TT showed 20-fold lower dissociation constant (KD) than the naturally occurring polyclonal antibodies from umbilical cord sera. Monoclonal antibodies also gave a weaker signal in electron microscope than mice and human polyclonal antibodies. In overall, our results point to cyclic peptides as better candidates for a vaccine development, since they are eliciting production of the higher affinity antibodies against Shigella cells and OmpC.

The profile of polyunsaturated fatty acids in juvenile idiopathic arthritis and association with disease activity.

We investigated the association between dietary intake of n-3 and n-6 polyunsaturated fatty acids (PUFAs), serum profiles, and immune and inflammatory markers in juvenile idiopathic arthritis (JIA) in relation to onset, activity, and duration. A total of 66 JIA patients and 42 controls were included. Serum PUFA levels were assessed by gas-liquid chromatography-mass spectrometry, a dietary intake by 7-day dietary record method, and IL-6, IL-10, and IL-17A levels using ELISA. Dietary PUFA intake did not differ between the JIA group and controls. Intakes of n-6 and n-3 PUFA and serum levels were not associated. Levels of total n-6 PUFA and linoleic acid (LA) were higher in inactive JIA than in active JIA. Patients with active and short-lasting disease (less than 3 months from diagnosis) had significantly lower levels of arachidonic acid (AA) and docosahexaenoic acid (DHA) than the control. Serum α-linolenic acid (ALA) levels were significantly higher in poly-JIA than in oligo-JIA and in controls. We found significantly higher serum IL-10 levels in JIA than in controls. Serum n-6 and n-3 levels were significantly negatively correlated with active joint count, erythrocyte sedimentation rate, and C-reactive protein and positively with platelet count. Our study presents the low levels of AA and DHA in the active phase of short-lasting JIA, particularly poly-JIA, and the relationship between n-6 and n-3 PUFA and classic markers of inflammation. PUFAs may contribute to the pathogenesis of JIA and support a necessity to identify new targets suitable for successful interventional studies in JIA patients.