Intestinal Barrier and Gut Microbiota in Patients with Overlapping Irritable Bowel Syndrome and Functional Dyspepsia.

BACKGROUND: Disturbances in the intestinal barrier and gut dysbiosis have been observed in patients with functional bowel diseases. AIMS: To investigate the correlation between biomarkers of intestinal barrier disorders at different layers and the severity of symptoms in patients with overlapping diarrhea-predominant irritable bowel syndrome and functional dyspepsia (IDFO), as well as with gut microbiota taxa. METHODS: This study included 45 patients with IDFO and 16 healthy controls. Endoscopy with biopsy of the duodenum and sigmoid colon (SC) was performed to count intraepithelial lymphocytes (IELs) and mucosal eosinophils (subepithelial layer), assess fatty acid binding protein (FABP; epithelial layer) level, and stain for mucin-2 (MUC-2; pre-epithelial layer). Composition of the gut microbiota was evaluated using 16S rRNA gene sequencing. RESULTS: Patients with IDFO exhibited an increase in biomarkers of intestinal barrier disorders at all layers studied. IEL count in the duodenum was correlated with the severity of bloating (r = 0.336; p = 0.024) and, in the SC, was correlated with tenesmus severity (r = 0.303; p = 0.042). FABP-1 level in the SC was correlated with the severity of diarrhea (r = 0.577; p = 0.001), and FABP-5 concentration in the SC was correlated with abdominal distension (r = 0.477; p = 0.010). MUC-2 concentration in the duodenum was correlated with the severity of heartburn (r = 0.572; p = 0.025) and burning sensation in the epigastrium (r = 0.518; p = 0.048). All biomarkers of intestinal barrier permeability were correlated with the abundance of some gut microbiota taxa. CONCLUSION: Patients with IDFO exhibited disrupted intestinal barrier function in all layers, which was associated with clinical symptom severity and changes in the gut microbiota.

Effect of Rebamipide on the Intestinal Barrier, Gut Microbiota Structure and Function, and Symptom Severity Associated with Irritable Bowel Syndrome and Functional Dyspepsia Overlap: A Randomized Controlled Trial.

Treatment of functional digestive disorders is not always effective. Therefore, a search for new application points for potential drugs is perspective. Our aim is to evaluate the effect of rebamipide on symptom severity, intestinal barrier status, and intestinal microbiota composition and function in patients with diarrheal variant of irritable bowel syndrome overlapping with functional dyspepsia (D-IBSoFD). Sixty patients were randomized to receive trimebutine (TRI group), trimebutine + rebamipide (T + R group), or rebamipide (REB group) for 2 months. At the beginning and end of the study, patients were assessed for general health (SF-36), severity of digestive symptoms (Gastrointestinal Symptom Rating and 7 × 7 scales), state of the intestinal barrier, and composition (16S rRNA gene sequencing) and function (short-chain fatty acid fecal content) of the gut microbiota. The severity of most digestive symptoms was reduced in the REB and T + R groups to levels similar to that observed in the TRI group. The duodenal and sigmoidal lymphocytic and sigmoidal eosinophilic infiltration was decreased only in the REB and T + R groups, not in the TRI group. Serum zonulin levels were significantly decreased only in the REB group. A decrease in intraepithelial lymphocytic infiltration in the duodenum correlated with a decrease in the severity of rumbling and flatulence, while a decrease in infiltration within the sigmoid colon correlated with improved stool consistency and decreased severity of the sensation of incomplete bowel emptying. In conclusion, rebamipide improves the intestinal barrier condition and symptoms in D-IBSoFD. The rebamipide effects are not inferior to those of trimebutine.

Mitochondrial ATP Synthase and Mild Uncoupling by Butyl Ester of Rhodamine 19, C4R1.

The homeostasis of the transmembrane potential of hydrogen ions in mitochondria is a prerequisite for the normal mitochondrial functioning. However, in different pathological conditions it is advisable to slightly reduce the membrane potential, while maintaining it at levels sufficient to produce ATP that will ensure the normal functioning of the cell. A number of chemical agents have been found to provide mild uncoupling; however, natural proteins residing in mitochondrial membrane can carry this mission, such as proteins from the UCP family, an adenine nucleotide translocator and a dicarboxylate carrier. In this study, we demonstrated that the butyl ester of rhodamine 19, C4R1, binds to the components of the mitochondrial ATP synthase complex due to electrostatic interaction and has a good uncoupling effect. The more hydrophobic derivative C12R1 binds poorly to mitochondria with less uncoupling activity. Mass spectrometry confirmed that C4R1 binds to the ß-subunit of mitochondrial ATP synthase and based on molecular docking, a C4R1 binding model was constructed suggesting the binding site on the interface between the α- and ß-subunits, close to the anionic amino acid residues of the ß-subunit. The association of the uncoupling effect with binding suggests that the ATP synthase complex can provide induced uncoupling.

Heterogeneous Nuclear Ribonucleoproteins Involved in the Functioning of Telomeres in Malignant Cells.

Heterogeneous nuclear ribonucleoproteins (hnRNPs) are structurally and functionally distinct proteins containing specific domains and motifs that enable the proteins to bind certain nucleotide sequences, particularly those found in human telomeres. In human malignant cells (HMCs), hnRNP-A1-the most studied hnRNP-is an abundant multifunctional protein that interacts with telomeric DNA and affects telomerase function. In addition, it is believed that other hnRNPs in HMCs may also be involved in the maintenance of telomere length. Accordingly, these proteins are considered possible participants in the processes associated with HMC immortalization. In our review, we discuss the results of studies on different hnRNPs that may be crucial to solving molecular oncological problems and relevant to further investigations of these proteins in HMCs.

Proteomics of mammalian mitochondria in health and malignancy: From protein identification to function.

The mitochondrial set of proteins is a dynamic system, crucial for multiple functions of this organelle. Differential expression of genes in various tissues, alternative splicing, post-translational modifications, turnover and spatial dynamics of proteins are the factors that influence mitochondrial proteomes increasing their versatility. A wide range of high-throughput proteomic approaches are extensively used for identification, quantification and functional assessment of human and other mammalian mitochondrial proteins. This article reviews the methods and approaches which can be utilized for achieving one or another specific goal in mitochondrial investigations, and the recent advances in application of proteomics to study the roles of mitochondria in tumorigenesis and cancer progression.

Cofilin-1 and Other ADF/Cofilin Superfamily Members in Human Malignant Cells.

Identification of actin-depolymerizing factor homology (ADF-H) domains in the structures of several related proteins led first to the formation of the ADF/cofilin family, which then expanded to the ADF/cofilin superfamily. This superfamily includes the well-studied cofilin-1 (Cfl-1) and about a dozen different human proteins that interact directly or indirectly with the actin cytoskeleton, provide its remodeling, and alter cell motility. According to some data, Cfl-1 is contained in various human malignant cells (HMCs) and is involved in the formation of malignant properties, including invasiveness, metastatic potential, and resistance to chemotherapeutic drugs. The presence of other ADF/cofilin superfamily proteins in HMCs and their involvement in the regulation of cell motility were discovered with the use of various OMICS technologies. In our review, we discuss the results of the study of Cfl-1 and other ADF/cofilin superfamily proteins, which may be of interest for solving different problems of molecular oncology, as well as for the prospects of further investigations of these proteins in HMCs.

Study of Splicing Factor, Proline- and Glutamine-rich by Proteomic Techniques in Human Malignant and Nonmalignant Cell Lines.

Splicing factor, proline- and glutamine-rich protein (SFPQ), was identified in eight human cultivated cell lines by proteomic approaches. The cell proteins have been separated by means of two-dimensional gel electrophoresis in two modifications and identified by matrix-assisted laser desorption ionization mass spectrometry with further tandem mass spectrometry. The analysis of proteins from three human sarcomas cell lines (RD, U-2 OS and SK-UT-1B), three human renal adenocarcinomas cell lines (A-498, 769-P and OKP-GS), and two prostate adenocarcinomas cell lines (DU-145 and PC-3) revealed several electrophoretic isoforms of SFPQ protein. Differences between theoretical and experimental molecular masses and isoelectric points of SFPQ protein have been observed. Detailed investigation of SFPQ peptides by tandem mass spectrometry has detected new phosphorylation state of threonine residue in 168 position of SFPQ isoform in rhabdomyosarcoma cell line. Furthermore, SFPQ has not been identified during proteomic study of several nonmalignant cell lines, including cultured human mesenchymal stromal cells and myoblasts. However, SFPQ has been found in all malignant cell lines in high quantity. In particular, its fractions are abundant in sarcomas cell lines as opposed to nonmalignant mesenchymal cells. It is assumed that high quantity of SFPQ in sarcomas cell lines may affect tumorigenesis.

Enzyme immunoassay and proteomic characterization of troponin I as a marker of mammalian muscle compounds in raw meat and some meat products.

The skeletal muscle protein troponin I (TnI) has been characterized as a potential thermally stable and species-specific biomarker of mammalian muscle tissues in raw meat and meat products. This study proposed a technique for the quantification of TnI comprising protein extraction and sandwich enzyme-linked immunosorbent assay (ELISA). The technique is characterized by a TnI detection limit of 4.8 ng/ml with quantifiable concentrations ranging from 8.7 to 52 ng/ml. The method was shown to be suitable for detection of TnI in mammalian (beef, pork, lamb, and horse) meat but not in poultry (chicken, turkey, and duck) meat. In particular, the TnI content in beef was 0.40 3 ± 0.058 mg/g of wet tissue. The TnI estimations obtained for the pork and beef samples using ELISA were comparable to the proteomic analysis results. Thus, the quantitative study of TnI can be a convenient way to assess the mammalian muscle tissue content of various meat products.

Double perovskite Sr(2)FeMoO(6) films prepared by electrophoretic deposition.

The present work reports on the new approach to create metal-supported Sr2FeMoO6 (SFMO)-based electrodes that have high potential to be applied in solid oxide fuel cells. The SFMO films were formed on stainless steel substrates by electrophoretic deposition (EPD) method. Ethyl alcohol with phosphate ester as a dispersant and isopropyl alcohol with I2-acetone mixture as a charge additive were considered as an effective medium for EPD of SFMO particles. The synthesis of SFMO powder as well as suspension preparation and deposition kinetics were systematically studied. The effect of applied voltage on the thickness and morphology of SFMO films was established. The microstructure of the deposits was examined by electron microscopy. The thickness, morphology and porosity of the SFMO layers can be fine-tuned by varying solvent, charging additives, deposition time, and applied voltage. According to X-ray photoelectron spectroscopy analysis, it was found that Fe(3+)-Mo(5+) and Fe(2+)-Mo(6+) pairs coexist, whereas the valent balance shifts toward an Fe(2+)-Mo(6+) configuration.