Association of Habitual Dietary Fiber Intake and Fecal Microbiome Gene Abundance with Gastrointestinal Symptoms in an Irritable Bowel Syndrome Cohort

peer-reviewedObjectives: Dietary fibre supplementation is recognised as important for functional gastrointestinal disorders (FGID). The exact role of the microbiome in this relationship remains unclear. We explored differences in dietary fibre intake, GI symptoms and the fecal microbiome in those with FGID

Boletín Oficial de la provincia de Oviedo: Número 198 - 1937 julio 29

Recently it was shown that the closest invertebrate relatives to vertebrates are the tunicates rather than the much more morphologically similar cephalochordates [1]; while tunicate adult morphologies are very diverse their embryonic morphology displays a typical chordate body plan much like that of cephalochordates. In support of this position of tunicates on the phylogenetic tree of life tunicates also possess putative primitive vertebrate innovations. True vertebrate innovations are a set of structures exclusive to vertebrates, the gain of which are thought to have contributed to the transition of the ancestral vertebrate from sessile filter feeding to active predation [2, 3]. The accompanying increase in the organismal complexity seen in the early vertebrate lineage is thought to have been driven by the large amount of raw genetic material generated by the whole genome duplications at the base of the vertebrate lineage [4, 5]. Whole genome duplications create a large amount of redundant genetic material; for the most part the redundant genes are lost, however those genes that are retained undergo structural and functional evolution [6]. Certain types of genes are more likely to be retained after whole genome duplications than others, among these are the highly conserved set of developmental regulators known as the developmental toolbox [7]. The Sox superfamily are members of the developmental toolbox, they are divided into several conserved subgroups (SoxB1, SoxB2, SoxC, SoxD, SoxE and SoxF), these are involved in almost every aspect of vertebrate development, including the development of vertebrate innovations [8]. We compared developmental Sox expression patterns in a tunicate (Ciona savignyi) and vertebrates and were able to show that, potentially, there are several conserved expression patterns of different Sox genes between C. savignyi and vertebrates. This includes conservation of SoxB1 in early neuroectoderm, SoxC in mesenchyme, SoxE in neural tissue and SoxF in endoderm. In adult C. savignyi gonadal tissue SoxE expression was shown to be expressed in the testis, which is also found in vertebrates, and all of the C. savignyi Sox genes examined were found to be maternally expressed in Ciona. This thesis sheds light on the expression patterns of the conserved C. savignyi Sox genes during C. savignyi development and in adult gonads. By comparing these expression patterns to the already well-studied expression of homologous Sox genes during vertebrate development we can infer that some of the expression patterns seen in during C. savignyi development have been potentially conserved from the last common ancestor of chordates. However more information about the expression patterns of Sox genes in other tunicate species is needed to substantiate our conjectures

Two Gold Kiwifruit Daily for Effective Treatment of Constipation in Adults—A Randomized Clinical Trial

Chronic constipation is highly prevalent worldwide and may be managed with two green or three gold kiwifruit daily. It is unknown whether a smaller standard serve of gold kiwifruit (two daily) is as effective in constipation management. The study aimed to improve chronic constipation with two gold kiwifruit and psyllium in lieu of a placebo daily over four weeks. Adult participants (18–65 years) with functional constipation (FC, n = 11), constipation-predominant irritable bowel syndrome (IBS-C, n = 13), and healthy controls (n = 32) were block-randomized to the treatment order: gold kiwifruit (2/day) or psyllium (fiber-matched, 7.5 g/day) for four weeks, followed by four weeks washout before crossover. Outcomes included alterations of Gastrointestinal Symptom Rating Scale (GSRS) domains and weekly complete spontaneous bowel movements (CSBM) as part of a larger study. Both interventions reduced GSRS constipation domain scores in all subjects compared to baseline values (p = 0.004). All participants reported significantly more weekly CSBM (p = 0.014). Two gold kiwifruit decreased straining (p = 0.021). Two gold kiwifruit daily are as effective as fiber-matched psyllium in treating constipation in adults and should be considered as a treatment option

Concentrations of Fecal Bile Acids in Participants with Functional Gut Disorders and Healthy Controls

Bile acids are metabolites involved in nutrient absorption and signaling with levels influenced by dietary intake, metabolic processes, and the gut microbiome. We aimed to quantify 23 bile acids in fecal samples to ascertain if concentrations differed between healthy participants and those with functional gut disorders. Fecal bile acids were measured using liquid chromatography-mass spectrometry (LC-MS) in the COMFORT (The Christchurch IBS cohort to investigate mechanisms for gut relief and improved transit) cohort of 250 participants with Rome IV IBS (IBS-constipation (C), IBS-diarrhea (D), IBS-mixed (M)), functional gut disorders (functional constipation (FC), functional diarrhea (FD)) and healthy controls (FC n = 35, FD n = 13, IBS-C n = 24, IBS-D n = 52, IBS-M n = 29, and control n = 97). Dietary information was recorded to ascertain three-day dietary intake before fecal samples were collected. Fecal bile acid concentrations, predominantly primary bile acids, were significantly different between all functional gut disorder participants and healthy controls (CDCA p = 0.011, CA p = 0.003) and between constipation (FC + IBS-C) and diarrhea (FD + IBS-D) groups (CDCA p = 0.001, CA p = 0.0002). Comparison of bile acids between all functional groups showed four metabolites were significantly different, although analysis of combined groups (FC + IBS-C vs. FD + IBS-D) showed that 10 metabolites were significantly different. The bile acid profiles of FD individuals were similar to those with IBS-D, and likewise, those with FC were similar to IBS-C. Individuals with a diarrhea phenotype (FD + IBS-D) had higher concentrations of bile acids compared to those with constipation (FC + IBS-C). Bile acid metabolites distinguish between individuals with functional gut disorders and healthy controls but are similar in constipation (or diarrhea) whether classified as IBS or not