Low Vitamin K and Vitamin D Dietary Intake in Patients with Inflammatory Bowel Diseases

The inadequate dietary intake of Vitamin D and Vitamin K is an easily reversible factor favoring IBD-associated bone loss, but data on Vitamin K are lacking. A 28-item quantitative food frequency questionnaire was administered to 193 IBD patients (89 Crohn’s disease and 104 ulcerative colitis), and 199 controls. Patients’ demographics, clinical and laboratory findings were analyzed in relation to recommended daily allowances. VitD intake was inadequate both in the IBD and control patients (8.3 ± 4.5 µg/day in IBD, 53.1% RDA, and 9.7 ± 5.9 µg/day, 63.2% RDA, respectively). Conversely, the mean ViK intake was less than adequate in IBD, at 116.7 ± 116.3 µg/day (78.7% RDA), and high in controls, at 203.1 ± 166.9 µg/day (138.8% RDA). Nonetheless, due to marked interindividual differences, diets were severely lacking VitK in 40% of UC and 49% of CD patients, more so in females and those with active disease. The intake of Vit D was non-significantly lower in colitis than that in Crohn’s disease (7.9 vs. 8.7 µg/day). The opposite was observed for VitK (123.5 vs. 107.0 µg/day). Thus, the diet lacks the micronutrients involved in bone wellbeing in a large proportion of IBD patients. While VitD supplementation is the rule, VitK shortages need proactive nutritional intervention. Keywords: IBD; vitamin K; vitamin D; diet in IB

Inactivation of nuclear GSK3 beta by Ser(389) phosphorylation promotes lymphocyte fitness during DNA double-strand break response

Variable, diversity and joining (V(D)J) recombination and immunoglobulin class switch recombination (CSR) are key processes in adaptive immune responses that naturally generate DNA double-strand breaks (DSBs) and trigger a DNA repair response. It is unclear whether this response is associated with distinct survival signals that protect T and B cells. Glycogen synthase kinase 3 beta (GSK3 beta) is a constitutively active kinase known to promote cell death. Here we show that phosphorylation of GSK3 beta on Ser(389) by p38 MAPK (mitogen-activated protein kinase) is induced selectively by DSBs through ATM (ataxia telangiectasia mutated) as a unique mechanism to attenuate the activity of nuclear GSK3 beta and promote survival of cells undergoing DSBs. Inability to inactivate GSK3 beta through Ser(389) phosphorylation in Ser(389)Ala knockin mice causes a decrease in the fitness of cells undergoing V(D)J recombination and CSR. Preselection-Tcrb repertoire is impaired and antigen-specific IgG antibody responses following immunization are blunted in Ser(389)GSK3 beta knockin mice. Thus, GSK3 beta emerges as an important modulator of the adaptive immune response.We thank Dr T. Honjo and Dr K. Otsu for the generation of the original AID deficient mice and the p38 flox/flox mice, respectively. We thank C. Charland for flow cytometry analysis and cell sorting, the Vermont Cancer Center DNA Sequencing Facility and the University of Vermont College of Med. Microscopy Imaging Center for their services. We thank Dr D.R. Green and Dr R.C. Budd for helpful discussion regarding the mechanisms of cell death and reagents. This work was supported by NIH grant R01 AI051454 (M.R. and T.M.T.), P20 GM103496 (T.M.T.) NIH grant R37 GM41052 (M.S.K.) and Lake Champlain Cancer Research Organization (M.R.).S

Long-term outcomes of acute severe ulcerative colitis in the rescue therapy era: A multicentre cohort study

BACKGROUND: The long‐term course of ulcerative colitis after a severe attack is poorly understood. Second‐line rescue therapy with cyclosporine or infliximab is effective for reducing short‐term colectomy but the impact in the long‐term is controversial. OBJECTIVE: The purpose of this study was to evaluate the long‐term course of acute severe ulcerative colitis patients who avoid early colectomy either because of response to steroids or rescue therapy. METHODS: This was a multicentre retrospective cohort study of adult patients with acute severe ulcerative colitis admitted to Italian inflammatory bowel disease referral centres from 2005 to 2017. All patients received intravenous steroids, and those who did not respond received either rescue therapy or colectomy. For patients who avoided early colectomy (within 3 months from the index attack), we recorded the date of colectomy, last follow‐up visit or death. The primary end‐point was long‐term colectomy rate in patients avoiding early colectomy. RESULTS: From the included 372 patients with acute severe ulcerative colitis, 337 (90.6%) avoided early colectomy. From those, 60.5% were responsive to steroids and 39.5% to the rescue therapy. Median follow‐up was 44 months (interquartile range, 21–85). Colectomy‐free survival probability was 93.5%, 81.5% and 79.4% at 1, 3 and 5 years, respectively. Colectomy risk was higher among rescue therapy users than in steroid‐responders (log‐rank test, p = 0.02). At multivariate analysis response to steroids was independently associated with a lower risk of long‐term colectomy (adjusted odds ratio = 0.5; 95% confidence interval, 0.2–0.8), while previous exposure to antitumour necrosis factor‐α agents was associated with an increased risk (adjusted odds ratio = 3.0; 95% confidence interval, 1.5–5.7). Approximately 50% of patients required additional therapy or new hospitalisation within 5 years due to a recurrent flare. Death occurred in three patients (0.9%). CONCLUSIONS: Patients with acute severe ulcerative colitis avoiding early colectomy are at risk of long‐term colectomy, especially if previously exposed to antitumour necrosis factor‐α agents or if rescue therapy during the acute attack was required because of steroid refractoriness

Lafora disease E3-ubiquitin ligase malin is related to TRIM32 at both the phylogenetic and functional level

<p>Abstract</p> <p>Background</p> <p>Malin is an E3-ubiquitin ligase that is mutated in Lafora disease, a fatal form of progressive myoclonus epilepsy. In order to perform its function, malin forms a functional complex with laforin, a glucan phosphatase that facilitates targeting of malin to its corresponding substrates. While laforin phylogeny has been studied, there are no data on the evolutionary lineage of malin.</p> <p>Results</p> <p>After an extensive search for malin orthologs, we found that malin is present in all vertebrate species and a cephalochordate, in contrast with the broader species distribution previously reported for laforin. These data suggest that in addition to forming a functional complex, laforin and perhaps malin may also have independent functions. In addition, we found that malin shares significant identity with the E3-ubiquitin ligase TRIM32, which belongs to the tripartite-motif containing family of proteins. We present experimental evidence that both malin and TRIM32 share some substrates for ubiquitination, although they produce ubiquitin chains with different topologies. However, TRIM32-specific substrates were not reciprocally ubiquitinated by the laforin-malin complex.</p> <p>Conclusions</p> <p>We found that malin and laforin are not conserved in the same genomes. In addition, we found that malin shares significant identity with the E3-ubiquitin ligase TRIM32. The latter result suggests a common origin for malin and TRIM32 and provides insights into possible functional relationships between both proteins.</p

A comparison of diagnostic tests for lactose malabsorption - which one is the best?

<p>Abstract</p> <p>Background</p> <p>Perceived milk intolerance is a common complaint, and tests for lactose malabsorption (LM) are unreliable. This study assesses the agreement between diagnostic tests for LM and describes the diagnostic properties of the tests.</p> <p>Methods</p> <p>Patients above 18 years of age with suspected LM were included. After oral intake of 25 g lactose, a combined test with measurement of serum glucose (s-glucose) and hydrogen (H2) and methane (CH4) in expired air was performed and symptoms were recorded. In patients with discrepancies between the results, the combined test was repeated and a gene test for lactose non-persistence was added. The diagnosis of LM was based on an evaluation of all tests. The following tests were compared: Increase in H2, CH4, H2+CH4 and H2+CH4x2 in expired air, increase in s-glucose, and symptoms. The agreement was calculated and the diagnostic properties described.</p> <p>Results</p> <p>Sixty patients were included, seven (12%) had LM. The agreement (kappa-values) between the methods varied from 0.25 to 0.91. The best test was the lactose breath test with measurement of the increase in H2 + CH4x2 in expired air. With a cut-off level < 18 ppm, the area under the ROC-curve was 0.967 and sensitivity was 100%. This shows that measurement of CH4 in addition to H2 improves the diagnostic properties of the breath test.</p> <p>Conclusion</p> <p>The agreement between commonly used methods for the diagnosis of LM was unsatisfactory. A lactose breath test with measurement of H2 + CH4x2 in expired air had the best diagnostic properties.</p

Dysregulated RNA polyadenylation contributes to metabolic impairment in non-alcoholic fatty liver disease

Pre-mRNA processing is an essential mechanism for the generation of mature mRNA and the regulation of gene expression in eukaryotic cells. While defects in pre-mRNA processing have been implicated in a number of diseases their involvement in metabolic pathologies is still unclear. Here, we show that both alternative splicing and alternative polyadenylation, two major steps in pre-mRNA processing, are significantly altered in non-alcoholic fatty liver disease (NAFLD). Moreover, we find that Serine and Arginine Rich Splicing Factor 10 (SRSF10) binding is enriched adjacent to consensus polyadenylation motifs and its expression is significantly decreased in NAFLD, suggesting a role mediating pre-mRNA dysregulation in this condition. Consistently, inactivation of SRSF10 in mouse and human hepatocytes in vitro, and in mouse liver in vivo, was found to dysregulate polyadenylation of key metabolic genes such as peroxisome proliferator-activated receptor alpha (PPARA) and exacerbate diet-induced metabolic dysfunction. Collectively our work implicates dysregulated pre-mRNA polyadenylation in obesity-induced liver disease and uncovers a novel role for SRSF10 in this process

Safety of treatments for inflammatory bowel disease: Clinical practice guidelines of the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD)

Inflammatory bowel diseases are chronic conditions of unknown etiology, showing a growing incidence and prevalence in several countries, including Italy. Although the etiology of Crohn's disease and ulcerative colitis is unknown, due to the current knowledge regarding their pathogenesis, effective treatment strategies have been developed. Several guidelines are available regarding the efficacy and safety of available drug treatments for inflammatory bowel diseases. Nevertheless, national guidelines provide additional information adapted to local feasibility, costs and legal issues related to the use of the same drugs. These observations prompted the Italian Group for the Study of Inflammatory Bowel Disease (IG-IBD) to establish Italian guidelines on the safety of currently available treatments for Crohn's disease and ulcerative colitis. These guidelines discuss the use of aminosalicylates, systemic and low bioavailability corticosteroids, antibiotics (metronidazole, ciprofloxacin, rifaximin), thiopurines, methotrexate, cyclosporine A, TNFα antagonists, vedolizumab, and combination therapies. These guidelines are based on current knowledge derived from evidence-based medicine coupled with clinical experience of a national working group

Laforin, a Dual Specificity Phosphatase Involved in Lafora Disease, Is Present Mainly as Monomeric Form with Full Phosphatase Activity

Lafora Disease (LD) is a fatal neurodegenerative epileptic disorder that presents as a neurological deterioration with the accumulation of insoluble, intracellular, hyperphosphorylated carbohydrates called Lafora bodies (LBs). LD is caused by mutations in either the gene encoding laforin or malin. Laforin contains a dual specificity phosphatase domain and a carbohydrate-binding module, and is a member of the recently described family of glucan phosphatases. In the current study, we investigated the functional and physiological relevance of laforin dimerization. We purified recombinant human laforin and subjected the monomer and dimer fractions to denaturing gel electrophoresis, mass spectrometry, phosphatase assays, protein-protein interaction assays, and glucan binding assays. Our results demonstrate that laforin prevalently exists as a monomer with a small dimer fraction both in vitro and in vivo. Of mechanistic importance, laforin monomer and dimer possess equal phosphatase activity, and they both associate with malin and bind glucans to a similar extent. However, we found differences between the two states' ability to interact simultaneously with malin and carbohydrates. Furthermore, we tested other members of the glucan phosphatase family. Cumulatively, our data suggest that laforin monomer is the dominant form of the protein and that it contains phosphatase activity