Efecto de la administración oral del agente estabilizador del mastocito, cromoglicato disódico, sobre la evolución clínica y biológica en pacientes con síndrome del intestino irritable con predominio de diarrea

El Síndrome del Intestino Irritable (SII) es un trastorno funcional con elevada prevalencia en la sociedad que se caracteriza por la presencia de dolor o molestia abdominal asociada a cambios en el hábito deposicional. Su diagnóstico es clínico al carecer de marcadores biológicos, sin embargo, las evidencias científicas aportadas en los últimos años sugieren una etiología multifactorial que origina, en la mucosa intestinal del SII con predominio de diarrea (SII-D), una condición de inflamación crónica de bajo grado y una alteración en la función de la barrera intestinal asociada a la hipersensibilidad visceral y la alteración motora en estos pacientes. El tejido linfoide asociado al intestino forma parte de la función barrera intestinal y es determinante en el mantenimiento de la homeostasis. El exceso de activación del sistema inmunológico se relaciona con alteraciones en las funciones intestinales y, en consecuencia, con el desarrollo de patologías intestinales. Concretamente, la activación del mastocito y su proximidad a terminaciones nerviosas en la mucosa se asocian a la sintomatología característica del SII, por lo que estrategias dirigidas a la modulación de su activación podrían ser beneficiosas para la recuperación de la homeostasis intestinal y la mejoría clínica de estos pacientes. Este trabajo analiza el efecto del tratamiento oral con cromoglicato disódico (CGDS), un agente estabilizador del mastocito, en la evolución de los síntomas propios del SII y los cambios moleculares asociados a la respuesta clínica que acontecen en la mucosa intestinal. Para ello, realizamos un primer estudio exploratorio durante 6 meses que comparó el efecto de la administración oral de CGDS oral (600mg/día) en pacientes de SII-D sobre las principales manifestaciones clínicas frente a otra cohorte que no recibió tratamiento alguno. El CGDS mostró un beneficio clínico al reducir en la mayoría de los pacientes la intensidad del dolor abdominal un 50% y normalizar la consistencia de las deposiciones en el 75%. Además de la eficacia clínica, la expresión de genes asociados a la activación del mastocito y la inmunidad innata en la mucosa yeyunal, disminuyó de forma significativa tras el tratamiento con CGDS, mostrando niveles similares a los presentes en los sujetos sanos. Para determinar la eficacia terapéutica del CGDS e identificar los mecanismos subyacentes a la mejoría clínica, realizamos un ensayo clínico durante 6 meses, randomizado, doble ciego y controlado con placebo en una cohorte de 42 pacientes de SII-D (razón de 1:1). Ambos grupos mostraron una disminución significativa en los valores de severidad del SII y dolor abdominal sin hallar diferencias entre ambos. Sin embargo, el efecto del CGDS fue mayor respecto al placebo en la mejoría de la consistencia de las deposiciones. Por otra parte, el grupo que recibió placebo, mostró una asociación entre la depresión y la intensidad del dolor abdominal, lo que sugiere la existencia de mecanismos subyacentes a la respuesta al placebo. El CGDS generó un impacto mayor sobre el transcriptoma de la mucosa intestinal en comparación al placebo, asociado a mecanismos de control del balance de la respuesta inmunológica, la homeostasis del epitelio y el estrés oxidativo. En resumen, hemos contribuido a ampliar el conocimiento actual sobre los efectos clínicos y biológicos derivados de la estabilización del mastocito de la mucosa intestinal. El CGDS mejora principalmente la diarrea y la consistencia de las deposiciones, entre los síntomas principales del SII-D. Este efecto se asocia al restablecimiento de la homeostasis intestinal por su acción antiinflamatoria y antioxidante.Irritable Bowel Syndrome (IBS) is a chronic functional bowel disorder characterized by abdominal pain or discomfort and altered bowel habit. Despite its high prevalence in western societies, there is no reliable biological marker and its diagnosis relies on symptom-based criteria. However, in diarrhea-prone IBS (IBS-D), a growing body of evidence suggests a multifactorial etiology including intestinal mucosal low-grade inflammation and intestinal barrier dysfunction. Importantly, these features are associated with visceral hypersensitivity and altered intestinal motility, accepted as features of IBS. The gut associated lymphoid tissue has a key role in maintaining the intestinal barrier and contributing to homeostasis. Over-activation of the intestinal immune system is linked to disturbances in the intestinal functions and to the development of intestinal disorders. Specifically, increased mucosal mast cell (MC) activation and their proximity to nerve endings are associated to IBS symptoms. Therefore, strategies addressed at modulating MC activation might have a clinical benefit in IBS-D patients. This work analyses the effect on clinical symptoms evolution after long-term administration of oral disodium cromoglycate (DSCG) and identifies the underlying molecular mechanisms associated to the clinical improvement. To confirm the hypothesis, we first carried out an exploratory study in which we evaluated the impact of oral administration of DSCG (600 mg/day) on specific symptoms in IBS-D and compared to a cohort of untreated IBS-D patients. DSCG-treated patients showed clinical benefit as the majority of patients reported at least a 50% of improvement on their abdominal pain and bowel movements, and over 75% normalized the consistency of stools. Besides the clinical improvement, our findings corroborate the effectiveness of oral DSCG to promote the stabilization of gut mucosal mast cells by down-regulation of tryptase, as well as innate immunity molecules to comparable levels in the healthy population. In order to confirm the clinical efficacy of DSCG and to address its underlying mechanisms, we carried out a 6-month randomized, double blind placebo-controlled clinical trial in a cohort of 42 IBS-D (ratio 1:1). Both groups reported a significant improvement in IBS severity score and pain intensity, although without significant differences between groups. However, the effect of CGDS was higher over placebo in the improvement of stool consistency. Moreover, the placebo group showed an association between depression and abdominal pain intensity, suggesting the existence of mechanisms underlying the placebo response. The DSCG produced a greater impact on the intestinal mucosal transcriptome as compared to placebo, and it was associated with balance control mechanisms of the immune response, epithelial homeostasis and oxidative stress. In summary, this study has contributed to the current knowledge of the clinical and biological effects resulting from mucosal mast cell stabilization. CGDS oral treatment improves diarrhea and stool consistency, among the main symptoms of IBS-D. This effect is associated with the restoration of intestinal homeostasis by its anti-inflammatory and antioxidant mechanisms of action

3D-nanostructured Au electrodes for the event-specific detection of MON810 transgenic maize

In the present work, the development of a genosensor for the event-specific detection of MON810 transgenic maize is proposed. Taking advantage of nanostructuration, a cost-effective three dimensional electrode was fabricated and a ternary monolayer containing a dithiol, a monothiol and the thiolated capture probe was optimized to minimize the unspecific signals. A sandwich format assay was selected as a way of precluding inefficient hybridization associated with stable secondary target structures. A comparison between the analytical performance of the Au nanostructured electrodes and commercially available screen-printed electrodes highlighted the superior performance of the nanostructured ones. Finally, the genosensor was effectively applied to detect the transgenic sequence in real samples, showing its potential for future quantitative analysis

Risk factors associated with the development of delirium in general ICU patients. A prospective observational study.

Objective We aimed to analyze risk factors related to the development of delirium, aiming for early intervention in patients with greater risk. Material and methods Observational study, including prospectively collected patients treated in a single general ICU. These were classified into two groups, according to whether they developed delirium or not (screening performed using CAM-ICU tool). Demographics and clinical data were analyzed. Multivariate logistic regression analyses were performed to quantify existing associations. Results 1462 patients were included. 93 developed delirium (incidence: 6.3%). These were older, scored higher on the Clinical Frailty Scale, on the risk scores on admission (SAPS-3 and SOFA), and had a greater number of organ failures (OF). We observed more incidence of delirium in patients who (a) presented more than two OF (20.4%; OR 4.9; CI95%: 2.9–8.2), and (b) were more than 74 years old albeit having <2 OF (8.6%; OR 2.1; CI95%: 1.3–3.5). Patients who developed delirium had longer ICU and hospital length-of-stays and a higher rate of readmission. Conclusions The highest risk observed for developing delirium clustered in patients who presented more than 2 OF and patients over 74 years old. The detection of patients at high risk for developing delirium could imply a change in management and improved quality of care.post-print382 K

DNA-based biosensor for the electrocatalytic determination of antioxidant capacity in beverages

Reactive oxygen species (ROS) are produced as a consequence of normal aerobic metabolism and are able to induce DNA oxidative damage. At the cellular level, the evaluation of the protective effect of antioxidants can be achieved by examining the integrity of the DNA nucleobases using electrochemical techniques. Herein, the use of an adenine-rich oligonucleotide (dA21) adsorbed on carbon paste electrodes for the assessment of the antioxidant capacity is proposed. The method was based on the partial damage of a DNA layer adsorbed on the electrode surface by OH• radicals generated by Fenton reaction and the subsequent electrochemical oxidation of the intact adenine bases to generate an oxidation product that was able to catalyze the oxidation of NADH. The presence of antioxidant compounds scavenged hydroxyl radicals leaving more adenines unoxidized, and thus, increasing the electrocatalytic current of NADHmeasured by differential pulse voltammetry (DPV). Using ascorbic acid (AA) as a model antioxidant species, the detection of as low as 50nMof AA in aqueous solution was possible. The protection efficiency was evaluated for several antioxidant compounds. The biosensor was applied to the determination of the total antioxidant capacity (TAC) in beverages

The Intestinal Gas Questionnaire (IGQ) : Psychometric validation of a new instrument for measuring gas-related symptoms and their impact on daily life among general population and irritable bowel syndrome

Gas-related symptoms (GRS) are common in the general population (GPop) and among patients with disorders of gut-brain interactions but there is no patient-reported outcome evaluating these symptoms and their impact on daily life. We have previously developed a 43-item intestinal gas questionnaire (IGQ). The aim of the present study is to perform a psychometric validation of this instrument. Participants (119 from the GPop and 186 irritable bowel syndrome (IBS) patients) were recruited from 3 countries (UK, Spain, France). IBS patients fulfilled ROME IV criteria with an IBS severity score between 150 and 300. Participants completed the IGQ, the functional Digestive Disorders Quality of Life (FDDQL), and the EQ-5D. A subgroup (n = 90) repeated the IGQ completion after 7 days on paper or electronically. From the original IGQ questionnaire, 26 items were deleted because of poor performance. Confirmatory factorial analysis on the remaining 17 items (7 symptom and 10 impact items) yielded a 6-factor structure accounting for 67% of the variance for bloating (6 items), flatulence (3), belching (2), bad breath (2), stomach rumbling (2), and difficult gas evacuation (2). Global score (0-100) was worse among IBS vs GPop (40 ± 15 vs 33 ± 17; p = 0.0016). At the second visit, the intraclass correlation coefficient of IGQ scores was between 0.71 and 0.86 (n = 67) for test-retest reliability and 0.61-0.87 (n = 64) for equivalence between electronic and paper versions of IGQ. The IGQ available in paper and electronic versions in 3 languages is a robust instrument for capturing and measuring GRS and their impact on daily life. Intestinal Gas Quesitonnaire (IGQ): a new tool to measure Gas-Related Symptoms and their impact on daily life

Genome-wide multi-trait analysis of irritable bowel syndrome and related mental conditions identifies 38 new independent variants

Irritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction frequently accompanied by mental conditions, including depression and anxiety. Despite showing substantial heritability and being partly determined by a genetic component, the genetic underpinnings explaining the high rates of comorbidity remain largely unclear and there are no conclusive data on the temporal relationship between them. Exploring the overlapping genetic architecture between IBS and mental conditions may help to identify novel genetic loci and biological mechanisms underlying IBS and causal relationships between them. We quantified the genetic overlap between IBS, neuroticism, depression and anxiety, conducted a multi-trait genome-wide association study (GWAS) considering these traits and investigated causal relationships between them by using the largest GWAS to date. IBS showed to be a highly polygenic disorder with extensive genetic sharing with mental conditions. Multi-trait analysis of IBS and neuroticism, depression and anxiety identified 42 genome-wide significant variants for IBS, of which 38 are novel. Fine-mapping risk loci highlighted 289 genes enriched in genes upregulated during early embryonic brain development and gene-sets related with psychiatric, digestive and autoimmune disorders. IBS-associated genes were enriched for target genes of anti-inflammatory and antirheumatic drugs, anesthetics and opioid dependence pharmacological treatment. Mendelian-randomization analysis accounting for correlated pleiotropy identified bidirectional causal effects between IBS and neuroticism and depression and causal effects of the genetic liability of IBS on anxiety. These findings provide evidence of the polygenic architecture of IBS, identify novel genome-wide significant variants for IBS and extend previous knowledge on the genetic overlap and relationship between gastrointestinal and mental disorders. The online version contains supplementary material available at 10.1186/s12967-023-04107-5

Electrocatalytic evaluation of DNA damage by superoxide radical for antioxidant capacity assessment

The integrity of DNA purine bases was herein used to evaluate the antioxidant capacity. Unlike other DNA-based antioxidant sensors reported so far, the damaging agent chosen was the O 2 radical enzymatically generated by the xanthine/xanthine oxidase system. An adenine-rich oligonucleotide was adsorbed on carbon paste electrodes and subjected to radical damage in the presence/absence of several antioxidant compounds. As a result, partial damage on DNA was observed. A minor product of the radical oxidation was identified by cyclic voltammetry as a diimine adenine derivative also formed during the electrochemical oxidation of adenine/guanine bases. The protective efficiency of several antioxidant compounds was evaluated after electrochemical oxidation of the remaining unoxidized adenine bases, by measuring the electrocatalytic current of NADH mediated by the adsorbed catalyst species generated. A comparison between O 2 and OH radicals as a source of DNA lesions and the scavenging efficiency of various antioxidant compounds against both of them is discussed. Finally, the antioxidant capacity of beverages was evaluated and compared with the results obtained with an optical method

Acute Stress Regulates Sex-Related Molecular Responses in the Human Jejunal Mucosa: Implications for Irritable Bowel Syndrome

Estrés agudo; Barrera intestinal; SexoEstrès agut; Barrera intestinal; SexeCute stress; Intestinal barrier; SexIrritable bowel syndrome (IBS) is a prevalent gastrointestinal disorder linked to intestinal barrier dysfunction and life stress. We have previously reported that female sex per se determines an increased susceptibility to intestinal barrier dysfunction after cold pain stress (CPS). We aimed to identify sex-related molecular differences in response to CPS in healthy subjects to understand the origin of sex bias predominance in IBS. In 13 healthy males and 21 females, two consecutive jejunal biopsies were obtained using Watson’s capsule, at baseline, and ninety minutes after CPS. Total mucosal RNA and protein were isolated from jejunal biopsies. Expression of genes related to epithelial barrier (CLDN1, CLDN2, OCLN, ZO-1, and ZO-3), mast cell (MC) activation (TPSAB1, SERPINA1), and the glucocorticoid receptor (NR3C1) were analyzed using RT-qPCR. NR3C1, ZO-1 and OCLN protein expression were evaluated through immunohistochemistry and western blot, and mucosal inflammation through MC, lymphocyte, and eosinophil numbering. Autonomic, hormonal, and psychological responses to CPS were monitored. We found an increase in jejunal MCs, a reduced CLDN1 and OCLN expression, and an increased CLDN2 and SERPINA1 expression 90 min after CPS. We also found a significant decrease in ZO-1, OCLN, and NR3C1 gene expression, and a decrease in OCLN protein expression only in females, when compared to males. CPS induced a significant increase in blood pressure, plasma cortisol and ACTH, and subjective stress perception in all participants. Specific and independent sex-related molecular responses in epithelial barrier regulation are unraveled by acute stress in the jejunum of healthy subjects and may partially explain female predominance in IBS.Supported in part by Fondo Europeo de Desarrollo Regional (FEDER), Fondo de Investigación Sanitaria and Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), Instituto de Salud Carlos III, Subdirección General de Investigación Sanitaria, Ministerio de Economiá y Competitividad: CM08/00229 (BL); CM10/00155 (MP); EII2011-0035, CD15/00010, and MV17-00043 (BKRJ.); FI12/00254 (ESR.), PI17/0190 (JS), PI12/00314 and PI15/00301 (CAC), CIBEREHD CB06/04/0021 (JS, CAC.); Vall d’Hebron Institut de Recerca, Programa de becas predoctorales Amics de Vall d’Hebron: PRED-VHIR-2014-018 (MF), PRED-VHIR-2016-53 34 (CPC.)

P53 wild-type colorectal cancer cells that express a fetal gene signature are associated with metastasis and poor prognosis

Current therapy against colorectal cancer (CRC) is based on DNA-damaging agents that remain ineffective in a proportion of patients. Whether and how non-curative DNA damage-based treatment affects tumor cell behavior and patient outcome is primarily unstudied. Using CRC patient-derived organoids (PDO)s, we show that sublethal doses of chemotherapy (CT) does not select previously resistant tumor populations but induces a quiescent state specifically to TP53 wildtype (WT) cancer cells, which is linked to the acquisition of a YAP1-dependent fetal phenotype. Cells displaying this phenotype exhibit high tumor-initiating and metastatic activity. Nuclear YAP1 and fetal traits are present in a proportion of tumors at diagnosis and predict poor prognosis in patients carrying TP53 WT CRC tumors. We provide data indicating the higher efficacy of CT together with YAP1 inhibitors for eradication of therapy resistant TP53 WT cancer cells. Together these results identify fetal conversion as a useful biomarker for patient prognosis and therapy prescription. The failure of chemotherapy in colorectal cancer is currently unclear. Here, the authors show that upon sub-lethal dose of chemotherapy wild-type p53 colorectal cancers acquire a quiescence-like phenotype and a YAP-dependent fetal-like intestinal stem cell state associated with a higher metastatic activity and poor prognosis in patients