Validation of an LC-MS/MS Method for Urinary Lactulose and Mannitol Quantification: Results in Patients with Irritable Bowel Syndrome

Chemistry of Bairui granules and its mechanisms in the protective effect against methotrexate-induced liver injury

BACKGROUND

Bairui granules (BRKL), a traditional Chinese medicine preparation, possess a range of pharmacological effects. However, its impact on methotrexate (MTX)-induced liver damage remains unexplored.

PURPOSE

The present work focused on investigating the potential protection of BRKL on MTX-induced liver damage, along with its potential active ingredients and underlying mechanisms.

METHODS

We evaluated the hepatoprotective activities of BRKL in liver-damaged Wistar rats induced by intraperitoneal MTX injection, observing the liver's morphological and pathological features. Additionally, we measured serum ALT, AST, and LDH levels using kits. Ultra High-Performance Liquid Chromatography-Q-Exactive Orbitrap Mass Spectrometry (UHPLC-Q-Exactive Orbitrap MS) analyzed BRKL composition, and network pharmacology strategy predicted and analyzed BRKL's targets and pathways. Thereafter, we conducted molecular docking for analyzing affinity of bioactive ingredients for targets with Autodock. At last, results were verified through in vitro experiments.

RESULTS

The animal experiments revealed the significant protection of BRKL against MTX-mediated rat liver damage. A total of 64 major chemical constituents were identified in BRKL by UHPLC-Q-Exactive Orbitrap MS. We then applied the network-based pharmacological strategy to clarify BRKL's molecular mechanism on liver damage based on the identified components. The targets EGFR, SRC, PIK3R1, AKT1, and ESR1, as well as compounds isorhamnetin 3,7-O-diglucoside, β-ecdysone, chrysoeriol, apigenin, and diosmetin, may play pivotal roles in treating MTX-mediated liver damage. According to our in vitro experiments, isorhamnetin 3,7-O-diglucoside may exert its liver-protective effect via AKT/NF-κB pathway.

CONCLUSION

BRKL protected against MTX-mediated liver injury, and the bioactive ingredients, key pathways, and liver injury-related molecular targets have been identified. These findings provide new insights into using BRKL in treating liver damage and propose a feasible approach to exploring phytomedicine's chemical and pharmacological foundation.

Chemical profiling of Oxalis species growing wild in Egypt using HRLC/MS Spectrometry

Diabetes is a chronic metabolic disease that creates high blood sugar level. Therefore, diabetes awareness is necessary to prevent diabetes by reducing sugar intake and using low-calorie alternative sweeteners instead. Stevia rebaudiana is a medicinal plant species belonging to the Compositae family. It is a sweet herb that contains diterpene glycosides, which are directly responsible for the sweet taste, but they have no caloric value. Since ancient times, there have been several reports on the use of S. rebaudiana as an alternative sweetener and extended research has been conducted on its phytochemicals and biological activities. The plant contains a good number of phytochemicals with significant biological activities, namely polyphenolic derivatives, diterpenes glycosides, alkaloids, glycosides, tannins, chlorophylls, carotenoids, etc. For industrial use, those phytochemicals could be extracted from the selected plant and used for the preparation of nutraceuticals and food additives. S. rebaudiana is a natural herb; therefore, it has fewer or minimal adverse effects on human health. The selected plant in various forms is used for the treatment of diabetes, colon cancer, obesity, cavities, and others. However, the literature review shows that the information on this plant and its uses is not systematic. The purpose of the present review is to explore the status of phytochemicals and biological activities of the selected plant for young researchers. Therefore, the updated data will help them to develop new nutraceuticals and food additives that could help in the production of pharmaceuticals to treat different ailments.

Intestinal Permeability in Children with Functional Gastrointestinal Disorders: The Effects of Diet

Functional gastrointestinal disorders (FGIDs) are very common and life-impacting in children and young adults, covering 50% of pediatric gastroenterologist consultations. As it is known, FGIDs may be due to alterations in the gut–brain axis, dysbiosis and dysregulation of intestinal barrier, causing leaky gut. This may enhance increased antigen and bacterial passage through a damaged mucosa, worsening the impact of different medical conditions such as FGIDs. Little is known about the role of nutrients in modifying this “barrier disruption”. This narrative review aims to analyze the clinical evidence concerning diet and Intestinal Permeability (IP) in FGIDs in children. We searched the PubMed/Medline library for articles published between January 2000 and November 2021 including children aged 0–18 years old, using keywords related to the topic. Since diet induces changes in the intestinal barrier and microbiota, we aimed at clarifying how it is possible to modify IP in FGIDs by diet modulation, and how this can impact on gastrointestinal symptoms. We found that) is that small changes in eating habits, such as a low-FODMAP diet, an adequate intake of fiber and intestinal microbiota modulation by prebiotics and probiotics, seem to lead to big improvements in quality of life.

Healthy and pro-inflammatory gut ecology plays a crucial role in the digestion and tolerance of a novel Gluten Friendly™ bread in celiac subjects: a randomized, double blind, placebo control in vivo study

Gluten Friendly™ (GF) is a new gluten achieved through a physicochemical process applied to wheat kernels. The goal of this research was to assess the in vivo effects of Gluten Friendly™ bread on celiac gut mucosa and microbiota. In a double-blind placebo-controlled intervention study, 48 celiac disease (CD) patients were randomized into 3 groups to eat 100 g of bread daily, containing different doses (0; 3 g; 6 g) of GF for 12 weeks. The small-bowel morphology (VH/CrD), intraepithelial densities of CD3+, celiac serology, MUC2, CB1, gut permeability, proinflammatory cytokines, gluten in stools, symptoms, and gut microbial composition were assessed. All 48 CD subjects experienced no symptoms. K-means analysis evidenced celiac subjects clustering around unknown parameters independent of GF dosage: K1 35%; K2 30%; K3 35%. VH/CrD significantly decreased in K1 and K2. VH/CrD did not correlate with IEL increase in K2. 33-mer was not detected in 47% and 73% of patients in both K1 and K2, respectively. VH/CrD and IEL did not change significantly and strongly correlated with the absence of 33-mer in K3. Inflammation and VH/CrD decrease are strongly related with the presence of proinflammatory species at the baseline. A boost in probiotic, butyrate-producing genera, is strongly related with GF tolerance at the end of the trial. Our research suggests that a healthy and proinflammatory ecology could play a crucial role in the digestion and tolerance of the new gluten molecule in celiac subjects. However, GF can be completely digested by gut microbiota of CD subjects and shapes it toward gut homeostasis by boosting healthy butyrate-producing populations. The clinical trial registry number is NCT03137862 (https://clinicaltrials.gov).

Intestinal barrier dysfunction in irritable bowel syndrome: a systematic review

BACKGROUND AND AIM

Irritable bowel syndrome (IBS) is a complex and heterogeneous disorder. Sensory, motor and barrier dysfunctions are the key physiological endophenotypes of IBS. Our aim is to review studies evaluating barrier dysfunction in adults and children with IBS, as well as to link those changes with IBS symptomatology and quality of life.

METHODS

A comprehensive and systematic review of multiple databases was performed up to March 2020 to identify studies comparing intestinal permeability in IBS patients with healthy controls. Both in vivo and in vitro studies were considered.

RESULTS

We identified 66 studies, of which 27 used intestinal probes to quantify barrier function. The prevalence of barrier dysfunction differed between PI-IBS (17-50%), IBS-D (37-62%) and IBS-C (4-25%). At a group level, permeability was increased compared with healthy controls in IBS-D (9/13 studies) and PI-IBS (4/4 studies), but only a minority of IBS-C (2/7 studies) and not in the only IBS-M study. All four studies in children with IBS demonstrated loss of barrier function. A heterogeneous set of tight junction genes were found to be altered in small and large intestines of adults with IBS, but these have not been evaluated in children. Positive associations were identified between barrier dysfunction and bowel disturbances (6/9 studies), abdominal pain (9/13 studies), overall symptom severity (1/6 studies), depression and anxiety (1/1 study) and quality of life (1/4 studies). Fecal slurry or supernatants of IBS patients were found to induce barrier disruption in animal models (5/6 studies).

CONCLUSIONS

Barrier dysfunction is present in a significant proportion of adult and all pediatric IBS studies, especially in the IBS-D and PI-IBS subtype. The majority of studies indicated a positive association between loss of barrier function and symptoms such as abdominal pain and changes in the bowel function.

Application of metabolomics to the study of irritable bowel syndrome

The pathophysiology of irritable bowel syndrome and the detection of biomarkers of specific mechanisms and/or predictors of therapeutic response remain elusive. This roadblock reflects, in large part, the complexity and heterogeneity of the disorder. Recently, there has been growing evidence of a dietary and/or microbiome interaction with the host that may trigger symptoms in a subset of patients. While a number of techniques are available to examine these potential interactions, "omic" approaches such as metabolomics are becoming more widely used. Metabolomics measures hundreds and potentially thousands of known and unknown small molecule chemicals (metabolites) to provide a unique look into mechanisms that underlie symptom generation and potential predictors of therapeutic response. In this issue of the journal, Lee et al use nuclear magnetic resonance (NMR) to demonstrate the value of this approach to study IBS. This review examines the use of metabolomics to better understand IBS, focusing on what has been learned to date, practical and technical considerations, its potential for future research and how the study by Lee et al have contributed to these concepts.

Increased Colonic Permeability and Lifestyles as Contributing Factors to Obesity and Liver Steatosis

Intestinal permeability (IP) is essential in maintaining gut-metabolic functions in health. An unequivocal evaluation of IP, as marker of intestinal barrier integrity, however, is missing in health and in several diseases. We aimed to assess IP in the whole gastrointestinal tract according to body mass index (BMI) and liver steatosis. In 120 patients (61F:59M; mean age 45 ± SEM 1.2 years, range: 18-75), IP was distinctively studied by urine recovery of orally administered sucrose (SO, stomach), lactulose/mannitol ratio (LA/MA, small intestine), and sucralose (SA, colon). By triple quadrupole mass-spectrometry and high-performance liquid chromatography, we measured urinary recovery of saccharide probes. Subjects were stratified according to BMI as normal weight, overweight, and obesity, and answered questionnaires regarding dietary habits and adherence to the Mediterranean Diet. Liver steatosis was assessed by ultrasonography. IP at every gastrointestinal tract was similar in both sexes and decreased with age. Stomach and small intestinal permeability did not differ according to BMI. Colonic permeability increased with BMI, waist, neck, and hip circumferences and was significantly higher in obese than in lean subjects. As determined by logistic regression, the odds ratio (OR) of BMI increment was significantly higher in subjects in the highest tertile of sucralose excretion, also after adjusting for age and consumption of junk food. The presence of liver steatosis was associated with increased colonic permeability. Patients with lower score of adherence to Mediterranean diet had a higher score of 'junk food'. Intestinal permeability tended to increase in subjects with a lower adherence to Mediterranean diet. In conclusion, colonic (but not stomach and small intestinal) permeability seems to be linked to obesity and liver steatosis independently from dietary habits, age, and physical activity. The exact role of these last factors, however, requires specific studies focusing on intestinal permeability. Results should pave the way to both primary prevention measures and new therapeutic strategies in metabolic and liver diseases.

Urinary Peptidomic Biomarkers in Kidney Diseases

In order to effectively develop personalized medicine for kidney diseases we urgently need to develop highly accurate biomarkers for use in the clinic, since current biomarkers of kidney damage (changes in serum creatinine and/or urine albumin excretion) apply to a later stage of disease, lack accuracy, and are not connected with molecular pathophysiology. Analysis of urine peptide content (urinary peptidomics) has emerged as one of the most attractive areas in disease biomarker discovery. Urinary peptidome analysis allows the detection of short and long-term physiological or pathological changes occurring within the kidney. Urinary peptidomics has been applied extensively for several years now in renal patients, and may greatly improve kidney disease management by supporting earlier and more accurate detection, prognostic assessment, and prediction of response to treatment. It also promises better understanding of kidney disease pathophysiology, and has been proposed as a “liquid biopsy” to discriminate various types of renal disorders. Furthermore, proteins being the major drug targets, peptidome analysis may allow one to evaluate the effects of therapies at the protein signaling pathway level. We here review the most recent findings on urinary peptidomics in the setting of the most common kidney diseases.

Palmitoylethanolamide and Cannabidiol Prevent Inflammation-induced Hyperpermeability of the Human Gut In Vitro and In Vivo-A Randomized, Placebo-controlled, Double-blind Controlled Trial

BACKGROUND AND AIMS

We aimed to examine, for the first time, the effect of cannabidiol (CBD) and palmitoylethanolamide (PEA) on the permeability of the human gastrointestinal tract in vitro, ex vivo, and in vivo.

METHODS

Flux measurements of fluorescein-labeled dextrans 10 (FD10) and fluorescein-labeled dextrans 4 (FD4) dextran across Caco-2 cultures treated for 24 hours with interferon gamma (IFNγ) and tumour necrosis factor alpha (TNFα) (10 ng·mL-1) were measured, with or without the presence of CBD and PEA. Mechanisms were investigated using cannabinoid receptor 1 (CB1), cannabinoid receptor 2 (CB2), transient receptor potential vanilloid 1 (TRPV1), and proliferator activated receptors (PPAR) antagonists and protein kinase A (PKA), nitric oxide synthase, phosphoinositide 3-kinases, extracellular signal-regulated kinases (MEK/ERK), adenylyl cyclase, and protein kinase C (PKC) inhibitors. Human colonic mucosal samples collected from bowel resections were treated as previously stated. The receptors TRPV1, PPARα, PPARδ, PPARγ, CB1, CB2, G-coupled protein receptor 55 (GPR55), G-coupled protein receptor 119 (GPR119), and claudins-1, -2, -3, -4, -5, -7, and -8 mRNA were measured using multiplex. Aquaporin 3 and 4 were measured using enzyme-linked immunosorbent assay (ELISA). A randomized, double-blind, controlled-trial assessed the effect of PEA or CBD on the absorption of lactulose and mannitol in humans taking 600 mg of aspirin. Urinary concentrations of these sugars were measured using liquid chromatography mass spectrometry.

RESULTS

In vitro, PEA, and CBD decreased the inflammation-induced flux of dextrans (P < 0.0001), sensitive to PPARα and CB1 antagonism, respectively. Both PEA and CBD were prevented by PKA, MEK/ERK, and adenylyl cyclase inhibition (P < 0.001). In human mucosa, inflammation decreased claudin-5 mRNA, which was prevented by CBD (P < 0.05). Palmitoylethanolamide and cannabidiol prevented an inflammation-induced fall in TRPV1 and increase in PPARα transcription (P < 0.0001). In vivo, aspirin caused an increase in the absorption of lactulose and mannitol, which were reduced by PEA or CBD (P < 0.001).

CONCLUSION

Cannabidiol and palmitoylethanolamide reduce permeability in the human colon. These findings have implications in disorders associated with increased gut permeability, such as inflammatory bowel disease.

Increased Plasma Levels of Gut-Derived Phenolics Linked to Walking and Running Following Two Weeks of Flavonoid Supplementation

Using a randomized, double-blinded, placebo-controlled, parallel group design, this investigation determined if the combination of two weeks of flavonoid supplementation (329 mg/day, quercetin, anthocyanins, flavan-3-ols mixture) and a 45-minute walking bout (62.2 ± 0.9% VO2max (maximal oxygen consumption rate)) enhanced the translocation of gut-derived phenolics into circulation in a group of walkers (n = 77). The walkers (flavonoid, placebo groups) were randomized to either sit or walk briskly on treadmills for 45 min (thus, four groups: placebo⁻sit, placebo⁻walk, flavonoid⁻sit, flavonoid⁻walk). A comparator group of runners (n = 19) ingested a double flavonoid dose for two weeks (658 mg/day) and ran for 2.5 h (69.2 ± 1.2% VO2max). Four blood samples were collected (pre- and post-supplementation, immediately post- and 24 h post-exercise/rest). Of the 76 metabolites detected in this targeted analysis, 15 increased after the 2.5 h run, and when grouped were also elevated post-exercise (versus placebo⁻sit) for the placebo⁻ and flavonoid⁻walking groups (p < 0.05). A secondary analysis showed that pre-study plasma concentrations of gut-derived phenolics in the runners were 40% higher compared to walkers (p = 0.031). These data indicate that acute exercise bouts (brisk walking, intensive running) are linked to an increased translocation of gut-derived phenolics into circulation, an effect that is amplified when combined with a two-week period of increased flavonoid intake or chronic training as a runner.

Validation of UPLC-MS/MS Method for Determination of Urinary Lactulose/Mannitol

Determination of urinary lactulose/mannitol is one of the most used tests to evaluate intestinal barrier function. High-performance liquid chromatography (HPLC) separation with electrospray ionization tandem mass spectrometry guarantees high levels of selectivity and reproducibility. In this paper we report an upgrade of the previous published liquid chromatography tandem mass spectrometry method, introducing more reliable internal standards and ultra-performance liquid chromatography with ethylene bridged hybrid amide columns. The ultra-performance liquid chromatography provided an efficient chromatographic separation of the two sugars in 5 min, compared to 15 min using the previous method. The limit of quantification was 10 µg/mL for mannitol and 2.5 µg/mL for lactulose, and the assay was linear up to 1000 µg/mL for mannitol and 1000 µg/mL for lactulose. The within-run precision and accuracy ranged from 0.7 to 2.9% and 97.2 to 101.2%, respectively. The between-run precision and accuracy ranged from 1.9 to 4.7% and 94.8 to 97.5%, respectively. Recovery was higher than 90.2% for both lactulose and mannitol, and the matrix effect for both lactulose and mannitol was lower than 15%. With this new method we have a real improvement in terms of accuracy and reproducibility, ensuring results in shorter time. The changes to the previous protocol make this method excellent for routine purposes.