Association of intestinal permeability with admission vitamin D deficiency in patients who are critically ill

Ozoile Reduces the LPS-Induced Inflammatory Response in Colonic Epithelial Cells and THP-1 Monocytes

Inappropriate activation of immune functions in intestinal epithelial cells can lead to inflammation that is characterized also by infiltration into intestinal tissue of monocytes/macrophages. Current therapies for intestinal inflammation include anti-inflammatory, immunosuppressive and biological drugs. Ozoile (stable ozonides) has been reported to exert anti-inflammatory effects. However, ozonated oil has been used mainly for topical applications and no data are available about its effects on intestinal cells or immune cells. In this study, we evaluated Ozoile effects on human HT-29 colonic cells and THP-1 monocytic cells stimulated with LPS to induce inflammation. HT-29 and THP-1 cells were treated with LPS in the presence/absence of Ozoile for 4 h. Biomarkers of inflammation, some members of tight junctions and the adhesion molecule ICAM were assessed by qRT-PCR. Protein expression was analyzed by Western blotting. The release of TNF-α and IL-1β was measured by ELISA. In HT-29, Ozoile inhibited LPS-induced expression of TNF-α, IL-1β, ZO-1, CLDN1, NOS2 and MMP-2 and increased the expression of Nrf2 and SOD2 antioxidant proteins. In THP-1 cells, the LPS induction of TNF-α, IL-1β and ICAM was counteracted by Ozoile treatment. Our in vitro results demonstrate the effectiveness of Ozoile in reducing the inflammatory response in intestinal and monocytic cells. Further in vivo studies are necessary to confirm its possible use for intestinal inflammatory conditions.

Nutrition in inflammatory bowel diseases; Is there a role?

Nutrition is of paramount importance not only for healthy individuals, but all the more for the ones with pathologies interlinked with the diet. In that light, diet, when used accordingly can act in a protective manner in inflammatory bowel diseases. The interplay of diet and IBD is not thoroughly defined, and guidelines are a work in progress. However, significant knowledge has been gained with regard to foods and nutrients that may exacerbate or alleviate the core symptoms. Patients with IBD restrict from their diet a plethora of foods often arbitrary, thus depriving themselves from valuable constituents. Careful navigation into the newfound field of genetic variants and personalization of diet should be employed with avoidance of the Westernized diet, processed foods and additives, and focus on a holistic approach with a balanced diet rich in bioactive compounds in order to improve the quality of life of these patients and address diet-related deficiencies.

The Pivotal Role of Aryl Hydrocarbon Receptor-Regulated Tight Junction Proteins and Innate Immunity on the Synergistic Effects of Postbiotic Butyrate and Active Vitamin D3 to Defense against Microbial Invasion in Salmonella Colitis

Our recent report illustrated the unitedly advantageous effects of postbiotic butyrate on active vitamin D3 (VD3)-orchestrated innate immunity in Salmonella colitis. There is growing awareness that aryl hydrocarbon receptor (AhR) can regulate intestinal immunity and barrier function, through modulating cecal inflammation and junction proteins expression. Hence, we researched the participation of AhR-regulated tight junction functions on the united effects of butyrate and VD3 on intestinal defense to Salmonella infection. Salmonella colitis model were elicited by oral gavage with 1 × 10⁸ CFU of a S. typhimurium wild-type strain SL1344 in C57BL/6 mice. Before and after the colitis generation, mice were fed with butyrate and/or VD3 by oral gavage in the absence or presence of intraperitoneal injection of AhR inhibitor for 4 and 7 days, respectively. We observed that butyrate and VD3 could concert together to reduce the invasion of Salmonella in colitis mice by enhancing cecal cytokines and antimicrobial peptides expression and reducing zonulin and claudin-2 protein expressions in mucosal stain, compared to single treatment, which were counteracted by AhR inhibitor. It implies that AhR is involved in the united effects of butyrate and VD3 on the intestinal defense to Salmonella infection in colitis mice. This study discloses the promising alternative therapy of combining postbiotic and VD3 for invasive Salmonellosis and the pivotal role of AhR pathway.

Assessment of Selected Intestinal Permeability Markers in Children with Food Allergy Depending on the Type and Severity of Clinical Symptoms

Background: Food allergy (FA) has a broad range of symptoms, and clinical manifestations may concern several reactions from one system or organ. Aim: The aim of the study was to assess intestinal permeability (IP) based on the analysis of serum zonulin and bacterial lipopolysaccharides (LPS) levels in children with FA, taking into account the pathomechanism of immune reaction, clinical symptoms of FA and their severity. Material and methods: The study comprised 103 patients aged 7–60 months (median 34); 49 children with IgE-mediated allergy and 25 children with non-IgE-mediated allergy; the reference group comprised 29 children with functional gastrointestinal disorders. IP markers were determined using ELISA. Results: There was no correlation between the severity of clinical symptoms and the level of IP markers in children with FA. Zonulin and LPS levels were significantly higher in children with FA and gastrointestinal symptoms. Zonulin levels in the subgroup of children with non-IgE-mediated FA and gastrointestinal symptoms were significantly higher than in the subgroup of children with IgE-mediated FA and these symptoms. The level of LPS was significantly higher in the subgroup with IgE-mediated FA and atopic dermatitis. Conclusions: Zonulin and LPS levels were significantly higher in children with FA compared to children from the reference group. Zonulin levels were significantly higher in children with non-IgE-mediated FA than in children with IgE-mediated FA.

Factors Modulating COVID-19: A Mechanistic Understanding Based on the Adverse Outcome Pathway Framework

Addressing factors modulating COVID-19 is crucial since abundant clinical evidence shows that outcomes are markedly heterogeneous between patients. This requires identifying the factors and understanding how they mechanistically influence COVID-19. Here, we describe how eleven selected factors (age, sex, genetic factors, lipid disorders, heart failure, gut dysbiosis, diet, vitamin D deficiency, air pollution and exposure to chemicals) influence COVID-19 by applying the Adverse Outcome Pathway (AOP), which is well-established in regulatory toxicology. This framework aims to model the sequence of events leading to an adverse health outcome. Several linear AOPs depicting pathways from the binding of the virus to ACE2 up to clinical outcomes observed in COVID-19 have been developed and integrated into a network offering a unique overview of the mechanisms underlying the disease. As SARS-CoV-2 infectibility and ACE2 activity are the major starting points and inflammatory response is central in the development of COVID-19, we evaluated how those eleven intrinsic and extrinsic factors modulate those processes impacting clinical outcomes. Applying this AOP-aligned approach enables the identification of current knowledge gaps orientating for further research and allows to propose biomarkers to identify of high-risk patients. This approach also facilitates expertise synergy from different disciplines to address public health issues.

Preventing Bacterial Translocation in Patients with Leaky Gut Syndrome: Nutrition and Pharmacological Treatment Options

Leaky gut syndrome is a medical condition characterized by intestinal hyperpermeability. Since the intestinal barrier is one of the essential components maintaining homeostasis along the gastrointestinal tract, loss of its integrity due to changes in bacterial composition, decreased expression levels of tight junction proteins, and increased concentration of pro-inflammatory cytokines may lead to intestinal hyperpermeability followed by the development of gastrointestinal and non-gastrointestinal diseases. Translocation of microorganisms and their toxic metabolites beyond the gastrointestinal tract is one of the fallouts of the leaky gut syndrome. The presence of intestinal bacteria in sterile tissues and distant organs may cause damage due to chronic inflammation and progression of disorders, including inflammatory bowel diseases, liver cirrhosis, and acute pancreatitis. Currently, there are no medical guidelines for the treatment or prevention of bacterial translocation in patients with the leaky gut syndrome; however, several studies suggest that dietary intervention can improve barrier function and restrict bacteria invasion. This review contains current literature data concerning the influence of diet, dietary supplements, probiotics, and drugs on intestinal permeability and bacterial translocation.

Effects of Vitamin D-Deficient Diet on Intestinal Epithelial Integrity and Zonulin Expression in a C57BL/6 Mouse Model

Background and Aims: Vitamin D (VD) plays an important role not only in mineral balance and skeletal maintenance but also in immune modulation. VD status was found correlated with the pathophysiology and severity of inflammatory bowel diseases and other autoimmune disorders. Epithelial barrier function is primarily regulated by the tight-junction (TJ) proteins. In this study, we try to establish an animal model by raising mice fed VD-deficient diet and to investigate the effects of VD-deficient diet on gut integrity and zonulin expression.

Methods: Male C57BL/6 mice were administered either VD-deficient [VDD group, 25(OH)₂D₃ 0 IU/per mouse] or VD-sufficient [VDS group, 25(OH)₂D₃ 37.8 IU/per mouse] special diets for 7 weeks. Body weight and diet intake were recorded weekly. Serum VD levels were detected. After sacrifice, jejunum and colon specimens were collected. The villus length and crypt depth of the jejunum as well as mucosa thickness of the colon were measured. Various serum pro-inflammatory cytokines and intestinal TJ proteins were assessed. The serum level of zonulin and the mRNA expression of jejunum zonulin were also investigated.

Results: We found that mice fed a VDD diet had a lower serum level of VD after 7 weeks (p < 0.001). VDD mice gained significant less weight (p = 0.022) and took a similar amount of diet (p = 0.398) when compared to mice raised on a VDS diet. Significantly decreased colon mucosa thickness was found in VDD mice compared with the VDS group (p = 0.022). A marked increase in serum pro-inflammatory cytokine levels was demonstrated in VDD mice. All relative levels of claudin (CLD)-1 (p = 0.007), CLD-3 (p < 0.001), CLD-7 (p < 0.001), and zonulin-1 (ZO-1, p = 0.038) protein expressions were significantly decreased in the VDD group when compared to the VDS group. A significant upregulation of mRNA expression of jejunum zonulin (p = 0.043) and elevated serum zonulin (p = 0.001) were found in the VDD group.

Conclusions: We successfully demonstrated that VDD could lead to impaired barrier properties. We assume that sufficient VD could maintain intestinal epithelial integrity and prevent mucosal barrier dysfunction. VD supplementation may serve as part of a therapeutic strategy for human autoimmune and infectious diseases with intestinal barrier dysfunction (leaky gut) in the future. To our knowledge, this is the first study to demonstrate that VDD could lead to a significant upregulation in mRNA expression of the jejunum zonulin level and also a marked elevation of serum zonulin in a mouse model.

The Relationship between Low Serum Vitamin D Levels and Altered Intestinal Barrier Function in Patients with IBS Diarrhoea Undergoing a Long-Term Low-FODMAP Diet: Novel Observations from a Clinical Trial

Decreased serum vitamin D (VD) levels have been associated with gastrointestinal (GI) disorders, including irritable bowel syndrome (IBS). VD can also modulate the intestinal barrier. Given the link between the GI barrier’s alterations and diet, attention has aroused the positive effects of the Low FODMAP Diet (LFD) on IBS patients’ symptom profile. We evaluated the GI symptoms and the urinary and circulating markers of GI barrier function, the markers of inflammation and intestinal dysbiosis in 36 IBS patients with predominant diarrhea (IBS-D) (5 men and 31 women, 43.1 ± 1.7 years) categorized for their circulating VD levels in low (L-VD) and normal (N-VD) (cutoff = 20 ng/mL). Evaluations were performed before and after 12 weeks of LFD. At the baseline, L-VD patients showed a significantly worse symptom profile and altered small intestinal permeability (s-IP) than N-VD. After LFD, a significant increase in the circulating VD levels in both the subgroups and a significant improvement of s-IP in L-VD patients occurred. Finally, VD levels negatively correlated with the symptom score and fecal zonulin. These data highlight the close relationship between VD and the intestinal barrier and support their involvement in IBS-D pathophysiology. Moreover, the potentially positive role of LFD in the management of IBS-D was confirmed.

Effects of Supplemental Calcium and Vitamin D on Circulating Biomarkers of Gut Barrier Function in Patients with Colon Adenoma: A Randomized Clinical Trial

Gut barrier dysfunction promotes chronic inflammation, contributing to several gastrointestinal diseases, including colorectal cancer. Preliminary evidence suggests that vitamin D and calcium could prevent colorectal carcinogenesis, in part, by influencing gut barrier function. However, relevant human data are scarce. We tested the effects of supplemental calcium (1,200 mg/day) and/or vitamin D3 (1,000 IU/day) on circulating concentrations of biomarkers of gut permeability (anti-flagellin and anti-lipopolysaccharide IgA and IgG, measured via ELISA) from baseline to 1 and 3 or 5 years postbaseline among 175 patients with colorectal adenoma in a randomized, double-blinded, placebo-controlled clinical trial. We also assessed factors associated with baseline concentrations of these biomarkers. We found no appreciable effects of supplemental vitamin D3 and/or calcium on individual or aggregate biomarkers of gut permeability. At baseline, a combined permeability score (the summed concentrations of all four biomarkers) was 14% lower among women (P = 0.01) and 10% higher among those who consumed >1 serving per day of red or processed meats relative to those who consumed none (P trend = 0.03). The permeability score was estimated to be 49% higher among participants with a body mass index (BMI) > 35 kg/m2 relative to those with a BMI < 22.5 kg/m2 (P trend = 0.17). Our results suggest that daily supplemental vitamin D3 and/or calcium may not modify circulating concentrations of gut permeability biomarkers within 1 or 3-5 years, but support continued investigation of modifiable factors, such as diet and excess adiposity, that could affect gut permeability. PREVENTION RELEVANCE: Calcium and vitamin D may be involved in regulating and maintaining the integrity of the intestinal mucosal barrier, the dysfunction of which results in exposure of the host to luminal bacteria, endotoxins, and antigens leading to potentially cancer-promoting endotoxemia and chronic colon inflammation. While our results suggest that daily supplementation with these chemopreventive agents does not modify circulating concentrations of gut permeability biomarkers, they support continued investigation of other potential modifiable factors, such as diet and excess adiposity, that could alter gut barrier function, to inform the development of treatable biomarkers of risk for colorectal neoplasms and effective colon cancer preventive strategies.

Serum Vitamins D, B9 and B12 in Greek Patients with Inflammatory Bowel Diseases

Deficiencies in vitamin D, folate and cobalamin are common in Inflammatory Bowel Disease (IBD). The aim of the present study was to assess serum levels of these vitamins in IBD adults based on the respective serum cut off values for vitamin deficiencies, and to explore possible associations with IBD-related biomarkers and nutritional intake. A cross-sectional study was carried out and patients with Crohn’s disease (CD) or ulcerative colitis (UC) from Attica-Greece were enrolled. Medical and dietary history, clinical examination and blood/stool biomarkers were evaluated. In total, 87 patients participated in the study. Serum levels of 25(OH)D, folate and cobalamin were deficient in 36.8%, 18.4% and 5.7% of patients, respectively. Linear regression analysis in the overall patients showed positive associations between (a) serum 25(OH)D with serum iron (beta = 0.083, p = 0.005) and (b) serum cobalamin with total bilirubin (beta = 0.357, p = 0.020) and direct bilirubin (beta = 0.727, p = 0.033), adjusting for age, sex, body mass index (BMI), disease activity and duration, smoking, nutritional intake and season of recruitment. In CD patients (N = 54), a negative linear association between serum folate and fecal lysozyme was evident (beta = −0.009, p = 0.020). No associations were found for UC patients (N = 33). The serum vitamin profile may be a complementary biomarker for the evaluation of disease activity next to serum and stool inflammatory biomarkers.

The Relationship of Vitamin D Status, Adherence to the Mediterranean Diet, and Physical Activity in Obese Children and Adolescents

Vitamin D deficiency is associated with a range of chronic diseases, including childhood obesity. Prevalence of vitamin D deficiency in obese children and adolescents ranges from 6.5% to 57%. This cross-sectional study included 92 obese patients with body mass index z-score >2 and 39 subjects in the control group. Anthropometric and laboratory patient assessment were performed, including the fasting 25-hydroxyvitamin D (25(OH)D). Adherence to the Mediterranean diet was assessed by Mediterranean Diet Quality Index for children and adolescents (KIDMED index), while physical activity was evaluated by Physical Activity Questionnaire (PAQ). Serum levels of 25(OH)D were significantly lower in obese subjects compared to the control group (52.0 ± 17.93 vs. 64.09 ± 25.82 nmol/L, P = .003). The subgroup of obese patients with metabolic syndrome (MS) had significantly lower levels of serum vitamin D when compared to the subgroup of obese patients without MS and the control group (46.99 ± 17.11 vs. 54.58 ± 17.93 vs. 64.09 ± 25.82 nmol/L, P = .003). Obese patients with MS had lower PAQ score when compared to obese without MS and the control group (2.32 ± 0.55 vs. 2.49 ± 0.67 vs. 2.85 ± 0.63 nmol/L, P = .002), while no significant differences were observed in the KIDMED index (4.23 ± 1.81 vs. 4.21 ± 2.13 vs. 4.87 ± 2.29, P = .251), respectively. PAQ score was in positive correlation with serum levels of 25(OH)D (r = 0.305, P < .001). This study demonstrated that obese children and adolescents have significantly lower values of serum 25(OH)D. The positive correlation between vitamin D and PAQ score points to the importance of physical activity in the prevention of further cardiovascular complications and MS.

The phenomenon of intestinal permeability and its association with cardiovascular disease. Current status

Changes in the intestinal permeability in various pathologies are widely discussed in the scientific community. There is still no consensus on whether high intestinal permeability can lead to chronic noncommunicable diseases, but there is much evidence that increased permeability can aggravate some of them. The article discusses a modern vision of the intestinal permeability including its potential contribution to the development of cardiovascular pathologies, which are the number one mortality cause both in Russia and around the world.