Micronutrient Deficiency in Inflammatory Bowel Diseases: Cause or Effect?

Gut dysbiosis in Crohn's disease: Never so close to solving the chicken-and-egg enigma: Commentary to "Gut microbiome composition is associated with future onset of Crohn's disease in healthy first-degree relatives, by Raygoza Garay JA et al., Gastroenterology 2023"

Crohn's disease (CD) is a chronic disease of the digestive tract whose pathogenesis remains not fully understood. Several studies have implicated the gut microbiota as a key player in the onset of gut inflammation. However, most of the data is based on case-control studies comparing patients with established disease with controls, usually healthy individuals. The study by Raygoza Garay and colleagues shows for the first time that changes in the composition of the gut microbiota precede CD onset by up to five years. The authors developed a microbiome risk score using a machine-learning model that included bacterial composition and clinical variables from a large cohort of healthy first-degree relatives of patients with CD. This study provides strong evidence that the alterations of the gut microbiota is causal in CD pathogenesis and suggest that early intervention targeting it may be an appropriate preventive strategy.

Gut Microbiome Composition Is Associated With Future Onset of Crohn's Disease in Healthy First-Degree Relatives

BACKGROUND & AIMS

The cause of Crohn's disease (CD) is unknown, but the current hypothesis is that microbial or environmental factors induce gut inflammation in genetically susceptible individuals, leading to chronic intestinal inflammation. Case-control studies of patients with CD have cataloged alterations in the gut microbiome composition; however, these studies fail to distinguish whether the altered gut microbiome composition is associated with initiation of CD or is the result of inflammation or drug treatment.

METHODS

In this prospective cohort study, 3483 healthy first-degree relatives (FDRs) of patients with CD were recruited to identify the gut microbiome composition that precedes the onset of CD and to what extent this composition predicts the risk of developing CD. We applied a machine learning approach to the analysis of the gut microbiome composition (based on 16S ribosomal RNA sequencing) to define a microbial signature that associates with future development of CD. The performance of the model was assessed in an independent validation cohort.

RESULTS

In the validation cohort, the microbiome risk score (MRS) model yielded a hazard ratio of 2.24 (95% confidence interval, 1.03-4.84; P = .04), using the median of the MRS from the discovery cohort as the threshold. The MRS demonstrated a temporal validity by capturing individuals that developed CD up to 5 years before disease onset (area under the curve > 0.65). The 5 most important taxa contributing to the MRS included Ruminococcus torques, Blautia, Colidextribacter, an uncultured genus-level group from Oscillospiraceae, and Roseburia.

CONCLUSION

This study is the first to demonstrate that gut microbiome composition is associated with future onset of CD and suggests that gut microbiome is a contributor in the pathogenesis of CD.

Mitigating Effects of Tenebrio molitor Larvae Powder Administration in Mice with Dextran Sodium Sulfate (DSS)- Induced Colitis

BACKGROUND

Ulcerative colitis (UC) is an inflammatory bowel disease that affects people worldwide. The causes of UC are diverse, and symptoms include diarrhea, weight loss, anemia, rectal bleeding, and bloody stools. Tenebrio molitor larvae have recently gained attention as edible insects with various physiological and medical effects. Research on the anti-inflammatory effects of ingesting Tenebrio molitor larvae powder (TMLP) is being actively conducted. In this study, TMLP was administered to mice with dextran sodium sulfate (DSS)-induced colitis to investigate its effects in reducing colitis symptoms.

METHODS

Mice were initially given 3% DSS in water to induce colitis and then feed containing 0%, 2%, or 4% TMLP. Pathologic changes in colon tissues were assessed by histology, and neutrophil levels were measured by myeloperoxidase (MPO) assay. Levels of IL-1β, IL-6, and TNF-α were measured using real-time PCR and ELISA assays, and IκB and NF-kB protein levels were measured by western blotting.

RESULT

Disease Activity Index (DAI) scores and MPO activity were reduced in TMLP-treated mice, and colon length increased as much as normal mice. Pathologic changes in the colon tissues of DSS-induced mice were attenuated, and the expression of inflammatory cytokine genes IL-1β, IL-6, and TNF-α decreased. Concomitant decreases in the protein expression of IL-1β and IL-6 were confirmed using ELISA. Western blotting revealed that levels of phosphorylated forms of IκB and NF-κB also decreased.

CONCLUSION

These results show that feeding TMLP to DSS-induced mice inhibited the typical inflammatory pathway of colitis. Therefore, TMLP shows potential as a food additive that can help treat colitis.
.

Atherosclerotic Cardiovascular Disease in Inflammatory Bowel Disease: The Role of Chronic Inflammation and Platelet Aggregation

Background and Objectives: Atherosclerosis is one of inflammatory bowel disease’s most significant cardiovascular manifestations. This research aimed to examine the relationship between biochemical, haemostatic, and immune parameters of atherosclerosis and ulcerative colitis patients and its relationship to platelet aggregation. Materials and Methods: A clinical, observational cross-sectional study was performed, during which the tested parameters were compared in the experimental and control groups. The patients were divided into four groups. The first group had 25 patients who had ulcerative colitis and atherosclerosis. The second group included 39 patients with ulcerative colitis without atherosclerosis. The third group comprised 31 patients suffering from atherosclerosis without ulcerative colitis, and the fourth group comprised 25 healthy subjects. Results: In our study, we registered statistically higher levels of inflammatory markers like SE, CRP, Le, fecal calprotectin, TNF-α, and IL-6, as well as the higher value of thrombocytes and thrombocyte aggregation in the group of patients with ulcerative colitis compared to the control group. Lower levels of total cholesterol and LDL were also recorded in patients with ulcerative colitis and atherosclerosis and ulcerative colitis without atherosclerosis compared to healthy control. Triglyceride and remnant cholesterol were higher in patients with ulcerative colitis and atherosclerosis when compared to patients with ulcerative colitis and healthy control but lower than in patients with atherosclerosis only. Conclusions: Several inflammatory markers and platelet aggregation could be good discrimination markers for subjects with ulcerative colitis with the highest risk of atherosclerosis.

Genetic Aspects of Micronutrients Important for Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), Crohn’s disease (CD) and ulcerative colitis (UC) are complex diseases whose etiology is associated with genetic and environmental risk factors, among which are diet and gut microbiota. To date, IBD is an incurable disease and the main goal of its treatment is to reduce symptoms, prevent complications, and improve nutritional status and the quality of life. Patients with IBD usually suffer from nutritional deficiency with imbalances of specific micronutrient levels that contribute to the further deterioration of the disease. Therefore, along with medications usually used for IBD treatment, therapeutic strategies also include the supplementation of micronutrients such as vitamin D, folic acid, iron, and zinc. Micronutrient supplementation tailored according to individual needs could help patients to maintain overall health, avoid the triggering of symptoms, and support remission. The identification of individuals’ genotypes associated with the absorption, transport and metabolism of micronutrients can modify future clinical practice in IBD and enable individualized treatment. This review discusses the personalized approach with respect to genetics related to micronutrients commonly used in inflammatory bowel disease treatment.

Efficacy and Safety of Vitamin D Adjuvant Therapy for Ulcerative Colitis: A Meta-Analysis

Objective

To examine the clinical efficacy and safety of Vitamin D in the treatment of ulcerative colitis in a systematic manner.

Methods

RCT studies on Vitamin D in the treatment of ulcerative colitis were searched from CNKI, Wanfang Data, PubMed, Cochrane Library, and Web of Science databases. RevMan 5.4 software was used for analysis.

Results

10 articles were included, including 1077 patients. Meta-analysis results showed that when clinical efficacy was used as the outcome index, the clinical efficacy of the oral vitamin group was higher than that of the conventional treatment group (OR = 4.07, 95% CI 2.64-6.27), and the difference was statistically significant (Z = 6.38, P < 0.00001). When the Mayo risk score was used as the outcome index, the difference was statistically significant, indicating that oral Vitamin D significantly reduced the Mayo risk score (MD: -0.41, CI = (−0.47, −0.34), Z = 13.09, P < 0.00001). Using the intestinal mucosal barrier as the outcome index, the results showed that (1) the MDA group (MD = −0.75, 95% CI (-0.96~-0.53), P < 0.00001), (2) the DAO group (MD = −1.17, 95% CI (-1.39-0.95), P < 0.00001), and the Vitamin D group could effectively improve intestinal mucosal barrier function after sensitivity analysis (MD = −1.00, 95% CI (-1.08-0.92), P < 0.00001). When inflammatory factors were used as outcome indicators, IL-6, TNF-α, and CRP groups had statistical significance (MD = −4.50, 95% CI (-5.13-3.87), P < 0.00001); MD = −7.27, 95% CI (18.96-5.58), P < 0.00001; and MD = −1.49, 95% CI (-1.76~-1.23), P < 0.00001, respectively). When the incidence of adverse reactions was used as the outcome indicator (OR = 0.73, 95% CI (0.34-1.32), P = 0.23), there was no significant difference between the two groups.

Conclusion

Vitamin D combined with mesalazine is effective in the treatment of ulcerative colitis, by improving the Mayo score and intestinal barrier function, and reducing inflammatory factors, with no significant safety difference. However, due to the quality of the included researches, more RCT researches needed to provide sufficient evidence to support clinical application. This study is registered with INPLASY 202250044.

Fecal Microbiome Changes and Specific Anti-Bacterial Response in Patients with IBD during Anti-TNF Therapy

Inflammatory bowel diseases (IBD) are chronic disorders of the gastrointestinal tract that have been linked to microbiome dysbiosis and immune system dysregulation. We investigated the longitudinal effect of anti-TNF therapy on gut microbiota composition and specific immune response to commensals in IBD patients. The study included 52 patients tracked over 38 weeks of therapy and 37 healthy controls (HC). To characterize the diversity and composition of the gut microbiota, we used amplicon sequencing of the V3V4 region of 16S rRNA for the bacterial community and of the ITS1 region for the fungal community. We measured total antibody levels as well as specific antibodies against assorted gut commensals by ELISA. We found diversity differences between HC, Crohn's disease, and ulcerative colitis patients. The bacterial community of patients with IBD was more similar to HC at the study endpoint, suggesting a beneficial shift in the microbiome in response to treatment. We identified factors such as disease severity, localization, and surgical intervention that significantly contribute to the observed changes in the gut bacteriome. Furthermore, we revealed increased IgM levels against specific gut commensals after anti-TNF treatment. In summary, this study, with its longitudinal design, brings insights into the course of anti-TNF therapy in patients with IBD and correlates the bacterial diversity with disease severity in patients with ulcerative colitis (UC).