Vitamin D Receptor Gene Single Nucleotide Polymorphisms and Association With Vitamin D Levels and Endoscopic Disease Activity in Inflammatory Bowel Disease Patients: A Pilot Study

Associations between the VDR Gene rs731236 (TaqI) Polymorphism and Bone Mineral Density in Postmenopausal Women from the RAC-OST-POL

BACKGROUND

Postmenopausal osteoporosis is not only related to hormonal factors but is also associated with environmental and genetic factors. One of the latter is the polymorphism of vitamin D receptor (VDR). The aim of the reported study was to comprehensively analyze the VDR gene polymorphic variants rs731236 (TaqI), rs1544410 (BsmI) and rs7975232 (ApaI) in the Polish population of postmenopausal women.

METHODS

The study group consisted of 611 women after menopause (their median age was 65.82 ± 6.29 years). Each of them underwent bone densitometry (DXA) of the non-dominant femoral neck and total hip with a biochemical analysis of vitamin D3 serum concentration and genotyping of the above-mentioned single nucleotide polymorphisms (SNPs); the obtained results were analyzed in the aspect of waist circumference (WC), body mass index (BMI) and past medical history.

RESULTS

The genotype prevalence rates of all SNPs were compatible with Hardy-Weinberg equilibrium (p > 0.050). Out of the studied polymorphisms, only rs731236 genotype variants affected DXA, with AG heterozygotes showing the worst bone parameters. Neither patient age nor vitamin D3 concentration, BMI, WC or comorbidities was associated with rs731236 genotype.

CONCLUSIONS

Out of the polymorphisms studied, only rs731236 genotypes differed among the DXA results, while the AG heterozygotes were characterized by the lowest median bone mineral density.

The Impact of Outdoor in Nature Mindfulness on the Mental Well-being of Children and Adolescents. A Mental Health and Cross-cultural Approach

Background

Mindfulness, originating from ancient meditation practices, has garnered substantial scientific interest in recent decades due to its potential to enhance various aspects of well-being. The rise of scientific interest in mindfulness has led to the development of Mindfulness-Based Stress Reduction (MBSR) and other mindfulness-based interventions (MBIs), which have demonstrated positive effects on stress reduction, emotional regulation, and cognitive flexibility.

Objective

This study aimed to explore the characteristics and applications of mindfulness, investigate its impact on mental health, and assess the potential benefits of combining mindfulness with nature-based interventions in promoting the well-being of children and adolescents.

Methods

This review draws from existing literature, scholarly articles, and empirical studies related to mindfulness, nature exposure, and their effects on mental health.

Results

The results highlight the manifold benefits of mindfulness in different populations, including health professionals, patients, children, adolescents, and the general public. Mindfulness practice has been associated with notable reductions in stress, anxiety, and depression, and has shown positive effects on brain plasticity and cognitive functioning. Furthermore, the integration of mindfulness with exposure to natural environments holds potential for enhanced stress reduction and cognitive restoration.

Conclusion

The findings underscore the potential of mindfulness as a cost-effective and accessible intervention to promote mental health across diverse age groups and settings. Further research should explore the specific mechanisms and long-term effects of this integrated approach to optimize its benefits.

Lower vitamin D levels are associated with the pathogenesis of inflammatory bowel diseases

Vitamin D plays a role in regulating immune homeostasis, inflammation and has an impact on the pathogenesis of inflammatory bowel diseases (IBD). IBD has a multifactorial pathogenesis primarily associated with immune dysregulation, dysbiosis, structurally altered intestinal mucosa, and genetic factors. The immunomodulatory function of this vitamin is linked to its control over innate and adaptive immunity, facilitated through its nuclear vitamin D receptor, leading to the inhibition of nuclear factor kappa-B. This study aimed to investigate serum vitamin D levels in patients with IBD compared to healthy individuals and to evaluate the relationship between vitamin D and inflammatory markers. Cross-sectional study. The study included 106 participants divided into 2 groups: patients with IBD (92), and healthy controls (14). The diagnosis of IBD was based on clinical, laboratory, fecal, endoscopic, and histological findings, following the European guidelines for diagnosis and follow-up ECCO-ESGAR guidelines for diagnostic assessment of IBD from 2019. Serum vitamin D levels were measured along with laboratory tests, imaging, and endoscopic examinations. IBD activity was evaluated using the Montreal classification and clinical and endoscopic indices. Data analysis involved calculating the mean, minimum, and maximum values, standard deviation, and Pearson coefficient. The level of statistical significance for this study was set at P < .05. The study found a prevalence of vitamin D deficiency in 32.6% of patients with IBD, while 66.3% had insufficiency, as compared with healthy individuals. The mean levels of vitamin D in UC and CD were 16 ± 8.6 ng/mL, whereas in the control healthy group, they were 26 ± 9.73 ng/mL. A statistically significant reverse correlation was observed between lower vitamin D levels and higher levels of the inflammatory markers. The study concluded that IBD patients exhibit lower levels of vitamin D, which is associated with inflammation and may contribute to the pathogenesis of the disease.

Genotype Prevalence of Lactose Deficiency, Vitamin D Deficiency, and the Vitamin D Receptor in a Chilean Inflammatory Bowel Disease Cohort: Insights from an Observational Study

Lactose intolerance (LI) and vitamin D deficiency (VDD) have been linked to inflammatory bowel disease (IBD). We conducted an observational study in 192 Chilean IBD patients to investigate the prevalence of a specific gene variant (LCT-13910 CC genotype) associated with LI and the prevalence of VDD/Vitamin D Receptor (VDR) gene variants. Blood samples were analyzed using Illumina's Infinium Global Screening Array. The LCT-13910 CC genotype was found in 61% of IBD patients, similar to Chilean Hispanic controls and lower than Chilean Amerindian controls. The frequency of the LCT-13910-C allele in Chilean IBD patients (0.79) was comparable to the general population and higher than Europeans (0.49). Regarding VDR and VDD variants, in our study, the rs12785878-GG variant was associated with an increased risk of IBD (OR = 2.64, CI = 1.61-4.32; p-value = 0.001). Sixty-one percent of the Chilean IBD cohort have a genetic predisposition to lactose malabsorption, and a significant proportion exhibit genetic variants associated with VDD/VDR. Screening for LI and VDD is crucial in this Latin American IBD population.

[Mechanism of action and exogenous supplementation of vitamin D in Crohn's disease]

Vitamin D can not only regulate calcium and phosphorus metabolism, but also exert an immunoregulatory effect. Vitamin D deficiency is common in patients with Crohn's disease (CD). Studies have shown that vitamin D is associated with CD and other autoimmune diseases and can improve the condition of patients with CD and promote their recovery by regulating intestinal immunity, repairing the intestinal mucosal barrier, inhibiting intestinal fibrosis, enhancing the response to infliximab, and regulating intestinal microbiota. Exogenous vitamin D supplementation can induce disease remission while increasing the serum level of vitamin D. However, only a few randomized, double-blind, and placebo-controlled trials have investigated the therapeutic effect of vitamin D in CD, and the optimal form of vitamin D supplementation, the specific dosage of vitamin D supplementation, and the optimal serum maintenance concentration of vitamin D remain to be clarified. This article mainly discusses the mechanism of action of vitamin D in CD and the beneficial effect of exogenous vitamin D supplementation on CD.

A review of the critical role of vitamin D axis on the immune system

In recent years, the physiological and molecular functions of vitamin D (Vit-D) have been deeply investigated. At first, Vit-D was considered a regulator of mineral and skeletal homeostasis. However, due to the extensive-expression pattern of Vit-D receptor (VDR) in almost every non-skeletal cell, Vit-D is considered mainly a multifunctional agent with broad effects on various tissues, notably the immune system. The expression of VDR in immune cells such as dendritic cells, monocyte/macrophage, neutrophils, B cells and T cells has been well demonstrated. Besides, such immune cells are capable of metabolizing the active form of Vit-D which means that it can module the immune system in both paracrine and autocrine manners. Vit-D binding protein (DBP), that regulates the levels and homeostasis of Vit-D, is another key molecule capable of modulating the immune system. Recent studies indicate that dysregulation of Vit-D axis, variations in the DBP and VDR genes, and Vit-D levels might be risk factors for the development of autoimmune disease. Here, the current evidence regarding the role of Vit-D axis on the immune system, as well as its role in the development of autoimmune disease will be clarified. Further insight will be given to those studies that investigated the association between single nucleotide polymorphisms of DBP and VDR genes with autoimmune disease susceptibility.

Artificial Neural Network Analysis-Based Immune-Related Signatures of Primary Non-Response to Infliximab in Patients With Ulcerative Colitis

Infliximab (IFX) is an effective medication for ulcerative colitis (UC) patients. However, one-third of UC patients show primary non-response (PNR) to IFX. Our study analyzed three Gene Expression Omnibus (GEO) datasets and used the RobustRankAggreg (RRA) algorithm to assist in identifying differentially expressed genes (DEGs) between IFX responders and non-responders. Then, an artificial intelligence (AI) technology, artificial neural network (ANN) analysis, was applied to validate the predictive value of the selected genes. The results showed that the combination of CDX2, CHP2, HSD11B2, RANK, NOX4, and VDR is a good predictor of patients' response to IFX therapy. The range of repeated overall area under the receiver-operating characteristic curve (AUC) was 0.850 ± 0.103. Moreover, we used an independent GEO dataset to further verify the value of the six DEGs in predicting PNR to IFX, which has a range of overall AUC of 0.759 ± 0.065. Since protein detection did not require fresh tissue and can avoid multiple biopsies, our study tried to discover whether the key information, analyzed by RNA levels, is suitable for protein detection. Therefore, immunohistochemistry (IHC) staining of colonic biopsy tissues from UC patients treated with IFX and a receiver-operating characteristic (ROC) analysis were used to further explore the clinical application value of the six DEGs at the protein level. The IHC staining of colon tissues from UC patients confirmed that VDR and RANK are significantly associated with IFX efficacy. Total IHC scores lower than 5 for VDR and lower than 7 for RANK had an AUC of 0.828 (95% CI: 0.665-0.991, p = 0.013) in predicting PNR to IFX. Collectively, we identified a predictive RNA model for PNR to IFX and explored an immune-related protein model based on the RNA model, including VDR and RANK, as a predictor of IFX non-response, and determined the cutoff value. The result showed a connection between the RNA and protein model, and both two models were available. However, the composite signature of VDR and RANK is more conducive to clinical application, which could be used to guide the preselection of patients who might benefit from pharmacological treatment in the future.