Vitamin D Deficiency in the Gulf Cooperation Council: Exploring the Triad of Genetic Predisposition, the Gut Microbiome and the Immune System

Association of vitamin D deficiency and insufficiency with uncontrolled type 1 diabetes Mellitus among Saudi pediatric patients; a hospital-based retrospective study

Background

The association between 25-hydroxy-vitamin D [25(OH)D] levels and glycemic control in pediatric patients with type 1 diabetes mellitus (T1DM) is unclear. In this study, we aimed to investigate the association between 25(OH)D levels and glycemic control in Saudi pediatric patients' with T1DM in a region that is sunny year-round.

Materials and methods

A retrospective study was conducted in the Pediatric Department of King Saud Hospital in Unaizah, Saudi Arabia. A total of 218 children with T1DM were enrolled in the study and grouped according to their glycated hemoglobin (HbA1C) levels into the controlled T1DM (HbA1C ≤ 7.5%) and the uncontrolled T1DM (HbA1C > 7.5%). Their 25(OH)D levels and thyroid function were measured using standard methods.

Results

Of the 218 children in this study, 182 (83.5%) had uncontrolled T1DM, while only 36 (16.5%) had controlled T1DM. The median (interquartile range) of 25(OH)D levels was significantly lower in the uncontrolled T1DM group compared with the controlled group [45.4 (31.2-59.7) nmol/L vs. 56.1 (37.5-77.6) nmol/L; p = 0.007], respectively. Vitamin D deficiency (<50.0 nmol/L) and insufficiency (50-74 nmol/L) were detected in 55.0% and 31.1% of all the enrolled children, respectively. Vitamin D deficiency was detected in 86.6% of the uncontrolled T1DM patients and in 16.5% of the controlled T1DM patients (p = 0.012). The multivariable analysis showed that both vitamin D deficiency [adjusted odds ratio (aOR) = 2.92, p = 0.048] and insufficiency [aOR = 3.17, p = 0.042] were risk factors for uncontrolled diabetes.

Conclusion

Vitamin D deficiency was highly prevalent in the studied group. Both vitamin D deficiency and insufficiency are associated with uncontrolled T1DM. Further study is needed.

Cross-Sectional and Prospective Association of Serum 25-Hydroxyvitamin D with Gut Mycobiota during Pregnancy among Women with Gestational Diabetes

SCOPE

Little is known about the effect of blood vitamin D status on the gut mycobiota (i.e., fungi), a crucial component of the gut microbial ecosystem. The study aims to explore the association between 25-hydroxyvitamin D [25(OH)D] and gut mycobiota and to investigate the link between the identified mycobial features and blood glycemic traits.

METHODS AND RESULTS

The study examines the association between serum 25(OH)D levels and the gut mycobiota in the Westlake Precision Birth Cohort, which includes pregnant women with gestational diabetes mellitus (GDM). The study develops a genetic risk score (GRS) for 25(OH)D to validate the observational results. In both the prospective and cross-sectional analyses, the vitamin D is associated with gut mycobiota diversity. Specifically, the abundance of Saccharomyces is significantly lower in the vitamin D-sufficient group than in the vitamin D-deficient group. The GRS of 25(OH)D is inversely associated with the abundance of Saccharomyces. Moreover, the Saccharomyces is positively associated with blood glucose levels.

CONCLUSION

Blood vitamin D status is associated with the diversity and composition of gut mycobiota in women with GDM, which may provide new insights into the mechanistic understanding of the relationship between vitamin D levels and metabolic health.

Ethnic-Based Assessment of Vitamin D and Magnesium Status in the Kingdom of Bahrain

BACKGROUND

Vitamin D deficiency is a major global health problem. Most previous studies focused attention on the significant role of sunlight exposure in the homeostasis of vitamin D and calcium blood levels. Magnesium is pivotal in the proper functioning of vitamin D, and the physiologic functions of different organs require a balanced vitamin D and magnesium status. The relationship between sunlight exposure and blood levels of vitamin D and magnesium has often been overlooked. The aim of this study was to evaluate vitamin D and magnesium status based on sunlight exposure and ethnicity in Bahraini and expatriate workers.

METHODS

A cross-sectional study was conducted between October 2018 and September 2019. One hundred and seventy-four subjects participated in this study were subdivided based on their ethnicity and work environment-dependent exposure to sunlight into four groups: (1) Bahraini exposed (n=94), (2) Bahraini non-exposed (n=25), (3) expatriate exposed (n=31), and (4) expatriate non-exposed (n=24). Blood levels of vitamin D and magnesium were evaluated for all the participants.

RESULTS

 Independent of ethnicity, vitamin D levels were insignificantly different among the studied groups and were all below the normal reference range. Yet, there was still a sunlight-dependent increase in vitamin D level that could be seen only in Bahraini workers. Magnesium levels were significantly higher in expatriates when compared to Bahraini workers. Sunlight-exposed expatriates had significantly higher magnesium levels than their Bahraini counterparts, while there was no significant difference between both ethnicities in the non-exposed groups.

CONCLUSION

Country- and ethnic-specific definitions for vitamin D status and sunlight exposure are recommended. The assessment of magnesium status is pivotal in the overall assessment of vitamin D status.

Role of gut-microbiota in disease severity and clinical outcomes

A delicate balance of nutrients, antigens, metabolites and xenobiotics in body fluids, primarily managed by diet and host metabolism, governs human health. Human gut microbiota is a gatekeeper to nutrient bioavailability, pathogens exposure and xenobiotic metabolism. Human gut microbiota starts establishing during birth and evolves into a resilient structure by adolescence. It supplements the host's metabolic machinery and assists in many physiological processes to ensure health. Biotic and abiotic stressors could induce dysbiosis in gut microbiota composition leading to disease manifestations. Despite tremendous scientific advancements, a clear understanding of the involvement of gut microbiota dysbiosis during disease onset and clinical outcomes is still awaited. This would be important for developing an effective and sustainable therapeutic intervention. This review synthesizes the present scientific knowledge to present a comprehensive picture of the role of gut microbiota in the onset and severity of a disease.

Investigating the relationship between vitamin-D deficiency and glycemia status and lipid profile in nondiabetics and prediabetics in Saudi population

Vitamin D deficiency increases the risk of developing diabetes, dyslipidemia, and other chronic diseases. We aimed to investigate the relationship between vitamin D deficiency, glycemic levels, and lipid profiles in individuals with prediabetes and nondiabetes. This observational cross-sectional study was conducted on 249 adults who were divided into 2 groups based on the American Diabetes Association classification: nondiabetics and prediabetics. The serum vitamin D levels, lipid profiles, fasting blood glucose levels, hemoglobin A1c levels, fasting insulin levels, and insulin resistance (IR) were evaluated. The prevalence of vitamin D deficiency in all participants was 30.9%, and mean vitamin D levels were significantly [P = .0004] lower in prediabetics, who were more common in females. Furthermore, prediabetics had significantly higher serum triglycerides [P = .0006], and significantly lower serum high-density lipoprotein levels [P = .0148] than those nondiabetics. Serum cholesterol and low-density lipoprotein levels did not differ significantly between the 2 groups. 31.4% of all participants were overweight and 40.2% were obese. Furthermore, there was a strong correlation between vitamin D levels and IR and body mass indices ≥ 25 in prediabetics [r = -0.92] [P < .001]. Finally, vitamin D levels had a significant inverse relationship with glycemic parameters and IR, particularly in obese participants, but there was no significant relationship with lipid profile. In conclusion, vitamin D deficiency is common in females, regardless of whether they are prediabetics, but is more prevalent in prediabetics. Vitamin D deficiency is associated with high triglycerides and low high-density lipoprotein levels, but there were no significant changes in total cholesterol or low-density lipoprotein levels. Furthermore, vitamin D levels were negatively correlated with both fasting blood glucose and hemoglobin A1c levels, and its deficiency was strongly associated with IR especially in obese patients despite there being no significant correlation with blood lipids.

Genes and Microbiota Interaction in Monogenic Autoimmune Disorders

Monogenic autoimmune disorders represent an important tool to understand the mechanisms behind central and peripheral immune tolerance. Multiple factors, both genetic and environmental, are known to be involved in the alteration of the immune activation/immune tolerance homeostasis typical of these disorders, making it difficult to control the disease. The latest advances in genetic analysis have contributed to a better and more rapid diagnosis, although the management remains confined to the treatment of clinical manifestations, as there are limited studies on rare diseases. Recently, the correlation between microbiota composition and the onset of autoimmune disorders has been investigated, thus opening up new perspectives on the cure of monogenic autoimmune diseases. In this review, we will summarize the main genetic features of both organ-specific and systemic monogenic autoimmune diseases, reporting on the available literature data on microbiota alterations in these patients.

Probability of Concurrent Deficiency of Vitamin D and Iron in Hypothyroidism: A Cross-Sectional Study

BACKGROUND

Hypothyroidism is the most common pathophysiological condition that affects mostly females in both developed and developing countries. Data on hypothyroidism among adult females are essential to understand the underactive status of the thyroid gland among the female population and its correlated effects on a deficiency of vitamin D and iron, as effective prevention of osteoporotic changes and iron deficiency anemia is possible. Therefore, the present study was designed to investigate the probability of concurrent iron and vitamin D deficiency among the adult hypothyroid female population of Abu Dhabi, UAE.

MATERIALS AND METHODS

This cross-sectional study was carried out from September 2019 to July 2021 among 500 adult females aged 18 to 45 years old in Sheikh Shakhbout Medical City (SSMC) and Sheikh Khalifa Medical City (SKMC), Abu Dhabi, UAE. After obtaining written informed consent, subjects' demographic characteristics (sun exposure, dressing code, food consumption), anthropometry (height, weight, BMI), and biochemical parameters (thyroid profile, vitamin D profile, iron profile, and blood indices) were measured.

RESULTS

In this study, serum vitamin D and iron levels were significantly (p<0.01) decreased in the hypothyroid female group (study group). The serum vitamin D and iron levels showed a significant negative (p<0.01) correlation with thyroid-stimulating hormone (TSH). Out of 250 study group participants, 61 had a concurrent deficiency of serum vitamin D and iron, yielding a probability (P of low vitamin D and iron and hypothyroidism) of 0.244, which indicates that if 1000 hypothyroid patients are tested for serum vitamin D and iron levels, 24 patients are probable to have low vitamin D and iron.

CONCLUSION

The study concluded that vitamin D and iron bi-deficiency were observed in adult hypothyroid females in Abu Dhabi, UAE. So, the routine check-up of thyroid function and vitamin D and iron profiles should be done early. Therefore, early vitamin D and iron deficiencies can be detected, and supplements can be given to prevent further health complications like osteoporosis and iron deficiency anemia.

The Role of Probiotics in Inducing and Maintaining Remission in Crohn's Disease and Ulcerative Colitis: A Systematic Review of the Literature

Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of the gastrointestinal tract affecting millions of patients worldwide. The gut microbiome partly determines the pathogenesis of both diseases. Even though probiotics have been widely used as a potential treatment, their efficacy in inducing and maintaining remission is still controversial. Our study aims to review the present-day literature about the possible role of probiotics in treating inflammatory bowel diseases in adults. This research was performed according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. We included studies concerning adult patients who compared probiotics with placebo or non-probiotic intervention. We identified thirty-three studies, including 2713 patients from fourteen countries. The role of probiotics in Crohn's disease was examined in eleven studies. Only four studies presented statistically significant results in the remission of disease, primarily when used for three to six months. On the other hand, in twenty-one out of twenty-five studies, probiotics proved effective in achieving or maintaining remission in ulcerative colitis. Supplementation with Bifidobacterium sp. or a combination of probiotics is the most effective intervention, especially when compared with a placebo. There is strong evidence supporting the usage of probiotic supplementation in patients with ulcerative colitis, yet more research is needed to justify their efficacy in Crohn's disease.

Vitamin D attenuates biofilm-associated infections via immunomodulation and cathelicidin expression: a narrative review

INTRODUCTION

Infections are becoming more difficult to treat, at least partly on account of microbes that produce biofilms. Reports suggest that decreased levels of antimicrobial peptides like cathelicidin, elevated levels of inflammatory cytokines, and biofilm formation are all associated with vitamin D deficiency, making vitamin D - deficient individuals more susceptible to infection. Infections attributable to biofilm-producing microbes can be managed by adjuvant therapy with vitamin D because of its immunomodulatory role, particularly because of the ability of vitamin D-pathway to induce the antimicrobial peptides like cathelicidin and decrease proinflammatory cytokines.

AREAS COVERED

This narrative review covers biofilm formation, infections associated with biofilm due to vitamin D deficiency, putative role of vitamin D in host protection and the effect of vitamin D supplementation in biofilm-associated infections. A comprehensive literature search in PubMed and Google Scholar utilizing suitable keywords at multiple time points extracted relevant articles.

EXPERT OPINION

Although vitamin D deficiency has been associated with infections by biofilm producing microbes, comprehensive clinical trials in various ethnicities are required to understand the likely relationships between vitamin D receptor gene expression, cathelicidin levels, and infection outcome. Current evidence hypothesizes that maintaining normal vitamin D level can help prevent and treat these infections.

Gut and genital tract microbiomes: Dysbiosis and link to gynecological disorders

Every year, millions of women are affected by genital tract disorders, such as bacterial vaginosis (BV), endometrial cancer, polycystic ovary syndrome (PCOS), endometriosis, and uterine fibroids (UFs). These disorders pose a significant economic burden on healthcare systems and have serious implications for health and fertility outcomes. This review explores the relationships between gut, vaginal, and uterine dysbiosis and the pathogenesis of various diseases of the female genital tract. In recent years, reproductive health clinicians and scientists have focused on the microbiome to investigate its role in the pathogenesis and prevention of such diseases. Recent studies of the gut, vaginal, and uterine microbiomes have identified patterns in bacterial composition and changes across individuals' lives associated with specific healthy and diseased states, particularly regarding the effects of the estrogen-gut microbiome axis on estrogen-driven disorders (such as endometrial cancer, endometriosis, and UFs) and disorders associated with estrogen deficiency (such as PCOS). Furthermore, this review discusses the contribution of vitamin D deficiency to gut dysbiosis and altered estrogen metabolism as well as how these changes play key roles in the pathogenesis of UFs. More research on the microbiome influences on reproductive health and fertility is vital.

Celiac Disease and Neurological Manifestations: From Gluten to Neuroinflammation

Celiac disease (CD) is a complex multi-organ disease with a high prevalence of extra-intestinal involvement, including neurological and psychiatric manifestations, such as cerebellar ataxia, peripheral neuropathy, epilepsy, headache, cognitive impairment, and depression. However, the mechanisms behind the neurological involvement in CD remain controversial. Recent evidence shows these can be related to gluten-mediated pathogenesis, including antibody cross-reaction, deposition of immune-complex, direct neurotoxicity, and in severe cases, vitamins or nutrients deficiency. Here, we have summarized new evidence related to gut microbiota and the so-called "gut-liver-brain axis" involved in CD-related neurological manifestations. Additionally, there has yet to be an agreement on whether serological or neurophysiological findings can effectively early diagnose and properly monitor CD-associated neurological involvement; notably, most of them can revert to normal with a rigorous gluten-free diet. Moving from a molecular level to a symptom-based approach, clinical, serological, and neurophysiology data might help to disentangle the many-faceted interactions between the gut and brain in CD. Eventually, the identification of multimodal biomarkers might help diagnose, monitor, and improve the quality of life of patients with "neuroCD".

Association between Suboptimal 25-Hydroxyvitamin D Status and Overweight/Obesity in Infants: A Prospective Cohort Study in China

This study aimed to investigate whether 25-hydroxyvitamin D (25(OH)D) concentrations are correlated to overweight/obesity in infants and to explore a threshold of 25(OH)D. A total of 1205 six-month-old infants from two community hospitals in Shanghai were randomly recruited, and 925 of them were followed up at 12 months. Concentration of 25(OH)D, weight, and length were measured at two time points. Overweight/obesity was defined as a weight-for-length Z-score >97th percentile. The prevalence of overweight/obesity at 6 and 12 months was 6.88% and 5.26%, respectively. The occurrence of vitamin D (VitD) deficiency (<20 ng/mL) at 6 and 12 months was 6.56% and 2.05%, respectively. Concentration of 25(OH)D at the corresponding age was negatively associated with weight-for-length percentile (WLP) at both 6 (adjusted β: −0.14; 95% CI: −0.27, −0.02; p = 0.02) and 12 months (adjusted β: −0.22; 95% CI: −0.41, −0.02; p = 0.03), while the relationship between 25(OH)D at 6 months and WLP at 12 months was nonlinear, where 35 ng/mL was identified as an inflection point. Those with a concentration of 25(OH)D <35 ng/mL at 6 months had a higher risk of overweight/obesity (adjusted OR: 1.42; 95% CI: 1.06, 1.91; p = 0.02) compared to the group with a concentration of 25(OH)D ≥35 ng/mL. Moreover, a concentration of 25(OH)D <35 ng/mL at two time points significantly increased the risk of overweight/obesity at 12 months compared to the group with 25(OH)D concentration ≥35 ng/mL at two time points (adjusted OR: 2.91; 95% CI: 1.13, 7.46; p = 0.03). A suboptimal 25(OH)D concentration <35 ng/mL significantly increases the risk of overweight/obesity in infants.

Association of sunshine duration with acute myocardial infarction hospital admissions in Beijing, China: A time-series analysis within-summer

BACKGROUND

Over the years, various epidemiological studies found that acute myocardial infarction (AMI) often shows seasonal rhythm patterning, which is usually influenced by the variations of environmental factors, such as air pollution, ambient temperature, solar activity, relative humidity. However, there are few studies on the impact of sunlight-induced AMI especially in developing countries, and they had inconsistent results. This study aimed to examine within-summer variations in the temporal association between sun exposure and AMI.

METHODS

We obtained hospitalization data for AMI of Beijing during 2013-2019. We used a distributed lag non-linear model (DLNM) combined with a quasi-Poisson regression model to estimate the non-linear lag effects of sunshine duration on AMI incidences. We evaluated the overall effect of AMI admissions with exposure to sunshine duration in the lag 0-21 days.

RESULTS

A total of 45,301 AMI cases were enrolled in our study during summer (June-September). The minimum of the morbidity was during days with a sunshine duration of 3.9 h. We found significant and U-shaped associations between sunshine duration and AMI, and the overall estimated relative risk was 1.29 (95% CI: 1.02,1.62) and 1.69 (95% CI: 1.28,2.24) for short (1st percentile) and long (99th percentile) sunshine duration, respectively. The males and younger people (<65 years) were most susceptible to these effects.

CONCLUSION

Our results suggest that both short and long sunshine duration could increase the risk of AMI admissions, especially for males and younger people. We suggest that public health policymakers should fully consider the balance of the pros and cons of solar exposure, and provide appropriate public health recommendations accordingly to gain the greatest benefits from sunlight.

Tipping the Balance: Vitamin D Inadequacy in Children Impacts the Major Gut Bacterial Phyla

Vitamin D inadequacy appears to be on the rise globally, and it has been linked to an increased risk of osteoporosis, as well as metabolic, cardiovascular, and autoimmune diseases. Vitamin D concentrations are partially determined by genetic factors. Specific single nucleotide polymorphisms (SNPs) in genes involved in vitamin D transport, metabolism, or binding have been found to be associated with its serum concentration, and these SNPs differ among ethnicities. Vitamin D has also been suggested to be a regulator of the gut microbiota and vitamin D deficiency as the possible cause of gut microbial dysbiosis and inflammation. This pilot study aims to fill the gap in our understanding of the prevalence, cause, and implications of vitamin D inadequacy in a pediatric population residing in Qatar. Blood and fecal samples were collected from healthy subjects aged 4–14 years. Blood was used to measure serum metabolite of vitamin D, 25-hydroxycholecalciferol 25(OH)D. To evaluate the composition of the gut microbiota, fecal samples were subjected to 16S rRNA gene sequencing. High levels of vitamin D deficiency/insufficiency were observed in our cohort with 97% of the subjects falling into the inadequate category (with serum 25(OH)D < 75 nmol/L). The CT genotype in rs12512631, an SNP in the GC gene, was associated with low serum levels of vitamin D (ANOVA, p = 0.0356) and was abundant in deficient compared to non-deficient subjects. Overall gut microbial community structure was significantly different between the deficient (D) and non-deficient (ND) groups (Bray Curtis dissimilarity p = 0.049), with deficient subjects also displaying reduced gut microbial diversity. Significant differences were observed among the two major gut phyla, Firmicutes (F) and Bacteroidetes (B), where deficient subjects displayed a higher B/F ratio (p = 0.0097) compared to ND. Vitamin D deficient children also demonstrated gut enterotypes dominated by the genus Prevotella as opposed to Bacteroides. Our findings suggest that pediatric vitamin D inadequacy significantly impacts the gut microbiota. We also highlight the importance of considering host genetics and baseline gut microbiome composition in interpreting the clinical outcomes related to vitamin D deficiency as well as designing better personalized strategies for therapeutic interventions.

Immunomodulatory Effects of Vitamin D Supplementation in a Deficient Population

In addition to its canonical functions, vitamin D has been proposed to be an important mediator of the immune system. Despite ample sunshine, vitamin D deficiency is prevalent (>80%) in the Middle East, resulting in a high rate of supplementation. However, the underlying molecular mechanisms of the specific regimen prescribed and the potential factors affecting an individual's response to vitamin D supplementation are not well characterized. Our objective is to describe the changes in the blood transcriptome and explore the potential mechanisms associated with vitamin D3 supplementation in one hundred vitamin D-deficient women who were given a weekly oral dose (50,000 IU) of vitamin D3 for three months. A high-throughput targeted PCR, composed of 264 genes representing the important blood transcriptomic fingerprints of health and disease states, was performed on pre and post-supplementation blood samples to profile the molecular response to vitamin D3. We identified 54 differentially expressed genes that were strongly modulated by vitamin D3 supplementation. Network analyses showed significant changes in the immune-related pathways such as TLR4/CD14 and IFN receptors, and catabolic processes related to NF-kB, which were subsequently confirmed by gene ontology enrichment analyses. We proposed a model for vitamin D3 response based on the expression changes of molecules involved in the receptor-mediated intra-cellular signaling pathways and the ensuing predicted effects on cytokine production. Overall, vitamin D3 has a strong effect on the immune system, G-coupled protein receptor signaling, and the ubiquitin system. We highlighted the major molecular changes and biological processes induced by vitamin D3, which will help to further investigate the effectiveness of vitamin D3 supplementation among individuals in the Middle East as well as other regions.

Major histocompatibility complex (MHC) associations with diseases in ethnic groups of the Arabian Peninsula

Since the discovery of human leukocyte antigens (HLAs), the function of major histocompatibility complex (MHC) gene families in a wide range of diseases have been the subject of research for decades. In particular, the associations of autoimmune disorders to allelic variants and candidate genes encoding the MHC are well documented. However, despite decades of research, the knowledge of MHC associations with human disease susceptibility have been predominantly studied in European origin, with limited understanding in different populations and ethnic groups. This is particularly evident in countries and ethnic populations of the Arabian Peninsula. Human MHC haplotypes, and its association with diseases, of the variable ethnic groups of this region are poorly studied. This review compiled published manuscripts that have reported a list of autoimmune diseases (insulin-dependent diabetes mellitus, systemic lupus erythematosus, myasthenia gravis, rheumatoid arthritis, psoriasis vulgaris, and multiple sclerosis) associated with MHC class I and class II in the populations of the Arabian Peninsula, specifically Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, the United Arab Emirates, and Yemen. Data available was compared with other three ethnic groups, namely Caucasians, Asians, and Africans. The limited data available in the public domain on the association between MHC gene and autoimmune diseases highlight the challenges in the Middle Eastern region.

Vaginal Microbiota and Cytokine Levels Predict Preterm Delivery in Asian Women

Preterm birth (PTB) is the most common cause of neonatal morbidity and mortality worldwide. Approximately half of PTBs is linked with microbial etiologies, including pathologic changes to the vaginal microbiota, which vary according to ethnicity. Globally more than 50% of PTBs occur in Asia, but studies of the vaginal microbiome and its association with pregnancy outcomes in Asian women are lacking. This study aimed to longitudinally analyzed the vaginal microbiome and cytokine environment of 18 Karen and Burman pregnant women who delivered preterm and 36 matched controls delivering at full term. Using 16S ribosomal RNA gene sequencing we identified a predictive vaginal microbiota signature for PTB that was detectable as early as the first trimester of pregnancy, characterized by higher levels of Prevotella buccalis, and lower levels of Lactobacillus crispatus and Finegoldia, accompanied by decreased levels of cytokines including IFNγ, IL-4, and TNFα. Differences in the vaginal microbial diversity and local vaginal immune environment were associated with greater risk of preterm birth. Our findings highlight new opportunities to predict PTB in Asian women in low-resource settings who are at highest risk of adverse outcomes from unexpected PTB, as well as in Burman/Karen ethnic minority groups in high-resource regions.

The interplay between gut microbiota and autism spectrum disorders: A focus on immunological pathways

Autism spectrum disorders (ASD) are a group of neurodevelopmental disorders characterized by impairments in social and cognitive activities, stereotypical and repetitive behaviors and restricted areas of interest. A remarkable proportion of ASD patients represent immune dysregulation as well as gastrointestinal complications. Hence, a novel concept has recently emerged, addressing the possible intercommunication between the brain, the immune system, the gut and its commensals. Here, we provide an overview of how gut microbes and their metabolites are associated with neurobehavioral features of ASD through various immunologic mechanisms. Moreover, we discuss the potential therapeutic options that could modify these features.

Distinctive Microbial Signatures and Gut-Brain Crosstalk in Pediatric Patients with Coeliac Disease and Type 1 Diabetes Mellitus

Coeliac disease (CD) and Type 1 diabetes mellitus (T1DM) are immune-mediated diseases. Emerging evidence suggests that dysbiosis in the gut microbiome plays a role in the pathogenesis of both diseases and may also be associated with the development of neuropathy. The primary goal in this cross-sectional pilot study was to identify whether there are distinct gut microbiota alterations in children with CD (n = 19), T1DM (n = 18) and both CD and T1DM (n = 9) compared to healthy controls (n = 12). Our second goal was to explore the relationship between neuropathy (corneal nerve fiber damage) and the gut microbiome composition. Microbiota composition was determined by 16S rRNA gene sequencing. Corneal confocal microscopy was used to determine nerve fiber damage. There was a significant difference in the overall microbial diversity between the four groups with healthy controls having a greater microbial diversity as compared to the patients. The abundance of pathogenic proteobacteria Shigella and E. coli were significantly higher in CD patients. Differential abundance analysis showed that several bacterial amplicon sequence variants (ASVs) distinguished CD from T1DM. The tissue transglutaminase antibody correlated significantly with a decrease in gut microbial diversity. Furthermore, the Bacteroidetes phylum, specifically the genus Parabacteroides was significantly correlated with corneal nerve fiber loss in the subjects with neuropathic damage belonging to the diseased groups. We conclude that disease-specific gut microbial features traceable down to the ASV level distinguish children with CD from T1DM and specific gut microbial signatures may be associated with small fiber neuropathy. Further research on the mechanisms linking altered microbial diversity with neuropathy are warranted.

Lower Level of Plasma 25-Hydroxyvitamin D in Children at Diagnosis of Celiac Disease Compared with Healthy Subjects: A Case-Control Study

OBJECTIVE

To evaluate the vitamin D status of children with a new diagnosis of celiac disease compared with healthy controls.

STUDY DESIGN

This was a case-control study. Cases were consecutive children with newly diagnosed celiac disease. Controls were healthy children matched for age, sex, ethnicity, and month of blood testing. Plasma 25-hydroxyvitamin D (25-OHD) was measured as the index of vitamin D nutritional status. The Student t test was used for comparisons. Differences in frequencies were evaluated with the χ² test. Associations between variables were estimated by calculating Pearson correlation coefficients.

RESULTS

There were 131 children with celiac disease enrolled (62% females; mean age 8.1 ± 1.1 years). The control group included 131 healthy children (62% females; mean age 8.2 ± 1.2). All were of European origin. Plasma 25-OHD levels were significantly lower in patients than in controls (25.3 ± 8.0 and 31.6 ± 13.7 ng/mL; P < .0001). The percentage of children with vitamin D deficiency (<20 ng/mL) was significantly higher in children with celiac diseaseas compared with controls (31% vs 12%; P < .0001). The concentration of 25-OHD was significantly lower in patients than in controls during summer (P < .01) and autumn (P < .0001).

CONCLUSIONS

In this case-control study, at diagnosis, children with celiac disease showed lower levels of plasma 25-OHD compared with healthy subjects. Vitamin D status should be checked at diagnosis of celiac disease, particularly during summer and fall months.

Perspective of Immunopathogenesis and Immunotherapies for Kawasaki Disease

Kawasaki Disease (KD) is an acute inflammatory illness that mostly occurs in children below 5 years of age, with intractable fever, mucocutaneous lesions, lymphadenopathy, and lesions of the coronary artery (CAL). KD is sharing clinical symptoms with systemic inflammatory syndrome in children (MIS-C) which is related to COVID-19. Certain genes are identified to be associated with KD, but the findings usually differ between countries and races. Human Leukocyte Antigen (HLA) allele types and toll-like receptor (TLR) expression are also correlated to KD. The acute hyperinflammation in KD is mediated by an imbalance between augmented T helper 17 (Th17)/Th1 responses with high levels of interleukin (IL)-6, IL-10, IL-17A, IFN-γ, and IP-10, in contrast to reduced Th2/Treg responses with lower IL-4, IL-5, FoxP3, and TGF-β expression. KD has varying phenotypic variations regarding age, gender, intravenous immunoglobulin (IVIG) resistance, macrophage activation and shock syndrome. The signs of macrophage activation syndrome (MAS) can be interpreted as hyperferritinemia and thrombocytopenia contradictory to thrombocytosis in typical KD; the signs of KD with shock syndrome (KDSS) can be interpreted as overproduction of nitric oxide (NO) and coagulopathy. For over five decades, IVIG and aspirin are the standard treatment for KD. However, some KD patients are refractory to IVIG required additional medications against inflammation. Further studies are proposed to delineate the immunopathogenesis of IVIG-resistance and KDSS, to identify high risk patients with genetic susceptibility, and to develop an ideal treatment regimen, such as by providing idiotypic immunoglobulins to curb cytokine storms, NO overproduction, and the epigenetic induction of Treg function.

The potential role of vitamin D supplementation as a gut microbiota modifier in healthy individuals

Vitamin D deficiency affects approximately 80% of individuals in some countries and has been linked with gut dysbiosis and inflammation. While the benefits of vitamin D supplementation on the gut microbiota have been studied in patients with chronic diseases, its effects on the microbiota of otherwise healthy individuals is unclear. Moreover, whether effects on the microbiota can explain some of the marked inter-individual variation in responsiveness to vitamin D supplementation is unknown. Here, we administered vitamin D to 80 otherwise healthy vitamin D-deficient women, measuring serum 25(OH) D levels in blood and characterizing their gut microbiota pre- and post- supplementation using 16S rRNA gene sequencing. Vitamin D supplementation significantly increased gut microbial diversity. Specifically, the Bacteroidetes to Firmicutes ratio increased, along with the abundance of the health-promoting probiotic taxa Akkermansia and Bifidobacterium. Significant variations in the two-dominant genera, Bacteroides and Prevotella, indicated a variation in enterotypes following supplementation. Comparing supplementation responders and non-responders we found more pronounced changes in abundance of major phyla in responders, and a significant decrease in Bacteroides acidifaciens in non-responders. Altogether, our study highlights the positive impact of vitamin D supplementation on the gut microbiota and the potential for the microbial gut signature to affect vitamin D response.

Role of the gut microbiota in the pathogenesis of coeliac disease and potential therapeutic implications

PURPOSE

Although genetic predisposition and exposure to dietary gluten are considered necessary triggers for the development of coeliac disease, alterations in the gut microbial composition may also contribute towards the pathogenesis of coeliac disease. This review aims to provide an overview of the available data on the potential mechanisms through which the gut microbiota plays a role in the causation of coeliac disease and to discuss the potential therapeutic strategies that could diminish the consequences of microbial dysbiosis.

METHOD

A search of the literature was performed using the PubMed, Embase, and JSTOR databases; relevant articles were included.

RESULTS

Recent studies in patients with coeliac disease have reported an increase in the relative amounts of gram negative bacterial genera such as Bacteroides, Prevotella, and Escherichia, and reduced amounts of protective anti-inflammatory bacteria such as Bifidobacteria and Lactobacilli. Dysbiotic microbiota may lead to a dysregulated immune response that may contribute to the pathogenesis of coeliac disease. In infancy, antibiotic use and certain infant feeding practices may lead to alterations in the developing gut microbiota to influence the immune maturation process and predispose to coeliac disease.

CONCLUSION

The induction of the intestinal immune system and gluten intolerance may be influenced by the relative abundance of certain microbiota. Factors such as infant feeding practices, diet, antibiotics, and infections, may be involved in the development of coeliac disease due to their influence on gut microbial composition. The efficacy of potential modulators of the gut microbiota such as probiotics, prebiotics, and fecal microbial transplant as adjunctive treatments to gluten-free diet in coeliac disease is unproven and requires further investigation.

Vitamin D in obesity and obesity-related diseases: an overview

Hypovitaminosis D and obesity represent two pandemic conditions sometimes associated with each other. Although it is known that there is a close relationship between these two health problems, the underlying pathophysiological mechanism has not yet been fully clarified. In fact, on the one hand, obesity per se seems to involve low circulating levels of vitamin D due to low sun exposure, physical activity, and intake of foods rich in vitamin D, volumetric dilution and sequestration in the adipose tissue. Conversely, since preadipocytes and adipocytes express the receptors and are involved in the metabolism of vitamin D it would seem that low levels of this vitamin may be involved in adipogenesis and therefore in the development of obesity. This connection is extremely important when considering obesity-related diseases. In fact, low vitamin D levels and severe obesity are significantly associated with some cardio-metabolic risk factors, including high Body Mass Index, waist circumference, blood pressure, impaired lipid and glycemic profile and insulin resistance, as they would seem associated with worse cardiovascular outcomes and higher cancer incidence and mortality. Therefore, the purpose of this review was to examine the recent evidence linking low vitamin D status, obesity and obesity-related diseases, highlighting the scientific achievements and the gaps to be filled with further investigations.

The Role of Polymorphisms in Vitamin D-Related Genes in Response to Vitamin D Supplementation

Background. Vitamin D deficiency represents a major healthcare problem. Vitamin D status is influenced by genetic and environmental determinants. Several observational studies have evaluated the association of single-nucleotide polymorphisms (SNPs) in vitamin D-related genes and vitamin D levels. Nevertheless, little is known about the role of these SNPs in the response to vitamin D supplementation. We conducted an interventional study to define the association between SNPs in vitamin D-related genes and the response to vitamin D supplementation in 100 self-reported healthy women of Arab ancestry for the majority. Methods. A total of 100 healthy female subjects received a weekly oral dose of 50,000 IU vitamin D for 12 weeks. Serum vitamin D concentration and metabolic profiles were measured at baseline and 12 weeks post-vitamin D supplementation. The genotypes of 37 SNPs selected from previously reported vitamin D-related genes have been assessed by Fluidigm genotyping assay. Results. Rs731236 (VDR gene) and rs7116978 (CYP2R1 gene) showed a significant association with vitamin D status. The rs731236 GG genotype and the rs7116978 CC genotype were associated with a “vitamin D sufficiency” state. Rs731236 GG and rs7116978 CC genotypes showed a higher response to vitamin D supplementation. Transcription factor binding site prediction analysis showed altered binding sites for transcription factors according to the different rs7116978 alleles. Interestingly, the 37 SNPs previously established to play a role in vitamin D-related pathways explained very little of the response to vitamin D supplementation in our cohort, suggesting the existence of alternative loci whose number and effect size need to be investigated in future studies. Conclusion. In this paper, we present novel data on vitamin D-related SNPs and response to vitamin D supplementation demonstrating the feasibility of applying functional genomic approaches in interventional studies to assess individual-level responses to vitamin D supplementation.

Diagnosis and management of osteoporosis in postmenopausal women in Gulf Cooperation Council (GCC) countries: consensus statement of the GCC countries' osteoporosis societies under the auspices of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO)

A consensus platform is provided by the experts of the Gulf Cooperation Council (GCC) countries' respective osteoporosis societies, on which specific guidelines can be developed further for regional use on the assessment and treatment of postmenopausal women at risk from fractures due to osteoporosis.

INTRODUCTION

Guidance is provided in a Gulf Cooperation Council (GCC) country setting on the assessment and treatment of postmenopausal women at risk from fractures due to osteoporosis, which is an adaptation of the European guidance by Kanis et al., jointly published by the International Osteoporosis Foundation and the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis (ESCEO). The respective osteoporosis societies of the Gulf Cooperation Council (GCC) countries assembled for a unifying consensus on the diagnosis and management of osteoporosis in postmenopausal women for the region.

METHODS

The Chair for Biomarkers of Chronic Diseases (CBCD) in King Saud University (KSU), Riyadh, Kingdom of Saudi Arabia (KSA), in cooperation with the Saudi Osteoporosis Society (SOS), hosted regional experts and respective leaders from different GCC osteoporosis societies, together with an adviser from the ESCEO. An assembly of experts representing the different osteoporosis societies from Saudi Arabia, the UAE, Bahrain, Oman, and Kuwait gathered on February 15-16, 2019 in Riyadh, KSA for the formulation of a general osteoporosis consensus for the region.

RESULTS

The following areas were covered: diagnosis of osteoporosis and assessment of fracture risk; general and pharmacological management of osteoporosis; and hip fractures, vitamin D, recommendation on which FRAX tool to follow, and the importance of country-specific FRAX® and fracture liaison services for secondary fracture prevention.

CONCLUSIONS

A platform is provided on which specific guidelines can be developed for regional use in GCC.

Calcitriol Regulates the Differentiation of IL-9-Secreting Th9 Cells by Modulating the Transcription Factor PU.1

Vitamin D can modulate the innate and adaptive immune system. Vitamin D deficiency has been associated with various autoimmune diseases. Th9 cells are implicated in the pathogenesis of numerous autoimmune diseases. Thus, we investigated the role of calcitriol (active metabolite of vitamin D) in the regulation of Th9 cell differentiation. In this study, we have unraveled the molecular mechanisms of calcitriol-mediated regulation of Th9 cell differentiation. Calcitriol significantly diminished IL-9 secretion from murine Th9 cells associated with downregulated expression of the Th9-associated transcription factor, PU.1. Ectopic expression of VDR in Th9 cells attenuated the percentage of IL-9-secreting cells. VDR associated with PU.1 in Th9 cells. Using a series of mutations, we were able to dissect the VDR domain involved in the regulation of the Il9 gene. The VDR-PU.1 interaction prevented the accessibility of PU.1 to the Il9 gene promoter, thereby restricting its expression. However, the expression of Foxp3, regulatory T cell-specific transcription factor, was enhanced in the presence of calcitriol in Th9 cells. When Th9 cells are treated with both calcitriol and trichostatin A (histone deacetylase inhibitor), the level of IL-9 reached to the level of wild-type untreated Th9 cells. Calcitriol attenuated specific histone acetylation at the Il9 gene. In contrast, calcitriol enhanced the recruitment of the histone modifier HDAC1 at the Il9 gene promoter. In summary, we have identified that calcitriol blocked the access of PU.1 to the Il9 gene by reducing its expression and associating with it as well as regulated the chromatin of the Il9 gene to regulate expression.

Vitamin D, gut microbiota, and radiation-related resistance: a love-hate triangle

Radiation resistance is a serious issue in radiotherapy. Increasing evidence indicates that the human gut microbiome plays a role in the development of radiation resistance. Vitamin D is an important supplement for cancer patients treated with radiotherapy. Against this background, this paper reviewed research regarding the associations among vitamin D, microbiota dysbiosis, and radiation resistance. A hypothesis is developed to describe the relationships among vitamin D, the gut microbiota, and radiotherapy outcomes. Radiotherapy changes the composition of the gut microbiota, which in turn influence the serum level of vitamin D, and its distribution and metabolism in the body. Alteration of vitamin D level influences the patient response to radiotherapy, where the underlying mechanisms may be associated with the intestinal microenvironment, immune molecules in the intestines, gut microbiome metabolites, and signaling pathways associated with vitamin D receptors. Our understanding of the contribution of vitamin D and the gut microbiota to radiotherapy outcomes has been increasing gradually. A better understanding of the relationships among vitamin D, the gut microbiota, and radiotherapy outcomes will shed more light on radiation resistance, and also promote the development of new strategies for overcoming it, thus addressing an important challenge associated with the currently available radiotherapy modalities for cancer patients.

Integrating omics for a better understanding of Inflammatory Bowel Disease: a step towards personalized medicine

Background

Inflammatory Bowel Disease (IBD) is a multifactorial chronic disease. Understanding only one aspect of IBD pathogenesis does not reflect the complex nature of IBD nor will it improve its clinical management. Therefore, it is vital to dissect the interactions between the different players in IBD pathogenesis in order to understand the biology of the disease and enhance its clinical outcomes.

Aims

To provide an overview of the available omics data used to assess the potential mechanisms through which various players are contributing to IBD pathogenesis and propose a precision medicine model to fill the current knowledge gap in IBD.

Results

Several studies have reported microbial dysbiosis, immune and metabolic dysregulation in IBD patients, however, this data is not sufficient to create signatures that can differentiate between the disease subtypes or between disease relapse and remission.

Conclusions

We summarized the current knowledge in the application of omics in IBD patients, and we showed that the current knowledge gap in IBD hinders the improvements of clinical decision for treatment as well as the prediction of disease relapse. We propose one way to fill this gap by implementing integrative analysis of various omics datasets generated from one patient at a single time point.

Hair regrowth following fecal microbiota transplantation in an elderly patient with alopecia areata: A case report and review of the literature

BACKGROUND

Alopecia areata is a hair loss disease associated with genetics, autoimmunity, and other factors. There is an intriguing link between alopecia areata and gut dysbiosis. Fecal microbiota transplantation (FMT) has been recommended to treat Clostridium difficile (previously known as Clostridioides difficile) infection, and has also shown potentials in the treatment of inflammatory bowel disease, irritable bowel syndrome, and non-alcohol fatty liver disease.

CASE SUMMARY

An 86-year-old man, with a history of sigmoid colon carcinoma, suffered from recurrent abdominal pain and distension, and diarrhea for six months, with inappetence. At admission, he was also diagnosed with depression. Upon physical examination, the patient presented with a 1.5 cm × 2.0 cm alopecia areata on his right occiput. Due to the negative results of laboratory testing, capsule endoscopy, and colonoscopy, the patient was diagnosed with noninfectious diarrhea, depressive disorder, and patchy alopecia areata. Considering that noninfectious diarrhea in the elderly patient was mainly caused by gut dysbiosis, he was given six rounds of FMT. His diarrhea improved remarkably one month after FMT, with improved appetite and disappearance of abdominal pain, distension, and depressive symptoms. Surprisingly, he reported new hair growth on the affected region of his scalp, with some of his white hair gradually turning to black, without taking any other therapies for alopecia areata before and after FMT.

CONCLUSION

FMT might act as a potential therapy for patients who suffer from alopecia areata. Large and well-designed studies are required to confirm the role of FMT in alopecia areata.