Calcium and 1 alpha,25-dihydroxyvitamin D3 target the TNF-alpha pathway to suppress experimental inflammatory bowel disease

Systemic Anti-Inflammatory Agents in the Prevention of Chemoradiation-Induced Mucositis: A Review of Randomised Controlled Trials

Mucositis is a pathological condition characterised by inflammation and ulceration of the mucous membranes lining the alimentary canal, particularly in the mouth (oral mucositis) and the gastrointestinal tract. It is a common side effect of cancer treatments, including chemotherapy and radiotherapy, and it is sometimes responsible for treatment interruptions. Preventing mucositis throughout the alimentary tract is therefore crucial. However, current interventions mainly target either oral or gastrointestinal side effects. This review aimed to investigate the use of systemically administered anti-inflammatory agents to prevent mucositis in cancer patients undergoing cancer treatment. PubMed, Ovid, Scopus, Web of Science, WHO ICTRP and ClinicalTrials.gov were screened to identify eligible randomised controlled trials (RCTs). The published literature on anti-inflammatory agents provides mixed evidence regarding the degree of efficacy in preventing/reducing the severity of mucositis in most anticancer treatments; however, sample size continued to be a significant limitation, alongside others discussed. Our review yielded a list of several anti-inflammatory agents that exhibit potential mucositis-preventive effects in cancer patients undergoing cancer treatment, which can be used to inform clinical practice.

Dietary supplementation of vitamin D3 and calcium partially recover the compromised time budget and circadian rhythm of lying behavior in lactating cows under heat stress

Heat stress (HS) impedes cattle behavior and performance and is an animal comfort and welfare issue. The objective of this study was to characterize the time budget and circadian rhythm of lying behavior in dairy cows during HS and to assess the effect of dietary supplementation of vitamin D3 and Ca. Twelve multiparous Holstein cows (42.2 ± 5.6 kg milk/d; 83 ± 27 d in milk) housed in tiestalls were used in a split-plot design with the concentration of dietary vitamin E and Se as main plots (LESe: 11.1 IU/kg and 0.55 mg/kg, and HESe: 223 IU/kg and 1.8 mg/kg, respectively). Within each plot cows were randomly assigned to (1) HS with low concentrations of vitamin D3 and Ca (HS, 1,012 IU/kg and 0.73%, respectively), (2) HS with high concentrations of vitamin D3 and Ca (HS+D3/Ca; 3,764 IU/kg and 0.97%, respectively), or (3) thermoneutral pair-fed (TNPF) with low concentrations of vitamin D3 and Ca (1,012 IU/kg and 0.73%, respectively) in a Latin square design with 14-d periods and 7-d washouts. Lying behavior was measured with HOBO Loggers in 15-min intervals. Overall, cows in HS spent less time lying per day relative to TNPF from d 7 to 14. Daily lying time was positively correlated with milk yield, energy-corrected milk yield, and feed efficiency, and was negatively correlated with rectal temperature, respiratory rate, fecal calprotectin, tumor necrosis factor-α, and C-reactive protein. A treatment by time interaction was observed for lying behavior: the time spent lying was lesser for cows in HS than in TNPF in the early morning (0000-0600 h) and in the night (1800-2400 h). The circadian rhythm of lying behavior was characterized by fitting a cosine function of time into linear mixed model. Daily rhythmicity of lying was detected for cows in TNPF and HS+D3/Ca, whereas only a tendency in HS cows was observed. Cows in TNPF had the highest mesor (the average level of diurnal fluctuations; 34.2 min/h) and amplitude (the distance between the peak and mesor; 17.9 min/h). Both the mesor and amplitude were higher in HS+D3/Ca relative to HS (26.6 vs. 25.2 min/h and 3.91 min/h vs. 2.18 min/h, respectively). The acrophase (time of the peak) of lying time in TNPF, HS, and HS+D3/Ca were 0028, 0152, and 0054 h, respectively. Lastly, a continuous increase in daily lying time in TNPF was observed during the first 4 d of the experimental period in which DMI was gradually restricted, suggesting that intake restrictions may shift feeding behavior and introduce biases in the behavior of animals. In conclusion, lying behavior was compromised in dairy cows under HS, characterizing reduced daily lying time and disrupted circadian rhythms, and the compromised lying behavior can be partially restored by supplementation of vitamin D3 and Ca. Further research may be required for a more suitable model to study behavior of cows under HS.

Delineating the role of nuclear receptors in colorectal cancer, a focused review

Colorectal cancer (CRC) stands as one of the most prevalent form of cancer globally, causing a significant number of deaths, surpassing 0.9 million in the year 2020. According to GLOBOCAN 2020, CRC ranks third in incidence and second in mortality in both males and females. Despite extensive studies over the years, there is still a need to establish novel therapeutic targets to enhance the patients' survival rate in CRC. Nuclear receptors (NRs) are ligand-activated transcription factors (TFs) that regulate numerous essential biological processes such as differentiation, development, physiology, reproduction, and cellular metabolism. Dysregulation and anomalous expression of different NRs has led to multiple alterations, such as impaired signaling cascades, mutations, and epigenetic changes, leading to various diseases, including cancer. It has been observed that differential expression of various NRs might lead to the initiation and progression of CRC, and are correlated with poor survival outcomes in CRC patients. Despite numerous studies on the mechanism and role of NRs in this cancer, it remains of significant scientific interest primarily due to the diverse functions that various NRs exhibit in regulating key hallmarks of this cancer. Thus, modulating the expression of NRs with their agonists and antagonists, based on their expression levels, holds an immense prospect in the diagnosis, prognosis, and therapeutical modalities of CRC. In this review, we primarily focus on the role and mechanism of NRs in the pathogenesis of CRC and emphasized the significance of targeting these NRs using a variety of agents, which may represent a novel and effective strategy for the prevention and treatment of this cancer.

Consumption of dairy products and odds of ulcerative colitis: An Iranian case-control study

The association between dairy product consumption and the risk of ulcerative colitis (UC) is not well elucidated. This case-control study examined the association between Iranian adults' dairy consumption and UC risk. We used a valid food frequency questionnaire to analyze dietary intakes in 340 patients with pathologically confirmed cases of UC and 782 controls as part of a case-control research. Pasteurized milk, cheese, and yogurt dietary intakes were calculated along with dairy products. Other variables were acquired using questionnaires. Study participants' mean (± SD) age and body mass index were 41.5 ± 14.1 years and 27.4 ± 4.77 kg/m2, respectively. After adjusting for potential variables, individuals who consumed more total dairy products were less likely to get UC than those who consumed less (odds ratio [OR]: 0.44; 95% confidence interval (CI): 0.24, 0.79). We found a significant reverse association between milk intake (OR: 0.13; 95% CI: 0.07-0.24) and yogurt intake (OR: 0.52; 95% CI: 0.29-0.91) and UC, after controlling for potential confounders. Also, no significant association was found between cheese and UC risk (OR: 1.38; 95% CI: 0.84-2.28). Higher consumption of total dairy products may reduce UC risk. To be specific, milk and yogurt are inversely associated with this disorder. However, no link was found between cheese intake and UC. Longitudinal observational studies, especially cohorts, are needed to further assess these associations.

Plasma and milk metabolomics revealed changes in amino acid metabolism in Holstein dairy cows under heat stress

Our understanding of metabolic alterations triggered by heat stress is incomplete, which limits the designing of nutritional strategies to mitigate negative productive and health effects. Thus, this study aimed to explore the metabolic responses of heat-stressed dairy cows to dietary supplementation with vitamin D3/Ca and vitamin E/Se. Twelve multiparous Holstein cows were enrolled in a split-plot Latin square design with two distinct vitamin E/Se supplementation levels, either at a low (ESe-, n = 6, 11.1 IU/kg vitamin E and 0.55 mg/kg Se) or a high dose (ESe+, n = 6 223 IU/kg vitamin E and 1.8 mg/kg Se) as the main plot. Treatment subplots, arranged in a replicated 3 × 3 Latin square design, comprised heat challenge (Temperature Humidity Index, THI: 72.0-82.0) supplemented with different levels of vitamin D3/Ca: either low (HS/DCa-, 1 012 IU/kg and 0.73%, respectively) or high (HS/DCa+, 3 764 IU/kg and 0.97%, respectively), and a pair-fed control group in thermoneutrality (THI = 61.0-64.0) receiving the low dose of vitamin D3/Ca (TN). The liquid chromatography-mass spectrometry-based metabolome profile was determined in blood plasma and milk sampled at the beginning (day 0) and end (day 14) of each experimental period. The results were analyzed for the effect of (1) TN vs. HS/ESe-/DCa-, and (2) the vitamin E/Se and vitamin D3/Ca supplementation. No group or group × day effects were detected in the plasma metabolome (false discovery rate, FDR > 0.05), except for triglyceride 52:2 being higher (FDR = 0.03) on day 0 than 14. Taurine, creatinine and butyryl-carnitine showed group × day interactions in the milk metabolome (FDR ≤ 0.05) as creatinine (+22%) and butyryl-carnitine (+190%) were increased (P < 0.01) on day 14, and taurine was decreased (-65%, P < 0.01) on day 14 in the heat stress (HS) cows, compared with day 0. Most compounds were unaffected by vitamin E/Se or vitamin D3/Ca supplementation level or their interaction (FDR > 0.05) in plasma and milk, except for milk alanine which was lower (-69%, FDR = 0.03) in the E/Se+ groups, compared with E/Se-. Our results indicated that HS triggered more prominent changes in the milk than in the plasma metabolome, with consistent results in milk suggesting increased muscle catabolism, as reflected by increased creatinine, alanine and citrulline levels. Supplementing with high levels of vitamin E/Se or vitamin D3/Ca or their combination did not appear to affect the metabolic remodeling triggered by HS.

The Effect of Vitamin D Consumption on Pro-Inflammatory Cytokines in Athletes: A Systematic Review of Randomized Controlled Trials

Vitamin D is essential for the optimal health of the skeletal system. However, this vitamin also plays a role in other functions of the human body, such as muscle, immune, and inflammatory functions. Some studies have reported that adequate levels of vitamin D improve immune system function by reducing the levels of certain pro-inflammatory cytokines, which can protect against the risk of post-exercise illness. This systematic review aims to investigate the effects of vitamin D supplementation on pro-inflammatory cytokines in athletes. This study was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A literature search was conducted in SPORTDiscus, PubMed, ScienceDirect, and Google Scholar up to 1 October 2023. The quality of the articles was evaluated using the Risk of Bias 2 Tool. After searching the databases, a total of 7417 studies were identified, 6 of which met the eligibility criteria, and their outcomes were presented. The six studies included 176 participants. All six studies are randomized control trials, including a total of 176 subjects, primarily men (81%). Regarding the types of athletes, most participants were endurance athletes. Our investigation in this systematic review demonstrated that out of the six studies, only two of them reported significant changes in IL-6 and TNF-α levels after taking high-dose vitamin D. Other studies did not present any significant changes after vitamin D supplementation in athletes with respect to IL-6 and TNF-α levels. Further studies are needed to determine the effectiveness of vitamin D supplementation for athletes as a disease-prone community.

Shining a Light on Selenium: a Meta-analysis of Supplementation in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic immune-mediated demyelinating disease of the central nervous system. Selenium is a trace element with significant antioxidant activity. This study aimed to seek evidence concerning selenium supplementation in MS. A systematic search was performed on PubMed, Web of Science, Scopus, and Embase databases to identify the studies assessing the consumption rate, efficacy, and safety of selenium and selenium-containing supplementations in MS patients. The meta-analysis was performed using the Comprehensive Meta-Analysis and the risk of bias was evaluated using the Joanna Briggs Institute's critical appraisal tools. A total of 9 studies were included, which consisted of six studies regarding the rate of selenium supplement consumption in MS patients, with a total sample size of 2381 patients. Based on the quantitative synthesis, 14.3% (95% CI, 12.8-16.0%; I2, 3.58%) of MS patients had current selenium supplements usage, and 11.3% (95% CI, 7.6-16.6%; I2, 81.40%) of patients had used selenium supplements previously. Although there is no evidence regarding supplementation with selenium alone, three RCT studies reported the safety of selenium-containing supplementation use in MS with improved inflammation and oxidative stress conditions. The findings of this study show that over 10% of patients with MS used selenium supplements, with no clinical significance supporting the benefits. There is a lack of evidence regarding the safety and efficacy of selenium supplements in MS patients. Due to the limited number of included studies and the lack of comprehensive and specific studies regarding selenium supplements in MS, the results must be interpreted with caution, and future clinical trials are required.

Risk Factors and Cellular Differences in Heart Failure: The Key Role of Sex Hormones

Patients with heart failure are conventionally stratified into phenotypic groups based on their ejection fraction. The aim of this stratification is to improve disease management with a more targeted therapeutic approach. A further subdivision based on patient gender is justified. It is recognized that women are underrepresented in randomized controlled clinical trials, resulting in limited clinical and molecular differentiation between males and females. However, many observational studies show that the onset, development, and clinical course of the disease may substantially differ between the two sexes. According to the emerging concept of precision medicine, investigators should further explore the mechanisms responsible for the onset of heart failure due to sex differences. Indeed, the synergistic or opposing effects of sex hormones on the cardiovascular system and underlying heart failure mechanisms have not yet been clarified. Sex hormones, risk factors impact, and cardiovascular adaptations may be relevant for a better understanding of the intrinsic pathophysiological mechanisms in the two sexes. Despite the differences, treatment for HF is similar across the whole population, regardless of sex and gender. In our review, we describe the main differences in terms of cardiovascular dysfunction, risk factors, and cellular signaling modifications related to the hormonal pattern.

The effects and predictive value of calcium and magnesium concentrations on nutritional improvement, inflammatory response and diagnosis in patients with Crohn's disease

BACKGROUND

Crohn's disease (CD) is a progressive inflammatory disease of the gastrointestinal tract associated with malnutrition, high levels of inflammation and calcium and magnesium deficiencies. However, the relationships between these symptoms are poorly defined.

METHOD

Seventy-six adult CD patients who had not yet started treatment and 83 healthy volunteers were recruited. The dietary intakes, serum calcium and magnesium levels, nutritional indicators and biochemical markers of disease activity were measured.

RESULTS

Most participants had inadequate magnesium and calcium intake. The serum magnesium and calcium levels, as well as nutritional and inflammatory indicators, differed significantly between CD patients and controls, especially in the active phase. Serum levels of magnesium and calcium correlated with both nutritional status and inflammation. The cut-off values for CD development were 0.835 mmol/L (magnesium) and 2.315 mmol/L (calcium), whereas those for the active phase were 0.785 and 2.28 mmol/L, respectively.

CONCLUSION

Adequate intake of magnesium and calcium may both improve the nutritional status of CD patients and reduce inflammation, benefiting disease relief. As both magnesium and calcium reflect CD status, they may be useful markers for CD diagnosis and disease activity.

Role of micronutrients in inflammatory bowel disease

Inflammatory bowel disease (IBD) is an autoimmune intestinal disease that includes ulcerative colitis, Crohn's disease, and indeterminate colitis. Patients with IBD are often at risk for malnutrition, including micronutrient deficiencies, due to dietary restrictions and poor intestinal absorption. Micronutrients, including vitamins and minerals, play an important role in the human body's metabolism and maintenance of tissue functions. This article reviews the role of micronutrients in IBD. Micronutrients can affect the occurrence and progression of IBD by regulating immunity, intestinal flora, oxidative stress, intestinal barrier function, and other aspects. Monitoring and timely supplementation of micronutrients are important to delay progression and improve clinical symptoms in IBD patients.

The Occurrence of Depression Among Adults With Sickle Cell Disease in Saudi Arabia

Introduction Sickle cell disease (SCD) is recognized as a widely prevalent genetic disorder that impacts individuals globally and is inherited within families. The primary cause of SCD is a singular genetic mutation that affects the globin chain of the hemoglobin protein. Depression and its symptoms are frequently observed in individuals with SCD. This observation has led to a higher probability of adverse health outcomes. Therefore, the primary objective of this study was to analyze depression among Saudi Arabian adults with sickle cell disease. Method The online survey questionnaire was administered in both Arabic and English to collect essential information regarding SCD distress among the urban adult population in Saudi Arabia, using a cross-sectional study design. Data analysis was conducted using IBM SPSS software version 25 (IBM Corp., Armonk, NY, USA) and Microsoft Excel (Microsoft Corporation, Redmond, WA, USA). The study was designed with a statistical power of 80% at a cut-off value of 0.05 and 0.2. Diverse statistical approaches have been utilized to examine the connection between independent variables, including methods such as Chi-square analysis and Pearson's statistical assessment. Result A total of 685 respondents were included in the survey for this study, with the majority of the participants from the eastern region (31%) and between the age groups of 25 and 30 years (34%) showing a lot of enthusiasm There was a clear dominance of the Saudi population (71%) who spoke Arabic (83%). Female (65%) participants showed more interest in this survey. The collected data were organized comprehensively in tables to facilitate a better understanding of the study's findings. P-values less than 0.05 were considered significant for the obtained results. Conclusion The study has shown that there were a variety of depression entanglements as a result of SCD, but they were handled well with the necessary measures by medical care professionals with much-needed psychological counseling and well-equipped medical facilities.

Vitamin D Deficiency and Cardiovascular Mortality: Retrospective Analysis "Siena Osteoporosis" Cohort

Vitamin D is a fat-soluble vitamin that plays a key role in bone metabolism, particularly concerning the regulation of calcium and phosphate homeostasis. Cardiovascular disease (CVD) is the main cause of morbidity and mortality in Western countries. Knowledge of the role of vitamin D in CVD arose from evidence of the vitamin D receptor (VDR) inside the cardiovascular system. In this retrospective analysis, we investigated the relationships between vitamin D status and hospitalization for heart failure (HF), overall mortality and cardiovascular mortality. Between 2004 and 2009, age-stratified, random sampling of elderly men and postmenopausal women in the primary care registers of Siena residents was performed. In total, 174 males (mean ± SD, 65.9 ± 6 years) and 975 females (62.5 ± 6 years) were enrolled in the study. We investigated the association between 25OHD status and hospitalization for HF or causes of mortality. A total of 51 subjects (12 males and 39 females) had been hospitalized for acute HF. At the end of the survey, 931 individuals were alive, while 187 had died (43 males and 144 females). A greater proportion of deceased patients showed low 25OHD (particularly patients with levels below 20 ng/mL). A similar trend was observed concerning the prevalence of patients with 25OHD levels below 20 ng/mL who died from stroke (RR = 2.15; 95% CIs 0.98-4.69; p = 0.06). Low 25OHD levels may be predictive of cardiovascular mortality. Whether vitamin deficiency represents a primitive cause or is a simple bystander in increased cardiovascular mortality should be further investigated in prospective large cohort studies specifically designed to assess CVD risk, including a detailed assessment of cardiac dysfunction and the characterization of atherosclerotic lesions.

Increased dietary vitamin D3 and calcium partially alleviate heat stress symptoms and inflammation in lactating Holstein cows independent of dietary concentrations of vitamin E and selenium

Twelve multiparous Holstein cows (42.2 ± 5.6 kg of milk/d; 83 ± 27 d in milk) were used in a split-plot design testing the effects of mineral and vitamin supplementation on the time course of animal performance, metabolism, and inflammation markers during heat stress. The main plot was the average concentrations of dietary vitamin E and Se (adequate: 11.1 IU/kg of vitamin E and 0.55 mg/kg of Se, and high: 223 IU/kg of vitamin E and 1.8 mg/kg of Se, respectively). Within each plot, cows were randomly assigned to (1) heat stress (HS) with adequate concentrations of vitamin D₃ and Ca (1,012 IU/kg and 0.73%, respectively), (2) HS with high concentrations of vitamin D₃ and Ca (HS+D₃/Ca; 3,764 IU/kg and 0.97%, respectively), or (3) pair-feeding (PF) in thermoneutrality with adequate concentrations of vitamin D₃ and Ca (1,012 IU/kg and 0.73% Ca) in a Latin square design with 14-d periods and 7-d washouts. The highest rectal temperature was recorded at 1700 h for HS (39.4°C; mean of d 1 to 14), being 1.2 and 0.8°C greater than for PF and HS+D₃/Ca, respectively. Respiratory rate and water intake were higher in HS (73 breaths/min and 115 L/d, respectively) relative to PF (28 breaths/min and 76 L/d). Heat stress decreased dry matter intake progressively, reaching a nadir on d 5 to 7 (33% reduction) and was not different between treatments. Milk yield decreased progressively in all treatments, but remained greater in PF relative to HS from d 3 to 14 (10%), whereas HS and HS+D₃/Ca were not different. Milk fat, protein, and lactose concentrations and yields were lower in HS relative to PF from d 3 to 14, but not different between HS and HS+D₃/Ca. Relative to PF, preprandial insulin concentrations were increased in HS, whereas plasma nonesterified fatty acids were decreased on d 7 and 14. Plasma lipopolysaccharide-binding protein concentrations increased in HS cows on d 7 and 14, respectively, relative to PF, whereas they were reduced in HS + D₃/Ca on d 14. Plasma C-reactive protein, tumor necrosis factor-α, and fecal calprotectin were increased in HS relative to both PF and HS+D₃/Ca on d 7 and 14. Rectal temperature was positively associated with plasma lipopolysaccharide-binding protein (r = 0.72), tumor necrosis factor-α (r = 0.74), C-reactive protein (r = 0.87), and with milk somatic cells (r = 0.75). Plasma 8-hydroxy-2-deoxyguanosine concentrations presented a 3-way interaction, where 8-hydroxy-2-deoxyguanosine was lower in HS than in PF on d 7 and 14, and lower in HS+D₃/Ca relative to HS on d 14 in the adequate vitamin E and Se treatment, but no effects were observed in the high vitamin E and Se group. Plasma superoxide dismutase concentrations increased over time, and were higher in HS relative to PF on d 14, whereas HS+D₃/Ca was similar to HS. Heat stress markedly reduced milk production and milk components while increasing markers of leaky gut and inflammation. In contrast, vitamin D₃ and Ca supplementation reduced hyperthermia (d 7-14), markers of leaky gut, and inflammation independent of dietary concentrations of vitamin E and Se.

Comparison of the anti-inflammatory effects of vitamin E and vitamin D on a rat model of dextran sulfate sodium-induced ulcerative colitis

The present study aimed to compare the clinical effects of vitamin E and vitamin D on a rat model of dextran sulfate sodium (DSS)-induced ulcerative colitis (UC), and to elucidate the underlying mechanisms associated with changes in the levels of cytokines. After successful establishment of the rat model of DSS-induced UC, prednisolone (1 mg/kg), vitamin D (50 ng) and vitamin E (6, 30 and 150 IU/kg) were orally administered for 1 week. The pharmacodynamics were evaluated by a daily combination of clinical observation (CO) scores, histopathological evaluations and assessment of molecular markers of inflammation. Administration of vitamin D, vitamin E (30 and 150 IU/kg), prednisolone, and the combination of vitamin D and vitamin E resulted in a decrease in CO scores. The severity of inflammation of the colon was markedly alleviated in the treatment groups compared with that in the untreated DSS group according to the results of histopathological examination; however, they showed different inhibitory effects on the levels of some cytokines. In conclusion, the present results indicated that oral administration of vitamin E could promote recovery of DSS-induced UC by the inhibition of proinflammatory cytokines, and that its underlying mechanism may differ from that of vitamin D and glucocorticoid drugs.

Antibody production in mice requires neither vitamin D, nor the vitamin D receptor

The vitamin D receptor as well as its ligand have been localized to various immune tissues and cells. These observations have led researchers to hypothesize a role for vitamin D in the immune system. However, a specific role for vitamin D in immunity has yet to be clearly delineated. The work in this report was undertaken to determine if mounting an antibody response is altered in the face of vitamin D-deficiency or when the signaling pathway is eliminated by removal of the nuclear receptor. This investigation provides direct evidence vitamin D is not necessary for producing antibodies, a process paramount for optimal attack against many foreign organisms. The idea that vitamin D plays a significant role in immunity has been proposed repeatedly for many years. To address this important idea we have carried out studies in mice to determine if vitamin D plays a significant role in antibody production. Two animal models were utilized: mice depleted of vitamin D and mice devoid of the vitamin D receptor. Further, a possible role of hypocalcemia resulting from vitamin D deficiency in antibody production was determined. Neither the absence of vitamin D or the vitamin D receptor nor hypocalcemia affected the ability of mice to mount an antibody response to an antigen challenge. Thus, we found no evidence that vitamin D or normal serum calcium is required for this major form of immunity.

Pleiotropic Effects of Vitamin D in Patients with Inflammatory Bowel Diseases

The multifaceted activity of vitamin D in patients with inflammatory bowel disease (IBD) presents a challenge for further research in this area. Vitamin D is involved in the regulation of bone mineral metabolism, it participates in the regulation of the immune system, and it is an underlying factor in the pathogenesis of IBD. Additionally, vitamin D affects Th1 and Th2 lymphocytes, influencing the release of cytokines and inhibiting tumor necrosis factor (TNF) expression and the wnt/β-catenin pathway. As far as IBDs are concerned, they are associated with microbiota dysbiosis, abnormal inflammatory response, and micronutrient deficiency, including vitamin D hypovitaminosis. In turn, the biological activity of active vitamin D is regulated by the vitamin D receptor (VDR) which is associated with several processes related to IBD. Therefore, in terms of research on vitamin D supplementation in IBD patients, it is essential to understand the metabolic pathways and genetic determinants of vitamin D, as well as to identify the environmental factors they are subject to, not only in view of osteoporosis prevention and therapy, but primarily concerning modulating the course and supplementation of IBD pharmacotherapy.

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.

Effect of Vitamin D on Graft-versus-Host Disease

The different cell subsets of the immune system express the vitamin D receptor (VDR). Through the VDR, vitamin D exerts different functions that influence immune responses, as previously shown in different preclinical models. Based on this background, retrospective studies explored the impacts of vitamin D levels on the outcomes of patients undergoing allogeneic hematopoietic stem-cell transplantation, showing that vitamin D deficiency is related to an increased risk of complications, especially graft-versus-host disease. These results were confirmed in a prospective cohort trial, although further studies are required to confirm this data. In addition, the role of vitamin D on the treatment of hematologic malignancies was also explored. Considering this dual effect on both the immune systems and tumor cells of patients with hematologic malignancies, vitamin D might be useful in this setting to decrease both graft-versus-host disease and relapse rates.

Modulation of Fecal Metabolites by Heat Stress and Diet, and Their Association with Inflammation and Leaky Gut Markers in Dairy Cows

The analysis of fecal metabolite profiles could provide novel insights into the mechanisms underlying animal responses to environmental stressors and diet. We aimed to evaluate the effects of a 14-day heat stress period and of dietary mineral and vitamin supplementation under heat stress on fecal metabolite profiles and to investigate their associations with physiological markers of heat stress, leaky gut, and inflammation in lactating dairy cows. Twelve multiparous Holstein cows (42.2 ± 5.6 kg milk/d; 83.4 ± 27.1 DIM) were enrolled in an experiment in a split-plot design. The main plot was the level of dietary vitamin E and Se, as follows: (1) low (L-ESe; 20 IU/kg vitamin E, 0.3 ppm Se) or (2) high (H-ESe 200 IU/kg vitamin E, 1.2 ppm Se). Within each plot, six cows were randomly assigned to either (1) heat stress (HS; Total Humidity Index (THI): 82), (2) pair-feeding in thermoneutrality (TNPF; THI = 64), or (3) HS with vitamin D₃ and Ca supplementation (HS+DCa; 1820 IU/kg and 1.5% Ca; THI: 82) in a replicated 3 × 3 Latin square design with 14-day periods and 7-day washouts. The concentrations of 94 metabolites were determined in fecal samples, including amino acids, fatty acids, biogenic amines, and vitamins. Relative to the L-ESe group, the H-ESe group increased α-tocopherol by threefold, whereas δ-tocopherol was decreased by 78% (P_FDR < 0.01). Nevertheless, correlation analysis between α-tocopherol and all the others fecal metabolites or physiological heat stress measures did not show significant associations. No interactions between main plot and treatments were observed. Relative to TNPF, HS increased plasma tumor necrosis factor-alpha (TNF-α), plasma lipopolysaccharide-binding protein (LBP), milk somatic cell counts (SCC), respiratory rates, rectal temperatures, fecal tridecylic and myristic acids, vitamin B₇, and retinol, whereas it decreased fecal amino acids such as histidine, methyl histidine, acetyl ornithine, and arginine (P_FDR < 0.05). In contrast, HS+DCa increased fecal methyl histidine concentrations and reduced milk SCC, plasma TNF-α, and LBP, as well as rectal temperatures. Discriminant analysis revealed fecal histidine, taurine, acetyl ornithine, arginine, β-alanine, ornithine, butyric + iso-butyric acid, plasma non-esterified fatty acids, TNF-α, LBP, C-reactive protein, and milk SCC were predictive of HS. Several metabolites were predictive of HS+DCa, although only tryptophan was discriminant relative to HS. In conclusion, both heat stress and the supplementation of vitamin D₃ and Ca can influence the fecal metabolome of dairy cows experiencing heat stress, independently of dietary levels of vitamin E and Se. Our results suggest that some fecal metabolites are well associated with physiological measures of heat stress and may thus provide insights into the gut-level changes taking place under heat stress in dairy cows.

Beneficial Role of Vitamin D on Endothelial Progenitor Cells (EPCs) in Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading cause of death in the world. Endothelial progenitor cells (EPCs) are currently being explored in the context of CVD risk. EPCs are bone marrow derived progenitor cells involved in postnatal endothelial repair and neovascularization. A large body of evidence from clinical, animal, and in vitro studies have shown that EPC numbers in circulation and their functionality reflect endogenous vascular regenerative capacity. Traditionally vitamin D is known to be beneficial for bone health and calcium metabolism and in the last two decades, its role in influencing CVD and cancer risk has generated significant interest. Observational studies have shown that low vitamin D levels are associated with an adverse cardiovascular risk profile. Still, Mendelian randomization studies and randomized control trials (RCTs) have not shown significant effects of vitamin D on cardiovascular events. The criticism regarding the RCTs on vitamin D and CVD is that they were not designed to investigate cardiovascular outcomes in vitamin D-deficient individuals. Overall, the association between vitamin D and CVD remains inconclusive. Recent clinical and experimental studies have demonstrated the beneficial role of vitamin D in increasing the circulatory level of EPC as well as their functionality. In this review we present evidence supporting the beneficial role of vitamin D in CVD through its modulation of EPC homeostasis.

Inflammation- and Gut-Homing Macrophages, Engineered to De Novo Overexpress Active Vitamin D, Promoted the Regenerative Function of Intestinal Stem Cells

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gut. Available drugs aim to suppress gut inflammation. These drugs have significantly delayed disease progression and improved patients’ quality of life. However, the disease continues to progress, underscoring the need to develop novel therapies. Aside from chronic gut inflammation, IBD patients also experience a leaky gut problem due to damage to the intestinal epithelial layer. In this regard, epithelial regeneration and repair are mediated by intestinal stem cells. However, no therapies are available to directly enhance the intestinal stem cells’ regenerative and repair function. Recently, it was shown that active vitamin D, i.e., 1,25-dihydroxyvitamin D or 1,25(OH)₂D, was necessary to maintain Lgr5⁺ intestinal stem cells, actively cycling under physiological conditions. In this study, we used two strategies to investigate the role of 1,25(OH)₂D in intestinal stem cells’ regenerative function. First, to avoid the side effects of systemic high 1,25(OH)₂D conditions, we used our recently developed novel strategy to deliver locally high 1,25(OH)₂D concentrations specifically to inflamed intestines. Second, because of the Lgr5⁺ intestinal stem cells’ active cycling status, we used a pulse-and-chase strategy via 5-bromo-2′-deoxyuridine (BrdU) labeling to trace the Lgr5⁺ stem cells through the whole epithelial regeneration process. Our data showed that locally high 1,25(OH)₂D concentrations enhanced intestinal stem cell migration. Additionally, the migrated cells differentiated into mature epithelial cells. Our data, therefore, suggest that local delivery of high 1,25(OH)₂D concentrations is a promising strategy to augment intestinal epithelial repair in IBD patients.

Factors determining the serum 25-hydroxyvitamin D response to vitamin D supplementation: Data mining approach

Vitamin D supplementation has been shown to prevent vitamin D deficiency, but various factors can affect the response to supplementation. Data mining is a statistical method for pulling out information from large databases. We aimed to evaluate the factors influencing serum 25-hydroxyvitamin D levels in response to supplementation of vitamin D using a random forest (RF) model. Data were extracted from the survey of ultraviolet intake by nutritional approach study. Vitamin D levels were measured at baseline and at the end of study to evaluate the responsiveness. We examined the relationship between 76 potential influencing factors on vitamin D response using RF. We found several features that were highly correlated to the serum vitamin D response to supplementation by RF including anthropometric factors (body mass index [BMI], free fat mass [FFM], fat percentage, waist-to-hip ratio [WHR]), liver function tests (serum gamma-glutamyl transferase [GGT], total bilirubin, total protein), hematological parameters (mean corpuscular volume [MCV], mean corpuscular hemoglobin concentration [MCHC], hematocrit), and measurement of insulin sensitivity (homeostatic model assessment of insulin resistance). BMI, total bilirubin, FFM, and GGT were found to have a positive relationship and homeostatic model assessment for insulin resistance, MCV, MCHC, fat percentage, total protein, and WHR were found to have a negative correlation to vitamin D concentration in response to supplementation. The accuracy of RF in predicting the response was 93% compared to logistic regression, for which the accuracy was 40%, in the evaluation of the correlation of the components of the data set to serum vitamin D.

Novel biomarker for predicting sepsis mortality: vitamin D receptor

Objective

There are currently no studies on the role of vitamin D receptor (VDR) levels as a cause of or risk factor for sepsis. We aimed to establish the association between VDR levels and 28-day mortality in critically ill patients with sepsis.

Methods

This prospective cross-sectional observational study included 148 patients diagnosed with sepsis who were treated in the intensive care unit. We measured VDR levels, laboratory characteristics, and health scores and related them to survival.

Results

The 148 patients included 96 survivors and 52 non-survivors, with VDR levels of 1.92 and 1.36 ng/mL, respectively. Baseline VDR was a significant predictor of 28-day mortality, with an area under the curve of 0.778. A low VDR level was significantly associated with lower overall survival in patients with sepsis according to Kaplan–Meier curve analysis. VDR levels were also negatively correlated with lactate, C-reactive protein, acute physiological and clinical health evaluation (APACHE) II and sequential organ failure assessment (SOFA) scores, and disease severity.

Conclusions

VDR levels were associated with high 28-day mortality and negatively correlated with lactate, C-reactive protein, APACHE II and SOFA scores, and disease severity in patients with sepsis. VDR levels can predict poor outcomes in patients with sepsis.

Vitamin D and Vascular Disease

Cardiovascular disease (CVD) is a major cause of morbidity and mortality worldwide. Vitamin D deficiency has been identified as a potential risk factor for a number of diseases unrelated to the classical skeletal pathophysiology, such as cancer and CVD, but the effects of vitamin D supplementation are less clear. Purpose of this narrative review is to discuss the evidence suggesting an association between vitamin D status and CVD as well as the results of supplementation studies. Vitamin D deficiency has been associated with CVD risk factors such as hypertension, dyslipidemia and diabetes mellitus as well as with cardiovascular events such as myocardial infarction, stroke and heart failure. While vitamin D deficiency might contribute to the development of CVD through its association with risk factors, direct effects of vitamin D on the cardiovascular system may also be involved. Vitamin D receptors are expressed in a variety of tissues, including cardiomyocytes, vascular smooth muscle cells and endothelial cells. Moreover, vitamin D has been shown to affect inflammation, cell proliferation and differentiation. While observational studies support an association between low plasma vitamin D levels and increased risk of CVD, Mendelian randomization studies do not support a causal association between the two. At present, high quality randomized trials do not find evidence of significant effects on CVD endpoints and do not support supplementation of vitamin D to decrease CVD events.

The Impact of Vitamin D on Response to Anti-tumor Necrosis Factor-α Therapy in Children With Inflammatory Bowel Disease

OBJECTIVES

Experimental studies have shown that vitamin D has an immunomodulatory effect on the innate and adaptive immune systems. Associations between vitamin D deficiency and development or progression of inflammatory bowel diseases (IBDs) are reported, but a cause-and-effect relationship between pretreatment 25 hydroxyvitamin D [25(OH)D] levels and response to anti-tumor necrosis factor-α (anti-TNF) therapy is not established.

METHODS

This retrospective study evaluated pediatric IBD patients who had 25(OH)D levels drawn within 3 months of initiating infliximab and/or adalimumab treatment. Demographic features, Paris classification, baseline 25(OH)D levels, disease activity, and laboratory results before and after 3 months of anti-TNF therapy were collected. The interaction between vitamin D insufficiency at induction and lack of response to anti-TNF therapy at 3 months was determined.

RESULTS

Of the 383 patients, 76 met inclusion criteria. Sixty-five patients (85.5%) had Crohn disease (CD) and 11 (14.5%) had ulcerative colitis. Seven patients had 25(OH)D levels obtained during both infliximab and adalimumab induction; hence 83 subjects were evaluated (infliximab: 70 patients, adalimumab: 13 patients). 25(OH)D <30 ng/mL was found in 55 of 83 (66.3%) subjects. There were no differences in gender, IBD type, disease activity scores between vitamin D-sufficient and vitamin D-insufficient groups. In CD, proximal gastrointestinal tract inflammation was associated with vitamin D insufficiency (P = 0.019), but other Paris classification parameters and laboratory results were similar in 2 groups. Early termination of anti-TNF therapy was significantly higher in patients who had vitamin D insufficiency (14.5% vs 0%, P = 0.034).

CONCLUSIONS

Vitamin D insufficiency before anti-TNF treatment may result in poor response to induction therapy.

Association Between Serum Vitamin D Level and Ménière's Disease

OBJECTIVES

Ménière's disease (MD) is a well-known inner ear disease; however, the etiopathogenesis is unknown. Several factors may be involved. Meanwhile, vitamin D is reported to have an important role in inner ear physiology. The aim of this study is to evaluate the relation between vitamin D deficiency and MD.

STUDY DESIGN

This matched case-control study compared serum vitamin D levels between patients with definite MD and those without it.

SETTING

The study was done between August 2018 and December 2019 at Ghaem University Hospital in Mashhad, Iran.

METHODS

Twenty-eight patients with definite MD were matched with a group of 84 healthy individuals, regarding age, sex, body mass index, and occupation (indoor vs outdoor). The serum level of vitamin D (25-hydroxyvitamin D3) was measured in both groups.

RESULTS

The mean ± SD vitamin D level was 18.9 ± 9.7 ng/mL in the case group and 25.2 ± 13.7 ng/mL in the control group (P = .027). There was a significant difference between the case and control groups according to the results of the conditional logistic regression model (P = .03; adjusted odds ratio, 0.96). In the MD group, 17 (60.7%) patients were vitamin D deficient, 6 (21.4%) insufficient, and only 5 (17.9%) sufficient.

CONCLUSIONS

The results of this study show that serum vitamin D level in MD is significantly lower than that of the control group. However, the role of vitamin D supplementation in the management of MD needs further study.

LEVEL OF EVIDENCE

4.

Diarrheal Mechanisms and the Role of Intestinal Barrier Dysfunction in Campylobacter Infections

Campylobacter enteritis is the most common cause of foodborne bacterial diarrhea in humans. Although various studies have been performed to clarify the pathomechanism in Campylobacter infection, the mechanism itself and bacterial virulence factors are yet not completely understood. The purpose of this chapter is to (i) give an overview on Campylobacter-induced diarrheal mechanisms, (ii) illustrate underlying barrier defects, (iii) explain the role of the mucosal immune response and (iv) weigh preventive and therapeutic approaches. Our present knowledge of pathogenetic and diarrheal mechanisms of Campylobacter jejuni is explained in the first part of this chapter. In the second part, the molecular basis for the Campylobacter-induced barrier dysfunction is compared with that of other species in the Campylobacter genus. The bacteria are capable of overcoming the intestinal epithelial barrier. The invasion into the intestinal mucosa is the initial step of the infection, followed by a second step, the epithelial barrier impairment. The extent of the impairment depends on various factors, including tight junction dysregulation and epithelial apoptosis. The disturbed intestinal epithelium leads to a loss of water and solutes, the leak flux type of diarrhea, and facilitates the uptake of harmful antigens, the leaky gut phenomenon. The barrier dysfunction is accompanied by increased pro-inflammatory cytokine secretion, which is partially responsible for the dysfunction. Moreover, cytokines also mediate ion channel dysregulation (e.g., epithelial sodium channel, ENaC), leading to another diarrheal mechanism, which is sodium malabsorption. Future perspectives of Campylobacter research are the clarification of molecular pathomechanisms and the characterization of therapeutic and preventive compounds to combat and prevent Campylobacter infections.

Molecular mechanism mediating enteric bacterial translocation after severe burn: the role of cystic fibrosis transmembrane conductance regulator

Background

Gut ischemia and hypoxia post severe burn leads to breakdown of intestinal epithelial barrier and enteric bacterial translocation (EBT), resulting in serious complications, such as systemic inflammatory response syndrome, sepsis and multiple organ failure. Cystic fibrosis transmembrane conductance regulator (CFTR) is known to be downregulated by hypoxia and modulate junctional complexes, which are crucial structures maintaining the intestinal barrier. This study aimed to investigate whether CFTR plays a role in both regulating the intestinal barrier and mediating EBT post severe burn, as well as the signaling pathways involved in these processes.

Methods

An in vitro Caco-2 cell model subjected to hypoxic injury and an in vivo mouse model with a 30% total body surface area full-thickness dermal burn were established. DF 508 mice (mice with F508del CFTR gene mutation) were used as an in vivo model to further demonstrate the role of CFTR in maintaining normal intestinal barrier function. QRT-PCR, western blot, ELISA, TER assay and immunofluorescence staining were used to detect the expression and localization of CFTR and tight junction proteins, as well as the function of tight junctions.

Results

Our data indicated that, in Caco-2 cells, the hypoxia condition significantly reduced CFTR expression; activated extracellular signal-regulated kinase and nuclear factor-κB signaling; elevated secretion of inflammatory factors (tumor necrosis factor-α, interleukin-1β and interleukin-8); downregulated zonula occludens-1, occludin and E-cadherin expression; decreased transepithelial electrical resistance values; and led to a cellular mislocation of ZO-1. More importantly, knockdown of CFTR caused similar alterations. The upregulation of inflammatory factors and downregulation of tight junction proteins (ZO-1 and occludin) induced by knockdown of CFTR could be reversed by specific extracellular signal-regulated kinase or nuclear factor-κB inhibition. In support of the in vitro data, exuberant secretion of pro-inflammatory mediators and EBT was observed in the intestine of severely burnt mice in vivo. EBT occurred in DF508 mice (mice with the F508del CFTR gene mutation), accompanied by augmented tumor necrosis factor-α, interleukin-1β and interleukin-8 levels in the ileum compared to wildtype mice. In addition, vitamin D3 was shown to protect the intestinal epithelial barrier from hypoxic injury.

Conclusions

Collectively, the present study illustrated that CFTR and downstream signaling were critical in modulating the intestinal epithelial junction and EBT post severe burn.

Vitamin D and Immune Regulation: Antibacterial, Antiviral, Anti-Inflammatory

Regulation of immune function continues to be one of the most well-recognized extraskeletal actions of vitamin D. This stemmed initially from the discovery that antigen presenting cells such as macrophages could actively metabolize precursor 25-hydroxyvitamin D (25D) to active 1,25-dihydroxyvitamin D (1,25D). Parallel observation that activated cells from the immune system expressed the intracellular vitamin D receptor (VDR) for 1,25D suggested a potential role for vitamin D as a localized endogenous modulator of immune function. Subsequent studies have expanded our understanding of how vitamin D exerts effects on both the innate and adaptive arms of the immune system. At an innate level, intracrine synthesis of 1,25D by macrophages and dendritic cells stimulates expression of antimicrobial proteins such as cathelicidin, as well as lowering intracellular iron concentrations via suppression of hepcidin. By potently enhancing autophagy, 1,25D may also play an important role in combatting intracellular pathogens such as M. tuberculosis and viral infections. Local synthesis of 1,25D by macrophages and dendritic cells also appears to play a pivotal role in mediating T-cell responses to vitamin D, leading to suppression of inflammatory T helper (Th)1 and Th17 cells, and concomitant induction of immunotolerogenic T-regulatory responses. The aim of this review is to provide an update on our current understanding of these prominent immune actions of vitamin D, as well as highlighting new, less well-recognized immune effects of vitamin D. The review also aims to place this mechanistic basis for the link between vitamin D and immunity with studies in vivo that have explored a role for vitamin D supplementation as a strategy for improved immune health. This has gained prominence in recent months with the global coronavirus disease 2019 health crisis and highlights important new objectives for future studies of vitamin D and immune function. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Atherosclerosis and Inflammatory Bowel Disease-Shared Pathogenesis and Implications for Treatment

Atherosclerosis and inflammatory bowel disease (IBD) are often regarded as 2 distinct entities. The commonest manifestation of atherosclerosis is ischemic heart disease (IHD), and an association between IHD and IBD has been reported. Atherosclerosis and IBD share common pathophysiological mechanisms in terms of their genetics, immunology, and contributing environmental factors. Factors associated with atherosclerosis are implicated in the development of IBD and vice versa. Therefore, treatments targeting the common pathophysiology pathways may be effective in both conditions. The current review considers the pathophysiological pathways that are shared between the 2 conditions and discusses the implications for treatment and research.

Association of serum 25-hydroxyvitamin D levels with severe necroinflammatory activity and inflammatory cytokine production in type I autoimmune hepatitis

25-Hydroxyvitamin D [25(OH)D] has been reported to be associated with several chronic liver diseases. The relationship between 25(OH)D and autoimmune hepatitis (AIH) pathogenesis is incompletely understood. We investigated the association of serum total and free 25(OH)D levels with necroinflammatory activity and cytokine levels in 66 patients with AIH diagnosed in our hospital. The median age at AIH diagnosis was 57 years, and the male:female ratio was 7:59. The median serum total 25(OH)D level in therapy-naïve patients with AIH was 14.2 ng/mL (interquartile range [IQR], 11.4–17.9 ng/mL). Of the 66 patients with AIH, 36 had serum total 25(OH)D levels of < 15 ng/mL and were considered to have vitamin D deficiency, and 30 had serum total 25(OH)D levels of ≥ 15 ng/mL. Patients with acute-onset AIH had significantly lower serum total 25(OH)D levels than those with chronic-onset AIH. In particular, serum total 25(OH)D levels were significantly lower in patients with severe forms of AIH. Furthermore, the serum total 25(OH)D level was positively correlated with the serum albumin level and prothrombin time and negatively correlated with the serum total bilirubin level and necroinflammatory activity in AIH. Multivariate logistic regression analysis showed that the serum total 25(OH)D level was an independent factor for severe necroinflammatory activity. Interestingly, AIH patients with serum total 25(OH)D levels of < 15 ng/mL had higher levels of inflammatory cytokines such as interferon-γ and interleukin-33. Free 25(OH)D levels were correlated with total 25(OH)D levels, and the percentage of free 25(OH)D was significantly associated with necroinflammatory activity. In conclusion, 25(OH)D deficiency may play an important role in predicting AIH severity via inflammatory cytokine production.

Vitamin D regulates claudin-2 and claudin-4 expression in active ulcerative colitis by p-Stat-6 and Smad-7 signaling

PURPOSE

The tight junctions (TJ) responsible for the integrity of the intestinal barrier are altered in patients with inflammatory bowel disease (IBD), but the physiopathological mechanisms that lead to this alteration are not yet clear. The aim of this study was to determine whether vitamin D, which regulates the integrity of the epithelial barrier by expressing TJ proteins, reduces claudin-2 (Cl-2) levels by inhibiting Stat-6 phosphorylation and whether it increases claudin-4 (Cl-4) levels by blocking Smad-7 activity.

METHODS

Biopsies were obtained from inflamed and non-inflamed tracts of the right side colon (caecum or ascending colon) from the same patient with active UC. All the patients were affected by a recent flare-up of ulcerative rectocolitis (RCU), with no previous biologic or immunosuppressive therapy, and all the biopsies were obtained before any treatments. The biopsies were cultured in the presence or not of 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃). We also used T84 cells as an in vitro model to perform transfection experiments with Stat-6 and Smad-7.

RESULTS

Our results indicate that 1,25(OH)₂D₃ is able to regulate CL-2 and CL-4 protein levels, which are increased and reduced in the intestinal mucosa of UC patients, respectively. In the biopsies obtained from UC patients 1,25(OH)₂D₃ reduces Cl-2 levels by blocking Stat-6 phosphorylation and increases Cl-4 levels by blocking Smad-7 activity. T84 cells, transfected with siRNA of Stat-6 and Smad-7, showed reduced Cl-2 levels and increased Cl-4 levels, confirming that 1,25(OH)₂D₃ regulates Cl-2 and Cl-4 by decreasing p-Stat-6 and Smad-7 levels.

CONCLUSIONS

Our results indicate that the effects of vitamin D on Cl-2 and Cl-4 are mediated by p-Stat-6 and Smad-7 signal, respectively. The study suggests that vitamin D administration to UC patients could be a useful therapeutic intervention, given that vitamin D deficiency is found in these patients.

Vitamin D-related immunomodulation in patients with liver cirrhosis

OBJECTIVE(S)

Increasing evidence indicates that vitamin D status is linked to severity of liver cirrhosis and patients' survival. However, the potential role of vitamin D-related immunomodulation in hepatic decompensation and patients' mortality in relation to vitamin D deficiency remains unknown. The aim of the current study is to evaluate the association between vitamin D status and vitamin D binding protein (VDBP) levels with serum cytokine and lipopolysaccharide binding protein (LBP) and to examine their role on disease severity and cirrhotics' mortality.

METHODS

One hundred consecutive Caucasian patients with liver cirrhosis were enrolled in the study. 25(OH)D, VDBP, and LBP concentrations were assessed by ELISA. Cytokine tumor necrosis factor-a (TNF-a), interleukin 6 (IL-6), IL-1β, IL-8, IL-10, and IL-12 levels were determined by Cytometric Bead Array.

RESULTS

25(OH)D levels were inversely correlated with CP score, MELD, IL-6, and CP stage and VDBP levels with CP score, MELD, IL-6, IL-8, LBP, and CP stage. Cirrhotics with 25(OH)D deficiency and severe deficiency had significantly higher CP score, increased IL-6 levels and lower VDBP levels. In the multivariate analysis, the independent prognostic factors associated with patients' survival were CP stage B [hazard ratio = 6.75; 95% confidence interval (CI) 1.32, 34.43; P = 0.022], CP stage C (hazard ratio = 7.39; 95% CI 1.41, 38.81; P = 0.018), the presence of hepatocellular carcinoma (hazard ratio = 4.50; 95% CI 1.54, 13.13; P = 0.006) and 25(OH)D levels (hazard ratio = 0.87; 95% CI 0.80, 0.95; P = 0.002).

CONCLUSION

The results show that vitamin D status and VDBP levels are associated with liver cirrhosis severity and patients' mortality, possibly through a proinflammatory immune response.

Use of Vitamin D With Anti-Tumor Necrosis Factor Therapy for Crohn's Disease

Background

Vitamin D (VD) has an important role in regulating gut mucosal immunity, and seems to be inversely linked to disease activity and more frequent relapses in inflammatory bowel disease. In this study, we evaluated patients with Crohn’s disease (CD) treated with anti-tumor necrosis factor (TNF) in association with VD.

Methods

A double-blind, randomized, prospective study was conducted. Thirty patients with a history of moderate to severe CD, in use of anti-TNF, of both sexes, 18 to 70 years, with the dosage of VD < 75 nmol/L (30 ng/mL) were randomized and divided into three groups: group 1 (G1): 10 patients received 2,000 IU VD, per os (PO)/week for 8 weeks; group 2 (G2): 10 patients received 10,000 IU VD, PO/week for 8 weeks; group 3 (G3): 10 patients received 50,000 IU VD, PO/week for 8 weeks. Before and at the end of 8 weeks patients were submitted to VD, fecal calprotectin (FC) and C-reactive protein (CRP) dosage. Follow-up period was 52 weeks, and they are checked for disease activity recurrence (Crohn’s disease activity index (CDAI) > 150, FC > 300 and computerized tomography (CT) scan), FC, CRP, and VD levels.

Results

Increased VD levels were observed in all groups (P < 0.0001). CRP did not change. There was a significant decrease of FC in G3 (1,014 ± 850 vs. 483 ± 564; P = 0.04), no significant decrease in G2 (76,767 ± 751 vs. 535 ± 823; P = 0.2) and increase in G1 (1,101 ± 744 vs. 1,357 ± 819; P = 0.4). During the 52-week follow-up period, it was showed that recurrent disease activity (CDAI > 150, FC > 200 and CT scan) was predominant in patients with VD < 30 group, and the remission rate was predominant in patients with VD > 30 group (P = 0.0001). A statistically significant difference in VD levels was noted in CD patients after 52 weeks that presented flare or disease remission (P = 0.001).

Conclusions

Use of VD associated with anti-TNF treatment may improve clinical response in CD. VD levels greater than 30 ng/mL have better rates of remission.

Baicalin alleviates TNBS-induced colitis by inhibiting PI3K/AKT pathway activation

Inflammatory bowel diseases (IBDs) are chronic immunological disorders of the intestinal tract characterized by persistent inflammation. Baicalin, a type of flavonoid, has exhibited a wide range of pharmacological activities, including immunomodulation and anti-inflammation. However, little is known about the therapeutic role of baicalin in IBD. The aim of the present study was to ascertain whether baicalin could be a therapeutic drug of IBD and investigate its specific mechanisms. In the present study, the results revealed that baicalin not only significantly alleviated TNBS-induced colitis by reducing the release of IL-6, TNF-α and IL-1β and increasing the level of IL-10, but promoted the expression of tight-junction proteins ZO-1 and β-catenin, which may have been achieved by blockage of the PI3K/AKT signaling pathway. In vitro, the results demonstrated that baicalin clearly inhibited the release of TNF-α, IL-6 and IL-1β and promoted the expression of IL-10 in LPS-induced HT-29 cells, and significantly decreased LPS-induced HT-29 cell apoptosis by blockage of the PI3K/AKT signaling pathway. In conclusion, the present research revealed for the first time that baicalin acted as a therapeutic drug in IBD by suppression of the PI3K/AKT signaling pathway.

Vitamin D status influences transcriptional levels of RANKL and inflammatory biomarkers which are associated with activation of PBMC

Vitamin D status is involved in the risk of many chronic diseases including cancer, inflammatory and autoimmune disease. The RANK/RANKL/OPG system is also implicated in the orchestration of immune functions. We aimed to investigate the expression of RANKL, OPG and markers of inflammation and immune activation in peripheral blood mononuclear cells (PBMC) from healthy subjects with different 25(OH)D3 plasma levels. The 25(OH)D3 plasma concentrations were assessed by HPLC. The gene expression was evaluated by qRT-PCR. The expression of CYP27B1 was lower in subjects with 25(OH)D3 levels below 50 nmol/L (deficiency) than subjects with both insufficient and sufficient levels of 25(OH)D3. In subjects with deficiency, we observed the up-regulation of RANKL, TNF-α, IFN-γ, ICAM and LFA-1, and a reduction of the anti-inflammatory cytokines IL-13 and IL-4 in comparison to other subjects. Finally, we found a negative correlation between RANKL mRNA levels and 25(OH)D3 and between 25(OH)D3 and ICAM mRNA levels. A positive correlation between ICAM and RANKL was observed. Our results give evidence of the modulatory effects of circulating 25(OH)D3 levels on gene expression of biomarkers of immune activation in PBMC, suggesting the possible use of PBMC as ex-vivo model to characterize molecular mechanisms of immune/inflammatory response in hypovitaminosis conditions.

Cardioprotective Effect of Paricalcitol on Amitriptyline-Induced Cardiotoxicity in Rats: Comparison of [99mTc]PYP Cardiac Scintigraphy with Electrocardiographic and Biochemical Findings

Taking an overdose of AMT, a commonly prescribed tricyclic antidepressant drug, has an increased risk of sudden cardiac death. The cardiotoxicity of amitriptyline (AMT) is a commonly observed toxicity with high morbidity and mortality rates in emergency departments (ED). Nevertheless, there are still no effective treatment options for AMT-induced cardiotoxicity. The aim of the present study was to evaluate the effects of paricalcitol (PRC), a Vitamin D receptor agonist, using electrocardiographic (ECG), biochemical, and scintigraphic methods. Twenty-eight male Wistar rats were randomly divided into four groups: untreated control (CON), amitriptyline-induced cardiotoxicity (AMT), paricalcitol (PRC), and amitriptyline + paricalcitol (AMT + PRC). Cardiotoxicity was induced by intraperitoneal (i.p) injection of a single-dose AMT (100 mg/kg). PRC was administered as 10 μg/kg (i.p.) after the injection of AMT. We examined ECG, biochemical, and scintigraphic results of PRC administration on AMT-induced changes. Cardiotoxicity of AMT was characterized by conduction abnormalities (increased QRS complex, T wave, and QT interval duration and elevation of ST segment amplitude), elevated ^99mTechnetium Pyrophosphate ([^99mTc]PYP) uptake, and increased cardiac troponin T (cTnT) levels. Treatment with PRC significantly decreased all AMT-associated conduction abnormalities in ECG (p < 0.001), and decreased [^99mTc]PYP uptake (p < 0.001) and serum cTnT level (p < 0.001). The present study indicated that the vitamin D receptor agonist paricalcitol could decrease the AMT-induced cardiotoxicity. This suggests [^99mTc]PYP as a non-invasive method for the evaluation of myocardial injury induced by AMT. According to the results of the present study, PRC has beneficial effects on AMT-induced cardiotoxicity.

Vitamin D metabolism in dogs and cats and its relation to diseases not associated with bone metabolism

Due to the presence of receptors in the cells of numerous body tissues, vitamin D is associated with several physiological functions that go beyond calcium and phosphorus homoeostasis and control of bone metabolism in the body. In humans, several studies have associated lower vitamin D concentrations with numerous diseases, such as cancer, heart disease, autoimmune diseases and infectious diseases, and also with an increase in the total mortality rate of the population. Recently, this nutrient started to gain importance in veterinary medicine, and several articles have shown a correlation between low vitamin D status and diseases unrelated to bone metabolism. The present review aims to highlight the recent publications that investigated this relationship, bringing the evidence that exists so far in dogs and cats.

Decreased 25-Hydroxyvitamin D Levels in Patients With Vestibular Neuritis

Objective: Vestibular neuritis (VN) is characterized by acute onset of vertigo, nausea, and vomiting, without auditory or other neurological symptoms. Although the pathogenesis of VN is not yet clear, many studies have shown that a pro-inflammatory environment can lead to the induction and progression of the disease. Considering the importance of vitamin D in modulating the activation, proliferation, and differentiation of inflammatory physiological processes, we hypothesized that decreased serum vitamin D may be associated with the development of VN. In this study, we evaluated serum levels of 25-hydroxyvitamin D [25(OH)D] in patients presenting acutely with VN and healthy controls and investigated the possible correlation of serum 25(OH)D levels with VN.

Methods: A total of 59 consecutive patients diagnosed with VN within 7 days of symptom onset and 112 age- and sex-matched healthy controls referred to Hwa Mei Hospital, University of Chinese Academy of Science, between March 2017 and March 2019 were recruited. Demographic and clinical data, such as age, sex, height, weight, living habits, ongoing health problems, and medication history, for all subjects were recorded, and levels of 25(OH)D were measured and compared.

Results: Serum levels of 25(OH)D were lower in patients with VN than in controls (19.01 ± 6.53 vs. 22.94 ± 6.74 ng/ml, p < 0.001). Patients with VN had a higher frequency of vitamin D deficiency (61.0 vs. 34.8%, P = 0.001) than did controls. Regression analyses demonstrated that vitamin D deficiency was associated with VN, with an odds ratio of 4.53 (95% CI = 1.342–15.279, P = 0.015).

Conclusion: This prospective study is the first to evaluate serum 25(OH)D levels in patients with VN and found that decreased serum 25(OH)D may be associated with VN occurrence.

Effect of single-dose injection of vitamin D on immune cytokines in ulcerative colitis patients: a randomized placebo-controlled trial

Ulcerative colitis (UC) is a chronic recurrent inflammation of the colon. It has been proposed that the UC pathogenesis may be related to vitamin D deficiency and/or vitamin D administration in UC patients may have an ameliorating effect on the intestinal inflammation. The aim of this study was to assess the effect of vitamin D on the serum levels of immune cytokines in UC patients. In this double-blind randomized controlled trial, 90 mild-to-moderate UC patients were assigned to get either a single muscular injection of 7.5 mg vitamin D3 or 1 mL normal saline as placebo. Three months later serum levels of IL-4, IL-10, IL-12p70, IFN-γ, and TNF-α were measured. Two group variables were compared using independent t-test and analysis of covariance (ANCOVA). There was a significant increase in vitamin D only in the vitamin D group. Compared to placebo, vitamin D had significant decreasing effects on serum TNF-α, IFN-γ, and IL12p70 levels, but it had no significant effect on serum levels of IL4 and IL10. Vitamin D seems to inhibit Th1 immune responses and have no effect on Th2 responses. The findings of this study support several in vitro studies, which suggest a therapeutic immunomodulatory potential of vitamin D.

How would serum 25(OH)D level change in patients with inflammatory bowel disease depending on intestinal mucosa vitamin D receptor (VDR) and vitamin D1-α hydroxylase (CYP27B1)?

BACKGROUND/AIMS

To investigate how the serum 25-hydroxyvitamin D (25(OH)D) level change in patients with inflammatory bowel disease (IBD) and investigate the intestinal mucosa vitamin D receptor (VDR) and vitamin D1-α hydroxylase (CYP27B1) expressions.

MATERIALS AND METHODS

A total of 105 patients with IBD were enrolled in the present study, including 49 cases with ulcerative colitis (UC) and 56 cases with Crohn's disease (CD), compared with 45 healthy controls (CON) during the same period by testing the permeability of the intestinal mucosa. The expressions of VDR and CYP27B1 in the intestinal mucosa were detected, so as the serum endotoxin, tumor necrosis factor (TNF)-α, and 25(OH)D levels.

RESULTS

The lactulose and mannitol absorption ratio (LMR) and serum endotoxin and TNF-α levels were significantly higher in the IBD group than in the CON group (p<0.05). The levels of LMR, endotoxin, and TNF-α were higher in the UC group than in the CD group, but 25(OH)D was lower (p<0.05). VDR in the IBD and UC groups was down-regulated when compared with the CON group (p<0.05), but there was no significance between them (p>0.05). CYP27B1 in the IBD and CD groups was significantly up-regulated compared with the CON group (p<0.05), with no significant difference between them (p>0.05).

CONCLUSION

Patients with IBD exhibit vitamin D metabolism imbalance, lower serum 25(OH)D, and lower VDR expression, but higher CYP27B1 expression in the colonic mucosa. However, VDR and CYP27B1 cannot be used to distinguish UC and CD.

Vitamin D aggravates breast cancer by inducing immunosuppression in the tumor bearing mouse

The aim of this approach is to test the effects and related mechanism of vitamin D (VD) treatment on the outcomes of breast cancer. BALB/c mice were injected with 4T1 breast cancer cell suspension. The test group was treated with VD reagent. The survival and tumor size of mice were observed. The proliferation of 4T1 in vitro was detected by MTS analysis. The changes of immune parameters and microenvironment in mice were evaluated by flow cytometry and real-time RT-PCR. Our results demonstrate that VD administration caused a decline in survival time and raising the volume of tumor, the decreasing numbers of CD3⁺CD4⁺ T, CD3⁺CD8⁺ T and CD4⁺T-bet⁺IFN-γ⁺ Th1 cells and transcriptions of T-bet and IFN-γ, an increasing number of myeloid-derived suppressor cells and transcription of TGF-β. Our data suggest that the routine clinical application of any strategies targeting VD status for breast cancer therapy is deserved serious consideration.

Vitamin D and Otitis Media

PURPOSE OF REVIEW

To examine the relationship between vitamin D and otitis media.

RECENT FINDINGS

Vitamin D deficiency has been associated with several respiratory diseases, including otitis media. Vitamin D supplementation may reduce the risk of otitis media. This relationship may be explained by vitamin D supporting the immune system by upregulating antimicrobial peptides which are effective against otopathogens and biofilm formation, supporting a less inflammatory immune response, or promoting beneficial commensal bacteria. This review will explore risk factors of both otitis media and vitamin D deficiency, the evidence of vitamin D being beneficial for various forms of otitis media, and possible mechanisms of action.

The vitamin D positive feedback hypothesis of inflammatory bowel diseases

While it appears that there are a variety of factors that exacerbate IBD, it is frustrating that symptoms can persist and worsen even when environmental insults are removed. We suggest that there may be a positive feedback loop which perpetuates the inflammatory response in IBD patients. The loop is triggered by vitamin D deficiency which reduces calcium uptake. Lowered vitamin D and calcium interfere with anti-inflammatory pathways. Inflammation of the mucosa inhibits absorption of calcium and thus perpetuates the reduced anti-inflammatory response. A number of predictions follow from this hypothesis and are supported by geographic and lifestyle patterns in IBD incidence and prevalence.

Serum vitamin D but not zinc levels are associated with different disease activity status in patients with inflammatory bowel disease

The incidence of inflammatory bowel disease (IBD) is increasing and the pathogenesis is still not completely understood. Micronutrients like vitamin D [25 (OH)D] and zinc play an important role in enzyme activities and the immune system. As the 25 (OH)D-receptor has been shown to be downregulated in patients with IBD, 25 (OH)D may emerge as a predictive marker for disease improvement. Studies on relationship of both micronutrients in IBD patients are lacking.We retrospectively evaluated serum levels of 25(OH)D and zinc together with baseline characteristics of 232 IBD patients. Uni- and multivariate analyses were performed for association between serum levels of 25(OH)D and zinc with clinical and deep remission (CR and DR).155 Crohn's disease (CD) and 77 ulcerative colitis (UC) patients were included. 54% (n = 125) and 6% (n = 14) of IBD patients showed deficient serum 25(OH)D levels below 20 ng/mL and zinc levels below 7 μmol/L. Serum 25(OH)D levels were significantly higher in IBD patients with CR (P = .02) and DR (P < .001) but not serum zinc levels, respectively. Serum 25(OH)D levels (P = .008), anti-tumor-necrosis-factor-α-trough-concentration (anti-TNF-α-TC) (P = .02) and CRP level (P = .02) were independently associated with CR in CD patients. Serum 25(OH)D threshold of 19 ng/mL discriminated CD patients with or without CR, having an area under the receiver operating curve analysis (AUROC) of 0.77 [95%-confidence interval (CI): 0.68-0.85]. In multivariate analysis serum 25(OH)D levels (P = .04) and anti-TNF-α-TC (P = .04) were associated with DR in CD patients. Serum 25(OH)D threshold of 26 ng/mL discriminated CD patients with or without DR, having an AUROC of 0.75 (95%-CI: 0.68-0.83).Serum 25(OH)D (P = .04) and fecal calprotectin levels (P = .04) were independently correlated with CR in UC patients. Serum 25(OH)D threshold of 32 ng/mL discriminated UC patients in CR with an AUROC of 0.83 (95%-CI: 0.71-0.95). Zinc levels did not correlate with disease activity status in CD or UC patients either.In conclusion, beside CRP and fecal calprotectin, serum 25(OH)D levels, but not serum zinc levels, may be an additional useful and noninvasive marker for characterizing different disease activity status of IBD patients. Measurement of serum 25(OH)D in IBD patients may be warranted. 25(OH)D supplementation in deficient IBD patients is recommended.