Treatment of vitamin D deficiency in cystic fibrosis

Influence of the BsmI polymorphism of the vitamin D receptor gene on the levels of vitamin D, inflammatory and oxidative stress profile in patients with cystic fibrosis supplemented with Colecalciferol megadose

OBJECTIVE

Evaluate the influence of the BsmI polymorphism of the vitamin D receptor gene on vitamin D levels, and inflammatory and oxidative stress markers in patients with Cystic Fibrosis supplemented with cholecalciferol megadose.

METHODS

We performed a single-arm, non-randomized pre- and post-study of 17 patients aged 5 to 20 years with cystic fibrosis diagnosed with vitamin D insufficiency/deficiency 25-hydroxy vitamin< 30 ng/mL. Individuals were genotyped for the BsmI polymorphism of the vitamin D receptor gene and all received cholecalciferol supplementation of 4,000 IU daily for children aged 5 to 10 years and 10,000 IU for children over 10 years of age for 8 weeks. Interviews were conducted with personal data, sun exposure, anthropometric and blood samples of 25-hydroxy vitamin parathormone, serum calcium, ultrasensitive C-reactive protein, alpha 1 acid glycoprotein, total antioxidant capacity, malondialdehyde and kidney and liver function. Inter- and intra-group assessment was assessed by paired t-test Anova test or its non-parametric counterparts.

RESULTS

The individuals were mostly male and reported no adverse effects from the use of supplementation, 64 % had 25-hydroxy vitamin levels >30 ng/mL. Patients with BB and Bb genotypes showed increased serum levels of 25-hydroxy vitamin. The group with BB genotype showed a reduction in alpha 1 acid glycoprotein. And individuals with the bb genotype had high levels of malondialdehyde compared to the pre-intervention time.

CONCLUSION

It is concluded that variations of the BsmI polymorphism of the vitamin D receptor gene have different responses in vitamin D levels and markers of inflammation and oxidative stress.

Vitamin D and prebiotics for intestinal health in cystic fibrosis: Rationale and design for a randomized, placebo-controlled, double-blind, 2 x 2 trial of administration of prebiotics and cholecalciferol (vitamin D3) (Pre-D trial) in adults with cystic fibrosis

Individuals with cystic fibrosis (CF) have dysfunctional intestinal microbiota and increased gastrointestinal (GI) inflammation also known as GI dysbiosis. It is hypothesized that administration of high-dose cholecalciferol (vitamin D3) together with a prebiotic (inulin) will be effective, and possibly additive or synergistic, in reducing CF-related GI and airway dysbiosis. Thus, a 2 x 2 factorial design, placebo-controlled, double-blinded, pilot and feasibility, clinical trial was proposed to test this hypothesis. Forty adult participants with CF were block-randomized into one of four groups: 1) high-dose oral vitamin D3 (50,000 IU weekly) plus oral prebiotic placebo daily; 2) oral prebiotic (12 g inulin daily) plus oral placebo vitamin D3 weekly; 3) combined oral vitamin D3 weekly and oral prebiotic inulin daily; and 4) oral vitamin D3 placebo weekly and oral prebiotic placebo. The primary endpoints included 12-week changes in the microbial bacterial communities, gut and airway microbiota richness and diversity before and after the intervention. This pilot study examined whether vitamin D3 with or without prebiotics supplementation was feasible, changed airway and gut microbiota, and reduced dysbiosis, which in turn, may improve health outcomes and quality of life of patients with CF.

Vitamin D for glycemic control following an acute pulmonary exacerbation: A secondary analysis of a multicenter, double-blind, randomized, placebo-controlled trial in adults with cystic fibrosis

Individuals with cystic fibrosis (CF) often incur damage to pancreatic tissue due to a dysfunctional cystic fibrosis transmembrane conductance regulator (CFTR) protein, leading to altered chloride transport on epithelial surfaces and subsequent development of cystic fibrosis-related diabetes (CFRD). Vitamin D deficiency has been associated with the development of CFRD. This was a secondary analysis of a multicenter, double-blind, randomized, placebo-controlled study in adults with CF hospitalized for an acute pulmonary exacerbation (APE), known as the Vitamin D for the Immune System in Cystic Fibrosis (DISC) trial (NCT01426256). This was a pre-planned secondary analysis to examine if a high-dose bolus of cholecalciferol (vitamin D3) can mitigate declined glucose tolerance commonly associated with an acute pulmonary exacerbation (APE). Glycemic control was assessed by hemoglobin A1c (HbA1c) and fasting blood glucose levels before and 12 months after the study intervention. Within 72 hours of hospital admission, participants were randomly assigned to a single dose of oral vitamin D3 (250,000 IU) or placebo, and subsequently, received 50,000 IU of vitamin D3 or placebo every other week, beginning at month 3 and ending on month 12. Forty-nine of the 91 participants in the parent study were eligible for the secondary analysis. There were no differences in 12-month changes in HbA1c or fasting blood glucose in participants randomized to vitamin D or placebo. A high-dose bolus of vitamin D3 followed by maintenance vitamin D3 supplementation did not improve glycemic control in patients with CF after an APE.

Calcium, Phosphorus, and Vitamin D Levels in a Series of Cystic Fibrosis Patients: A Cross-Sectional Study

Cystic fibrosis (CF) is a monogenic disease with different types of mutations that mainly affect the respiratory-digestive system. Calcium (Ca), phosphorus (P), and vitamin D (Vit-D) are essential nutrients for maintaining adequate growth and development, as well as key components in crucial metabolic pathways. Proper diagnosis, treatment, and response are decisive components of precision medicine. Therefore, we conducted a cross-sectional study to evaluate Ca, P, and Vit-D levels along with health and nutritional indicators, regarding their non-skeletal functions, in a series of CF patients. Anthropometric and clinical evaluation, biochemical analysis, dietary survey, and respiratory and pancreatic status were performed. Even though the results showed that all patients had normal dietary and serum Ca levels, 47% of patients had deficient Vit-D intake, 53% of patients had hypovitaminosis D, 35% had insufficient Vit-D levels, 18% had hypophosphatemia, 76% had elevated alkaline phosphate levels, 29% had hypercalciuria, and 65% had hyperphosphaturia. There were no significant differences between homozygous and compound heterozygous patients. Ca, P, and Vit-D levels were associated with body mass index; body composition; physical activity; diet; growth hormones; and the immune, liver, and kidney systems. We suggest a periodically evaluation of Ca and P losses.

Vitamin D deficiency in patients with cystic fibrosis: a systematic review and meta-analysis

AIM

Vitamin D is a prominent modulator of immunity and respiratory function. It plays a vital role in respiratory diseases such as cystic fibrosis (CF). S. However, there is a dearth of information on patients with CF. The purpose of the meta-analysis is to highlight the importance of following the existing guidelines regarding maintenance of Vitamin D serum levels in patients with CF.

METHODS

The systematic search was conducted without utilizing any time or language limitations in original database from the beginning until March 2022. The meta-analysis was performed using a random-effects model. Heterogeneity was determined by I2 statistics and Cochrane Q test.

RESULTS

Pooled analysis using the random-effects model of the 8 case-control studies with 13 effect sizes revealed that the serum 25-OH-vitamin D in participants with cystic fibrosis was significantly lower than controls in pediatrics and adolescences (WMD: - 3.41 ng/ml, 95% CI - 5.02, - 1.80, p =  < 0.001) and adults (WMD: - 2.60 ng/ml, 95% CI - 4.32, - 0.89, p = 0.003). Based on data from 12 studies (21 effect sizes) with a total of 1622 participants, the prevalence of vitamin D levels of 20-30 ng/ml in CF patients was 36% among pediatrics/adolescents and 63% among adults. In addition, 27% of pediatric/adolescent CF patients and 35% of adult CF patients had vitamin D levels of below 20 ng/ml.

CONCLUSIONS

As a result, according to the existing guidelines, our results proved the need to pay attention to the level of vitamin D in these patients.

Vitamin D and Prebiotics for Intestinal Health in Cystic Fibrosis: Rationale and design for a randomized, placebo-controlled, double-blind, 2 × 2 trial of administration of prebiotics and cholecalciferol (vitamin D3) (Pre-D Trial) in adults with cystic fibrosis

Individuals with cystic fibrosis (CF) have dysfunctional intestinal microbiota and increased gastrointestinal (GI) inflammation also known as GI dysbiosis. It is hypothesized that administration of high-dose cholecalciferol (vitamin D3) together with a prebiotic (inulin) will be effective, and possibly additive or synergistic, in reducing CF-related GI dysbiosis and improving intestinal functions. Thus, a 2 × 2 factorial design, placebo-controlled, double-blind, clinical trial was proposed to test this hypothesis. Forty adult participants with CF will be block-randomized into one of four groups: 1) high-dose oral vitamin D3 (50,000 IU weekly) plus oral prebiotic placebo daily; 2) oral prebiotic (12 g inulin daily) plus oral placebo vitamin D3 weekly; 3) combined oral vitamin D3 weekly and oral prebiotic inulin daily; and 4) oral vitamin D3 placebo weekly and oral prebiotic placebo. The primary endpoints will include 12-week changes in the reduced relative abundance of gammaproteobacteria, and gut microbiota richness and diversity before and after the intervention. This clinical study will examine whether vitamin D3 with or without prebiotics will improve intestinal health and reduce GI dysbiosis, which in turn, should improve health outcomes and quality of life of patients with CF.

Maternal vitamin D in pregnancy and infant's gut microbiota: a systematic review

Background

An infant's gut microbiome plays a vital role in their health, and various factors can impact their gut microbiota composition. This review aimed to summarize the current knowledge regarding the associations between maternal prenatal supplementation with vitamin D and the composition of infants' gut microbiota.

Method

A comprehensive systematic search was done on Web of Science, Scopus, PubMed, ScienceDirect, and Google Scholar databases without date restrictions until December 2022 using relevant keywords. All relevant original articles in English were eligible for the present review.

Results

Eight articles (two mice, three randomized clinical trials, and three cohort studies) were included in this review. The included mice studies reported that maternal prenatal vitamin D supplementation significantly affects the offspring's gut microbiome composition (such as enhancing the abundance of colonic Bacteroides). Moreover, the included cohort studies revealed a significant association between maternal supplementation with vitamin D during pregnancy and the infant's gut microbiome. However, one-third of clinical trials indicated that vitamin D levels in utero could influence the colonization of the microbial community in the infant's gut.

Conclusion

The findings of this review revealed that maternal vitamin D supplementation during pregnancy was linked to an infant's gut microbiome and could impact their gut microbiota composition. However, more studies are warranted to confirm these results.

Hope in Every Breath: Navigating the Therapeutic Landscape of Cystic Fibrosis

Cystic fibrosis (CF) has long posed a complex challenge to medical science. Still, the tides are turning with remarkable progress in prognosis and demographics, thanks to cutting-edge medical management and treatment breakthroughs. It affects multiple systems, necessitating a comprehensive approach to its management. This article thoroughly reviews the latest advancements in CF treatment across three key areas: respiratory care, infection prevention, and pharmacological management. In respiratory care, emphasis is placed on airway clearance therapies and nebulized saline, while infection prevention strategies encompass hand hygiene, respiratory etiquette, and environmental cleaning and disinfection. Pharmacological management explores pancreatic enzyme replacement therapy (PERT), antimicrobial treatments, cystic fibrosis transmembrane regulator (CFTR) modulators, and promising gene therapies. Patient education and support are highlighted as crucial components of effective CF management, while mental health assessments are emphasized due to CF patients' susceptibility to anxiety and depression. This review highlights the tremendous progress made in the management of CF. Integrating early detection, infection prevention, pharmacological interventions, gene therapy, and patient support is revolutionizing the care and quality of life for individuals with CF.

Relationship of Vitamin D level with insulin dosage required based on insulin therapy protocol

The deficiency of vitamin D amongst Iranian people is high and also is related on hyperglycemia. This study aims to evaluate the association of vitamin D levels with the required dose of insulin prescribed based on an insulin therapy protocol in critical condition patients admitted to intensive care unit (ICU), in an investigation based in Iran. This cross-sectional study was performed on patients who required insulin due to hyperglycemia. The relationship between serum vitamin D level and the required dose of insulin prescribed based on insulin therapy protocol in this group of patients was investigated. A total of 172 patients with a mean age of 46.93 ± 31.9 years were included in this study. Across the included participants, 78.8% of patients had vitamin D deficiency, 11.9% had insufficient vitamin D and 9.3% had normal vitamin D levels. There was a significant difference in mean blood sugar between the vitamin D deficiency group and the normal group. Vitamin D levels were also significantly higher in men than women. Furthermore, the HbA1C hemoglobin level in patients with Vitamin D deficiency was significantly higher compared to the group with normal levels of vitamin D. Our findings suggest that decreased vitamin D is associated with increased blood sugar and insulin requirements in patients admitted to ICU. Women are at a higher risk for vitamin D deficiency. We hope that these findings may help inform relevant treatment strategies.

Nutritional Care in Children with Cystic Fibrosis

Patients with cystic fibrosis (CF) are prone to malnutrition and growth failure, mostly due to malabsorption caused by the derangement in the chloride transport across epithelial surfaces. Thus, optimal nutritional care and support should be an integral part of the management of the disease, with the aim of ameliorating clinical outcomes and life expectancy. In this report, we analyzed the nutrition support across the different ages, in patients with CF, with a focus on the relationships with growth, nutritional status, disease outcomes and the use of the CF transmembrane conductance regulator (CFTR) modulators. The nutrition support goal in CF care should begin as early as possible after diagnosis and include the achievement of an optimal nutritional status to support the growth stages and puberty development in children, that will further support the maintenance of an optimal nutritional status in adult life. The cornerstone of nutrition in patients with CF is a high calorie, high-fat diet, in conjunction with a better control of malabsorption due to pancreatic enzyme replacement therapy, and attention to the adequate supplementation of fat-soluble vitamins. When the oral caloric intake is not enough for reaching the anthropometric nutritional goals, supplemental enteral feeding should be initiated to improve growth and the nutritional status. In the last decade, the therapeutic possibilities towards CF have grown in a consistent way. The positive effects of CFTR modulators on nutritional status mainly consist in the improvement in weight gain and BMI, both in children and adults, and in an amelioration in terms of the pulmonary function and reduction of exacerbations. Several challenges need to be overcome with the development of new drugs, to transform CF from a fatal disease to a treatable chronic disease with specialized multidisciplinary care.

XCHT alleviates the pancreatic fibrosis via VDR/NLRP3 signaling pathway in a mouse model of CP

ETHNOPHARMACOLOGICAL RELEVANCE

Xiao Chai Hu Tang (XCHT) derived from the classic medical book Shang Han Lun (Treatise on Febrile Diseases) in the Eastern Han Dynasty, which has been widely used in China and other Asian countries for the treatment of inflammation and fibrosis of chronic pancreatitis (CP), but the therapeutic mechanism of XCHT in pancreatic fibrosis remains unclear.

AIM OF THE STUDY

This study aimed to evaluate the intervention effects and explore pharmacological mechanism of XCHT on inflammation and fibrosis in cerulein-induced CP model.

MATERIALS AND METHODS

Fifty male C57BL/6 mice were randomly divided into five main groups, 10 animals in each: Control, CP model (50 μg/kg cerulein), high dose XCHT-treated CP group (60 g/kg XCHT), medium dose XCHT-treated CP group (30 g/kg XCHT) and low dose XCHT-treated CP group (15 g/kg XCHT). Different doses of XCHT were given to mice by gavage twice a day for 2 weeks after the CP model induction. Pancreatic tissues were harvested and the pancreatic inflammation and fibrosis were evaluated by histological score, Sirius red staining, and alpha-smooth muscle actin (α-SMA) immunohistochemical staining. ELISA, IHC and RT-qPCR were performed to detect the expression of Vitamin D₃ (VD₃) and Vitamin D receptor (VDR) in serum and pancreatic tissues, respectively. The expressions of NLRP3 inflammasome related genes and molecules were assayed by WB, IHC and RT-qPCR.

RESULTS

The pathohistological results demonstrated that XCHT markedly inhibited the fibrosis and chronic inflammation of cerulein-induced CP, indicated by reduction of collagen I, collagen III, α-SMA, and NLRP3 expressions. XCHT significantly increased VD₃ and VDR expression while reduced the pancreatic NLRP3 expression. Correspondingly, XCHT decreased the levels of NLRP3 downstream targets IL-1β, TNF-α and IL-6.

CONCLUSIONS

These results revealed that XCHT suppressed the pancreatic fibrosis and chronic inflammation in cerulein-induced CP model by enhancing the VD₃/VDR expression and inhibiting the secretion of NLRP3-assoicated inflammatory factors.

Maternal vitamin D deficiency aggravates the dysbiosis of gut microbiota by affecting intestinal barrier function and inflammation in obese male offspring mice

OBJECTIVES

The colonization of gut microbiota during early life may play a critical role in the progression of metabolic syndrome in adulthood. Targeting gut-based genes in the barrier function, inflammation, and lipid transportation are potential therapies for obesity. Therefore, this study focused on whether maternal deficient vitamin D (VD) intake could aggravate the dysbiosis of gut microbiota by affecting the expressions of these genes in the ileum and colon of obese male offspring mice.

METHODS

Four-week-old female C57 BL/6 J mice were fed normal (VD-C) or VD-deficient (VD-D) reproductive diets throughout pregnancy and lactation (n = 15/group). Weaning male pups (n = 10/group) were fed either a high-fat (HFD; VD-C-HFD, VD-D-HFD) or normal-fat diet (control) for 16 wk. All biologic samples were obtained after the mice were anesthetized by cervical dislocation. Subsequently, the compositions of the gut microbiota in cecal contents were analyzed using 16 S ribosomal RNA sequencing. Messenger RNA expression in the ileum and colon was determined using real-time reverse transcription-polymerase chain reaction. The distributions of ZO-1 and Claudin-1 were determined using immunohistochemistry testing.

RESULTS

Maternal deficient VD intake significantly aggravated the dysbiosis of gut microbiota persisting into adulthood from phylum to genus levels in the cecal contents among obese male offspring mice. This aggravation led to significantly depleted Bacteroidetes and Verrucomicrobia (Akkermansia, Alliprevotella, and Bacteroides), with higher relative abundance of Firmicutes (Lactobacillus, Lachnoclostridium, Romboutsia, and Ruminiclostridium_9) and Firmicutes/Bacteroidetes. The gene expressions of proinflammatory cytokines (Ccl2, Ccl4 and interleukin-1β) and lipid transportation molecules (Ffar3, Fabp4, and Fabp1) were higher, and the levels of intestinal barrier function (Occludin, ZO-1, and Claudin-1) were lower in the VD-D-HFD group than those in the VD-C-HFD group. Furthermore, there were significant correlations between the dysbiosis of intestinal microbials and expressions of genes related to barrier function, inflammation, and lipid transportation in the ileum and/or colon.

CONCLUSIONS

Maternal VD deficiency during pregnancy and lactation could aggravate the dysbiosis of gut microbiota to affect the progression of obesity among male offspring, which might be regulated by genes associated with barrier function, inflammation, and lipid transportation. So early life appropriate VD intake could play a significant role in preventing later obesity.

Changes in Metabolic Parameters in Patients with Diabetic Kidney Disease Depending on the Status of D3

BACKGROUND

Type 2 diabetes is a metabolic disease characterized by hyperglycemia as a result of insulin resistance and decreased insulin secretion. A relatively large number of patients with this type of diabetes have abdominal obesity, which also affects insulin resistance development. Chronic hyperglycemia can lead to damage and dysfunction of various organs, and a striking example is diabetic nephropathy. Diabetic nephropathy is a specific kind of kidney damage that occurs due to complications of diabetes and is accompanied by the formation of diffuse or nodular glomerulosclerosis, which can lead to terminal renal failure and requires immediate substitution through renal therapy or renal transplantation. Diabetic nephropathy is diagnosed with albuminuria and a decrease in the rate of glomerular filtration.

METHODS

This review was based on a literature search for the most important evidence of vitamin D as a possible method of prevention for obesity, type 2 diabetes, and diabetic nephropathy. Collected published articles were summarized according to their overall themes.

RESULTS

In this review, we considered vitamin D as a possible method of treatment for type 2 diabetes, as well as its complications, including diabetic nephropathy.

CONCLUSION

Studies show that vitamin D inhibits the renin-angiotensin-aldosterone system, resulting in improved renal function in diabetic nephropathy. Vitamin D also has antiinflammatory, antiproliferative, and anti-metastatic effects, which improve endothelial function.

The Crosstalk between Vitamin D and Pediatric Digestive Disorders

Vitamin D is a cyclopentane polyhydrophenanthrene compound involved mainly in bone health and calcium metabolism but also autophagy, modulation of the gut microbiota, cell proliferation, immune functions and intestinal barrier integrity. The sources of vitamin D include sunlight, diet and vitamin D supplements. Vitamin D3, the most effective vitamin D isoform is produced in the human epidermis as a result of sunlight exposure. Vitamin D undergoes two hydroxylation reactions in the liver and kidney to reach its active form, 1,25-dihydroxyvitamin D. Recent studies highlighted a complex spectrum of roles regarding the wellbeing of the gastrointestinal tract. Based on its antimicrobial effect, it was recently indicated that vitamin D supplementation in addition to standard eradication therapy might enhance H. pylori eradication rates. Moreover, it was suggested that low levels of vitamin D might also be involved in the acquisition of H. pylori infection. In terms of celiac disease, the negative effects of vitamin D deficiency might begin even during intrauterine life in the setting of maternal deficiency. Moreover, vitamin D is strongly related to the integrity of the gut barrier, which represents the core of the pathophysiology of celiac disease onset, in addition to being correlated with the histological findings of disease severity. The relationship between vitamin D and cystic fibrosis is supported by the involvement of this micronutrient in preserving lung function by clearing airway inflammation and preventing pathogen airway colonization. Moreover, this micronutrient might exert anticatabolic effects in CF patients. Inflammatory bowel disease patients also experience major benefits if they have a sufficient level of circulating vitamin D, proving its involvement in both induction and remission in these patients. The findings regarding the relationship between vitamin D, food allergies, diarrhea and constipation remain controversial, but vitamin D levels should be monitored in these patients in order to avoid hypo- and hypervitaminosis. Further studies are required to fill the remaining gaps in term of the complex impact of vitamin D on gastrointestinal homeostasis.

Correlation of Gut Microbiota, Vitamin D Status, and Pulmonary Function Tests in Children With Cystic Fibrosis

Background

Children with cystic fibrosis (CF) are expected to have suboptimal serum vitamin D status and altered gut microbiota. The altered gut microbiota is hypothesized to have a pro-inflammatory effect that further complicates the existing respiratory inflammation. Emerging evidence suggests an association between vitamin D and gut microbiota. The aim of this study was to assess the relationships between 25-hydroxyvitamin D [25(OH)D] status, pulmonary function, and fecal bacteria in children with CF.

Methods

In this cross-sectional study, a total of 35 children with CF (8.7 ± 2.83 years) and 24 controls without CF (9 ± 2.7 years) were included in this study. Serum 25(OH)D status was measured using the Elecsys vitamin D total II assay. In the CF group, gut microbiota composition was assessed using real-time PCR analysis. Pulmonary function tests (PFTs) were measured using spirometry. Comparisons between the CF and non-CF controls were conducted using the independent sample t-test. In the CF group, one-way analysis of variance (ANOVA) was used to assess differences in PFTs and gut microbiota composition across the three vitamin D subgroups. The correlations between 25(OH)D status and PFTs, or gut microbiota composition, and PFTs with gut microbiota composition were analyzed using the Pearson's correlation coefficient test.

Results

Children with CF had significantly lower serum 25(OH)D levels compared with children without CF (44.3 ± 22.4 vs. 59 ± 25.5, respectively, P = 0.026). Children with CF with optimal serum 25(OH)D level had significantly higher levels of Bacteroidetes, Firmicutes, and total bacteria (P = 0.007, P = 0.007, and P = 0.022, respectively). The level of Firmicutes was found to be significantly higher in mild forced expiratory volume in 1 s (FEV1) compared with moderate FEV1 (P = 0.032), whereas the level of the other bacteria species was comparable across FEV1 severity groups.

Conclusion

Our findings may encourage studies that target and modify gut microbiota to potentially achieve better outcomes in terms of respiratory function in CF.

Lung-kidney interactions and their role in chronic kidney disease-associated pulmonary diseases

Chronic illnesses rarely present in a vacuum, devoid of other complications, and chronic kidney disease is hardly an exception. Comorbidities associated with chronic kidney disease lead to faster disease progression, expedited dialysis dependency, and a higher mortality rate. Although chronic kidney disease is most commonly accompanied by cardiovascular diseases and diabetes, there is clear cross talk between the lungs and kidneys pH balance, phosphate metabolism, and immune system regulation. Our present understanding of the exact underlying mechanisms that contribute to chronic kidney disease-related pulmonary disease is poor. This review summarizes the current research on kidney-pulmonary interorgan cross talk in the context of chronic kidney disease, highlighting various acute and chronic pulmonary diseases that lead to further complications in patient care. Treatment options for patients presenting with chronic kidney disease and lung disease are explored by assessing activated molecular pathways and the body's compensatory response mechanisms following homeostatic imbalance. Understanding the link between the lungs and kidneys will potentially improve health outcomes for patients and guide healthcare professionals to better understand how and when to treat each of the pulmonary comorbidities that can present with chronic kidney disease.

Vitamin D Attenuates Airway Inflammation in Asthmatic Guinea Pigs Using Mammalian Target of Rapamycin-Mediated Autophagy

The purpose of this experiment is to find out the function of Vitamin D (VD) in airway inflammation in asthmatic guinea pigs by regulating mammalian target of rapamycin (mTOR)-mediated autophagy. A total of 40 male guinea pigs were randomly assigned into the Con group, the ovalbumin (OVA)-sensitized group, the VD group, the VD + dimethyl sulfoxide group, and the VD + rapamycin (mTOR inhibitor) group. Then, serum from all groups was harvested for the measurement of immunoglobulin E (IgE), interleukin (IL)-4, and IL-5 levels. Next, bronchoalveolar lavage fluid was collected for cell counting. Moreover, lung tissues were extracted to assess levels of p-mTOR and autophagy factors (LC3B, Beclin1, Atg5, and P62). Compared with the Con group, the OVA group showed elevated levels of IgE, IL-4, and IL-5, increased contents of eosinophils, neutrophil, and lymphocytes, and declined monocytes. And the VD group improved inflammatory reactions in the guinea pigs. Besides, the OVA group showed lower levels of p-mTOR and P62 and higher autophagy levels than the Con group, while the VD group had opposite results. Rapamycin annulled the suppressive role of VD to airway inflammation in asthmatic guinea pigs. VD might inhibit OVA-induced airway inflammation by inducing mTOR activation and downregulating autophagy in asthmatic guinea pigs.

Vitamins A, D, E status as related to supplementation and lung disease markers in young children with cystic fibrosis

BACKGROUND

The variable response to fat-soluble vitamin supplementation in young children with cystic fibrosis (CF), and factors contributing to this variability, remain under-investigated.

OBJECTIVE

To determine if recommended supplement doses normalize serum vitamins A (retinol), D (25-hydroxy-vitamin D, 25OHD), and E (α-tocopherol), and identify factors predictive of achieving sufficiency, in children with CF in the first 3 years of life.

DESIGN

We studied 144 infants born during 2012-2017 and diagnosed with CF through newborn screening. Serum retinol, 25OHD, α-tocopherol and plasma cytokines interleukin (IL)-6, IL-8, IL-10, and tumor necrosis factor (TNF)-α were measured in early infancy and yearly thereafter. Vitamin supplement intakes and respiratory microbiology were assessed every 1-2 months in infancy and quarterly thereafter.

RESULTS

The prevalence of vitamin D insufficiency (<30 ng/ml) at all ages combined was significantly higher (22%) compared to vitamin A (<200 ng/ml, 3%) and vitamin E (<5 µg/ml, 5%). All children were vitamin A sufficient by age 2 years. Vitamin E insufficiency was rare. Only 42% were early responders of vitamin D and 17% remain insufficient despite high supplement intakes. IL-6 was positively correlated, while IL-8, IL-10, and TNF-α were negatively correlated, with retinol and 25OHD. Multiple regression analysis revealed that supplement dose, season, α-tocopherol, pancreatic insufficiency, respiratory infections and IL-10 were significant predictors of 25OHD.

CONCLUSION

Diagnosis through newborn screening coupled with supplementation normalized serum retinol and α-tocopherol in almost all infants with CF by age 3 years. However, response to vitamin D supplements in young children with CF occurred later and variably despite early and sustained supplementation.

Vitamin D3 alleviates cigarette smoke extract‑mediated epithelial‑mesenchymal transition and fibrogenesis by upregulating CC16 expression in bronchial epithelial cells

Vitamin D3 supplementation has been previously reported to inhibit the occurrence and development of chronic obstructive pulmonary disease (COPD). However, the underlying mechanism remains unclear. Epithelial-mesenchymal transition (EMT) and fibrogenesis have been associated with the development of COPD. The aim of the present study was to investigate the potential effects and mechanism of vitamin D3 in an in vitro model of cigarette smoke (CS)-induced EMT and fibrosis, with specific focus on the role of club cell protein 16 (CC16). CS extract (CSE) at different concentrations (5, 10 and 20%) was used to treat 16-HBE cells to induce EMT and fibrogenesis following which they were treated with vitamin D3. Subsequently, the 20% CSE group was selected for further experiments, where 16-HBE cells were divided into the following five groups: The control group; the CSE group; the low-dose vitamin D3 group (250 nM); the medium-dose vitamin D3 group (500 nM); and the high-dose vitamin D3 group (1,000 nM). Western blot analysis was used to detect the protein expression levels of the EMT-related proteins E-cadherin, N-cadherin, Slug and α-SMA, fibrogenesis-related proteins collagen Ⅳ and fibronectin 1, proteins involved in the TGF-β1/SMAD3 signaling pathway and CC16. Immunofluorescence was used to measure the protein expression levels of E-cadherin, N-cadherin and collagen Ⅳ. Specific CC16 knockdown was performed using short hairpin RNA transfection to investigate the role of CC16. The results of the present study found that vitamin D3 could increase the protein expression level of CC16 to inhibit the activation of the TGF-β1/SMAD3 signaling pathway; thereby reducing the 20% increase in CSE-induced EMT- and fibrogenesis-related protein expression levels. Following CC16 knockdown, the inhibitory effects of vitamin D3 on EMT- and fibrogenesis-related protein expression were partially reversed. To conclude, these results suggest that vitamin D3 can inhibit the protein expression levels of EMT- and fibrogenesis-related proteins induced by CSE, at least partially through the function of CC16. These findings are expected to provide novel theoretical foundations and ideas for the pathogenesis and treatment of COPD.

Utilization of the Healthy Eating Index in Cystic Fibrosis

(1) Background: Malnutrition has been a hallmark of cystic fibrosis (CF) for some time, and improved nutritional status is associated with improved outcomes. While individuals with CF historically required higher caloric intake than the general population, new CF therapies and improved health in this population suggest decreased metabolic demand and prevalence of overweight and obesity have increased. This study aimed to (a) examine diet quality in a population of young adults with CF using the Healthy Eating Index, a measure of diet quality in accordance with the U.S. Dietary Guidelines for Americans and (b) evaluate and describe how subcomponents of the HEI might apply to individuals with CF (2) Methods: 3-day dietary recalls from healthy adolescents and young adults with CF were obtained and scored based on the Healthy Eating Index (3) Results: Dietary recalls from 26 (14M/12F) adolescents and young adults with CF (ages 16–23), were obtained. Individuals with CF had significantly lower HEI scores than the general population and lower individual component scores for total vegetables, greens and beans, total fruits, whole fruits, total protein, seafood and plant protein and sodium (p values < 0.01 for all). (4) Conclusion: Dietary quality was poor in these healthy adolescents and young adults with CF. Given the increased prevalence of overweight and obesity in CF, updated dietary guidance is urgently needed for this population. The Healthy Eating Index may be a valuable tool for evaluating dietary quality in CF.

Impact of vitamin D status on CF and non-CF bronchiectasis outcomes

Background

Vitamin D deficiency occurs frequently in cystic fibrosis (CF) and non-CF bronchiectasis patients. Yet, few studies have assessed the impact of vitamin D status on the clinical outcomes in pediatric bronchiectasis. This study is designed to assess vitamin D level and determine its effect on exacerbations, bacterial colonization, and lung function in pediatric patients with CF and non-CF bronchiectasis.

Results

This cross-sectional case-control study assessing vitamin D level was performed in a total of sixty cases under the age of 18 years—forty cases with CF and non-CF bronchiectasis and twenty age- and sex-matched healthy controls. Associations between serum vitamin D and clinical and laboratory parameters were assessed in the patient groups. Vitamin D deficiency was more prevalent among CF and non-CF bronchiectasis patients (75%, 45%) compared to controls (10%) (P < 0.001). In addition, vitamin D deficiency was associated with more frequent and severe pulmonary exacerbations (66.7%, 46.7%) (P=0.033, < 0.001), chronic Pseudomonas infection (80%) (P=0.060) among CF patients, and with lower FEV1 (66%) (P= 0.071) among non-CF bronchiectasis. Moreover, a cutoff value of vitamin D level equal or less than 22.5 ng/ml was accurate in differentiating moderate from mild pulmonary exacerbations in both patients’ groups (AUC=0.809) (p=0.004).

Conclusions

Vitamin D deficiency is not uncommon in both CF and non-CF bronchiectasis. In this population, vitamin D deficiency is associated with more frequent pulmonary exacerbations, chronic Pseudomonas infection, and worse lung function.

The Effects of RBP4 and Vitamin D on the Proliferation and Migration of Vascular Smooth Muscle Cells via the JAK2/STAT3 Signaling Pathway

Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are one of the main causes of the development of diabetic atherosclerotic process. The aim of our study was to assess the role of RBP4 in the proliferation and migration of VSMCs and the inhibitory effect of vitamin D on the mechanisms. In an in vivo experiment, rats were randomly classified into 6 groups: the control group, diabetic rats, diabetic atherosclerotic rats (diabetic rats intraperitoneally injected with RBP4), diabetic atherosclerotic rats treated with 0.075 μg kg⁻¹ d⁻¹ vitamin D, 0.15 μg kg⁻¹ d⁻¹ vitamin D and 0.3 μg kg⁻¹ d⁻¹ vitamin D. We found that the levels of JAK2, STAT3, cylinD1, and Bcl-2 were increased in diabetic atherosclerotic rats, and these increases were improved after vitamin D supplementation. Furthermore, to investigate the underlying molecular mechanisms, cells were cultured with glucose in the presence of RBP4 and the absence of RBP4, respectively, and vitamin D of different concentrations and different intervention times was simultaneously adopted. The proliferation and migration of VSMCs was enhanced and the levels of JAK2, STAT3, cyclinD1, and Bcl-2 were increased in the cells transfected with RBP4 overexpression plasmid. Moreover, vitamin D supplementation was detected to lower the expressions of JAK2, STAT3, cyclinD1, and Bcl-2 and inhibit the abnormal proliferation of VSMCs caused by the RBP4/JAK2/STAT3 signaling pathway. RBP4 can promote the proliferation and migration of VSMCs and contributes to the development of diabetic macroangiopathy via regulating the JAK2/STAT3 signaling pathway. This mechanism of RBP4 can be inhibited by vitamin D supplementation.

Current Overview on Therapeutic Potential of Vitamin D in Inflammatory Lung Diseases

Inflammatory lung disorders (ILDs) are one of the world’s major reasons for fatalities and sickness, impacting millions of individuals of all ages and constituting a severe and pervasive health hazard. Asthma, lung cancer, bronchiectasis, pulmonary fibrosis acute respiratory distress syndrome, and COPD all include inflammation as a significant component. Microbe invasions, as well as the damage and even death of host cells, can cause and sustain inflammation. To counteract the negative consequences of irritants, the airways are equipped with cellular and host defense immunological systems that block the cellular entrance of these irritants or eliminate them from airway regions by triggering the immune system. Failure to activate the host defense system will trigger chronic inflammatory cataracts, leading to permanent lung damage. This damage makes the lungs more susceptible to various respiratory diseases. There are certain restrictions of the available therapy for lung illnesses. Vitamins are nutritional molecules that are required for optimal health but are not produced by the human body. Cholecalciferol (Vitamin D) is classified as a vitamin, although it is a hormone. Vitamin D is thought to perform a function in bone and calcium homeostasis. Recent research has found that vitamin D can perform a variety of cellular processes, including cellular proliferation; differentiation; wound repair; healing; and regulatory systems, such as the immune response, immunological, and inflammation. The actions of vitamin D on inflammatory cells are dissected in this review, as well as their clinical significance in respiratory illnesses.

A Clinician’s guide to vitamin D supplementation for patients with cystic fibrosis

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Vitamin D deficiency is multifactorial in the cystic fibrosis population.

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Vitamin D deficiency can adversely affect multiple organ systems in the cystic fibrosis population.

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In the cystic fibrosis population in the United States, we aim to treat to serum 25-hydroxyvitamin D levels over 30 ng/ml.

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Cholecalciferol is used in preference to ergocalciferol.

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Daily or once weekly dosing regimens are chosen according to patient preference and compliance.

Vitamin D deficiency is common in the general population, and even more so in patients with cystic fibrosis. Deficiency is exacerbated in cystic fibrosis patients because of a myriad of causes including malabsorption, decreased fat mass, reduced 25-hydroxylation of vitamin D, reduced exposure to sunlight, decreased vitamin D binding protein, and exposure to drugs that increase catabolism. In turn, vitamin D deficiency can contribute to poor bone health. Additionally, it may contribute to pulmonary decline in the form of worsening pulmonary function, increased colonization with pathogens, and increased pulmonary exacerbation. Because vitamin D deficiency is correlated with negative clinical effects in multiple organ systems of patients with cystic fibrosis, it is important to screen for and treat deficiency in these patients. The Cystic Fibrosis Foundation has issued guidelines for the treatment of vitamin D deficiency, targeting serum levels of 25-hydroxyvitamin D of at least 30 ng/ml. The guidelines offer age-specific escalating dose regimens depending on serum vitamin D levels, with monitoring at 12- week intervals after changing therapy. They address the literature on alternative vitamin D sources, such as UV lamps, ideal formulations (cholecalciferol in preference to ergocalciferol), and optimal vehicles of administration. Despite these detailed recommendations, most centers are still unable to achieve in-target serum vitamin D levels for many of their patients. Future research examining ideal treatment regimens to achieve serum targets and maximize clinical effects are needed. Moreover, it is unknown whether vitamin D sufficiency will be easier to achieve on new triple therapy cystic fibrosis drug combinations, and how these drugs will contribute to vitamin D-related clinical outcomes.

Vitamin D Status and Risk of Cystic Fibrosis-Related Diabetes: A Retrospective Single Center Cohort Study

Objective: Cystic fibrosis-related diabetes (CFRD) affects up to half of the people with cystic fibrosis (CF) by adulthood. CFRD is primarily caused by pancreatic dysfunction that leads to insufficient insulin release and/or insulin resistance. Exocrine pancreatic insufficiency in people with CF is associated with fat-soluble vitamin malabsorption, including vitamins A, D, E, and K. This study examined the relationship between vitamin D status, assessed by serum 25-hydroxyvitamin D (25(OH)D), and the development of CF-related diabetes (CFRD) in adults with CF. Methods: This was a retrospective cohort study of adults seen at a single CF center. The data were extracted from the electronic medical records and the Emory Clinical Data Warehouse, a data repository of health information from patients seen at Emory Healthcare. We collected age, race, the first recorded serum 25-hydroxyvitamin D (25(OH)D) concentration, body mass index (BMI), and onset of diabetes diagnosis. Log-rank (Mantel–Cox) tests were used to compare the relative risk of CFRD onset in the subjects with stratified vitamin D status and weight status. A sub-group analysis using chi-square tests assessed the independence between vitamin D deficiency and CFRD risk factors, including gender and CF mutation types (homozygous or heterozygous for F508del, or others). Unpaired t-tests were also used to compare the BMI values and serum 25(OH)D between the CF adults based on the CFRD development. Results: This study included 253 subjects with a mean age of 27.1 years (±9.0), a mean follow-up time period of 1917.1 (±1394.5) days, and a mean serum 25(OH)D concentration of 31.8 ng/mL (±14.0). The majority (52.6%) of the subjects developed CFRD during the study period. Vitamin D deficiency (defined as 25(OH)D < 20 ng/mL) was present in 25.3% of the subjects. Close to two thirds (64.1%) of the subjects with vitamin D deficiency developed CFRD during the study. Vitamin D deficiency increased the risk of developing CFRD (chi-square, p = 0.03) during the course of the study. The time to the onset of CFRD stratified by vitamin D status was also significant (25(OH)D < 20 ng/mL vs. 25(OH)D ≥ 20 ng/mL) (95% CI: 1.2, 2.7, p < 0.0078). Conclusion: Our findings support the hypothesis that adults with CF and vitamin D deficiency are at a higher risk of developing CFRD and are at risk for earlier CFRD onset. The maintenance of a serum 25(OH)D concentration above 20 ng/mL may decrease the risk of progression to CFRD.

Analysis of multiple gene co-expression networks to discover interactions favoring CFTR biogenesis and ΔF508-CFTR rescue

BACKGROUND

We previously reported that expression of a miR-138 mimic or knockdown of SIN3A in primary cultures of cystic fibrosis (CF) airway epithelia increased ΔF508-CFTR mRNA and protein levels, and partially restored CFTR-dependent chloride transport. Global mRNA transcript profiling in ΔF508-CFBE cells treated with miR-138 mimic or SIN3A siRNA identified two genes, SYVN1 and NEDD8, whose inhibition significantly increased ΔF508-CFTR trafficking, maturation, and function. Little is known regarding the dynamic changes in the CFTR gene network during such rescue events. We hypothesized that analysis of condition-specific gene networks from transcriptomic data characterizing ΔF508-CFTR rescue could help identify dynamic gene modules associated with CFTR biogenesis.

METHODS

We applied a computational method, termed M-module, to analyze multiple gene networks, each of which exhibited differential activity compared to a baseline condition. In doing so, we identified both unique and shared gene pathways across multiple differential networks. To construct differential networks, gene expression data from CFBE cells were divided into three groups: (1) siRNA inhibition of NEDD8 and SYVN1; (2) miR-138 mimic and SIN3A siRNA; and (3) temperature (27 °C for 24 h, 40 °C for 24 h, and 27 °C for 24 h followed by 40 °C for 24 h).

RESULTS

Interrogation of individual networks (e.g., NEDD8/SYVN1 network), combinations of two networks (e.g., NEDD8/SYVN1 + temperature networks), and all three networks yielded sets of 1-modules, 2-modules, and 3-modules, respectively. Gene ontology analysis revealed significant enrichment of dynamic modules in pathways including translation, protein metabolic/catabolic processes, protein complex assembly, and endocytosis. Candidate CFTR effectors identified in the analysis included CHURC1, GZF1, and RPL15, and siRNA-mediated knockdown of these genes partially restored CFTR-dependent transepithelial chloride current to ΔF508-CFBE cells.

CONCLUSIONS

The ability of the M-module to identify dynamic modules involved in ΔF508 rescue provides a novel approach for studying CFTR biogenesis and identifying candidate suppressors of ΔF508.

The Impact of Vegan and Vegetarian Diets on Physical Performance and Molecular Signaling in Skeletal Muscle

Muscular adaptations can be triggered by exercise and diet. As vegan and vegetarian diets differ in nutrient composition compared to an omnivorous diet, a change in dietary regimen might alter physiological responses to physical exercise and influence physical performance. Mitochondria abundance, muscle capillary density, hemoglobin concentration, endothelial function, functional heart morphology and availability of carbohydrates affect endurance performance and can be influenced by diet. Based on these factors, a vegan and vegetarian diet possesses potentially advantageous properties for endurance performance. Properties of the contractile elements, muscle protein synthesis, the neuromuscular system and phosphagen availability affect strength performance and can also be influenced by diet. However, a vegan and vegetarian diet possesses potentially disadvantageous properties for strength performance. Current research has failed to demonstrate consistent differences of performance between diets but a trend towards improved performance after vegetarian and vegan diets for both endurance and strength exercise has been shown. Importantly, diet alters molecular signaling via leucine, creatine, DHA and EPA that directly modulates skeletal muscle adaptation. By changing the gut microbiome, diet can modulate signaling through the production of SFCA.

Cystic fibrosis improves COVID-19 survival and provides clues for treatment of SARS-CoV-2

Systemic pools of ATP are elevated in individuals homozygous for cystic fibrosis (CF) as evidenced by elevated blood and plasma ATP levels. This elevated ATP level seems to provide benefit in the presence of advanced solid tumors (Abraham et al., Nature Medicine 2(5):593-596, 1996). We published in this journal a paper showing that IV ATP can elevate the depleted ATP pools of advanced cancer patients up to levels found in CF patients with subsequent clinical, biochemical, and quality of life (QOL) improvements (Rapaport et al., Purinergic Signalling 11(2): 251-262, 2015). We hypothesize that the elevated ATP levels seen in CF patients may be benefiting CF patients in another way: by improving their survival after contracting COVID-19. We discuss here the reasoning behind this hypothesis and suggest how these findings might be applied clinically in the general population.

Analysis of serum cytokine and protective vitamin D levels in severe cases of COVID-19

In this study, we investigated the role and relationship between the cytokine profile and protective vitamin D by measuring their serum levels in COVID‐19 intensive care unit patients with severe illnesses. A total of 74 patients were included in our study. Patients were divided into two groups. Patients in the COVID‐19 group (n = 31) and individuals without a history of serious illness or infection were used as the control group (n = 43). The serum concentrations of interleukin‐1 (IL‐1), IL‐6, IL‐10, IL‐21, and tumor necrosis factor‐α (TNF‐α) were measured by enzyme‐linked immunosorbent assays. Levels of serum vitamin D were detected with Liquid chromatography–mass spectrometry methodologies. TNF‐α, IL‐1, IL‐6, IL‐10, IL‐21, and vitamin D levels were measured in all patients. The serum cytokine levels in the COVID‐19 patient group were significantly higher (151.59 ± 56.50, 140.37 ± 64.32, 249.02 ± 62.84, 129.04 ± 31.64, and 123.58 ± 24.49, respectively) than control groups. Serum vitamin D was also significantly low (6.82 ± 3.29) in patients in the COVID‐19 group than the controls (21.96 ± 5.39). Regarding the correlation of vitamin D with cytokine levels, it was significantly variable. Our study shows that COVID‐19 patients are associated with lower serum vitamin D and higher pro‐inflammatory cytokines associated with increased virus presence. Our data provide more evidence of the anti‐inflammatory effect of vitamin D on COVID‐19 patients and the protective effects of vitamin D on risk were demonstrated.

Association between Vitamin D and Risk of Stroke: A PRISMA-Compliant Systematic Review and Meta-Analysis

BACKGROUND

Previous studies have shown inconsistent results for associations between vitamin D and risk of stroke. We gathered the existing published articles and conducted this meta-analysis with the aim to explore the association between vitamin D and risk of stroke.

METHODS

We searched for articles exploring the association between vitamin D and risk of stroke and published before April 2021 in the following databases: PubMed, Web of Science, MEDLINE, EMBASE, and Google Scholar. All statistical analyses were made using STATA 12.0 software. Q test and I2 were applied to examine heterogeneities between studies.

RESULTS

For the association between serum levels of 25(OH) vitamin D and risks of stroke, the present analysis included 20 cohort studies (including 213,276 participants) and a case-control analysis (including 13,642 participants). Additionally, the analysis included 15 studies (including 41,146 participants given vitamin D supplementation and 41,163 participants given placebo) to evaluate the influence of vitamin D supplementation on risk of stroke. Higher circulating levels of 25(OH) vitamin D were associated with a reduced risk of stroke (odds ratio/relative risk = 0.78, 95% confidence interval [CI]: 0.70-0.86, I2 = 41.5%, p = 0.025). However, the present analysis showed that vitamin D supplementation did not influence the risk of stroke (hazard ratio = 1.05, 95% CI: 0.96-1.14, I2 = 2.3%, p = 0.425).

CONCLUSIONS

Our analysis indicated that lower circulating level of vitamin D was associated with an elevated risk of stroke, but extra supplement of vitamin D failed to show benefit in decreasing the risk of stroke. Further research and study are also needed to show the role of vitamin D in relation to stroke.

Vitamin D3 levels in women and factors contributing to explain metabolic variations

The elucidated metabolism of vitamin D₃ in humans has been the support to explain the high involvement of this liposoluble vitamin in physiological functions. Clinical studies have associated levels of vitamin D₃ metabolites with several disorders. Despite this knowledge, there is a controversy regarding the estimation of deficiency and the physiological and supraphysiological levels of vitamin D₃ metabolites. The association between serum concentrations of vitamin D₃ metabolites and several potentially influential factors (namely, age and anthropometric, seasonal, spatial and metabolic factors) is analyzed in this study. For this purpose, 558 women were recruited and interviewed in several Spanish provinces before blood sampling. Serum vitamin D₃ and its metabolites were determined using an SPE-LC-MS/MS platform. The concentration range for vitamin D₃ was 1.7-21.1 nmol/L and was influenced by body mass index (BMI), waist-to-hip ratio (WHR) and seasonal period. 25-hydroxyvitamin D₃ levels were within 4.8-147.2 nmol/L and were related to WHR, season, latitude and calcium intake. The range of 24,25-dihydroxyvitamin D₃, 0.3-15.0 nmol/L, was associated to BMI, WHR, season, latitude and calcium intake. Finally, energy intake influenced the vitamin D 25-hydroxylase through the 25-hydroxyvitamin D₃/vitamin D₃ ratio, which regulates the synthesis of the circulating form. According to these results, it is worth emphasizing the relevance of all these factors to explain the variability in serum levels of vitamin D₃ and its metabolites. All these factors should be considered in future studies assessing the alteration of vitamin D₃ metabolism.

Vitamin D alleviates hypoxia/reoxygenation-induced injury of human trophoblast HTR-8 cells by activating autophagy

INTRODUCTION

Attenuation of trophoblast cell dysfunction would be beneficial for retarding pre-eclampsia (PE). Vitamin D has been reported to improve trophoblast cell function in early PE, but the mechanism involved is not fully elucidated. This study is aimed to investigate whether vitamin D alleviates trophoblast cell dysfunction via regulating autophagy.

METHODS

Human trophoblast HTR-8 cells were cultured in hypoxia/reoxygenation (H/R) condition to simulate the oxidative stress state of early PE in vitro. MTT, Transwell and tube formation assays were respectively applied to assess cell proliferation, invasion, and angiogenesis abilities. DCFH-DA staining was performed to detect cellular reactive oxygen species levels. GFP-RFP-LC3 plasmid transfection and transmission electron microscopy were subjected to monitor autophagy. Enzyme-linked immunosorbent assay and Western blot analysis were used to detect autophagy-related and pyroptosis-associated molecules.

RESULTS

H/R led to severe impairments on the bio-function of HTR-8 cells, as evidenced by the deficiency of cell proliferation, invasion, and angiogenesis abilities, and the increase of cellular ROS production. Simultaneously, H/R inhibited autophagy and triggered pyroptosis. 1,25(OH)₂D₃, the hormonally active form of vitamin D, dramatically attenuated H/R-induced trophoblast dysfunction. Also, 1,25(OH)₂D₃ activated autophagy and inhibited pyroptosis. Additionally, autophagy-enhancer rapamycin exerted similar protective effect to that of 1,25(OH)₂D₃, whereas autophagy-inhibitor 3-methyladenine blocked the protective effect of 1,25(OH)₂D₃.

DISCUSSION

The mechanism that vitamin D alleviates trophoblast cell dysfunction is associated with autophagy induction and pyroptosis inhibition.

Vitamin D status and pulmonary exacerbations in children and adolescents with cystic fibrosis: Experience from a tertiary care center

Background:

The function of Vitamin D in preventing inflammation and infection has been studied previously for different pathologies in different populations globally. Relationships between serum Vitamin D levels and its effect on pulmonary exacerbations in the cystic fibrosis (CF) population are not well studied in our part of the world. Therefore, we aimed to ascertain the Vitamin D status in pediatric and adolescent CF patients and its association with pulmonary exacerbations.

Materials and Methods:

A retrospective study was conducted at The Aga Khan University Hospital from 2015 to 2018. Patients of CF with sweat chloride value >60 mmol/l and who had at least one measurement of 25 hydroxy Vitamin D (25 OHD) were included in the study. Annual serum Vitamin D levels were documented for enrolled patients and their past 1-year data were analyzed for pulmonary exacerbations, average length of stay, and tracheal/airway colonization with organisms.

Results:

69 patients were included in the study. 28 patients (40.57%) were found to be Vitamin D deficient, 22 patients (31.88%) were Vitamin D insufficient and 19 patients (27.53%) were labeled as Vitamin D insufficient. The average number of exacerbations per year was significantly high in Vitamin D deficient group (3.71 ± 0.96) in comparison with insufficient (3.18 ± 1.09) and sufficient groups (2.26 ± 0.93) (P < 0.001).

Conclusion:

Vitamin D deficiency is related to an increased number of annual pulmonary exacerbations and pseudomonas infections.

Vitamin D and its therapeutic relevance in pulmonary diseases

Vitamin D is customarily involved in maintaining bone and calcium homeostasis. However, contemporary studies have identified the implication of vitamin D in several cellular processes including cellular proliferation, differentiation, wound healing, repair and regulatory systems inclusive of host defence, immunity, and inflammation. Multiple studies have indicated corelations between low serum levels of vitamin D, perturbed pulmonary functions and enhanced incidences of inflammatory diseases. Almost all of the pulmonary diseases including acute lung injury, cystic fibrosis, asthma, COPD, Pneumonia and Tuberculosis, all are inflammatory in nature. Studies have displayed strong inter-relations with vitamin D deficiency and progression of lung disorders; however, the underlying mechanism is still unknown. Vitamin D has emerged to possess inhibiting effects on pulmonary inflammation while exaggerating innate immune defenses by strongly influencing functions of inflammatory cells including dendritic cells, monocyte/macrophages, T cells, and B cells along with structural epithelial cells. This review dissects the effects of vitamin D on the inflammatory cells and their therapeutic relevance in pulmonary diseases. Although, the data obtained is very limited and needs further corroboration but presents an exciting area of further research. This is because of its ease of supplementation and development of personalized medicine which could lead us to an effective adjunct and cost-effective method of therapeutic modality for highly fatal pulmonary diseases.

High throughput UHPLC-MS/MS method for the simultaneous quantification of six vitamin D metabolites: application for vitamin D determination in patients after liver or kidney transplantation

Vitamin D metabolites are fat-soluble vitamins that regulate broad spectrum of physiological and pathological processes. Accurate and high-throughput methods for the detection of vitamin D metabolites are essential to elucidate body functions. In this study, a sensitive and high throughput ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) method was proposed for the accurate quantification of six vitamin D metabolites, including vitamin D2, vitamin D3, 25-hydroxyvitamin D2, 25-hydroxyvitamin D3, 1,25-dihydroxyvitamin D2, and 1,25-dihydroxyvitamin D3. Through the optimization of chromatographic and mass spectrometric conditions, only 20 μL serum or plasma could satisfy the quantification of six vitamin D metabolites. The limit of detection (LOD) was determined to be 0.02-0.05 pg mL-1. The validation method was carried out following the International Council for Harmonization (ICH) guidelines. All quantification performances, including linearity, accuracy, precision, extraction recovery and matrix effect, were investigated and were satisfactory for the accurate detection of vitamin D metabolites. A disease of the liver or kidney, the main organs for vitamin D metabolism, could lead to abnormal levels of vitamin D. Here, the established UHPLC-MS/MS method was further used for determination of vitamin D levels in plasma samples of patients after liver or kidney transplantation. Thirty-three liver transplant recipients (LTRs) and 63 kidney transplant recipients (KTRs) were included in this study. Vitamin D deficiency or insufficiency is common in KTRs and LTRs, with a prevalence of more than 99%.

Factors Contributing to Vitamin D Status at Hospital Admission for Pulmonary Exacerbation in Adults With Cystic Fibrosis

BACKGROUND

Individuals with cystic fibrosis (CF) have difficulty maintaining optimal vitamin D status due to pancreatic insufficiency-induced malabsorption, inadequate sunlight exposure, and poor intake of vitamin D containing foods. Vitamin D deficiency may increase the risk of pulmonary exacerbations of CF. The objective of this study was to assess factors impacting vitamin D status in patients with CF recently hospitalized for a pulmonary exacerbation of CF.

METHODS

This was a pre-planned analysis of vitamin D intake in patients enrolled in a multi-center, double-blind, randomized controlled study examining vitamin D therapy for pulmonary exacerbation of CF. Demographic information, responses from a habitual sun exposure questionnaire and food frequency questionnaire, and vitamin D supplement usage were queried and compared to serum 25-hydroxyvitamin D (25(OH)D) concentrations.

RESULTS

A total of 48 subjects were included in this analysis. Subjects were taking approximately 1,200 IU of vitamin D daily. Reported vitamin D intake, age, race, employment, and education were not significantly associated with vitamin D status in this population. However, smoking status, sunlight exposure in the last 3 years, and skin type (in the bivariate model) were all significantly associated with vitamin D status (all p<0.05).

CONCLUSIONS

Sunlight exposure was the most predictive determinant of vitamin D status in patients with CF prior to pulmonary exacerbation. Subjects reported vitamin D intake below the recommended amounts. The role and mode of optimizing vitamin D status prior to a pulmonary exacerbation needs further investigation.

PB. Transcriptomic and Proteostasis Networks of CFTR and the Development of Small Molecule Modulators for the Treatment of Cystic Fibrosis Lung Disease

Cystic fibrosis (CF) is a lethal autosomal recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. The diversity of mutations and the multiple ways by which the protein is affected present challenges for therapeutic development. The observation that the Phe508del-CFTR mutant protein is temperature sensitive provided proof of principle that mutant CFTR could escape proteosomal degradation and retain partial function. Several specific protein interactors and quality control checkpoints encountered by CFTR during its proteostasis have been investigated for therapeutic purposes, but remain incompletely understood. Furthermore, pharmacological manipulation of many CFTR interactors has not been thoroughly investigated for the rescue of Phe508del-CFTR. However, high-throughput screening technologies helped identify several small molecule modulators that rescue CFTR from proteosomal degradation and restore partial function to the protein. Here, we discuss the current state of CFTR transcriptomic and biogenesis research and small molecule therapy development. We also review recent progress in CFTR proteostasis modulators and discuss how such treatments could complement current FDA-approved small molecules.

Targeting Vitamin D Deficiency to Limit Exacerbations in Respiratory Diseases: Utopia or Strategy With Potential?

Patients with respiratory diseases such as cystic fibrosis, chronic obstructive pulmonary disease, or asthma often experience an acute worsening of respiratory symptoms, termed exacerbations. Although the course of exacerbations is disease specific, they are mostly triggered by a respiratory infection. Exacerbations often require hospitalization and are an important cause of mortality. Treatments of exacerbations aim to minimize the negative impact and to prevent subsequent events. Despite many existing therapy options, many patients do not benefit from therapy and suffer from recurrent events. Vitamin D deficiency is a worldwide problem and is extremely prevalent in these patients. Vitamin D, known for its calcemic effects, also has immunomodulatory and anti-infectious actions and can therefore be a possible agent to treat or prevent exacerbations. This review will focus on vitamin D as a potential candidate to treat or prevent exacerbations in CF, COPD, and asthma.

The Immunomodulatory Role of Vitamin D in Respiratory Diseases

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The growing interest in the new role of vitamin D, particularly as an immunomodulatory factor, has spurred basic research and the development of clinical trials to better understand the influence of supplementation on various diseases. Vitamin D is an important nutrient factor in human health due to its role in calcium metabolism regulation, cellular growth, differentiation and its fundamental discovered activity in immune functions. It has influenced different diseases, particularly inflammatory and autoimmune diseases, through immune response regulation, modulating innate and adaptive immunity.

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The aim of this review was to explore the role of vitamin D in the main respiratory diseases in children such as asthma, chronic rhinosinusitis, cystic fibrosis and recurrent respiratory infections.

Vitamin D for the Immune System in Cystic Fibrosis (DISC): a double-blind, multicenter, randomized, placebo-controlled clinical trial

BACKGROUND

Patients with cystic fibrosis (CF) have increased risk of vitamin D deficiency owing to fat malabsorption and other factors. Vitamin D deficiency has been associated with increased risk of pulmonary exacerbations of CF.

OBJECTIVES

The primary objective of this study was to examine the impact of a single high-dose bolus of vitamin D3 followed by maintenance treatment given to adults with CF during an acute pulmonary exacerbation on future recurrence of pulmonary exacerbations.

METHODS

This was a multicenter, double-blind, placebo-controlled, intent-to-treat clinical trial. Subjects with CF were randomly assigned to oral vitamin D3 given as a single dose of 250,000 International Units (IU) or to placebo within 72 h of hospital admission for an acute pulmonary exacerbation, followed by 50,000 IU of vitamin D3 or an identically matched placebo pill taken orally every other week starting at 3 mo after random assignment. The primary outcome was the composite endpoint of the time to next pulmonary exacerbation or death within 1 y. The secondary outcomes included circulating concentrations of the antimicrobial peptide cathelicidin and recovery of lung function as assessed by the percentage of predicted forced expiratory volume in 1 s (FEV1%).

RESULTS

A total of 91 subjects were enrolled in the study. There were no differences between the vitamin D3 and placebo groups in time to next pulmonary exacerbation or death at 1 y. In addition, there were no differences in serial recovery of lung function after pulmonary exacerbation by FEV1% or in serial concentrations of plasma cathelicidin.

CONCLUSIONS

Vitamin D3 initially given at the time of pulmonary exacerbation of CF did not alter the time to the next pulmonary exacerbation, 12-mo mortality, serial lung function, or serial plasma cathelicidin concentrations. This trial was registered at clinicaltrials.gov as NCT01426256.

Bolus Weekly Vitamin D3 Supplementation Impacts Gut and Airway Microbiota in Adults With Cystic Fibrosis: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial

CONTEXT

Disruption of gut microbiota may exacerbate severity of cystic fibrosis (CF). Vitamin D deficiency is a common comorbidity in patients with CF that may influence composition of the gut microbiota.

OBJECTIVES

Compare microbiota of vitamin D-sufficient and -insufficient CF patients and assess impact of a weekly high-dose vitamin D3 bolus regimen on gut and airway microbiome in adults with CF and vitamin D insufficiency (25-hydroxyvitamin D < 30 ng/mL).

DESIGN

Forty-one subjects with CF were classified into two groups: vitamin D insufficient (n = 23) and vitamin D sufficient (n = 18). Subjects with vitamin D insufficiency were randomized to receive 50,000 IU of oral vitamin D3 or placebo weekly for 12 weeks. Sputum and stool samples were obtained pre- and postintervention and 16S ribosomal RNA genes sequenced using Illumina MiSeq technology.

RESULTS

Gut microbiota differed significantly based on vitamin D status with Gammaproteobacteria, which contain numerous, potentially pathogenic species enriched in the vitamin D-insufficient group. Principal coordinates analysis showed differential gut microbiota composition within the vitamin D-insufficient patients following 12 weeks treatment with placebo or vitamin D3 (permutation multivariate analysis of variance = 0.024), with Lactococcus significantly enriched in subjects treated with vitamin D3, whereas Veillonella and Erysipelotrichaceae were significantly enriched in patients treated with placebo.

CONCLUSION

This exploratory study suggests that vitamin D insufficiency is associated with alterations in microbiota composition that may promote inflammation and that supplementation with vitamin D has the potential to impact microbiota composition. Additional studies to determine the impact of vitamin D on microbiota benefit clinical outcomes in CF are warranted.

Role of vitamin D on gut microbiota in cystic fibrosis

This review explores the potential for vitamin D to favorably alter the gut microbiota, given emerging evidence of the role of vitamin D in controlling mucosal inflammation in the gut. It will focus on cystic fibrosis (CF) patients, a population with both vitamin D deficiency due to gut malabsorption and an altered gut microbiota composition. Recent evidence shows that vitamin D acts to maintain the integrity of the gut mucosal barrier by enhancement of intercellular junctions that control mucosal permeability and reduction of pro-inflammatory cytokines such as IL-8. In addition, vitamin D receptor-mediated signaling has been shown to inhibit inflammation-induced apoptosis of intestinal epithelial cells. As a result of these effects on the intestinal mucosa, maintenance of sufficient vitamin D status may be essential for the development of a healthy gut microbiota, particularly in conditions defined by chronic mucosal inflammation such as CF. We hypothesize here that high dose vitamin D may be used to favorably manipulate the aberrant mucosa seen in patients with CF. This may result in improved clinical outcomes in association with a low inflammatory environment that allows beneficial bacteria to outcompete opportunistic pathogens. Current evidence is sparse but encouraging, and additional evidence is needed to establish vitamin D as a therapeutic approach for gut microbiota modification.

Induction of CFTR gene expression by 1,25(OH)2 vitamin D3, 25OH vitamin D3, and vitamin D3 in cultured human airway epithelial cells and in mouse airways

Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which often leads to protein misfolding and no CFTR surface localization. This then leads to chronic airway infections, inflammation, and tissue damage. Although vitamin D has been explored as a therapy to treat CF due to its antimicrobial-inducing and anti-inflammatory properties, the effect of 1,25-dihydroxyvitamin D₃ (1α,25(OH)₂D₃) on CFTR directly has not been studied. We treated cultured healthy and diseased bronchial epithelial cells (BEC) with 10nM 1α,25(OH)₂D₃ for 6 and 24h and found that 1α,25(OH)₂D₃ increases both mRNA and protein CFTR levels using RT-qPCR, flow cytometry and fluorescence immunohistochemistry. Treatment of CF cells with 10nM 1α,25(OH)₂D₃ led to an increase in both total and surface CFTR expression, suggesting 1α,25(OH)₂D₃ could be used to increase properly localized CFTR in airway cells. To determine if BEC could convert the more clinically relevant cholecalciferol to 25OHD₃, cultured non-CF and CF BECs were treated with a range of cholecalciferol concentrations, and 25OHD₃ levels were quantified by ELISA. We found that 25OHD₃ levels increased in a concentration-dependent manner. Treatment of BEC with 10μM cholecalciferol led to increases in both CYP24A1 and CFTR mRNA levels, even when added to the apical surface of cells grown in an air-liquid interface, suggesting that topical administration of vitamin D could be used therapeutically. To demonstrate this in vivo, we intranasally delivered 1μM 1α,25(OH)₂D₃ into mice. After 6h, we observed induction of both Cyp24A1 and CFTR expression in the tracheas of treated mice. The major findings of this study are that vitamin D can be converted to the active form when topically administered to the airway, and this could be used to increase CFTR levels in patients with CF. This could potentially be useful as an adjunctive therapy, together with newly developed CF treatments.

Proinflammatory Cytokines Impair Vitamin D-Induced Host Defense in Cultured Airway Epithelial Cells

Vitamin D is a regulator of host defense against infections and induces expression of the antimicrobial peptide hCAP18/LL-37. Vitamin D deficiency is associated with chronic inflammatory lung diseases and respiratory infections. However, it is incompletely understood if and how (chronic) airway inflammation affects vitamin D metabolism and action. We hypothesized that long-term exposure of primary bronchial epithelial cells to proinflammatory cytokines alters their vitamin D metabolism, antibacterial activity, and expression of hCAP18/LL-37. To investigate this, primary bronchial epithelial cells were differentiated at the air-liquid interface for 14 days in the presence of the proinflammatory cytokines, TNF-α and IL-1β (TNF-α/IL-1β), and subsequently exposed to vitamin D (inactive 25(OH)D₃ and active 1,25(OH)₂D₃). Expression of hCAP18/LL-37, vitamin D receptor, and enzymes involved in vitamin D metabolism (CYP24A1 and CYP27B1) was determined using quantitative PCR, Western blot, and immunofluorescence staining. Furthermore, vitamin D-mediated antibacterial activity was assessed using nontypeable Haemophilus influenzae. We found that TNF-α/IL-1β treatment reduced vitamin D-induced expression of hCAP18/LL-37 and killing of nontypeable H. influenzae. In addition, CYP24A1 (a vitamin D-degrading enzyme) was increased by TNF-α/IL-1β, whereas CYP27B1 (that converts 25(OH)D₃ to its active form) and vitamin D receptor expression remained unaffected. Furthermore, we have demonstrated that the TNF-α/IL-1β-mediated induction of CYP24A1 was, at least in part, mediated by the transcription factor specific protein 1, and the epidermal growth factor receptor-mitogen-activated protein kinase pathway. These findings indicate that TNF-α/IL-1β decreases vitamin D-mediated antibacterial activity and hCAP18/LL-37 expression via induction of CYP24A1 and suggest that chronic inflammation impairs protective responses induced by vitamin D.