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

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.

ESPEN-ESPGHAN-ECFS guideline on nutrition care for cystic fibrosis

BACKGROUND

Nutritional status is paramount in Cystic Fibrosis (CF) and is directly correlated with morbidity and mortality. The first ESPEN-ESPGHAN-ECFS guidelines on nutrition care for infants, children, and adults with CF were published in 2016. An update to these guidelines is presented.

METHODS

The study was developed by an international multidisciplinary working group in accordance with officially accepted standards. Literature since 2016 was reviewed, PICO questions were discussed and the GRADE system was utilized. Statements were discussed and submitted for on-line voting by the Working Group and by all ESPEN members.

RESULTS

The Working Group updated the nutritional guidelines including assessment and management at all ages. Supplementation of vitamins and pancreatic enzymes remains largely the same. There are expanded chapters on pregnancy, CF-related liver disease, and CF-related diabetes, bone disease, nutritional and mineral supplements, and probiotics. There are new chapters on nutrition with highly effective modulator therapies and nutrition after organ transplantation.

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.

Calcipotriol Attenuates Form Deprivation Myopia Through a Signaling Pathway Parallel to TGF-β2-Induced Increases in Collagen Expression

Purpose

To determine the role of calcipotriol, a vitamin D3 analogue, in myopia development and altering the expression of scleral α1 chain of type I collagen (Col1α1) in mice. We also aimed to identify if the signaling pathway mediating the above changes is different from the one involved in transforming growth factor β2 (TGF-β2)-mediated increases of COL1A1 in cultured human scleral fibroblasts (HSFs).

Methods

C57BL/6J mice were either intraperitoneally injected with calcipotriol and subjected to form deprivation (FD) or exposed to normal refractive development for 4 weeks. Scleral vitamin D receptor (Vdr) expression was knocked down using a Sub-Tenon's capsule injection of an adeno-associated virus-packaged short hairpin RNA (AAV8-shRNA). Refraction and biometric measurements evaluated myopia development. A combination of knockdown and induction strategies determined the relative contributions of the vitamin D3 and the TGF-β2 signaling pathways in modulating COL1A1 expression in HSFs.

Results

Calcipotriol injections suppressed FD-induced myopia (FDM), but it had no significant effect on normal refractive development. AAV8-shRNA injection reduced Vdr mRNA expression by 42% and shifted the refraction toward myopia (-3.15 ± 0.99D, means ± SEM) in normal eyes. In HSFs, VDR knockdown reduced calcipotriol-induced rises in COL1A1 expression, but it did not alter TGF-β2-induced increases in COL1A1 expression. Additionally, TGF-β2 augmented calcipotriol-induced rises in COL1A1 expression. TGF-β receptor (TGFBRI/II) knockdown blunted TGF-β2-induced increases in COL1A1 expression, whereas calcipotriol-induced increases in VDR and COL1A1 expression levels were unaltered.

Conclusions

Scleral vitamin D3 inhibits myopia development in mice, potentially by activating a VDR-dependent signaling pathway and increasing scleral COL1A1 expression levels.