Vitamin D related genetic polymorphisms affect serological response to high-dose vitamin D supplementation in multiple sclerosis

Vitamin D Supplementation in Functional Recovery of Subjects with Severe Acquired Brain Injury: A Pilot Controlled Randomized Study

Low vitamin D (VD) has been associated with poor clinical course in several neurological diseases. Supplementation has been suggested to improve outcomes. Severe acquired brain injury (sABI) subjects have low VD levels and disabling conditions requiring rehabilitation. The aim of the present study was to evaluate if VD supplementation produced a better clinical course and a better functional outcome in sABI during rehabilitation. A randomized single-blind study was performed. sABI subjects were randomized to the VD supplementation group (VDsG) (initial dose of 50.000 UI and 1.000 daily) and usual care control group (CG). Disability Rating Scale (DRS), Glasgow Outcome Scale (GOS), and Level of Cognitive Functioning (LCF) were used in assessing disability. A total of 73 subjects (42 M and 31 F; mean age 53.2 ± 15.7) were randomized: 36 (21 M and 15 F; mean age 57.52 ± 14.88) to VDsG and 37 (20 M and 17 F; mean age 48.28 ± 17.47) to CG. Both groups significantly improved after rehabilitation, and no between-group difference was observed. The mean score values for DRS, GOS, and LCF in VDsG were 18.83 ± 4.27 and 9.42 ± 5.83; 2.89 ± 0.32 and 3.78 ± 0.80; and 4.81 ± 1.70 and 7.53 ± 1.28, at admission and discharge, respectively. Likewise, mean values for DRS, GOS, and LCF in CG were 18.57 ± 4.80 and 9.84 ± 6.34; 2.84 ± 0.37 and 3.81 ± 0.94; and 4.97 ± 2.01 and 7.41 ± 1.32, respectively. VD supplementation did not improve functional outcomes in sABI during rehabilitation treatment.

Vitamin D-Binding Protein and the Role of its Gene Polymorphisms in the Mortality of Sepsis Patients

OBJECTIVE

This study aimed to determine the role of vitamin D-binding protein (VDBP) gene polymorphisms (especially at locus rs7041), vitamin D-binding protein levels, and vitamin D levels in mortality in sepsis patients.

PATIENTS AND METHODS

We performed the analytic observational study with a case-control approach. A total of 80 patients were included in this study, 40 patients were grouped as the case group and 40 patients were grouped as the control group. The patients were diagnosed with sepsis and treated in the Intensive Care Unit (ICU), M. Djamil Hospital, Indonesia. The VDBP rs7041 gene polymorphism was analyzed using the polymerase chain reaction procedure. VDBP and vitamin D levels were examined using the enzyme-linked immunosorbent assay (ELISA) method.

RESULTS

The case group showed lower mean vitamin D and VDBP levels than the control group (P<0.05). There were more variations in the rs7041 gene VDBP (mutant) locus in the case group than in the control group, and this difference was considered statistically significant, P<0.05. The results of this study indicate that the occurrence of polymorphism or variations at locus rs7401 (mutant) causes a decrease in VDBP and vitamin D levels. A decrease in vitamin D levels correlates with the incidence of mortality in sepsis patients.

CONCLUSION

Polymorphism gene VDBP at locus rs7041 causes a decrease in the production of VDBP, a vitamin D carrier protein.

Association of Vitamin D Polygenic Risk Scores and Disease Outcome in People With Multiple Sclerosis

Background and Objectives

Observational studies suggest low levels of 25-hydroxyvitamin D (25[OH]D) may be associated with increased disease activity in people with multiple sclerosis (PwMS). Large-scale genome-wide association studies (GWAS) suggest 25(OH)D levels are partly genetically determined. The resultant polygenic scores (PGSs) could serve as a proxy for 25(OH)D levels, minimizing potential confounding and reverse causation in analyses with outcomes. Herein, we assess the association of genetically determined 25(OH)D and disease outcomes in MS.

Methods

We generated 25(OH)D PGS for 1,924 PwMS with available genotyping data pooled from 3 studies: the CombiRx trial (n = 575), Johns Hopkins MS Center (n = 1,152), and Immune-Mediated Inflammatory Diseases study (n = 197). 25(OH)D-PGS were derived using summary statistics (p < 5 × 10−8) from a large GWAS including 485,762 individuals with circulating 25(OH)D levels measured. We included clinical and imaging outcomes: Expanded disability status scale (EDSS), timed 25-foot walk (T25FW), nine-hole peg test (9HPT), radiologic activity, and optical coherence tomography-derived ganglion cell inner plexiform layer (GCIPL) thickness. A subset (n = 935) had measured circulating 25(OH)D levels. We fitted multivariable models based on the outcome of interest and pooled results across studies using random effects meta-analysis. Sensitivity analyses included a modifiedpvalue threshold for inclusion in the PGS (5 × 10−5) and applying Mendelian randomization (MR) rather than using PGS.

Results

Initial analyses demonstrated a positive association between generated 25(OH)D-PGS and circulating 25(OH)D levels (per 1SD increase in 25[OH]D PGS: 3.08%, 95% CI: 1.77%, 4.42%;p= 4.33e-06; R2= 2.24%). In analyses with outcomes, we did not observe an association between 25(OH)D-PGS and relapse rate (per 1SD increase in 25[OH]D-PGS: 0.98; 95% CI: 0.87–1.10), EDSS worsening (per 1SD: 1.05; 95% CI: 0.87–1.28), change in T25FW (per 1SD: 0.07%; 95% CI: −0.34 to 0.49), or change in 9HPT (per 1SD: 0.09%; 95% CI: −0.15 to 0.33). 25(OH)D-PGS was not associated with new lesion accrual, lesion volume or other imaging-based outcomes (whole brain, gray, white matter volume loss or GCIPL thinning). The results were similarly null in analyses using otherpvalue thresholds or those applying MR.

Discussion

Genetically determined lower 25(OH)D levels were not associated with worse disease outcomes in PwMS and raises questions about the plausibility of a treatment effect of vitamin D in established MS.

Risk Factors from Pregnancy to Adulthood in Multiple Sclerosis Outcome

Multiple sclerosis (MS) is an autoimmune disease characterized by a robust inflammatory response against myelin sheath antigens, which causes astrocyte and microglial activation and demyelination of the central nervous system (CNS). Multiple genetic predispositions and environmental factors are known to influence the immune response in autoimmune diseases, such as MS, and in the experimental autoimmune encephalomyelitis (EAE) model. Although the predisposition to suffer from MS seems to be a multifactorial process, a highly sensitive period is pregnancy due to factors that alter the development and differentiation of the CNS and the immune system, which increases the offspring’s susceptibility to develop MS. In this regard, there is evidence that thyroid hormone deficiency during gestation, such as hypothyroidism or hypothyroxinemia, may increase susceptibility to autoimmune diseases such as MS. In this review, we discuss the relevance of the gestational period for the development of MS in adulthood.

Improving Glucocorticoid Sensitivity of Brain-Homing CD4+ T Helper Cells by Steroid Hormone Crosstalk

In early multiple sclerosis (MS), an IFN-γ^highGM-CSF^highIL-17^low CD4⁺ T-cell subset termed T helper 17.1 (Th17.1) reveals enhanced capacity to infiltrate the central nervous system. Th17.1 cells express high levels of multidrug resistance protein 1 (MDR1), which contributes to their poor glucocorticoid responsiveness. In this study, we explored whether glucocorticoid sensitivity of Th17.1 cells can generically be improved through synergy between steroid hormones, including calcitriol (1,25(OH)₂D₃), estradiol (E2) and progesterone (P4). We showed that human blood Th17.1 cells were less sensitive to 1,25(OH)₂D₃ than Th17 cells, as reflected by lower vitamin D receptor (VDR) levels and reduced modulation of MDR1, IFN-γ and GM-CSF expression after 1,25(OH)₂D₃ exposure. Upon T-cell activation, VDR levels were increased, but still lower in Th17.1 versus Th17 cells, which was accompanied by a 1,25(OH)₂D₃-mediated decline in MDR1 surface expression as well as secretion of IFN-γ and GM-CSF. In activated Th17.1 cells, 1,25(OH)₂D₃ amplified the suppressive effects of methylprednisolone (MP) on proliferation, MDR1 surface levels, secretion of IFN-γ and granzyme B, as well as expression of brain-homing markers CCR6 and VLA-4. The addition of P4 to 1,25(OH)₂D₃ further enhanced MP-mediated reduction in proliferation, CD25, CCR6 and CXCR3. Overall, this study indicates that glucocorticoid sensitivity of Th17.1 cells can be enhanced by treatment with 1,25(OH)₂D₃ and further improved with P4. Our observations implicate steroid hormone crosstalk as a therapeutic avenue in Th17.1-associated inflammatory diseases including MS.

Environmental risk factors in multiple sclerosis: bridging Mendelian randomization and observational studies

Multiple sclerosis (MS) is a complex disease with both genetic variants and environmental factors involved in disease susceptibility. The main environmental risk factors associated with MS in observational studies include obesity, vitamin D deficiency, Epstein-Barr virus infection and smoking. As modifying these environmental and lifestyle factors may enable prevention, it is important to pinpoint causal links between these factors and MS. Leveraging genetics through the Mendelian randomization (MR) paradigm is an elegant way to inform prevention strategies in MS. In this review, we summarize MR studies regarding the impact of environmental factors on MS susceptibility, thereby paying attention to quality criteria which will aid readers in interpreting any MR studies. We draw parallels and differences with observational studies and randomized controlled trials and look forward to the challenges that such work presents going forward.