Reduction in circulating vitamin D binding protein in patients with multiple sclerosis

Abstract

Background In this study, we aimed to determine the risk association between vitamin D binding protein (VDBP) polymorphism in patients with multiple sclerosis (MS) in a MS biobank and the difference in VDBP serum levels in MS patients who were recently diagnosed. Method The current case-control study was performed on 296 MS patients and 313 controls. Thereafter, two common missense VDBP polymorphisms, named rs7041and rs4588, were evaluated in all the participants. Serum levels of vitamin D and vitamin D binding protein were assessed in 77 MS patients who were diagnosed since one year ago and in 67 healthy people who were matched in terms of age and sex. Result The frequency distributions of VDBP genotypes and alleles of SNP rs7041 and rs4588 were observed to be similar in both the MS and control groups (p > 0.05). The VDBP haplotypes, as Gc2/Gc2, Gc1/Gc1, and Gc1/Gc2, were found to be similar in the MS and control groups (p > 0.05). In subgroup analysis, circulating VDBP was lower in MS patients (Ln-VDBP (μgr/ml): 3.64 ± 0.91 vs. 5.31 ± 0.77, p = 0.0001) even after adjusting for vitamin D levels, body mass index, and taking vitamin D supplement. There was no significant association between VDBP haplotypes and vitamin D levels in the two groups. Conclusion The present study suggested an association between lower levels of circulating VDBP and multiple sclerosis in newly diagnosed patients. However, the VDBP causative role in the development of MS is still unclear, so it needs more studies.

Alterations in circulating levels of vitamin D binding protein, total and bioavailability of vitamin D in diabetic retinopathy patients

“…The higher levels of PTH as a compensatory mechanism of vitamin D deficiency in diabetic patients can stimulate inflammatory cytokines like tumor necrosis factor (TNF)-α and interleukin (IL)-6 that have important roles in the pathogenesis of DR [ 53 , 54 ]. In line with our study, some studies have mentioned that circulating levels of VDBP are lower in some inflammatory diseases [ 30 , 55 ]. As DR has inflammatory pathogenesis [ 56 ], it suggests that chronic PTH excess in diabetic patients may have indirect effects on circulating levels of VDBP by modulating inflammatory markers.…”

“…The extraction of DNA, genotyping, and phenotyping of VDBP have been described in our previous study [ 30 ].…”

Treatment With 25-Hydroxyvitamin D3 (Calcifediol) Is Associated With a Reduction in the Blood Neutrophil-to-Lymphocyte Ratio Marker of Disease Severity in Hospitalized Patients With COVID-19: A Pilot Multicenter, Randomized, Placebo-Controlled, Double-Blinded Clinical Trial

“…Total serum 25(OH)D was measured by HPLC. The method of HPLC was described in our recent study ( 20 ).…”

Free vitamin D3 index and vitamin D‐binding protein in multiple sclerosis: A presymptomatic case–control study

“…This suggests that 25(OH)D 3 status should be assessed with regard to DBP concentration to determine the free fraction [11]. Only three studies have previously analyzed the free portion of 25(OH)D 3 as a risk marker for MS, and their results are diverging [12][13][14]. These studies included relatively few cases (n = 76, 91, and 77, respectively) and used samples drawn after diagnosis of MS or clinically isolated syndrome, which confers the risk of reverse causality.…”

“…DBP may thus influence MS pathophysiology both by itself and in conjunction with the vitamin D metabolites [17]. The role of DBP in MS etiopathogenesis has been assessed in several studies, also with inconclusive results [12][13][14][18][19][20][21][22][23]. Again, these studies were small (n = 18-183) and performed on samples collected after disease onset.…”