The effects of vitamin D supplementation on interictal serum levels of calcitonin gene-related peptide (CGRP) in episodic migraine patients: post hoc analysis of a randomized double-blind placebo-controlled trial.

BACKGROUND: Emerging evidence showed promising effects of vitamin D on headaches characteristics. Thus, it seems there is still a need for more researches to clarify the mechanisms by which this vitamin exerts anti-migraine effects. METHODS: The present study was conducted as a 16-week randomized double-blind placebo-controlled trial on 80 episodic migraine patients allocated in 2 parallel groups each consisted of 40 patients who received vitamin D 2000 IU/d or placebo. At baseline and after the intervention completion, headache diaries and migraine disability assessment questionnaire (MIDAS) were used to assess migraine related variables in patients. Also, interictal serum concentration of calcitonin gene-related peptide (CGRP) (as the dominant mediator of migraine pain pathogenesis) was evaluated using ELISA method. RESULTS: The mean (SD) of age in the vitamin D and placebo groups was 37 (8) and 38 (12) years, respectively. ANCOVA test adjusted for baseline values, and confounders showed vitamin D supplementation resulted in a significant improvement in MIDAS score after 12 weeks in the intervention group (21.49 (16.22-26.77)) compared to placebo (31.16 (25.51-36.82) P value: 0.016). Moreover, after controlling for baseline levels, and other variables using ANCOVA, CGRP level was appeared to be significantly lower following vitamin D supplementation (153.26 (133.03-173.49) ng/L) than the patients in the placebo arm (188.35 (167.15-209.54) ng/L) (P value = 0.022). CONCLUSION: According to the current findings, vitamin D supplementation in episodic migraineurs, particularly in those with migraine with aura, may potentially improve migraine headache characteristics and disability probably through attenuating CGRP levels. Therefore, these results could provide a new insight into anti-nociceptive effects of vitamin D; however, more studies are required to confirm our findings. TRIAL REGISTRATION: The trial is registered in the Iranian registry of clinical trials (IRCT) at 11 July 2018, with IRCT code: IRCT20151128025267N6.

Vitamin D3 might improve headache characteristics and protect against inflammation in migraine: a randomized clinical trial.

INTRODUCTION: Due to anti-inflammatory effects of vitamin D3, we aimed to explore the effects of supplementation with this vitamin on headache characteristics and serum levels of pro/anti-inflammatory markers in migraineurs. METHODS AND MATERIALS: This placebo-controlled, double-blind study included 80 episodic migraineurs who randomly assigned into two equal groups to receive either daily dose of vitamin D3 2000 IU (50 µg) or placebo for 12 weeks. At baseline and after the trial, headache characteristics were determined using diaries and serum levels of interleukin (IL)-10, IL-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (Cox-2) were assessed via ELISA method. RESULTS: At the end of trial, analysis of covariance (ANCOVA) adjusted for baseline values, and confounders revealed that vitamin D3 supplemented group experienced significantly lower headache days per month (4.71), reduced attacks duration (12.99 h/attack), less severe headaches (5.47, visual analog scale), and lower analgesics use/month (2.85) than placebo group (6.43, 18.32, 6.38 and 4.87, respectively) (P values < 0.05). Using ANCOVA adjusted for baseline levels and confounding variables, it was found that serum levels of IL-10 and Cox-2 did not significantly differ between groups after the experiment; whereas, iNOS serum level was significantly reduced in the intervention group (106.06 U/L) comparing to the controls (156.18 U/L P : 0.001). Also, the patients receiving vitamin D3 yielded a marginally significant lower IL-6 serum concentration (76.43 ng/L) compared to placebo (93.10 ng/L) (P value:0.055). CONCLUSION: Based on the results of this study, we found that 2000 IU (50 µg)/day vitamin D3 supplementation for 12 weeks could improve headache characteristics and might reduce neuro-inflammation in episodic migraine.

Retinyl Palmitate Supplementation Modulates T-bet and Interferon Gamma Gene Expression in Multiple Sclerosis Patients.

Vitamin A derivatives such as retinoic acid may improve the impaired balance of CD4+ T cells in autoimmune and inflammatory diseases. This study is a double-blind randomized trial to evaluate the effect of vitamin A (as form of retinyl palmitate) supplementation on multiple sclerosis (MS) patients. Thirty-nine patients were enrolled and randomly assigned to two groups. Both groups were followed for 6 months. The experimental group received 25,000 IU of retinyl palmitate daily, while the control group received a placebo. Before and after the study, the expression of interferon gamma (IFN-γ) and T-bet genes was evaluated in peripheral blood mononuclear cells of patients by RT-PCR. The results showed that after 6 months of supplementation, expression of IFN-γ and T-bet was significantly decreased. These data suggest that retinyl palmitate supplementation can modulate the impaired balance of Th1 and Th2 cells and vitamin A products that may be involved in the therapeutic mechanism of vitamin A in MS patients. This study provides information regarding the decreased gene expression of IFN-γ and T-bet in MS by retinyl palmitate supplementation.

ω-3 fatty acid differentially modulated serum levels of IGF1 and IGFBP3 in men with CVD: a randomized, double-blind placebo-controlled study.

OBJECTIVE: Studies have reported elevated serum insulin-like growth factor (IGF)-1 levels followed by ω-3 supplementation in various groups. Considering decreased level of IGF1 in patients with cardiovascular disease (CVD) and protective effects of IGF1 against CVD progression and myocardial infarctions mortality, this study was performed with the aim of determining effects of ω-3 supplementation on serum levels and gene expression of IGF1 and IGF binding protein-3 (IGFBP3) in men with CVD. METHODS: Sixty-two middle-aged (55.9 ± 6.5 y) non-obese men with CVD followed the study protocol in two groups of ω-3 (n = 31) or placebo (n = 31) supplementation. Participants took ω-3 supplement or placebo (edible paraffin) for 8 wk and were asked not to change their diet or physical activity plan. Anthropometric and lipid profile characteristics, serum IGF1, serum IGFBP3 and also IGF1 and IGFBP3 gene expression in peripheral blood mononuclear cells (PBMCs) were measured in all participants before and after the intervention. Statistical analyses were performed using SPSS software. RESULTS: There were no significant differences between the two study groups in age and body mass index at baseline. The groups also had no difference in baseline serum low-density lipoprotein, high-density lipoprotein, very low-density lipoprotein, triacylglycerols, and IGF1. Compared with placebo, ω-3 supplementation increased serum IGF1 levels (P = 0.01), and decreased serum level of IGFBP3 (P = 0.02). There was a trending toward an increase in IGF1 expression and nonsignificant decrease in IGFBP3 expression. CONCLUSIONS: ω-3 supplementation in patients with CVD increases serum IGF1 levels and decreases serum IGFBP3. Further research is warranted to investigate the underlying mechanisms.