Shining a Light on Selenium: a Meta-analysis of Supplementation in Multiple Sclerosis.

Multiple sclerosis (MS) is a chronic immune-mediated demyelinating disease of the central nervous system. Selenium is a trace element with significant antioxidant activity. This study aimed to seek evidence concerning selenium supplementation in MS. A systematic search was performed on PubMed, Web of Science, Scopus, and Embase databases to identify the studies assessing the consumption rate, efficacy, and safety of selenium and selenium-containing supplementations in MS patients. The meta-analysis was performed using the Comprehensive Meta-Analysis and the risk of bias was evaluated using the Joanna Briggs Institute's critical appraisal tools. A total of 9 studies were included, which consisted of six studies regarding the rate of selenium supplement consumption in MS patients, with a total sample size of 2381 patients. Based on the quantitative synthesis, 14.3% (95% CI, 12.8-16.0%; I2, 3.58%) of MS patients had current selenium supplements usage, and 11.3% (95% CI, 7.6-16.6%; I2, 81.40%) of patients had used selenium supplements previously. Although there is no evidence regarding supplementation with selenium alone, three RCT studies reported the safety of selenium-containing supplementation use in MS with improved inflammation and oxidative stress conditions. The findings of this study show that over 10% of patients with MS used selenium supplements, with no clinical significance supporting the benefits. There is a lack of evidence regarding the safety and efficacy of selenium supplements in MS patients. Due to the limited number of included studies and the lack of comprehensive and specific studies regarding selenium supplements in MS, the results must be interpreted with caution, and future clinical trials are required.

Clinical efficacy and safety of melatonin supplementation in multiple sclerosis: a systematic review.

BACKGROUND: Melatonin is a neurohormone secreted predominantly by the pineal gland that is demonstrated to be associated with the pathogenesis of multiple sclerosis (MS). This research desires to evaluate the tolerability and beneficial effects of exogenous melatonin supplementations in patients with MS. METHODS: This study was executed following the PRISMA 2020 statement. Both observational and interventional studies which reported the clinical effectiveness and/or safety of melatonin supplementation in patients with MS were included in this systematic review. Ovid, PubMed, Scopus, Embase, and Web of Science databases were searched and the risk of bias in included studies was assessed using the Joanna Briggs Institute (JBI) critical appraisal tools based on study design. RESULTS: Out of 1304 results of database searches, finally, 14 articles, including 7 randomized controlled trials (RCTs), 6 case-control studies, and one quasi-experimental study, were included based on the full-text review. Included phenotypes of MS were mostly relapsing-remitting MS (RRMS) (in 11 studies); it was secondary progressive MS (SPMS) in only one study, and two other studies had a mixture of the different phenotypes. The course of treatment with melatonin supplementation was between 2 weeks and 12 months. There were no substantial safety issues. Although melatonin was associated with enhanced oxidative stress and inflammation status, concerning the clinical benefits, limited studies suggested improvements in sleep conditions, cognitive outcomes, and fatigue in MS. DISCUSSION: There are insufficient data to support the regular melatonin prescription in MS. Limitations such as the small number of included studies, the diversity of the dosage, route, and duration of melatonin administration, and the diversity of assessment tests lead to unconvincing findings in this study. There is a need for future studies to achieve a comprehensive judgment on this subject.

The effects of magnesium, L-carnitine, and concurrent magnesium-L-carnitine supplementation in migraine prophylaxis.

Given the conflicting results about the positive effects of magnesium and L-carnitine and as there is no report concerning concurrent supplementation of magnesium and L-carnitine on migraine prophylaxis, the effects of magnesium, L-carnitine, and concurrent magnesium-L-carnitine supplementation on migraine indicators were assessed. In this clinical trial, 133 migrainous patients were randomly assigned into three intervention groups: magnesium oxide (500 mg/day), L-carnitine (500 mg/day), and Mg-L-carnitine (500 mg/day magnesium and 500 mg/day L-carnitine), and a control group. After 12 weeks of supplementation, the checklist of migraine indicators including migraine attacks/month, migraine days/month, and headache severity was completed, and serum concentrations of magnesium and L-carnitine were measured by atomic absorption spectrophotometry and enzymatic UV test, respectively. The results showed a significant reduction in all migraine indicators in all studied groups (p < 0.05). The ANOVA results showed a significant reduction in migraine frequency across various supplemented and control groups (p = 0.008). By separating the effects of magnesium supplementation from other confounding factors such as routine treatments using the repeated measures and nested model, it was clarified that magnesium supplementation had a significant effect on all migraine indicators. Oral supplementation with magnesium oxide and L-carnitine and concurrent supplementation of Mg-L-carnitine besides routine treatments could be effective in migraine prophylaxis; however, larger trials are needed to confirm these preliminary findings.