The effect of crocin-selenium nanoparticles on the cognition and oxidative stress markers of multiple sclerosis patients: a randomized triple-blinded placebo-controlled clinical trial.

The prevalence of cognitive impairment in multiple sclerosis (MS) patients is estimated to be approximately 40-60%. There is an increasing body of evidence regarding the impact of both selenium and crocin as antioxidant agents on cognitive function. In the present study, for the first time, we investigated the effect of crocin-selenium nanoparticles (Cor@SeNs) on cognitive function and oxidative stress markers in MS patients. A triple-blind randomized clinical trial was conducted among 60 MS patients. The participants were randomly divided in a 1:1 ratio to either the Cor@SeNs or placebo group, employing block randomization. During the course of 12 weeks, the participants received Cor@SeNs capsules, containing 5.74 mg crocin and 55 mcg Selenium, or placebo capsules. Cognition assessed using the Persian version of the Brief International Cognitive Assessment for MS (BICAMS) battery. Serum levels of total antioxidant capacity (TAC), glutathione reductase (GR) activity and malondialdehyde (MDA) determined by colorimetric kits. Data analysis was performed in SPSS, version 26. P < 0.05 was considered as the significant range. The mean ± SD of TAC change was 0.03 ± 0.07 mM vs. - 0.03 ± 0.09 mM in intervention and placebo groups, respectively (Time × group effect P: 0.01; effect size: 0.10). The time effect of intervention on the California Verbal Learning Test second edition (CVLT-II) (P < 0.01; effect size: 0.29), CVLT-II-delay (P < 0.01; effect size: 0.29), and the Symbol Digit Modalities Test (SDMT) (P < 0.01; effect size: 0.18) was increasing and significant. In addition, the time effect of intervention on GR activity was significant and decreasing in both groups (P < 0.01; effect size: 0.20). Our results suggested a significant effect of the Cor@SeNs intervention in improving TAC. We also observed a significant improvement in cognitive function in both groups during our study. However, although not statistically significant, a higher amount of change in cognitive function and serum antioxidant markers was noted in the Cor@SeNs group compared to the placebo group. This is the first study on this nano product with low dose of selenium and crocin. More investigations with longer duration and varied doses are suggested.